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11e9368a226272085c337e9e74b79808c16fbdbaTinderbox User - Copyright (C) 2004-2009 Internet Systems Consortium, Inc. ("ISC")
75c0816e8295e180f4bc7f10db3d0d880383bc1cMark Andrews - Copyright (C) 2000-2003 Internet Software Consortium.
4a14ce5ba00ab7bc55c99ffdcf59c7a4ab902721Automatic Updater - Permission to use, copy, modify, and distribute this software for any
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein - purpose with or without fee is hereby granted, provided that the above
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein - copyright notice and this permission notice appear in all copies.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein - THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein - REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein - AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein - INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein - LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein - OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein - PERFORMANCE OF THIS SOFTWARE.
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fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User<title>Chapter�4.�Advanced DNS Features</title>
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60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<tr><th colspan="3" align="center">Chapter�4.�Advanced DNS Features</th></tr>
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fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User<div class="titlepage"><div><div><h2 class="title">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<a name="Bv9ARM.ch04"></a>Chapter�4.�Advanced DNS Features</h2></div></div></div>
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt<dt><span class="sect1"><a href="Bv9ARM.ch04.html#notify">Notify</a></span></dt>
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt<dt><span class="sect1"><a href="Bv9ARM.ch04.html#dynamic_update">Dynamic Update</a></span></dt>
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt<dd><dl><dt><span class="sect2"><a href="Bv9ARM.ch04.html#journal">The journal file</a></span></dt></dl></dd>
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User<dt><span class="sect1"><a href="Bv9ARM.ch04.html#incremental_zone_transfers">Incremental Zone Transfers (IXFR)</a></span></dt>
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User<dt><span class="sect1"><a href="Bv9ARM.ch04.html#id2570513">Split DNS</a></span></dt>
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt<dd><dl><dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2570531">Example split DNS setup</a></span></dt></dl></dd>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<dt><span class="sect1"><a href="Bv9ARM.ch04.html#tsig">TSIG</a></span></dt>
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2571169">Generate Shared Keys for Each Pair of Hosts</a></span></dt>
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2571242">Copying the Shared Secret to Both Machines</a></span></dt>
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2571253">Informing the Servers of the Key's Existence</a></span></dt>
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2571292">Instructing the Server to Use the Key</a></span></dt>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2571486">TSIG Key Based Access Control</a></span></dt>
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2571531">Errors</a></span></dt>
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt<dt><span class="sect1"><a href="Bv9ARM.ch04.html#id2571613">TKEY</a></span></dt>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<dt><span class="sect1"><a href="Bv9ARM.ch04.html#id2571662">SIG(0)</a></span></dt>
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User<dt><span class="sect1"><a href="Bv9ARM.ch04.html#DNSSEC">DNSSEC</a></span></dt>
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2571799">Generating Keys</a></span></dt>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2571878">Signing the Zone</a></span></dt>
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2571959">Configuring Servers</a></span></dt>
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User<dt><span class="sect1"><a href="Bv9ARM.ch04.html#id2572102">IPv6 Support in <acronym class="acronym">BIND</acronym> 9</a></span></dt>
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2572164">Address Lookups Using AAAA Records</a></span></dt>
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2572185">Address to Name Lookups Using Nibble Format</a></span></dt>
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User<div class="titlepage"><div><div><h2 class="title" style="clear: both">
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User<a name="notify"></a>Notify</h2></div></div></div>
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User <acronym class="acronym">DNS</acronym> NOTIFY is a mechanism that allows master
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User servers to notify their slave servers of changes to a zone's data. In
6f64d4ab8e68f9b2333bcbfc755396d29a4a9d7cAutomatic Updater response to a <span><strong class="command">NOTIFY</strong></span> from a master server, the
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt slave will check to see that its version of the zone is the
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater current version and, if not, initiate a zone transfer.
bbbf2e27d3a981163dab139497d6b2dc85449db0Tinderbox User For more information about <acronym class="acronym">DNS</acronym>
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt <span><strong class="command">NOTIFY</strong></span>, see the description of the
bbbf2e27d3a981163dab139497d6b2dc85449db0Tinderbox User <span><strong class="command">notify</strong></span> option in <a href="Bv9ARM.ch06.html#boolean_options" title="Boolean Options">the section called “Boolean Options”</a> and
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User the description of the zone option <span><strong class="command">also-notify</strong></span> in
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User <a href="Bv9ARM.ch06.html#zone_transfers" title="Zone Transfers">the section called “Zone Transfers”</a>. The <span><strong class="command">NOTIFY</strong></span>
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User protocol is specified in RFC 1996.
