Re: [PATCH] crypto: akcipher - default implementations for setting private/public keys

[Herbert Xu]

On Tue, Aug 30, 2022 at 11:48:23AM +0100, Ignat Korchagin wrote:
>
> I vaguely remember some initial research in quantum-resistant
> signatures, which used HMAC for "signing" thus don't have any public
> keys. But it is way beyond my expertise to comment on the practicality
> and availability of such schemes.

We could always add this again should an algorithm requiring
it be introduced.

> I'm more concerned here about a buggy "third-party" RSA driver, which
> may not implement the callback and which gets prioritised by the
> framework, thus giving the ability to trigger a NULL-ptr dereference
> from userspace via keyctl(2). I think the Crypto API framework should
> be a bit more robust to handle such a case, but I also understand that
> there are a lot of "if"s in this scenario and we can say it is up to
> crypto driver not to be buggy. Therefore, consider my opinion as not
> strong and I can post a v2, which does not provide a default stub for
> set_pub_key, if you prefer.

If you're concerned with buggy algorithms/drivers, we should
ensure that the self-tests catch this.

Cheers,
-- 
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt