linux/lib/crypto/blake2s.c
Jason A. Donenfeld 66d7fb94e4 crypto: blake2s - generic C library implementation and selftest
The C implementation was originally based on Samuel Neves' public
domain reference implementation but has since been heavily modified
for the kernel. We're able to do compile-time optimizations by moving
some scaffolding around the final function into the header file.

Information: https://blake2.net/

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Samuel Neves <sneves@dei.uc.pt>
Co-developed-by: Samuel Neves <sneves@dei.uc.pt>
[ardb: - move from lib/zinc to lib/crypto
       - remove simd handling
       - rewrote selftest for better coverage
       - use fixed digest length for blake2s_hmac() and rename to
         blake2s256_hmac() ]
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-11-17 09:02:42 +08:00

126 lines
3.6 KiB
C

// SPDX-License-Identifier: GPL-2.0 OR MIT
/*
* Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
*
* This is an implementation of the BLAKE2s hash and PRF functions.
*
* Information: https://blake2.net/
*
*/
#include <crypto/internal/blake2s.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/bug.h>
#include <asm/unaligned.h>
bool blake2s_selftest(void);
void blake2s_update(struct blake2s_state *state, const u8 *in, size_t inlen)
{
const size_t fill = BLAKE2S_BLOCK_SIZE - state->buflen;
if (unlikely(!inlen))
return;
if (inlen > fill) {
memcpy(state->buf + state->buflen, in, fill);
if (IS_ENABLED(CONFIG_CRYPTO_ARCH_HAVE_LIB_BLAKE2S))
blake2s_compress_arch(state, state->buf, 1,
BLAKE2S_BLOCK_SIZE);
else
blake2s_compress_generic(state, state->buf, 1,
BLAKE2S_BLOCK_SIZE);
state->buflen = 0;
in += fill;
inlen -= fill;
}
if (inlen > BLAKE2S_BLOCK_SIZE) {
const size_t nblocks = DIV_ROUND_UP(inlen, BLAKE2S_BLOCK_SIZE);
/* Hash one less (full) block than strictly possible */
if (IS_ENABLED(CONFIG_CRYPTO_ARCH_HAVE_LIB_BLAKE2S))
blake2s_compress_arch(state, in, nblocks - 1,
BLAKE2S_BLOCK_SIZE);
else
blake2s_compress_generic(state, in, nblocks - 1,
BLAKE2S_BLOCK_SIZE);
in += BLAKE2S_BLOCK_SIZE * (nblocks - 1);
inlen -= BLAKE2S_BLOCK_SIZE * (nblocks - 1);
}
memcpy(state->buf + state->buflen, in, inlen);
state->buflen += inlen;
}
EXPORT_SYMBOL(blake2s_update);
void blake2s_final(struct blake2s_state *state, u8 *out)
{
WARN_ON(IS_ENABLED(DEBUG) && !out);
blake2s_set_lastblock(state);
memset(state->buf + state->buflen, 0,
BLAKE2S_BLOCK_SIZE - state->buflen); /* Padding */
if (IS_ENABLED(CONFIG_CRYPTO_ARCH_HAVE_LIB_BLAKE2S))
blake2s_compress_arch(state, state->buf, 1, state->buflen);
else
blake2s_compress_generic(state, state->buf, 1, state->buflen);
cpu_to_le32_array(state->h, ARRAY_SIZE(state->h));
memcpy(out, state->h, state->outlen);
memzero_explicit(state, sizeof(*state));
}
EXPORT_SYMBOL(blake2s_final);
void blake2s256_hmac(u8 *out, const u8 *in, const u8 *key, const size_t inlen,
const size_t keylen)
{
struct blake2s_state state;
u8 x_key[BLAKE2S_BLOCK_SIZE] __aligned(__alignof__(u32)) = { 0 };
u8 i_hash[BLAKE2S_HASH_SIZE] __aligned(__alignof__(u32));
int i;
if (keylen > BLAKE2S_BLOCK_SIZE) {
blake2s_init(&state, BLAKE2S_HASH_SIZE);
blake2s_update(&state, key, keylen);
blake2s_final(&state, x_key);
} else
memcpy(x_key, key, keylen);
for (i = 0; i < BLAKE2S_BLOCK_SIZE; ++i)
x_key[i] ^= 0x36;
blake2s_init(&state, BLAKE2S_HASH_SIZE);
blake2s_update(&state, x_key, BLAKE2S_BLOCK_SIZE);
blake2s_update(&state, in, inlen);
blake2s_final(&state, i_hash);
for (i = 0; i < BLAKE2S_BLOCK_SIZE; ++i)
x_key[i] ^= 0x5c ^ 0x36;
blake2s_init(&state, BLAKE2S_HASH_SIZE);
blake2s_update(&state, x_key, BLAKE2S_BLOCK_SIZE);
blake2s_update(&state, i_hash, BLAKE2S_HASH_SIZE);
blake2s_final(&state, i_hash);
memcpy(out, i_hash, BLAKE2S_HASH_SIZE);
memzero_explicit(x_key, BLAKE2S_BLOCK_SIZE);
memzero_explicit(i_hash, BLAKE2S_HASH_SIZE);
}
EXPORT_SYMBOL(blake2s256_hmac);
static int __init mod_init(void)
{
if (!IS_ENABLED(CONFIG_CRYPTO_MANAGER_DISABLE_TESTS) &&
WARN_ON(!blake2s_selftest()))
return -ENODEV;
return 0;
}
static void __exit mod_exit(void)
{
}
module_init(mod_init);
module_exit(mod_exit);
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("BLAKE2s hash function");
MODULE_AUTHOR("Jason A. Donenfeld <Jason@zx2c4.com>");