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User As a slave zone can also be a master to other slaves, named,
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater by default, sends <span><strong class="command">NOTIFY</strong></span> messages for every zone
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt it loads. Specifying <span><strong class="command">notify master-only;</strong></span> will
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater cause named to only send <span><strong class="command">NOTIFY</strong></span> for master
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User zones that it loads.
bcf15a19ae0efa72a22cdfb50666a3c6ce39eb9fTinderbox User<div class="titlepage"><div><div><h2 class="title" style="clear: both">
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User<a name="dynamic_update"></a>Dynamic Update</h2></div></div></div>
983df82baf1d7d0b668c98cf45928a19f175c6e7Tinderbox User Dynamic Update is a method for adding, replacing or deleting
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User records in a master server by sending it a special form of DNS
983df82baf1d7d0b668c98cf45928a19f175c6e7Tinderbox User messages. The format and meaning of these messages is specified
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Dynamic update is enabled by including an
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span><strong class="command">allow-update</strong></span> or <span><strong class="command">update-policy</strong></span>
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User clause in the <span><strong class="command">zone</strong></span> statement. The
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span><strong class="command">tkey-gssapi-credential</strong></span> and
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span><strong class="command">tkey-domain</strong></span> clauses in the
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User <span><strong class="command">options</strong></span> statement enable the
71c66a876ecca77923638d3f94cc0783152b2f03Mark Andrews server to negotiate keys that can be matched against those
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein in <span><strong class="command">update-policy</strong></span> or
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt <span><strong class="command">allow-update</strong></span>.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Updating of secure zones (zones using DNSSEC) follows RFC
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User 3007: RRSIG, NSEC and NSEC3 records affected by updates are
71c66a876ecca77923638d3f94cc0783152b2f03Mark Andrews automatically regenerated by the server using an online
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt zone key. Update authorization is based on transaction
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt signatures and an explicit server policy.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="titlepage"><div><div><h3 class="title">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<a name="journal"></a>The journal file</h3></div></div></div>
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews All changes made to a zone using dynamic update are stored
dec590a3deb8e87380a8bd3a77d535dba3729bf6Tinderbox User in the zone's journal file. This file is automatically created
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt by the server when the first dynamic update takes place.
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt The name of the journal file is formed by appending the extension
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt <code class="filename">.jnl</code> to the name of the
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt corresponding zone
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews file unless specifically overridden. The journal file is in a
dec590a3deb8e87380a8bd3a77d535dba3729bf6Tinderbox User binary format and should not be edited manually.
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User The server will also occasionally write ("dump")
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein the complete contents of the updated zone to its zone file.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein This is not done immediately after
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User each dynamic update, because that would be too slow when a large
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein zone is updated frequently. Instead, the dump is delayed by
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein up to 15 minutes, allowing additional updates to take place.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein When a server is restarted after a shutdown or crash, it will replay
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User the journal file to incorporate into the zone any updates that
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt place after the last zone dump.
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User Changes that result from incoming incremental zone transfers are
3cddb2c552ee6582e8db0849c28747f6b6ca57feAutomatic Updater journalled in a similar way.
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt The zone files of dynamic zones cannot normally be edited by
852ccdd42a71550c974111b49415204ffeca6573Automatic Updater hand because they are not guaranteed to contain the most recent
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User dynamic changes — those are only in the journal file.
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater The only way to ensure that the zone file of a dynamic zone
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater is up to date is to run <span><strong class="command">rndc stop</strong></span>.
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt If you have to make changes to a dynamic zone
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater manually, the following procedure will work: Disable dynamic updates
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater to the zone using
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater <span><strong class="command">rndc freeze <em class="replaceable"><code>zone</code></em></strong></span>.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein This will also remove the zone's <code class="filename">.jnl</code> file
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User and update the master file. Edit the zone file. Run
38417cbfb1a328c20b5b723b8584a02c57f88897Automatic Updater <span><strong class="command">rndc thaw <em class="replaceable"><code>zone</code></em></strong></span>
38417cbfb1a328c20b5b723b8584a02c57f88897Automatic Updater to reload the changed zone and re-enable dynamic updates.
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User<div class="titlepage"><div><div><h2 class="title" style="clear: both">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<a name="incremental_zone_transfers"></a>Incremental Zone Transfers (IXFR)</h2></div></div></div>
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User The incremental zone transfer (IXFR) protocol is a way for
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein slave servers to transfer only changed data, instead of having to
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein transfer the entire zone. The IXFR protocol is specified in RFC
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein 1995. See <a href="Bv9ARM.ch09.html#proposed_standards">Proposed Standards</a>.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein When acting as a master, <acronym class="acronym">BIND</acronym> 9
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein supports IXFR for those zones
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein where the necessary change history information is available. These
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein include master zones maintained by dynamic update and slave zones
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User whose data was obtained by IXFR. For manually maintained master
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein zones, and for slave zones obtained by performing a full zone
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein transfer (AXFR), IXFR is supported only if the option
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span><strong class="command">ixfr-from-differences</strong></span> is set
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein to <strong class="userinput"><code>yes</code></strong>.
3a5fe5abf08f16b8d31ab8ee9a788063110ef000Automatic Updater When acting as a slave, <acronym class="acronym">BIND</acronym> 9 will
3a5fe5abf08f16b8d31ab8ee9a788063110ef000Automatic Updater attempt to use IXFR unless
3a5fe5abf08f16b8d31ab8ee9a788063110ef000Automatic Updater it is explicitly disabled. For more information about disabling
3a5fe5abf08f16b8d31ab8ee9a788063110ef000Automatic Updater IXFR, see the description of the <span><strong class="command">request-ixfr</strong></span> clause
3a5fe5abf08f16b8d31ab8ee9a788063110ef000Automatic Updater of the <span><strong class="command">server</strong></span> statement.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="titlepage"><div><div><h2 class="title" style="clear: both">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<a name="id2570513"></a>Split DNS</h2></div></div></div>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Setting up different views, or visibility, of the DNS space to
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User internal and external resolvers is usually referred to as a
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span class="emphasis"><em>Split DNS</em></span> setup. There are several
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein reasons an organization would want to set up its DNS this way.
