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Re: [TLS] Computation of static secret in anonymous DH

Hubert Kario <hkario@redhat.com> Mon, 29 June 2015 11:46 UTC

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From: Hubert Kario <hkario@redhat.com>
To: tls@ietf.org
Date: Mon, 29 Jun 2015 13:46:18 +0200
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Subject: Re: [TLS] Computation of static secret in anonymous DH
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On Friday 26 June 2015 12:51:01 Eric Rescorla wrote:
> On Fri, Jun 26, 2015 at 12:47 PM, Ilari Liusvaara <
> 
> ilari.liusvaara@elisanet.fi> wrote:
> > On Fri, Jun 26, 2015 at 12:31:01PM -0700, Eric Rescorla wrote:
> > > Note: I have updated the WIP (and that's what I sent to Hugo) so it now
> > > contains the
> > > changes the values Hugo describes.
> > 
> > Small nit:
> > 
> > master_secret= HKDF(xSS, xES, "master secret")
> > 
> > Should that be:
> > 
> > master_secret= HKDF(xSS, xES, "master secret", L)
> > 
> > (the length parameter is seemingly missing)?
> 
> Yes, thanks for the correction.
> 
> > Also, is that label NUL-terminated or not (I think it is)? Another
> > reason why I think it is not a good idea to use notes to change
> > meaning of explcit algorithms...
> 
> They are all NUL-terminated.

Isn't this a departure from TLS1.0 up to TLS1.2?

I don't think this is a good idea...
 
-- 
Regards,
Hubert Kario
Quality Engineer, QE BaseOS Security team
Web: www.cz.redhat.com
Red Hat Czech s.r.o., Purkyňova 99/71, 612 45, Brno, Czech Republic

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