public PeerInfo(IPEndPoint peerEP, BinaryID networkID)
{
_peerEP = peerEP;
_networkID = networkID;
_dateCreated = DateTime.UtcNow;
}
private TcpRelayService(BinaryID networkID, int servicePort, DhtClient dhtClient)
{
_trackerManager = new TrackerManager(networkID, servicePort, dhtClient, BIT_CHAT_TRACKER_UPDATE_INTERVAL);
//start keep alive timer
_tcpRelayConnectionKeepAliveTimer = new Timer(RelayConnectionKeepAliveTimerCallback, null, TCP_RELAY_KEEP_ALIVE_INTERVAL, Timeout.Infinite);
}
public static TcpRelayService StartTcpRelay(BinaryID networkID, Connection connection, int servicePort, DhtClient dhtClient, Uri[] tracketURIs)
{
TcpRelayService relay;
lock (_relays)
{
if (_relays.ContainsKey(networkID))
{
relay = _relays[networkID];
}
else
{
relay = new TcpRelayService(networkID, servicePort, dhtClient);
_relays.Add(networkID, relay);
}
lock (relay._relayConnections)
{
relay._relayConnections.Add(connection.RemotePeerID, connection);
}
}
relay._trackerManager.AddTracker(tracketURIs);
relay._trackerManager.StartTracking();
return(relay);
}
public void StopAnnouncement(BinaryID networkID)
{
lock (_announceNetworkIDs)
{
_announceNetworkIDs.Remove(networkID);
}
}
public void StopTracking(BinaryID networkID)
{
lock (_trackedNetworkIDs)
{
_trackedNetworkIDs.Remove(networkID);
}
}
public static List <IPEndPoint> GetPeerEPs(BinaryID channelName, Connection requestingConnection)
{
BinaryID localPeerID = requestingConnection.LocalPeerID;
BinaryID remotePeerID = requestingConnection.RemotePeerID;
lock (_relays)
{
foreach (KeyValuePair <BinaryID, TcpRelayService> itemRelay in _relays)
{
BinaryID computedChannelName = Connection.GetChannelName(localPeerID, remotePeerID, itemRelay.Key);
if (computedChannelName.Equals(channelName))
{
Dictionary <BinaryID, Connection> relayConnections = itemRelay.Value._relayConnections;
List <IPEndPoint> peerEPs = new List <IPEndPoint>(relayConnections.Count);
lock (relayConnections)
{
foreach (KeyValuePair <BinaryID, Connection> itemProxyConnection in relayConnections)
{
peerEPs.Add(itemProxyConnection.Value.RemotePeerEP);
}
}
return(peerEPs);
}
}
}
return(null);
}
private void Dispose(bool disposing)
{
if (!_disposed)
{
if (_tcpRelayConnectionKeepAliveTimer != null)
{
_tcpRelayConnectionKeepAliveTimer.Dispose();
_tcpRelayConnectionKeepAliveTimer = null;
//remove all networks from all tcp relay connections
BinaryID[] networkIDs;
lock (_networks)
{
networkIDs = new BinaryID[_networks.Keys.Count];
_networks.Keys.CopyTo(networkIDs, 0);
}
lock (_tcpRelayConnections)
{
foreach (Connection relayConnection in _tcpRelayConnections.Values)
{
ThreadPool.QueueUserWorkItem(RemoveTcpRelayFromConnectionAsync, new object[] { relayConnection, networkIDs });
}
_tcpRelayConnections.Clear();
}
}
_disposed = true;
}
}
public bool IsResponseValid(BinaryID networkID, IPAddress remotePeerIP)
{
if (!_isResponse)
{
throw new Exception("Packet is not a response.");
}
byte[] servicePort = BitConverter.GetBytes(_servicePort);
BinaryID computedHmac;
using (HMACSHA256 hmacSHA256 = new HMACSHA256(networkID.ID))
{
using (MemoryStream mS2 = new MemoryStream(50))
{
mS2.Write(_challenge.ID, 0, 32); //query_challenge
byte[] ipAddr = remotePeerIP.GetAddressBytes();
mS2.Write(ipAddr, 0, ipAddr.Length); //peer_ip_address
mS2.Write(servicePort, 0, 2); //service_port