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User One common reason for setting up a DNS system this way is
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein to hide "internal" DNS information from "external" clients on the
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Internet. There is some debate as to whether or not this is actually
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Internal DNS information leaks out in many ways (via email headers,
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt for example) and most savvy "attackers" can find the information
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein they need using other means.
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User However, since listing addresses of internal servers that
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein external clients cannot possibly reach can result in
794b79e6bbc3f5db1ea6ae154d739b9f1ef1a375Tinderbox User connection delays and other annoyances, an organization may
794b79e6bbc3f5db1ea6ae154d739b9f1ef1a375Tinderbox User choose to use a Split DNS to present a consistent view of itself
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt to the outside world.
794b79e6bbc3f5db1ea6ae154d739b9f1ef1a375Tinderbox User Another common reason for setting up a Split DNS system is
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt to allow internal networks that are behind filters or in RFC 1918
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein space (reserved IP space, as documented in RFC 1918) to resolve DNS
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein on the Internet. Split DNS can also be used to allow mail from outside
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User back in to the internal network.
794b79e6bbc3f5db1ea6ae154d739b9f1ef1a375Tinderbox User<div class="titlepage"><div><div><h3 class="title">
794b79e6bbc3f5db1ea6ae154d739b9f1ef1a375Tinderbox User<a name="id2570531"></a>Example split DNS setup</h3></div></div></div>
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt Let's say a company named <span class="emphasis"><em>Example, Inc.</em></span>
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User has several corporate sites that have an internal network with
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User Internet Protocol (IP) space and an external demilitarized zone (DMZ),
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein or "outside" section of a network, that is available to the public.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span class="emphasis"><em>Example, Inc.</em></span> wants its internal clients
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein to be able to resolve external hostnames and to exchange mail with
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein people on the outside. The company also wants its internal resolvers
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt to have access to certain internal-only zones that are not available
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein at all outside of the internal network.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein In order to accomplish this, the company will set up two sets
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein of name servers. One set will be on the inside network (in the
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein IP space) and the other set will be on bastion hosts, which are
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein hosts that can talk to both sides of its network, in the DMZ.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein The internal servers will be configured to forward all queries,
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User except queries for <code class="filename">site1.internal</code>, <code class="filename">site2.internal</code>, <code class="filename">site1.example.com</code>,
71c66a876ecca77923638d3f94cc0783152b2f03Mark Andrews and <code class="filename">site2.example.com</code>, to the servers
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein DMZ. These internal servers will have complete sets of information
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt for <code class="filename">site1.example.com</code>, <code class="filename">site2.example.com</code>, <code class="filename">site1.internal</code>,
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User To protect the <code class="filename">site1.internal</code> and <code class="filename">site2.internal</code> domains,
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein the internal name servers must be configured to disallow all queries
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User to these domains from any external hosts, including the bastion
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews The external servers, which are on the bastion hosts, will
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews be configured to serve the "public" version of the <code class="filename">site1</code> and <code class="filename">site2.example.com</code> zones.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein This could include things such as the host records for public servers
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User (<code class="filename">www.example.com</code> and <code class="filename">ftp.example.com</code>),
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein and mail exchange (MX) records (<code class="filename">a.mx.example.com</code> and <code class="filename">b.mx.example.com</code>).
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein In addition, the public <code class="filename">site1</code> and <code class="filename">site2.example.com</code> zones
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein should have special MX records that contain wildcard (`*') records
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein pointing to the bastion hosts. This is needed because external mail
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein servers do not have any other way of looking up how to deliver mail
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews to those internal hosts. With the wildcard records, the mail will
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews be delivered to the bastion host, which can then forward it on to
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews internal hosts.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Here's an example of a wildcard MX record:
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<pre class="programlisting">* IN MX 10 external1.example.com.</pre>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Now that they accept mail on behalf of anything in the internal
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein network, the bastion hosts will need to know how to deliver mail
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein to internal hosts. In order for this to work properly, the resolvers
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User the bastion hosts will need to be configured to point to the internal
bea931e17b7567f09107f93ab7e25c7f00abeb9cMark Andrews name servers for DNS resolution.
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User Queries for internal hostnames will be answered by the internal
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User servers, and queries for external hostnames will be forwarded back
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User out to the DNS servers on the bastion hosts.
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User In order for all this to work properly, internal clients will
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User need to be configured to query <span class="emphasis"><em>only</em></span> the internal
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User name servers for DNS queries. This could also be enforced via
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User filtering on the network.
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User If everything has been set properly, <span class="emphasis"><em>Example, Inc.</em></span>'s
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User internal clients will now be able to:
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User Look up any hostnames in the <code class="literal">site1</code>
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User <code class="literal">site2.example.com</code> zones.
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User Look up any hostnames in the <code class="literal">site1.internal</code> and
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User <code class="literal">site2.internal</code> domains.
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User<li>Look up any hostnames on the Internet.</li>
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User<li>Exchange mail with both internal and external people.</li>
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User Hosts on the Internet will be able to:
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User Look up any hostnames in the <code class="literal">site1</code>
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User <code class="literal">site2.example.com</code> zones.
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User Exchange mail with anyone in the <code class="literal">site1</code> and
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User <code class="literal">site2.example.com</code> zones.
