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
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
|
#include <iostream>
#include <fcntl.h>
#include <pwd.h>
#include <grp.h>
#include "../datatypes.h"
#include "../log.h"
#include "../signalController.h"
#include "../PracticalSocket.h"
#include "../buffer.h"
#include "options.h"
#include <list>
#define MAX_PACKET_SIZE 1500
class OpenSerHost
{
public:
OpenSerHost() : host_("",0) {};
IfListElement getHost() {
Lock lock(mutex);
return host_;
}
u_int16_t getLocalPort() {
Lock lock(mutex);
return local_port_;
}
void setHost(std::string host, u_int16_t port, u_int16_t local_port)
{
Lock lock(mutex);
if(host_.host_ != host || host_.port_ != port)
cLog.msg(Log::PRIO_NOTICE) << "openSer Host detected at " << host << ":" << port
<< " received at local port " << local_port;
host_.host_ = host;
host_.port_ = port;
local_port_ = local_port;
}
private:
Mutex mutex;
IfListElement host_;
u_int16_t local_port_;
};
struct ThreadParam
{
OpenSerHost& open_ser_;
IfListElement interface_;
};
void* sender(void* p)
{
ThreadParam* param = reinterpret_cast<ThreadParam*>(p);
try
{
UDPSocket recv_sock(param->interface_.host_, param->interface_.port_);
UDPSocket send_sock(gOpt.getSendPort());
IfList remote_host_list(gOpt.getRemoteHosts());
cLog.msg(Log::PRIO_NOTICE) << "sender listening on: " << param->interface_.toString();
Buffer buf(u_int32_t(MAX_PACKET_SIZE));
while(1) {
string remote_host;
u_int16_t remote_port;
buf.setLength(MAX_PACKET_SIZE);
u_int32_t len = recv_sock.recvFrom(buf.getBuf(), buf.getLength(), remote_host, remote_port);
buf.setLength(len);
param->open_ser_.setHost(remote_host, remote_port, param->interface_.port_);
IfList::const_iterator it = remote_host_list.begin();
for(;it != remote_host_list.end(); it++)
send_sock.sendTo(buf.getBuf(), buf.getLength(), it->host_, it->port_);
}
}
catch(std::exception &e)
{
cLog.msg(Log::PRIO_ERR) << "sender(" << param->interface_.toString() << ") exiting because: " << e.what() << std::endl;
}
pthread_exit(NULL);
}
void* receiver(void* p)
{
ThreadParam* param = reinterpret_cast<ThreadParam*>(p);
try
{
UDPSocket recv_sock(gOpt.getSendPort());
UDPSocket send_sock;
u_int16_t local_port = 0;
cLog.msg(Log::PRIO_NOTICE) << "receiver listening for packets from: " << param->interface_.toString();
Buffer buf(u_int32_t(MAX_PACKET_SIZE));
while(1) {
string remote_host;
u_int16_t remote_port;
buf.setLength(MAX_PACKET_SIZE);
u_int32_t len = recv_sock.recvFrom(buf.getBuf(), buf.getLength(), remote_host, remote_port);
buf.setLength(len);
if(remote_host != param->interface_.host_ || remote_port != param->interface_.port_)
continue;
IfListElement openSerHost = param->open_ser_.getHost();
if(openSerHost.host_ == "" || !openSerHost.port_)
{
cLog.msg(Log::PRIO_NOTICE) << "no openser host detected till now, ignoring packet";
continue;
}
if(local_port != param->open_ser_.getLocalPort())
{
local_port = param->open_ser_.getLocalPort();
send_sock.setLocalPort(local_port);
}
send_sock.sendTo(buf.getBuf(), buf.getLength(), openSerHost.host_, openSerHost.port_);
}
}
catch(std::exception &e)
{
cLog.msg(Log::PRIO_ERR) << "sender(" << param->interface_.toString() << ") exiting because: " << e.what() << std::endl;
}
pthread_exit(NULL);
}
void chrootAndDrop(string const& chrootdir, string const& username)
{
if (getuid() != 0)
{
std::cerr << "this programm has to be run as root in order to run in a chroot" << std::endl;
exit(-1);
}
struct passwd *pw = getpwnam(username.c_str());
if(pw) {
if(chroot(chrootdir.c_str()))
{
std::cerr << "can't chroot to " << chrootdir << std::endl;
exit(-1);
}
std::cout << "we are in chroot jail (" << chrootdir << ") now" << std::endl;
chdir("/");
if (initgroups(pw->pw_name, pw->pw_gid) || setgid(pw->pw_gid) || setuid(pw->pw_uid))
{
std::cerr << "can't drop to user " << username << " " << pw->pw_uid << ":" << pw->pw_gid << std::endl;
exit(-1);
}
std::cout << "dropped user to " << username << " " << pw->pw_uid << ":" << pw->pw_gid << std::endl;
}
else
{
std::cerr << "unknown user " << username << std::endl;
exit(-1);
}
}
void daemonize()
{
pid_t pid;
pid = fork();
if(pid) exit(0);
setsid();
pid = fork();
if(pid) exit(0);
std::cout << "running in background now..." << std::endl;
int fd;
for (fd=getdtablesize();fd>=0;--fd) // close all file descriptors
close(fd);
fd=open("/dev/null",O_RDWR); // stdin
dup(fd); // stdout
dup(fd); // stderr
umask(027);
}
int main(int argc, char* argv[])
{
std::cout << "anyrtpproxy" << std::endl;
if(!gOpt.parse(argc, argv))
{
gOpt.printUsage();
exit(-1);
}
if(gOpt.getChroot())
chrootAndDrop(gOpt.getChrootDir(), gOpt.getUsername());
if(gOpt.getDaemonize())
daemonize();
cLog.setLogName("anyrtpproxy");
cLog.msg(Log::PRIO_NOTICE) << "anyrtpproxy started...";
SignalController sig;
sig.init();
OpenSerHost open_ser;
std::list<ThreadParam> params;
IfList listeners(gOpt.getLocalInterfaces());
IfList::iterator it = listeners.begin();
for(;it != listeners.end();++it)
{
ThreadParam param = {open_ser, *it};
params.push_back(param);
pthread_t senderThread;
pthread_create(&senderThread, NULL, sender, &(params.back()));
pthread_detach(senderThread);
}
ThreadParam param = {open_ser, gOpt.getRemoteHosts().front()};
params.push_back(param);
pthread_t receiverThread;
pthread_create(&receiverThread, NULL, receiver, &(params.back()));
pthread_detach(receiverThread);
int ret = sig.run();
return ret;
}
|
