Messages in this thread | | | Date | Tue, 19 Mar 2013 18:50:03 +0000 | From | Matthew Garrett <> | Subject | Re: [PATCH] x86/efi: pull NV+BS variables out before we exit boot services |
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On Tue, Mar 19, 2013 at 06:40:56PM +0000, James Bottomley wrote: > On Tue, 2013-03-19 at 18:28 +0000, Matthew Garrett wrote: > > 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. > > It requires the *public* key to survive power down, certainly. The > private key can be thrown away once the hibernate image is signed. I > think the scheme can be constructed so the private key is never in NV > storage ... that also makes it more secure against tampering.
Well, that somewhat complicates implementation - we'd be encrypting the entire contents of memory except for the key that we're using to encrypt memory. Keeping the public key away from userspace avoids having to care about that.
-- Matthew Garrett | mjg59@srcf.ucam.org
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