private DhtRpcPacket Query(DhtRpcPacket packet, NodeContact contact)
{
Transaction transaction = new Transaction(contact.NodeID, contact.NodeEP);
try
{
lock (_transactions)
{
_transactions.Add(packet.TransactionID, transaction);
}
lock (transaction)
{
lock (_sendBufferStream)
{
_sendBufferStream.Position = 0;
packet.WriteTo(_sendBufferStream);
if (_proxyEnabled)
{
_manager.SendDhtPacket(contact.NodeEP, _sendBufferStream.Buffer, 0, (int)_sendBufferStream.Position);
}
else
{
_udpClient.SendTo(_sendBufferStream.Buffer, 0, (int)_sendBufferStream.Position, SocketFlags.None, contact.NodeEP);
}
}
if (!Monitor.Wait(transaction, QUERY_TIMEOUT))
{
contact.IncrementRpcFailCount();
return(null);
}
//auto add contact or update last seen time
if (contact.NodeID == null)
{
contact = transaction.ResponsePacket.SourceNode;
}
KBucket closestBucket = _routingTable.FindClosestBucket(contact.NodeID);
NodeContact bucketContact = closestBucket.FindContactInCurrentBucket(contact.NodeID);
if (bucketContact == null)
{
closestBucket.AddContactInCurrentBucket(contact);
}
else
{
bucketContact.UpdateLastSeenTime();
}
return(transaction.ResponsePacket);
}
}
finally
{
lock (_transactions)
{
_transactions.Remove(packet.TransactionID);
}
}
}
private void ReadQueryPacketsAsync(object parameter)
{
Socket udpListener = parameter as Socket;
EndPoint remoteEP;
FixMemoryStream recvBufferStream = new FixMemoryStream(BUFFER_MAX_SIZE);
FixMemoryStream sendBufferStream = new FixMemoryStream(BUFFER_MAX_SIZE);
int bytesRecv;
if (udpListener.AddressFamily == AddressFamily.InterNetwork)
{
remoteEP = new IPEndPoint(IPAddress.Any, 0);
}
else
{
remoteEP = new IPEndPoint(IPAddress.IPv6Any, 0);
}
try
{
while (true)
{
bytesRecv = udpListener.ReceiveFrom(recvBufferStream.Buffer, ref remoteEP);
if (bytesRecv > 0)
{
recvBufferStream.Position = 0;
recvBufferStream.SetLength(bytesRecv);
IPEndPoint remoteNodeEP = remoteEP as IPEndPoint;
if (NetUtilities.IsIPv4MappedIPv6Address(remoteNodeEP.Address))
{
remoteNodeEP = new IPEndPoint(NetUtilities.ConvertFromIPv4MappedIPv6Address(remoteNodeEP.Address), remoteNodeEP.Port);
}
try
{
DhtRpcPacket request = new DhtRpcPacket(recvBufferStream, remoteNodeEP.Address);
DhtRpcPacket response = ProcessPacket(request);
//send response
if (response != null)
{
sendBufferStream.Position = 0;
response.WriteTo(sendBufferStream);
udpListener.SendTo(sendBufferStream.Buffer, 0, (int)sendBufferStream.Position, SocketFlags.None, remoteEP);
}
//if contact doesnt exists then add contact else update last seen time
KBucket closestBucket = _routingTable.FindClosestBucket(request.SourceNode.NodeID);
NodeContact contact = closestBucket.FindContactInCurrentBucket(request.SourceNode.NodeID);
if (contact == null)
{
//check if the closest bucket can accomodate another contact
if (!closestBucket.IsCurrentBucketFull(true))
{
ThreadPool.QueueUserWorkItem(AddContactAfterPingAsync, request.SourceNode);
}
}
else
{
contact.UpdateLastSeenTime();
}
}
catch
{ }
}
}
}
catch (Exception ex)
{
Debug.Write("DhtClient.ReadQueryPacketsAsync", ex);
}
}
