Re: [PATCH v4 1/5] crypto: add blake2b generic implementation

[Eric Biggers <ebiggers@kernel.org>]

On Fri, Oct 11, 2019 at 06:52:04PM +0200, David Sterba wrote:
> diff --git a/crypto/Makefile b/crypto/Makefile
> index 9479e1a45d8c..2318420d3e71 100644
> --- a/crypto/Makefile
> +++ b/crypto/Makefile
> @@ -74,6 +74,7 @@ obj-$(CONFIG_CRYPTO_STREEBOG) += streebog_generic.o
>  obj-$(CONFIG_CRYPTO_WP512) += wp512.o
>  CFLAGS_wp512.o := $(call cc-option,-fno-schedule-insns)  # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79149
>  obj-$(CONFIG_CRYPTO_TGR192) += tgr192.o
> +obj-$(CONFIG_CRYPTO_BLAKE2B) += blake2b_generic.o
>  obj-$(CONFIG_CRYPTO_GF128MUL) += gf128mul.o
>  obj-$(CONFIG_CRYPTO_ECB) += ecb.o
>  obj-$(CONFIG_CRYPTO_CBC) += cbc.o
> diff --git a/crypto/blake2b_generic.c b/crypto/blake2b_generic.c
> new file mode 100644
> index 000000000000..e31fb669383b
> --- /dev/null
> +++ b/crypto/blake2b_generic.c
> @@ -0,0 +1,418 @@
> +// SPDX-License-Identifier: (GPL-2.0-only OR Apache-2.0)
> +/*
> + * BLAKE2b reference source code package - reference C implementations
> + *
> + * Copyright 2012, Samuel Neves <sneves@dei.uc.pt>.  You may use this under the
> + * terms of the CC0, the OpenSSL Licence, or the Apache Public License 2.0, at
> + * your option.  The terms of these licenses can be found at:
> + *
> + * - CC0 1.0 Universal : http://creativecommons.org/publicdomain/zero/1.0
> + * - OpenSSL license   : https://www.openssl.org/source/license.html
> + * - Apache 2.0        : http://www.apache.org/licenses/LICENSE-2.0
> + *
> + * More information about the BLAKE2 hash function can be found at
> + * https://blake2.net.
> + */
> +
> +#include <asm/unaligned.h>
> +#include <linux/module.h>
> +#include <linux/string.h>
> +#include <linux/kernel.h>
> +#include <linux/bitops.h>
> +#include <crypto/internal/hash.h>
> +#include <crypto/blake2b.h>
> +
> +struct blake2b_param
> +{

It should be 'struct blake2b_param {'

checkpatch.pl should warn about this.  Can you fix the checkpatch warnings that
make sense to fix?

> +/* init xors IV with input parameter block */
> +static int blake2b_init_param(struct blake2b_state *S,
> +			      const struct blake2b_param *P)
> +{
> +	const u8 *p = (const u8 *)(P);
> +	size_t i;
> +
> +	blake2b_init0(S);
> +
> +	/* IV XOR ParamBlock */
> +	for (i = 0; i < 8; ++i)
> +		S->h[i] ^= get_unaligned_le64(p + sizeof(S->h[i]) * i);
> +
> +	S->outlen = P->digest_length;
> +	return 0;
> +}

No need for this to have a return value anymore.  Same with:

	blake2b_init_param()
	blake2b_update()
	blake2b_init()
	blake2b_init_key()
	blake2b_final()

The code would be more readable if they returned void, since otherwise it gives
the impression that errors can occur.

> +static int blake2b_update(struct blake2b_state *S, const void *pin, size_t inlen)
> +{
> +	const unsigned char *in = (const unsigned char *)pin;

Convention is to use 'u8', not 'unsigned char'.

> +MODULE_ALIAS_CRYPTO("blake2b");
> +MODULE_ALIAS_CRYPTO("blake2b-generic");

Should remove these module aliases now that the "blake2b" algorithm was removed.

- Eric