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 */