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Re: draft-baushke-ssh-dh-group-sha2-01 (was Re: DH group exchange)

nisse@lysator.liu.se (Niels Möller ) Sun, 31 January 2016 21:22 UTC

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From: nisse@lysator.liu.se
To: Damien Miller <djm@mindrot.org>
Cc: "Mark D. Baushke" <mdb@juniper.net>, ietf-ssh@NetBSD.org, Peter Gutmann <pgut001@cs.auckland.ac.nz>, denis bider <ietf-ssh3@denisbider.com>, Jeffrey Hutzelman <jhutz@cmu.edu>, Stephen Farrell <stephen.farrell@cs.tcd.ie>, Jon Bright <jon@siliconcircus.com>, Simon Tatham <anakin@pobox.com>
Subject: Re: draft-baushke-ssh-dh-group-sha2-01 (was Re: DH group exchange)
References: <95389.1452676866@eng-mail01.juniper.net> <96437.1453915164@eng-mail01.juniper.net> <alpine.BSO.2.20.1601281001560.1003@natsu.mindrot.org>
Date: Fri, 29 Jan 2016 22:13:36 +0100
In-Reply-To: <alpine.BSO.2.20.1601281001560.1003@natsu.mindrot.org> (Damien Miller's message of "Thu, 28 Jan 2016 10:08:40 +1100 (AEDT)")
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Damien Miller <djm@mindrot.org> writes:

> I'd skip SHA-384 entirely in favour of SHA-512.

Agreed. SHA-384 has the same security as truncated SHA-512 (just
differing initial values). And I don't see any point in doing truncation
for the ssh key exchange hash, am I missing anything?

Regards,
/Niels

-- 
Niels Möller. PGP-encrypted email is preferred. Keyid C0B98E26.
Internet email is subject to wholesale government surveillance.

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