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, block: state->buf, nblocks: 1, inc: 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, block: in, nblocks: nblocks - 1, inc: 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, block: state->buf, nblocks: 1, inc: state->buflen);
55 cpu_to_le32_array(buf: state->h, ARRAY_SIZE(state->h));
56 memcpy(out, state->h, state->outlen);
57 memzero_explicit(s: state, count: 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

source code of linux/lib/crypto/blake2s.c