1/* SPDX-License-Identifier: GPL-2.0 */
2
3#ifndef _CRYPTO_INTERNAL_CHACHA_H
4#define _CRYPTO_INTERNAL_CHACHA_H
5
6#include <crypto/chacha.h>
7#include <crypto/internal/skcipher.h>
8#include <linux/crypto.h>
9
10struct chacha_ctx {
11 u32 key[8];
12 int nrounds;
13};
14
15static inline int chacha_setkey(struct crypto_skcipher *tfm, const u8 *key,
16 unsigned int keysize, int nrounds)
17{
18 struct chacha_ctx *ctx = crypto_skcipher_ctx(tfm);
19 int i;
20
21 if (keysize != CHACHA_KEY_SIZE)
22 return -EINVAL;
23
24 for (i = 0; i < ARRAY_SIZE(ctx->key); i++)
25 ctx->key[i] = get_unaligned_le32(p: key + i * sizeof(u32));
26
27 ctx->nrounds = nrounds;
28 return 0;
29}
30
31static inline int chacha20_setkey(struct crypto_skcipher *tfm, const u8 *key,
32 unsigned int keysize)
33{
34 return chacha_setkey(tfm, key, keysize, nrounds: 20);
35}
36
37static inline int chacha12_setkey(struct crypto_skcipher *tfm, const u8 *key,
38 unsigned int keysize)
39{
40 return chacha_setkey(tfm, key, keysize, nrounds: 12);
41}
42
43#endif /* _CRYPTO_CHACHA_H */
44

source code of linux/include/crypto/internal/chacha.h