Re: [TLS] AD review of draft-ietf-tls-negotiated-ff-dhe-08

Martin Thomson <martin.thomson@gmail.com> Wed, 01 April 2015 00:29 UTC

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Date: Tue, 31 Mar 2015 17:29:41 -0700
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From: Martin Thomson <martin.thomson@gmail.com>
To: Stephen Farrell <stephen.farrell@cs.tcd.ie>
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Subject: Re: [TLS] AD review of draft-ietf-tls-negotiated-ff-dhe-08
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On 31 March 2015 at 16:56, Stephen Farrell <stephen.farrell@cs.tcd.ie> wrote:
> #1 Have we tested in the wild that using elliptic_curves (10)
> in the ClientHello won't trigger some ECC code that causes
> handshakes to barf?

Firefox sends the supported_curves extension in every handshake and so
do most browsers.  So for those, the risk of intolerance is obviously
quite low.  That's not hard numbers obviously, but that's a lot of
ClientHello messages with the extension.