Example #1
0
        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;
            }
        }
Example #2
0
        protected void HandleConnectChallengeResponse(IPEndPoint address, BitStream stream)
        {
            var conn = FindPendingConnection(address);

            if (conn == null || conn.ConnectionState != NetConnectionState.AwaitingChallengeResponse)
            {
                return;
            }

            var theNonce = new Nonce();

            theNonce.Read(stream);

            var cParams = conn.GetConnectionParameters();

            if (theNonce != cParams.Nonce)
            {
                return;
            }

            stream.Read(out cParams.ClientIdentity);
            cParams.ServerNonce.Read(stream);
            stream.Read(out cParams.PuzzleDifficulty);

            if (cParams.PuzzleDifficulty > ClientPuzzleManager.MaxPuzzleDifficulty)
            {
                return;
            }

            if (stream.ReadFlag())
            {
                if (stream.ReadFlag())
                {
                    cParams.Certificate = new Certificate(stream);
                    if (!cParams.Certificate.IsValid() || !conn.ValidateCertificate(cParams.Certificate, true))
                    {
                        return;
                    }

                    cParams.PublicKey = cParams.Certificate.GetPublicKey();
                }
                else
                {
                    cParams.PublicKey = new AsymmetricKey(stream);
                    if (!cParams.PublicKey.IsValid() || !conn.ValidatePublicKey(cParams.PublicKey, true))
                    {
                        return;
                    }
                }

                if (PrivateKey == null || PrivateKey.GetKeySize() != cParams.PublicKey.GetKeySize())
                {
                    cParams.PrivateKey = new AsymmetricKey(cParams.PublicKey.GetKeySize());
                }
                else
                {
                    cParams.PrivateKey = PrivateKey;
                }

                cParams.SharedSecret = cParams.PrivateKey.ComputeSharedSecretKey(cParams.PublicKey);
                RandomUtil.Read(cParams.SymmetricKey, SymmetricCipher.KeySize);

                cParams.UsingCrypto = true;
            }

            conn.ConnectionState  = NetConnectionState.ComputingPuzzleSolution;
            conn.ConnectSendCount = 0;

            cParams.PuzzleSolution = 0;

            conn.ConnectLastSendTime = CurrentTime;

            ContinuePuzzleSolution(conn);
        }