1// SPDX-License-Identifier: GPL-2.0-or-later
 2/*
 3 * Copyright (c) 2016, Intel Corporation
 4 * Authors: Salvatore Benedetto <salvatore.benedetto@intel.com>
 
 
 
 
 
 5 */
 6#include <linux/kernel.h>
 7#include <linux/export.h>
 8#include <linux/err.h>
 9#include <linux/string.h>
10#include <crypto/ecdh.h>
11#include <crypto/kpp.h>
12
13#define ECDH_KPP_SECRET_MIN_SIZE (sizeof(struct kpp_secret) + sizeof(short))
14
15static inline u8 *ecdh_pack_data(void *dst, const void *src, size_t sz)
16{
17	memcpy(dst, src, sz);
18	return dst + sz;
19}
20
21static inline const u8 *ecdh_unpack_data(void *dst, const void *src, size_t sz)
22{
23	memcpy(dst, src, sz);
24	return src + sz;
25}
26
27unsigned int crypto_ecdh_key_len(const struct ecdh *params)
28{
29	return ECDH_KPP_SECRET_MIN_SIZE + params->key_size;
30}
31EXPORT_SYMBOL_GPL(crypto_ecdh_key_len);
32
33int crypto_ecdh_encode_key(char *buf, unsigned int len,
34			   const struct ecdh *params)
35{
36	u8 *ptr = buf;
37	struct kpp_secret secret = {
38		.type = CRYPTO_KPP_SECRET_TYPE_ECDH,
39		.len = len
40	};
41
42	if (unlikely(!buf))
43		return -EINVAL;
44
45	if (len != crypto_ecdh_key_len(params))
46		return -EINVAL;
47
48	ptr = ecdh_pack_data(ptr, &secret, sizeof(secret));
 
49	ptr = ecdh_pack_data(ptr, &params->key_size, sizeof(params->key_size));
50	ecdh_pack_data(ptr, params->key, params->key_size);
51
52	return 0;
53}
54EXPORT_SYMBOL_GPL(crypto_ecdh_encode_key);
55
56int crypto_ecdh_decode_key(const char *buf, unsigned int len,
57			   struct ecdh *params)
58{
59	const u8 *ptr = buf;
60	struct kpp_secret secret;
61
62	if (unlikely(!buf || len < ECDH_KPP_SECRET_MIN_SIZE))
63		return -EINVAL;
64
65	ptr = ecdh_unpack_data(&secret, ptr, sizeof(secret));
66	if (secret.type != CRYPTO_KPP_SECRET_TYPE_ECDH)
67		return -EINVAL;
68
69	if (unlikely(len < secret.len))
70		return -EINVAL;
71
72	ptr = ecdh_unpack_data(&params->key_size, ptr, sizeof(params->key_size));
73	if (secret.len != crypto_ecdh_key_len(params))
74		return -EINVAL;
75
76	/* Don't allocate memory. Set pointer to data
77	 * within the given buffer
78	 */
79	params->key = (void *)ptr;
80
81	return 0;
82}
83EXPORT_SYMBOL_GPL(crypto_ecdh_decode_key);

 
 1/*
 2 * Copyright (c) 2016, Intel Corporation
 3 * Authors: Salvatore Benedetto <salvatore.benedetto@intel.com>
 4 *
 5 * This program is free software; you can redistribute it and/or
 6 * modify it under the terms of the GNU General Public License
 7 * as published by the Free Software Foundation; either version
 8 * 2 of the License, or (at your option) any later version.
 9 */
10#include <linux/kernel.h>
11#include <linux/export.h>
12#include <linux/err.h>
13#include <linux/string.h>
14#include <crypto/ecdh.h>
15#include <crypto/kpp.h>
16
17#define ECDH_KPP_SECRET_MIN_SIZE (sizeof(struct kpp_secret) + 2 * sizeof(short))
18
19static inline u8 *ecdh_pack_data(void *dst, const void *src, size_t sz)
20{
21	memcpy(dst, src, sz);
22	return dst + sz;
23}
24
25static inline const u8 *ecdh_unpack_data(void *dst, const void *src, size_t sz)
26{
27	memcpy(dst, src, sz);
28	return src + sz;
29}
30
31unsigned int crypto_ecdh_key_len(const struct ecdh *params)
32{
33	return ECDH_KPP_SECRET_MIN_SIZE + params->key_size;
34}
35EXPORT_SYMBOL_GPL(crypto_ecdh_key_len);
36
37int crypto_ecdh_encode_key(char *buf, unsigned int len,
38			   const struct ecdh *params)
39{
40	u8 *ptr = buf;
41	struct kpp_secret secret = {
42		.type = CRYPTO_KPP_SECRET_TYPE_ECDH,
43		.len = len
44	};
45
46	if (unlikely(!buf))
47		return -EINVAL;
48
49	if (len != crypto_ecdh_key_len(params))
50		return -EINVAL;
51
52	ptr = ecdh_pack_data(ptr, &secret, sizeof(secret));
53	ptr = ecdh_pack_data(ptr, &params->curve_id, sizeof(params->curve_id));
54	ptr = ecdh_pack_data(ptr, &params->key_size, sizeof(params->key_size));
55	ecdh_pack_data(ptr, params->key, params->key_size);
56
57	return 0;
58}
59EXPORT_SYMBOL_GPL(crypto_ecdh_encode_key);
60
61int crypto_ecdh_decode_key(const char *buf, unsigned int len,
62			   struct ecdh *params)
63{
64	const u8 *ptr = buf;
65	struct kpp_secret secret;
66
67	if (unlikely(!buf || len < ECDH_KPP_SECRET_MIN_SIZE))
68		return -EINVAL;
69
70	ptr = ecdh_unpack_data(&secret, ptr, sizeof(secret));
71	if (secret.type != CRYPTO_KPP_SECRET_TYPE_ECDH)
72		return -EINVAL;
73
74	ptr = ecdh_unpack_data(&params->curve_id, ptr, sizeof(params->curve_id));
 
 
75	ptr = ecdh_unpack_data(&params->key_size, ptr, sizeof(params->key_size));
76	if (secret.len != crypto_ecdh_key_len(params))
77		return -EINVAL;
78
79	/* Don't allocate memory. Set pointer to data
80	 * within the given buffer
81	 */
82	params->key = (void *)ptr;
83
84	return 0;
85}
86EXPORT_SYMBOL_GPL(crypto_ecdh_decode_key);