110 lines
3.9 KiB
Plaintext
110 lines
3.9 KiB
Plaintext
<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
|
|
"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"
|
|
[<!ENTITY mdash "—">]>
|
|
<!--
|
|
- Copyright (C) 2010 Internet Systems Consortium, Inc. ("ISC")
|
|
-
|
|
- Permission to use, copy, modify, and/or distribute this software for any
|
|
- purpose with or without fee is hereby granted, provided that the above
|
|
- copyright notice and this permission notice appear in all copies.
|
|
-
|
|
- THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
|
|
- REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
|
|
- AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
|
|
- INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
|
|
- LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
|
|
- OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
|
|
- PERFORMANCE OF THIS SOFTWARE.
|
|
-->
|
|
|
|
<!-- $Id: isc-hmac-fixup.docbook,v 1.2 2010-01-07 21:52:11 each Exp $ -->
|
|
<refentry id="man.isc-hmac-fixup">
|
|
<refentryinfo>
|
|
<date>January 5, 2010</date>
|
|
</refentryinfo>
|
|
|
|
<refmeta>
|
|
<refentrytitle><application>isc-hmac-fixup</application></refentrytitle>
|
|
<manvolnum>1</manvolnum>
|
|
<refmiscinfo>BIND9</refmiscinfo>
|
|
</refmeta>
|
|
|
|
<refnamediv>
|
|
<refname><application>isc-hmac-fixup</application></refname>
|
|
<refpurpose>fixes HMAC keys generated by older versions of BIND</refpurpose>
|
|
</refnamediv>
|
|
|
|
<docinfo>
|
|
<copyright>
|
|
<year>2010</year>
|
|
<holder>Internet Systems Consortium, Inc. ("ISC")</holder>
|
|
</copyright>
|
|
</docinfo>
|
|
|
|
<refsynopsisdiv>
|
|
<cmdsynopsis>
|
|
<command>isc-hmac-fixup</command>
|
|
<arg choice="req"><replaceable class="parameter">algorithm</replaceable></arg>
|
|
<arg choice="req"><replaceable class="parameter">secret</replaceable></arg>
|
|
</cmdsynopsis>
|
|
</refsynopsisdiv>
|
|
|
|
<refsect1>
|
|
<title>DESCRIPTION</title>
|
|
<para>
|
|
Versions of BIND 9 up to and including BIND 9.6 had a bug causing
|
|
HMAC-SHA* TSIG keys which were longer than the digest length of the
|
|
hash algorithm (i.e., SHA1 keys longer than 160 bits, SHA256 keys
|
|
longer than 256 bits, etc) to be used incorrectly, generating a
|
|
message authentication code that was incompatible with other DNS
|
|
implementations.
|
|
</para>
|
|
<para>
|
|
This bug has been fixed in BIND 9.7. However, the fix may
|
|
cause incompatibility between older and newer versions of
|
|
BIND, when using long keys. <command>isc-hmac-fixup</command>
|
|
modifies those keys to restore compatibility.
|
|
</para>
|
|
<para>
|
|
To modify a key, run <command>isc-hmac-fixup</command> and
|
|
specify the key's algorithm and secret on the command line. If the
|
|
secret is longer than the digest length of the algorithm (64 bytes
|
|
for SHA1 through SHA256, or 128 bytes for SHA384 and SHA512), then a
|
|
new secret will be generated consisting of a hash digest of the old
|
|
secret. (If the secret did not require conversion, then it will be
|
|
printed without modification.)
|
|
</para>
|
|
</refsect1>
|
|
|
|
<refsect1>
|
|
<title>SECURITY CONSIDERATIONS</title>
|
|
<para>
|
|
Secrets that have been converted by <command>isc-hmac-fixup</command>
|
|
are shortened, but as this is how the HMAC protocol works in
|
|
operation anyway, it does not affect security. RFC 2104 notes,
|
|
"Keys longer than [the digest length] are acceptable but the
|
|
extra length would not significantly increase the function
|
|
strength."
|
|
</para>
|
|
</refsect1>
|
|
|
|
<refsect1>
|
|
<title>SEE ALSO</title>
|
|
<para>
|
|
<citetitle>BIND 9 Administrator Reference Manual</citetitle>,
|
|
<citetitle>RFC 2104</citetitle>.
|
|
</para>
|
|
</refsect1>
|
|
|
|
<refsect1>
|
|
<title>AUTHOR</title>
|
|
<para><corpauthor>Internet Systems Consortium</corpauthor>
|
|
</para>
|
|
</refsect1>
|
|
|
|
</refentry><!--
|
|
- Local variables:
|
|
- mode: sgml
|
|
- End:
|
|
-->
|