Re: [TLS] New cipher suites for SRP

Schmidt, Jörn-Marc <Joern-Marc.Schmidt@secunet.com> Fri, 17 July 2015 08:38 UTC

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From: =?Windows-1252?Q?Schmidt=2C_J=F6rn-Marc?= <Joern-Marc.Schmidt@secunet.com>
To: Dan Harkins <dharkins@lounge.org>, Hubert Kario <hkario@redhat.com>
Thread-Topic: [TLS] New cipher suites for SRP
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Date: Fri, 17 Jul 2015 08:38:20 +0000
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Cc: "tls@ietf.org" <tls@ietf.org>, Geoffrey Keating <geoffk@geoffk.org>
Subject: Re: [TLS] New cipher suites for SRP
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>>  - Change the negotiation so that user name is not exchanged in the clear
>>  - Change key exchange to do PFS

>TLS-pwd already supports both of these. It also supports ECC too,
>which is problematic with the current SRP protocol.

I agree: Instead of modifying SRP I would prefer introducing a new PAKE
scheme. 
On CFRG I recently submitted a draft on requirements for such schemes
(https://www.ietf.org/mail-archive/web/cfrg/current/msg07005.html).

Or to be even more flexible - how about defining a generic way to include
PAKE in TLS to prevent a whole bunch of ExtensionTypes and CipherSuites by
merging them into one "PAKE_Auth"?

Best,

Jörn