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4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<title>Chapter�4.�Advanced DNS Features</title>
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4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="titlepage"><div><div><h1 class="title">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="Bv9ARM.ch04"></a>Chapter�4.�Advanced DNS Features</h1></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="toc">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p><b>Table of Contents</b></p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dl class="toc">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#notify">Notify</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#dynamic_update">Dynamic Update</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dd><dl><dt><span class="section"><a href="Bv9ARM.ch04.html#journal">The journal file</a></span></dt></dl></dd>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#incremental_zone_transfers">Incremental Zone Transfers (IXFR)</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#split_dns">Split DNS</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dd><dl><dt><span class="section"><a href="Bv9ARM.ch04.html#split_dns_sample">Example split DNS setup</a></span></dt></dl></dd>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#tsig">TSIG</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dd><dl>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.6.5">Generating a Shared Key</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.6.6">Loading A New Key</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.6.7">Instructing the Server to Use a Key</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.6.8">TSIG-Based Access Control</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.6.9">Errors</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</dl></dd>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#tkey">TKEY</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#sig0">SIG(0)</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#DNSSEC">DNSSEC</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dd><dl>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#dnssec_keys">Generating Keys</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#dnssec_signing">Signing the Zone</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#dnssec_config">Configuring Servers</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</dl></dd>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#dnssec.dynamic.zones">DNSSEC, Dynamic Zones, and Automatic Signing</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dd><dl>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.10.3">Converting from insecure to secure</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.10.8">Dynamic DNS update method</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.10.16">Fully automatic zone signing</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.10.25">Private-type records</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.10.32">DNSKEY rollovers</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.10.34">Dynamic DNS update method</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.10.39">Automatic key rollovers</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.10.41">NSEC3PARAM rollovers via UPDATE</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.10.43">Converting from NSEC to NSEC3</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.10.45">Converting from NSEC3 to NSEC</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.10.47">Converting from secure to insecure</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.10.51">Periodic re-signing</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.10.53">NSEC3 and OPTOUT</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</dl></dd>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#rfc5011.support">Dynamic Trust Anchor Management</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dd><dl>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.11.3">Validating Resolver</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.11.4">Authoritative Server</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</dl></dd>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#pkcs11">PKCS#11 (Cryptoki) support</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dd><dl>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.12.6">Prerequisites</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.12.7">Native PKCS#11</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.12.8">OpenSSL-based PKCS#11</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.12.9">PKCS#11 Tools</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.12.10">Using the HSM</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.12.11">Specifying the engine on the command line</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.12.12">Running named with automatic zone re-signing</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</dl></dd>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#dlz-info">DLZ (Dynamically Loadable Zones)</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dd><dl>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.13.6">Configuring DLZ</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.13.7">Sample DLZ Driver</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</dl></dd>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#dyndb-info">DynDB (Dynamic Database)</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dd><dl>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.14.5">Configuring DynDB</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.14.6">Sample DynDB Module</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</dl></dd>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#catz-info">Catalog Zones</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dd><dl>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.15.4">Principle of Operation</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.15.5">Configuring Catalog Zones</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.15.6">Catalog Zone format</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</dl></dd>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#ipv6">IPv6 Support in <acronym class="acronym">BIND</acronym> 9</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dd><dl>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.16.6">Address Lookups Using AAAA Records</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<dt><span class="section"><a href="Bv9ARM.ch04.html#id-1.5.16.7">Address to Name Lookups Using Nibble Format</a></span></dt>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</dl></dd>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</dl>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="titlepage"><div><div><h2 class="title" style="clear: both">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="notify"></a>Notify</h2></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <acronym class="acronym">DNS</acronym> NOTIFY is a mechanism that allows master
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync servers to notify their slave servers of changes to a zone's data. In
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync response to a <span class="command"><strong>NOTIFY</strong></span> from a master server, the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync slave will check to see that its version of the zone is the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync current version and, if not, initiate a zone transfer.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync For more information about <acronym class="acronym">DNS</acronym>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>NOTIFY</strong></span>, see the description of the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>notify</strong></span> option in <a class="xref" href="Bv9ARM.ch06.html#boolean_options" title="Boolean Options">the section called &#8220;Boolean Options&#8221;</a> and
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the description of the zone option <span class="command"><strong>also-notify</strong></span> in
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <a class="xref" href="Bv9ARM.ch06.html#zone_transfers" title="Zone Transfers">the section called &#8220;Zone Transfers&#8221;</a>. The <span class="command"><strong>NOTIFY</strong></span>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync protocol is specified in RFC 1996.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<h3 class="title">Note</h3>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync As a slave zone can also be a master to other slaves, <span class="command"><strong>named</strong></span>,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync by default, sends <span class="command"><strong>NOTIFY</strong></span> messages for every zone
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync it loads. Specifying <span class="command"><strong>notify master-only;</strong></span> will
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync cause <span class="command"><strong>named</strong></span> to only send <span class="command"><strong>NOTIFY</strong></span> for master
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync zones that it loads.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="titlepage"><div><div><h2 class="title" style="clear: both">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="dynamic_update"></a>Dynamic Update</h2></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Dynamic Update is a method for adding, replacing or deleting
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync records in a master server by sending it a special form of DNS
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync messages. The format and meaning of these messages is specified
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync in RFC 2136.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Dynamic update is enabled by including an
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>allow-update</strong></span> or an <span class="command"><strong>update-policy</strong></span>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync clause in the <span class="command"><strong>zone</strong></span> statement.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync If the zone's <span class="command"><strong>update-policy</strong></span> is set to
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <strong class="userinput"><code>local</code></strong>, updates to the zone
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync will be permitted for the key <code class="varname">local-ddns</code>,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync which will be generated by <span class="command"><strong>named</strong></span> at startup.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync See <a class="xref" href="Bv9ARM.ch06.html#dynamic_update_policies" title="Dynamic Update Policies">the section called &#8220;Dynamic Update Policies&#8221;</a> for more details.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Dynamic updates using Kerberos signed requests can be made
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync using the TKEY/GSS protocol by setting either the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>tkey-gssapi-keytab</strong></span> option, or alternatively
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync by setting both the <span class="command"><strong>tkey-gssapi-credential</strong></span>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync and <span class="command"><strong>tkey-domain</strong></span> options. Once enabled,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Kerberos signed requests will be matched against the update
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync policies for the zone, using the Kerberos principal as the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync signer for the request.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Updating of secure zones (zones using DNSSEC) follows RFC
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync 3007: RRSIG, NSEC and NSEC3 records affected by updates are
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync automatically regenerated by the server using an online
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync zone key. Update authorization is based on transaction
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync signatures and an explicit server policy.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="titlepage"><div><div><h3 class="title">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="journal"></a>The journal file</h3></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync All changes made to a zone using dynamic update are stored
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync in the zone's journal file. This file is automatically created
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync by the server when the first dynamic update takes place.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync The name of the journal file is formed by appending the extension
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <code class="filename">.jnl</code> to the name of the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync corresponding zone
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync file unless specifically overridden. The journal file is in a
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync binary format and should not be edited manually.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync The server will also occasionally write ("dump")
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the complete contents of the updated zone to its zone file.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync This is not done immediately after
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync each dynamic update, because that would be too slow when a large
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync zone is updated frequently. Instead, the dump is delayed by
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync up to 15 minutes, allowing additional updates to take place.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync During the dump process, transient files will be created
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync with the extensions <code class="filename">.jnw</code> and
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <code class="filename">.jbk</code>; under ordinary circumstances, these
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync will be removed when the dump is complete, and can be safely
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync ignored.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync When a server is restarted after a shutdown or crash, it will replay
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the journal file to incorporate into the zone any updates that
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync took
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync place after the last zone dump.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Changes that result from incoming incremental zone transfers are
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync also
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync journalled in a similar way.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync The zone files of dynamic zones cannot normally be edited by
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync hand because they are not guaranteed to contain the most recent
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync dynamic changes &#8212; those are only in the journal file.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync The only way to ensure that the zone file of a dynamic zone
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync is up to date is to run <span class="command"><strong>rndc stop</strong></span>.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync If you have to make changes to a dynamic zone
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync manually, the following procedure will work:
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Disable dynamic updates to the zone using
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>rndc freeze <em class="replaceable"><code>zone</code></em></strong></span>.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync This will update the zone's master file with the changes
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync stored in its <code class="filename">.jnl</code> file.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Edit the zone file. Run
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>rndc thaw <em class="replaceable"><code>zone</code></em></strong></span>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync to reload the changed zone and re-enable dynamic updates.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>rndc sync <em class="replaceable"><code>zone</code></em></strong></span>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync will update the zone file with changes from the journal file
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync without stopping dynamic updates; this may be useful for viewing
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the current zone state. To remove the <code class="filename">.jnl</code>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync file after updating the zone file, use
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>rndc sync -clean</strong></span>.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="titlepage"><div><div><h2 class="title" style="clear: both">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="incremental_zone_transfers"></a>Incremental Zone Transfers (IXFR)</h2></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync The incremental zone transfer (IXFR) protocol is a way for
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync slave servers to transfer only changed data, instead of having to
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync transfer the entire zone. The IXFR protocol is specified in RFC
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync 1995. See <a class="xref" href="Bv9ARM.ch11.html#proposed_standards" title="Proposed Standards">Proposed Standards</a>.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync When acting as a master, <acronym class="acronym">BIND</acronym> 9
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync supports IXFR for those zones
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync where the necessary change history information is available. These
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync include master zones maintained by dynamic update and slave zones
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync whose data was obtained by IXFR. For manually maintained master
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync zones, and for slave zones obtained by performing a full zone
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync transfer (AXFR), IXFR is supported only if the option
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>ixfr-from-differences</strong></span> is set
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync to <strong class="userinput"><code>yes</code></strong>.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync When acting as a slave, <acronym class="acronym">BIND</acronym> 9 will
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync attempt to use IXFR unless
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync it is explicitly disabled. For more information about disabling
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync IXFR, see the description of the <span class="command"><strong>request-ixfr</strong></span> clause
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync of the <span class="command"><strong>server</strong></span> statement.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="titlepage"><div><div><h2 class="title" style="clear: both">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="split_dns"></a>Split DNS</h2></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Setting up different views, or visibility, of the DNS space to
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync internal and external resolvers is usually referred to as a
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="emphasis"><em>Split DNS</em></span> setup. There are several
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync reasons an organization would want to set up its DNS this way.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync One common reason for setting up a DNS system this way is
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync to hide "internal" DNS information from "external" clients on the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Internet. There is some debate as to whether or not this is actually
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync useful.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Internal DNS information leaks out in many ways (via email headers,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync for example) and most savvy "attackers" can find the information
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync they need using other means.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync However, since listing addresses of internal servers that
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync external clients cannot possibly reach can result in
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync connection delays and other annoyances, an organization may
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync choose to use a Split DNS to present a consistent view of itself
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync to the outside world.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Another common reason for setting up a Split DNS system is
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync to allow internal networks that are behind filters or in RFC 1918
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync space (reserved IP space, as documented in RFC 1918) to resolve DNS
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync on the Internet. Split DNS can also be used to allow mail from outside
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync back in to the internal network.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="titlepage"><div><div><h3 class="title">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="split_dns_sample"></a>Example split DNS setup</h3></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Let's say a company named <span class="emphasis"><em>Example, Inc.</em></span>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync (<code class="literal">example.com</code>)
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync has several corporate sites that have an internal network with
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync reserved
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Internet Protocol (IP) space and an external demilitarized zone (DMZ),
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync or "outside" section of a network, that is available to the public.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="emphasis"><em>Example, Inc.</em></span> wants its internal clients
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync to be able to resolve external hostnames and to exchange mail with
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync people on the outside. The company also wants its internal resolvers
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync to have access to certain internal-only zones that are not available
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync at all outside of the internal network.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync In order to accomplish this, the company will set up two sets
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync of name servers. One set will be on the inside network (in the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync reserved
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync IP space) and the other set will be on bastion hosts, which are
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync "proxy"
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync hosts that can talk to both sides of its network, in the DMZ.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync The internal servers will be configured to forward all queries,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync except queries for <code class="filename">site1.internal</code>, <code class="filename">site2.internal</code>, <code class="filename">site1.example.com</code>,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync and <code class="filename">site2.example.com</code>, to the servers
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync in the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync DMZ. These internal servers will have complete sets of information
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync for <code class="filename">site1.example.com</code>, <code class="filename">site2.example.com</code>, <code class="filename">site1.internal</code>,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync and <code class="filename">site2.internal</code>.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync To protect the <code class="filename">site1.internal</code> and <code class="filename">site2.internal</code> domains,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the internal name servers must be configured to disallow all queries
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync to these domains from any external hosts, including the bastion
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync hosts.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync The external servers, which are on the bastion hosts, will
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync be configured to serve the "public" version of the <code class="filename">site1</code> and <code class="filename">site2.example.com</code> zones.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync This could include things such as the host records for public servers
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync (<code class="filename">www.example.com</code> and <code class="filename">ftp.example.com</code>),
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync and mail exchange (MX) records (<code class="filename">a.mx.example.com</code> and <code class="filename">b.mx.example.com</code>).
