private Task ConnectAsyncCore(IPAddress[] addresses, int port)
{
// Validate the args, similar to how Socket.Connect(IPAddress[], int) would.
if (addresses == null)
{
throw new ArgumentNullException(nameof(addresses));
}
if (addresses.Length == 0)
{
throw new ArgumentException(SR.net_invalidAddressList, nameof(addresses));
}
if (!TcpValidationHelpers.ValidatePortNumber(port))
{
throw new ArgumentOutOfRangeException(nameof(port));
}
// If the client socket has already materialized, this API can't be used.
// Similarly if another operation to set the socket is already in progress.
if (_clientSocket != null)
{
throw new PlatformNotSupportedException(SR.net_sockets_connect_multiaddress_notsupported);
}
// Do the real work.
EnterClientLock();
return(ConnectAsyncCorePrivate(addresses, port));
}
// This creates a TcpListener that listens on both IPv4 and IPv6 on the given port.
public static TcpListener Create(int port)
{
if (NetEventSource.IsEnabled)
{
NetEventSource.Enter(null, port);
}
if (!TcpValidationHelpers.ValidatePortNumber(port))
{
throw new ArgumentOutOfRangeException(nameof(port));
}
TcpListener listener;
if (Socket.OSSupportsIPv6)
{
// If OS supports IPv6 use dual mode so both address families work.
listener = new TcpListener(IPAddress.IPv6Any, port);
listener.Server.DualMode = true;
}
else
{
// If not, fall-back to old IPv4.
listener = new TcpListener(IPAddress.Any, port);
}
if (NetEventSource.IsEnabled)
{
NetEventSource.Exit(null, port);
}
return(listener);
}
// Connects the Client to the specified port on the specified host.
public void Connect(IPAddress address, int port)
{
if (Logging.On)
{
Logging.Enter(Logging.Sockets, this, "Connect", address);
}
if (_cleanedUp)
{
throw new ObjectDisposedException(this.GetType().FullName);
}
if (address == null)
{
throw new ArgumentNullException("address");
}
if (!TcpValidationHelpers.ValidatePortNumber(port))
{
throw new ArgumentOutOfRangeException("port");
}
IPEndPoint remoteEP = new IPEndPoint(address, port);
Connect(remoteEP);
if (Logging.On)
{
Logging.Exit(Logging.Sockets, this, "Connect", null);
}
}
// Connects the Client to the specified port on the specified host.
public void Connect(IPAddress address, int port)
{
if (NetEventSource.Log.IsEnabled())
{
NetEventSource.Enter(this, address);
}
ThrowIfDisposed();
if (address == null)
{
throw new ArgumentNullException(nameof(address));
}
if (!TcpValidationHelpers.ValidatePortNumber(port))
{
throw new ArgumentOutOfRangeException(nameof(port));
}
IPEndPoint remoteEP = new IPEndPoint(address, port);
Connect(remoteEP);
if (NetEventSource.Log.IsEnabled())
{
NetEventSource.Exit(this);
}
}
// Connects the Client to the specified port on the specified host.
public void Connect(IPAddress address, int port)
{
if (NetEventSource.IsEnabled)
{
NetEventSource.Enter(this, address);
}
if (_cleanedUp)
{
throw new ObjectDisposedException(GetType().FullName);
}
if (address == null)
{
throw new ArgumentNullException(nameof(address));
}
if (!TcpValidationHelpers.ValidatePortNumber(port))
{
throw new ArgumentOutOfRangeException(nameof(port));
}
IPEndPoint remoteEP = new IPEndPoint(address, port);
Connect(remoteEP);
if (NetEventSource.IsEnabled)
{
NetEventSource.Exit(this);
}
}
// Initializes a new instance of the System.Net.Sockets.TcpClient class and connects to the specified port on
// the specified host.
public TcpClient(string hostname, int port)
{
if (NetEventSource.IsEnabled)
{
NetEventSource.Enter(this, hostname);
}
if (hostname == null)
{
throw new ArgumentNullException(nameof(hostname));
}
if (!TcpValidationHelpers.ValidatePortNumber(port))
{
throw new ArgumentOutOfRangeException(nameof(port));
}
try
{
Connect(hostname, port);
}
catch
{
_clientSocket?.Close();
throw;
}
if (NetEventSource.IsEnabled)
{
NetEventSource.Exit(this);
}
}
// Initializes a new instance of the System.Net.Sockets.TcpClient class and connects to the specified port on
// the specified host.
