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Re: [TLS] PR for anti-downgrade mechanism

Brian Smith <brian@briansmith.org> Fri, 16 October 2015 22:34 UTC

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Date: Fri, 16 Oct 2015 12:34:28 -1000
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From: Brian Smith <brian@briansmith.org>
To: Martin Thomson <martin.thomson@gmail.com>
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Cc: Karthikeyan Bhargavan <karthik.bhargavan@gmail.com>, "tls@ietf.org" <tls@ietf.org>
Subject: Re: [TLS] PR for anti-downgrade mechanism
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On Fri, Oct 16, 2015 at 12:12 PM, Martin Thomson <martin.thomson@gmail.com>
wrote:

> On 16 October 2015 at 13:39, Brian Smith <brian@briansmith.org> wrote:
> > That would be especially true for an implementation that does False Start
> > for TLS 1.2.
>
> I don't see how false start plays into this.  We could have clients
> reject false start if they see this sentinel value.  But don't we want
> to just treat this as an attack and abort instead?
>

Yes. The client needs the sentinel to know to abort the connection, if its
willing to false start with TLS 1.2 when it also support TLS 1.3, right?

Cheers,
Brian
-- 
https://briansmith.org/

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