Re: [secdir] secdir review of draft-ietf-curdle-gss-keyex-sha2-07

Hubert Kario <hkario@redhat.com> Thu, 03 January 2019 12:35 UTC

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From: Hubert Kario <hkario@redhat.com>
To: David Mandelberg <david@mandelberg.org>
Cc: Simo Sorce <simo@redhat.com>, draft-ietf-curdle-gss-keyex-sha2.all@ietf.org, iesg@ietf.org, secdir@ietf.org
Date: Thu, 03 Jan 2019 13:34:55 +0100
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Subject: Re: [secdir] secdir review of draft-ietf-curdle-gss-keyex-sha2-07
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On Tuesday, 1 January 2019 21:33:31 CET David Mandelberg wrote:
> On 1/1/19 9:06 AM, Simo Sorce wrote:
> > On Mon, 2018-12-31 at 14:57 -0500, David Mandelberg wrote:
> >> Section 5.1: When calculating H, are the boundaries between each
> >> concatenated thing clear? E.g., would V_C = "1.21" V_S = "0.1" and V_C =
> >> "1.2" V_S = "10.1" result in the same value for H?
> > 
> > All else equal I think it would
> 
> Ok. I don't have any specific attacks in mind, but that seems like a
> potential weak point. This probably isn't the right document to change
> that in though.

yes, we actually considered also making the key exchange secure against 
quantum computer attacks, but decided to favour ease of implementation as more 
important; thus the resulting minimal changes compared to RFC 4462

-- 
Regards,
Hubert Kario
Senior Quality Engineer, QE BaseOS Security team
Web: www.cz.redhat.com
Red Hat Czech s.r.o., Purky┼łova 115, 612 00  Brno, Czech Republic