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

Eric Rescorla <ekr@rtfm.com> Mon, 24 August 2015 21:40 UTC

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From: Eric Rescorla <ekr@rtfm.com>
Date: Mon, 24 Aug 2015 14:39:40 -0700
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To: Paul Wouters <paul@nohats.ca>
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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 2:33 PM, Paul Wouters <paul@nohats.ca>; wrote:

> On Mon, 24 Aug 2015, Eric Rescorla wrote:
>
> TLS 1.3 encrypts both the client's and server's certificates already.
>> The server's certificate is secure only against passive attack.
>>
>
> Not having read the TLS 1.3 draft, in IKE parties can send a hash of the
> CAs they trust, so unless you receive a hash of a known CA to you, you
> can withold your own certificate from being sent.
>
> Is a similar mechanism not planned for TLS 1.3?


Well, TLS already permits the server to indicate the DN of CAs which should
be in the path. I have not heard of any plan to add a digest indication.

-Ekr