public TcpClient(string hostname, int port)
{
if (NetEventSource.Log.IsEnabled())
{
NetEventSource.Info(this, hostname);
}
if (hostname == null)
{
throw new ArgumentNullException(nameof(hostname));
}
if (!TcpValidationHelpers.ValidatePortNumber(port))
{
throw new ArgumentOutOfRangeException(nameof(port));
}
_family = AddressFamily.Unknown;
try
{
Connect(hostname, port);
}
catch
{
_clientSocket?.Close();
throw;
}
}
// Creates a new instance of the UdpClient class that communicates on the
// specified port number.
public UdpClient(int port, AddressFamily family)
{
// Validate input parameters.
if (!TcpValidationHelpers.ValidatePortNumber(port))
{
throw new ArgumentOutOfRangeException(nameof(port));
}
// Validate the address family.
if (family != AddressFamily.InterNetwork && family != AddressFamily.InterNetworkV6)
{
throw new ArgumentException(SR.Format(SR.net_protocol_invalid_family, "UDP"), nameof(family));
}
IPEndPoint localEP;
_family = family;
if (_family == AddressFamily.InterNetwork)
{
localEP = new IPEndPoint(IPAddress.Any, port);
}
else
{
localEP = new IPEndPoint(IPAddress.IPv6Any, port);
}
CreateClientSocket();
_clientSocket.Bind(localEP);
}
public TcpListener(int port)
{
if (!TcpValidationHelpers.ValidatePortNumber(port))
{
throw new ArgumentOutOfRangeException(nameof(port));
}
_serverSocketEP = new IPEndPoint(IPAddress.Any, port);
_serverSocket = new Socket(_serverSocketEP.AddressFamily, SocketType.Stream, ProtocolType.Tcp);
}
// Connects the Client to the specified port on the specified host.
public void Connect(IPAddress address, int port)
{
ThrowIfDisposed();
ArgumentNullException.ThrowIfNull(address);
if (!TcpValidationHelpers.ValidatePortNumber(port))
{
throw new ArgumentOutOfRangeException(nameof(port));
}
IPEndPoint remoteEP = new IPEndPoint(address, port);
Connect(remoteEP);
}
// Connects the Client to the specified port on the specified host.
public void Connect(string hostname, int port)
{
ThrowIfDisposed();
ArgumentNullException.ThrowIfNull(hostname);
if (!TcpValidationHelpers.ValidatePortNumber(port))
{
throw new ArgumentOutOfRangeException(nameof(port));
}
Client.Connect(hostname, port);
_family = Client.AddressFamily;
_active = true;
}
public UdpClient(string hostname, int port)
{
ArgumentNullException.ThrowIfNull(hostname);
if (!TcpValidationHelpers.ValidatePortNumber(port))
{
throw new ArgumentOutOfRangeException(nameof(port));
}
// NOTE: Need to create different kinds of sockets based on the addresses
// returned from DNS. As a result, we defer the creation of the
// socket until the Connect method.
Connect(hostname, port);
}
// Initializes a new instance of the TcpListener class that listens to the specified IP address
// and port.
public TcpListener(IPAddress localaddr, int port)
{
if (NetEventSource.Log.IsEnabled())
{
NetEventSource.Info(this, localaddr);
}
ArgumentNullException.ThrowIfNull(localaddr);
if (!TcpValidationHelpers.ValidatePortNumber(port))
{
throw new ArgumentOutOfRangeException(nameof(port));
}
_serverSocketEP = new IPEndPoint(localaddr, port);
_serverSocket = new Socket(_serverSocketEP.AddressFamily, SocketType.Stream, ProtocolType.Tcp);
}
public void Connect(IPAddress addr, int port)
{
ThrowIfDisposed();
if (addr == null)
{
throw new ArgumentNullException(nameof(addr));
}
if (!TcpValidationHelpers.ValidatePortNumber(port))
{
throw new ArgumentOutOfRangeException(nameof(port));
}
IPEndPoint endPoint = new IPEndPoint(addr, port);
Connect(endPoint);
}
public void Connect(IPAddress addr, int port)
{
if (_cleanedUp)
{
throw new ObjectDisposedException(this.GetType().FullName);
}
if (addr == null)
{
throw new ArgumentNullException(nameof(addr));
}
if (!TcpValidationHelpers.ValidatePortNumber(port))
{
throw new ArgumentOutOfRangeException(nameof(port));
}
IPEndPoint endPoint = new IPEndPoint(addr, port);
Connect(endPoint);
}
// Initializes a new instance of the System.Net.Sockets.TcpClient class and connects to the
// specified port on the specified host.
