1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * HKDF: HMAC-based Key Derivation Function (HKDF), RFC 5869
4  *
5  * Extracted from fs/crypto/hkdf.c, which has
6  * Copyright 2019 Google LLC
7  */
8 
9 #ifndef _CRYPTO_HKDF_H
10 #define _CRYPTO_HKDF_H
11 
12 #include <crypto/hash.h>
13 
14 int hkdf_extract(struct crypto_shash *hmac_tfm, const u8 *ikm,
15 		 unsigned int ikmlen, const u8 *salt, unsigned int saltlen,
16 		 u8 *prk);
17 int hkdf_expand(struct crypto_shash *hmac_tfm,
18 		const u8 *info, unsigned int infolen,
19 		u8 *okm, unsigned int okmlen);
20 #endif
21