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync In addition, the public <code class="filename">site1</code> and <code class="filename">site2.example.com</code> zones
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync should have special MX records that contain wildcard (`*') records
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync pointing to the bastion hosts. This is needed because external mail
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync servers do not have any other way of looking up how to deliver mail
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync to those internal hosts. With the wildcard records, the mail will
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync be delivered to the bastion host, which can then forward it on to
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync internal hosts.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Here's an example of a wildcard MX record:
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<pre class="programlisting">* IN MX 10 external1.example.com.</pre>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Now that they accept mail on behalf of anything in the internal
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync network, the bastion hosts will need to know how to deliver mail
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync to internal hosts. In order for this to work properly, the resolvers
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync on
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the bastion hosts will need to be configured to point to the internal
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync name servers for DNS resolution.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Queries for internal hostnames will be answered by the internal
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync servers, and queries for external hostnames will be forwarded back
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync out to the DNS servers on the bastion hosts.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync In order for all this to work properly, internal clients will
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync need to be configured to query <span class="emphasis"><em>only</em></span> the internal
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync name servers for DNS queries. This could also be enforced via
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync selective
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync filtering on the network.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync If everything has been set properly, <span class="emphasis"><em>Example, Inc.</em></span>'s
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync internal clients will now be able to:
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<li class="listitem">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Look up any hostnames in the <code class="literal">site1</code>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync and
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <code class="literal">site2.example.com</code> zones.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </li>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<li class="listitem">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Look up any hostnames in the <code class="literal">site1.internal</code> and
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <code class="literal">site2.internal</code> domains.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </li>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<li class="listitem">Look up any hostnames on the Internet.</li>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<li class="listitem">Exchange mail with both internal and external people.</li>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</ul></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Hosts on the Internet will be able to:
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<li class="listitem">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Look up any hostnames in the <code class="literal">site1</code>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync and
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <code class="literal">site2.example.com</code> zones.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </li>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<li class="listitem">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Exchange mail with anyone in the <code class="literal">site1</code> and
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <code class="literal">site2.example.com</code> zones.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </li>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</ul></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Here is an example configuration for the setup we just
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync described above. Note that this is only configuration information;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync for information on how to configure your zone files, see <a class="xref" href="Bv9ARM.ch03.html#sample_configuration" title="Sample Configurations">the section called &#8220;Sample Configurations&#8221;</a>.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Internal DNS server config:
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<pre class="programlisting">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsyncacl internals { 172.16.72.0/24; 192.168.1.0/24; };
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsyncacl externals { <code class="varname">bastion-ips-go-here</code>; };
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsyncoptions {
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync ...
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync ...
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync forward only;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync // forward to external servers
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync forwarders {
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <code class="varname">bastion-ips-go-here</code>;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync };
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync // sample allow-transfer (no one)
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync allow-transfer { none; };
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync // restrict query access
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync allow-query { internals; externals; };
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync // restrict recursion
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync allow-recursion { internals; };
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync ...
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync ...
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync};
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// sample master zone
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsynczone "site1.example.com" {
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync type master;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync file "m/site1.example.com";
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync // do normal iterative resolution (do not forward)
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync forwarders { };
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync allow-query { internals; externals; };
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync allow-transfer { internals; };
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync};
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// sample slave zone
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsynczone "site2.example.com" {
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync type slave;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync file "s/site2.example.com";
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync masters { 172.16.72.3; };
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync forwarders { };
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync allow-query { internals; externals; };
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync allow-transfer { internals; };
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync};
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsynczone "site1.internal" {
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync type master;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync file "m/site1.internal";
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync forwarders { };
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync allow-query { internals; };
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync allow-transfer { internals; }
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync};
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsynczone "site2.internal" {
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync type slave;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync file "s/site2.internal";
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync masters { 172.16.72.3; };
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync forwarders { };
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync allow-query { internals };
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync allow-transfer { internals; }
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync};
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</pre>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync External (bastion host) DNS server config:
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<pre class="programlisting">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsyncacl internals { 172.16.72.0/24; 192.168.1.0/24; };
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsyncacl externals { bastion-ips-go-here; };
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsyncoptions {
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync ...
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync ...
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync // sample allow-transfer (no one)
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync allow-transfer { none; };
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync // default query access
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync allow-query { any; };
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync // restrict cache access
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync allow-query-cache { internals; externals; };
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync // restrict recursion
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync allow-recursion { internals; externals; };
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync ...
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync ...
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync};
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync// sample slave zone
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsynczone "site1.example.com" {
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync type master;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync file "m/site1.foo.com";
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync allow-transfer { internals; externals; };
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync};
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsynczone "site2.example.com" {
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync type slave;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync file "s/site2.foo.com";
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync masters { another_bastion_host_maybe; };
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync allow-transfer { internals; externals; }
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync};
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</pre>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync In the <code class="filename">resolv.conf</code> (or equivalent) on
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the bastion host(s):
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<pre class="programlisting">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsyncsearch ...
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsyncnameserver 172.16.72.2
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsyncnameserver 172.16.72.3
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsyncnameserver 172.16.72.4
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</pre>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="titlepage"><div><div><h2 class="title" style="clear: both">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="tsig"></a>TSIG</h2></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync TSIG (Transaction SIGnatures) is a mechanism for authenticating DNS
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync messages, originally specified in RFC 2845. It allows DNS messages
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync to be cryptographically signed using a shared secret. TSIG can
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync be used in any DNS transaction, as a way to restrict access to
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync certain server functions (e.g., recursive queries) to authorized
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync clients when IP-based access control is insufficient or needs to
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync be overridden, or as a way to ensure message authenticity when it
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync is critical to the integrity of the server, such as with dynamic
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync UPDATE messages or zone transfers from a master to a slave server.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync This is a guide to setting up TSIG in <acronym class="acronym">BIND</acronym>.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync It describes the configuration syntax and the process of creating
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync TSIG keys.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>named</strong></span> supports TSIG for server-to-server
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync communication, and some of the tools included with
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <acronym class="acronym">BIND</acronym> support it for sending messages to
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>named</strong></span>:
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<li class="listitem">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a class="xref" href="man.nsupdate.html" title="nsupdate"><span class="refentrytitle"><span class="application">nsupdate</span></span>(1)</a> supports TSIG via the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <code class="option">-k</code>, <code class="option">-l</code> and
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <code class="option">-y</code> command line options, or via
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the <span class="command"><strong>key</strong></span> command when running
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync interactively.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </li>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<li class="listitem">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a class="xref" href="man.dig.html" title="dig"><span class="refentrytitle">dig</span>(1)</a> supports TSIG via the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <code class="option">-k</code> and <code class="option">-y</code> command
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync line options.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </li>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</ul></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="titlepage"><div><div><h3 class="title">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="id-1.5.6.5"></a>Generating a Shared Key</h3></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync TSIG keys can be generated using the <span class="command"><strong>tsig-keygen</strong></span>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync command; the output of the command is a <span class="command"><strong>key</strong></span> directive
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync suitable for inclusion in <code class="filename">named.conf</code>. The
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync key name, algorithm and size can be specified by command line parameters;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the defaults are "tsig-key", HMAC-SHA256, and 256 bits, respectively.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Any string which is a valid DNS name can be used as a key name.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync For example, a key to be shared between servers called
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="emphasis"><em>host1</em></span> and <span class="emphasis"><em>host2</em></span> could
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync be called "host1-host2.", and this key could be generated using:
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<pre class="programlisting">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync $ tsig-keygen host1-host2. &gt; host1-host2.key
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</pre>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync This key may then be copied to both hosts. The key name and secret
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync must be identical on both hosts.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync (Note: copying a shared secret from one server to another is beyond
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the scope of the DNS. A secure transport mechanism should be used:
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync secure FTP, SSL, ssh, telephone, encrypted email, etc.)
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>tsig-keygen</strong></span> can also be run as
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>ddns-confgen</strong></span>, in which case its output includes
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync additional configuration text for setting up dynamic DNS in
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>named</strong></span>. See <a class="xref" href="man.ddns-confgen.html" title="ddns-confgen"><span class="refentrytitle"><span class="application">ddns-confgen</span></span>(8)</a>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync for details.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="titlepage"><div><div><h3 class="title">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="id-1.5.6.6"></a>Loading A New Key</h3></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync For a key shared between servers called
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="emphasis"><em>host1</em></span> and <span class="emphasis"><em>host2</em></span>,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the following could be added to each server's
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <code class="filename">named.conf</code> file:
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<pre class="programlisting">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsynckey "host1-host2." {
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync algorithm hmac-sha256;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync secret "DAopyf1mhCbFVZw7pgmNPBoLUq8wEUT7UuPoLENP2HY=";
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync};
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</pre>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync (This is the same key generated above using
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>tsig-keygen</strong></span>.)
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Since this text contains a secret, it
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync is recommended that either <code class="filename">named.conf</code> not be
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync world-readable, or that the <span class="command"><strong>key</strong></span> directive
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync be stored in a file which is not world-readable, and which is
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync included in <code class="filename">named.conf</code> via the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>include</strong></span> directive.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Once a key has been added to <code class="filename">named.conf</code> and the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync server has been restarted or reconfigured, the server can recognize
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the key. If the server receives a message signed by the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync key, it will be able to verify the signature. If the signature
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync is valid, the response will be signed using the same key.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync TSIG keys that are known to a server can be listed using the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync command <span class="command"><strong>rndc tsig-list</strong></span>.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="titlepage"><div><div><h3 class="title">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="id-1.5.6.7"></a>Instructing the Server to Use a Key</h3></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync A server sending a request to another server must be told whether
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync to use a key, and if so, which key to use.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync For example, a key may be specified for each server in the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>masters</strong></span> statement in the definition of a
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync slave zone; in this case, all SOA QUERY messages, NOTIFY
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync messages, and zone transfer requests (AXFR or IXFR) will be
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync signed using the specified key. Keys may also be specified
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync in the <span class="command"><strong>also-notify</strong></span> statement of a master
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync or slave zone, causing NOTIFY messages to be signed using
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the specified key.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Keys can also be specified in a <span class="command"><strong>server</strong></span>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync directive. Adding the following on <span class="emphasis"><em>host1</em></span>,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync if the IP address of <span class="emphasis"><em>host2</em></span> is 10.1.2.3, would
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync cause <span class="emphasis"><em>all</em></span> requests from <span class="emphasis"><em>host1</em></span>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync to <span class="emphasis"><em>host2</em></span>, including normal DNS queries, to be
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync signed using the <span class="command"><strong>host1-host2.</strong></span> key:
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<pre class="programlisting">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsyncserver 10.1.2.3 {
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync keys { host1-host2. ;};
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync};
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</pre>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Multiple keys may be present in the <span class="command"><strong>keys</strong></span>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync statement, but only the first one is used. As this directive does
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync not contain secrets, it can be used in a world-readable file.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Requests sent by <span class="emphasis"><em>host2</em></span> to <span class="emphasis"><em>host1</em></span>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync would <span class="emphasis"><em>not</em></span> be signed, unless a similar
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>server</strong></span> directive were in <span class="emphasis"><em>host2</em></span>'s
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync configuration file.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Whenever any server sends a TSIG-signed DNS request, it will expect
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the response to be signed with the same key. If a response is not
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync signed, or if the signature is not valid, the response will be
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync rejected.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="titlepage"><div><div><h3 class="title">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="id-1.5.6.8"></a>TSIG-Based Access Control</h3></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync TSIG keys may be specified in ACL definitions and ACL directives
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync such as <span class="command"><strong>allow-query</strong></span>, <span class="command"><strong>allow-transfer</strong></span>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync and <span class="command"><strong>allow-update</strong></span>.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync The above key would be denoted in an ACL element as
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>key host1-host2.</strong></span>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync An example of an <span class="command"><strong>allow-update</strong></span> directive using
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync a TSIG key:
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<pre class="programlisting">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsyncallow-update { !{ !localnets; any; }; key host1-host2. ;};
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</pre>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync This allows dynamic updates to succeed only if the UPDATE
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync request comes from an address in <span class="command"><strong>localnets</strong></span>,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="emphasis"><em>and</em></span> if it is signed using the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>host1-host2.</strong></span> key.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync See <a class="xref" href="Bv9ARM.ch06.html#dynamic_update_policies" title="Dynamic Update Policies">the section called &#8220;Dynamic Update Policies&#8221;</a> for a discussion of
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the more flexible <span class="command"><strong>update-policy</strong></span> statement.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="titlepage"><div><div><h3 class="title">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="id-1.5.6.9"></a>Errors</h3></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Processing of TSIG-signed messages can result in several errors:
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<li class="listitem">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync If a TSIG-aware server receives a message signed by an
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync unknown key, the response will be unsigned, with the TSIG
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync extended error code set to BADKEY.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </li>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<li class="listitem">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync If a TSIG-aware server receives a message from a known key
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync but with an invalid signature, the response will be unsigned,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync with the TSIG extended error code set to BADSIG.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </li>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<li class="listitem">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync If a TSIG-aware server receives a message with a time
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync outside of the allowed range, the response will be signed, with
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the TSIG extended error code set to BADTIME, and the time values
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync will be adjusted so that the response can be successfully
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync verified.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </li>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</ul></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync In all of the above cases, the server will return a response code
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync of NOTAUTH (not authenticated).