public TcpClient(string hostname, int port)
{
if (Logging.On)
{
Logging.Enter(Logging.Sockets, this, "TcpClient", hostname);
}
if (hostname == null)
{
throw new ArgumentNullException("hostname");
}
if (!TcpValidationHelpers.ValidatePortNumber(port))
{
throw new ArgumentOutOfRangeException("port");
}
// IPv6: Delay creating the client socket until we have
// performed DNS resolution and know which address
// families we can use.
try
{
Connect(hostname, port);
}
catch (Exception e)
{
if (e is OutOfMemoryException)
{
throw;
}
if (_clientSocket != null)
{
_clientSocket.Dispose();
}
throw e;
}
if (Logging.On)
{
Logging.Exit(Logging.Sockets, this, "TcpClient", null);
}
}
private void StartConnectCore(string host, int port)
{
// Validate the args, similar to how Socket.Connect(string, int) would.
if (host == null)
{
throw new ArgumentNullException(nameof(host));
}
if (!TcpValidationHelpers.ValidatePortNumber(port))
{
throw new ArgumentOutOfRangeException(nameof(port));
}
// If the client socket has already materialized, this API can't be used.
if (_clientSocket != null)
{
throw new PlatformNotSupportedException(SR.net_sockets_connect_multiaddress_notsupported);
}
EnterClientLock();
}
// Initializes a new instance of the System.Net.Sockets.TcpClient class and connects to the specified port on
// the specified host.
public TcpClient(string hostname, int port)
{
if (NetEventSource.Log.IsEnabled())
{
NetEventSource.Enter(NetEventSource.ComponentType.Socket, this, nameof(TcpClient), hostname);
}
if (hostname == null)
{
throw new ArgumentNullException(nameof(hostname));
}
if (!TcpValidationHelpers.ValidatePortNumber(port))
{
throw new ArgumentOutOfRangeException(nameof(port));
}
// IPv6: Delay creating the client socket until we have
// performed DNS resolution and know which address
// families we can use.
try
{
Connect(hostname, port);
}
catch
{
if (_clientSocket != null)
{
_clientSocket.Close();
}
throw;
}
if (NetEventSource.Log.IsEnabled())
{
NetEventSource.Exit(NetEventSource.ComponentType.Socket, this, nameof(TcpClient), null);
}
}
// This creates a TcpListener that listens on both IPv4 and IPv6 on the given port.
public static TcpListener Create(int port)
{
if (Logging.On)
{
Logging.Enter(Logging.Sockets, "TcpListener.Create", "Port: " + port);
}
if (!TcpValidationHelpers.ValidatePortNumber(port))
{
throw new ArgumentOutOfRangeException("port");
}
TcpListener listener = new TcpListener(IPAddress.IPv6Any, port);
listener.Server.DualMode = true;
if (Logging.On)
{
Logging.Exit(Logging.Sockets, "TcpListener.Create", "Port: " + port);
}
return(listener);
}
// Establishes a connection with the host at the specified address on the
// specified port.
public void Connect(IPAddress addr, int port)
{
// Validate input parameters.
if (_cleanedUp)
{
throw new ObjectDisposedException(this.GetType().FullName);
}
if (addr == null)
{
throw new ArgumentNullException("addr");
}
if (!TcpValidationHelpers.ValidatePortNumber(port))
{
throw new ArgumentOutOfRangeException("port");
}
// IPv6 Changes: Removed redundant call to CheckForBroadcast() since
// it is made in the real Connect() method.
