Re: [TLS] A la carte handshake negotiation

Viktor Dukhovni <ietf-dane@dukhovni.org> Fri, 12 June 2015 15:38 UTC

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Date: Fri, 12 Jun 2015 15:38:05 +0000
From: Viktor Dukhovni <ietf-dane@dukhovni.org>
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References: <201506111558.21577.davemgarrett@gmail.com> <20150612145820.GR2050@mournblade.imrryr.org> <201506121114.47527.davemgarrett@gmail.com>
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Subject: Re: [TLS] A la carte handshake negotiation
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On Fri, Jun 12, 2015 at 11:14:47AM -0400, Dave Garrett wrote:

> > > * TLS 1.3 would only negotiate suites prefixed with ECDHE_ECDSA or ECDHE_PSK.
> > 
> > Where are anonymous (ADH and AECDH) suites?
> 
> Still in the spec. I currently have usage of ECDHE_ECDSA or ECDHE_PSK as
> a "SHOULD", with "MUST NOT" for the explicitly deprecated bits. Anon is
> effectively a "SHOULD NOT". I don't think we can have an absolute mandate
> for only certain prefixes with a "MUST", as that would exclude new ones
> in the future. (e.g. a post-quantum key exchange will likely want to be
> negotiated with a separate cipher suite)

Just to confirm, it will be possible to negotiate AECDH and ADH
key exchange ala carte, separately from the bulk cipher, right?

-- 
	Viktor.