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

Yoav Nir <ynir.ietf@gmail.com> Thu, 02 June 2016 08:39 UTC

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From: Yoav Nir <ynir.ietf@gmail.com>
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Date: Thu, 2 Jun 2016 11:39:20 +0300
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To: Nikos Mavrogiannopoulos <nmav@redhat.com>
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Subject: Re: [TLS] no fallbacks please [was: Downgrade protection, fallbacks, and server time]
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> On 2 Jun 2016, at 10:31 AM, Nikos Mavrogiannopoulos <nmav@redhat.com>; wrote:
> 
> On Wed, 2016-06-01 at 15:43 -0700, Eric Rescorla wrote:
>> 2% is actually pretty good, but I agree that we're going to need
>> fallback.
> 
> Please not. Lets let these fallbacks die. Not every client is a
> browser. TLS 1.3 must be a protocol which doesn't require hacks to
> operate. CBC was removed, lets do the same for insecure fallbacks.
 
Not every client is a browser, but some are. So what does the browser do when a server resets the connection after seeing the ClientHello?

Blank screen with a failure message?