xref: /openbmc/linux/lib/crypto/blake2s.c (revision f21e49be)
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 #if IS_ENABLED(CONFIG_CRYPTO_ARCH_HAVE_LIB_BLAKE2S)
20 #  define blake2s_compress blake2s_compress_arch
21 #else
22 #  define blake2s_compress blake2s_compress_generic
23 #endif
24 
25 void blake2s_update(struct blake2s_state *state, const u8 *in, size_t inlen)
26 {
27 	__blake2s_update(state, in, inlen, blake2s_compress);
28 }
29 EXPORT_SYMBOL(blake2s_update);
30 
31 void blake2s_final(struct blake2s_state *state, u8 *out)
32 {
33 	WARN_ON(IS_ENABLED(DEBUG) && !out);
34 	__blake2s_final(state, out, blake2s_compress);
35 	memzero_explicit(state, sizeof(*state));
36 }
37 EXPORT_SYMBOL(blake2s_final);
38 
39 void blake2s256_hmac(u8 *out, const u8 *in, const u8 *key, const size_t inlen,
40 		     const size_t keylen)
41 {
42 	struct blake2s_state state;
43 	u8 x_key[BLAKE2S_BLOCK_SIZE] __aligned(__alignof__(u32)) = { 0 };
44 	u8 i_hash[BLAKE2S_HASH_SIZE] __aligned(__alignof__(u32));
45 	int i;
46 
47 	if (keylen > BLAKE2S_BLOCK_SIZE) {
48 		blake2s_init(&state, BLAKE2S_HASH_SIZE);
49 		blake2s_update(&state, key, keylen);
50 		blake2s_final(&state, x_key);
51 	} else
52 		memcpy(x_key, key, keylen);
53 
54 	for (i = 0; i < BLAKE2S_BLOCK_SIZE; ++i)
55 		x_key[i] ^= 0x36;
56 
57 	blake2s_init(&state, BLAKE2S_HASH_SIZE);
58 	blake2s_update(&state, x_key, BLAKE2S_BLOCK_SIZE);
59 	blake2s_update(&state, in, inlen);
60 	blake2s_final(&state, i_hash);
61 
62 	for (i = 0; i < BLAKE2S_BLOCK_SIZE; ++i)
63 		x_key[i] ^= 0x5c ^ 0x36;
64 
65 	blake2s_init(&state, BLAKE2S_HASH_SIZE);
66 	blake2s_update(&state, x_key, BLAKE2S_BLOCK_SIZE);
67 	blake2s_update(&state, i_hash, BLAKE2S_HASH_SIZE);
68 	blake2s_final(&state, i_hash);
69 
70 	memcpy(out, i_hash, BLAKE2S_HASH_SIZE);
71 	memzero_explicit(x_key, BLAKE2S_BLOCK_SIZE);
72 	memzero_explicit(i_hash, BLAKE2S_HASH_SIZE);
73 }
74 EXPORT_SYMBOL(blake2s256_hmac);
75 
76 static int __init blake2s_mod_init(void)
77 {
78 	if (!IS_ENABLED(CONFIG_CRYPTO_MANAGER_DISABLE_TESTS) &&
79 	    WARN_ON(!blake2s_selftest()))
80 		return -ENODEV;
81 	return 0;
82 }
83 
84 static void __exit blake2s_mod_exit(void)
85 {
86 }
87 
88 module_init(blake2s_mod_init);
89 module_exit(blake2s_mod_exit);
90 MODULE_LICENSE("GPL v2");
91 MODULE_DESCRIPTION("BLAKE2s hash function");
92 MODULE_AUTHOR("Jason A. Donenfeld <Jason@zx2c4.com>");
93