Re: [TLS] ECH Padding

Stephen Farrell <stephen.farrell@cs.tcd.ie> Tue, 22 June 2021 22:12 UTC

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To: Christopher Patton <cpatton@cloudflare.com>
Cc: tls@ietf.org
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From: Stephen Farrell <stephen.farrell@cs.tcd.ie>
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Subject: Re: [TLS] ECH Padding
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On 22/06/2021 22:57, Christopher Patton wrote:
> Just to be clear, (1), (2) and (3) are not alternatives to the same
> problem. (1) solves client-side padding, whereas (2) and (3) are
> alternatives for solving server-side padding.

Apologies. (Though I put part of the blame on excessive
githubbery leading to a lack of clarity and ambiguity, as
is my habit:-)

I can live with (1) and (2) but only see any need to change
because of the QUIC argument(s) - absent those we can work
around things and get ECH out the door IMO.

(3) is a mistake - a new handshake message shouldn't be
adopted until after that's been tested and shown not to
be problematic and I bet it would be problematic as well
as lots more work

S.


>