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

Russ Housley <housley@vigilsec.com> Wed, 01 April 2015 19:20 UTC

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From: Russ Housley <housley@vigilsec.com>
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Date: Wed, 1 Apr 2015 15:19:33 -0400
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Subject: Re: [TLS] =?windows-1252?q?confirming_the_room=92s_consensus=3A_adopt?= =?windows-1252?q?_HKDF_PRF_for_TLS_1=2E3?=
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The hum in the room showed overwhelming support for HKDF.

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?

Russ


On Apr 1, 2015, at 2:00 PM, Sean Turner wrote:

> This message is to confirm the consensus reached @ the IETF 92 TLS session in Dallas and at the TLS Interim in Seattle to make the TLS 1.3 PRF be an HKDF-based PRF (see http://datatracker.ietf.org/doc/rfc5869/?include_text=1).
> 
> Please indicate whether or not you agree with the consensus by 2015-04-17.  If not, please indicate why.  Also, please note that we’re interested in uncovering new issues not rehashing issues already discussed.
> 
> Thanks - J&S
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