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

Nico Williams <nico@cryptonector.com> Sun, 09 July 2017 19:15 UTC

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Date: Sun, 9 Jul 2017 14:15:37 -0500
From: Nico Williams <nico@cryptonector.com>
To: Matthew Green <matthewdgreen@gmail.com>
Cc: tls@ietf.org
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Subject: Re: [TLS] draft-green-tls-static-dh-in-tls13-01
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I don't understand this proposal at all.  You absolutely can build in
wiretapping capabilities into TLS server implementations without any
help from the TLS protocol.

(E.g., your servers could send a multicast UDP datagram for each
session/connection, bearing metadata and master keys encrypted to a
logging facility's public key, or in a logging session key.  If UDP be
insufficiently reliable for your needs, then use TCP.  Yes, there's
overhead in this, but it's minimal, and you already need fast logging
facilities anyways.)

Changing the TLS protocol to aid in wiretapping risks introducing
vulnerabilities in the protocol.

Nico
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