mS2.Position = 0;
computedHmac = new BinaryID(hmacSHA256.ComputeHash(mS2)); //computed hmac
}
}
return(_hmac.Equals(computedHmac));
}
private DiscoveryPacket(bool isResponse, ushort servicePort, BinaryID challenge)
{
_isResponse = isResponse;
_servicePort = servicePort;
_challenge = challenge;
_dateCreated = DateTime.UtcNow;
}
public TrackerManager(BinaryID networkID, int servicePort, DhtClient dhtClient, int customUpdateInterval, bool lookupOnly = false)
{
_networkID = networkID;
_servicePort = servicePort;
_dhtClient = dhtClient;
_customUpdateInterval = customUpdateInterval;
_lookupOnly = lookupOnly;
}
private void SendResponse(DiscoveryPacket receivedQueryPacket, BinaryID networkID, IPAddress remotePeerIP)
{
NetworkInfo network = NetUtilities.GetNetworkInfo(remotePeerIP);
DiscoveryPacket responsePacket = DiscoveryPacket.CreateResponsePacket(_announcePort, receivedQueryPacket.Challenge);
byte[] packet = responsePacket.ToArray(networkID, network.LocalIP);
_listener.SendTo(packet, 0, packet.Length, remotePeerIP);
}
public void StartTracking(BinaryID networkID)
{
lock (_trackedNetworkIDs)
{
if (!_trackedNetworkIDs.Contains(networkID))
{
_trackedNetworkIDs.Add(networkID);
}
}
}
public void StartAnnouncement(BinaryID networkID)
{
lock (_announceNetworkIDs)
{
if (!_announceNetworkIDs.Contains(networkID))
{
_announceNetworkIDs.Add(networkID);
AnnounceAsync(new BinaryID[] { networkID }, null, ANNOUNCEMENT_RETRY_COUNT);
}
}
}
public bool IsThisNetwork(BinaryID networkID)
{
if (_isResponse)
{
throw new Exception("Packet is not a query.");
}
BinaryID computedHmac;
using (HMACSHA256 hmacSHA256 = new HMACSHA256(networkID.ID))
{
computedHmac = new BinaryID(hmacSHA256.ComputeHash(_challenge.ID)); //computed hmac
}
return(_hmac.Equals(computedHmac));
}
public void RemoveNetwork(BinaryID networkID)
{
lock (_networks)
{
bool removed = _networks.Remove(networkID);
if (!removed)
{
return;
}
}
lock (_tcpRelayConnections)
{
foreach (Connection relayConnection in _tcpRelayConnections.Values)
{
ThreadPool.QueueUserWorkItem(RemoveTcpRelayFromConnectionAsync, new object[] { relayConnection, new BinaryID[] { networkID } });
}
}
}
public byte[] ToArray(BinaryID networkID, IPAddress senderPeerIP = null)
{
using (MemoryStream mS = new MemoryStream(BUFFER_MAX_SIZE))
{
if (_isResponse)
{
byte[] servicePort = BitConverter.GetBytes(_servicePort);
mS.WriteByte(6); //version
mS.Write(servicePort, 0, 2); //service_port
mS.Write(_challenge.ID, 0, 32); //query_challenge
using (HMACSHA256 hmacSHA256 = new HMACSHA256(networkID.ID))
{
using (MemoryStream mS2 = new MemoryStream(50))
{
mS2.Write(_challenge.ID, 0, 32); //query_challenge
byte[] ipAddr = senderPeerIP.GetAddressBytes();
mS2.Write(ipAddr, 0, ipAddr.Length); //peer_ip_address
mS2.Write(servicePort, 0, 2); //service_port
mS2.Position = 0;
mS.Write(hmacSHA256.ComputeHash(mS2), 0, 32); //hmac
}
}
}
else
{
mS.WriteByte(5); //version
mS.Write(_challenge.ID, 0, 32); //challenge
using (HMACSHA256 hmacSHA256 = new HMACSHA256(networkID.ID))
{
mS.Write(hmacSHA256.ComputeHash(_challenge.ID), 0, 32); //hmac
}
}
return(mS.ToArray());
}
}
public void AddNetwork(BinaryID networkID, Uri[] trackerURIs)
{
lock (_networks)
{
if (_networks.ContainsKey(networkID))
{
return;
}
_networks.Add(networkID, trackerURIs);
