Re: [TLS] HTTPSSVC record draft - ESNI alternative for HTTPS

Stephen Farrell <stephen.farrell@cs.tcd.ie> Mon, 08 July 2019 22:28 UTC

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To: Erik Nygren <erik+ietf@nygren.org>
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From: Stephen Farrell <stephen.farrell@cs.tcd.ie>
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Date: Mon, 08 Jul 2019 23:27:57 +0100
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Subject: Re: [TLS] HTTPSSVC record draft - ESNI alternative for HTTPS
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I'm not sure what I think about the general idea TBH but
just on this bit...

On 08/07/2019 23:08, Erik Nygren wrote:
> 
> A downside is that this does add complexity for tools that operate entirely
> at the TLS layer such as openssl s_client that would be happier if only
> an ESNI record existed. 

I don't think that's such a big deal for the library as
that's unlikely to include the code to do DNS queries.
Being able to parse a couple of different wrappers for
ESNIKeys isn't that big a deal.

And at least the code I've done for s_client assumes it
gets the RR value on the command line (for now anyway)
so that's also no biggie. But I figure s_client isn't
that important as an application anwyay;-)

Having different DNS RRTYPEs one might need to probe
or otherwise know about would make like harder for
real application code that does DNS though, and for
servers who might end up having to publish the same
things in different ways. So I hope we don't create
that kind of problem.

Cheers,
S.