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User Here is an example configuration for the setup we just
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User described above. Note that this is only configuration information;
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User for information on how to configure your zone files, see <a href="Bv9ARM.ch03.html#sample_configuration" title="Sample Configurations">the section called “Sample Configurations”</a>.
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User Internal DNS server config:
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox Useracl internals { 172.16.72.0/24; 192.168.1.0/24; };
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox Useracl externals { <code class="varname">bastion-ips-go-here</code>; };
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User forward only;
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User forwarders { // forward to external servers
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User <code class="varname">bastion-ips-go-here</code>;
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User allow-transfer { none; }; // sample allow-transfer (no one)
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User allow-query { internals; externals; }; // restrict query access
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User allow-recursion { internals; }; // restrict recursion
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox Userzone "site1.example.com" { // sample master zone
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User forwarders { }; // do normal iterative
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User // resolution (do not forward)
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User allow-query { internals; externals; };
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User allow-transfer { internals; };
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox Userzone "site2.example.com" { // sample slave zone
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt masters { 172.16.72.3; };
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User forwarders { };
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User allow-query { internals; externals; };
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User allow-transfer { internals; };
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User forwarders { };
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User allow-query { internals; };
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein allow-transfer { internals; }
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User masters { 172.16.72.3; };
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User forwarders { };
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User allow-query { internals };
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User allow-transfer { internals; }
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User External (bastion host) DNS server config:
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox Useracl internals { 172.16.72.0/24; 192.168.1.0/24; };
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox Useracl externals { bastion-ips-go-here; };
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein allow-transfer { none; }; // sample allow-transfer (no one)
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein allow-query { any; }; // default query access
c71787bd6356c92e9c7d0a174cd63ab17fcf34c6Eric Luce allow-query-cache { internals; externals; }; // restrict cache access
c71787bd6356c92e9c7d0a174cd63ab17fcf34c6Eric Luce allow-recursion { internals; externals; }; // restrict recursion
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Lucezone "site1.example.com" { // sample slave zone
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce type master;
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater allow-transfer { internals; externals; };
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater masters { another_bastion_host_maybe; };
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater allow-transfer { internals; externals; }
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce In the <code class="filename">resolv.conf</code> (or equivalent) on
c71787bd6356c92e9c7d0a174cd63ab17fcf34c6Eric Luce the bastion host(s):
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Lucenameserver 172.16.72.2
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updaternameserver 172.16.72.3
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updaternameserver 172.16.72.4
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater<div class="titlepage"><div><div><h2 class="title" style="clear: both">
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater<a name="tsig"></a>TSIG</h2></div></div></div>
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce This is a short guide to setting up Transaction SIGnatures
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce (TSIG) based transaction security in <acronym class="acronym">BIND</acronym>. It describes changes
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce to the configuration file as well as what changes are required for
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce different features, including the process of creating transaction
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce keys and using transaction signatures with <acronym class="acronym">BIND</acronym>.
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce <acronym class="acronym">BIND</acronym> primarily supports TSIG for server
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce to server communication.
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce This includes zone transfer, notify, and recursive query messages.
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce Resolvers based on newer versions of <acronym class="acronym">BIND</acronym> 8 have limited support
c71787bd6356c92e9c7d0a174cd63ab17fcf34c6Eric Luce TSIG can also be useful for dynamic update. A primary
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce server for a dynamic zone should control access to the dynamic
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce update service, but IP-based access control is insufficient.
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce The cryptographic access control provided by TSIG
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce is far superior. The <span><strong class="command">nsupdate</strong></span>
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce program supports TSIG via the <code class="option">-k</code> and
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce <code class="option">-y</code> command line options or inline by use
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce of the <span><strong class="command">key</strong></span>.
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User<div class="titlepage"><div><div><h3 class="title">
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User<a name="id2571169"></a>Generate Shared Keys for Each Pair of Hosts</h3></div></div></div>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein A shared secret is generated to be shared between <span class="emphasis"><em>host1</em></span> and <span class="emphasis"><em>host2</em></span>.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein An arbitrary key name is chosen: "host1-host2.". The key name must
c71787bd6356c92e9c7d0a174cd63ab17fcf34c6Eric Luce be the same on both hosts.
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce<div class="titlepage"><div><div><h4 class="title">
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce<a name="id2571186"></a>Automatic Generation</h4></div></div></div>
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater The following command will generate a 128-bit (16 byte) HMAC-MD5
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater key as described above. Longer keys are better, but shorter keys
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater are easier to read. Note that the maximum key length is 512 bits;
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater keys longer than that will be digested with MD5 to produce a
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater <strong class="userinput"><code>dnssec-keygen -a hmac-md5 -b 128 -n HOST host1-host2.</code></strong>
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce The key is in the file <code class="filename">Khost1-host2.+157+00000.private</code>.
c71787bd6356c92e9c7d0a174cd63ab17fcf34c6Eric Luce Nothing directly uses this file, but the base-64 encoded string
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater following "<code class="literal">Key:</code>"
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater can be extracted from the file and used as a shared secret:
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce<pre class="programlisting">Key: La/E5CjG9O+os1jq0a2jdA==</pre>
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce The string "<code class="literal">La/E5CjG9O+os1jq0a2jdA==</code>" can
c71787bd6356c92e9c7d0a174cd63ab17fcf34c6Eric Luce be used as the shared secret.
