1/*
2 * Copyright 2001-2018 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the OpenSSL license (the "License").  You may not use
5 * this file except in compliance with the License.  You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
8 */
9
10#include "eng_local.h"
11
12static ENGINE_TABLE *dh_table = NULL;
13static const int dummy_nid = 1;
14
15void ENGINE_unregister_DH(ENGINE *e)
16{
17    engine_table_unregister(&dh_table, e);
18}
19
20static void engine_unregister_all_DH(void)
21{
22    engine_table_cleanup(&dh_table);
23}
24
25int ENGINE_register_DH(ENGINE *e)
26{
27    if (e->dh_meth)
28        return engine_table_register(&dh_table,
29                                     engine_unregister_all_DH, e, &dummy_nid,
30                                     1, 0);
31    return 1;
32}
33
34void ENGINE_register_all_DH(void)
35{
36    ENGINE *e;
37
38    for (e = ENGINE_get_first(); e; e = ENGINE_get_next(e))
39        ENGINE_register_DH(e);
40}
41
42int ENGINE_set_default_DH(ENGINE *e)
43{
44    if (e->dh_meth)
45        return engine_table_register(&dh_table,
46                                     engine_unregister_all_DH, e, &dummy_nid,
47                                     1, 1);
48    return 1;
49}
50
51/*
52 * Exposed API function to get a functional reference from the implementation
53 * table (ie. try to get a functional reference from the tabled structural
54 * references).
55 */
56ENGINE *ENGINE_get_default_DH(void)
57{
58    return engine_table_select(&dh_table, dummy_nid);
59}
60
61/* Obtains an DH implementation from an ENGINE functional reference */
62const DH_METHOD *ENGINE_get_DH(const ENGINE *e)
63{
64    return e->dh_meth;
65}
66
67/* Sets an DH implementation in an ENGINE structure */
68int ENGINE_set_DH(ENGINE *e, const DH_METHOD *dh_meth)
69{
70    e->dh_meth = dh_meth;
71    return 1;
72}
73