/* * Copyright (c) Contributors, http://opensimulator.org/ * See CONTRIBUTORS.TXT for a full list of copyright holders. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * Neither the name of the OpenSim Project nor the * names of its contributors may be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ using System; using System.Collections; using System.Collections.Generic; using System.Net; using System.Net.Sockets; using System.Reflection; using OpenMetaverse.Packets; using log4net; using OpenSim.Framework; using OpenSim.Framework.Communications.Cache; using OpenSim.Region.Environment.Scenes; namespace OpenSim.Region.ClientStack.LindenUDP { /// /// This class handles the initial UDP circuit setup with a client and passes on subsequent packets to the LLPacketServer /// public class LLUDPServer : ILLClientStackNetworkHandler, IClientNetworkServer { private static readonly ILog m_log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType); /// /// The client circuits established with this UDP server. If a client exists here we can also assume that /// it is populated in clientCircuits_reverse and proxyCircuits (if relevant) /// protected Dictionary clientCircuits = new Dictionary(); public Hashtable clientCircuits_reverse = Hashtable.Synchronized(new Hashtable()); protected Dictionary proxyCircuits = new Dictionary(); private Socket m_socket; protected IPEndPoint ServerIncoming; protected byte[] RecvBuffer = new byte[4096]; protected byte[] ZeroBuffer = new byte[8192]; /// /// This is an endpoint that is reused where we don't need to protect the information from potentially /// being stomped on by other threads. /// protected EndPoint reusedEpSender = new IPEndPoint(IPAddress.Any, 0); protected int proxyPortOffset; protected AsyncCallback ReceivedData; protected LLPacketServer m_packetServer; protected Location m_location; protected uint listenPort; protected bool Allow_Alternate_Port; protected IPAddress listenIP = IPAddress.Parse("0.0.0.0"); protected IScene m_localScene; protected AssetCache m_assetCache; /// /// Manages authentication for agent circuits /// protected AgentCircuitManager m_circuitManager; public LLPacketServer PacketServer { get { return m_packetServer; } set { m_packetServer = value; } } public IScene LocalScene { set { m_localScene = value; m_packetServer.LocalScene = m_localScene; m_location = new Location(m_localScene.RegionInfo.RegionHandle); } } public ulong RegionHandle { get { return m_location.RegionHandle; } } Socket IClientNetworkServer.Server { get { return m_socket; } } public bool HandlesRegion(Location x) { return x == m_location; } public void AddScene(Scene x) { LocalScene = x; } public void Start() { ServerListener(); } public void Stop() { m_socket.Close(); } public LLUDPServer() { } public LLUDPServer( IPAddress _listenIP, ref uint port, int proxyPortOffset, bool allow_alternate_port, ClientStackUserSettings userSettings, AssetCache assetCache, AgentCircuitManager authenticateClass) { Initialise(_listenIP, ref port, proxyPortOffset, allow_alternate_port, userSettings, assetCache, authenticateClass); } /// /// Initialize the server /// /// /// /// /// /// /// /// public void Initialise( IPAddress _listenIP, ref uint port, int proxyPortOffsetParm, bool allow_alternate_port, ClientStackUserSettings userSettings, AssetCache assetCache, AgentCircuitManager circuitManager) { proxyPortOffset = proxyPortOffsetParm; listenPort = (uint) (port + proxyPortOffsetParm); listenIP = _listenIP; Allow_Alternate_Port = allow_alternate_port; m_assetCache = assetCache; m_circuitManager = circuitManager; CreatePacketServer(userSettings); // Return new port // This because in Grid mode it is not really important what port the region listens to as long as it is correctly registered. // So the option allow_alternate_ports="true" was added to default.xml port = (uint)(listenPort - proxyPortOffsetParm); } protected virtual void CreatePacketServer(ClientStackUserSettings userSettings) { new LLPacketServer(this, userSettings); } /// /// This method is called every time that we receive new UDP data. /// /// protected virtual void OnReceivedData(IAsyncResult result) { Packet packet = null; int numBytes = 1; bool ok = false; EndPoint epSender = new IPEndPoint(IPAddress.Any, 0); try { numBytes = m_socket.EndReceiveFrom(result, ref epSender); ok = true; } catch (SocketException e) { // TODO : Actually only handle those states that we have control over, re-throw everything else, // TODO: implement cases as we encounter them. //m_log.Error("[[CLIENT]: ]: Connection Error! - " + e.ToString()); switch (e.SocketErrorCode) { case