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Re: [TLS] Should we require compressed points

Ilari Liusvaara <ilari.liusvaara@elisanet.fi> Fri, 31 October 2014 18:31 UTC

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Date: Fri, 31 Oct 2014 20:31:46 +0200
From: Ilari Liusvaara <ilari.liusvaara@elisanet.fi>
To: Eric Rescorla <ekr@rtfm.com>
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Cc: Manuel Pégourié-Gonnard <mpg@polarssl.org>, "tls@ietf.org" <tls@ietf.org>
Subject: Re: [TLS] Should we require compressed points
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On Fri, Oct 31, 2014 at 10:34:52AM -0700, Eric Rescorla wrote:
> This discussion seems to be settling, so I've prepared a pull request
> that implements Bodo's suggestion:
> 
> https://github.com/tlswg/tls13-spec/pull/86
 
I think 8.1.2 (ECDHE premaster secret calculation) should be modified
as well, to specify using the fixed wire encoding of selected group for
premaster secret.

This is to avoid problems with more "odd" encodings.


Note that 8.1.1 does not quite match that beheviour, since it specifes
leading zero octets to be stripped (whereas DHE "element" encoding
doesn't seem to specify if zeroes are stripped or not)


-Ilari

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