xref: /openbmc/linux/lib/crypto/blake2s.c (revision 34fa67e7)
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 
19 void blake2s_update(struct blake2s_state *state, const u8 *in, size_t inlen)
20 {
21 	__blake2s_update(state, in, inlen, blake2s_compress);
22 }
23 EXPORT_SYMBOL(blake2s_update);
24 
25 void blake2s_final(struct blake2s_state *state, u8 *out)
26 {
27 	WARN_ON(IS_ENABLED(DEBUG) && !out);
28 	__blake2s_final(state, out, blake2s_compress);
29 	memzero_explicit(state, sizeof(*state));
30 }
31 EXPORT_SYMBOL(blake2s_final);
32 
33 void blake2s256_hmac(u8 *out, const u8 *in, const u8 *key, const size_t inlen,
34 		     const size_t keylen)
35 {
36 	struct blake2s_state state;
37 	u8 x_key[BLAKE2S_BLOCK_SIZE] __aligned(__alignof__(u32)) = { 0 };
38 	u8 i_hash[BLAKE2S_HASH_SIZE] __aligned(__alignof__(u32));
39 	int i;
40 
41 	if (keylen > BLAKE2S_BLOCK_SIZE) {
42 		blake2s_init(&state, BLAKE2S_HASH_SIZE);
43 		blake2s_update(&state, key, keylen);
44 		blake2s_final(&state, x_key);
45 	} else
46 		memcpy(x_key, key, keylen);
47 
48 	for (i = 0; i < BLAKE2S_BLOCK_SIZE; ++i)
49 		x_key[i] ^= 0x36;
50 
51 	blake2s_init(&state, BLAKE2S_HASH_SIZE);
52 	blake2s_update(&state, x_key, BLAKE2S_BLOCK_SIZE);
53 	blake2s_update(&state, in, inlen);
54 	blake2s_final(&state, i_hash);
55 
56 	for (i = 0; i < BLAKE2S_BLOCK_SIZE; ++i)
57 		x_key[i] ^= 0x5c ^ 0x36;
58 
59 	blake2s_init(&state, BLAKE2S_HASH_SIZE);
60 	blake2s_update(&state, x_key, BLAKE2S_BLOCK_SIZE);
61 	blake2s_update(&state, i_hash, BLAKE2S_HASH_SIZE);
62 	blake2s_final(&state, i_hash);
63 
64 	memcpy(out, i_hash, BLAKE2S_HASH_SIZE);
65 	memzero_explicit(x_key, BLAKE2S_BLOCK_SIZE);
66 	memzero_explicit(i_hash, BLAKE2S_HASH_SIZE);
67 }
68 EXPORT_SYMBOL(blake2s256_hmac);
69 
70 static int __init blake2s_mod_init(void)
71 {
72 	if (!IS_ENABLED(CONFIG_CRYPTO_MANAGER_DISABLE_TESTS) &&
73 	    WARN_ON(!blake2s_selftest()))
74 		return -ENODEV;
75 	return 0;
76 }
77 
78 static void __exit blake2s_mod_exit(void)
79 {
80 }
81 
82 module_init(blake2s_mod_init);
83 module_exit(blake2s_mod_exit);
84 MODULE_LICENSE("GPL v2");
85 MODULE_DESCRIPTION("BLAKE2s hash function");
86 MODULE_AUTHOR("Jason A. Donenfeld <Jason@zx2c4.com>");
87