Missing input validation checks in ml-kem

[FinnRG]

FIPS 203 defines two input validations which are currently not done in ml-kem:

1. The modulus check for encapsulate (section 7.2)
2. The hash check for decapsulate (section 7.3)

I haven't checked the key loading functions from section 7.1 yet.

Is there a specific technical reason or API design reason why these checks are omitted? The spec mentions that these checks can be acquired through other means, but according to NIST 800-227 these mostly boil down to trusted sources.

If there is no technical/other reason for omitting these checks I would be happy to contribute them/

[tarcieri]

1. sounds like a dup of ml-kem: validate encryption/encapsulation keys #179
2. sounds like a dup of ML-KEM: Validate expanded decapsulation key hash #207

[FinnRG]

@tarcieri Yes, I was checking my local 0.2.3 source instead of the 0.3 rc here on GitHub, sorry for the noise.

Is there a timeline for the 0.3 release?

[tarcieri]

Main thing needed is a stable release of pkcs8 which is blocked on a number of (transitive) dependencies, but hopefully in a month or so