From: Pavel Machek <pavel-ynQEQJNshbs@public.gmane.org>
Subject: Re: [RFC PATCH 00/18 v3] Signature verification of hibernate
 snapshot
Date: Thu, 29 Aug 2013 23:32:50 +0200
Message-ID: <20130829213249.GA25940@amd.pavel.ucw.cz>
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Hi!

> > >    - Bootloader store the public key to EFI boottime variable by itself
> > >    - Bootloader put The private key to S4SignKey EFI variable for forward to
> > >      kernel.
> > 
> > Is the UEFI NVRAM really suited for such regular updates?
> > 
> 
> Yes, Matthew raised this concern at before. I modified patch to load
> private key in efi stub kernel, before ExitBootServices(), that means we
> don't need generate key-pair at every system boot. So, the above
> procedure of efi bootloader will only run one time. 
> 
> User can enable SNAPSHOT_REGEN_KEYS kernel config to notify efi
> booloader regenerate key-pair for every S4 to improve security if he
> want. So, the key-pair re-generate procedure will only launched when S4
> resume, not every system boot.

How many writes can UEFI NVRAM survive? (Is it NOR?)

"every S4 resume" may be approximately "every boot" for some users...
									Pavel
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