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

Ilari Liusvaara <ilari.liusvaara@elisanet.fi> Fri, 26 June 2015 19:47 UTC

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Date: Fri, 26 Jun 2015 22:47:34 +0300
From: Ilari Liusvaara <ilari.liusvaara@elisanet.fi>
To: Eric Rescorla <ekr@rtfm.com>
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Subject: Re: [TLS] Computation of static secret in anonymous DH
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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)?


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...



-Ilari