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Re: [CFRG] Comment on draft-irtf-cfrg-aead-limits-01

Eric Rescorla <ekr@rtfm.com> Tue, 17 November 2020 00:38 UTC

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From: Eric Rescorla <ekr@rtfm.com>
Date: Mon, 16 Nov 2020 16:38:09 -0800
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To: Stephen Farrell <stephen.farrell@cs.tcd.ie>
Cc: CFRG <cfrg@irtf.org>
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Subject: Re: [CFRG] Comment on draft-irtf-cfrg-aead-limits-01
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On Mon, Nov 16, 2020 at 4:27 PM Stephen Farrell <stephen.farrell@cs.tcd.ie>
wrote:

>
>
> On 17/11/2020 00:19, Eric Rescorla wrote:
> > I'm not following you here. This draft is about the lifetime of symmetric
> > keys, which you can automate.
>
> "Can" - sure. But while I'm open to correction, I believe
> lots of small embedded systems using TLS and the like, and
> maybe still cookie and/or token generating chunks of code,
> do not.
>
> With TLS or similar, at the point where the developer's
> code has decided it's time to re-key, then the HOWTO is
> automated. But the decision to do the re-key isn't.
>

What stops the TLS or QUIC stack from rekeying internally
when it hits the limit without even notifying the developer.

-Ekr

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