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DNSSEC Release Notes

This document summarizes the state of the DNSSEC implementation in
this release of BIND9.


OpenSSL Library Required

To support DNSSEC, BIND 9 must be linked with version 0.9.6e or newer of
the OpenSSL library.  As of BIND 9.2, the library is no longer
included in the distribution - it must be provided by the operating
system or installed separately.

To build BIND 9 with OpenSSL, use "configure --with-openssl".  If
the OpenSSL library is installed in a nonstandard location, you can
specify a path as in "configure --with-openssl=/var".


Key Generation and Signing

The tools for generating DNSSEC keys and signatures are now in the
bin/dnssec directory.  Documentation for these programs can be found
in doc/arm/Bv9ARM.4.html and the man pages.

The random data used in generating DNSSEC keys and signatures comes
from either /dev/random (if the OS supports it) or keyboard input.
Alternatively, a device or file containing entropy/random data can be
specified.


Serving Secure Zones

When acting as an authoritative name server, BIND9 includes KEY, SIG
and NXT records in responses as specified in RFC2535 when the request
has the DO flag set in the query.


Secure Resolution

Basic support for validation of DNSSEC signatures in responses has
been implemented but should still be considered experimental.

When acting as a caching name server, BIND9 is capable of performing
basic DNSSEC validation of positive as well as nonexistence responses.
This functionality is enabled by including a "trusted-keys" clause
in the configuration file, containing the top-level zone key of the
the DNSSEC tree.

Validation of wildcard responses is not currently supported.  In
particular, a "name does not exist" response will validate
successfully even if it does not contain the NXT records to prove the
nonexistence of a matching wildcard.

Proof of insecure status for insecure zones delegated from secure
zones works when the zones are completely insecure.  Privately
secured zones delegated from secure zones will not work in all cases,
such as when the privately secured zone is served by the same server
as an ancestor (but not parent) zone.

Handling of the CD bit in queries is now fully implemented.  Validation
is not attempted for recursive queries if CD is set.


Secure Dynamic Update

Dynamic update of secure zones has been implemented, but may not be
complete.  Affected NXT and SIG records are updated by the server when
an update occurs.  Advanced access control is possible using the
"update-policy" statement in the zone definition.


Secure Zone Transfers

BIND 9 does not implement the zone transfer security mechanisms of
RFC2535 section 5.6, and we have no plans to implement them in the
future as we consider them inferior to the use of TSIG or SIG(0) to
ensure the integrity of zone transfers.