Re: Fixing exchange of host keys in the SSH key exchange

Mouse <mouse@Rodents-Montreal.ORG> Thu, 06 April 2017 20:35 UTC

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Date: Tue, 4 Apr 2017 18:06:58 -0400 (EDT)
From: Mouse <mouse@Rodents-Montreal.ORG>
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To: ietf-ssh@NetBSD.org
Subject: Re: Fixing exchange of host keys in the SSH key exchange
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> if I may stick an oar in sideways: if you go to all the trouble,
> could you add a mechanism by which the server could advise that the
> host key used by the client was still valid but deprecated, and to
> download the new host key once connected?

That actually is a very interesting argument I hadn't thought of for
something operationally like the proposed scheme: it permits the server
to support multiple host keys at once for a single algorithm.  (The
client, of course, already can, since in the current design it's the
one judging host key validity.)

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