예제 #1
0
파일: Network.cpp 프로젝트: 285452612/bcos
int Network::tcp4Listen(bi::tcp::acceptor& _acceptor, NetworkPreferences const& _netPrefs)
{
	// Due to the complexities of NAT and network environments (multiple NICs, tunnels, etc)
	// and security concerns automation is the enemy of network configuration.
	// If a preference cannot be accommodate the network must fail to start.
	//
	// Preferred IP: Attempt if set, else, try 0.0.0.0 (all interfaces)
	// Preferred Port: Attempt if set, else, try c_defaultListenPort or 0 (random)
	// TODO: throw instead of returning -1 and rename NetworkPreferences to NetworkConfig
	
	bi::address listenIP;
	try
	{
		listenIP = _netPrefs.listenIPAddress.empty() ? bi::address_v4() : bi::address::from_string(_netPrefs.listenIPAddress);
	}
	catch (...)
	{
		LOG(WARNING) << "Couldn't start accepting connections on host. Failed to accept socket on " << listenIP << ":" << _netPrefs.listenPort << ".\n" << boost::current_exception_diagnostic_information();
		return -1;
	}
	bool requirePort = (bool)_netPrefs.listenPort;

	for (unsigned i = 0; i < 2; ++i)
	{
		bi::tcp::endpoint endpoint(listenIP, requirePort ? _netPrefs.listenPort : (i ? 0 : c_defaultListenPort));
		try
		{
#if defined(_WIN32)
			bool reuse = false;
#else
			bool reuse = true;
#endif
			_acceptor.open(endpoint.protocol());
			_acceptor.set_option(ba::socket_base::reuse_address(reuse));
			_acceptor.bind(endpoint);
			_acceptor.listen();
			return _acceptor.local_endpoint().port();
		}
		catch (...)
		{
			// bail if this is first attempt && port was specificed, or second attempt failed (random port)
			if (i || requirePort)
			{
				// both attempts failed
				LOG(WARNING) << "Couldn't start accepting connections on host. Failed to accept socket on " << listenIP << ":" << _netPrefs.listenPort << ".\n" << boost::current_exception_diagnostic_information();
				_acceptor.close();
				return -1;
			}
			
			_acceptor.close();
			continue;
		}
	}

	return -1;
}
예제 #2
0
int Network::tcp4Listen(bi::tcp::acceptor& _acceptor, NetworkPreferences const& _netPrefs)
{
	int retport = -1;
	if (_netPrefs.listenIPAddress.empty())
		for (unsigned i = 0; i < 2; ++i)
		{
			// try to connect w/listenPort, else attempt net-allocated port
			bi::tcp::endpoint endpoint(bi::tcp::v4(), i ? 0 : _netPrefs.listenPort);
			try
			{
				_acceptor.open(endpoint.protocol());
				_acceptor.set_option(ba::socket_base::reuse_address(true));
				_acceptor.bind(endpoint);
				_acceptor.listen();
				retport = _acceptor.local_endpoint().port();
				break;
			}
			catch (...)
			{
				if (i)
				{
					// both attempts failed
					cwarn << "Couldn't start accepting connections on host. Something very wrong with network?\n" << boost::current_exception_diagnostic_information();
				}
				
				// first attempt failed
				_acceptor.close();
				continue;
			}
		}
	else
	{
		bi::tcp::endpoint endpoint(bi::address::from_string(_netPrefs.listenIPAddress), _netPrefs.listenPort);
		try
		{
			_acceptor.open(endpoint.protocol());
			_acceptor.set_option(ba::socket_base::reuse_address(true));
			_acceptor.bind(endpoint);
			_acceptor.listen();
			retport = _acceptor.local_endpoint().port();
			assert(retport == _netPrefs.listenPort);
		}
		catch (...)
		{
			clog(NetWarn) << "Couldn't start accepting connections on host. Failed to accept socket.\n" << boost::current_exception_diagnostic_information();
		}
		return retport;
	}
	return retport;
}