Re: [TLS] no fallbacks please [was: Downgrade protection, fallbacks, and server time]

Hubert Kario <hkario@redhat.com> Fri, 03 June 2016 09:28 UTC

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From: Hubert Kario <hkario@redhat.com>
To: tls@ietf.org
Date: Fri, 03 Jun 2016 11:28:05 +0200
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Subject: Re: [TLS] no fallbacks please [was: Downgrade protection, fallbacks, and server time]
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On Friday 03 June 2016 08:37:34 Nikos Mavrogiannopoulos wrote:
> A simpler proposal is:
> Consider TLS 1.3 as a feature, and negotiate it using an empty
> extension. If the extension is present a server assumes TLS 1.3.

If anything, it should be this.

Extension with version negotiation introduced because version 
negotiation is commonly gotten wrong doesn't look like a solution to 
me...

That being said, I would prefer the solution to be a compliance test 
suite that checks if servers do handle correctly future versions, future 
extensions and future ciphersuites correctly.
-- 
Regards,
Hubert Kario
Senior Quality Engineer, QE BaseOS Security team
Web: www.cz.redhat.com
Red Hat Czech s.r.o., Purky┼łova 99/71, 612 45, Brno, Czech Republic