Re: [Qemu-devel] Emulation of TCG OPAL self-encrypting drive

[David Kozub]

On Mon, 7 Jan 2019, Stefan Hajnoczi wrote:

> QEMU supports LUKS encrypted disk images so no new code is needed for
> the actual encryption.

Thanks for the feedback, Stefan. I know very little about qemu internals 
(I looked around a bit). One issue is: OPAL needs some persistent data 
outside of the actual user-visible data. How does that fit in with storage 
in QEMU? Perhaps the implementation could just occupy a fixed size of the 
associated storage for the OPAL state.

> > Or, just a pass-through to a block device in the host - but a pass-through
> > that would allow OPAL commands.
>
> You can pass through a storage controller using PCI passthrough or you
> can pass through a SCSI LUN, but there is no ATA passthrough.

I currently don't have a usable box for PCI passthrough. I'm thinking 
that ATA passthrough could be generally usable for any fiddling and 
perhaps not too difficult to implement.

If I understand QEMU sources correctly, this needs to touch hw/ide/core.c 
(ide_exec_cmd), either adding a layer for OPAL, or just forwarding ATA 
commands for pass-through. Right?

Best regards,
David