private void HandleReleasedFragment(NetIncomingMessage im) { // // read fragmentation header and combine fragments // int group; int totalBits; int chunkByteSize; int chunkNumber; int ptr = NetFragmentationHelper.ReadHeader( im.m_data, 0, out group, out totalBits, out chunkByteSize, out chunkNumber ); NetException.Assert(im.LengthBytes > ptr); NetException.Assert(group > 0); NetException.Assert(totalBits > 0); NetException.Assert(chunkByteSize > 0); int totalBytes = NetUtility.BytesToHoldBits((int)totalBits); int totalNumChunks = totalBytes / chunkByteSize; if (totalNumChunks * chunkByteSize < totalBytes) { totalNumChunks++; } NetException.Assert(chunkNumber < totalNumChunks); if (chunkNumber >= totalNumChunks) { LogWarning("Index out of bounds for chunk " + chunkNumber + " (total chunks " + totalNumChunks + ")"); return; } Dictionary <int, ReceivedFragmentGroup> groups; if (!m_receivedFragmentGroups.TryGetValue(im.SenderConnection, out groups)) { groups = new Dictionary <int, ReceivedFragmentGroup>(); m_receivedFragmentGroups[im.SenderConnection] = groups; } ReceivedFragmentGroup info; if (!groups.TryGetValue(group, out info)) { info = new ReceivedFragmentGroup(); info.Data = new byte[totalBytes]; info.ReceivedChunks = new NetBitVector(totalNumChunks); groups[group] = info; } info.ReceivedChunks[chunkNumber] = true; info.LastReceived = (float)NetTime.Now; // copy to data int offset = (chunkNumber * chunkByteSize); Buffer.BlockCopy(im.m_data, ptr, info.Data, offset, im.LengthBytes - ptr); int cnt = info.ReceivedChunks.Count(); //LogVerbose("Found fragment #" + chunkNumber + " in group " + group + " offset " + offset + " of total bits " + totalBits + " (total chunks done " + cnt + ")"); LogVerbose("Received fragment " + chunkNumber + " of " + totalNumChunks + " (" + cnt + " chunks received)"); if (info.ReceivedChunks.Count() == totalNumChunks) { // Done! Transform this incoming message im.m_data = info.Data; im.m_bitLength = (int)totalBits; im.m_isFragment = false; LogVerbose("Fragment group #" + group + " fully received in " + totalNumChunks + " chunks (" + totalBits + " bits)"); ReleaseMessage(im); } else { // data has been copied; recycle this incoming message Recycle(im); } return; }
private void Heartbeat() { VerifyNetworkThread(); double dnow = NetTime.Now; float now = (float)dnow; double delta = dnow - m_lastHeartbeat; int maxCHBpS = 1250 - m_connections.Count; if (maxCHBpS < 250) { maxCHBpS = 250; } if (delta > (1.0 / (double)maxCHBpS)) // max connection heartbeats/second max { m_frameCounter++; m_lastHeartbeat = dnow; // do handshake heartbeats if ((m_frameCounter % 3) == 0) { foreach (var kvp in m_handshakes) { NetConnection conn = kvp.Value as NetConnection; #if DEBUG // sanity check if (kvp.Key != kvp.Key) { LogWarning("Sanity fail! Connection in handshake list under wrong key!"); } #endif conn.UnconnectedHeartbeat(now); if (conn.m_status == NetConnectionStatus.Connected || conn.m_status == NetConnectionStatus.Disconnected) { #if DEBUG // sanity check if (conn.m_status == NetConnectionStatus.Disconnected && m_handshakes.ContainsKey(conn.RemoteEndpoint)) { LogWarning("Sanity fail! Handshakes list contained disconnected connection!"); m_handshakes.Remove(conn.RemoteEndpoint); } #endif break; // collection has been modified } } } #if DEBUG SendDelayedPackets(); #endif // do connection heartbeats lock (m_connections) { foreach (NetConnection conn in m_connections) { conn.Heartbeat(now, m_frameCounter); if (conn.m_status == NetConnectionStatus.Disconnected) { // // remove connection // m_connections.Remove(conn); m_connectionLookup.Remove(conn.RemoteEndpoint); break; // can't continue iteration here } } } // send unsent unconnected messages NetTuple <IPEndPoint, NetOutgoingMessage> unsent; while (m_unsentUnconnectedMessages.TryDequeue(out unsent)) { NetOutgoingMessage om = unsent.Item2; #if DEBUG if (om.m_messageType == NetMessageType.NatPunchMessage) { LogDebug("Sending