IPEndPoint endPoint = new IPEndPoint(addr, port);
Connect(endPoint);
}
// Initializes a new instance of the TcpListener class that listens to the specified IP address
// and port.
public TcpListener(IPAddress localaddr, int port)
{
if (NetEventSource.Log.IsEnabled())
{
NetEventSource.Enter(NetEventSource.ComponentType.Socket, this, "TcpListener", localaddr);
}
if (localaddr == null)
{
throw new ArgumentNullException(nameof(localaddr));
}
if (!TcpValidationHelpers.ValidatePortNumber(port))
{
throw new ArgumentOutOfRangeException(nameof(port));
}
_serverSocketEP = new IPEndPoint(localaddr, port);
_serverSocket = new Socket(_serverSocketEP.AddressFamily, SocketType.Stream, ProtocolType.Tcp);
if (NetEventSource.Log.IsEnabled())
{
NetEventSource.Exit(NetEventSource.ComponentType.Socket, this, "TcpListener", null);
}
}
// Initializes a new instance of the TcpListener class that listens to the specified IP address
// and port.
public TcpListener(IPAddress localaddr, int port)
{
if (Logging.On)
{
Logging.Enter(Logging.Sockets, this, "TcpListener", localaddr);
}
if (localaddr == null)
{
throw new ArgumentNullException("localaddr");
}
if (!TcpValidationHelpers.ValidatePortNumber(port))
{
throw new ArgumentOutOfRangeException("port");
}
_serverSocketEP = new IPEndPoint(localaddr, port);
_serverSocket = new Socket(_serverSocketEP.AddressFamily, SocketType.Stream, ProtocolType.Tcp);
if (Logging.On)
{
Logging.Exit(Logging.Sockets, this, "TcpListener", null);
}
}
// This creates a TcpListener that listens on both IPv4 and IPv6 on the given port.
public static TcpListener Create(int port)
{
if (NetEventSource.IsEnabled)
{
NetEventSource.Enter(null, port);
}
if (!TcpValidationHelpers.ValidatePortNumber(port))
{
throw new ArgumentOutOfRangeException(nameof(port));
}
TcpListener listener = new TcpListener(IPAddress.IPv6Any, port);
listener.Server.DualMode = true;
if (NetEventSource.IsEnabled)
{
NetEventSource.Exit(null, port);
}
return(listener);
}
// This creates a TcpListener that listens on both IPv4 and IPv6 on the given port.
public static TcpListener Create(int port)
{
if (NetEventSource.Log.IsEnabled())
{
NetEventSource.Enter(NetEventSource.ComponentType.Socket, "TcpListener.Create", "Port: " + port, null);
}
if (!TcpValidationHelpers.ValidatePortNumber(port))
{
throw new ArgumentOutOfRangeException(nameof(port));
}
TcpListener listener = new TcpListener(IPAddress.IPv6Any, port);
listener.Server.DualMode = true;
if (NetEventSource.Log.IsEnabled())
{
NetEventSource.Exit(NetEventSource.ComponentType.Socket, "TcpListener.Create", "Port: " + port, null);
}
return(listener);
}
// Connects the Client to the specified port on the specified host.
public void Connect(string hostname, int port)
{
if (NetEventSource.Log.IsEnabled())
{
NetEventSource.Enter(NetEventSource.ComponentType.Socket, this, nameof(Connect), hostname);
}
if (_cleanedUp)
{
throw new ObjectDisposedException(this.GetType().FullName);
}
if (hostname == null)
{
throw new ArgumentNullException(nameof(hostname));
}
if (!TcpValidationHelpers.ValidatePortNumber(port))
{
throw new ArgumentOutOfRangeException(nameof(port));
}
// Check for already connected and throw here. This check
// is not required in the other connect methods as they
// will throw from WinSock. Here, the situation is more
// complex since we have to resolve a hostname so it's
// easier to simply block the request up front.
if (_active)
{
throw new SocketException((int)SocketError.IsConnected);
}
ConnectCore(hostname, port);
if (NetEventSource.Log.IsEnabled())
{
NetEventSource.Exit(NetEventSource.ComponentType.Socket, this, nameof(Connect), null);
}
}
public void Connect(string hostname, int port)
{
ThrowIfDisposed();
if (hostname == null)
{
throw new ArgumentNullException(nameof(hostname));
}
if (!TcpValidationHelpers.ValidatePortNumber(port))
{
throw new ArgumentOutOfRangeException(nameof(port));
}
// We must now look for addresses that use a compatible address family to the client socket. However, in the
// case of the <hostname,port> constructor we will have deferred creating the socket and will do that here
// instead.
