protected void HandleConnectAccept(IPEndPoint address, BitStream stream)
{
var nonce = new Nonce();
var serverNonce = new Nonce();
nonce.Read(stream);
serverNonce.Read(stream);
var decryptPos = stream.GetBytePosition();
stream.SetBytePosition(decryptPos);
var conn = FindPendingConnection(address);
if (conn == null || conn.ConnectionState != NetConnectionState.AwaitingConnectResponse)
{
return;
}
var cParams = conn.GetConnectionParameters();
if (cParams.Nonce != nonce || cParams.ServerNonce != serverNonce)
{
return;
}
if (cParams.UsingCrypto)
{
var theCipher = new SymmetricCipher(cParams.SharedSecret);
if (!stream.DecryptAndCheckHash(NetConnection.MessageSignatureBytes, decryptPos, theCipher))
{
return;
}
}
stream.Read(out uint recvSequence);
conn.SetInitialRecvSequence(recvSequence);
string errorString = null;
if (!conn.ReadConnectAccept(stream, ref errorString))
{
RemovePendingConnection(conn);
return;
}
if (cParams.UsingCrypto)
{
stream.Read(SymmetricCipher.KeySize, cParams.InitVector);
conn.SetSymmetricCipher(new SymmetricCipher(cParams.SymmetricKey, cParams.InitVector));
}
AddConnection(conn);
RemovePendingConnection(conn);
conn.ConnectionState = NetConnectionState.Connected;
conn.OnConnectionEstablished();
}
protected void HandleDisconnect(IPEndPoint client, BitStream reader)
{
var conn = FindConnection(client);
if (conn == null)
{
return;
}
var cParams = conn.GetConnectionParameters();
var nonce = new Nonce();
nonce.Read(reader);
var serverNonce = new Nonce();
serverNonce.Read(reader);
if (nonce != cParams.Nonce || serverNonce != cParams.ServerNonce)
{
return;
}
var decryptPos = reader.GetBytePosition();
reader.SetBytePosition(decryptPos);
if (cParams.UsingCrypto)
{
var theCipher = new SymmetricCipher(cParams.SharedSecret);
if (!reader.DecryptAndCheckHash(NetConnection.MessageSignatureBytes, decryptPos, theCipher))
{
return;
}
}
reader.ReadString(out string reason);
conn.ConnectionState = NetConnectionState.Disconnected;
conn.OnConnectionTerminated(TerminationReason.ReasonRemoteDisconnectPacket, reason);
RemoveConnection(conn);
}
protected void HandlePunch(IPEndPoint address, BitStream stream)
{
var firstNonce = new Nonce();
firstNonce.Read(stream);
Console.WriteLine("Received punch packet from {0} - {1}", address, Convert.ToBase64String(firstNonce.Data));
var found = false;
NetConnection conn = null;
foreach (var pair in PendingConnections)
{
conn = pair.Value;
var cParams = conn.GetConnectionParameters();
if (conn.ConnectionState != NetConnectionState.SendingPunchPackets)
{
continue;
}
if ((cParams.IsInitiator && firstNonce != cParams.ServerNonce) || (!cParams.IsInitiator && firstNonce != cParams.Nonce))
{
continue;
}
if (cParams.PossibleAddresses.Contains(address))
{
if (cParams.IsInitiator)
{
found = true;
break;
}
continue;
}
var cont = cParams.PossibleAddresses.Any(ep => ep.Address.Equals(address.Address) && ep.AddressFamily == address.AddressFamily);
if (!cont)
{
continue;
}
if (cParams.PossibleAddresses.Count < 5)
{
cParams.PossibleAddresses.Add(address);
}
if (cParams.IsInitiator)
{
found = true;
break;
