Re: [TLS] Privacy considerations - identity hiding from eavesdropping in (D)TLS

Eric Rescorla <ekr@rtfm.com> Mon, 24 August 2015 21:18 UTC

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From: Eric Rescorla <ekr@rtfm.com>
Date: Mon, 24 Aug 2015 14:17:20 -0700
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To: "Viktor S. Wold Eide" <viktor.s.wold.eide@gmail.com>
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Subject: Re: [TLS] Privacy considerations - identity hiding from eavesdropping in (D)TLS
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On Mon, Aug 24, 2015 at 1:56 PM, Viktor S. Wold Eide <
viktor.s.wold.eide@gmail.com>; wrote:

> Hi,
>
> I am looking for a way to achieve identity hiding for DTLS 1.2, which also
> hopefully can be used in (D)TLS 1.3, when available.
>
> From what I understand, for (D)TLS 1.2 it would be possible to perform an
> anonymous unencrypted handshake and then to renegotiate the connection with
> authentication within the encrypted channel, e.g., according to the expired
> draft [1]. From the latest TLS 1.3 draft [2] it appears that renegotiation
> will be removed in the upcoming 1.3 version.
>
> What is likely to be the recommended way to achieve identity hiding for
> (D)TLS 1.3, if any?
>
> [1] Transport Layer Security (TLS) Encrypted Handshake Extension,
> draft-ray-tls-encrypted-handshake-00, expired in 2012
> [2] The Transport Layer Security (TLS) Protocol Version 1.3,
> draft-ietf-tls-tls13-07
>
>
TLS 1.3 encrypts both the client's and server's certificates already.
The server's certificate is secure only against passive attack. The
client's is encrypted with a key that the client can authenticate as
belonging to the server.

-Ekr