Re: [TLS] draft-green-tls-static-dh-in-tls13-01

Stephen Farrell <stephen.farrell@cs.tcd.ie> Fri, 07 July 2017 21:16 UTC

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To: Russ Housley <housley@vigilsec.com>
Cc: IETF TLS <tls@ietf.org>, Matthew Green <matthewdgreen@gmail.com>
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From: Stephen Farrell <stephen.farrell@cs.tcd.ie>
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Subject: Re: [TLS] draft-green-tls-static-dh-in-tls13-01
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Hiya,

On 07/07/17 22:12, Russ Housley wrote:
> Stephen:
> 
>> You didn't refer to 2804 and the standards track. As an author do
>> you really think this can be on the standards track and yet not
>> obsolete 2804?
> 
> Yes. 

We disagree.

> Section 3 of RFC 2804 offers pretty clear definition of
> wiretapping, and that is not what is going on here.  In this
> situation, all of the parties are part of the same organization,
> under common key management.  

That is one possible deployment. There is nothing in this
proposal that limits it's use to that.

> The server must explicitly accept and
> use the centrally managed (EC)DH key, so that party is completely
> aware and, in fact, enabling the other parties to decrypt the
> traffic.

Yes, and the server could equally be compelled to do that,
in which case this technology would clearly be a standard
form of wiretapping.

Claiming that is not the case would be incredible so I have
no idea how you maintain that this isn't in conflict with
2804.

S.

> 
> Russ
> 
>