}
lock (_tcpRelayConnections)
{
foreach (Connection relayConnection in _tcpRelayConnections.Values)
{
ThreadPool.QueueUserWorkItem(SetupTcpRelayOnConnectionAsync, new object[] { relayConnection, networkID, trackerURIs });
}
}
}
public DiscoveryPacket(Stream s)
{
switch (s.ReadByte())
{
case 5: //query
{
byte[] bufferChallenge = new byte[32];
byte[] bufferHmac = new byte[32];
s.Read(bufferChallenge, 0, 32);
s.Read(bufferHmac, 0, 32);
_isResponse = false;
_challenge = new BinaryID(bufferChallenge);
_hmac = new BinaryID(bufferHmac);
}
break;
case 6: //response
{
byte[] bufferServicePort = new byte[2];
byte[] bufferChallenge = new byte[32];
byte[] bufferHmac = new byte[32];
s.Read(bufferServicePort, 0, 2);
s.Read(bufferChallenge, 0, 32);
s.Read(bufferHmac, 0, 32);
_isResponse = true;
_servicePort = BitConverter.ToUInt16(bufferServicePort, 0);
_challenge = new BinaryID(bufferChallenge);
_hmac = new BinaryID(bufferHmac);
}
break;
default:
throw new IOException("Invalid local discovery packet.");
}
}
private void SetupTcpRelayOnConnectionAsync(object state)
{
try
{
object[] parameters = state as object[];
Connection relayConnection = parameters[0] as Connection;
BinaryID networkID = parameters[1] as BinaryID;
Uri[] trackerURIs = parameters[2] as Uri[];
bool success = relayConnection.RequestStartTcpRelay(new BinaryID[] { networkID }, trackerURIs, TCP_RELAY_REQUEST_TIMEOUT);
if (!success)
{
//remove failed relay
lock (_tcpRelayConnections)
{
_tcpRelayConnections.Remove(relayConnection.RemotePeerEP);
}
}
}
catch
{ }
}
public static DiscoveryPacket CreateResponsePacket(ushort servicePort, BinaryID challenge)
{
return(new DiscoveryPacket(true, servicePort, challenge));
}
public static DiscoveryPacket CreateQueryPacket()
{
return(new DiscoveryPacket(false, 0, BinaryID.GenerateRandomID256()));
}
private void listener_ReceivedPacket(DiscoveryPacket packet, IPAddress remotePeerIP)
{
if (packet.IsResponse)
{
#region response process
lock (_queryPacketCache)
{
int i = _queryPacketCache.IndexOf(packet);
if (i < 0)
{
return;
}
DiscoveryPacket queryPacket = _queryPacketCache[i];
if (queryPacket.IsExpired())
{
return;
}
}
BinaryID foundNetworkID = null;
lock (_announceNetworkIDs)
{
foreach (BinaryID networkID in _announceNetworkIDs)
{
if (packet.IsResponseValid(networkID, remotePeerIP))
{
foundNetworkID = networkID;
break;
}
}
}
if (foundNetworkID != null)
{
IPEndPoint peerEP = new IPEndPoint(remotePeerIP, packet.ServicePort);
PeerInfo peerInfo = new PeerInfo(peerEP, foundNetworkID);
bool peerInCache;
lock (_peerInfoCache)
{
if (_peerInfoCache.Contains(peerInfo))
{
PeerInfo existingPeerInfo = _peerInfoCache[_peerInfoCache.IndexOf(peerInfo)];
if (existingPeerInfo.IsExpired())
{
peerInCache = false;
_peerInfoCache.Remove(existingPeerInfo);
}
else
{
peerInCache = true;
}
}
else
{
peerInCache = false;
}
}
if (!peerInCache)
{
lock (_peerInfoCache)
{
_peerInfoCache.Add(peerInfo);
}
PeerDiscovered(this, peerEP, foundNetworkID);
}
}
#endregion
}
else
{
#region query process
BinaryID foundNetworkID = null;
lock (_trackedNetworkIDs)
{
foreach (BinaryID networkID in _trackedNetworkIDs)
{
if (packet.IsThisNetwork(networkID))
{
foundNetworkID = networkID;
break;
}
}
}
if (foundNetworkID != null)
{
SendResponse(packet, foundNetworkID, remotePeerIP);
}
#endregion
}
}
