On Thu, 25 Aug 2016, Rick van Rein wrote: > >>> Forwarding a TGT is bad because it is unbounded impersonation. > >> Only when the corresponding key is supplied alongside! [I hope I'm > >> not taking anything out of context by saying that, I'm not sure about > >> that but will probably be corrected if I am.] > > > > The TGT is all you need. It gives you access to all the resources the > > "real owner" has access to with no limitations. You do not need the long > > term key at all (until the TGT expires of course). > The TGT is a Ticket, holding EncryptedData. That encrypted portion > must be decrypted to get hold of the EncryptionKey contained in it. > Passing a TGT verbatim does not release this information, right? > > In user-to-user Kerberos, it is also possible to pass a TGT from the > service back to the client, and the client passes that verbatim without > being able to make heads or tails of it. That is what I meant. But I > may have been nitpicking, sorry about that.
You probably are nitpicking, yes, but I think the relevant key is the session key that is contained in the TGT -- only KDCs would have the key to decrypt the EncryptedData of the TGT (as opposed to the enc-part of the AS-REP which is where the client gets it). I assume that Simo is using "TGT" to mean "TGT and session key", as would be in a user's ccache, and not in the strict protocol data structure sense. -Ben ________________________________________________ Kerberos mailing list Kerberos@mit.edu https://mailman.mit.edu/mailman/listinfo/kerberos
