1/* SPDX-License-Identifier: GPL-2.0 OR MIT */
2/*
3 * Helper functions for BLAKE2b implementations.
4 * Keep this in sync with the corresponding BLAKE2s header.
5 */
6
7#ifndef _CRYPTO_INTERNAL_BLAKE2B_H
8#define _CRYPTO_INTERNAL_BLAKE2B_H
9
10#include <crypto/blake2b.h>
11#include <crypto/internal/hash.h>
12#include <linux/string.h>
13
14void blake2b_compress_generic(struct blake2b_state *state,
15			      const u8 *block, size_t nblocks, u32 inc);
16
17static inline void blake2b_set_lastblock(struct blake2b_state *state)
18{
19	state->f[0] = -1;
20}
21
22typedef void (*blake2b_compress_t)(struct blake2b_state *state,
23				   const u8 *block, size_t nblocks, u32 inc);
24
25static inline void __blake2b_update(struct blake2b_state *state,
26				    const u8 *in, size_t inlen,
27				    blake2b_compress_t compress)
28{
29	const size_t fill = BLAKE2B_BLOCK_SIZE - state->buflen;
30
31	if (unlikely(!inlen))
32		return;
33	if (inlen > fill) {
34		memcpy(state->buf + state->buflen, in, fill);
35		(*compress)(state, state->buf, 1, BLAKE2B_BLOCK_SIZE);
36		state->buflen = 0;
37		in += fill;
38		inlen -= fill;
39	}
40	if (inlen > BLAKE2B_BLOCK_SIZE) {
41		const size_t nblocks = DIV_ROUND_UP(inlen, BLAKE2B_BLOCK_SIZE);
42		/* Hash one less (full) block than strictly possible */
43		(*compress)(state, in, nblocks - 1, BLAKE2B_BLOCK_SIZE);
44		in += BLAKE2B_BLOCK_SIZE * (nblocks - 1);
45		inlen -= BLAKE2B_BLOCK_SIZE * (nblocks - 1);
46	}
47	memcpy(state->buf + state->buflen, in, inlen);
48	state->buflen += inlen;
49}
50
51static inline void __blake2b_final(struct blake2b_state *state, u8 *out,
52				   blake2b_compress_t compress)
53{
54	int i;
55
56	blake2b_set_lastblock(state);
57	memset(state->buf + state->buflen, 0,
58	       BLAKE2B_BLOCK_SIZE - state->buflen); /* Padding */
59	(*compress)(state, state->buf, 1, state->buflen);
60	for (i = 0; i < ARRAY_SIZE(state->h); i++)
61		__cpu_to_le64s(&state->h[i]);
62	memcpy(out, state->h, state->outlen);
63}
64
65/* Helper functions for shash implementations of BLAKE2b */
66
67struct blake2b_tfm_ctx {
68	u8 key[BLAKE2B_KEY_SIZE];
69	unsigned int keylen;
70};
71
72static inline int crypto_blake2b_setkey(struct crypto_shash *tfm,
73					const u8 *key, unsigned int keylen)
74{
75	struct blake2b_tfm_ctx *tctx = crypto_shash_ctx(tfm);
76
77	if (keylen == 0 || keylen > BLAKE2B_KEY_SIZE)
78		return -EINVAL;
79
80	memcpy(tctx->key, key, keylen);
81	tctx->keylen = keylen;
82
83	return 0;
84}
85
86static inline int crypto_blake2b_init(struct shash_desc *desc)
87{
88	const struct blake2b_tfm_ctx *tctx = crypto_shash_ctx(desc->tfm);
89	struct blake2b_state *state = shash_desc_ctx(desc);
90	unsigned int outlen = crypto_shash_digestsize(desc->tfm);
91
92	__blake2b_init(state, outlen, tctx->key, tctx->keylen);
93	return 0;
94}
95
96static inline int crypto_blake2b_update(struct shash_desc *desc,
97					const u8 *in, unsigned int inlen,
98					blake2b_compress_t compress)
99{
100	struct blake2b_state *state = shash_desc_ctx(desc);
101
102	__blake2b_update(state, in, inlen, compress);
103	return 0;
104}
105
106static inline int crypto_blake2b_final(struct shash_desc *desc, u8 *out,
107				       blake2b_compress_t compress)
108{
109	struct blake2b_state *state = shash_desc_ctx(desc);
110
111	__blake2b_final(state, out, compress);
112	return 0;
113}
114
115#endif /* _CRYPTO_INTERNAL_BLAKE2B_H */
116