1// SPDX-License-Identifier: GPL-2.0 OR MIT
2/*
3 * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
4 *
5 * This is an implementation of the BLAKE2s hash and PRF functions.
6 *
7 * Information: https://blake2.net/
8 *
9 */
10
11#include <crypto/internal/blake2s.h>
12#include <linux/types.h>
13#include <linux/string.h>
14#include <linux/kernel.h>
15#include <linux/module.h>
16#include <linux/init.h>
17#include <linux/bug.h>
18
19static inline void blake2s_set_lastblock(struct blake2s_state *state)
20{
21	state->f[0] = -1;
22}
23
24void blake2s_update(struct blake2s_state *state, const u8 *in, size_t inlen)
25{
26	const size_t fill = BLAKE2S_BLOCK_SIZE - state->buflen;
27
28	if (unlikely(!inlen))
29		return;
30	if (inlen > fill) {
31		memcpy(state->buf + state->buflen, in, fill);
32		blake2s_compress(state, state->buf, 1, BLAKE2S_BLOCK_SIZE);
33		state->buflen = 0;
34		in += fill;
35		inlen -= fill;
36	}
37	if (inlen > BLAKE2S_BLOCK_SIZE) {
38		const size_t nblocks = DIV_ROUND_UP(inlen, BLAKE2S_BLOCK_SIZE);
39		blake2s_compress(state, in, nblocks - 1, BLAKE2S_BLOCK_SIZE);
40		in += BLAKE2S_BLOCK_SIZE * (nblocks - 1);
41		inlen -= BLAKE2S_BLOCK_SIZE * (nblocks - 1);
42	}
43	memcpy(state->buf + state->buflen, in, inlen);
44	state->buflen += inlen;
45}
46EXPORT_SYMBOL(blake2s_update);
47
48void blake2s_final(struct blake2s_state *state, u8 *out)
49{
50	WARN_ON(IS_ENABLED(DEBUG) && !out);
51	blake2s_set_lastblock(state);
52	memset(state->buf + state->buflen, 0,
53	       BLAKE2S_BLOCK_SIZE - state->buflen); /* Padding */
54	blake2s_compress(state, state->buf, 1, state->buflen);
55	cpu_to_le32_array(state->h, ARRAY_SIZE(state->h));
56	memcpy(out, state->h, state->outlen);
57	memzero_explicit(state, sizeof(*state));
58}
59EXPORT_SYMBOL(blake2s_final);
60
61static int __init blake2s_mod_init(void)
62{
63	if (!IS_ENABLED(CONFIG_CRYPTO_MANAGER_DISABLE_TESTS) &&
64	    WARN_ON(!blake2s_selftest()))
65		return -ENODEV;
66	return 0;
67}
68
69module_init(blake2s_mod_init);
70MODULE_DESCRIPTION("BLAKE2s hash function");
71MODULE_AUTHOR("Jason A. Donenfeld <Jason@zx2c4.com>");
72