Re: Where to add FIPS tests

[Eric Biggers]

On Mon, Nov 17, 2025 at 04:01:39PM +0000, David Howells wrote:
> Hi Herbert,
> 
> I'm wondering from where I should invoke the FIPS tests for ML-DSA.
> 
> Currently, the asymmetric key type has some FIPS selftests for RSA and ECDSA
> built into it, but I wonder if that's the best way.  The problem is that it
> does the selftest during module init - but that can only test whatever
> algorithms are built into the base kernel image and initialised at the time
> late_initcall() happens.
> 
> It might be better to put the tests into the algorithm modules themselves -
> but that then has a potential circular dependency issue.  However, that might
> not matter as the asymmetric key type won't be built as a module and will be
> built into the kernel (though some of the components such as X.509 and PKCS#7
> can be built as modules).
> 
> If I don't involve X.509/PKCS#7 in the selftest, then doing it from the ML-DSA
> modules during module init would be fine.
> 
> Do you (or anyone else) have any thoughts?

The FIPS self-test should just go in the algorithm module itself and
test ML-DSA directly.  See the other lib/crypto/ FIPS self-tests.
Please check the FIPS Implementation Guidance documentation to see what
is needed; it isn't actually very much.

- Eric