IPAddress[] addresses = Dns.GetHostAddresses(hostname);
Exception lastex = null;
Socket ipv6Socket = null;
Socket ipv4Socket = null;
try
{
if (_clientSocket == null)
{
if (Socket.OSSupportsIPv4)
{
ipv4Socket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
}
if (Socket.OSSupportsIPv6)
{
ipv6Socket = new Socket(AddressFamily.InterNetworkV6, SocketType.Dgram, ProtocolType.Udp);
}
}
foreach (IPAddress address in addresses)
{
try
{
if (_clientSocket == null)
{
// We came via the <hostname,port> constructor. Set the
// address family appropriately, create the socket and
// try to connect.
if (address.AddressFamily == AddressFamily.InterNetwork && ipv4Socket != null)
{
ipv4Socket.Connect(address, port);
_clientSocket = ipv4Socket;
if (ipv6Socket != null)
{
ipv6Socket.Close();
}
}
else if (ipv6Socket != null)
{
ipv6Socket.Connect(address, port);
_clientSocket = ipv6Socket;
if (ipv4Socket != null)
{
ipv4Socket.Close();
}
}
_family = address.AddressFamily;
_active = true;
break;
}
else if (IsAddressFamilyCompatible(address.AddressFamily))
{
// Only use addresses with a matching family
Connect(new IPEndPoint(address, port));
_active = true;
break;
}
}
catch (Exception ex)
{
if (ExceptionCheck.IsFatal(ex))
{
throw;
}
lastex = ex;
}
}
}
catch (Exception ex)
{
if (ExceptionCheck.IsFatal(ex))
{
throw;
}
lastex = ex;
}
finally
{
//cleanup temp sockets if failed
//main socket gets closed when tcpclient gets closed
//did we connect?
if (!_active)
{
if (ipv6Socket != null)
{
ipv6Socket.Close();
}
if (ipv4Socket != null)
{
ipv4Socket.Close();
}
// The connect failed - rethrow the last error we had
if (lastex != null)
{
throw lastex;
}
else
{
throw new SocketException((int)SocketError.NotConnected);
}
}
}
}
// Connects the Client to the specified port on the specified host.
public void Connect(string hostname, int port)
{
if (Logging.On)
{
Logging.Enter(Logging.Sockets, this, "Connect", hostname);
}
if (_cleanedUp)
{
throw new ObjectDisposedException(this.GetType().FullName);
}
if (hostname == null)
{
throw new ArgumentNullException("hostname");
}
if (!TcpValidationHelpers.ValidatePortNumber(port))
{
throw new ArgumentOutOfRangeException("port");
}
// Check for already connected and throw here. This check
// is not required in the other connect methods as they
// will throw from WinSock. Here, the situation is more
// complex since we have to resolve a hostname so it's
// easier to simply block the request up front.
if (_active)
{
throw new SocketException((int)SocketError.IsConnected);
}
// IPv6: We need to process each of the addresses return from
// DNS when trying to connect. Use of AddressList[0] is
// bad form.
IPAddress[] addresses = Dns.GetHostAddressesAsync(hostname).GetAwaiter().GetResult();
Exception lastex = null;
Socket ipv6Socket = null;
Socket ipv4Socket = null;
try
{
if (_clientSocket == null)
{
if (Socket.OSSupportsIPv4)
{
ipv4Socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
}
if (Socket.OSSupportsIPv6)
{
ipv6Socket = new Socket(AddressFamily.InterNetworkV6, SocketType.Stream, ProtocolType.Tcp);
}
}
foreach (IPAddress address in addresses)
{
try
{
if (_clientSocket == null)
{
// We came via the <hostname,port> constructor. Set the
// address family appropriately, create the socket and
// try to connect.
if (address.AddressFamily == AddressFamily.InterNetwork && ipv4Socket != null)
{
ipv4Socket.Connect(address, port);
_clientSocket = ipv4Socket;
if (ipv6Socket != null)
{
ipv6Socket.Dispose();
}
}
else if (ipv6Socket != null)
{
ipv6Socket.Connect(address, port);
_clientSocket = ipv6Socket;
if (ipv4Socket != null)
{
ipv4Socket.Dispose();
}
}
_family = address.AddressFamily;
_active = true;
break;
}
else if (address.AddressFamily == _family)
{
// Only use addresses with a matching family.
