From: Vojtech Pavlik <vojtech-AlSwsSmVLrQ@public.gmane.org>
Subject: Re: [RFC V4 PATCH 00/15] Signature verification of hibernate snapshot
Date: Thu, 26 Sep 2013 14:23:03 +0200
Message-ID: <20130926122303.GB30225@suse.cz>
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Cc: Pavel Machek <pavel-+ZI9xUNit7I@public.gmane.org>, joeyli <jlee-IBi9RG/b67k@public.gmane.org>,
	Alan Stern <stern-nwvwT67g6+6dFdvTe/nMLpVzexx5G7lz@public.gmane.org>,
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	James Bottomley <james.bottomley-JuX6DAaQMKPCXq6kfMZ53/egYHeGw8Jk@public.gmane.org>,
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	Herbert Xu <herbert-F6s6mLieUQo7FNHlEwC/lvQIK84fMopw@public.gmane.org>,
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To: Michal Marek <mmarek-AlSwsSmVLrQ@public.gmane.org>
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In-Reply-To: <524426C3.1050501-AlSwsSmVLrQ@public.gmane.org>

On Thu, Sep 26, 2013 at 02:21:23PM +0200, Michal Marek wrote:

> > Is not it as simple as storing hash of hibernation image into NVRAM
> > and then verifying the hash matches the value in NVRAM on next
> > startup? No encryption needed. 
> 
> I think that part of the exercise is to minimize the number of writes to
> the NVRAM. The hash changes with every hibernation, obviously.

The key should, too. 

-- 
Vojtech Pavlik
Director SUSE Labs