Re: Linux guest kernel threat model for Confidential Computing

Dr. David Alan Gilbert
2023-01-26T14:58:44Z

* Richard Weinberger (richard.weinberger@gmail.com) wrote:
> On Wed, Jan 25, 2023 at 3:22 PM Daniel P. Berrangé <berrange@redhat.com> 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.

Are you aware of anything that you'd use instead?

Are you happy with dm-verity for protection against modification?

Dave

> --
> Thanks,
> //richard
>
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK