Re: [PATCH 0/3] Add support for qcrypto on shikra

[Eric Biggers <ebiggers@kernel.org>]

On Mon, May 25, 2026 at 09:28:43AM -0500, Eric Biggers wrote:
> ARMv8 Crypto Extensions are "hardware" as well, just in the CPU.  They
> provide constant-time execution, for example.
> 
> Granted, they don't protect from power analysis and electromagnetic
> emanation attacks.  Does QCE actually provide those protections, though?
> 
> Either way, it doesn't really matter in this case.  There are multiple
> aspects to security, and before even considering these advanced
> protections, the basics of security need to be absolutely solid.  That
> is, the driver needs to always compute the crypto algorithms correctly,
> and it needs to be completely robust when fuzzed by unprivileged
> userspace (because it can accessed in that way).

Looks like these protections are not even present either.  From
https://csrc.nist.gov/CSRC/media/projects/cryptographic-module-validation-program/documents/security-policies/140sp5077.pdf :

    > The Qualcomm Crypto Engine Core does not support any non-invasive
    > security techniques. Therefore, this section is not applicable.
    [...]
    > The Qualcomm Crypto Engine Core does not implement security
    > mechanisms to mitigate other attacks.

- Eric