b9f8890c066e3f73393301dce74260ca3042584f
[strongswan.git] / Source / charon / utils / randomizer.h
1 /**
2 * @file randomizer.h
3 *
4 * @brief Class used to get random and pseudo random values
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 Object representing an randomizer
32 *
33 * This class is thread save as file system read calls are thread save...
34 */
35 struct randomizer_t {
36
37 /**
38 * @brief Reads a specific number of bytes from random device.
39 *
40 * @param this calling randomizer_t object
41 * @param bytes Number of bytes to read
42 * @param[out] buffer Pointer to buffer where to write the data in.
43 * Size of buffer has to be at least bytes.
44 * @return
45 * - SUCCESS
46 * - FAILED
47 */
48 status_t (*get_random_bytes) (randomizer_t *this,size_t bytes, u_int8_t *buffer);
49
50 /**
51 * @brief Allocates space and writes in random bytes
52 *
53 * @param this calling randomizer_t object
54 * @param bytes Number of bytes to allocate
55 * @param[out] chunk chunk which will hold the allocated random bytes
56 * @return
57 * - SUCCESS
58 * - OUT_OF_RES
59 * - FAILED
60 */
61 status_t (*allocate_random_bytes) (randomizer_t *this, size_t bytes, chunk_t *chunk);
62
63 /**
64 * @brief Reads a specific number of bytes from pseudo random device.
65 *
66 * @param this calling randomizer_t object
67 * @param bytes Number of bytes to read
68 * @param[out] buffer Pointer to buffer where to write the data in.
69 * Size of buffer has to be at least bytes.
70 * @return
71 * - SUCCESS
72 * - FAILED
73 */
74 status_t (*get_pseudo_random_bytes) (randomizer_t *this,size_t bytes, u_int8_t *buffer);
75
76 /**
77 * @brief Allocates space and writes in pseudo random bytes
78 *
79 * @param this calling randomizer_t object
80 * @param bytes Number of bytes to allocate
81 * @param[out] chunk chunk which will hold the allocated random bytes
82 * @return
83 * - SUCCESS
84 * - OUT_OF_RES
85 * - FAILED
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 * @return
94 * SUCCESS in any case
95 */
96 status_t (*destroy) (randomizer_t *this);
97 };
98
99 /**
100 * @brief Create an randomizer_t object
101 *
102 * @return
103 * - created randomizer_t, or
104 * - NULL if failed
105 */
106 randomizer_t *randomizer_create();
107
108 /**
109 * @brief Create 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, or
115 * - NULL if failed
116 */
117 randomizer_t *randomizer_create_on_devices(char * random_dev_name,char * prandom_dev_name);
118
119 #endif /*RANDOMIZER_H_*/