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce<div class="titlepage"><div><div><h4 class="title">
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce<a name="id2571224"></a>Manual Generation</h4></div></div></div>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein The shared secret is simply a random sequence of bits, encoded
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User in base-64. Most ASCII strings are valid base-64 strings (assuming
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User the length is a multiple of 4 and only valid characters are used),
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User so the shared secret can be manually generated.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Also, a known string can be run through <span><strong class="command">mmencode</strong></span> or
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce a similar program to generate base-64 encoded data.
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User<div class="titlepage"><div><div><h3 class="title">
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User<a name="id2571242"></a>Copying the Shared Secret to Both Machines</h3></div></div></div>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein This is beyond the scope of DNS. A secure transport mechanism
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User should be used. This could be secure FTP, ssh, telephone, etc.
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User<div class="titlepage"><div><div><h3 class="title">
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User<a name="id2571253"></a>Informing the Servers of the Key's Existence</h3></div></div></div>
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User Imagine <span class="emphasis"><em>host1</em></span> and <span class="emphasis"><em>host 2</em></span>
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User both servers. The following is added to each server's <code class="filename">named.conf</code> file:
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox Userkey host1-host2. {
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User algorithm hmac-md5;
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User The algorithm, hmac-md5, is the only one supported by <acronym class="acronym">BIND</acronym>.
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User The secret is the one generated above. Since this is a secret, it
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User is recommended that either <code class="filename">named.conf</code> be non-world
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User readable, or the key directive be added to a non-world readable
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User file that is included by
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User At this point, the key is recognized. This means that if the
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User server receives a message signed by this key, it can verify the
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User signature. If the signature is successfully verified, the
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User response is signed by the same key.
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User<div class="titlepage"><div><div><h3 class="title">
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User<a name="id2571292"></a>Instructing the Server to Use the Key</h3></div></div></div>
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User Since keys are shared between two hosts only, the server must
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein be told when keys are to be used. The following is added to the <code class="filename">named.conf</code> file
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User for <span class="emphasis"><em>host1</em></span>, if the IP address of <span class="emphasis"><em>host2</em></span> is
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox Userserver 10.1.2.3 {
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User keys { host1-host2. ;};
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Multiple keys may be present, but only the first is used.
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User This directive does not contain any secrets, so it may be in a
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User world-readable
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User If <span class="emphasis"><em>host1</em></span> sends a message that is a request
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User to that address, the message will be signed with the specified key. <span class="emphasis"><em>host1</em></span> will
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User expect any responses to signed messages to be signed with the same
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User A similar statement must be present in <span class="emphasis"><em>host2</em></span>'s
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User configuration file (with <span class="emphasis"><em>host1</em></span>'s address) for <span class="emphasis"><em>host2</em></span> to
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User sign request messages to <span class="emphasis"><em>host1</em></span>.
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User<div class="titlepage"><div><div><h3 class="title">
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User<a name="id2571486"></a>TSIG Key Based Access Control</h3></div></div></div>
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User <acronym class="acronym">BIND</acronym> allows IP addresses and ranges
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User to be specified in ACL
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein definitions and
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User <span><strong class="command">allow-{ query | transfer | update }</strong></span>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein This has been extended to allow TSIG keys also. The above key would
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User be denoted <span><strong class="command">key host1-host2.</strong></span>
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User An example of an allow-update directive would be:
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austeinallow-update { key host1-host2. ;};
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User This allows dynamic updates to succeed only if the request
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User was signed by a key named "<span><strong class="command">host1-host2.</strong></span>".
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User You may want to read about the more powerful
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User <span><strong class="command">update-policy</strong></span> statement in
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User <a href="Bv9ARM.ch06.html#dynamic_update_policies" title="Dynamic Update Policies">the section called “Dynamic Update Policies”</a>.
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User<div class="titlepage"><div><div><h3 class="title">
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User<a name="id2571531"></a>Errors</h3></div></div></div>
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User The processing of TSIG signed messages can result in
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User several errors. If a signed message is sent to a non-TSIG aware
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User server, a FORMERR (format error) will be returned, since the server will not
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User understand the record. This is a result of misconfiguration,
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User since the server must be explicitly configured to send a TSIG
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User signed message to a specific server.
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User If a TSIG aware server receives a message signed by an
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User unknown key, the response will be unsigned with the TSIG
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User extended error code set to BADKEY. If a TSIG aware server
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User receives a message with a signature that does not validate, the
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User response will be unsigned with the TSIG extended error code set
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein to BADSIG. If a TSIG aware server receives a message with a time
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User outside of the allowed range, the response will be signed with
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User the TSIG extended error code set to BADTIME, and the time values
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein will be adjusted so that the response can be successfully
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User verified. In any of these cases, the message's rcode (response code) is set to
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User NOTAUTH (not authenticated).
