- return value cleanup
[strongswan.git] / Source / charon / utils / randomizer.h
1 /**
2 * @file randomizer.h
3 *
4 * @brief Interface of randomizer_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 RANDOMIZER_H_
24 #define RANDOMIZER_H_
25
26 #include <types.h>
27
28 typedef struct randomizer_t randomizer_t;
29
30 /**
31 * @brief Class used to get random and pseudo random values.
32 *
33 * This class is thread save as file system read calls are thread save.
34 *
35 * @ingroup utils
36 */
37 struct randomizer_t {
38
39 /**
40 * @brief Reads a specific number of bytes from random device.
41 *
42 * @param this calling randomizer_t object
43 * @param bytes number of bytes to read
44 * @param[out] buffer pointer to buffer where to write the data in.
45 * Size of buffer has to be at least bytes.
46 * @return
47 * - SUCCESS
48 * - FAILED if random device could not be opened
49 */
50 status_t (*get_random_bytes) (randomizer_t *this,size_t bytes, u_int8_t *buffer);
51
52 /**
53 * @brief Allocates space and writes in random bytes.
54 *
55 * @param this calling randomizer_t object
56 * @param bytes number of bytes to allocate
57 * @param[out] chunk chunk which will hold the allocated random bytes
58 * @return
59 * - SUCCESS
60 * - FAILED if random device could not be opened
61 */
62 status_t (*allocate_random_bytes) (randomizer_t *this, size_t bytes, chunk_t *chunk);
63
64 /**
65 * @brief Reads a specific number of bytes from pseudo random device.
66 *
67 * @param this calling randomizer_t object
68 * @param bytes number of bytes to read
69 * @param[out] buffer pointer to buffer where to write the data in.
70 * size of buffer has to be at least bytes.
71 * @return
72 * - SUCCESS
73 * - FAILED if random device could not be opened
74 */
75 status_t (*get_pseudo_random_bytes) (randomizer_t *this,size_t bytes, u_int8_t *buffer);
76
77 /**
78 * @brief Allocates space and writes in pseudo random bytes.
79 *
80 * @param this calling randomizer_t object
81 * @param bytes number of bytes to allocate
82 * @param[out] chunk chunk which will hold the allocated random bytes
83 * @return
84 * - SUCCESS
85 * - FAILED if random device could not be opened
86 */
87 status_t (*allocate_pseudo_random_bytes) (randomizer_t *this, size_t bytes, chunk_t *chunk);
88
89 /**
90 * @brief Destroys a randomizer_t object.
91 *
92 * @param this randomizer_t object to destroy
93 */
94 void (*destroy) (randomizer_t *this);
95 };
96
97 /**
98 * @brief Creates a randomizer_t object
99 *
100 * @return
101 * - created randomizer_t, or
102 * - NULL if failed
103 *
104 * @ingroup utils
105 */
106 randomizer_t *randomizer_create();
107
108 /**
109 * @brief Creates an randomizer_t object with specific random device names.
110 *
111 * @param random_dev_name device name for random values, etc /dev/random
112 * @param prandom_dev_name device name for pseudo random values, etc /dev/urandom
113 * @return
114 * - created randomizer_t
115 * - NULL if failed
116 *
117 * @ingroup utils
118 */
119 randomizer_t *randomizer_create_on_devices(char * random_dev_name,char * prandom_dev_name);
120
121 #endif /*RANDOMIZER_H_*/