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="titlepage"><div><div><h2 class="title" style="clear: both">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="tkey"></a>TKEY</h2></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync TKEY (Transaction KEY) is a mechanism for automatically negotiating
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync a shared secret between two hosts, originally specified in RFC 2930.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync There are several TKEY "modes" that specify how a key is to be
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync generated or assigned. <acronym class="acronym">BIND</acronym> 9 implements only
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync one of these modes: Diffie-Hellman key exchange. Both hosts are
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync required to have a KEY record with algorithm DH (though this
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync record is not required to be present in a zone).
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync The TKEY process is initiated by a client or server by sending
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync a query of type TKEY to a TKEY-aware server. The query must include
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync an appropriate KEY record in the additional section, and
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync must be signed using either TSIG or SIG(0) with a previously
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync established key. The server's response, if successful, will
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync contain a TKEY record in its answer section. After this transaction,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync both participants will have enough information to calculate a
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync shared secret using Diffie-Hellman key exchange. The shared secret
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync can then be used by to sign subsequent transactions between the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync two servers.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync TSIG keys known by the server, including TKEY-negotiated keys, can
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync be listed using <span class="command"><strong>rndc tsig-list</strong></span>.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync TKEY-negotiated keys can be deleted from a server using
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>rndc tsig-delete</strong></span>. This can also be done via
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the TKEY protocol itself, by sending an authenticated TKEY query
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync specifying the "key deletion" mode.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="titlepage"><div><div><h2 class="title" style="clear: both">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="sig0"></a>SIG(0)</h2></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <acronym class="acronym">BIND</acronym> partially supports DNSSEC SIG(0)
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync transaction signatures as specified in RFC 2535 and RFC 2931.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync SIG(0) uses public/private keys to authenticate messages. Access control
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync is performed in the same manner as TSIG keys; privileges can be
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync granted or denied in ACL directives based on the key name.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync When a SIG(0) signed message is received, it will only be
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync verified if the key is known and trusted by the server. The
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync server will not attempt to recursively fetch or validate the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync key.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync SIG(0) signing of multiple-message TCP streams is not supported.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync The only tool shipped with <acronym class="acronym">BIND</acronym> 9 that
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync generates SIG(0) signed messages is <span class="command"><strong>nsupdate</strong></span>.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="titlepage"><div><div><h2 class="title" style="clear: both">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="DNSSEC"></a>DNSSEC</h2></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Cryptographic authentication of DNS information is possible
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync through the DNS Security (<span class="emphasis"><em>DNSSEC-bis</em></span>) extensions,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync defined in RFC 4033, RFC 4034, and RFC 4035.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync This section describes the creation and use of DNSSEC signed zones.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync In order to set up a DNSSEC secure zone, there are a series
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync of steps which must be followed. <acronym class="acronym">BIND</acronym>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync 9 ships
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync with several tools
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync that are used in this process, which are explained in more detail
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync below. In all cases, the <code class="option">-h</code> option prints a
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync full list of parameters. Note that the DNSSEC tools require the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync keyset files to be in the working directory or the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync directory specified by the <code class="option">-d</code> option, and
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync that the tools shipped with BIND 9.2.x and earlier are not compatible
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync with the current ones.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync There must also be communication with the administrators of
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the parent and/or child zone to transmit keys. A zone's security
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync status must be indicated by the parent zone for a DNSSEC capable
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync resolver to trust its data. This is done through the presence
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync or absence of a <code class="literal">DS</code> record at the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync delegation
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync point.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync For other servers to trust data in this zone, they must
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync either be statically configured with this zone's zone key or the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync zone key of another zone above this one in the DNS tree.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="titlepage"><div><div><h3 class="title">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="dnssec_keys"></a>Generating Keys</h3></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync The <span class="command"><strong>dnssec-keygen</strong></span> program is used to
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync generate keys.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync A secure zone must contain one or more zone keys. The
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync zone keys will sign all other records in the zone, as well as
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the zone keys of any secure delegated zones. Zone keys must
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync have the same name as the zone, a name type of
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>ZONE</strong></span>, and must be usable for
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync authentication.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync It is recommended that zone keys use a cryptographic algorithm
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync designated as "mandatory to implement" by the IETF; currently
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the only one is RSASHA1.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync The following command will generate a 768-bit RSASHA1 key for
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the <code class="filename">child.example</code> zone:
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <strong class="userinput"><code>dnssec-keygen -a RSASHA1 -b 768 -n ZONE child.example.</code></strong>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Two output files will be produced:
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <code class="filename">Kchild.example.+005+12345.key</code> and
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <code class="filename">Kchild.example.+005+12345.private</code>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync (where
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync 12345 is an example of a key tag). The key filenames contain
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the key name (<code class="filename">child.example.</code>),
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync algorithm (3
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync is DSA, 1 is RSAMD5, 5 is RSASHA1, etc.), and the key tag (12345 in
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync this case).
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync The private key (in the <code class="filename">.private</code>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync file) is
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync used to generate signatures, and the public key (in the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <code class="filename">.key</code> file) is used for signature
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync verification.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync To generate another key with the same properties (but with
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync a different key tag), repeat the above command.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync The <span class="command"><strong>dnssec-keyfromlabel</strong></span> program is used
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync to get a key pair from a crypto hardware and build the key
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync files. Its usage is similar to <span class="command"><strong>dnssec-keygen</strong></span>.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync The public keys should be inserted into the zone file by
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync including the <code class="filename">.key</code> files using
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>$INCLUDE</strong></span> statements.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="titlepage"><div><div><h3 class="title">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="dnssec_signing"></a>Signing the Zone</h3></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync The <span class="command"><strong>dnssec-signzone</strong></span> program is used
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync to sign a zone.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Any <code class="filename">keyset</code> files corresponding to
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync secure subzones should be present. The zone signer will
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync generate <code class="literal">NSEC</code>, <code class="literal">NSEC3</code>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync and <code class="literal">RRSIG</code> records for the zone, as
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync well as <code class="literal">DS</code> for the child zones if
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <code class="literal">'-g'</code> is specified. If <code class="literal">'-g'</code>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync is not specified, then DS RRsets for the secure child
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync zones need to be added manually.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync The following command signs the zone, assuming it is in a
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync file called <code class="filename">zone.child.example</code>. By
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync default, all zone keys which have an available private key are
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync used to generate signatures.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <strong class="userinput"><code>dnssec-signzone -o child.example zone.child.example</code></strong>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync One output file is produced:
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <code class="filename">zone.child.example.signed</code>. This
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync file
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync should be referenced by <code class="filename">named.conf</code>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync as the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync input file for the zone.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p><span class="command"><strong>dnssec-signzone</strong></span>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync will also produce a keyset and dsset files and optionally a
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync dlvset file. These are used to provide the parent zone
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync administrators with the <code class="literal">DNSKEYs</code> (or their
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync corresponding <code class="literal">DS</code> records) that are the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync secure entry point to the zone.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="titlepage"><div><div><h3 class="title">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="dnssec_config"></a>Configuring Servers</h3></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync To enable <span class="command"><strong>named</strong></span> to respond appropriately
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync to DNS requests from DNSSEC aware clients,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>dnssec-enable</strong></span> must be set to yes.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync (This is the default setting.)
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync To enable <span class="command"><strong>named</strong></span> to validate answers from
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync other servers, the <span class="command"><strong>dnssec-enable</strong></span> option
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync must be set to <strong class="userinput"><code>yes</code></strong>, and the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>dnssec-validation</strong></span> options must be set to
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <strong class="userinput"><code>yes</code></strong> or <strong class="userinput"><code>auto</code></strong>.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync If <span class="command"><strong>dnssec-validation</strong></span> is set to
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <strong class="userinput"><code>auto</code></strong>, then a default
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync trust anchor for the DNS root zone will be used.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync If it is set to <strong class="userinput"><code>yes</code></strong>, however,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync then at least one trust anchor must be configured
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync with a <span class="command"><strong>trusted-keys</strong></span> or
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>managed-keys</strong></span> statement in
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <code class="filename">named.conf</code>, or DNSSEC validation
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync will not occur. The default setting is
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <strong class="userinput"><code>yes</code></strong>.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>trusted-keys</strong></span> are copies of DNSKEY RRs
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync for zones that are used to form the first link in the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync cryptographic chain of trust. All keys listed in
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>trusted-keys</strong></span> (and corresponding zones)
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync are deemed to exist and only the listed keys will be used
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync to validated the DNSKEY RRset that they are from.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>managed-keys</strong></span> are trusted keys which are
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync automatically kept up to date via RFC 5011 trust anchor
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync maintenance.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>trusted-keys</strong></span> and
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>managed-keys</strong></span> are described in more detail
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync later in this document.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Unlike <acronym class="acronym">BIND</acronym> 8, <acronym class="acronym">BIND</acronym>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync 9 does not verify signatures on load, so zone keys for
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync authoritative zones do not need to be specified in the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync configuration file.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync After DNSSEC gets established, a typical DNSSEC configuration
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync will look something like the following. It has one or
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync more public keys for the root. This allows answers from
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync outside the organization to be validated. It will also
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync have several keys for parts of the namespace the organization
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync controls. These are here to ensure that <span class="command"><strong>named</strong></span>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync is immune to compromises in the DNSSEC components of the security
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync of parent zones.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<pre class="programlisting">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsyncmanaged-keys {
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync /* Root Key */
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync "." initial-key 257 3 3 "BNY4wrWM1nCfJ+CXd0rVXyYmobt7sEEfK3clRbGaTwS
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync JxrGkxJWoZu6I7PzJu/E9gx4UC1zGAHlXKdE4zYIpRh
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync aBKnvcC2U9mZhkdUpd1Vso/HAdjNe8LmMlnzY3zy2Xy
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync 4klWOADTPzSv9eamj8V18PHGjBLaVtYvk/ln5ZApjYg
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync hf+6fElrmLkdaz MQ2OCnACR817DF4BBa7UR/beDHyp
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync 5iWTXWSi6XmoJLbG9Scqc7l70KDqlvXR3M/lUUVRbke
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync g1IPJSidmK3ZyCllh4XSKbje/45SKucHgnwU5jefMtq
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync 66gKodQj+MiA21AfUVe7u99WzTLzY3qlxDhxYQQ20FQ
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync 97S+LKUTpQcq27R7AT3/V5hRQxScINqwcz4jYqZD2fQ
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync dgxbcDTClU0CRBdiieyLMNzXG3";
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync};
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsynctrusted-keys {
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync /* Key for our organization's forward zone */
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync example.com. 257 3 5 "AwEAAaxPMcR2x0HbQV4WeZB6oEDX+r0QM6
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync 5KbhTjrW1ZaARmPhEZZe3Y9ifgEuq7vZ/z
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync GZUdEGNWy+JZzus0lUptwgjGwhUS1558Hb
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync 4JKUbbOTcM8pwXlj0EiX3oDFVmjHO444gL
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync kBOUKUf/mC7HvfwYH/Be22GnClrinKJp1O
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync g4ywzO9WglMk7jbfW33gUKvirTHr25GL7S
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync TQUzBb5Usxt8lgnyTUHs1t3JwCY5hKZ6Cq
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync FxmAVZP20igTixin/1LcrgX/KMEGd/biuv
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync F4qJCyduieHukuY3H4XMAcR+xia2nIUPvm
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync /oyWR8BW/hWdzOvnSCThlHf3xiYleDbt/o
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync 1OTQ09A0=";
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync /* Key for our reverse zone. */
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync 2.0.192.IN-ADDRPA.NET. 257 3 5 "AQOnS4xn/IgOUpBPJ3bogzwc
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync xOdNax071L18QqZnQQQAVVr+i
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync LhGTnNGp3HoWQLUIzKrJVZ3zg
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync gy3WwNT6kZo6c0tszYqbtvchm
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync gQC8CzKojM/W16i6MG/eafGU3
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync siaOdS0yOI6BgPsw+YZdzlYMa
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync IJGf4M4dyoKIhzdZyQ2bYQrjy
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Q4LB0lC7aOnsMyYKHHYeRvPxj
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync IQXmdqgOJGq+vsevG06zW+1xg
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync YJh9rCIfnm1GX/KMgxLPG2vXT
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync D/RnLX+D3T3UL7HJYHJhAZD5L
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync 59VvjSPsZJHeDCUyWYrvPZesZ
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync DIRvhDD52SKvbheeTJUm6Ehkz
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync ytNN2SN96QRk8j/iI8ib";
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync};
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsyncoptions {
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync ...