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User<div class="titlepage"><div><div><h2 class="title" style="clear: both">
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User<a name="id2571613"></a>TKEY</h2></div></div></div>
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User<p><span><strong class="command">TKEY</strong></span>
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User is a mechanism for automatically generating a shared secret
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User between two hosts. There are several "modes" of
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User <span><strong class="command">TKEY</strong></span> that specify how the key is generated
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User or assigned. <acronym class="acronym">BIND</acronym> 9 implements only one of
9d557856c2a19ec95ee73245f60a92f8675cf5baTinderbox User these modes, the Diffie-Hellman key exchange. Both hosts are
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User required to have a Diffie-Hellman KEY record (although this
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User record is not required to be present in a zone). The
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User <span><strong class="command">TKEY</strong></span> process must use signed messages,
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User signed either by TSIG or SIG(0). The result of
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User <span><strong class="command">TKEY</strong></span> is a shared secret that can be used to
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User sign messages with TSIG. <span><strong class="command">TKEY</strong></span> can also be
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User used to delete shared secrets that it had previously
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein The <span><strong class="command">TKEY</strong></span> process is initiated by a
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce or server by sending a signed <span><strong class="command">TKEY</strong></span>
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User (including any appropriate KEYs) to a TKEY-aware server. The
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User server response, if it indicates success, will contain a
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User <span><strong class="command">TKEY</strong></span> record and any appropriate keys.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein this exchange, both participants have enough information to
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User determine the shared secret; the exact process depends on the
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User <span><strong class="command">TKEY</strong></span> mode. When using the
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User Diffie-Hellman
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User <span><strong class="command">TKEY</strong></span> mode, Diffie-Hellman keys are
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein and the shared secret is derived by both participants.
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User<div class="titlepage"><div><div><h2 class="title" style="clear: both">
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User<a name="id2571662"></a>SIG(0)</h2></div></div></div>
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User <acronym class="acronym">BIND</acronym> 9 partially supports DNSSEC SIG(0)
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User transaction signatures as specified in RFC 2535 and RFC2931.
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User uses public/private keys to authenticate messages. Access control
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User is performed in the same manner as TSIG keys; privileges can be
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User granted or denied based on the key name.
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User When a SIG(0) signed message is received, it will only be
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User verified if the key is known and trusted by the server; the server
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein will not attempt to locate and/or validate the key.
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User SIG(0) signing of multiple-message TCP streams is not
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein The only tool shipped with <acronym class="acronym">BIND</acronym> 9 that
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User generates SIG(0) signed messages is <span><strong class="command">nsupdate</strong></span>.
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User<div class="titlepage"><div><div><h2 class="title" style="clear: both">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<a name="DNSSEC"></a>DNSSEC</h2></div></div></div>
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt Cryptographic authentication of DNS information is possible
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt through the DNS Security (<span class="emphasis"><em>DNSSEC-bis</em></span>) extensions,
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein defined in RFC 4033, RFC 4034, and RFC 4035.
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User This section describes the creation and use of DNSSEC signed zones.
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User In order to set up a DNSSEC secure zone, there are a series
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User of steps which must be followed. <acronym class="acronym">BIND</acronym>
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User with several tools
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User that are used in this process, which are explained in more detail
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User below. In all cases, the <code class="option">-h</code> option prints a
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User full list of parameters. Note that the DNSSEC tools require the
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User keyset files to be in the working directory or the
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User directory specified by the <code class="option">-d</code> option, and
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User that the tools shipped with BIND 9.2.x and earlier are not compatible
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User with the current ones.
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User There must also be communication with the administrators of
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User the parent and/or child zone to transmit keys. A zone's security
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User status must be indicated by the parent zone for a DNSSEC capable
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User resolver to trust its data. This is done through the presence
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User or absence of a <code class="literal">DS</code> record at the
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User For other servers to trust data in this zone, they must
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User either be statically configured with this zone's zone key or the
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User zone key of another zone above this one in the DNS tree.
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User<div class="titlepage"><div><div><h3 class="title">
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User<a name="id2571799"></a>Generating Keys</h3></div></div></div>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein The <span><strong class="command">dnssec-keygen</strong></span> program is used to
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User generate keys.
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User A secure zone must contain one or more zone keys. The
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User zone keys will sign all other records in the zone, as well as
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User the zone keys of any secure delegated zones. Zone keys must
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User have the same name as the zone, a name type of
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User <span><strong class="command">ZONE</strong></span>, and must be usable for
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User authentication.
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User It is recommended that zone keys use a cryptographic algorithm
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User designated as "mandatory to implement" by the IETF; currently
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User the only one is RSASHA1.
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User The following command will generate a 768-bit RSASHA1 key for
9d557856c2a19ec95ee73245f60a92f8675cf5baTinderbox User the <code class="filename">child.example</code> zone:
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User <strong class="userinput"><code>dnssec-keygen -a RSASHA1 -b 768 -n ZONE child.example.</code></strong>
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User Two output files will be produced:
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User <code class="filename">Kchild.example.+005+12345.key</code> and
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User <code class="filename">Kchild.example.+005+12345.private</code>
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User 12345 is an example of a key tag). The key filenames contain
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User the key name (<code class="filename">child.example.</code>),
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein algorithm (3
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User is DSA, 1 is RSAMD5, 5 is RSASHA1, etc.), and the key tag (12345 in
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User The private key (in the <code class="filename">.private</code>
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User used to generate signatures, and the public key (in the
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <code class="filename">.key</code> file) is used for signature
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User verification.
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User To generate another key with the same properties (but with
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User a different key tag), repeat the above command.
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User The <span><strong class="command">dnssec-keyfromlabel</strong></span> program is used
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein to get a key pair from a crypto hardware and build the key
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User files. Its usage is similar to <span><strong class="command">dnssec-keygen</strong></span>.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein The public keys should be inserted into the zone file by
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User including the <code class="filename">.key</code> files using
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User <span><strong class="command">$INCLUDE</strong></span> statements.
