[OpenAFS] fs setcrypt and transarc

[Chaskiel M Grundman]

--On Thursday, April 10, 2003 13:32:26 -0400 Ted Anderson
<TedAnderson@mindspring.com> wrote:

 
> Originally, the purpose of the ticket's session key was to encrypt the
> session.  Can you elaborate on this "current conventional wisdom" or
> provide a pointer?


Sorry. The actual problem is that the same key is used for every session,
opening up the possibility of replay attacks, or of combining knowlege from
sniffing multiple sessions to possibly learn stuff about the key. (I really
don't know how dangerous it is, nor can I argue about it one way or
another.  It's possible that someone else will volunteer to argue.)

It's mentioned in
http://www.ietf.org/internet-drafts/draft-ietf-krb-wg-crypto-04

and even a bit in an old paper by Bellovin and Merritt (I only have a
reference to an abstract):
http://www.stanford.edu/~emrek/quals/summaries/Limitations_of_the_Kerberos_
Protocol-Bellovin-1990