}
}
if (!found)
{
return;
}
var cParam = conn.GetConnectionParameters();
var theCipher = new SymmetricCipher(cParam.ArrangedSecret);
if (stream.DecryptAndCheckHash(NetConnection.MessageSignatureBytes, stream.GetBytePosition(), theCipher))
{
return;
}
var nextNonce = new Nonce();
nextNonce.Read(stream);
if (nextNonce != cParam.Nonce)
{
return;
}
if (stream.ReadFlag())
{
if (stream.ReadFlag())
{
cParam.Certificate = new Certificate(stream);
if (!cParam.Certificate.IsValid() || !conn.ValidateCertificate(cParam.Certificate, true))
{
return;
}
cParam.PublicKey = cParam.Certificate.GetPublicKey();
}
else
{
cParam.PublicKey = new AsymmetricKey(stream);
if (!cParam.PublicKey.IsValid() || !conn.ValidatePublicKey(cParam.PublicKey, true))
{
return;
}
}
if (PrivateKey == null || PrivateKey.GetKeySize() != cParam.PublicKey.GetKeySize())
{
cParam.PrivateKey = new AsymmetricKey(cParam.PublicKey.GetKeySize());
}
else
{
cParam.PrivateKey = PrivateKey;
}
cParam.SharedSecret = cParam.PrivateKey.ComputeSharedSecretKey(cParam.PublicKey);
RandomUtil.Read(cParam.SymmetricKey, SymmetricCipher.KeySize);
cParam.UsingCrypto = true;
}
}
protected void HandleConnectRequest(IPEndPoint address, BitStream stream)
{
if (!AllowConnections)
{
return;
}
var cParams = new ConnectionParameters();
cParams.Nonce.Read(stream);
cParams.ServerNonce.Read(stream);
stream.Read(out cParams.ClientIdentity);
if (cParams.ClientIdentity != ComputeClientIdentityToken(address, cParams.Nonce))
{
return;
}
stream.Read(out cParams.PuzzleDifficulty);
stream.Read(out cParams.PuzzleSolution);
var connect = FindConnection(address);
if (connect != null)
{
var cp = connect.GetConnectionParameters();
if (cp.Nonce == cParams.Nonce && cp.ServerNonce == cParams.ServerNonce)
{
SendConnectAccept(connect);
return;
}
}
var result = PuzzleManager.CheckSolution(cParams.PuzzleSolution, cParams.Nonce, cParams.ServerNonce, cParams.PuzzleDifficulty, cParams.ClientIdentity);
if (result != ErrorCode.Success)
{
SendConnectReject(cParams, address, "Puzzle");
return;
}
if (stream.ReadFlag())
{
if (PrivateKey == null)
{
return;
}
cParams.UsingCrypto = true;
cParams.PublicKey = new AsymmetricKey(stream);
cParams.PrivateKey = PrivateKey;
var decryptPos = stream.GetBytePosition();
stream.SetBytePosition(decryptPos);
cParams.SharedSecret = cParams.PrivateKey.ComputeSharedSecretKey(cParams.PublicKey);
var theCipher = new SymmetricCipher(cParams.SharedSecret);
if (!stream.DecryptAndCheckHash(NetConnection.MessageSignatureBytes, decryptPos, theCipher))
{
return;
}
stream.Read(SymmetricCipher.KeySize, cParams.SymmetricKey);
RandomUtil.Read(cParams.InitVector, SymmetricCipher.KeySize);
}
cParams.DebugObjectSizes = stream.ReadFlag();
stream.Read(out uint connectSequence);
if (connect != null)
{
Disconnect(connect, TerminationReason.ReasonSelfDisconnect, "NewConnection");
}
stream.ReadString(out string connectionClass);
var conn = NetConnectionRep.Create(connectionClass);
if (conn == null)
{
return;
}
conn.SetConnectionParameters(cParams);
conn.SetNetAddress(address);
conn.SetInitialRecvSequence(connectSequence);
