RE: [PATCH v4 3/3] block/rbd: Add support for layered encryption

[Or Ozeri]

> -----Original Message-----
> From: Daniel P. Berrangé <berrange@redhat.com>
> Sent: Thursday, 12 January 2023 14:50
> To: Or Ozeri <ORO@il.ibm.com>
> Cc: qemu-devel@nongnu.org; qemu-block@nongnu.org; Danny Harnik
> <DANNYH@il.ibm.com>; idryomov@gmail.com
> Subject: [EXTERNAL] Re: [PATCH v4 3/3] block/rbd: Add support for layered
> encryption
> 
> I don't think we should be reporting this differently.
> 
> The layering is not a different encryption format. It is a configuration
> convenience to avoid repeating the same passphrase for a stack of images
> when opening an image.
> 
> In terms of encryption format it is still either using 'luks1' or 'luks2'.
> 

I don’t think that's right.
The simplest argument is that the magic for RBD layered-luks is not "LUKS".
So, it's a different format, which cannot be opened by dm-crypt for example.
I think this is important for the user to know that, and thus it is useful to 
point it out
in the output of qemu-img info.