Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
lib/crypto: blake2b: Add BLAKE2b library functions
Add a library API for BLAKE2b, closely modeled after the BLAKE2s API.
This will allow in-kernel users such as btrfs to use BLAKE2b without
going through the generic crypto layer. In addition, as usual the
BLAKE2b crypto_shash algorithms will be reimplemented on top of this.
Note: to create lib/crypto/blake2b.c I made a copy of
lib/crypto/blake2s.c and made the updates from BLAKE2s => BLAKE2b. This
way, the BLAKE2s and BLAKE2b code is kept consistent. Therefore, it
borrows the SPDX-License-Identifier and Copyright from
lib/crypto/blake2s.c rather than crypto/blake2b_generic.c.
The library API uses 'struct blake2b_ctx', consistent with other
lib/crypto/ APIs. The existing 'struct blake2b_state' will be removed
once the blake2b crypto_shash algorithms are updated to stop using it.
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20251018043106.375964-7-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
+330
-13
+121
-12
include/crypto/blake2b.h
+121
-12
include/crypto/blake2b.h
···
28
28
BLAKE2B_512_HASH_SIZE = 64,
29
29
};
30
30
31
+
/**
32
+
* struct blake2b_ctx - Context for hashing a message with BLAKE2b
33
+
* @h: compression function state
34
+
* @t: block counter
35
+
* @f: finalization indicator
36
+
* @buf: partial block buffer; 'buflen' bytes are valid
37
+
* @buflen: number of bytes buffered in @buf
38
+
* @outlen: length of output hash value in bytes, at most BLAKE2B_HASH_SIZE
39
+
*/
40
+
struct blake2b_ctx {
41
+
/* 'h', 't', and 'f' are used in assembly code, so keep them as-is. */
42
+
u64 h[8];
43
+
u64 t[2];
44
+
u64 f[2];
45
+
u8 buf[BLAKE2B_BLOCK_SIZE];
46
+
unsigned int buflen;
47
+
unsigned int outlen;
48
+
};
49
+
31
50
enum blake2b_iv {
32
51
BLAKE2B_IV0 = 0x6A09E667F3BCC908ULL,
33
52
BLAKE2B_IV1 = 0xBB67AE8584CAA73BULL,
···
58
39
BLAKE2B_IV7 = 0x5BE0CD19137E2179ULL,
59
40
};
60
41
61
-
static inline void __blake2b_init(struct blake2b_state *state, size_t outlen,
62
-
size_t keylen)
42
+
static inline void __blake2b_init(struct blake2b_ctx *ctx, size_t outlen,
43
+
const void *key, size_t keylen)
63
44
{
64
-
state->h[0] = BLAKE2B_IV0 ^ (0x01010000 | keylen << 8 | outlen);
65
-
state->h[1] = BLAKE2B_IV1;
66
-
state->h[2] = BLAKE2B_IV2;
67
-
state->h[3] = BLAKE2B_IV3;
68
-
state->h[4] = BLAKE2B_IV4;
69
-
state->h[5] = BLAKE2B_IV5;
70
-
state->h[6] = BLAKE2B_IV6;
71
-
state->h[7] = BLAKE2B_IV7;
72
-
state->t[0] = 0;
73
-
state->t[1] = 0;
45
+
ctx->h[0] = BLAKE2B_IV0 ^ (0x01010000 | keylen << 8 | outlen);
46
+
ctx->h[1] = BLAKE2B_IV1;
47
+
ctx->h[2] = BLAKE2B_IV2;
48
+
ctx->h[3] = BLAKE2B_IV3;
49
+
ctx->h[4] = BLAKE2B_IV4;
50
+
ctx->h[5] = BLAKE2B_IV5;
51
+
ctx->h[6] = BLAKE2B_IV6;
52
+
ctx->h[7] = BLAKE2B_IV7;
53
+
ctx->t[0] = 0;
54
+
ctx->t[1] = 0;
55
+
ctx->f[0] = 0;
56
+
ctx->f[1] = 0;
57
+
ctx->buflen = 0;
58
+
ctx->outlen = outlen;
59
+
if (keylen) {
60
+
memcpy(ctx->buf, key, keylen);
61
+
memset(&ctx->buf[keylen], 0, BLAKE2B_BLOCK_SIZE - keylen);
62
+
ctx->buflen = BLAKE2B_BLOCK_SIZE;
63
+
}
64
+
}
65
+
66
+
/**
67
+
* blake2b_init() - Initialize a BLAKE2b context for a new message (unkeyed)
68
+
* @ctx: the context to initialize
69
+
* @outlen: length of output hash value in bytes, at most BLAKE2B_HASH_SIZE
70
+
*
71
+
* Context: Any context.