2b4d1b54f6ca406b8233d9e6fea9593df6dad035Tinderbox User<div class="titlepage"><div><div><h3 class="title">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<a name="id2571878"></a>Signing the Zone</h3></div></div></div>
71c66a876ecca77923638d3f94cc0783152b2f03Mark Andrews The <span><strong class="command">dnssec-signzone</strong></span> program is used
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt to sign a zone.
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User Any <code class="filename">keyset</code> files corresponding to
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein secure subzones should be present. The zone signer will
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein generate <code class="literal">NSEC</code>, <code class="literal">NSEC3</code>
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User and <code class="literal">RRSIG</code> records for the zone, as
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein well as <code class="literal">DS</code> for the child zones if
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <code class="literal">'-g'</code> is specified. If <code class="literal">'-g'</code>
bea931e17b7567f09107f93ab7e25c7f00abeb9cMark Andrews is not specified, then DS RRsets for the secure child
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews zones need to be added manually.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein The following command signs the zone, assuming it is in a
71c66a876ecca77923638d3f94cc0783152b2f03Mark Andrews file called <code class="filename">zone.child.example</code>. By
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein default, all zone keys which have an available private key are
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein used to generate signatures.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <strong class="userinput"><code>dnssec-signzone -o child.example zone.child.example</code></strong>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein One output file is produced:
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <code class="filename">zone.child.example.signed</code>. This
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User should be referenced by <code class="filename">named.conf</code>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein input file for the zone.
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews<p><span><strong class="command">dnssec-signzone</strong></span>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein will also produce a keyset and dsset files and optionally a
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein dlvset file. These are used to provide the parent zone
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein administrators with the <code class="literal">DNSKEYs</code> (or their
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein corresponding <code class="literal">DS</code> records) that are the
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User secure entry point to the zone.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="titlepage"><div><div><h3 class="title">
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User<a name="id2571959"></a>Configuring Servers</h3></div></div></div>
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User To enable <span><strong class="command">named</strong></span> to respond appropriately
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User to DNS requests from DNSSEC aware clients,
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt <span><strong class="command">dnssec-enable</strong></span> must be set to yes.
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User To enable <span><strong class="command">named</strong></span> to validate answers from
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein other servers both <span><strong class="command">dnssec-enable</strong></span> and
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span><strong class="command">dnssec-validation</strong></span> must be set and some
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span><strong class="command">trusted-keys</strong></span> must be configured
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span><strong class="command">trusted-keys</strong></span> are copies of DNSKEY RRs
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein for zones that are used to form the first link in the
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein cryptographic chain of trust. All keys listed in
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span><strong class="command">trusted-keys</strong></span> (and corresponding zones)
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User are deemed to exist and only the listed keys will be used
b05bdb520d83f7ecaad708fe305268c3420be01dMark Andrews to validated the DNSKEY RRset that they are from.
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User <span><strong class="command">trusted-keys</strong></span> are described in more detail
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein later in this document.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Unlike <acronym class="acronym">BIND</acronym> 8, <acronym class="acronym">BIND</acronym>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein 9 does not verify signatures on load, so zone keys for
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein authoritative zones do not need to be specified in the
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein configuration file.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein After DNSSEC gets established, a typical DNSSEC configuration
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein will look something like the following. It has a one or
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein more public keys for the root. This allows answers from
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein outside the organization to be validated. It will also
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein have several keys for parts of the namespace the organization
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein controls. These are here to ensure that named is immune
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein to compromises in the DNSSEC components of the security
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein of parent zones.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austeintrusted-keys {
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein /* Root Key */
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User"." 257 3 3 "BNY4wrWM1nCfJ+CXd0rVXyYmobt7sEEfK3clRbGaTwSJxrGkxJWoZu6I7PzJu/
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt E9gx4UC1zGAHlXKdE4zYIpRhaBKnvcC2U9mZhkdUpd1Vso/HAdjNe8LmMlnzY3
28b3569d6248168e6c00caab951521cc8141a49dAutomatic Updater zy2Xy4klWOADTPzSv9eamj8V18PHGjBLaVtYvk/ln5ZApjYghf+6fElrmLkdaz
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt MQ2OCnACR817DF4BBa7UR/beDHyp5iWTXWSi6XmoJLbG9Scqc7l70KDqlvXR3M
28b3569d6248168e6c00caab951521cc8141a49dAutomatic Updater /lUUVRbkeg1IPJSidmK3ZyCllh4XSKbje/45SKucHgnwU5jefMtq66gKodQj+M
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User iA21AfUVe7u99WzTLzY3qlxDhxYQQ20FQ97S+LKUTpQcq27R7AT3/V5hRQxScI
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Nqwcz4jYqZD2fQdgxbcDTClU0CRBdiieyLMNzXG3";
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt/* Key for our organization's forward zone */