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync dnssec-enable yes;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync dnssec-validation yes;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync};
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</pre>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<h3 class="title">Note</h3>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync None of the keys listed in this example are valid. In particular,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the root key is not valid.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync When DNSSEC validation is enabled and properly configured,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the resolver will reject any answers from signed, secure zones
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync which fail to validate, and will return SERVFAIL to the client.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Responses may fail to validate for any of several reasons,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync including missing, expired, or invalid signatures, a key which
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync does not match the DS RRset in the parent zone, or an insecure
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync response from a zone which, according to its parent, should have
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync been secure.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<h3 class="title">Note</h3>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync When the validator receives a response from an unsigned zone
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync that has a signed parent, it must confirm with the parent
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync that the zone was intentionally left unsigned. It does
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync this by verifying, via signed and validated NSEC/NSEC3 records,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync that the parent zone contains no DS records for the child.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync If the validator <span class="emphasis"><em>can</em></span> prove that the zone
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync is insecure, then the response is accepted. However, if it
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync cannot, then it must assume an insecure response to be a
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync forgery; it rejects the response and logs an error.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync The logged error reads "insecurity proof failed" and
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync "got insecure response; parent indicates it should be secure".
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync (Prior to BIND 9.7, the logged error was "not insecure".
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync This referred to the zone, not the response.)
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="titlepage"><div><div><h2 class="title" style="clear: both">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="dnssec.dynamic.zones"></a>DNSSEC, Dynamic Zones, and Automatic Signing</h2></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>As of BIND 9.7.0 it is possible to change a dynamic zone
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync from insecure to signed and back again. A secure zone can use
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync either NSEC or NSEC3 chains.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section"><div class="titlepage"><div><div><h3 class="title">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="id-1.5.10.3"></a>Converting from insecure to secure</h3></div></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>Changing a zone from insecure to secure can be done in two
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync ways: using a dynamic DNS update, or the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>auto-dnssec</strong></span> zone option.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>For either method, you need to configure
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>named</strong></span> so that it can see the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <code class="filename">K*</code> files which contain the public and private
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync parts of the keys that will be used to sign the zone. These files
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync will have been generated by
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>dnssec-keygen</strong></span>. You can do this by placing them
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync in the key-directory, as specified in
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <code class="filename">named.conf</code>:</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<pre class="programlisting">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync zone example.net {
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync type master;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync update-policy local;
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync file "dynamic/example.net/example.net";
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync key-directory "dynamic/example.net";
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync };
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</pre>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>If one KSK and one ZSK DNSKEY key have been generated, this
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync configuration will cause all records in the zone to be signed
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync with the ZSK, and the DNSKEY RRset to be signed with the KSK as
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync well. An NSEC chain will be generated as part of the initial
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync signing process.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section"><div class="titlepage"><div><div><h3 class="title">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="id-1.5.10.8"></a>Dynamic DNS update method</h3></div></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>To insert the keys via dynamic update:</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<pre class="screen">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync % nsupdate
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync &gt; ttl 3600
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync &gt; update add example.net DNSKEY 256 3 7 AwEAAZn17pUF0KpbPA2c7Gz76Vb18v0teKT3EyAGfBfL8eQ8al35zz3Y I1m/SAQBxIqMfLtIwqWPdgthsu36azGQAX8=
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync &gt; update add example.net DNSKEY 257 3 7 AwEAAd/7odU/64o2LGsifbLtQmtO8dFDtTAZXSX2+X3e/UNlq9IHq3Y0 XtC0Iuawl/qkaKVxXe2lo8Ct+dM6UehyCqk=
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync &gt; send
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</pre>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>While the update request will complete almost immediately,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the zone will not be completely signed until
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>named</strong></span> has had time to walk the zone and
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync generate the NSEC and RRSIG records. The NSEC record at the apex
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync will be added last, to signal that there is a complete NSEC
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync chain.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>If you wish to sign using NSEC3 instead of NSEC, you should
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync add an NSEC3PARAM record to the initial update request. If you
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync wish the NSEC3 chain to have the OPTOUT bit set, set it in the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync flags field of the NSEC3PARAM record.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<pre class="screen">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync % nsupdate
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync &gt; ttl 3600
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync &gt; update add example.net DNSKEY 256 3 7 AwEAAZn17pUF0KpbPA2c7Gz76Vb18v0teKT3EyAGfBfL8eQ8al35zz3Y I1m/SAQBxIqMfLtIwqWPdgthsu36azGQAX8=
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync &gt; update add example.net DNSKEY 257 3 7 AwEAAd/7odU/64o2LGsifbLtQmtO8dFDtTAZXSX2+X3e/UNlq9IHq3Y0 XtC0Iuawl/qkaKVxXe2lo8Ct+dM6UehyCqk=
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync &gt; update add example.net NSEC3PARAM 1 1 100 1234567890
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync &gt; send
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</pre>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>Again, this update request will complete almost
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync immediately; however, the record won't show up until
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>named</strong></span> has had a chance to build/remove the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync relevant chain. A private type record will be created to record
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the state of the operation (see below for more details), and will
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync be removed once the operation completes.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>While the initial signing and NSEC/NSEC3 chain generation
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync is happening, other updates are possible as well.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section"><div class="titlepage"><div><div><h3 class="title">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="id-1.5.10.16"></a>Fully automatic zone signing</h3></div></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>To enable automatic signing, add the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>auto-dnssec</strong></span> option to the zone statement in
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <code class="filename">named.conf</code>.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>auto-dnssec</strong></span> has two possible arguments:
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <code class="constant">allow</code> or
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <code class="constant">maintain</code>.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>With
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>auto-dnssec allow</strong></span>,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>named</strong></span> can search the key directory for keys
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync matching the zone, insert them into the zone, and use them to
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync sign the zone. It will do so only when it receives an
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>rndc sign &lt;zonename&gt;</strong></span>.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>auto-dnssec maintain</strong></span> includes the above
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync functionality, but will also automatically adjust the zone's
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync DNSKEY records on schedule according to the keys' timing metadata.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync (See <a class="xref" href="man.dnssec-keygen.html" title="dnssec-keygen"><span class="refentrytitle"><span class="application">dnssec-keygen</span></span>(8)</a> and
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <a class="xref" href="man.dnssec-settime.html" title="dnssec-settime"><span class="refentrytitle"><span class="application">dnssec-settime</span></span>(8)</a> for more information.)
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>named</strong></span> will periodically search the key directory
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync for keys matching the zone, and if the keys' metadata indicates
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync that any change should be made the zone, such as adding, removing,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync or revoking a key, then that action will be carried out. By default,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the key directory is checked for changes every 60 minutes; this period
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync can be adjusted with the <code class="option">dnssec-loadkeys-interval</code>, up
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync to a maximum of 24 hours. The <span class="command"><strong>rndc loadkeys</strong></span> forces
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>named</strong></span> to check for key updates immediately.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync If keys are present in the key directory the first time the zone
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync is loaded, the zone will be signed immediately, without waiting for an
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>rndc sign</strong></span> or <span class="command"><strong>rndc loadkeys</strong></span>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync command. (Those commands can still be used when there are unscheduled
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync key changes, however.)
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync When new keys are added to a zone, the TTL is set to match that
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync of any existing DNSKEY RRset. If there is no existing DNSKEY RRset,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync then the TTL will be set to the TTL specified when the key was
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync created (using the <span class="command"><strong>dnssec-keygen -L</strong></span> option), if
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync any, or to the SOA TTL.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync If you wish the zone to be signed using NSEC3 instead of NSEC,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync submit an NSEC3PARAM record via dynamic update prior to the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync scheduled publication and activation of the keys. If you wish the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync NSEC3 chain to have the OPTOUT bit set, set it in the flags field
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync of the NSEC3PARAM record. The NSEC3PARAM record will not appear in
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the zone immediately, but it will be stored for later reference. When
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the zone is signed and the NSEC3 chain is completed, the NSEC3PARAM
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync record will appear in the zone.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>Using the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>auto-dnssec</strong></span> option requires the zone to be
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync configured to allow dynamic updates, by adding an
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>allow-update</strong></span> or
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>update-policy</strong></span> statement to the zone
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync configuration. If this has not been done, the configuration will
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync fail.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section"><div class="titlepage"><div><div><h3 class="title">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="id-1.5.10.25"></a>Private-type records</h3></div></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>The state of the signing process is signaled by
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync private-type records (with a default type value of 65534). When
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync signing is complete, these records will have a nonzero value for
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the final octet (for those records which have a nonzero initial
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync octet).</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>The private type record format: If the first octet is
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync non-zero then the record indicates that the zone needs to be
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync signed with the key matching the record, or that all signatures
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync that match the record should be removed.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="literallayout"><p><br>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<br>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync��algorithm�(octet�1)<br>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync��key�id�in�network�order�(octet�2�and�3)<br>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync��removal�flag�(octet�4)<br>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync��complete�flag�(octet�5)<br>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</p></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>Only records flagged as "complete" can be removed via
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync dynamic update. Attempts to remove other private type records
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync will be silently ignored.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>If the first octet is zero (this is a reserved algorithm
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync number that should never appear in a DNSKEY record) then the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync record indicates changes to the NSEC3 chains are in progress. The
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync rest of the record contains an NSEC3PARAM record. The flag field
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync tells what operation to perform based on the flag bits.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="literallayout"><p><br>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<br>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync��0x01�OPTOUT<br>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync��0x80�CREATE<br>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync��0x40�REMOVE<br>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync��0x20�NONSEC<br>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</p></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section"><div class="titlepage"><div><div><h3 class="title">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="id-1.5.10.32"></a>DNSKEY rollovers</h3></div></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>As with insecure-to-secure conversions, rolling DNSSEC
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync keys can be done in two ways: using a dynamic DNS update, or the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>auto-dnssec</strong></span> zone option.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section"><div class="titlepage"><div><div><h3 class="title">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="id-1.5.10.34"></a>Dynamic DNS update method</h3></div></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p> To perform key rollovers via dynamic update, you need to add
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the <code class="filename">K*</code> files for the new keys so that
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>named</strong></span> can find them. You can then add the new
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync DNSKEY RRs via dynamic update.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>named</strong></span> will then cause the zone to be signed
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync with the new keys. When the signing is complete the private type
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync records will be updated so that the last octet is non
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync zero.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>If this is for a KSK you need to inform the parent and any
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync trust anchor repositories of the new KSK.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>You should then wait for the maximum TTL in the zone before
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync removing the old DNSKEY. If it is a KSK that is being updated,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync you also need to wait for the DS RRset in the parent to be
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync updated and its TTL to expire. This ensures that all clients will
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync be able to verify at least one signature when you remove the old
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync DNSKEY.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>The old DNSKEY can be removed via UPDATE. Take care to
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync specify the correct key.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>named</strong></span> will clean out any signatures generated
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync by the old key after the update completes.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section"><div class="titlepage"><div><div><h3 class="title">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="id-1.5.10.39"></a>Automatic key rollovers</h3></div></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>When a new key reaches its activation date (as set by
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>dnssec-keygen</strong></span> or <span class="command"><strong>dnssec-settime</strong></span>),
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync if the <span class="command"><strong>auto-dnssec</strong></span> zone option is set to
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <code class="constant">maintain</code>, <span class="command"><strong>named</strong></span> will
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync automatically carry out the key rollover. If the key's algorithm
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync has not previously been used to sign the zone, then the zone will
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync be fully signed as quickly as possible. However, if the new key
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync is replacing an existing key of the same algorithm, then the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync zone will be re-signed incrementally, with signatures from the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync old key being replaced with signatures from the new key as their
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync signature validity periods expire. By default, this rollover
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync completes in 30 days, after which it will be safe to remove the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync old key from the DNSKEY RRset.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section"><div class="titlepage"><div><div><h3 class="title">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="id-1.5.10.41"></a>NSEC3PARAM rollovers via UPDATE</h3></div></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>Add the new NSEC3PARAM record via dynamic update. When the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync new NSEC3 chain has been generated, the NSEC3PARAM flag field
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync will be zero. At this point you can remove the old NSEC3PARAM
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync record. The old chain will be removed after the update request
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync completes.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section"><div class="titlepage"><div><div><h3 class="title">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="id-1.5.10.43"></a>Converting from NSEC to NSEC3</h3></div></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>To do this, you just need to add an NSEC3PARAM record. When
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the conversion is complete, the NSEC chain will have been removed
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync and the NSEC3PARAM record will have a zero flag field. The NSEC3
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync chain will be generated before the NSEC chain is
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync destroyed.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section"><div class="titlepage"><div><div><h3 class="title">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="id-1.5.10.45"></a>Converting from NSEC3 to NSEC</h3></div></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>To do this, use <span class="command"><strong>nsupdate</strong></span> to
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync remove all NSEC3PARAM records with a zero flag
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync field. The NSEC chain will be generated before the NSEC3 chain is
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync removed.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section"><div class="titlepage"><div><div><h3 class="title">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="id-1.5.10.47"></a>Converting from secure to insecure</h3></div></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>To convert a signed zone to unsigned using dynamic DNS,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync delete all the DNSKEY records from the zone apex using
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>nsupdate</strong></span>. All signatures, NSEC or NSEC3 chains,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync and associated NSEC3PARAM records will be removed automatically.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync This will take place after the update request completes.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p> This requires the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>dnssec-secure-to-insecure</strong></span> option to be set to
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <strong class="userinput"><code>yes</code></strong> in
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <code class="filename">named.conf</code>.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>In addition, if the <span class="command"><strong>auto-dnssec maintain</strong></span>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync zone statement is used, it should be removed or changed to
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>allow</strong></span> instead (or it will re-sign).
