Re: [TLS] ESNIKeys over complex

Eric Rescorla <ekr@rtfm.com> Wed, 21 November 2018 02:35 UTC

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From: Eric Rescorla <ekr@rtfm.com>
Date: Tue, 20 Nov 2018 18:34:42 -0800
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To: "Salz, Rich" <rsalz@akamai.com>
Cc: Stephen Farrell <stephen.farrell@cs.tcd.ie>, "<tls@ietf.org>" <tls@ietf.org>
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Subject: Re: [TLS] ESNIKeys over complex
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On Tue, Nov 20, 2018 at 6:04 PM Salz, Rich <rsalz@akamai.com>; wrote:

> >    Sure a list of ciphersuites isn't bad. But the current
>     design has a set of keys and a set of ciphersuites and a
>     set of extensions and a set of Rdata values in the RRset.
>
> Since this is defined for TLS 1.3 with all known-good ciphers, can't that
> field be eliminated?
>

No, I don't think so. The server might choose to not support one of the TLS
1.3 ciphers, for instance. And even if that weren't true, how would we add
new ciphers?

-Ekr


> >    I'd bet a beer on such complexity being a source of bugs
>     every time.
>
> All sorts of aphorisms come to mind. :)
>
>     > This has a totally different expiry behavior from RRSIGs, so I'm
>     > not sure that's that useful an analogy.
>
>     Disagree. They're both specifying a time window for DNS data.
>     Same problems will arise is my bet.
>
> I am inclined to agree.
>
>
>
>