Subject: KRB-WG IETF-55 meeting minutes

From: "Douglas E. Engert" <[email-masked]>
Date: Tue, 26 Nov 2002 09:48:11 -0600

The Kerberos  WG (krb-wg)  meet at 55th IETF, 11/19/02

[13:00] Doug Engert opened the meeting with a review of the agenda. There
where about 60 people attending.

Larry Greenfield <[email-masked]> volunteered to take note. 

[13:10] Cliff Neuman, Kerberos Clarifications

Today is the last day of the WG last call for Kerberos clarifications,
draft-ietf-krb-wg-kerberos-clarifications-02.txt. There were many
comments; http://www.kerberos.isi.edu/people/bcn/krb-revisions/ have
the latest issues and the editor's classification of them.

Sam Hartman is bringing up concerns about authorization data SHOULD 
versus MUSTs. There is consensus that "all authorization data" MUST be 
rejected if not understood and encapsulating elements must be 
be implemented." 

It's decided that there has to be another WG last call once
a new draft reflecting issues has been issued.

[13:18] Ken Raeburn, Encryption and Checksum Specifications for Kerberos 5
draft-ietf-krb-wg-crypto-02.txt
draft-raeburn-krb-rijndael-krb-02.txt

Ken and others believe that clarifications, encryption, and the AES documents
will all have to move simultaneously.

There needs to be another encryption draft because of DES
specification problems. The latest version of the AES document dropped
twofish and 192-bit AES.

One issue is whether there needs to be a new function in the crypto
profile for generating random data to feed into algorithms for
combining keys.

[13:25] Matt Hur, PKINIT
draft-ietf-cat-kerberos-pk-init-16.txt

There have been very few changes in the past few revisions. The goal
is to last call this document shortly after clarifications.

Tom Yu brings up that RFC 2253 transformation from cert to principal
isn't unique. Kurt Zelinga, Tom Yu, Leif Johansson, Bob Morgan, Larry
Greenfield, Jeff Altman, participate in a discussion. General
consensus that the certificate to principal mapping is a site policy
issue but some guidance might be helpful. There was some amount of
confusion when PKTAPP was brought up, since then services (and not
just KDCs) will be making the mapping.

Agreement to discuss the mapping problem on the list and there will be
another version of the draft.

[13:46] Sam Hartman, Kerberos set/change password
draft-ietf-cat-kerberos-set-passwd-06.txt

Issue #1: This specification implicitly changes the Kerberos protocol
by making restrictions on what addresses are passed to krb_mk_priv().

Issue #2: The draft currently specifies UTF-8; it would be nice to
have something that works now and continues to work after extensions
makes Kerberos Unicode friendly. This brings up non-unicode
characters, stringprep, and where to normalize.

Sam recommends sending unnormalized UTF-8 to the server with a
recommendation to confine to US-ASCII if you want to interoperate now.

Issue #3: Sam would like to force some principals to only have random
keys. There's a concern from the crowd that the KDC is currently a
free source of entropy. Leif thinks that a fix to this draft may
help sync ldap change password extend operations with set-change password. 
There was also discussions about aligning krb password policy
with ldap password policy schema as part of the schema work...

The chair sees consensus that set/change password should be withdrawn
from the IESG, fixed, and resubmitted.

[14:00] End of first session, 15 minute break.

[14:15] Cliff Neuman, Kerberos Extensions
<no current draft>

Cliff summarizes where extensions came from and what the goals
are. Jeff Altman contributes that the i18n extensions mostly revolve
around normalization. Many of the things listed for extensions (client
canonicalization, updating MUSTs versus SHOULDs) have actually been
done or partially done in clarifications.

Tom Yu brings up the edata outstanding issues, including authenticated
cleartext and typed data inside of edata. Sam Hartman relays that
previous consensus in Feb was that the typed data wasn't the general
solution. Sam also brings up problems with name space constraints that
are mentioned in clarifications and should be addressed in extensions
(cross-realm cache poisoning).

Cliff talks about what will be enabled by extensions and emphasized
backwards compatibility. Matt Hur queries if this will still be
Kerberos v5 or if the protocol number should change. An impassioned
discussion follows where many people say "who cares what the protocol
number is".

[14:42] Glen Zorn, IAKERB
draft-ietf-cat-iakerb-08.txt

Glen talks about the current state of the draft (in the hands of the
IESG) and, upon querying by the chair, says that he's not familiar
with Martin Rex's objections. Glen thought Symbol might have done an
implementation of IAKERB, but the crowd disagrees.

Jeff Hutzelman relays some of Martin Rex's concerns, like "SPNEGO in
this protocol has no value" and "under specified for a GSS mechanism"
so "no two implementations will interoperate". The document editor,
Jonathan Trostle, thought that he had addressed Martin's comments.

The chair notes that the WG is still waiting on Jeff Schiller's comments.

There is consensus that IAKERB is seriously flawed if it can't deal
with multiple round trips and various preauth mechanisms. Glen Zorn
dissents.

The WG discusses moving the document to experimental instead of
standards-track. The chair asks if the WG should withdraw this
document; the room is split 50-50 with no consensus. The chair notes
that those in favor for withdrawal, are mostly core developers, those
in favor of not withdrawal are vendors who might still find it useful.

[14:50] Derek Atkins, Krb5-EAP

Derek presents an alternative to IAKERB and believes he will have a
draft out in mid-December. His approach uses EAP to tunnel "random"
Kerberos messages.

[14:55] Ken Hornstein, initial authentication
draft-ietf-krb-wg-hw-auth-02.txt
draft-ietf-krb-wg-kerberos-sam-01.txt

Ken discusses protecting the initial authentication using the local
host key and how it interacts with hardware preauth. One problem with
kerbeors-sam-01 is that it is insecure when used with RC4.

[15:00] Donna Skibbie, Kerberos LDAP schema
draft-skibbie-krb-kdc-ldap-schema-01.txt

There is general interest that this is good work; a fairly large group
has indicated specific interest. Leif asks why the information model
was removed from the base Kerberos spec (clarifications). Ken Raeburn
replies that it was overly MIT specific, and there's general consensus
that a general information model would be a good thing.

Donna asks people to contact her if you want to be added to the
Kerberos-ldap-schema-list. Leif pointed out: There was also discussions 
about aligning krb password policy with ldap password policy schema.

[15:08] done, 8 minutes overtime.

-- 

 Douglas E. Engert  <[email-masked]>
 Argonne National Laboratory
 9700 South Cass Avenue
 Argonne, Illinois  60439 
 (630) 252-5444