xref: /linux/lib/crypto/blake2s.c (revision 13150742b09e720fdf021de14cd2b98b37415a89)
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/bug.h>
13 #include <linux/export.h>
14 #include <linux/init.h>
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/string.h>
18 #include <linux/types.h>
19 
blake2s_set_lastblock(struct blake2s_state * state)20 static inline void blake2s_set_lastblock(struct blake2s_state *state)
21 {
22 	state->f[0] = -1;
23 }
24 
blake2s_update(struct blake2s_state * state,const u8 * in,size_t inlen)25 void blake2s_update(struct blake2s_state *state, const u8 *in, size_t inlen)
26 {
27 	const size_t fill = BLAKE2S_BLOCK_SIZE - state->buflen;
28 
29 	if (unlikely(!inlen))
30 		return;
31 	if (inlen > fill) {
32 		memcpy(state->buf + state->buflen, in, fill);
33 		blake2s_compress(state, state->buf, 1, BLAKE2S_BLOCK_SIZE);
34 		state->buflen = 0;
35 		in += fill;
36 		inlen -= fill;
37 	}
38 	if (inlen > BLAKE2S_BLOCK_SIZE) {
39 		const size_t nblocks = DIV_ROUND_UP(inlen, BLAKE2S_BLOCK_SIZE);
40 		blake2s_compress(state, in, nblocks - 1, BLAKE2S_BLOCK_SIZE);
41 		in += BLAKE2S_BLOCK_SIZE * (nblocks - 1);
42 		inlen -= BLAKE2S_BLOCK_SIZE * (nblocks - 1);
43 	}
44 	memcpy(state->buf + state->buflen, in, inlen);
45 	state->buflen += inlen;
46 }
47 EXPORT_SYMBOL(blake2s_update);
48 
blake2s_final(struct blake2s_state * state,u8 * out)49 void blake2s_final(struct blake2s_state *state, u8 *out)
50 {
51 	WARN_ON(IS_ENABLED(DEBUG) && !out);
52 	blake2s_set_lastblock(state);
53 	memset(state->buf + state->buflen, 0,
54 	       BLAKE2S_BLOCK_SIZE - state->buflen); /* Padding */
55 	blake2s_compress(state, state->buf, 1, state->buflen);
56 	cpu_to_le32_array(state->h, ARRAY_SIZE(state->h));
57 	memcpy(out, state->h, state->outlen);
58 	memzero_explicit(state, sizeof(*state));
59 }
60 EXPORT_SYMBOL(blake2s_final);
61 
blake2s_mod_init(void)62 static int __init blake2s_mod_init(void)
63 {
64 	if (IS_ENABLED(CONFIG_CRYPTO_SELFTESTS) &&
65 	    WARN_ON(!blake2s_selftest()))
66 		return -ENODEV;
67 	return 0;
68 }
69 
70 module_init(blake2s_mod_init);
71 MODULE_DESCRIPTION("BLAKE2s hash function");
72 MODULE_AUTHOR("Jason A. Donenfeld <Jason@zx2c4.com>");
73