private DhtRpcPacket ProcessQuery(DhtRpcPacket query, IPAddress remoteNodeIP)
{
AddNode(new IPEndPoint(remoteNodeIP, query.SourceNodePort));
switch (query.Type)
{
case DhtRpcType.PING:
return(DhtRpcPacket.CreatePingPacket(_currentNode));
case DhtRpcType.FIND_NODE:
return(DhtRpcPacket.CreateFindNodePacketResponse(_currentNode, query.NetworkID, _routingTable.GetKClosestContacts(query.NetworkID)));
case DhtRpcType.FIND_PEERS:
PeerEndPoint[] peers = _currentNode.GetPeers(query.NetworkID);
if (peers.Length == 0)
{
return(DhtRpcPacket.CreateFindPeersPacketResponse(_currentNode, query.NetworkID, _routingTable.GetKClosestContacts(query.NetworkID), peers));
}
else
{
return(DhtRpcPacket.CreateFindPeersPacketResponse(_currentNode, query.NetworkID, new NodeContact[] { }, peers));
}
case DhtRpcType.ANNOUNCE_PEER:
_currentNode.StorePeer(query.NetworkID, new PeerEndPoint(remoteNodeIP, query.ServicePort));
return(DhtRpcPacket.CreateAnnouncePeerPacketResponse(_currentNode, query.NetworkID, _currentNode.GetPeers(query.NetworkID)));
default:
throw new Exception("Invalid DHT-RPC type.");
}
}
private DhtRpcPacket ProcessPacket(DhtRpcPacket packet)
{
switch (packet.PacketType)
{
case RpcPacketType.Query:
#region Query
DhtRpcPacket response = null;
switch (packet.QueryType)
{
case RpcQueryType.PING:
#region PING
{
response = DhtRpcPacket.CreatePingPacketResponse(packet.TransactionID, _currentNode);
}
#endregion
break;
case RpcQueryType.FIND_NODE:
#region FIND_NODE
{
NodeContact[] contacts = _routingTable.GetKClosestContacts(packet.NetworkID);
response = DhtRpcPacket.CreateFindNodePacketResponse(packet.TransactionID, _currentNode, packet.NetworkID, contacts);
}
#endregion
break;
case RpcQueryType.FIND_PEERS:
#region GET_PEERS
{
PeerEndPoint[] peers = _currentNode.GetPeers(packet.NetworkID);
NodeContact[] contacts;
if (peers.Length < 1)
{
contacts = _routingTable.GetKClosestContacts(packet.NetworkID);
}
else
{
contacts = new NodeContact[] { }
};
response = DhtRpcPacket.CreateFindPeersPacketResponse(packet.TransactionID, _currentNode, packet.NetworkID, contacts, peers, GetToken(packet.SourceNode.NodeEP.Address));
}
#endregion
break;
case RpcQueryType.ANNOUNCE_PEER:
#region ANNOUNCE_PEER
{
IPAddress remoteNodeIP = packet.SourceNode.NodeEP.Address;
if (IsTokenValid(packet.Token, remoteNodeIP))
{
_currentNode.StorePeer(packet.NetworkID, new PeerEndPoint(remoteNodeIP, packet.ServicePort));
}
response = DhtRpcPacket.CreateAnnouncePeerPacketResponse(packet.TransactionID, _currentNode, packet.NetworkID);
}
#endregion
break;
}
return(response);
#endregion
case RpcPacketType.Response:
#region Response
Transaction transaction = null;
lock (_transactions)
{
if (_transactions.ContainsKey(packet.TransactionID))
{
transaction = _transactions[packet.TransactionID];
}
}
if ((transaction != null) && ((transaction.RemoteNodeID == null) || transaction.RemoteNodeID.Equals(packet.SourceNode.NodeID)) && transaction.RemoteNodeEP.Equals(packet.SourceNode.NodeEP))
{
lock (transaction)
{
transaction.ResponsePacket = packet;
Monitor.Pulse(transaction);
}
}
return(null);
#endregion
}
return(null);
}