Connect(new IPEndPoint(address, port));
_active = true;
break;
}
}
catch (Exception ex)
{
if (ex is OutOfMemoryException)
{
throw;
}
lastex = ex;
}
}
}
catch (Exception ex)
{
if (ex is OutOfMemoryException)
{
throw;
}
lastex = ex;
}
finally
{
// Cleanup temp sockets if failed. Main socket gets closed when TCPClient gets closed.
// Did we connect?
if (!_active)
{
if (ipv6Socket != null)
{
ipv6Socket.Dispose();
}
if (ipv4Socket != null)
{
ipv4Socket.Dispose();
}
// The connect failed - rethrow the last error we had.
if (lastex != null)
{
throw lastex;
}
else
{
throw new SocketException((int)SocketError.NotConnected);
}
}
}
if (Logging.On)
{
Logging.Exit(Logging.Sockets, this, "Connect", null);
}
}
// Connects the Client to the specified port on the specified host.
public void Connect(string hostname, int port)
{
if (NetEventSource.IsEnabled)
{
NetEventSource.Enter(this, hostname);
}
if (_cleanedUp)
{
throw new ObjectDisposedException(GetType().FullName);
}
if (hostname == null)
{
throw new ArgumentNullException(nameof(hostname));
}
if (!TcpValidationHelpers.ValidatePortNumber(port))
{
throw new ArgumentOutOfRangeException(nameof(port));
}
// Check for already connected and throw here. This check
// is not required in the other connect methods as they
// will throw from WinSock. Here, the situation is more
// complex since we have to resolve a hostname so it's
// easier to simply block the request up front.
if (_active)
{
throw new SocketException((int)SocketError.IsConnected);
}
// IPv6: We need to process each of the addresses returned from
// DNS when trying to connect. Use of AddressList[0] is
// bad form.
IPAddress[] addresses = Dns.GetHostAddresses(hostname);
ExceptionDispatchInfo lastex = null;
try
{
foreach (IPAddress address in addresses)
{
Socket tmpSocket = null;
try
{
if (_clientSocket == null)
{
// We came via the <hostname,port> constructor. Set the address family appropriately,
// create the socket and try to connect.
Debug.Assert(address.AddressFamily == AddressFamily.InterNetwork || address.AddressFamily == AddressFamily.InterNetworkV6);
if ((address.AddressFamily == AddressFamily.InterNetwork && Socket.OSSupportsIPv4) || Socket.OSSupportsIPv6)
{
tmpSocket = new Socket(address.AddressFamily, SocketType.Stream, ProtocolType.Tcp);
tmpSocket.Connect(address, port);
_clientSocket = tmpSocket;
tmpSocket = null;
}
_family = address.AddressFamily;
_active = true;
break;
}
else if (address.AddressFamily == _family || _family == AddressFamily.Unknown)
{
// Only use addresses with a matching family
Connect(new IPEndPoint(address, port));
_active = true;
break;
}
}
catch (Exception ex) when(!(ex is OutOfMemoryException))
{
if (tmpSocket != null)
{
tmpSocket.Dispose();
tmpSocket = null;
}
lastex = ExceptionDispatchInfo.Capture(ex);
}
}
}
finally
{
if (!_active)
{
// The connect failed - rethrow the last error we had
lastex?.Throw();
throw new SocketException((int)SocketError.NotConnected);
}
}
if (NetEventSource.IsEnabled)
{
NetEventSource.Exit(this);
}
}
// Establishes a connection to the specified port on the specified host.
public void Connect(string hostname, int port)
{
// Validate input parameters.
if (_cleanedUp)
{
throw new ObjectDisposedException(this.GetType().FullName);
}
if (hostname == null)
{
throw new ArgumentNullException("hostname");
}
if (!TcpValidationHelpers.ValidatePortNumber(port))
{
throw new ArgumentOutOfRangeException("port");
}
// IPv6 Changes: instead of just using the first address in the list,
// we must now look for addresses that use a compatible
// address family to the client socket.
// However, in the case of the <hostname,port> constructor
// we will have deferred creating the socket and will
// do that here instead.
// In addition, the redundant CheckForBroadcast call was
// removed here since it is called from Connect().