72
+
*/
73
+
static inline void blake2b_init(struct blake2b_ctx *ctx, size_t outlen)
74
+
{
75
+
__blake2b_init(ctx, outlen, NULL, 0);
76
+
}
77
+
78
+
/**
79
+
* blake2b_init_key() - Initialize a BLAKE2b context for a new message (keyed)
80
+
* @ctx: the context to initialize
81
+
* @outlen: length of output hash value in bytes, at most BLAKE2B_HASH_SIZE
82
+
* @key: the key
83
+
* @keylen: the key length in bytes, at most BLAKE2B_KEY_SIZE
84
+
*
85
+
* Context: Any context.
86
+
*/
87
+
static inline void blake2b_init_key(struct blake2b_ctx *ctx, size_t outlen,
88
+
const void *key, size_t keylen)
89
+
{
90
+
WARN_ON(IS_ENABLED(DEBUG) && (!outlen || outlen > BLAKE2B_HASH_SIZE ||
91
+
!key || !keylen || keylen > BLAKE2B_KEY_SIZE));
92
+
93
+
__blake2b_init(ctx, outlen, key, keylen);
94
+
}
95
+
96
+
/**
97
+
* blake2b_update() - Update a BLAKE2b context with message data
98
+
* @ctx: the context to update; must have been initialized
99
+
* @in: the message data
100
+
* @inlen: the data length in bytes
101
+
*
102
+
* This can be called any number of times.
103
+
*
104
+
* Context: Any context.
105
+
*/
106
+
void blake2b_update(struct blake2b_ctx *ctx, const u8 *in, size_t inlen);
107
+
108
+
/**
109
+
* blake2b_final() - Finish computing a BLAKE2b hash
110
+
* @ctx: the context to finalize; must have been initialized
111
+
* @out: (output) the resulting BLAKE2b hash. Its length will be equal to the
112
+
* @outlen that was passed to blake2b_init() or blake2b_init_key().
113
+
*
114
+
* After finishing, this zeroizes @ctx. So the caller does not need to do it.
115
+
*
116
+
* Context: Any context.
117
+
*/
118
+
void blake2b_final(struct blake2b_ctx *ctx, u8 *out);
119
+
120
+
/**
121
+
* blake2b() - Compute BLAKE2b hash in one shot
122
+
* @key: the key, or NULL for an unkeyed hash
123
+
* @keylen: the key length in bytes (at most BLAKE2B_KEY_SIZE), or 0 for an
124
+
* unkeyed hash
125
+
* @in: the message data
126
+
* @inlen: the data length in bytes
127
+
* @out: (output) the resulting BLAKE2b hash, with length @outlen
128
+
* @outlen: length of output hash value in bytes, at most BLAKE2B_HASH_SIZE
129
+
*
130
+
* Context: Any context.