Nat Punch Message to " + unsent.Item1.ToString()); } #endif bool connReset; int len = om.Encode(m_sendBuffer, 0, 0); SendPacket(len, unsent.Item1, 1, out connReset); Interlocked.Decrement(ref om.m_recyclingCount); if (om.m_recyclingCount <= 0) { Recycle(om); } } } // // read from socket // if (m_socket == null) { return; } if (!m_socket.Poll(1000)) // wait up to 1 ms for data to arrive { return; } //if (m_socket == null || m_socket.Available < 1) // return; do { int bytesReceived = 0; try { bytesReceived = m_socket.ReceiveFrom(m_receiveBuffer, 0, m_receiveBuffer.Length, ref m_senderRemote); } catch (SocketException sx) { if (sx.SocketErrorCode == SocketError.ConnectionReset) { // connection reset by peer, aka connection forcibly closed aka "ICMP port unreachable" // we should shut down the connection; but m_senderRemote seemingly cannot be trusted, so which connection should we shut down?! // So, what to do? return; } LogWarning(sx.ToString()); return; } if (bytesReceived < NetConstants.HeaderByteSize) { return; } //LogVerbose("Received " + bytesReceived + " bytes"); IPEndPoint ipsender = (IPEndPoint)m_senderRemote; if (ipsender.Port == 1900) { // UPnP response try { string resp = System.Text.Encoding.UTF8.GetString(m_receiveBuffer, 0, bytesReceived); if (resp.Contains("upnp:rootdevice")) { resp = resp.Substring(resp.ToLower().IndexOf("location:") + 9); resp = resp.Substring(0, resp.IndexOf("\r")).Trim(); m_upnp.ExtractServiceUrl(resp); return; } } catch { } } NetConnection sender = null; m_connectionLookup.TryGetValue(ipsender, out sender); double receiveTime = NetTime.Now; // // parse packet into messages // int numMessages = 0; int ptr = 0; while ((bytesReceived - ptr) >= NetConstants.HeaderByteSize) { // decode header // 8 bits - NetMessageType // 1 bit - Fragment? // 15 bits - Sequence number // 16 bits - Payload length in bits numMessages++; NetMessageType tp = (NetMessageType)m_receiveBuffer[ptr++]; byte low = m_receiveBuffer[ptr++]; byte high = m_receiveBuffer[ptr++]; bool isFragment = ((low & 1) == 1); ushort sequenceNumber = (ushort)((low >> 1) | (((int)high) << 7)); ushort payloadBitLength = (ushort)(m_receiveBuffer[ptr++] | (m_receiveBuffer[ptr++] << 8)); int payloadByteLength = NetUtility.BytesToHoldBits(payloadBitLength); if (bytesReceived - ptr < payloadByteLength) { LogWarning("Malformed packet; stated payload length " + payloadByteLength + ", remaining bytes " + (bytesReceived - ptr)); return; } try { NetException.Assert(tp <NetMessageType.Unused1 || tp> NetMessageType.Unused29); if (tp >= NetMessageType.LibraryError) { if (sender != null) { sender.ReceivedLibraryMessage(tp, ptr, payloadByteLength); } else { ReceivedUnconnectedLibraryMessage(receiveTime, ipsender, tp, ptr, payloadByteLength); } } else { if (sender == null && !m_configuration.IsMessageTypeEnabled(NetIncomingMessageType.UnconnectedData)) { return; // dropping unconnected message since it's not enabled } NetIncomingMessage msg = CreateIncomingMessage(NetIncomingMessageType.Data, payloadByteLength); msg.m_isFragment = isFragment; msg.m_receiveTime = receiveTime; msg.m_sequenceNumber = sequenceNumber; msg.m_receivedMessageType = tp; msg.m_senderConnection = sender; msg.m_senderEndpoint = ipsender; msg.m_bitLength = payloadBitLength; Buffer.BlockCopy(m_receiveBuffer, ptr, msg.m_data, 0, payloadByteLength); if (sender != null) { if (tp == NetMessageType.Unconnected) { // We're connected; but we can still send unconnected messages to this peer msg.m_incomingMessageType = NetIncomingMessageType.UnconnectedData; ReleaseMessage(msg); } else { // connected application (non-library) message sender.ReceivedMessage(msg); } } else { // at this point we know the message type is enabled // unconnected application (non-library) message msg.m_incomingMessageType = NetIncomingMessageType.UnconnectedData; ReleaseMessage(msg); } } } catch (Exception ex) { LogError("Packet parsing error: " + ex.Message + " from " + ipsender); } ptr += payloadByteLength; } m_statistics.PacketReceived(bytesReceived, numMessages); if (sender != null) { sender.m_statistics.PacketReceived(bytesReceived, numMessages); } } while (m_socket.Available > 0); }
