Re: [TLS] Data volume limits

Eric Rescorla <ekr@rtfm.com> Mon, 28 December 2015 20:11 UTC

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From: Eric Rescorla <ekr@rtfm.com>
Date: Mon, 28 Dec 2015 15:11:13 -0500
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To: Florian Weimer <fweimer@redhat.com>
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Subject: Re: [TLS] Data volume limits
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On Mon, Dec 28, 2015 at 3:08 PM, Florian Weimer <fweimer@redhat.com> wrote:

> On 12/21/2015 01:41 PM, Hubert Kario wrote:
>
> > if the rekey doesn't allow the application to change authentication
> > tokens (as it now stands), then rekey is much more secure than
> > renegotiation was in TLS <= 1.2
>
> You still have the added complexity that during rekey, you need to
> temporarily switch from mere sending or receiving to at least
> half-duplex interaction.
>

That's not intended. Indeed, you need to be able to handle the old key
in order to send/receive the KeyUpdate. Can you elaborate on your concern?

-Ekr