c3ca32524be8d08dcf367e1b795a9e372bd684ff
[strongswan.git] / Source / charon / transforms / diffie_hellman.h
1 /**
2 * @file diffie_hellman.h
3 *
4 * @brief Interface of diffie_hellman_t.
5 *
6 */
7
8 /*
9 * Copyright (C) 2005 Jan Hutter, Martin Willi
10 * Hochschule fuer Technik Rapperswil
11 *
12 * This program is free software; you can redistribute it and/or modify it
13 * under the terms of the GNU General Public License as published by the
14 * Free Software Foundation; either version 2 of the License, or (at your
15 * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
16 *
17 * This program is distributed in the hope that it will be useful, but
18 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
19 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
20 * for more details.
21 */
22
23 #ifndef DIFFIE_HELLMAN_H_
24 #define DIFFIE_HELLMAN_H_
25
26 #include <types.h>
27
28
29 typedef enum diffie_hellman_group_t diffie_hellman_group_t;
30
31 /**
32 * @brief Diffie-Hellman group.
33 *
34 * The modulus (or group) to use for a Diffie-Hellman calculation.
35 *
36 * @see IKEv2 draft 3.3.2 and RFC 3526.
37 */
38 enum diffie_hellman_group_t {
39 MODP_UNDEFINED = 1024,
40 MODP_768_BIT = 1,
41 MODP_1024_BIT = 2,
42 MODP_1536_BIT = 5,
43 MODP_2048_BIT = 14,
44 MODP_3072_BIT = 15,
45 MODP_4096_BIT = 16,
46 MODP_6144_BIT = 17,
47 MODP_8192_BIT = 18
48 };
49
50 /**
51 * string mappings for diffie_hellman_group_t
52 */
53 extern mapping_t diffie_hellman_group_m[];
54
55
56 typedef struct diffie_hellman_t diffie_hellman_t;
57
58 /**
59 * @brief Implementation of the widely used Diffie-Hellman algorithm.
60 *
61 * @ingroup transforms
62 */
63 struct diffie_hellman_t {
64
65 /**
66 * @brief Returns the shared secret of this diffie hellman exchange.
67 *
68 * @warning Space for returned secret is allocated and must be
69 * freed by the caller.
70 *
71 * @param this calling diffie_hellman_t object
72 * @param[out] secret shared secret will be written into this chunk
73 * @return
74 * - SUCCESS, or
75 * - FAILED if not both DH values are set
76 */
77 status_t (*get_shared_secret) (diffie_hellman_t *this, chunk_t *secret);
78
79 /**
80 * @brief Sets the public value of partner.
81 *
82 * @warning chunk gets copied
83 *
84 * @param this calling diffie_hellman_t object
85 * @param public_value public value of partner
86 */
87 void (*set_other_public_value) (diffie_hellman_t *this, chunk_t public_value);
88
89 /**
90 * @brief Gets the public value of partner.
91 *
92 * @warning chunk gets copied
93 *
94 * @param this calling diffie_hellman_t object
95 * @param[out] public_value public value of partner is stored at this location
96 * @return
97 * - SUCCESS, or
98 * - FAILED if other public value not set
99 */
100 status_t (*get_other_public_value) (diffie_hellman_t *this, chunk_t *public_value);
101
102 /**
103 * @brief Gets the public value of caller
104 *
105 * @warning chunk gets copied
106 *
107 * @param this calling diffie_hellman_t object
108 * @param[out] public_value public value of caller is stored at this location
109 * @return
110 * - SUCCESS, or
111 * - FAILED if not computed
112 */
113 status_t (*get_my_public_value) (diffie_hellman_t *this, chunk_t *public_value);
114
115 /**
116 * @brief Destroys an diffie_hellman_t object.
117 *
118 * @param this diffie_hellman_t object to destroy
119 */
120 void (*destroy) (diffie_hellman_t *this);
121 };
122
123 /**
124 * @brief Creates a new diffie_hellman_t object.
125 *
126 * The first diffie hellman public value gets automatically created.
127 *
128 * @param dh_group_number Diffie Hellman group number to use
129 * @return
130 * - diffie_hellman_t object
131 * - NULL if dh group not supported
132 *
133 * @ingroup transforms
134 */
135 diffie_hellman_t *diffie_hellman_create(diffie_hellman_group_t dh_group_number);
136
137 #endif /*DIFFIE_HELLMAN_H_*/