1/* SPDX-License-Identifier: GPL-2.0-or-later */
 2/*
 3 * ECDH params to be used with kpp API
 4 *
 5 * Copyright (c) 2016, Intel Corporation
 6 * Authors: Salvatore Benedetto <salvatore.benedetto@intel.com>
 
 
 
 
 
 
 7 */
 8#ifndef _CRYPTO_ECDH_
 9#define _CRYPTO_ECDH_
10
11/**
12 * DOC: ECDH Helper Functions
13 *
14 * To use ECDH with the KPP cipher API, the following data structure and
15 * functions should be used.
16 *
17 * The ECC curves known to the ECDH implementation are specified in this
18 * header file.
19 *
20 * To use ECDH with KPP, the following functions should be used to operate on
21 * an ECDH private key. The packet private key that can be set with
22 * the KPP API function call of crypto_kpp_set_secret.
23 */
24
25/* Curves IDs */
26#define ECC_CURVE_NIST_P192	0x0001
27#define ECC_CURVE_NIST_P256	0x0002
28
29/**
30 * struct ecdh - define an ECDH private key
31 *
32 * @curve_id:	ECC curve the key is based on.
33 * @key:	Private ECDH key
34 * @key_size:	Size of the private ECDH key
35 */
36struct ecdh {
37	unsigned short curve_id;
38	char *key;
39	unsigned short key_size;
40};
41
42/**
43 * crypto_ecdh_key_len() - Obtain the size of the private ECDH key
44 * @params:	private ECDH key
45 *
46 * This function returns the packet ECDH key size. A caller can use that
47 * with the provided ECDH private key reference to obtain the required
48 * memory size to hold a packet key.
49 *
50 * Return: size of the key in bytes
51 */
52unsigned int crypto_ecdh_key_len(const struct ecdh *params);
53
54/**
55 * crypto_ecdh_encode_key() - encode the private key
56 * @buf:	Buffer allocated by the caller to hold the packet ECDH
57 *		private key. The buffer should be at least crypto_ecdh_key_len
58 *		bytes in size.
59 * @len:	Length of the packet private key buffer
60 * @p:		Buffer with the caller-specified private key
61 *
62 * The ECDH implementations operate on a packet representation of the private
63 * key.
64 *
65 * Return:	-EINVAL if buffer has insufficient size, 0 on success
66 */
67int crypto_ecdh_encode_key(char *buf, unsigned int len, const struct ecdh *p);
68
69/**
70 * crypto_ecdh_decode_key() - decode a private key
71 * @buf:	Buffer holding a packet key that should be decoded
72 * @len:	Length of the packet private key buffer
73 * @p:		Buffer allocated by the caller that is filled with the
74 *		unpacked ECDH private key.
75 *
76 * The unpacking obtains the private key by pointing @p to the correct location
77 * in @buf. Thus, both pointers refer to the same memory.
78 *
79 * Return:	-EINVAL if buffer has insufficient size, 0 on success
80 */
81int crypto_ecdh_decode_key(const char *buf, unsigned int len, struct ecdh *p);
82
83#endif

 
 1/*
 2 * ECDH params to be used with kpp API
 3 *
 4 * Copyright (c) 2016, Intel Corporation
 5 * Authors: Salvatore Benedetto <salvatore.benedetto@intel.com>
 6 *
 7 * This program is free software; you can redistribute it and/or modify it
 8 * under the terms of the GNU General Public License as published by the Free
 9 * Software Foundation; either version 2 of the License, or (at your option)
10 * any later version.
11 *
12 */
13#ifndef _CRYPTO_ECDH_
14#define _CRYPTO_ECDH_
15
16/**
17 * DOC: ECDH Helper Functions
18 *
19 * To use ECDH with the KPP cipher API, the following data structure and
20 * functions should be used.
21 *
22 * The ECC curves known to the ECDH implementation are specified in this
23 * header file.
24 *
25 * To use ECDH with KPP, the following functions should be used to operate on
26 * an ECDH private key. The packet private key that can be set with
27 * the KPP API function call of crypto_kpp_set_secret.
28 */
29
30/* Curves IDs */
31#define ECC_CURVE_NIST_P192	0x0001
32#define ECC_CURVE_NIST_P256	0x0002
33
34/**
35 * struct ecdh - define an ECDH private key
36 *
37 * @curve_id:	ECC curve the key is based on.
38 * @key:	Private ECDH key
39 * @key_size:	Size of the private ECDH key
40 */
41struct ecdh {
42	unsigned short curve_id;
43	char *key;
44	unsigned short key_size;
45};
46
47/**
48 * crypto_ecdh_key_len() - Obtain the size of the private ECDH key
49 * @params:	private ECDH key
50 *
51 * This function returns the packet ECDH key size. A caller can use that
52 * with the provided ECDH private key reference to obtain the required
53 * memory size to hold a packet key.
54 *
55 * Return: size of the key in bytes
56 */
57unsigned int crypto_ecdh_key_len(const struct ecdh *params);
58
59/**
60 * crypto_ecdh_encode_key() - encode the private key
61 * @buf:	Buffer allocated by the caller to hold the packet ECDH
62 *		private key. The buffer should be at least crypto_ecdh_key_len
63 *		bytes in size.
64 * @len:	Length of the packet private key buffer
65 * @p:		Buffer with the caller-specified private key
66 *
67 * The ECDH implementations operate on a packet representation of the private
68 * key.
69 *
70 * Return:	-EINVAL if buffer has insufficient size, 0 on success
71 */
72int crypto_ecdh_encode_key(char *buf, unsigned int len, const struct ecdh *p);
73
74/**
75 * crypto_ecdh_decode_key() - decode a private key
76 * @buf:	Buffer holding a packet key that should be decoded
77 * @len:	Length of the packet private key buffer
78 * @p:		Buffer allocated by the caller that is filled with the
79 *		unpacked ECDH private key.
80 *
81 * The unpacking obtains the private key by pointing @p to the correct location
82 * in @buf. Thus, both pointers refer to the same memory.
83 *
84 * Return:	-EINVAL if buffer has insufficient size, 0 on success
85 */
86int crypto_ecdh_decode_key(const char *buf, unsigned int len, struct ecdh *p);
87
88#endif