krb enctype presentation available

[Will Fiveash]

On Thu, Jun 30, 2005 at 06:25:08PM -0500, Will Fiveash wrote:
> On Thu, Jun 30, 2005 at 05:21:40PM -0400, Ken Hornstein wrote:
> > >I created a presentation PDF a while back that I've placed on the Web
> > >which goes into detail on Kerberos enctypes in terms of how they are
> > >used, negotiated and controlled via *.conf parameters.  It can be
> > >downloaded via my blog:
> > >
> > >http://blogs.sun.com/roller/page/wfiveash?entry=everything_you_wanted_to_know
> > 
> > This is a good presentation.  I have two comments:
> > 
> > - In my experience, encryption type settings are the herpes of the Kerberos
> >   world - once they get out "into the wild", they spread magically to
> >   other systems and it's damn hard to get rid of them.  If you have
> >   your applicatation server enctypes set correctly, you should almost
> >   never need them.  I'd stress that setting these enctype settings on
> >   the client should only be used rarely (say, you're using MIT Kerberos
> >   that supports AES, but one of your developers uses a Java Kerberos
> >   implementation that only supports single-DES).  I know you mention this
> >   in your last slide, but I'd put something stronger in there.
> 
> Yeah, I'll stress doing the "right thing" more as this is one of the
> reasons I created the presentation (helping admins understand the entype
> knobs to get it right or at least leave well enough alone).
> 
> > - I know you know this, but on slide 8 you imply with the diagrams that
> >   the ticket in the AS_REP is double-encrypted, and of course it's not;
> >   only the session key and a few other bits are encrypted by the user's
> >   long-term key.  A minor nit, but I only wanted to point it out for
> >   accuracy's sake.
> 
> Thanks for the feedback.  I'll tweak the presentation to make it more
> accurate.

I've updated my presentation.  Note, the previous version had a bogus
"Sun Confidential" label at the bottom of the slides.  I've removed that
in the current version.  Sorry about that.

-- 
Will Fiveash
Sun Microsystems Inc.
Austin, TX, USA (TZ=CST6CDT)