Re: [RFC PATCH 2/8] crypto/krb5: Provide Kerberos 5 crypto through AEAD API

David Howells
2025-01-10T10:26:52Z

Herbert Xu <herbert@gondor.apana.org.au> wrote:

> rfc8009 is basically the same as authenc. So rather than being an
> AEAD algorithm it should really be an AEAD template which takes a
> cipher and and a hash as its parameters.

That's only half true. If it's acting in checksum mode then it's not an
authenc() algo.

> In fact, you could probably use authenc directly.

However the point of having a library is to abstract those details from the
callers. You wanted me to rewrite the library as AEAD algorithms, which I
have done as far as I can. This makes the object for each kerberos enctype
look the same from the PoV of the clients.

I have plans to make the kerberos AEAD use an authenc behind the scenes rather
than a cipher plus hash where appropriate as a future evolution, but the
optimised authenc drivers (QAT for example) that I can find don't appear to
support CTS.

So I'm not sure what it is you were envisioning.

David