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section"><div class="titlepage"><div><div><h3 class="title">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="id-1.5.10.51"></a>Periodic re-signing</h3></div></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>In any secure zone which supports dynamic updates, <span class="command"><strong>named</strong></span>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync will periodically re-sign RRsets which have not been re-signed as
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync a result of some update action. The signature lifetimes will be
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync adjusted so as to spread the re-sign load over time rather than
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync all at once.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section"><div class="titlepage"><div><div><h3 class="title">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="id-1.5.10.53"></a>NSEC3 and OPTOUT</h3></div></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>named</strong></span> only supports creating new NSEC3 chains
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync where all the NSEC3 records in the zone have the same OPTOUT
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync state.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>named</strong></span> supports UPDATES to zones where the NSEC3
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync records in the chain have mixed OPTOUT state.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>named</strong></span> does not support changing the OPTOUT
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync state of an individual NSEC3 record, the entire chain needs to be
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync changed if the OPTOUT state of an individual NSEC3 needs to be
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync changed.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="titlepage"><div><div><h2 class="title" style="clear: both">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="rfc5011.support"></a>Dynamic Trust Anchor Management</h2></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>BIND 9.7.0 introduces support for RFC 5011, dynamic trust
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync anchor management. Using this feature allows
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>named</strong></span> to keep track of changes to critical
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync DNSSEC keys without any need for the operator to make changes to
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync configuration files.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="titlepage"><div><div><h3 class="title">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="id-1.5.11.3"></a>Validating Resolver</h3></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>To configure a validating resolver to use RFC 5011 to
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync maintain a trust anchor, configure the trust anchor using a
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>managed-keys</strong></span> statement. Information about
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync this can be found in
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <a class="xref" href="Bv9ARM.ch06.html#managed-keys" title="managed-keys Statement Definition and Usage">the section called &#8220;<span class="command"><strong>managed-keys</strong></span> Statement Definition
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync and Usage&#8221;</a>.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="titlepage"><div><div><h3 class="title">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="id-1.5.11.4"></a>Authoritative Server</h3></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>To set up an authoritative zone for RFC 5011 trust anchor
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync maintenance, generate two (or more) key signing keys (KSKs) for
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the zone. Sign the zone with one of them; this is the "active"
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync KSK. All KSKs which do not sign the zone are "stand-by"
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync keys.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>Any validating resolver which is configured to use the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync active KSK as an RFC 5011-managed trust anchor will take note
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync of the stand-by KSKs in the zone's DNSKEY RRset, and store them
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync for future reference. The resolver will recheck the zone
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync periodically, and after 30 days, if the new key is still there,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync then the key will be accepted by the resolver as a valid trust
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync anchor for the zone. Any time after this 30-day acceptance
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync timer has completed, the active KSK can be revoked, and the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync zone can be "rolled over" to the newly accepted key.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>The easiest way to place a stand-by key in a zone is to
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync use the "smart signing" features of
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>dnssec-keygen</strong></span> and
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>dnssec-signzone</strong></span>. If a key with a publication
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync date in the past, but an activation date which is unset or in
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync the future, "
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>dnssec-signzone -S</strong></span>" will include the DNSKEY
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync record in the zone, but will not sign with it:</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<pre class="screen">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync$ <strong class="userinput"><code>dnssec-keygen -K keys -f KSK -P now -A now+2y example.net</code></strong>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync$ <strong class="userinput"><code>dnssec-signzone -S -K keys example.net</code></strong>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</pre>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>To revoke a key, the new command
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>dnssec-revoke</strong></span> has been added. This adds the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync REVOKED bit to the key flags and re-generates the
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <code class="filename">K*.key</code> and
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <code class="filename">K*.private</code> files.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>After revoking the active key, the zone must be signed
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync with both the revoked KSK and the new active KSK. (Smart
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync signing takes care of this automatically.)</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>Once a key has been revoked and used to sign the DNSKEY
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync RRset in which it appears, that key will never again be
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync accepted as a valid trust anchor by the resolver. However,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync validation can proceed using the new active key (which had been
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync accepted by the resolver when it was a stand-by key).</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>See RFC 5011 for more details on key rollover
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync scenarios.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>When a key has been revoked, its key ID changes,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync increasing by 128, and wrapping around at 65535. So, for
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync example, the key "<code class="filename">Kexample.com.+005+10000</code>" becomes
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync "<code class="filename">Kexample.com.+005+10128</code>".</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>If two keys have IDs exactly 128 apart, and one is
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync revoked, then the two key IDs will collide, causing several
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync problems. To prevent this,
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync <span class="command"><strong>dnssec-keygen</strong></span> will not generate a new key if
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync another key is present which may collide. This checking will
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync only occur if the new keys are written to the same directory
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync which holds all other keys in use for that zone.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>Older versions of BIND 9 did not have this precaution.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync Exercise caution if using key revocation on keys that were
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync generated by previous releases, or if using keys stored in
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync multiple directories or on multiple machines.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>It is expected that a future release of BIND 9 will
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync address this problem in a different way, by storing revoked
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync keys with their original unrevoked key IDs.</p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync</div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="section">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<div class="titlepage"><div><div><h2 class="title" style="clear: both">
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<a name="pkcs11"></a>PKCS#11 (Cryptoki) support</h2></div></div></div>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync PKCS#11 (Public Key Cryptography Standard #11) defines a
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync platform-independent API for the control of hardware security
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync modules (HSMs) and other cryptographic support devices.
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync </p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync<p>
4fd606d1f5abe38e1f42c38de1d2e895166bd0f4vboxsync BIND 9 is known to work with three HSMs: The AEP Keyper, which has
been tested with Debian Linux, Solaris x86 and Windows Server 2003;
the Thales nShield, tested with Debian Linux; and the Sun SCA 6000
cryptographic acceleration board, tested with Solaris x86. In
addition, BIND can be used with all current versions of SoftHSM,
a software-based HSM simulator library produced by the OpenDNSSEC
project.
</p>
<p>
PKCS#11 makes use of a "provider library": a dynamically loadable
library which provides a low-level PKCS#11 interface to drive the HSM
hardware. The PKCS#11 provider library comes from the HSM vendor, and
it is specific to the HSM to be controlled.
</p>
<p>
There are two available mechanisms for PKCS#11 support in BIND 9:
OpenSSL-based PKCS#11 and native PKCS#11. When using the first
mechanism, BIND uses a modified version of OpenSSL, which loads
the provider library and operates the HSM indirectly; any
cryptographic operations not supported by the HSM can be carried
out by OpenSSL instead. The second mechanism enables BIND to bypass
OpenSSL completely; BIND loads the provider library itself, and uses
the PKCS#11 API to drive the HSM directly.
</p>
<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="id-1.5.12.6"></a>Prerequisites</h3></div></div></div>
<p>
See the documentation provided by your HSM vendor for
information about installing, initializing, testing and
troubleshooting the HSM.
</p>
</div>
<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="id-1.5.12.7"></a>Native PKCS#11</h3></div></div></div>
<p>
Native PKCS#11 mode will only work with an HSM capable of carrying
out <span class="emphasis"><em>every</em></span> cryptographic operation BIND 9 may
need. The HSM's provider library must have a complete implementation
of the PKCS#11 API, so that all these functions are accessible. As of
this writing, only the Thales nShield HSM and SoftHSMv2 can be used
in this fashion. For other HSMs, including the AEP Keyper, Sun SCA
6000 and older versions of SoftHSM, use OpenSSL-based PKCS#11.
(Note: Eventually, when more HSMs become capable of supporting
native PKCS#11, it is expected that OpenSSL-based PKCS#11 will
be deprecated.)
</p>
<p>
To build BIND with native PKCS#11, configure as follows:
</p>
<pre class="screen">
$ <strong class="userinput"><code>cd bind9</code></strong>
$ <strong class="userinput"><code>/configure --enable-native-pkcs11 \
--with-pkcs11=<em class="replaceable"><code>provider-library-path</code></em></code></strong>
</pre>
<p>
This will cause all BIND tools, including <span class="command"><strong>named</strong></span>
and the <span class="command"><strong>dnssec-*</strong></span> and <span class="command"><strong>pkcs11-*</strong></span>
tools, to use the PKCS#11 provider library specified in
<em class="replaceable"><code>provider-library-path</code></em> for cryptography.
(The provider library path can be overridden using the
<code class="option">-E</code> in <span class="command"><strong>named</strong></span> and the
<span class="command"><strong>dnssec-*</strong></span> tools, or the <code class="option">-m</code> in
the <span class="command"><strong>pkcs11-*</strong></span> tools.)
</p>
<div class="section">
<div class="titlepage"><div><div><h4 class="title">
<a name="id-1.5.12.7.6"></a>Building SoftHSMv2</h4></div></div></div>
<p>
SoftHSMv2, the latest development version of SoftHSM, is available
from
<a class="link" href="https://github.com/opendnssec/SoftHSMv2" target="_top">
https://github.com/opendnssec/SoftHSMv2
</a>.
It is a software library developed by the OpenDNSSEC project
(<a class="link" href="http://www.opendnssec.org" target="_top">
http://www.opendnssec.org
</a>)
which provides a PKCS#11 interface to a virtual HSM, implemented in
the form of a SQLite3 database on the local filesystem. It provides
less security than a true HSM, but it allows you to experiment with
native PKCS#11 when an HSM is not available. SoftHSMv2 can be
configured to use either OpenSSL or the Botan library to perform
cryptographic functions, but when using it for native PKCS#11 in
BIND, OpenSSL is required.
</p>
<p>
By default, the SoftHSMv2 configuration file is
<em class="replaceable"><code>prefix</code></em>/etc/softhsm2.conf (where
<em class="replaceable"><code>prefix</code></em> is configured at compile time).
This location can be overridden by the SOFTHSM2_CONF environment
variable. The SoftHSMv2 cryptographic store must be installed and
initialized before using it with BIND.
</p>
<pre class="screen">
$ <strong class="userinput"><code> cd SoftHSMv2 </code></strong>
$ <strong class="userinput"><code> configure --with-crypto-backend=openssl --prefix=/opt/pkcs11/usr --enable-gost </code></strong>
$ <strong class="userinput"><code> make </code></strong>
$ <strong class="userinput"><code> make install </code></strong>
$ <strong class="userinput"><code> /opt/pkcs11/usr/bin/softhsm-util --init-token 0 --slot 0 --label softhsmv2 </code></strong>
</pre>
</div>
</div>
<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="id-1.5.12.8"></a>OpenSSL-based PKCS#11</h3></div></div></div>
<p>
OpenSSL-based PKCS#11 mode uses a modified version of the
OpenSSL library; stock OpenSSL does not fully support PKCS#11.
ISC provides a patch to OpenSSL to correct this. This patch is
based on work originally done by the OpenSolaris project; it has been
modified by ISC to provide new features such as PIN management and
key-by-reference.
</p>
<p>
There are two "flavors" of PKCS#11 support provided by
the patched OpenSSL, one of which must be chosen at
configuration time. The correct choice depends on the HSM
hardware:
</p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem"><p>
Use 'crypto-accelerator' with HSMs that have hardware
cryptographic acceleration features, such as the SCA 6000
board. This causes OpenSSL to run all supported
cryptographic operations in the HSM.
</p></li>
<li class="listitem"><p>
Use 'sign-only' with HSMs that are designed to
function primarily as secure key storage devices, but lack
hardware acceleration. These devices are highly secure, but
are not necessarily any faster at cryptography than the
system CPU &#8212; often, they are slower. It is therefore
most efficient to use them only for those cryptographic
functions that require access to the secured private key,
such as zone signing, and to use the system CPU for all
other computationally-intensive operations. The AEP Keyper
is an example of such a device.
</p></li>
</ul></div>
<p>
The modified OpenSSL code is included in the BIND 9 release,
in the form of a context diff against the latest versions of
OpenSSL. OpenSSL 0.9.8, 1.0.0, 1.0.1 and 1.0.2 are supported;
there are separate diffs for each version. In the examples to
follow, we use OpenSSL 0.9.8, but the same methods work with
OpenSSL 1.0.0 through 1.0.2.
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<h3 class="title">Note</h3>
<p>
The OpenSSL patches as of this writing (January 2016)
support versions 0.9.8zh, 1.0.0t, 1.0.1q and 1.0.2f.
ISC will provide updated patches as new versions of OpenSSL
are released. The version number in the following examples
is expected to change.
</p>
</div>
<p>
Before building BIND 9 with PKCS#11 support, it will be
necessary to build OpenSSL with the patch in place, and configure
it with the path to your HSM's PKCS#11 provider library.
