[28280] in Kerberos
Re: Standard mechanisms to manage domain->realm mappings
daemon@ATHENA.MIT.EDU (Jeffrey Altman)
Thu Aug 16 13:04:56 2007
Message-ID: <46C4840E.6070901@secure-endpoints.com>
Date: Thu, 16 Aug 2007 13:06:22 -0400
From: Jeffrey Altman <jaltman@secure-endpoints.com>
MIME-Version: 1.0
To: edward_newman@ml.com
In-Reply-To: <E5F741E838FC2043A0B843E481818138051ADF1A@MLNYC730MB.amrs.win.ml.com>
X-Envelope-From: jaltman@secure-endpoints.com
X-MDaemon-Deliver-To: kerberos@mit.edu
Cc: kerberos@mit.edu
Reply-To: jaltman@secure-endpoints.com
Content-Type: multipart/mixed; boundary="===============2032451233=="
Errors-To: kerberos-bounces@mit.edu
This is a cryptographically signed message in MIME format.
--===============2032451233==
Content-Type: multipart/signed; protocol="application/x-pkcs7-signature";
micalg=sha1; boundary="------------ms020504000306070502040002"
This is a cryptographically signed message in MIME format.
--------------ms020504000306070502040002
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit
Newman, Edward (GTI) wrote:
> The issue here is that the client doesn't know the correct realm for the
> service ticket it only knows the machine FQDN. It would therefore need
> to go the KDC of the realm it belongs to and ask for a service ticket
> for the service FQDN and the client realm.
That is exactly what the referral mechanism is for. The client doesn't
know the realm because
it has no locally configured data from which to make the decision so it
asks its local realm's
KDC to determine the realm based upon the data that it has available to it.
> The KDC, which may support
> trusts to multiple other realms,
If the KDC does not share keys with other realms it cannot perform a
referral as the client
would not be able to authenticate to the referred realm.
> needs some way to map FQDN and/or
> service principal to a specific realm and return this back to the
> client.
This is done by configuring data on the KDC using either the
[domain_realms] section
of the krb5.conf file, lookups in a local or external database, etc.
> Sounds almost like there is a need for another administrative
> protocol to allow trusting realms to share/cache their service
> principals so that the referral directs to the correct trusted realm.
Active Directory and its GC support LDAP for queries. Any KDC that
shares keys with
a Windows Domain can perform lookups against AD to determine if the service
principal name that is requested is present.
I believe it is also possible for organizations that wish to license the
Microsoft propriety
data synchronization protocols to do so.
I'm not sure that it is necessary for there to be yet another database
exchange protocol
defined for sharing inter-realm data. From a practical perspective, the
MIT database
replication protocol, kprop, doesn't even support multi-master yet let
alone something
else. The beauty of the pluggable database back-end support in MIT
Kerberos is that
the OEMs that create enterprise solutions can take the MIT code and
integrate it with
a database back-end that does support multi-master synchronization of
local realm or
global realm data or even performs queries to remote databases on the fly.
Anyone can implement LDAP in front of their directory service /
database. Microsoft,
Novell, etc. have all done it. So there does in fact exist a protocol
for queries and there
are a number of LDAP Content Synchronization products out there.
Where there can
be benefit from standardization is of the "schema" of the data that is
stored and used
to resolve these "where is xxxx located?" queries.
> This would be unnecessary when the KDC shares a common repository (as is
> the case with AD and a GC) but not with cross-forest trusts.
>
There is certainly a mechanism that Microsoft uses for synchronizing
data Global Catalog
data between multiple AD forests.
I'm not sure that the IETF needs to develop one that is specific to the
Kerberos protocol.
The question of zero configuration of clients has been around for a very
long time. We
absolutely need to solve it for Kerberos to become a universal
solution. I am assuming it will
be one of the highest priorities for the Consortium and it will require
the participation of
all of the major implementations.
Jeffrey Altman
Secure Endpoints Inc.
--------------ms020504000306070502040002
Content-Type: application/x-pkcs7-signature; name="smime.p7s"
Content-Transfer-Encoding: base64
Content-Disposition: attachment; filename="smime.p7s"
Content-Description: S/MIME Cryptographic Signature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--------------ms020504000306070502040002--
--===============2032451233==
Content-Type: text/plain; charset="us-ascii"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Content-Disposition: inline
________________________________________________
Kerberos mailing list Kerberos@mit.edu
https://mailman.mit.edu/mailman/listinfo/kerberos
--===============2032451233==--
