Re: [TLS] I-D Action: draft-ietf-tls-negotiated-ff-dhe-10.txt

Ilari Liusvaara <ilari.liusvaara@elisanet.fi> Wed, 03 June 2015 17:57 UTC

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Date: Wed, 3 Jun 2015 20:57:13 +0300
From: Ilari Liusvaara <ilari.liusvaara@elisanet.fi>
To: Daniel Kahn Gillmor <dkg@fifthhorseman.net>
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Subject: Re: [TLS] I-D Action: draft-ietf-tls-negotiated-ff-dhe-10.txt
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On Wed, Jun 03, 2015 at 01:48:39PM -0400, Daniel Kahn Gillmor wrote:
> 
> For TLS 1.3, i'm expecting that any FFDHE ciphersuites will have a
> radically different handshake, so very little of this is relevant (plus,
> it will be TLS 1.3, so we can treat the existing ciphersuites
> differently based on the version of the protocol in use).  So the
> negotiated-ff-dhe draft aimed for the simplest, most minimal change for
> 1.2 and earlier.

On protocol level, in TLS 1.3-latest, the only difference between DHE
and ECDHE appears to be that DHE has 2-byte length filed, while ECDHE
has 1-byte length field (and both then are packed alone into variable-
length field with redundant 2-byte length field...).


-Ilari