</p>
<div class="section">
<div class="titlepage"><div><div><h4 class="title">
<a name="id-1.5.12.8.8"></a>Patching OpenSSL</h4></div></div></div>
<pre class="screen">
$ <strong class="userinput"><code>wget <a class="link" href="" target="_top">http://www.openssl.org/source/openssl-0.9.8zc.tar.gz</a></code></strong>
</pre>
<p>Extract the tarball:</p>
<pre class="screen">
$ <strong class="userinput"><code>tar zxf openssl-0.9.8zc.tar.gz</code></strong>
</pre>
<p>Apply the patch from the BIND 9 release:</p>
<pre class="screen">
$ <strong class="userinput"><code>patch -p1 -d openssl-0.9.8zc \
&lt; bind9/bin/pkcs11/openssl-0.9.8zc-patch</code></strong>
</pre>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<h3 class="title">Note</h3>
<p>
The patch file may not be compatible with the
"patch" utility on all operating systems. You may need to
install GNU patch.
</p>
</div>
<p>
When building OpenSSL, place it in a non-standard
location so that it does not interfere with OpenSSL libraries
elsewhere on the system. In the following examples, we choose
to install into "/opt/pkcs11/usr". We will use this location
when we configure BIND 9.
</p>
<p>
Later, when building BIND 9, the location of the custom-built
OpenSSL library will need to be specified via configure.
</p>
</div>
<div class="section">
<div class="titlepage"><div><div><h4 class="title">
<a name="id-1.5.12.8.9"></a>Building OpenSSL for the AEP Keyper on Linux</h4></div></div></div>
<p>
The AEP Keyper is a highly secure key storage device,
but does not provide hardware cryptographic acceleration. It
can carry out cryptographic operations, but it is probably
slower than your system's CPU. Therefore, we choose the
'sign-only' flavor when building OpenSSL.
</p>
<p>
The Keyper-specific PKCS#11 provider library is
delivered with the Keyper software. In this example, we place
it /opt/pkcs11/usr/lib:
</p>
<pre class="screen">
$ <strong class="userinput"><code>cp pkcs11.GCC4.0.2.so.4.05 /opt/pkcs11/usr/lib/libpkcs11.so</code></strong>
</pre>
<p>
The Keyper library requires threads, so we
must specify -pthread.
</p>
<pre class="screen">
$ <strong class="userinput"><code>cd openssl-0.9.8zc</code></strong>
$ <strong class="userinput"><code>/Configure linux-x86_64 -pthread \
--pk11-libname=/opt/pkcs11/usr/lib/libpkcs11.so \
--pk11-flavor=sign-only \
--prefix=/opt/pkcs11/usr</code></strong>
</pre>
<p>
After configuring, run "<span class="command"><strong>make</strong></span>"
and "<span class="command"><strong>make test</strong></span>". If "<span class="command"><strong>make
test</strong></span>" fails with "pthread_atfork() not found", you forgot to
add the -pthread above.
</p>
</div>
<div class="section">
<div class="titlepage"><div><div><h4 class="title">
<a name="id-1.5.12.8.10"></a>Building OpenSSL for the SCA 6000 on Solaris</h4></div></div></div>
<p>
The SCA-6000 PKCS#11 provider is installed as a system
library, libpkcs11. It is a true crypto accelerator, up to 4
times faster than any CPU, so the flavor shall be
'crypto-accelerator'.
</p>
<p>
In this example, we are building on Solaris x86 on an
AMD64 system.
</p>
<pre class="screen">
$ <strong class="userinput"><code>cd openssl-0.9.8zc</code></strong>
$ <strong class="userinput"><code>/Configure solaris64-x86_64-cc \
--pk11-libname=/usr/lib/64/libpkcs11.so \
--pk11-flavor=crypto-accelerator \
--prefix=/opt/pkcs11/usr</code></strong>
</pre>
<p>
(For a 32-bit build, use "solaris-x86-cc" and /usr/lib/libpkcs11.so.)
</p>
<p>
After configuring, run
<span class="command"><strong>make</strong></span> and
<span class="command"><strong>make test</strong></span>.
</p>
</div>
<div class="section">
<div class="titlepage"><div><div><h4 class="title">
<a name="id-1.5.12.8.11"></a>Building OpenSSL for SoftHSM</h4></div></div></div>
<p>
SoftHSM (version 1) is a software library developed by the
OpenDNSSEC project
(<a class="link" href="http://www.opendnssec.org" target="_top">
http://www.opendnssec.org
</a>)
which provides a
PKCS#11 interface to a virtual HSM, implemented in the form of
a SQLite3 database on the local filesystem. SoftHSM uses
the Botan library to perform cryptographic functions. Though
less secure than a true HSM, it can allow you to experiment
with PKCS#11 when an HSM is not available.
</p>
<p>
The SoftHSM cryptographic store must be installed and
initialized before using it with OpenSSL, and the SOFTHSM_CONF
environment variable must always point to the SoftHSM configuration
file:
</p>
<pre class="screen">
$ <strong class="userinput"><code> cd softhsm-1.3.7 </code></strong>
$ <strong class="userinput"><code> configure --prefix=/opt/pkcs11/usr </code></strong>
$ <strong class="userinput"><code> make </code></strong>
$ <strong class="userinput"><code> make install </code></strong>
$ <strong class="userinput"><code> export SOFTHSM_CONF=/opt/pkcs11/softhsm.conf </code></strong>
$ <strong class="userinput"><code> echo "0:/opt/pkcs11/softhsm.db" &gt; $SOFTHSM_CONF </code></strong>
$ <strong class="userinput"><code> /opt/pkcs11/usr/bin/softhsm --init-token 0 --slot 0 --label softhsm </code></strong>
</pre>
<p>
SoftHSM can perform all cryptographic operations, but
since it only uses your system CPU, there is no advantage to using
it for anything but signing. Therefore, we choose the 'sign-only'
flavor when building OpenSSL.
</p>
<pre class="screen">
$ <strong class="userinput"><code>cd openssl-0.9.8zc</code></strong>
$ <strong class="userinput"><code>/Configure linux-x86_64 -pthread \
--pk11-libname=/opt/pkcs11/usr/lib/libsofthsm.so \
--pk11-flavor=sign-only \
--prefix=/opt/pkcs11/usr</code></strong>
</pre>
<p>
After configuring, run "<span class="command"><strong>make</strong></span>"
and "<span class="command"><strong>make test</strong></span>".
</p>
</div>
<p>
Once you have built OpenSSL, run
"<span class="command"><strong>apps/openssl engine pkcs11</strong></span>" to confirm
that PKCS#11 support was compiled in correctly. The output
should be one of the following lines, depending on the flavor
selected:
</p>
<pre class="screen">
(pkcs11) PKCS #11 engine support (sign only)
</pre>
<p>Or:</p>
<pre class="screen">
(pkcs11) PKCS #11 engine support (crypto accelerator)
</pre>
<p>
Next, run
"<span class="command"><strong>apps/openssl engine pkcs11 -t</strong></span>". This will
attempt to initialize the PKCS#11 engine. If it is able to
do so successfully, it will report
<span class="quote">&#8220;<span class="quote"><code class="literal">[ available ]</code></span>&#8221;</span>.
</p>
<p>
If the output is correct, run
"<span class="command"><strong>make install</strong></span>" which will install the
modified OpenSSL suite to <code class="filename">/opt/pkcs11/usr</code>.
</p>
<div class="section">
<div class="titlepage"><div><div><h4 class="title">
<a name="id-1.5.12.8.18"></a>Configuring BIND 9 for Linux with the AEP Keyper</h4></div></div></div>
<p>
To link with the PKCS#11 provider, threads must be
enabled in the BIND 9 build.
</p>
<pre class="screen">
$ <strong class="userinput"><code>cd /bind9</code></strong>
$ <strong class="userinput"><code>/configure --enable-threads \
--with-openssl=/opt/pkcs11/usr \
--with-pkcs11=/opt/pkcs11/usr/lib/libpkcs11.so</code></strong>
</pre>
</div>
<div class="section">
<div class="titlepage"><div><div><h4 class="title">
<a name="id-1.5.12.8.19"></a>Configuring BIND 9 for Solaris with the SCA 6000</h4></div></div></div>
<p>
To link with the PKCS#11 provider, threads must be
enabled in the BIND 9 build.
</p>
<pre class="screen">
$ <strong class="userinput"><code>cd /bind9</code></strong>
$ <strong class="userinput"><code>/configure CC="cc -xarch=amd64" --enable-threads \
--with-openssl=/opt/pkcs11/usr \
--with-pkcs11=/usr/lib/64/libpkcs11.so</code></strong>
</pre>
<p>(For a 32-bit build, omit CC="cc -xarch=amd64".)</p>
<p>
If configure complains about OpenSSL not working, you
may have a 32/64-bit architecture mismatch. Or, you may have
incorrectly specified the path to OpenSSL (it should be the
same as the --prefix argument to the OpenSSL
Configure).
</p>
</div>
<div class="section">
<div class="titlepage"><div><div><h4 class="title">
<a name="id-1.5.12.8.20"></a>Configuring BIND 9 for SoftHSM</h4></div></div></div>
<pre class="screen">
$ <strong class="userinput"><code>cd /bind9</code></strong>
$ <strong class="userinput"><code>/configure --enable-threads \
--with-openssl=/opt/pkcs11/usr \
--with-pkcs11=/opt/pkcs11/usr/lib/libsofthsm.so</code></strong>
</pre>
</div>
<p>
After configuring, run
"<span class="command"><strong>make</strong></span>",
"<span class="command"><strong>make test</strong></span>" and
"<span class="command"><strong>make install</strong></span>".
</p>
<p>
(Note: If "make test" fails in the "pkcs11" system test, you may
have forgotten to set the SOFTHSM_CONF environment variable.)
</p>
</div>
<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="id-1.5.12.9"></a>PKCS#11 Tools</h3></div></div></div>
<p>
BIND 9 includes a minimal set of tools to operate the
HSM, including
<span class="command"><strong>pkcs11-keygen</strong></span> to generate a new key pair
within the HSM,
<span class="command"><strong>pkcs11-list</strong></span> to list objects currently
available,
<span class="command"><strong>pkcs11-destroy</strong></span> to remove objects, and
<span class="command"><strong>pkcs11-tokens</strong></span> to list available tokens.
</p>
<p>
In UNIX/Linux builds, these tools are built only if BIND
9 is configured with the --with-pkcs11 option. (Note: If
--with-pkcs11 is set to "yes", rather than to the path of the
PKCS#11 provider, then the tools will be built but the
provider will be left undefined. Use the -m option or the
PKCS11_PROVIDER environment variable to specify the path to the
provider.)
</p>
</div>
<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="id-1.5.12.10"></a>Using the HSM</h3></div></div></div>
<p>
For OpenSSL-based PKCS#11, we must first set up the runtime
environment so the OpenSSL and PKCS#11 libraries can be loaded:
</p>
<pre class="screen">
$ <strong class="userinput"><code>export LD_LIBRARY_PATH=/opt/pkcs11/usr/lib:${LD_LIBRARY_PATH}</code></strong>
</pre>
<p>
This causes <span class="command"><strong>named</strong></span> and other binaries to load
the OpenSSL library from <code class="filename">/opt/pkcs11/usr/lib</code>
rather than from the default location. This step is not necessary
when using native PKCS#11.
</p>
<p>
Some HSMs require other environment variables to be set.
For example, when operating an AEP Keyper, it is necessary to
specify the location of the "machine" file, which stores
information about the Keyper for use by the provider
library. If the machine file is in
<code class="filename">/opt/Keyper/PKCS11Provider/machine</code>,
use:
</p>
<pre class="screen">
$ <strong class="userinput"><code>export KEYPER_LIBRARY_PATH=/opt/Keyper/PKCS11Provider</code></strong>
</pre>
<p>
Such environment variables must be set whenever running
any tool that uses the HSM, including
<span class="command"><strong>pkcs11-keygen</strong></span>,
<span class="command"><strong>pkcs11-list</strong></span>,
<span class="command"><strong>pkcs11-destroy</strong></span>,
<span class="command"><strong>dnssec-keyfromlabel</strong></span>,
<span class="command"><strong>dnssec-signzone</strong></span>,
<span class="command"><strong>dnssec-keygen</strong></span>, and
<span class="command"><strong>named</strong></span>.
</p>
<p>
We can now create and use keys in the HSM. In this case,
we will create a 2048 bit key and give it the label
"sample-ksk":
</p>
<pre class="screen">
$ <strong class="userinput"><code>pkcs11-keygen -b 2048 -l sample-ksk</code></strong>
</pre>
<p>To confirm that the key exists:</p>
<pre class="screen">
$ <strong class="userinput"><code>pkcs11-list</code></strong>
Enter PIN:
object[0]: handle 2147483658 class 3 label[8] 'sample-ksk' id[0]
object[1]: handle 2147483657 class 2 label[8] 'sample-ksk' id[0]
</pre>
<p>
Before using this key to sign a zone, we must create a
pair of BIND 9 key files. The "dnssec-keyfromlabel" utility
does this. In this case, we will be using the HSM key
"sample-ksk" as the key-signing key for "example.net":
</p>
<pre class="screen">
$ <strong class="userinput"><code>dnssec-keyfromlabel -l sample-ksk -f KSK example.net</code></strong>
</pre>
<p>
The resulting K*.key and K*.private files can now be used
to sign the zone. Unlike normal K* files, which contain both
public and private key data, these files will contain only the
public key data, plus an identifier for the private key which
remains stored within the HSM. Signing with the private key takes
place inside the HSM.
