Re: [TLS] certificate_request_context

Hannes Tschofenig <hannes.tschofenig@gmx.net> Fri, 07 October 2016 09:45 UTC

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To: Martin Thomson <martin.thomson@gmail.com>, Ilari Liusvaara <ilariliusvaara@welho.com>
References: <3a6ce7fb-143a-2d67-6682-f221048aed49@gmx.net> <20161007083415.GA8456@LK-Perkele-V2.elisa-laajakaista.fi> <CABkgnnW3W6vk0AopaEMt=67nR49AHT2N4dgt_YxQkO4f8MUFSQ@mail.gmail.com>
From: Hannes Tschofenig <hannes.tschofenig@gmx.net>
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Date: Fri, 7 Oct 2016 11:45:07 +0200
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Cc: "<tls@ietf.org>" <tls@ietf.org>
Subject: Re: [TLS] certificate_request_context
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Hi Martin,

the problem is that with embedded implementations you need to be
prepared to receive this amount of data when the specification says so.


On 10/07/2016 10:59 AM, Martin Thomson wrote:
> On 7 October 2016 at 19:34, Ilari Liusvaara <ilariliusvaara@welho.com>; wrote:
>> If application supports any sort of multiplexing (e.g. HTTP/2), one
>> presumably wants the context to be non-opaque and identify the stream
>> that caused the request + some parameters about the request (to avoid
>> duplicating those in application layer).
> 
> 
> It's opaque to TLS.  And 255 simply establishes the number of octets
> in the length (1), if you don't need that much context (few will even
> if they implement this), don't use the extra space.
>