131
+
*/
132
+
static inline void blake2b(const u8 *key, size_t keylen,
133
+
const u8 *in, size_t inlen,
134
+
u8 *out, size_t outlen)
135
+
{
136
+
struct blake2b_ctx ctx;
137
+
138
+
WARN_ON(IS_ENABLED(DEBUG) && ((!in && inlen > 0) || !out || !outlen ||
139
+
outlen > BLAKE2B_HASH_SIZE || keylen > BLAKE2B_KEY_SIZE ||
140
+
(!key && keylen)));
141
+
142
+
__blake2b_init(&ctx, outlen, key, keylen);
143
+
blake2b_update(&ctx, in, inlen);
144
+
blake2b_final(&ctx, out);
74
145
}
75
146
76
147
#endif /* _CRYPTO_BLAKE2B_H */
+16
-1
include/crypto/internal/blake2b.h
+16
-1
include/crypto/internal/blake2b.h
···
57
57
return 0;
58
58
}
59
59
60
+
static inline void __crypto_blake2b_init(struct blake2b_state *state,
61
+
size_t outlen, size_t keylen)
62
+
{
63
+
state->h[0] = BLAKE2B_IV0 ^ (0x01010000 | keylen << 8 | outlen);
64
+
state->h[1] = BLAKE2B_IV1;
65
+
state->h[2] = BLAKE2B_IV2;
66
+
state->h[3] = BLAKE2B_IV3;
67
+
state->h[4] = BLAKE2B_IV4;
68
+
state->h[5] = BLAKE2B_IV5;
69
+
state->h[6] = BLAKE2B_IV6;
70
+
state->h[7] = BLAKE2B_IV7;
71
+
state->t[0] = 0;
72
+
state->t[1] = 0;
73
+
}
74
+
60
75
static inline int crypto_blake2b_init(struct shash_desc *desc)
61
76
{
62
77
const struct blake2b_tfm_ctx *tctx = crypto_shash_ctx(desc->tfm);
63
78
struct blake2b_state *state = shash_desc_ctx(desc);
64
79
unsigned int outlen = crypto_shash_digestsize(desc->tfm);
65
80
66
-
__blake2b_init(state, outlen, tctx->keylen);
81
+
__crypto_blake2b_init(state, outlen, tctx->keylen);
67
82
return tctx->keylen ?
68
83
crypto_shash_update(desc, tctx->key, BLAKE2B_BLOCK_SIZE) : 0;
69
84
}
+10
lib/crypto/Kconfig
+10
lib/crypto/Kconfig
···
28
28
config CRYPTO_LIB_GF128MUL
29
29
tristate
30
30
31
+
config CRYPTO_LIB_BLAKE2B
32
+
tristate
33
+
help
34
+
The BLAKE2b library functions. Select this if your module uses any of
35
+
the functions from <crypto/blake2b.h>.
36
+
37
+
config CRYPTO_LIB_BLAKE2B_ARCH
38
+
bool
39
+
depends on CRYPTO_LIB_BLAKE2B && !UML
40
+
31
41
# BLAKE2s support is always built-in, so there's no CRYPTO_LIB_BLAKE2S option.
32
42
33
43
config CRYPTO_LIB_BLAKE2S_ARCH
+9
lib/crypto/Makefile
+9
lib/crypto/Makefile
···
31
31
32
32
################################################################################
33
33
34
+
obj-$(CONFIG_CRYPTO_LIB_BLAKE2B) += libblake2b.o
35
+
libblake2b-y := blake2b.o
36
+
CFLAGS_blake2b.o := -Wframe-larger-than=4096 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105930
37
+
ifeq ($(CONFIG_CRYPTO_LIB_BLAKE2B_ARCH),y)
38
+
CFLAGS_blake2b.o += -I$(src)/$(SRCARCH)
39
+
endif # CONFIG_CRYPTO_LIB_BLAKE2B_ARCH
40
+
41
+
################################################################################
42
+
34
43
# blake2s is used by the /dev/random driver which is always builtin
35
44
obj-y += blake2s.o
36
45
ifeq ($(CONFIG_CRYPTO_LIB_BLAKE2S_ARCH),y)
+174
lib/crypto/blake2b.c
+174
lib/crypto/blake2b.c
···
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
+
* Copyright 2025 Google LLC
5
+
*
6
+
* This is an implementation of the BLAKE2b hash and PRF functions.
