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#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_;
}
void setHost(std::string host, u_int16_t port)
{
Lock lock(mutex);
if(host_.host_ != host || host_.port_ != port)
cLog.msg(Log::PRIO_NOTICE) << "openSer Host detected at " << host << ":" << port;
host_.host_ = host;
host_.port_ = port;
}
private:
Mutex mutex;
IfListElement host_;
};
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);
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 sock(gOpt.getSendPort());
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 = 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;
}
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;
}
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