From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matthew Garrett Subject: Re: [PATCH] x86/efi: pull NV+BS variables out before we exit boot services Date: Tue, 19 Mar 2013 18:28:10 +0000 Message-ID: <20130319182810.GA13003@srcf.ucam.org> References: <1363596014.2412.8.camel@dabdike.int.hansenpartnership.com> <20130319014850.GA28934@srcf.ucam.org> <1363680885.2377.11.camel@dabdike.int.hansenpartnership.com> <20130319163531.GA10879@srcf.ucam.org> <1363713447.2377.60.camel@dabdike.int.hansenpartnership.com> <20130319172506.GA11969@srcf.ucam.org> <1363717411.2377.68.camel@dabdike.int.hansenpartnership.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1363717411.2377.68.camel-sFMDBYUN5F8GjUHQrlYNx2Wm91YjaHnnhRte9Li2A+AAvxtiuMwx3w@public.gmane.org> Sender: linux-efi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: James Bottomley Cc: linux-efi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel List-Id: linux-efi@vger.kernel.org On Tue, Mar 19, 2013 at 06:23:31PM +0000, James Bottomley wrote: > The scheme we discussed, unless something radically changed, was to > convey a temporary key pair via a mechanism to later verify the > hybernate kernel on a resume. That only requires reboot safe knowledge > of the public key. The private key can be conveyed in BS only (not NV), > and should be consumed (as in deleted) by the OS when it receives it, so > it wouldn't be exposed by this patch. It requires the key to survive the system being entirely powered down, which means it needs to be BS+NV. It shouldn't be possible for userspace to access this key. -- Matthew Garrett | mjg59-1xO5oi07KQx4cg9Nei1l7Q@public.gmane.org