conn.SetInterface(this);
if (cParams.UsingCrypto)
{
conn.SetSymmetricCipher(new SymmetricCipher(cParams.SymmetricKey, cParams.InitVector));
}
string errorString = null;
if (!conn.ReadConnectRequest(stream, ref errorString))
{
SendConnectReject(cParams, address, errorString);
return;
}
AddConnection(conn);
conn.ConnectionState = NetConnectionState.Connected;
conn.OnConnectionEstablished();
SendConnectAccept(conn);
}
protected void HandleArrangedConnectRequest(IPEndPoint client, BitStream reader)
{
var nonce = new Nonce();
nonce.Read(reader);
var oldConnection = FindConnection(client);
if (oldConnection != null)
{
var cp = oldConnection.GetConnectionParameters();
if (cp.Nonce == nonce)
{
SendConnectAccept(oldConnection);
return;
}
}
NetConnection conn = null;
var found = false;
foreach (var pair in PendingConnections)
{
conn = pair.Value;
var cp = conn.GetConnectionParameters();
if (conn.ConnectionState != NetConnectionState.SendingPunchPackets || cp.IsInitiator)
{
continue;
}
if (nonce != cp.Nonce)
{
continue;
}
if (cp.PossibleAddresses.Any(ep => ep.Address.Equals(client.Address) && ep.AddressFamily == client.AddressFamily))
{
found = true;
break;
}
}
if (!found)
{
return;
}
var cParams = conn.GetConnectionParameters();
var theCipher = new SymmetricCipher(cParams.ArrangedSecret);
if (!reader.DecryptAndCheckHash(NetConnection.MessageSignatureBytes, reader.GetBytePosition(), theCipher))
{
return;
}
reader.SetBytePosition(reader.GetBytePosition());
var serverNonce = new Nonce();
serverNonce.Read(reader);
if (serverNonce != cParams.ServerNonce)
{
return;
}
if (reader.ReadFlag())
{
if (PrivateKey == null)
{
return;
}
cParams.UsingCrypto = true;
cParams.PublicKey = new AsymmetricKey(reader);
cParams.PrivateKey = PrivateKey;
var decryptPos = reader.GetBytePosition();
reader.SetBytePosition(decryptPos);
cParams.SharedSecret = cParams.PrivateKey.ComputeSharedSecretKey(cParams.PublicKey);
var theCipher2 = new SymmetricCipher(cParams.SharedSecret);
if (!reader.DecryptAndCheckHash(NetConnection.MessageSignatureBytes, decryptPos, theCipher2))
{
return;
}
reader.Read(NetConnection.MessageSignatureBytes, cParams.SymmetricKey);
RandomUtil.Read(cParams.InitVector, SymmetricCipher.KeySize);
}
cParams.DebugObjectSizes = reader.ReadFlag();
reader.Read(out uint connectSequence);
if (oldConnection != null)
{
Disconnect(oldConnection, TerminationReason.ReasonSelfDisconnect, "");
}
conn.SetNetAddress(client);
conn.SetInitialRecvSequence(connectSequence);
if (cParams.UsingCrypto)
{
conn.SetSymmetricCipher(new SymmetricCipher(cParams.SymmetricKey, cParams.InitVector));
}
string errorString = null;
if (!conn.ReadConnectRequest(reader, ref errorString))
{
SendConnectReject(cParams, client, errorString);
RemovePendingConnection(conn);
return;
}
AddConnection(conn);
RemovePendingConnection(conn);
conn.ConnectionState = NetConnectionState.Connected;
conn.OnConnectionEstablished();
SendConnectAccept(conn);
}
protected bool ReadPacketHeader(BitStream stream)
{
var packetType = (NetPacketType)stream.ReadInt(2);
var sequenceNumber = stream.ReadInt(5);
