Re: [TLS] Design Alternatives for Kerberos + DH

[Nikos Mavrogiannopoulos <[e-mail]>]

> ----- Original Message -----
>>> Hello,
>>> 3) Similar to OpenPGP: Negotiate cert-type
>>>
>>> There is a cert-type for X.509 and for OpenPGP; add one for Kerberos Tickets.
>>> PRO: Good integration with TLS: Tickets are transported in the
>>> ClientCertificate, and an Authenticator is the ClientVerify.  DH is
>>> independent and can move to the earlier phase for TLS 1.3.
>>> CON: Decision on client credential type must be made in ClientHello, when not
>>> all data may be available (namely, the sequence of tickets leading to the
>>> TLS-protected service).  Also impacts the cert-type used in the ServerCert.
>>
>> What messages do you need to transfer for Kerberos? Is it only a ping-pong? In that
>> case, do the supplemental data from RFC4680 provide a solution with PSK in TLS 1.2?
>>

> 4680 says "[a]ny such data MUST NOT need to be processed by the TLS
> protocol.", which seems to disqualify it from applicability here.

That's interesting and open to interpretation, but I don't think it is applicable.
If you simply use it to derive a key for PSK, it is equivalent to reading a key from
a password file using the username provided.

regards,
Nikos