IPAddress[] addresses = Dns.GetHostAddressesAsync(hostname).GetAwaiter().GetResult();
Exception lastex = null;
Socket ipv6Socket = null;
Socket ipv4Socket = null;
try
{
if (_clientSocket == null)
{
if (Socket.OSSupportsIPv4)
{
ipv4Socket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
}
if (Socket.OSSupportsIPv6)
{
ipv6Socket = new Socket(AddressFamily.InterNetworkV6, SocketType.Dgram, ProtocolType.Udp);
}
}
foreach (IPAddress address in addresses)
{
try
{
if (_clientSocket == null)
{
// We came via the <hostname,port> constructor. Set the
// address family appropriately, create the socket and
// try to connect.
if (address.AddressFamily == AddressFamily.InterNetwork && ipv4Socket != null)
{
ipv4Socket.Connect(address, port);
_clientSocket = ipv4Socket;
if (ipv6Socket != null)
{
ipv6Socket.Dispose();
}
}
else if (ipv6Socket != null)
{
ipv6Socket.Connect(address, port);
_clientSocket = ipv6Socket;
if (ipv4Socket != null)
{
ipv4Socket.Dispose();
}
}
_family = address.AddressFamily;
_active = true;
break;
}
else if (address.AddressFamily == _family)
{
// Only use addresses with a matching family.
Connect(new IPEndPoint(address, port));
_active = true;
break;
}
}
catch (Exception ex)
{
if (ExceptionCheck.IsFatal(ex))
{
throw;
}
lastex = ex;
}
}
}
catch (Exception ex)
{
if (ExceptionCheck.IsFatal(ex))
{
throw;
}
lastex = ex;
}
finally
{
// Cleanup temp sockets on failure. The main socket gets closed when the UDPClient
// gets closed.
// Did we connect?
if (!_active)
{
if (ipv6Socket != null)
{
ipv6Socket.Dispose();
}
if (ipv4Socket != null)
{
ipv4Socket.Dispose();
}
// The connect failed - rethrow the last error we had.
if (lastex != null)
{
throw lastex;
}
else
{
throw new SocketException((int)SocketError.NotConnected);
}
}
}
}
// Connects the Client to the specified port on the specified host.
public void Connect(string hostname, int port)
{
ThrowIfDisposed();
ArgumentNullException.ThrowIfNull(hostname);
if (!TcpValidationHelpers.ValidatePortNumber(port))
{
throw new ArgumentOutOfRangeException(nameof(port));
}
// Check for already connected and throw here. This check
// is not required in the other connect methods as they
// will throw from WinSock. Here, the situation is more
// complex since we have to resolve a hostname so it's
// easier to simply block the request up front.
if (_active)
{
throw new SocketException((int)SocketError.IsConnected);
}
// IPv6: We need to process each of the addresses returned from
// DNS when trying to connect. Use of AddressList[0] is
// bad form.
IPAddress[] addresses = Dns.GetHostAddresses(hostname);
ExceptionDispatchInfo?lastex = null;
try
{
foreach (IPAddress address in addresses)
{
try
{
if (_clientSocket == null)
{
// We came via the <hostname,port> constructor. Set the address family appropriately,
// create the socket and try to connect.
Debug.Assert(address.AddressFamily == AddressFamily.InterNetwork || address.AddressFamily == AddressFamily.InterNetworkV6);
if ((address.AddressFamily == AddressFamily.InterNetwork && Socket.OSSupportsIPv4) || Socket.OSSupportsIPv6)
{
var socket = new Socket(address.AddressFamily, SocketType.Stream, ProtocolType.Tcp);
if (address.IsIPv4MappedToIPv6)
{
socket.DualMode = true;
}
// Use of Interlocked.Exchanged ensures _clientSocket is written before Disposed is read.
Interlocked.Exchange(ref _clientSocket !, socket);
if (Disposed)
{
// Dispose the socket so it throws ObjectDisposedException when we Connect.
socket.Dispose();
}
try
{
socket.Connect(address, port);
}
catch
{
_clientSocket = null !;
throw;
}
}
_family = address.AddressFamily;
_active = true;
break;
}
else if (address.AddressFamily == _family || _family == AddressFamily.Unknown)
{
// Only use addresses with a matching family
Connect(new IPEndPoint(address, port));
_active = true;
break;
}
}
catch (Exception ex) when(!(ex is OutOfMemoryException))
{
lastex = ExceptionDispatchInfo.Capture(ex);
}
}
}
finally
{
if (!_active)
{
// The connect failed - rethrow the last error we had
lastex?.Throw();
throw new SocketException((int)SocketError.NotConnected);
}
}
}
