Re: [TLS] [ECH] Reverting the config ID change

Stephen Farrell <stephen.farrell@cs.tcd.ie> Wed, 17 February 2021 16:25 UTC

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To: Eric Rescorla <ekr@rtfm.com>
Cc: Christopher Wood <caw@heapingbits.net>, "TLS@ietf.org" <tls@ietf.org>
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From: Stephen Farrell <stephen.farrell@cs.tcd.ie>
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Date: Wed, 17 Feb 2021 16:24:55 +0000
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Subject: Re: [TLS] [ECH] Reverting the config ID change
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On 17/02/2021 16:00, Eric Rescorla wrote:
> On Tue, Feb 16, 2021 at 4:44 PM Stephen Farrell <stephen.farrell@cs.tcd.ie>
> wrote:
> 
>>
>>
>> On 17/02/2021 00:34, Eric Rescorla wrote:
>>> How is it any harder to manage a multi-octet server-chosen value than a
>>> single-octet server-chosen value?
>>
>> Easier for the library on the server side. If it's >1 octet
>> then someone will want some semantics. If ==1 then they'll
>> have to accept none and possible collisions so it can be
>> handled independently inside the library.
>>
> 
> The server is free to enforce 1 byte.

A server operator would be free to do that. The person
writing the code likely would not be as some server
operator would also be free to try impose semantics
on a multibyte field.

S.


> 
> -Ekr
>