man.isc-hmac-fixup.html revision 335c82aebd0da12b401cfac28bd305da95a4d052
b341a780162d809b187a8f35a10bba7642b69798vboxsync - Copyright (C) 2004-2015 Internet Systems Consortium, Inc. ("ISC")
c7769c4b7e84511fcc4a12a85a04dd7fbfd82b46vboxsync - Copyright (C) 2000-2003 Internet Software Consortium.
b341a780162d809b187a8f35a10bba7642b69798vboxsync - Permission to use, copy, modify, and/or distribute this software for any
b341a780162d809b187a8f35a10bba7642b69798vboxsync - purpose with or without fee is hereby granted, provided that the above
069b9101fbd3b049610c5511b1cc9534d01ea472vboxsync - copyright notice and this permission notice appear in all copies.
b341a780162d809b187a8f35a10bba7642b69798vboxsync - THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
b341a780162d809b187a8f35a10bba7642b69798vboxsync - REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
b341a780162d809b187a8f35a10bba7642b69798vboxsync - AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
b341a780162d809b187a8f35a10bba7642b69798vboxsync - INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
b341a780162d809b187a8f35a10bba7642b69798vboxsync - LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
b341a780162d809b187a8f35a10bba7642b69798vboxsync - OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
b341a780162d809b187a8f35a10bba7642b69798vboxsync - PERFORMANCE OF THIS SOFTWARE.
b341a780162d809b187a8f35a10bba7642b69798vboxsync<!-- $Id$ -->
8bf8c6b1914c9e7e60b1547888400668f1774497vboxsync<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
8bf8c6b1914c9e7e60b1547888400668f1774497vboxsync<meta name="generator" content="DocBook XSL Stylesheets V1.71.1">
8bf8c6b1914c9e7e60b1547888400668f1774497vboxsync<link rel="start" href="Bv9ARM.html" title="BIND 9 Administrator Reference Manual">
8bf8c6b1914c9e7e60b1547888400668f1774497vboxsync<link rel="up" href="Bv9ARM.ch13.html" title="Manual pages">
25e7809933827c62bbc0ed7eaff7e43b2d604083vboxsync<link rel="prev" href="man.genrandom.html" title="genrandom">
0455d2f3a3edaae76f0e5f88e07e9b91bdd7f0f7vboxsync<link rel="next" href="man.nsec3hash.html" title="nsec3hash">
0455d2f3a3edaae76f0e5f88e07e9b91bdd7f0f7vboxsync<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF">
5ad4f48b2792391dd4a1aea599953037dfc8f456vboxsync<tr><th colspan="3" align="center"><span class="application">isc-hmac-fixup</span></th></tr>
dca2831bb7bb894093fa34f4c5962f419e0a03cavboxsync<a accesskey="p" href="man.genrandom.html">Prev</a>�</td>
dca2831bb7bb894093fa34f4c5962f419e0a03cavboxsync<td width="20%" align="right">�<a accesskey="n" href="man.nsec3hash.html">Next</a>
5ad4f48b2792391dd4a1aea599953037dfc8f456vboxsync<a name="man.isc-hmac-fixup"></a><div class="titlepage"></div>
5ad4f48b2792391dd4a1aea599953037dfc8f456vboxsync<p><span class="application">isc-hmac-fixup</span> — fixes HMAC keys generated by older versions of BIND</p>
c58a0c1fbc7df7eb18e7dfb7a14b7272ac0e2735vboxsync<div class="cmdsynopsis"><p><code class="command">isc-hmac-fixup</code> {<em class="replaceable"><code>algorithm</code></em>} {<em class="replaceable"><code>secret</code></em>}</p></div>
205712f260faf219ed24c44b8c56c8d8928ac196vboxsync Versions of BIND 9 up to and including BIND 9.6 had a bug causing
0f730ab371ac7844978aa70d4c5eaf209a8fa515vboxsync HMAC-SHA* TSIG keys which were longer than the digest length of the
9f4ab406d222cd081a1522169822c3e7c2d6a718vboxsync hash algorithm (i.e., SHA1 keys longer than 160 bits, SHA256 keys
d3ad4e45b3213d997bac4a8607ef4fbb4384d30bvboxsync longer than 256 bits, etc) to be used incorrectly, generating a
f7422473f089cb7f3b8be1c3fc223c441627d15cvboxsync message authentication code that was incompatible with other DNS
f7422473f089cb7f3b8be1c3fc223c441627d15cvboxsync implementations.
