Re: [TLS] WGLC: draft-ietf-tls-session-hash

Nico Williams <nico@cryptonector.com> Mon, 24 November 2014 10:44 UTC

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Date: Mon, 24 Nov 2014 04:44:43 -0600
From: Nico Williams <nico@cryptonector.com>
To: Adam Langley <agl@imperialviolet.org>
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Subject: Re: [TLS] WGLC: draft-ietf-tls-session-hash
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On Mon, Nov 24, 2014 at 02:36:22AM -0800, Adam Langley wrote:
> On Mon, Nov 24, 2014 at 12:44 AM, Yoav Nir <ynir.ietf@gmail.com> wrote:
> > Third issue: Why can’t an attacker disable this protection by simply
> > omitting the extension from both its ClientHello and ServerHello?
> 
> Writing this down might be called for too. In practice, I'm
> implementing it so that calls to get tls-unique values and the like
> will fail on resumed connections where the original session did not
> use this extension.

+1.