[dm-devel] [RFC PATCH 0/1] Add inline encryption support for dm-crypt

[Milan Broz]

On 13/01/2022 19:09, Israel Rukshin wrote:
> Hi,
> 
> I am working to add support for inline encryption/decryption
> at storage protocols like nvmf over RDMA. The HW that I am
> working with is ConnecX-6 Dx, which supports inline crypto
> and can send the data on the fabric at the same time.

This idea comes from time to time, and it makes dm-crypt bloated,
and mainly it moves responsibility for encryption to block layer
crypto.
It adds two completely different sector encryption paths there.

Also, see my comments here (for similar patches)
https://lore.kernel.org/dm-devel/c94d425a-bca4-8a8b-47bf-451239d29ebd@gmail.com/

I think dm-crypt should stay as SW crypto only (using kernel crypto API,
so HW acceleration is done through crypto drivers there).

A cleaner solution is to write a much simpler new dm-crypt-inline target,
which will implement only inline encryption.
(And userspace can decide which target to use.)
Code should be just an extension to the dm-linear target, most
of dm-crypt complexity is not needed here.

Also, please think about configuration - how do you want to configure it?

Just my opinion, it is, of course, up to DM maintainer if he takes such patches.

Thanks,
Milan