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austeinexample.com. 257 3 5 "AwEAAaxPMcR2x0HbQV4WeZB6oEDX+r0QM65KbhTjrW1ZaARmPhEZZe
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User 3Y9ifgEuq7vZ/zGZUdEGNWy+JZzus0lUptwgjGwhUS1558Hb4JKUbb
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User OTcM8pwXlj0EiX3oDFVmjHO444gLkBO UKUf/mC7HvfwYH/Be22GnC
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein lrinKJp1Og4ywzO9WglMk7jbfW33gUKvirTHr25GL7STQUzBb5Usxt
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User 8lgnyTUHs1t3JwCY5hKZ6CqFxmAVZP20igTixin/1LcrgX/KMEGd/b
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User iuvF4qJCyduieHukuY3H4XMAcR+xia2 nIUPvm/oyWR8BW/hWdzOvn
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein/* Key for our reverse zone. */
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User2.0.192.IN-ADDRPA.NET. 257 3 5 "AQOnS4xn/IgOUpBPJ3bogzwcxOdNax071L18QqZnQQQA
38417cbfb1a328c20b5b723b8584a02c57f88897Automatic Updater VVr+iLhGTnNGp3HoWQLUIzKrJVZ3zggy3WwNT6kZo6c0
38417cbfb1a328c20b5b723b8584a02c57f88897Automatic Updater tszYqbtvchmgQC8CzKojM/W16i6MG/ea fGU3siaOdS0
38417cbfb1a328c20b5b723b8584a02c57f88897Automatic Updater yOI6BgPsw+YZdzlYMaIJGf4M4dyoKIhzdZyQ2bYQrjyQ
38417cbfb1a328c20b5b723b8584a02c57f88897Automatic Updater 4LB0lC7aOnsMyYKHHYeRv PxjIQXmdqgOJGq+vsevG06
38417cbfb1a328c20b5b723b8584a02c57f88897Automatic Updater zW+1xgYJh9rCIfnm1GX/KMgxLPG2vXTD/RnLX+D3T3UL
38417cbfb1a328c20b5b723b8584a02c57f88897Automatic Updater 7HJYHJhAZD5L59VvjSPsZJHeDCUyWYrvPZesZDIRvhDD
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein dnssec-enable yes;
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein dnssec-validation yes;
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein None of the keys listed in this example are valid. In particular,
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User the root key is not valid.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="titlepage"><div><div><h2 class="title" style="clear: both">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<a name="id2572102"></a>IPv6 Support in <acronym class="acronym">BIND</acronym> 9</h2></div></div></div>
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User <acronym class="acronym">BIND</acronym> 9 fully supports all currently
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews defined forms of IPv6
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein name to address and address to name lookups. It will also use
a1b05dea35aa30b152a47115e18bbe679d3fcf19Mark Andrews IPv6 addresses to make queries when running on an IPv6 capable
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User For forward lookups, <acronym class="acronym">BIND</acronym> 9 supports
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User only AAAA records. RFC 3363 deprecated the use of A6 records,
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein and client-side support for A6 records was accordingly removed
af40ebed6257e4ac1996144530b3de317cf4da11Tinderbox User from <acronym class="acronym">BIND</acronym> 9.
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User However, authoritative <acronym class="acronym">BIND</acronym> 9 name servers still
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt load zone files containing A6 records correctly, answer queries
b05bdb520d83f7ecaad708fe305268c3420be01dMark Andrews for A6 records, and accept zone transfer for a zone containing A6
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User For IPv6 reverse lookups, <acronym class="acronym">BIND</acronym> 9 supports
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt the traditional "nibble" format used in the
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt <span class="emphasis"><em>ip6.arpa</em></span> domain, as well as the older, deprecated
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater <span class="emphasis"><em>ip6.int</em></span> domain.
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt Older versions of <acronym class="acronym">BIND</acronym> 9
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater supported the "binary label" (also known as "bitstring") format,
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater but support of binary labels has been completely removed per
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt Many applications in <acronym class="acronym">BIND</acronym> 9 do not understand
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater the binary label format at all any more, and will return an
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater error if given.
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater In particular, an authoritative <acronym class="acronym">BIND</acronym> 9
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater name server will not load a zone file containing binary labels.
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater For an overview of the format and structure of IPv6 addresses,
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater see <a href="Bv9ARM.ch09.html#ipv6addresses" title="IPv6 addresses (AAAA)">the section called “IPv6 addresses (AAAA)”</a>.
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User<div class="titlepage"><div><div><h3 class="title">
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt<a name="id2572164"></a>Address Lookups Using AAAA Records</h3></div></div></div>
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews The IPv6 AAAA record is a parallel to the IPv4 A record,
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt and, unlike the deprecated A6 record, specifies the entire
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews IPv6 address in a single record. For example,
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunthost 3600 IN AAAA 2001:db8::1
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater Use of IPv4-in-IPv6 mapped addresses is not recommended.
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User If a host has an IPv4 address, use an A record, not
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt a AAAA, with <code class="literal">::ffff:192.168.42.1</code> as
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt the address.
71c66a876ecca77923638d3f94cc0783152b2f03Mark Andrews<div class="titlepage"><div><div><h3 class="title">
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews<a name="id2572185"></a>Address to Name Lookups Using Nibble Format</h3></div></div></div>
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews When looking up an address in nibble format, the address
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews components are simply reversed, just as in IPv4, and
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User <code class="literal">ip6.arpa.</code> is appended to the
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews resulting name.
d3907d27cc138f45772d3d63082ae02c7659148aAutomatic Updater For example, the following would provide reverse name lookup for
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews a host with address
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater$ORIGIN 0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa.
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0 14400 IN PTR host.example.com.
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6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews<td width="40%" align="left" valign="top">Chapter�3.�Name Server Configuration�</td>
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