SocketError.AlreadyInProgress: return; case SocketError.NetworkReset: case SocketError.ConnectionReset: break; default: throw; } } catch (ObjectDisposedException e) { m_log.DebugFormat("[CLIENT]: ObjectDisposedException: Object {0} disposed.", e.ObjectName); // Uhh, what object, and why? this needs better handling. } if (ok) { // Make sure we are getting zeroes when running off the // end of grab / degrab packets from old clients // int z; for (z = numBytes ; z < RecvBuffer.Length ; z++) RecvBuffer[z] = 0; int packetEnd = numBytes - 1; try { packet = PacketPool.Instance.GetPacket(RecvBuffer, ref packetEnd, ZeroBuffer); } catch (MalformedDataException e) { m_log.DebugFormat("[CLIENT]: Dropped Malformed Packet due to MalformedDataException: {0}", e.StackTrace); } catch (IndexOutOfRangeException e) { m_log.DebugFormat("[CLIENT]: Dropped Malformed Packet due to IndexOutOfRangeException: {0}", e.StackTrace); } catch (Exception e) { m_log.Debug("[CLIENT]: " + e); } } EndPoint epProxy = null; // If we've received a use circuit packet, then we need to decode an endpoint proxy, if one exists, before // allowing the RecvBuffer to be overwritten by the next packet. if (packet != null && packet.Type == PacketType.UseCircuitCode) { epProxy = epSender; if (proxyPortOffset != 0) { epSender = ProxyCodec.DecodeProxyMessage(RecvBuffer, ref numBytes); } } BeginReceive(); if (packet != null) { if (packet.Type == PacketType.UseCircuitCode) AddNewClient((UseCircuitCodePacket)packet, epSender, epProxy); else ProcessInPacket(packet, epSender); } } /// /// Process a successfully received packet. /// /// /// protected virtual void ProcessInPacket(Packet packet, EndPoint epSender) { try { // do we already have a circuit for this endpoint uint circuit; bool ret; lock (clientCircuits) { ret = clientCircuits.TryGetValue(epSender, out circuit); } if (ret) { //if so then send packet to the packetserver //m_log.DebugFormat("[UDPSERVER]: For endpoint {0} got packet {1}", epSender, packet.Type); m_packetServer.InPacket(circuit, packet); } } catch (Exception e) { m_log.Error("[CLIENT]: Exception in processing packet - ignoring: ", e); } } private void BeginReceive() { try { m_socket.BeginReceiveFrom( RecvBuffer, 0, RecvBuffer.Length, SocketFlags.None, ref reusedEpSender, ReceivedData, null); } catch (SocketException) { // We don't need to see this error, reset connection and get next UDP packet off the buffer // If the UDP packet is part of the same stream, this will happen several hundreds of times before // the next set of UDP data is for a valid client. //m_log.ErrorFormat("[CLIENT]: BeginRecieve threw exception " + e.Message + ": " + e.StackTrace ); // ENDLESS LOOP ON PURPOSE! ResetEndPoint(); } } private void ResetEndPoint() { try { CloseEndPoint(reusedEpSender); } catch (Exception a) { m_log.Error("[UDPSERVER]: " + a); } // ENDLESS LOOP ON PURPOSE! // We need to purge the UDP stream of crap from the client that disconnected nastily or the UDP server will die // The only way to do that is to beginreceive again! BeginReceive(); try { // m_socket.BeginReceiveFrom( // RecvBuffer, 0, RecvBuffer.Length, SocketFlags.None, ref reusedEpSender, ReceivedData, null); // Ter: For some stupid reason ConnectionReset basically kills our async event structure.. // so therefore.. we've got to tell the server to BeginReceiveFrom again. // This will happen over and over until we've gone through all packets // sent to and from this particular user. // Stupid I know.. // but Flusing the buffer would be even more stupid... so, we're stuck with this ugly method. } catch (SocketException e) { m_log.DebugFormat("[UDPSERVER]: Exception {0} : {1}", e.Message, e.StackTrace ); } } private void CloseEndPoint(EndPoint sender) { uint circuit; lock (clientCircuits) { if (clientCircuits.TryGetValue(sender, out circuit)) { m_packetServer.CloseCircuit(circuit); } } } /// /// Add a new client circuit. /// /// /// /// protected virtual void AddNewClient(UseCircuitCodePacket useCircuit, EndPoint epSender, EndPoint epProxy) { //Slave regions don't accept new clients if (m_localScene.Region_Status != RegionStatus.SlaveScene) { bool foundExistingCircuit = false; lock (clientCircuits) { if (!clientCircuits.ContainsKey(epSender)) { m_log.DebugFormat( "[CLIENT]: Adding new circuit for agent {0}, circuit code {1}", useCircuit.CircuitCode.ID, useCircuit.CircuitCode.Code); clientCircuits.Add(epSender, useCircuit.CircuitCode.Code); foundExistingCircuit = true; } } if (!foundExistingCircuit) { // This doesn't need locking as it's synchronized data clientCircuits_reverse[useCircuit.CircuitCode.Code] = epSender; lock (proxyCircuits) { proxyCircuits[useCircuit.CircuitCode.Code] = epProxy; } PacketServer.AddNewClient(epSender, useCircuit, m_assetCache, m_circuitManager, epProxy); } } // Ack the UseCircuitCode packet PacketAckPacket ack_it = (PacketAckPacket)PacketPool.Instance.GetPacket(PacketType.PacketAck); // TODO: don't create new blocks if recycling an old packet ack_it.Packets = new PacketAckPacket.PacketsBlock[1]; ack_it.Packets[0] = new PacketAckPacket.PacketsBlock(); ack_it.Packets[0].ID = useCircuit.Header.Sequence; ack_it.Header.Reliable = false; SendPacketTo(ack_it.ToBytes(), ack_it.ToBytes().Length, SocketFlags.None, useCircuit.CircuitCode.Code); PacketPool.Instance.ReturnPacket(useCircuit); } public void ServerListener() { uint newPort = listenPort; m_log.Info("[UDPSERVER]: Opening UDP socket on " + listenIP + " " + newPort + "."); ServerIncoming = new IPEndPoint(listenIP, (int)newPort); m_socket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp); m_socket.Bind(ServerIncoming); // Add flags to the UDP socket to prevent "Socket forcibly closed by host" // uint IOC_IN = 0x80000000; // uint IOC_VENDOR = 0x18000000; // uint SIO_UDP_CONNRESET = IOC_IN | IOC_VENDOR | 12; // TODO: this apparently works in .NET but not in Mono, need to sort out the right flags here. // m_socket.IOControl((int)SIO_UDP_CONNRESET, new byte[] { Convert.ToByte(false) }, null); listenPort = newPort; m_log.Info("[UDPSERVER]: UDP socket bound, getting ready to listen"); ReceivedData = OnReceivedData; m_socket.BeginReceiveFrom( RecvBuffer, 0, RecvBuffer.Length, SocketFlags.None, ref reusedEpSender, ReceivedData, null); m_log.Info("[UDPSERVER]: Listening on port " + newPort); } public virtual void RegisterPacketServer(LLPacketServer server) { m_packetServer = server; } public virtual void SendPacketTo(byte[] buffer, int size, SocketFlags flags, uint circuitcode) //EndPoint packetSender) { // find the endpoint for this circuit EndPoint sendto; try { sendto = (EndPoint)clientCircuits_reverse[circuitcode]; } catch { // Exceptions here mean there is no circuit m_log.Warn("[CLIENT]: Circuit not found, not sending packet"); return; } if (sendto != null) { //we found the endpoint so send the packet to it if (proxyPortOffset != 0) { //MainLog.Instance.Verbose("UDPSERVER", "SendPacketTo proxy " + proxyCircuits[circuitcode].ToString() + ": client " + sendto.ToString()); ProxyCodec.EncodeProxyMessage(buffer, ref size, sendto); m_socket.SendTo(buffer, size, flags, proxyCircuits[circuitcode]); } else { //MainLog.Instance.Verbose("UDPSERVER", "SendPacketTo : client " + sendto.ToString()); try { m_socket.SendTo(buffer, size, flags, sendto); } catch (SocketException SockE) { m_log.ErrorFormat("[UDPSERVER]: Caught Socket Error in the send buffer!. {0}",SockE.ToString()); } } } } public virtual void RemoveClientCircuit(uint circuitcode) { EndPoint sendto; if (clientCircuits_reverse.Contains(circuitcode)) { sendto = (EndPoint)clientCircuits_reverse[circuitcode]; clientCircuits_reverse.Remove(circuitcode); lock (clientCircuits) { if (sendto != null) { clientCircuits.Remove(sendto); } else { m_log.DebugFormat( "[CLIENT]: endpoint for circuit code {0} in RemoveClientCircuit() was unexpectedly null!", circuitcode); } } lock (proxyCircuits) { proxyCircuits.Remove(circuitcode); } } } public void RestoreClient(AgentCircuitData circuit, EndPoint userEP, EndPoint proxyEP) { //MainLog.Instance.Verbose("UDPSERVER", "RestoreClient"); UseCircuitCodePacket useCircuit = new UseCircuitCodePacket(); useCircuit.CircuitCode.Code = circuit.circuitcode; useCircuit.CircuitCode.ID = circuit.AgentID; useCircuit.CircuitCode.SessionID = circuit.SessionID; lock (clientCircuits) { if (!clientCircuits.ContainsKey(userEP)) clientCircuits.Add(userEP, useCircuit.CircuitCode.Code); else m_log.Error("[CLIENT]: clientCircuits already contains entry for user " + useCircuit.CircuitCode.Code + ". NOT adding."); } // This data structure is synchronized, so we don't need the lock if (!clientCircuits_reverse.ContainsKey(useCircuit.CircuitCode.Code)) clientCircuits_reverse.Add(useCircuit.CircuitCode.Code, userEP); else m_log.Error("[CLIENT]: clientCurcuits_reverse already contains entry for user " + useCircuit.CircuitCode.Code + ". NOT adding."); lock (proxyCircuits) { if (!proxyCircuits.ContainsKey(useCircuit.CircuitCode.Code)) { proxyCircuits.Add(useCircuit.CircuitCode.Code, proxyEP); } else { // re-set proxy endpoint proxyCircuits.Remove(useCircuit.CircuitCode.Code); proxyCircuits.Add(useCircuit.CircuitCode.Code, proxyEP); } } PacketServer.AddNewClient(userEP, useCircuit, m_assetCache, m_circuitManager, proxyEP); } } }