7
+
*
8
+
* Information: https://blake2.net/
9
+
*/
10
+
11
+
#include <crypto/blake2b.h>
12
+
#include <linux/bug.h>
13
+
#include <linux/export.h>
14
+
#include <linux/kernel.h>
15
+
#include <linux/module.h>
16
+
#include <linux/string.h>
17
+
#include <linux/types.h>
18
+
19
+
static const u8 blake2b_sigma[12][16] = {
20
+
{ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 },
21
+
{ 14, 10, 4, 8, 9, 15, 13, 6, 1, 12, 0, 2, 11, 7, 5, 3 },
22
+
{ 11, 8, 12, 0, 5, 2, 15, 13, 10, 14, 3, 6, 7, 1, 9, 4 },
23
+
{ 7, 9, 3, 1, 13, 12, 11, 14, 2, 6, 5, 10, 4, 0, 15, 8 },
24
+
{ 9, 0, 5, 7, 2, 4, 10, 15, 14, 1, 11, 12, 6, 8, 3, 13 },
25
+
{ 2, 12, 6, 10, 0, 11, 8, 3, 4, 13, 7, 5, 15, 14, 1, 9 },
26
+
{ 12, 5, 1, 15, 14, 13, 4, 10, 0, 7, 6, 3, 9, 2, 8, 11 },
27
+
{ 13, 11, 7, 14, 12, 1, 3, 9, 5, 0, 15, 4, 8, 6, 2, 10 },
28
+
{ 6, 15, 14, 9, 11, 3, 0, 8, 12, 2, 13, 7, 1, 4, 10, 5 },
29
+
{ 10, 2, 8, 4, 7, 6, 1, 5, 15, 11, 9, 14, 3, 12, 13, 0 },
30
+
{ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 },
31
+
{ 14, 10, 4, 8, 9, 15, 13, 6, 1, 12, 0, 2, 11, 7, 5, 3 }
32
+
};
33
+
34
+
static inline void blake2b_increment_counter(struct blake2b_ctx *ctx, u32 inc)
35
+
{
36
+
ctx->t[0] += inc;
37
+
ctx->t[1] += (ctx->t[0] < inc);
38
+
}
39
+
40
+
static void __maybe_unused
41
+
blake2b_compress_generic(struct blake2b_ctx *ctx,
42
+
const u8 *data, size_t nblocks, u32 inc)
43
+
{
44
+
u64 m[16];
45
+
u64 v[16];
46
+
int i;
47
+
48
+
WARN_ON(IS_ENABLED(DEBUG) &&
49
+
(nblocks > 1 && inc != BLAKE2B_BLOCK_SIZE));
50
+
51
+
while (nblocks > 0) {
52
+
blake2b_increment_counter(ctx, inc);
53
+
memcpy(m, data, BLAKE2B_BLOCK_SIZE);
54
+
le64_to_cpu_array(m, ARRAY_SIZE(m));
55
+
memcpy(v, ctx->h, 64);
56
+
v[ 8] = BLAKE2B_IV0;
57
+
v[ 9] = BLAKE2B_IV1;
58
+
v[10] = BLAKE2B_IV2;
59
+
v[11] = BLAKE2B_IV3;
60
+
v[12] = BLAKE2B_IV4 ^ ctx->t[0];
61
+
v[13] = BLAKE2B_IV5 ^ ctx->t[1];
62
+
v[14] = BLAKE2B_IV6 ^ ctx->f[0];
63
+
v[15] = BLAKE2B_IV7 ^ ctx->f[1];
64
+
65
+
#define G(r, i, a, b, c, d) do { \
66
+
a += b + m[blake2b_sigma[r][2 * i + 0]]; \
67
+
d = ror64(d ^ a, 32); \
68
+
c += d; \
69
+
b = ror64(b ^ c, 24); \
70
+
a += b + m[blake2b_sigma[r][2 * i + 1]]; \
71
+
d = ror64(d ^ a, 16); \
72
+
c += d; \
73
+
b = ror64(b ^ c, 63); \
74
+
} while (0)
75
+
76
+
#define ROUND(r) do { \
77
+
G(r, 0, v[0], v[ 4], v[ 8], v[12]); \
78
+
G(r, 1, v[1], v[ 5], v[ 9], v[13]); \
79
+
G(r, 2, v[2], v[ 6], v[10], v[14]); \
80
+
G(r, 3, v[3], v[ 7], v[11], v[15]); \
81
+
G(r, 4, v[0], v[ 5], v[10], v[15]); \
