blob: 2f0287c86dd0bddffdca417c7bca952c214d1e8b (
plain)
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
|
/*
Mosh: the mobile shell
Copyright 2012 Keith Winstein
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 3 of the License, or
(at your option) any later version.
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.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef PRNG_HPP
#define PRNG_HPP
#include <string>
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <stdint.h>
#include "crypto.h"
/* Read random bytes from /dev/urandom.
We rely on stdio buffering for efficiency. */
static const char rdev[] = "/dev/urandom";
using namespace Crypto;
class PRNG {
private:
FILE *randfile;
/* unimplemented to satisfy -Weffc++ */
PRNG( const PRNG & );
PRNG & operator=( const PRNG & );
public:
PRNG() : randfile( fopen( rdev, "rb" ) )
{
if ( randfile == NULL ) {
throw CryptoException( std::string( rdev ) + ": " + strerror( errno ) );
}
}
~PRNG() {
if ( 0 != fclose( randfile ) ) {
throw CryptoException( std::string( rdev ) + ": " + strerror( errno ) );
}
}
void fill( void *dest, size_t size ) {
if ( 0 == size ) {
return;
}
if ( 1 != fread( dest, size, 1, randfile ) ) {
throw CryptoException( "Could not read from " + std::string( rdev ) );
}
}
uint8_t uint8() {
uint8_t x;
fill( &x, 1 );
return x;
}
uint32_t uint32() {
uint32_t x;
fill( &x, 4 );
return x;
}
uint64_t uint64() {
uint64_t x;
fill( &x, 8 );
return x;
}
};
#endif
|
