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Re: [TLS] Encrypting record headers: practical for TLS 1.3 after all?

mrex@sap.com (Martin Rex) Wed, 02 December 2015 16:08 UTC

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To: Jacob Appelbaum <jacob@appelbaum.net>
Date: Wed, 02 Dec 2015 17:08:37 +0100
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From: mrex@sap.com
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Subject: Re: [TLS] Encrypting record headers: practical for TLS 1.3 after all?
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Jacob Appelbaum wrote:
> 
> I hope that we'll hide the SNI data by default and I understand that a
> discussion about encrypted SNI is currently scheduled for some point
> in the future.

Hiding SNI data is completely silly security-wise, and any TLSv1.2
backwards-compatible ClientHello must include a plaintext visible SNI.

So your client will have to know a-priori, out-of-band or be configured
to TLSv1.3-only in order to avoid using a TLSv1.2-compatible ClientHello
with cleartext SNI.

-Martin

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