Re: [PATCH 02/15] crypto: lib/poly1305 - Add block-only interface

[Eric Biggers <ebiggers@kernel.org>]

On Fri, Apr 25, 2025 at 07:49:42PM +0800, Herbert Xu wrote:
> On Thu, Apr 24, 2025 at 09:14:31AM -0700, Eric Biggers wrote:
> > 
> > Use 'raw_key' instead of 'key' when referring to the 16-byte polynomial hash key
> > which is the first half of the full 32-byte Poly1305 one-time key.
> 
> OK I'll change that.
> 
> > > +	desc->buflen = BLOCK_HASH_UPDATE(&poly1305_block, &desc->state,
> > > +					 src, nbytes, POLY1305_BLOCK_SIZE,
> > > +					 desc->buf, desc->buflen);
> > >  }
> > >  EXPORT_SYMBOL_GPL(poly1305_update_generic);
> > 
> > Again, should just write this out without the weird macro, which is also being
> > used incorrectly here.
> 
> If you have a better way of abstracting out the partial block
> handling, please let me know.

It doesn't seem to be worth abstracting out further.  Especially with the slight
variations in different algorithms and APIs which are hard to handle correctly
in a shared macro.

> As to using it incorrectly, could you please be more specific?

You're assigning desc->buflen to itself.  Which presumably you missed since the
macro obfuscates what is going on.

- Eric