Re: [TLS] A la carte handshake negotiation

Ilari Liusvaara <ilari.liusvaara@elisanet.fi> Mon, 29 June 2015 06:27 UTC

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Date: Mon, 29 Jun 2015 09:26:59 +0300
From: Ilari Liusvaara <ilari.liusvaara@elisanet.fi>
To: Daniel Kahn Gillmor <dkg@fifthhorseman.net>
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Subject: Re: [TLS] A la carte handshake negotiation
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On Sun, Jun 28, 2015 at 06:38:28PM -0400, Daniel Kahn Gillmor wrote:
> On Sun 2015-06-28 03:44:03 -0400, Ilari Liusvaara wrote:
> > Also, out of 6 points for kex/aux
> 
> I think you mean kex/auth here, right?  i'm just asking for the sake of
> clarity; this conversation has lots of slightly divergent shorthand
> notation thrown around.

Yeah, a typo.
 
> > (after unifying DH, adding PSK and renaming PKIX to CERT), only 4 seem
> > sane:
> >
> > GDH+CERT
> > GDH+PSK
> > GDH+ANON
> > PSK+PSK
> >
> > KEY_TRANSPORT doesn't lead to anything sane without greatly different
> > key exchange.
> >
> > If new PAKE KEX would be added, it would add 2 combinations
> > fooPAKE+CERT and fooPAKE+ANON (6 for 7).
> 
> Doesn't PAKE provide authentication mechanism as well?  shouldn't at
> least one of these be fooPAKE+fooPAKE ?

Well, at least for SRP there are both cert (server authentication) and
no cert (verify possession of verifier) variants.


-Ilari