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Re: [TLS] HKDF

Michael StJohns <msj@nthpermutation.com> Thu, 26 March 2015 14:57 UTC

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Date: Thu, 26 Mar 2015 10:55:48 -0400
From: Michael StJohns <msj@nthpermutation.com>
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Subject: Re: [TLS] HKDF
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On 3/26/2015 3:24 AM, Ilari Liusvaara wrote:
> Turns out you can't even implement TLS fully in design that does not
> know about TLS,

This is true for TLS1.2 and before, mainly because of the master secret 
expansion and the PRF.  Everything else is bog standard crypto.

> nor does it seem one can even change TLS so that
> would be possible (at least without introducing gaping security holes).

I don't know that I believe that.  TLS is a protocol wrapped around a 
set of cryptographic constructs.  There are ways to use standard 
constructs in TLS to build a secure protocol.   It will require some 
surgery on TLS1.2, but I think that's well underway.

Mike

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