Re: [TLS] certificate_request_context

Martin Thomson <martin.thomson@gmail.com> Fri, 07 October 2016 08:59 UTC

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From: Martin Thomson <martin.thomson@gmail.com>
Date: Fri, 7 Oct 2016 19:59:43 +1100
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To: Ilari Liusvaara <ilariliusvaara@welho.com>
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Subject: Re: [TLS] certificate_request_context
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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.