d1e0bb6198393c6a797ba3ab4363c55ca5a76988vboxsync This bug has been fixed in BIND 9.7. However, the fix may
8bf8c6b1914c9e7e60b1547888400668f1774497vboxsync cause incompatibility between older and newer versions of
8bf8c6b1914c9e7e60b1547888400668f1774497vboxsync BIND, when using long keys. <span><strong class="command">isc-hmac-fixup</strong></span>
8bf8c6b1914c9e7e60b1547888400668f1774497vboxsync modifies those keys to restore compatibility.
8bf8c6b1914c9e7e60b1547888400668f1774497vboxsync To modify a key, run <span><strong class="command">isc-hmac-fixup</strong></span> and
8bf8c6b1914c9e7e60b1547888400668f1774497vboxsync specify the key's algorithm and secret on the command line. If the
8bf8c6b1914c9e7e60b1547888400668f1774497vboxsync secret is longer than the digest length of the algorithm (64 bytes
8bf8c6b1914c9e7e60b1547888400668f1774497vboxsync for SHA1 through SHA256, or 128 bytes for SHA384 and SHA512), then a
8bf8c6b1914c9e7e60b1547888400668f1774497vboxsync new secret will be generated consisting of a hash digest of the old
3a8a18c52fd339275dcd738e571005ab6f7432acvboxsync secret. (If the secret did not require conversion, then it will be
90efebbf85da378072fc9050d223d5489960603fvboxsync printed without modification.)
69846319f8d7c0139496e3ebb5a44e8863ff534dvboxsync<a name="id2671029"></a><h2>SECURITY CONSIDERATIONS</h2>
b341a780162d809b187a8f35a10bba7642b69798vboxsync Secrets that have been converted by <span><strong class="command">isc-hmac-fixup</strong></span>
8bf8c6b1914c9e7e60b1547888400668f1774497vboxsync are shortened, but as this is how the HMAC protocol works in
8bf8c6b1914c9e7e60b1547888400668f1774497vboxsync operation anyway, it does not affect security. RFC 2104 notes,
b341a780162d809b187a8f35a10bba7642b69798vboxsync "Keys longer than [the digest length] are acceptable but the
b341a780162d809b187a8f35a10bba7642b69798vboxsync extra length would not significantly increase the function
f1fc3c08d4fe06dea243bcbe27ca164b38af691avboxsync <em class="citetitle">BIND 9 Administrator Reference Manual</em>,
f7422473f089cb7f3b8be1c3fc223c441627d15cvboxsync<p><span class="corpauthor">Internet Systems Consortium</span>
085bc29163eb87e345acaae02789e4c233d51f3bvboxsync<a accesskey="p" href="man.genrandom.html">Prev</a>�</td>
085bc29163eb87e345acaae02789e4c233d51f3bvboxsync<td width="20%" align="center"><a accesskey="u" href="Bv9ARM.ch13.html">Up</a></td>
0de1998ac52682bb5322df476e45f237265ea9b7vboxsync<td width="40%" align="right">�<a accesskey="n" href="man.nsec3hash.html">Next</a>
b341a780162d809b187a8f35a10bba7642b69798vboxsync<td width="20%" align="center"><a accesskey="h" href="Bv9ARM.html">Home</a></td>
90efebbf85da378072fc9050d223d5489960603fvboxsync<td width="40%" align="right" valign="top">�<span class="application">nsec3hash</span>
90efebbf85da378072fc9050d223d5489960603fvboxsync<p style="text-align: center;">BIND 9.11.0pre-alpha</p>