openssl: Use separate DRBG for RNG_STRONG and RNG_TRUE with OpenSSL 1.1.1
[strongswan.git] / src / libstrongswan / plugins / openssl / openssl_rng.c
1 /*
2 * Copyright (C) 2012-2018 Tobias Brunner
3 * HSR Hochschule fuer Technik Rapperswil
4 *
5 * Copyright (C) 2012 Aleksandr Grinberg
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a copy
8 * of this software and associated documentation files (the "Software"), to deal
9 * in the Software without restriction, including without limitation the rights
10 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11 * copies of the Software, and to permit persons to whom the Software is
12 * furnished to do so, subject to the following conditions:
13 *
14 * The above copyright notice and this permission notice shall be included in
15 * all copies or substantial portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
20 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
23 * THE SOFTWARE.
24 */
25
26 #include <library.h>
27 #include <utils/debug.h>
28
29 #include <openssl/rand.h>
30
31 #include "openssl_rng.h"
32
33 typedef struct private_openssl_rng_t private_openssl_rng_t;
34
35 /**
36 * Private data of openssl_rng_t
37 */
38 struct private_openssl_rng_t {
39
40 /**
41 * Public part of this class.
42 */
43 openssl_rng_t public;
44
45 /**
46 * Quality of randomness
47 */
48 rng_quality_t quality;
49 };
50
51 METHOD(rng_t, get_bytes, bool,
52 private_openssl_rng_t *this, size_t bytes, uint8_t *buffer)
53 {
54 #if OPENSSL_VERSION_NUMBER >= 0x1010100fL
55 if (this->quality > RNG_WEAK)
56 { /* use a separate DRBG for data we wan't to keep private, compared
57 * to e.g. nonces */
58 return RAND_priv_bytes((char*)buffer, bytes) == 1;
59 }
60 #endif
61 return RAND_bytes((char*)buffer, bytes) == 1;
62 }
63
64 METHOD(rng_t, allocate_bytes, bool,
65 private_openssl_rng_t *this, size_t bytes, chunk_t *chunk)
66 {
67 *chunk = chunk_alloc(bytes);
68 if (!get_bytes(this, chunk->len, chunk->ptr))
69 {
70 chunk_free(chunk);
71 return FALSE;
72 }
73 return TRUE;
74 }
75
76 METHOD(rng_t, destroy, void,
77 private_openssl_rng_t *this)
78 {
79 free(this);
80 }
81
82 /*
83 * Described in header.
84 */
85 openssl_rng_t *openssl_rng_create(rng_quality_t quality)
86 {
87 private_openssl_rng_t *this;
88
89 INIT(this,
90 .public = {
91 .rng = {
92 .get_bytes = _get_bytes,
93 .allocate_bytes = _allocate_bytes,
94 .destroy = _destroy,
95 },
96 },
97 .quality = quality,
98 );
99
100 return &this->public;
101 }