</p>
<p>
If you wish to generate a second key in the HSM for use
as a zone-signing key, follow the same procedure above, using a
different keylabel, a smaller key size, and omitting "-f KSK"
from the dnssec-keyfromlabel arguments:
</p>
<p>
(Note: When using OpenSSL-based PKCS#11 the label is an arbitrary
string which identifies the key. With native PKCS#11, the label is
a PKCS#11 URI string which may include other details about the key
and the HSM, including its PIN. See
<a class="xref" href="man.dnssec-keyfromlabel.html" title="dnssec-keyfromlabel"><span class="refentrytitle"><span class="application">dnssec-keyfromlabel</span></span>(8)</a> for details.)
</p>
<pre class="screen">
$ <strong class="userinput"><code>pkcs11-keygen -b 1024 -l sample-zsk</code></strong>
$ <strong class="userinput"><code>dnssec-keyfromlabel -l sample-zsk example.net</code></strong>
</pre>
<p>
Alternatively, you may prefer to generate a conventional
on-disk key, using dnssec-keygen:
</p>
<pre class="screen">
$ <strong class="userinput"><code>dnssec-keygen example.net</code></strong>
</pre>
<p>
This provides less security than an HSM key, but since
HSMs can be slow or cumbersome to use for security reasons, it
may be more efficient to reserve HSM keys for use in the less
frequent key-signing operation. The zone-signing key can be
rolled more frequently, if you wish, to compensate for a
reduction in key security. (Note: When using native PKCS#11,
there is no speed advantage to using on-disk keys, as cryptographic
operations will be done by the HSM regardless.)
</p>
<p>
Now you can sign the zone. (Note: If not using the -S
option to <span class="command"><strong>dnssec-signzone</strong></span>, it will be
necessary to add the contents of both <code class="filename">K*.key</code>
files to the zone master file before signing it.)
</p>
<pre class="screen">
$ <strong class="userinput"><code>dnssec-signzone -S example.net</code></strong>
Enter PIN:
Verifying the zone using the following algorithms:
NSEC3RSASHA1.
Zone signing complete:
Algorithm: NSEC3RSASHA1: ZSKs: 1, KSKs: 1 active, 0 revoked, 0 stand-by
example.net.signed
</pre>
</div>
<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="id-1.5.12.11"></a>Specifying the engine on the command line</h3></div></div></div>
<p>
When using OpenSSL-based PKCS#11, the "engine" to be used by
OpenSSL can be specified in <span class="command"><strong>named</strong></span> and all of
the BIND <span class="command"><strong>dnssec-*</strong></span> tools by using the "-E
&lt;engine&gt;" command line option. If BIND 9 is built with
the --with-pkcs11 option, this option defaults to "pkcs11".
Specifying the engine will generally not be necessary unless
for some reason you wish to use a different OpenSSL
engine.
</p>
<p>
If you wish to disable use of the "pkcs11" engine &#8212;
for troubleshooting purposes, or because the HSM is unavailable
&#8212; set the engine to the empty string. For example:
</p>
<pre class="screen">
$ <strong class="userinput"><code>dnssec-signzone -E '' -S example.net</code></strong>
</pre>
<p>
This causes
<span class="command"><strong>dnssec-signzone</strong></span> to run as if it were compiled
without the --with-pkcs11 option.
</p>
<p>
When built with native PKCS#11 mode, the "engine" option has a
different meaning: it specifies the path to the PKCS#11 provider
library. This may be useful when testing a new provider library.
</p>
</div>
<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="id-1.5.12.12"></a>Running named with automatic zone re-signing</h3></div></div></div>
<p>
If you want <span class="command"><strong>named</strong></span> to dynamically re-sign zones
using HSM keys, and/or to to sign new records inserted via nsupdate,
then <span class="command"><strong>named</strong></span> must have access to the HSM PIN. In OpenSSL-based PKCS#11,
this is accomplished by placing the PIN into the openssl.cnf file
(in the above examples,
<code class="filename">/opt/pkcs11/usr/ssl/openssl.cnf</code>).
</p>
<p>
The location of the openssl.cnf file can be overridden by
setting the OPENSSL_CONF environment variable before running
<span class="command"><strong>named</strong></span>.
</p>
<p>Sample openssl.cnf:</p>
<pre class="programlisting">
openssl_conf = openssl_def
[ openssl_def ]
engines = engine_section
[ engine_section ]
pkcs11 = pkcs11_section
[ pkcs11_section ]
PIN = <em class="replaceable"><code>&lt;PLACE PIN HERE&gt;</code></em>
</pre>
<p>
This will also allow the dnssec-* tools to access the HSM
without PIN entry. (The pkcs11-* tools access the HSM directly,
not via OpenSSL, so a PIN will still be required to use
them.)
</p>
<p>
In native PKCS#11 mode, the PIN can be provided in a file specified
as an attribute of the key's label. For example, if a key had the label
<strong class="userinput"><code>pkcs11:object=local-zsk;pin-source=/etc/hsmpin</code></strong>,
then the PIN would be read from the file
<code class="filename">/etc/hsmpin</code>.
</p>
<div class="warning" style="margin-left: 0.5in; margin-right: 0.5in;">
<h3 class="title">Warning</h3>
<p>
Placing the HSM's PIN in a text file in this manner may reduce the
security advantage of using an HSM. Be sure this is what you want to
do before configuring the system in this way.
</p>
</div>
</div>
</div>
<div class="section">
<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="dlz-info"></a>DLZ (Dynamically Loadable Zones)</h2></div></div></div>
<p>
DLZ (Dynamically Loadable Zones) is an extension to BIND 9 that allows
zone data to be retrieved directly from an external database. There is
no required format or schema. DLZ drivers exist for several different
database backends including PostgreSQL, MySQL, and LDAP and can be
written for any other.
</p>
<p>
Historically, DLZ drivers had to be statically linked with the <span class="command"><strong>named</strong></span>
binary and were turned on via a configure option at compile time (for
example, <strong class="userinput"><code>"configure --with-dlz-ldap"</code></strong>).
Currently, the drivers provided in the BIND 9 tarball in
<code class="filename">contrib/dlz/drivers</code> are still linked this
way.
</p>
<p>
In BIND 9.8 and higher, it is possible to link some DLZ modules
dynamically at runtime, via the DLZ "dlopen" driver, which acts as a
generic wrapper around a shared object implementing the DLZ API. The
"dlopen" driver is linked into <span class="command"><strong>named</strong></span> by default, so configure options
are no longer necessary when using these dynamically linkable drivers,
but are still needed for the older drivers in
<code class="filename">contrib/dlz/drivers</code>.
</p>
<p>
When the DLZ module provides data to <span class="command"><strong>named</strong></span>, it does so in text format.
The response is converted to DNS wire format by <span class="command"><strong>named</strong></span>. This
conversion, and the lack of any internal caching, places significant
limits on the query performance of DLZ modules. Consequently, DLZ is
not recommended for use on high-volume servers. However, it can be
used in a hidden master configuration, with slaves retrieving zone
updates via AXFR. (Note, however, that DLZ has no built-in support for
DNS notify; slaves are not automatically informed of changes to the
zones in the database.)
</p>
<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="id-1.5.13.6"></a>Configuring DLZ</h3></div></div></div>
<p>
A DLZ database is configured with a <span class="command"><strong>dlz</strong></span>
statement in <code class="filename">named.conf</code>:
</p>
<pre class="screen">
dlz example {
database "dlopen driver.so <code class="option">args</code>";
search yes;
};
</pre>
<p>
This specifies a DLZ module to search when answering queries; the
module is implemented in <code class="filename">driver.so</code> and is
loaded at runtime by the dlopen DLZ driver. Multiple
<span class="command"><strong>dlz</strong></span> statements can be specified; when
answering a query, all DLZ modules with <code class="option">search</code>
set to <code class="literal">yes</code> will be queried to find out if
they contain an answer for the query name; the best available
answer will be returned to the client.
</p>
<p>
The <code class="option">search</code> option in the above example can be
omitted, because <code class="literal">yes</code> is the default value.
</p>
<p>
If <code class="option">search</code> is set to <code class="literal">no</code>, then
this DLZ module is <span class="emphasis"><em>not</em></span> searched for the best
match when a query is received. Instead, zones in this DLZ must be
separately specified in a zone statement. This allows you to
configure a zone normally using standard zone option semantics,
but specify a different database back-end for storage of the
zone's data. For example, to implement NXDOMAIN redirection using
a DLZ module for back-end storage of redirection rules:
</p>
<pre class="screen">
dlz other {
database "dlopen driver.so <code class="option">args</code>";
search no;
};
zone "." {
type redirect;
dlz other;
};
</pre>
</div>
<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="id-1.5.13.7"></a>Sample DLZ Driver</h3></div></div></div>
<p>
For guidance in implementation of DLZ modules, the directory
<code class="filename">contrib/dlz/example</code> contains a basic
dynamically-linkable DLZ module--i.e., one which can be
loaded at runtime by the "dlopen" DLZ driver.
The example sets up a single zone, whose name is passed
to the module as an argument in the <span class="command"><strong>dlz</strong></span>
statement:
</p>
<pre class="screen">
dlz other {
database "dlopen driver.so example.nil";
};
</pre>
<p>
In the above example, the module is configured to create a zone
"example.nil", which can answer queries and AXFR requests, and
accept DDNS updates. At runtime, prior to any updates, the zone
contains an SOA, NS, and a single A record at the apex:
</p>
<pre class="screen">
example.nil. 3600 IN SOA example.nil. hostmaster.example.nil. (
123 900 600 86400 3600
)
example.nil. 3600 IN NS example.nil.
example.nil. 1800 IN A 10.53.0.1
</pre>
<p>
The sample driver is capable of retrieving information about the
querying client, and altering its response on the basis of this
information. To demonstrate this feature, the example driver
responds to queries for "source-addr.<code class="option">zonename</code>&gt;/TXT"
with the source address of the query. Note, however, that this
record will *not* be included in AXFR or ANY responses. Normally,
this feature would be used to alter responses in some other fashion,
e.g., by providing different address records for a particular name
depending on the network from which the query arrived.
</p>
<p>
Documentation of the DLZ module API can be found in
<code class="filename">contrib/dlz/example/README</code>. This directory also
contains the header file <code class="filename">dlz_minimal.h</code>, which
defines the API and should be included by any dynamically-linkable
DLZ module.
</p>
</div>
</div>
<div class="section">
<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="dyndb-info"></a>DynDB (Dynamic Database)</h2></div></div></div>
<p>
DynDB is an extension to BIND 9 which, like DLZ
(see <a class="xref" href="Bv9ARM.ch04.html#dlz-info" title="DLZ (Dynamically Loadable Zones)">the section called &#8220;DLZ (Dynamically Loadable Zones)&#8221;</a>), allows zone data to be
retrieved from an external database. Unlike DLZ, a DynDB module
provides a full-featured BIND zone database interface. Where
DLZ translates DNS queries into real-time database lookups,
resulting in relatively poor query performance, and is unable
to handle DNSSEC-signed data due to its limited API, a DynDB
module can pre-load an in-memory database from the external
data source, providing the same performance and functionality
as zones served natively by BIND.
</p>
<p>
A DynDB module supporting LDAP has been created by Red Hat
and is available from
<a class="link" href="https://fedorahosted.org/bind-dyndb-ldap/" target="_top">https://fedorahosted.org/bind-dyndb-ldap/</a>.
</p>
<p>
A sample DynDB module for testing and developer guidance
is included with the BIND source code, in the directory
<code class="filename">bin/tests/system/dyndb/driver</code>.
</p>
<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="id-1.5.14.5"></a>Configuring DynDB</h3></div></div></div>
<p>
A DynDB database is configured with a <span class="command"><strong>dyndb</strong></span>
statement in <code class="filename">named.conf</code>:
</p>
<pre class="screen">
dyndb example "driver.so" {
<em class="replaceable"><code>parameters</code></em>
};
</pre>
<p>
The file <code class="filename">driver.so</code> is a DynDB module which
implements the full DNS database API. Multiple
<span class="command"><strong>dyndb</strong></span> statements can be specified, to load
different drivers or multiple instances of the same driver.
Zones provided by a DynDB module are added to the view's zone
table, and are treated as normal authoritative zones when BIND
is responding to queries. Zone configuration is handled internally
by the DynDB module.
</p>
<p>
The <em class="replaceable"><code>parameters</code></em> are passed as an opaque
string to the DynDB module's initialization routine. Configuration
syntax will differ depending on the driver.
</p>
</div>
<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="id-1.5.14.6"></a>Sample DynDB Module</h3></div></div></div>
<p>
For guidance in implementation of DynDB modules, the directory
<code class="filename">bin/tests/system/dyndb/driver</code>.
contains a basic DynDB module.
The example sets up two zones, whose names are passed
to the module as arguments in the <span class="command"><strong>dyndb</strong></span>
statement:
</p>
<pre class="screen">
dyndb sample "sample.so" { example.nil. arpa. };
</pre>
<p>
In the above example, the module is configured to create a zone
"example.nil", which can answer queries and AXFR requests, and
accept DDNS updates. At runtime, prior to any updates, the zone
contains an SOA, NS, and a single A record at the apex:
</p>
<pre class="screen">
example.nil. 86400 IN SOA example.nil. example.nil. (
0 28800 7200 604800 86400
)
example.nil. 86400 IN NS example.nil.
example.nil. 86400 IN A 127.0.0.1
</pre>
<p>
When the zone is updated dynamically, the DynDB module will determine
whether the updated RR is an address (i.e., type A or AAAA) and if
so, it will automatically update the corresponding PTR record in a
reverse zone. (Updates are not stored permanently; all updates are
lost when the server is restarted.)
