/// <summary>
/// Performs a connection handshake with the remote end of the connection.
/// Exchanges network identifier and any listener whose IPAddress matches the connection localEndPoint IPAddress.
/// </summary>
protected void ConnectionHandshake()
{
if (ConnectionInfo.ApplicationLayerProtocol == ApplicationLayerProtocolStatus.Disabled)
{
throw new CommunicationException("Attempted to perform handshake on connection where the application protocol has been disabled.");
}
//If we are server side and we have just received an incoming connection we need to return a connection identifier
//This id will be used in all future connections from this machine
if (ConnectionInfo.ServerSide)
{
if (NetworkComms.LoggingEnabled)
{
NetworkComms.Logger.Debug("Waiting for client connnectionInfo from " + ConnectionInfo);
}
//Wait for the client to send its identification
#if NET2
if (!connectionSetupWait.WaitOne(NetworkComms.ConnectionEstablishTimeoutMS, false))
#else
if (!connectionSetupWait.WaitOne(NetworkComms.ConnectionEstablishTimeoutMS))
#endif
{ throw new ConnectionSetupException("Timeout waiting for client connectionInfo with " + ConnectionInfo + ". Connection created at " + ConnectionInfo.ConnectionCreationTime.ToString("HH:mm:ss.fff") + ", its now " + DateTime.Now.ToString("HH:mm:ss.f")); }
if (connectionSetupException)
{
if (NetworkComms.LoggingEnabled)
{
NetworkComms.Logger.Debug("Connection setup exception. ServerSide with " + ConnectionInfo + ", " + connectionSetupExceptionStr);
}
throw new ConnectionSetupException("ServerSide. " + connectionSetupExceptionStr);
}
//Trigger the connection establish delegates before replying to the connection establish
TriggerConnectionEstablishDelegates();
}
else
{
//If we are client side part of the handshake is to inform the server of a potential local listener
//Get a list of existing listeners
List <EndPoint> existingLocalListeners = null;
if (ConnectionInfo.LocalEndPoint is IPEndPoint)
{
existingLocalListeners = Connection.ExistingLocalListenEndPoints(ConnectionInfo.ConnectionType, new IPEndPoint(ConnectionInfo.LocalIPEndPoint.Address, 0));
}
#if NET4 || NET35
else if (ConnectionInfo.LocalEndPoint is InTheHand.Net.BluetoothEndPoint)
{
existingLocalListeners = Connection.ExistingLocalListenEndPoints(ConnectionInfo.ConnectionType, new InTheHand.Net.BluetoothEndPoint(ConnectionInfo.LocalBTEndPoint.Address, ConnectionInfo.LocalBTEndPoint.Service));
}
#endif
//Check to see if we have a local listener for matching the local endpoint address
//If we are client side we use this local listener in our reply to the server
EndPoint selectedExistingLocalListenerEndPoint = null;
if (existingLocalListeners != null && // If we have a suitable local listener
existingLocalListeners.Count > 0 && // If we have a suitable local listener
!existingLocalListeners.Contains(ConnectionInfo.RemoteEndPoint)) //If this is not an application loop back connection
{
selectedExistingLocalListenerEndPoint = (existingLocalListeners.Contains(ConnectionInfo.LocalEndPoint) ? ConnectionInfo.LocalEndPoint : existingLocalListeners[0]);
}
//During this exchange we may note an update local listen port
if (NetworkComms.LoggingEnabled)
{
NetworkComms.Logger.Debug("Sending connnectionInfo to " + ConnectionInfo);
}
//Pull-out the parameters we want to send to the server
//Doing it here rather than all in the following Send Object line keeps it clearer
EndPoint selectedLocalListenerEndPoint = (selectedExistingLocalListenerEndPoint != null ? selectedExistingLocalListenerEndPoint : ConnectionInfo.LocalEndPoint);
bool connectable = selectedExistingLocalListenerEndPoint != null;
//As the client we initiated the connection we now forward our local node identifier to the server
//If we are listening we include our local listen port as well
SendObject(Enum.GetName(typeof(ReservedPacketType), ReservedPacketType.ConnectionSetup), new ConnectionInfo(ConnectionInfo.ConnectionType,
NetworkComms.NetworkIdentifier,
selectedLocalListenerEndPoint,
connectable),
NetworkComms.InternalFixedSendReceiveOptions);
//Wait here for the server end to return its own identifier
#if NET2
if (!connectionSetupWait.WaitOne(NetworkComms.ConnectionEstablishTimeoutMS, false))
#else
if (!connectionSetupWait.WaitOne(NetworkComms.ConnectionEstablishTimeoutMS))
#endif
{ throw new ConnectionSetupException("Timeout waiting for server connnectionInfo from " + ConnectionInfo + ". Connection created at " + ConnectionInfo.ConnectionCreationTime.ToString("HH:mm:ss.fff") + ", its now " + DateTime.Now.ToString("HH:mm:ss.f")); }
//If we are client side we can update the localEndPoint for this connection to reflect what the remote end might see if we are also listening
if (selectedExistingLocalListenerEndPoint != null && selectedExistingLocalListenerEndPoint != ConnectionInfo.LocalEndPoint)
{
//We should now be able to set the connectionInfo localEndPoint
NetworkComms.UpdateConnectionReferenceByEndPoint(this, ConnectionInfo.RemoteEndPoint, selectedExistingLocalListenerEndPoint);
ConnectionInfo.UpdateLocalEndPointInfo(selectedExistingLocalListenerEndPoint);
}
if (connectionSetupException)
{
if (NetworkComms.LoggingEnabled)
{
NetworkComms.Logger.Debug("Connection setup exception. ClientSide with " + ConnectionInfo + ", " + connectionSetupExceptionStr);
}
throw new ConnectionSetupException("ClientSide. " + connectionSetupExceptionStr);
}
//Trigger the connection establish delegates once the server has replied to the connection establish
TriggerConnectionEstablishDelegates();
}
}
