iv_gen: Provide external sequence number (IKE, ESP)
[strongswan.git] / src / libstrongswan / crypto / iv / iv_gen.h
1 /*
2 * Copyright (C) 2013 Tobias Brunner
3 * Hochschule fuer Technik Rapperswil
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License as published by the
7 * Free Software Foundation; either version 2 of the License, or (at your
8 * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
9 *
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
12 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * for more details.
14 */
15
16 /**
17 * @defgroup iv iv
18 * @{ @ingroup crypto
19 */
20
21 #ifndef IV_GEN_H_
22 #define IV_GEN_H_
23
24 typedef struct iv_gen_t iv_gen_t;
25
26 #include <library.h>
27
28 /**
29 * Generic interface for initialization vector (IV) generators.
30 */
31 struct iv_gen_t {
32
33 /**
34 * Generates an IV and writes it into the buffer.
35 *
36 * @param seq external sequence number
37 * @param size size of IV in bytes
38 * @param buffer pointer where the generated IV will be written
39 * @return TRUE if IV allocation was successful, FALSE otherwise
40 */
41 bool (*get_iv)(iv_gen_t *this, u_int64_t seq, size_t size,
42 u_int8_t *buffer) __attribute__((warn_unused_result));
43
44 /**
45 * Generates an IV and allocates space for it.
46 *
47 * @param seq external sequence number
48 * @param size size of IV in bytes
49 * @param chunk chunk which will hold the generated IV
50 * @return TRUE if IV allocation was successful, FALSE otherwise
51 */
52 bool (*allocate_iv)(iv_gen_t *this, u_int64_t seq, size_t size,
53 chunk_t *chunk) __attribute__((warn_unused_result));
54
55 /**
56 * Destroys an IV generator object.
57 */
58 void (*destroy)(iv_gen_t *this);
59 };
60
61 #endif /** IV_GEN_H_ @}*/