</p>
</div>
</div>
<div class="section">
<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="catz-info"></a>Catalog Zones</h2></div></div></div>
<p>
A "catalog zone" is a special DNS zone that contains a list of
other zones to be served, along with their configuration parameters.
Zones listed in a catalog zone are called "member zones".
When a catalog zone is loaded or transferred to a slave server
which supports this functionality, the slave server will create
the member zones automatically. When the catalog zone is updated
(for example, to add or delete member zones, or change
their configuration parameters) those changes are immediately put
into effect. Because the catalog zone is a normal DNS zone, these
configuration changes can be propagated using the standard AXFR/IXFR
zone transfer mechanism.
</p>
<p>
Catalog zones' format and behavior are specified as an internet draft
for interoperability among DNS implementations. As of this release, the
latest revision of the DNS catalog zones draft can be found here:
https://datatracker.ietf.org/doc/draft-muks-dnsop-dns-catalog-zones/
</p>
<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="id-1.5.15.4"></a>Principle of Operation</h3></div></div></div>
<p>
Normally, if a zone is to be served by a slave server, the
<code class="filename">named.conf</code> file on the server must list the
zone, or the zone must be added using <span class="command"><strong>rndc addzone</strong></span>.
In environments with a large number of slave servers and/or where
the zones being served are changing frequently, the overhead involved
in maintaining consistent zone configuration on all the slave
servers can be significant.
</p>
<p>
A catalog zone is a way to ease this administrative burden. It is a
DNS zone that lists member zones that should be served by slave servers.
When a slave server receives an update to the catalog zone, it adds,
removes, or reconfigures member zones based on the data received.
</p>
<p>
To use a catalog zone, it must first be set up as a normal zone on
the master and the on slave servers that will be configured to use
it. It must also be added to a <code class="option">catalog-zones</code> list
in the <code class="option">options</code> or <code class="option">view</code> statement
in <code class="filename">named.conf</code>. (This is comparable to the way
a policy zone is configured as a normal zone and also listed in
a <code class="option">response-policy</code> statement.)
</p>
<p>
To use the catalog zone feature to serve a new member zone:
</p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem"><p>
Set up the the member zone to be served on the master as normal.
This could be done by editing <code class="filename">named.conf</code>,
or by running <span class="command"><strong>rndc addzone</strong></span>.
</p></li>
<li class="listitem"><p>
Add an entry to the catalog zone for the new member zone.
This could be done by editing the catalog zone's master file
and running <span class="command"><strong>rndc reload</strong></span>, or by updating
the zone using <span class="command"><strong>nsupdate</strong></span>.
</p></li>
</ul></div>
<p>
The change to the catalog zone will be propagated from the master to all
slaves using the normal AXFR/IXFR mechanism. When the slave receives the
update to the catalog zone, it will detect the entry for the new member
zone, create an instance of of that zone on the slave server, and point
that instance to the <code class="option">masters</code> specified in the catalog
zone data. The newly created member zone is a normal slave zone, so
BIND will immediately initiate a transfer of zone contents from the
master. Once complete, the slave will start serving the member zone.
</p>
<p>
Removing a member zone from a slave server requires nothing more than
deleting the member zone's entry in the catalog zone. The change to the
catalog cone is propagated to the slave server using the normal AXFR/IXFR
transfer mechanism. The slave server, on processing the update, will
notice that the member zone has been removed. It will stop serving the
zone and remove it from its list of configured zones. (Removing the
member zone from the master server has to be done in the normal way,
by editing the configuration file or running
<span class="command"><strong>rndc delzone</strong></span>.)
</p>
</div>
<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="id-1.5.15.5"></a>Configuring Catalog Zones</h3></div></div></div>
<p>
Catalog zones are configured with a <span class="command"><strong>catalog-zones</strong></span>
statement in the <code class="literal">options</code> or <code class="literal">view</code>
section of <code class="filename">named.conf</code>. For example,
</p>
<pre class="screen">
catalog-zones {
zone "catalog.example"
default-masters { 10.53.0.1; }
in-memory no
zone-directory "catzones"
min-update-interval 10;
};
</pre>
<p>
This statement specifies that the zone
<code class="literal">catalog.example</code> is a catalog zone. This zone must be
properly configured in the same view. In most configurations, it would
be a slave zone.
</p>
<p>
The options following the zone name are not required, and may be
specified in any order:
</p>
<p>
The <code class="option">default-masters</code> option defines the default masters
for member zones listed in a catalog zone. This can be overridden by
options within a catalog zone. If no such options are included, then
member zones will transfer their contents from the servers listed in
this option.
</p>
<p>
The <code class="option">in-memory</code> option, if set to <code class="literal">yes</code>,
causes member zones to be stored only in memory. This is functionally
equivalent to configuring a slave zone without a <code class="option">file</code>.
option. The default is <code class="literal">no</code>; member zones' content
will be stored locally in a file whose name is automatically generated
from the view name, catalog zone name, and member zone name.
</p>
<p>
The <code class="option">zone-directory</code> option causes local copies of
member zones' master files (if <code class="option">in-memory</code> is not set
to <code class="literal">yes</code>) to be stored in the specified directory.
The default is to store zone files in the server's working directory.
A non-absolute pathname in <code class="option">zone-directory</code> is
assumed to be relative to the working directory.
</p>
<p>
The <code class="option">min-update-interval</code> option sets the minimum
interval between processing of updates to catalog zones, in seconds.
If an update to a catalog zone (for example, via IXFR) happens less
than <code class="option">min-update-interval</code> seconds after the most
recent update, then the changes will not be carried out until this
interval has elapsed. The default is <code class="literal">5</code> seconds.
</p>
<p>
Catalog zones are defined on a per-view basis. Configuring a non-empty
<code class="option">catalog-zones</code> statement in a view will automatically
turn on <code class="option">allow-new-zones</code> for that view. (Note: this
means <span class="command"><strong>rndc addzone</strong></span> and <span class="command"><strong>rndc delzone</strong></span>
will also work in any view that supports catalog zones.)
</p>
</div>
<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="id-1.5.15.6"></a>Catalog Zone format</h3></div></div></div>
<p>
A catalog zone is a regular DNS zone; therefore, it has to have a
single <code class="literal">SOA</code> and at least one <code class="literal">NS</code>
record.
</p>
<p>
A record stating the version of the catalog zone format is
also required. If the version number listed is not supported by
the server, then a catalog zone may not be used by that server.
</p>
<pre class="screen">
catalog.example. IN SOA . . 2016022901 900 600 86400 1
catalog.example. IN NS nsexample.
version.catalog.example. IN TXT "1"
</pre>
<p>
Note that this record must have the domain name
version.<em class="replaceable"><code>catalog-zone-name</code></em>. This illustrates
how the meaning of data stored in a catalog zone is indicated by the
the domain name label immediately before the catalog zone domain.
</p>
<p>
Catalog zone options can be set either globally for the whole catalog
zone or for a single member zone. Global options override the settings
in the configuration file and member zone options override global
options.
</p>
<p>
Global options are set at the apex of the catalog zone, e.g.:
</p>
<pre class="screen">
masters.catalog.example. IN AAAA 2001:db8::1
</pre>
<p>BIND currently supports the following options:</p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>A simple <code class="option">masters</code> definition:</p>
<pre class="screen">
masters.catalog.example. IN A 192.0.2.1
</pre>
<p>
This option defines a master server for the member zones - it
can be either an A or AAAA record. If multiple masters are set the
order in which they are used is random.
</p>
</li>
<li class="listitem">
<p>A <code class="option">masters</code> with a TSIG key defined:</p>
<pre class="screen">
label.masters.catalog.example. IN A 192.0.2.2
label.masters.catalog.example. IN TXT "tsig_key_name"
</pre>
<p>
This option defines a master server for the member zone with a TSIG
key set. The TSIG key must be configured in the configuration file.
<code class="option">label</code> can be any valid DNS label.
</p>
</li>
<li class="listitem">
<p><code class="option">allow-query</code> and
<code class="option">allow-transfer</code> ACLs:</p>
<pre class="screen">
allow-query.catalog.example. IN APL 1:10.0.0.1/24
allow-transfer.catalog.example. IN APL !1:10.0.0.1/32 1:10.0.0.0/24
</pre>
<p>
These options are the equivalents of <code class="option">allow-query</code>
and <code class="option">allow-transfer</code> in a zone declaration in the
<code class="filename">named.conf</code> configuration file. The ACL is
processed in order - if there's no match to any rule the default
policy is to deny access. For the syntax of the APL RR see RFC
3123
</p>
</li>
</ul></div>
<p>
A member zone is added by including a <code class="literal">PTR</code>
resource record in the <code class="literal">zones</code> sub-domain of the
catalog zone. The record label is a <code class="literal">SHA-1</code> hash
of the member zone name in wire format. The target of the PTR
record is the member zone name. For example, to add the member
zone <code class="literal">domain.example</code>:
</p>
<pre class="screen">
5960775ba382e7a4e09263fc06e7c00569b6a05c.zones.catalog.example. IN PTR domain.example.
</pre>
<p>
The hash is necessary to identify options for a specific member
zone. The member zone-specific options are defined the same way as
global options, but in the member zone subdomain:
</p>
<pre class="screen">
masters.5960775ba382e7a4e09263fc06e7c00569b6a05c.zones.catalog.example. IN A 192.0.2.2
label.masters.5960775ba382e7a4e09263fc06e7c00569b6a05c.zones.catalog.example. IN AAAA 2001:db8::2
label.masters.5960775ba382e7a4e09263fc06e7c00569b6a05c.zones.catalog.example. IN TXT "tsig_key"
allow-query.5960775ba382e7a4e09263fc06e7c00569b6a05c.zones.catalog.example. IN APL 1:10.0.0.0/24
</pre>
<p>
As would be expected, options defined for a specific zone override
the global options defined in the catalog zone. These in turn override
the global options defined in the <code class="literal">catalog-zones</code>
statement in the configuration file.
</p>
<p>
(Note that none of the global records an option will be inherited if
any records are defined for that option for the specific zone. For
example, if the zone had a <code class="literal">masters</code> record of type
A but not AAAA, then it would <span class="emphasis"><em>not</em></span> inherit the
type AAAA record from the global option.)
</p>
</div>
</div>
<div class="section">
<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="ipv6"></a>IPv6 Support in <acronym class="acronym">BIND</acronym> 9</h2></div></div></div>
<p>
<acronym class="acronym">BIND</acronym> 9 fully supports all currently
defined forms of IPv6 name to address and address to name
lookups. It will also use IPv6 addresses to make queries when
running on an IPv6 capable system.
</p>
<p>
For forward lookups, <acronym class="acronym">BIND</acronym> 9 supports
only AAAA records. RFC 3363 deprecated the use of A6 records,
and client-side support for A6 records was accordingly removed
from <acronym class="acronym">BIND</acronym> 9.
However, authoritative <acronym class="acronym">BIND</acronym> 9 name servers still
load zone files containing A6 records correctly, answer queries
for A6 records, and accept zone transfer for a zone containing A6
records.
</p>
<p>
For IPv6 reverse lookups, <acronym class="acronym">BIND</acronym> 9 supports
the traditional "nibble" format used in the
<span class="emphasis"><em>ip6.arpa</em></span> domain, as well as the older, deprecated
<span class="emphasis"><em>ip6.int</em></span> domain.
Older versions of <acronym class="acronym">BIND</acronym> 9
supported the "binary label" (also known as "bitstring") format,
but support of binary labels has been completely removed per
RFC 3363.
Many applications in <acronym class="acronym">BIND</acronym> 9 do not understand
the binary label format at all any more, and will return an
error if given.
In particular, an authoritative <acronym class="acronym">BIND</acronym> 9
name server will not load a zone file containing binary labels.
</p>
<p>
For an overview of the format and structure of IPv6 addresses,
see <a class="xref" href="Bv9ARM.ch11.html#ipv6addresses" title="IPv6 addresses (AAAA)">the section called &#8220;IPv6 addresses (AAAA)&#8221;</a>.
</p>
<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="id-1.5.16.6"></a>Address Lookups Using AAAA Records</h3></div></div></div>
<p>
The IPv6 AAAA record is a parallel to the IPv4 A record,
and, unlike the deprecated A6 record, specifies the entire
IPv6 address in a single record. For example,
</p>
<pre class="programlisting">
$ORIGIN example.com.
host 3600 IN AAAA 2001:db8::1
</pre>
<p>
Use of IPv4-in-IPv6 mapped addresses is not recommended.
If a host has an IPv4 address, use an A record, not
a AAAA, with <code class="literal">::ffff:192.168.42.1</code> as
the address.
</p>
</div>
<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="id-1.5.16.7"></a>Address to Name Lookups Using Nibble Format</h3></div></div></div>
<p>
When looking up an address in nibble format, the address
components are simply reversed, just as in IPv4, and
<code class="literal">ip6.arpa.</code> is appended to the
resulting name.
For example, the following would provide reverse name lookup for
a host with address
<code class="literal">2001:db8::1</code>.
</p>
<pre class="programlisting">
$ORIGIN 0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa.
1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0 14400 IN PTR (
host.example.com. )
</pre>
</div>
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