Re: [TLS] confirming the room’s consensus: adopt HKDF PRF for TLS 1.3

Ilari Liusvaara <ilari.liusvaara@elisanet.fi> Wed, 01 April 2015 19:48 UTC

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Date: Wed, 1 Apr 2015 22:48:50 +0300
From: Ilari Liusvaara <ilari.liusvaara@elisanet.fi>
To: Russ Housley <housley@vigilsec.com>
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Subject: Re: [TLS] =?utf-8?q?confirming_the_room=E2=80=99s__consensus=3A_adopt?= =?utf-8?q?_HKDF_PRF_for_TLS_1=2E3?=
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On Wed, Apr 01, 2015 at 03:19:33PM -0400, Russ Housley wrote:
> 
> One detail that was not discussed because we were running out of
> time is important to me (and may be important to others).  SHA-256
> would be the MTI.  Is an alternative hash function chosen based on
> the cipher suite or some other mechanism?

In TLS 1.2 and 1.3-current, the main PRF-hash is designated by
the ciphersuite. I have not seen any proposals to change this.

Then there is signature hash, which is negotiated using
extensions.


-Ilari