Re: Linux guest kernel threat model for Confidential Computing

From: Richard Weinberger
Date: Thu Jan 26 2023 - 09:25:13 EST


On Wed, Jan 25, 2023 at 3:22 PM Daniel P. Berrangé <berrange@xxxxxxxxxx> wrote:
> Any virtual device exposed to the guest that can transfer potentially
> sensitive data needs to have some form of guest controlled encryption
> applied. For disks this is easy with FDE like LUKS, for NICs this is
> already best practice for services by using TLS. Other devices may not
> have good existing options for applying encryption.

I disagree wrt. LUKS. The cryptography behind LUKS protects persistent data
but not transport. If an attacker can observe all IO you better
consult a cryptographer.
LUKS has no concept of session keys or such, so the same disk sector will
always get encrypted with the very same key/iv.

--
Thanks,
//richard