82
+
G(r, 5, v[1], v[ 6], v[11], v[12]); \
83
+
G(r, 6, v[2], v[ 7], v[ 8], v[13]); \
84
+
G(r, 7, v[3], v[ 4], v[ 9], v[14]); \
85
+
} while (0)
86
+
ROUND(0);
87
+
ROUND(1);
88
+
ROUND(2);
89
+
ROUND(3);
90
+
ROUND(4);
91
+
ROUND(5);
92
+
ROUND(6);
93
+
ROUND(7);
94
+
ROUND(8);
95
+
ROUND(9);
96
+
ROUND(10);
97
+
ROUND(11);
98
+
99
+
#undef G
100
+
#undef ROUND
101
+
102
+
for (i = 0; i < 8; ++i)
103
+
ctx->h[i] ^= v[i] ^ v[i + 8];
104
+
105
+
data += BLAKE2B_BLOCK_SIZE;
106
+
--nblocks;
107
+
}
108
+
}
109
+
110
+
#ifdef CONFIG_CRYPTO_LIB_BLAKE2B_ARCH
111
+
#include "blake2b.h" /* $(SRCARCH)/blake2b.h */
112
+
#else
113
+
#define blake2b_compress blake2b_compress_generic
114
+
#endif
115
+
116
+
static inline void blake2b_set_lastblock(struct blake2b_ctx *ctx)
117
+
{
118
+
ctx->f[0] = -1;
119
+
}
120
+
121
+
void blake2b_update(struct blake2b_ctx *ctx, const u8 *in, size_t inlen)
122
+
{
123
+
const size_t fill = BLAKE2B_BLOCK_SIZE - ctx->buflen;
124
+
125
+
if (unlikely(!inlen))
126
+
return;
127
+
if (inlen > fill) {
128
+
memcpy(ctx->buf + ctx->buflen, in, fill);
129
+
blake2b_compress(ctx, ctx->buf, 1, BLAKE2B_BLOCK_SIZE);
130
+
ctx->buflen = 0;
131
+
in += fill;
132
+
inlen -= fill;
133
+
}
134
+
if (inlen > BLAKE2B_BLOCK_SIZE) {
135
+
const size_t nblocks = DIV_ROUND_UP(inlen, BLAKE2B_BLOCK_SIZE);
136
+
137
+
blake2b_compress(ctx, in, nblocks - 1, BLAKE2B_BLOCK_SIZE);
138
+
in += BLAKE2B_BLOCK_SIZE * (nblocks - 1);
139
+
inlen -= BLAKE2B_BLOCK_SIZE * (nblocks - 1);
140
+
}
141
+
memcpy(ctx->buf + ctx->buflen, in, inlen);
142
+
ctx->buflen += inlen;
143
+
}
144
+
EXPORT_SYMBOL(blake2b_update);
145
+
146
+
void blake2b_final(struct blake2b_ctx *ctx, u8 *out)
147
+
{
148
+
WARN_ON(IS_ENABLED(DEBUG) && !out);
149
+
blake2b_set_lastblock(ctx);
150
+
memset(ctx->buf + ctx->buflen, 0,
151
+
BLAKE2B_BLOCK_SIZE - ctx->buflen); /* Padding */
152
+
blake2b_compress(ctx, ctx->buf, 1, ctx->buflen);
153
+
cpu_to_le64_array(ctx->h, ARRAY_SIZE(ctx->h));
154
+
memcpy(out, ctx->h, ctx->outlen);
155
+
memzero_explicit(ctx, sizeof(*ctx));
156
+
}
157
+
EXPORT_SYMBOL(blake2b_final);
158
+
159
+
#ifdef blake2b_mod_init_arch
160
+
static int __init blake2b_mod_init(void)
161
+
{
162
+
blake2b_mod_init_arch();
163
+
return 0;
164
+
}
165
+
subsys_initcall(blake2b_mod_init);
166
+
167
+
static void __exit blake2b_mod_exit(void)
168
+
{
169
+
}
170
+
module_exit(blake2b_mod_exit);
171
+
#endif
172
+
173
+
MODULE_DESCRIPTION("BLAKE2b hash function");
174
+
MODULE_LICENSE("GPL");