Auto-rekey? (was Re: GSSAPI/Kerberos support in OpenSSH 3.1p1)

Nicolas Williams Nicolas.Williams at
Sat Mar 23 02:49:57 EST 2002

A thought occurs: have the client attempt to automatically initiate
re-keying when the GSS context is due to expire or, if expired, every
few minutes.

Let me be more specific.

The way SSH gsskeyex works GSS context expiration is unimportant, but
GSS context expiration is a clue on a tip as to when forwarded
credentials expire. It would be useful if credentials were re-forwarded
automatically when refreshed. The way one re-forwards GSS credentials
with SSH gsskeyex is by re-keying the session.

The client can find out from gss_init_sec_context() when the context
and any forwarded credentials, will expire. The client can check, when
the time comes, and periodically thereafter, if new credentials are
available, and if so, re-key the SSH session.

To make this happen would require a hook in the client loop (but NOT a
select() timeout).

This way one need only kinit in one place and tickets will eventually be
re-forwarded automatically.

Is there any interest in such a feature? Advice?



On Thu, Mar 21, 2002 at 10:29:35PM +0000, Simon Wilkinson wrote:
> I've now completed updating my patches for GSSAPI in protocol v2 to
> OpenSSH 3.1p1
> See
> Cheers,
> Simon.
> _______________________________________________
> openssh-unix-dev at mailing list
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