/// <summary> /// Reads a signed integer stored in 1 to 64 bits, written using Write(Int64, Int32) /// </summary> public Int64 ReadInt64(int numberOfBits) { NetException.Assert(((numberOfBits > 0) && (numberOfBits <= 64)), "ReadInt64(bits) can only read between 1 and 64 bits"); return((long)ReadUInt64(numberOfBits)); }
/// <summary> /// Sets all bits/booleans to zero/false /// </summary> public void Clear() { Array.Clear(m_data, 0, m_data.Length); m_numBitsSet = 0; NetException.Assert(this.IsEmpty()); }
/// <summary> /// Gets the bit/bool at the specified index /// </summary> public bool Get(int bitIndex) { NetException.Assert(bitIndex >= 0 && bitIndex < m_capacity); return((m_data[bitIndex / 32] & (1 << (bitIndex % 32))) != 0); }
// remoteWindowStart is remote expected sequence number; everything below this has arrived properly // seqNr is the actual nr received internal override void ReceiveAcknowledge(float now, int seqNr) { // late (dupe), on time or early ack? int relate = NetUtility.RelativeSequenceNumber(seqNr, m_windowStart); if (relate < 0) { //m_connection.m_peer.LogDebug("Received late/dupe ack for #" + seqNr); return; // late/duplicate ack } if (relate == 0) { //m_connection.m_peer.LogDebug("Received right-on-time ack for #" + seqNr); // ack arrived right on time NetException.Assert(seqNr == m_windowStart); m_receivedAcks[m_windowStart] = false; DestoreMessage(m_windowStart % m_windowSize); m_windowStart = (m_windowStart + 1) % NetConstants.NumSequenceNumbers; // advance window if we already have early acks while (m_receivedAcks.Get(m_windowStart)) { //m_connection.m_peer.LogDebug("Using early ack for #" + m_windowStart + "..."); m_receivedAcks[m_windowStart] = false; NetException.Assert(m_storedMessages[m_windowStart % m_windowSize].Message == null); // should already be destored m_windowStart = (m_windowStart + 1) % NetConstants.NumSequenceNumbers; //m_connection.m_peer.LogDebug("Advancing window to #" + m_windowStart); } return; } // // early ack... (if it has been sent!) // // If it has been sent either the m_windowStart message was lost // ... or the ack for that message was lost // //m_connection.m_peer.LogDebug("Received early ack for #" + seqNr); int sendRelate = NetUtility.RelativeSequenceNumber(seqNr, m_sendStart); if (sendRelate <= 0) { // yes, we've sent this message - it's an early (but valid) ack if (m_receivedAcks[seqNr]) { // we've already destored/been acked for this message } else { DestoreMessage(seqNr % m_windowSize); m_receivedAcks[seqNr] = true; } } else if (sendRelate > 0) { // uh... we haven't sent this message yet? Weird, dupe or error... return; } // Ok, lets resend all missing acks int rnr = seqNr; do { rnr--; if (rnr < 0) { rnr = NetConstants.NumSequenceNumbers - 1; } if (m_receivedAcks[rnr]) { // m_connection.m_peer.LogDebug("Not resending #" + rnr + " (since we got ack)"); } else { int slot = rnr % m_windowSize; NetException.Assert(m_storedMessages[slot].Message != null); if (m_storedMessages[slot].NumSent == 1) { // just sent once; resend immediately since we found gap in ack sequence NetOutgoingMessage rmsg = m_storedMessages[slot].Message; //m_connection.m_peer.LogVerbose("Resending #" + rnr + " (" + rmsg + ")"); if (now - m_storedMessages[slot].LastSent < (m_resendDelay * 0.35f)) { // already resent recently } else { m_storedMessages[slot].LastSent = now; m_storedMessages[slot].NumSent++; m_connection.m_statistics.MessageResent(MessageResendReason.HoleInSequence); m_connection.QueueSendMessage(rmsg, rnr); } } } } while (rnr != m_windowStart); }
private void SendCallBack(IAsyncResult res) { NetException.Assert(res.IsCompleted == true); m_socket.EndSendTo(res); }