1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
|
/**
* @file randomizer.c
*
* @brief Implementation of randomizer_t.
*
*/
/*
* Copyright (C) 2005 Jan Hutter, Martin Willi
* Hochschule fuer Technik Rapperswil
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* for more details.
*/
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include "randomizer.h"
#include <utils/allocator.h>
typedef struct private_randomizer_t private_randomizer_t;
/**
* Private data of an randomizer_t object.
*/
struct private_randomizer_t {
/**
* Public randomizer_t interface.
*/
randomizer_t public;
/**
* @brief Reads a specific number of bytes from random or pseudo random device.
*
* @param this calling object
* @param pseudo_random TRUE, if from pseudo random bytes should be read,
* FALSE for true random bytes
* @param bytes number of bytes to read
* @param[out] buffer pointer to buffer where to write the data in.
* Size of buffer has to be at least bytes.
*/
status_t (*get_bytes_from_device) (private_randomizer_t *this,bool pseudo_random, size_t bytes, u_int8_t *buffer);
};
/**
* Implementation of private_randomizer_t.get_bytes_from_device.
*/
static status_t get_bytes_from_device(private_randomizer_t *this,bool pseudo_random, size_t bytes, u_int8_t *buffer)
{
size_t ndone;
int device;
size_t got;
char * device_name;
device_name = pseudo_random ? RANDOM_DEVICE : PSEUDO_RANDOM_DEVICE;
device = open(device_name, 0);
if (device < 0) {
return FAILED;
}
ndone = 0;
/* read until nbytes are read */
while (ndone < bytes)
{
got = read(device, buffer + ndone, bytes - ndone);
if (got <= 0) {
close(device);
return FAILED;
}
ndone += got;
}
close(device);
return SUCCESS;
}
/**
* Implementation of randomizer_t.get_random_bytes.
*/
static status_t get_random_bytes(private_randomizer_t *this,size_t bytes, u_int8_t *buffer)
{
return this->get_bytes_from_device(this, FALSE, bytes, buffer);
}
/**
* Implementation of randomizer_t.allocate_random_bytes.
*/
static status_t allocate_random_bytes(private_randomizer_t *this, size_t bytes, chunk_t *chunk)
{
status_t status;
chunk->len = bytes;
chunk->ptr = allocator_alloc(bytes);
status = this->get_bytes_from_device(this, FALSE, bytes, chunk->ptr);
if (status != SUCCESS)
{
allocator_free(chunk->ptr);
}
return status;
}
/**
* Implementation of randomizer_t.get_pseudo_random_bytes.
*/
static status_t get_pseudo_random_bytes(private_randomizer_t *this,size_t bytes, u_int8_t *buffer)
{
return (this->get_bytes_from_device(this, TRUE, bytes, buffer));
}
/**
* Implementation of randomizer_t.allocate_pseudo_random_bytes.
*/
static status_t allocate_pseudo_random_bytes(private_randomizer_t *this, size_t bytes, chunk_t *chunk)
{
status_t status;
chunk->len = bytes;
chunk->ptr = allocator_alloc(bytes);
status = this->get_bytes_from_device(this, TRUE, bytes, chunk->ptr);
if (status != SUCCESS)
{
allocator_free(chunk->ptr);
}
return status;
}
/**
* Implementation of randomizer_t.destroy.
*/
static void destroy(private_randomizer_t *this)
{
allocator_free(this);
}
/*
* Described in header.
*/
randomizer_t *randomizer_create(void)
{
private_randomizer_t *this = allocator_alloc_thing(private_randomizer_t);
/* public functions */
this->public.get_random_bytes = (status_t (*) (randomizer_t *,size_t, u_int8_t *)) get_random_bytes;
this->public.allocate_random_bytes = (status_t (*) (randomizer_t *,size_t, chunk_t *)) allocate_random_bytes;
this->public.get_pseudo_random_bytes = (status_t (*) (randomizer_t *,size_t, u_int8_t *)) get_pseudo_random_bytes;
this->public.allocate_pseudo_random_bytes = (status_t (*) (randomizer_t *,size_t, chunk_t *)) allocate_pseudo_random_bytes;
this->public.destroy = (void (*) (randomizer_t *))destroy;
/* private functions */
this->get_bytes_from_device = get_bytes_from_device;
return &(this->public);
}
|