/*var dataPacketFlag = */ stream.ReadFlag();
sequenceNumber = sequenceNumber | (stream.ReadInt(SequenceNumberBitSize - 5) << 5);
var highestAck = stream.ReadInt(AckSequenceNumberBitSize);
var padBits = stream.ReadInt(PacketHeaderPadBits);
if (padBits != 0)
{
return(false);
}
sequenceNumber |= (uint)(LastSeqRecvd & SequenceNumberMask);
if (sequenceNumber < LastSeqRecvd)
{
sequenceNumber += SequenceNumberWindowSize;
}
if (sequenceNumber - LastSeqRecvd > (MaxPacketWindowSize - 1))
{
return(false);
}
highestAck |= (uint)(HighestAckedSeq & AckSequenceNumberMask);
if (highestAck < HighestAckedSeq)
{
highestAck += AckSequenceNumberWindowSize;
}
if (highestAck > LastSendSeq)
{
return(false);
}
if (SymmetricCipher != null)
{
SymmetricCipher.SetupCounter(sequenceNumber, highestAck, (uint)packetType, 0);
if (!stream.DecryptAndCheckHash(MessageSignatureBytes, PacketHeaderByteSize, SymmetricCipher))
{
Console.WriteLine("Packet failed crypto");
return(false);
}
}
var ackByteCount = stream.ReadRangedU32(0, MaxAckByteCount);
if (ackByteCount > MaxAckByteCount || packetType >= NetPacketType.InvalidPacketType)
{
return(false);
}
var ackMask = new uint[MaxAckMaskSize];
var ackWordCount = (ackByteCount + 3) >> 2;
for (var i = 0U; i < ackWordCount; ++i)
{
ackMask[i] = stream.ReadInt((byte)(i == ackWordCount - 1 ? (ackByteCount - (i * 4)) * 8 : 32));
}
var sendDelay = (stream.ReadInt(8) << 3) + 4;
var ackMaskShift = sequenceNumber - LastSeqRecvd;
while (ackMaskShift > 32)
{
for (var i = MaxAckMaskSize - 1; i > 0; --i)
{
AckMask[i] = AckMask[i - 1];
}
AckMask[0] = 0;
ackMaskShift -= 32;
}
var upShifted = packetType == NetPacketType.DataPacket ? 1U : 0U;
for (var i = 0U; i < MaxAckMaskSize; ++i)
{
var nextShift = AckMask[i] >> (int)(32 - ackMaskShift);
AckMask[i] = (AckMask[i] << (int)ackMaskShift) | upShifted;
upShifted = nextShift;
}
var notifyCount = highestAck - HighestAckedSeq;
for (var i = 0U; i < notifyCount; ++i)
{
var notifyIndex = HighestAckedSeq + i + 1;
var ackMaskBit = (highestAck - notifyIndex) & 0x1FU;
var ackMaskWord = (highestAck - notifyIndex) >> 5;
var packetTransmitSuccess = (ackMask[ackMaskWord] & (1U << (int)ackMaskBit)) != 0U;
HighestAckedSendTime = 0;
HandleNotify(notifyIndex, packetTransmitSuccess);
if (HighestAckedSendTime > 0)
{
var roundTripDelta = Interface.GetCurrentTime() - (HighestAckedSendTime + (int)sendDelay);
RoundTripTime = RoundTripTime * 0.9f + roundTripDelta * 0.1f;
if (RoundTripTime < 0.0f)
{
RoundTripTime = 0.0f;
}
}
if (packetTransmitSuccess)
{
LastRecvAckAck = LastSeqRecvdAtSend[notifyIndex & PacketWindowMask];
}
}
if (sequenceNumber - LastRecvAckAck > MaxPacketWindowSize)
{
LastRecvAckAck = sequenceNumber - MaxPacketWindowSize;
}
HighestAckedSeq = highestAck;
PingSendCount = 0;
LastPingSendTime = 0;
KeepAlive();
var prevLastSequence = LastSeqRecvd;
LastSeqRecvd = sequenceNumber;
if (packetType == NetPacketType.PingPacket || (sequenceNumber - LastRecvAckAck > (MaxPacketWindowSize >> 1)))
{
SendAckPacket();
}
return(prevLastSequence != sequenceNumber && packetType == NetPacketType.DataPacket);
}