Re: [PATCH 09/15] crypto: lib/poly1305 - Use block-only interface

[Eric Biggers <ebiggers@kernel.org>]

On Thu, Apr 24, 2025 at 08:48:01AM -0700, Eric Biggers wrote:
> On Thu, Apr 24, 2025 at 06:47:16PM +0800, Herbert Xu wrote:
> > diff --git a/lib/crypto/poly1305.c b/lib/crypto/poly1305.c
> > index ebdfccf378ee..a37b424ee84b 100644
> > --- a/lib/crypto/poly1305.c
> > +++ b/lib/crypto/poly1305.c
> > @@ -22,47 +22,59 @@ void poly1305_block_init_generic(struct poly1305_block_state *desc,
> >  }
> >  EXPORT_SYMBOL_GPL(poly1305_block_init_generic);
> >  
> > -void poly1305_init_generic(struct poly1305_desc_ctx *desc,
> > -			   const u8 key[POLY1305_KEY_SIZE])
> > +void poly1305_init(struct poly1305_desc_ctx *desc,
> > +		   const u8 key[POLY1305_KEY_SIZE])
> >  {
> >  	desc->s[0] = get_unaligned_le32(key + 16);
> >  	desc->s[1] = get_unaligned_le32(key + 20);
> >  	desc->s[2] = get_unaligned_le32(key + 24);
> >  	desc->s[3] = get_unaligned_le32(key + 28);
> >  	desc->buflen = 0;
> > -	poly1305_block_init_generic(&desc->state, key);
> > +	if (IS_ENABLED(CONFIG_CRYPTO_ARCH_HAVE_LIB_POLY1305))
> > +		poly1305_block_init_arch(&desc->state, key);
> > +	else
> > +		poly1305_block_init_generic(&desc->state, key);
> >  }
> > -EXPORT_SYMBOL_GPL(poly1305_init_generic);
> > +EXPORT_SYMBOL(poly1305_init);
> >  
> > -static inline void poly1305_block(struct poly1305_block_state *state, const u8 *src,
> > -				  unsigned int len)
> > +static inline void poly1305_block(struct poly1305_block_state *state,
> > +				  const u8 *src, unsigned int len)
> >  {
> > -	poly1305_blocks_generic(state, src, len, 1);
> > +	if (!IS_ENABLED(CONFIG_CRYPTO_ARCH_HAVE_LIB_POLY1305))
> > +		poly1305_blocks_generic(state, src, len, 1);
> > +	poly1305_blocks_arch(state, src, len, 1);
> >  }
> >  
> > -void poly1305_update_generic(struct poly1305_desc_ctx *desc, const u8 *src,
> > -			     unsigned int nbytes)
> > +void poly1305_update(struct poly1305_desc_ctx *desc,
> > +		     const u8 *src, unsigned int nbytes)
> >  {
> >  	desc->buflen = BLOCK_HASH_UPDATE(&poly1305_block, &desc->state,
> >  					 src, nbytes, POLY1305_BLOCK_SIZE,
> >  					 desc->buf, desc->buflen);
> >  }
> > -EXPORT_SYMBOL_GPL(poly1305_update_generic);
> > +EXPORT_SYMBOL(poly1305_update);
> 
> This randomly changes it to only do 1 block at a time.
> 
> And it also changes it to call poly1305_blocks_arch() even if the arch doesn't
> have it, causing build errors.

Actually maybe it still does more than 1 block at a time, since the '1' is
actually the padbit argument, and maybe poly1305_block() is missing an "s"
accidentally.  Hard to tell because the code is obfuscated in the macro though.

- Eric