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
|
/**
* EGD EntropySource Source File
* (C) 1999-2008 Jack Lloyd
*/
#include <botan/es_egd.h>
#include <botan/bit_ops.h>
#include <botan/parsing.h>
#include <botan/exceptn.h>
#include <cstring>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <unistd.h>
#ifndef PF_LOCAL
#define PF_LOCAL PF_UNIX
#endif
namespace Botan {
EGD_EntropySource::EGD_Socket::EGD_Socket(const std::string& path)
{
m_fd = ::socket(PF_LOCAL, SOCK_STREAM, 0);
if(m_fd > 0)
{
sockaddr_un addr;
std::memset(&addr, 0, sizeof(addr));
addr.sun_family = PF_LOCAL;
if(sizeof(addr.sun_path) < path.length() + 1)
throw Exception("EGD_EntropySource: Socket path is too long");
std::strcpy(addr.sun_path, path.c_str());
int len = sizeof(addr.sun_family) + std::strlen(addr.sun_path) + 1;
if(::connect(m_fd, reinterpret_cast<struct ::sockaddr*>(&addr), len) < 0)
{
::close(m_fd);
m_fd = -1;
}
}
}
void EGD_EntropySource::EGD_Socket::close()
{
if(m_fd > 0)
{
::close(m_fd);
m_fd = -1;
}
}
/**
* EGD_EntropySource constructor
*/
EGD_EntropySource::EGD_EntropySource(const std::vector<std::string>& paths)
{
for(size_t i = 0; i != paths.size(); ++i)
{
EGD_Socket sock(paths[i]);
if(sock.fd() != -1)
sockets.push_back(sock);
}
}
EGD_EntropySource::~EGD_EntropySource()
{
for(size_t i = 0; i != sockets.size(); ++i)
sockets[i].close();
sockets.clear();
}
/**
* Gather Entropy from EGD
*/
u32bit EGD_EntropySource::slow_poll(byte output[], u32bit length)
{
if(length > 128)
length = 128;
for(size_t i = 0; i != sockets.size(); ++i)
{
EGD_Socket& socket = sockets[i];
byte buffer[2];
buffer[0] = 1;
buffer[1] = static_cast<byte>(length);
if(::write(socket.fd(), buffer, 2) != 2)
return 0;
byte out_len = 0;
if(::read(socket.fd(), &out_len, 1) != 1)
return 0;
if(out_len > length)
return 0;
ssize_t count = ::read(socket.fd(), output, out_len);
if(count < 0)
return 0;
return static_cast<u32bit>(count);
}
return 0;
}
/**
* Gather Entropy from EGD, limiting to 64 bytes
*/
u32bit EGD_EntropySource::fast_poll(byte output[], u32bit length)
{
return slow_poll(output, std::min<u32bit>(length, 64));
}
}
|
