public override bool onHandshake()
{
DiffieHellman diffieHellman = new DiffieHellman(256);
//send RSA public key
RSAEncryption RSA = KeyHandler.GetPrivateKey();
base.SendMessage(new MsgRsaPublicKey(RSA.Parameters));
//Calculate and apply the public key as key
//If the key is spoofed the next packet that's being send could fail if public key is generated wrong :)
byte[] SecretHash = SHS_KeyExchange.CalculateSecretHash(RSA.Parameters.Modulus, RSA.Parameters.Exponent);
Client.Connection.protection.ApplyPrivateKey(SecretHash);//apply our secret hash based on the public key
//generate a big random key
byte[] encryptionKey = new byte[65535];
new Random(DateTime.Now.Millisecond).NextBytes(encryptionKey);
//encrypt the key with RSA
byte[] cryptedKey = RSA.Encrypt(encryptionKey, 0, encryptionKey.Length);
diffieHellman = KeyHandler.GetDiffieHellman();
byte[] diffieStr = diffieHellman.GetDiffie();
long index = Client.PrivateKeyOffset % 65535;
if (index <= 4)
{
index = 10;
}
byte[] diffieLen = BitConverter.GetBytes(diffieStr.Length);
//create a backup of encrypted RSA data
//byte[] RsaBackup = new byte[diffieLen.Length + diffieStr.Length];
//Array.Copy(cryptedKey, index - 4, RsaBackup, 0, RsaBackup.Length); //Rsa Backup Data
Array.Copy(diffieLen, 0, cryptedKey, index - 4, diffieLen.Length); //write Diffie-Hellman key length
Array.Copy(diffieStr, 0, cryptedKey, index, diffieStr.Length); //copy the diffie-hellman key in between random data
//maybe not secure adding this at the end of the encrypted data but whatever for now
//Array.Resize(ref cryptedKey, cryptedKey.Length + RsaBackup.Length);
//Array.Copy(RsaBackup, 0, cryptedKey, cryptedKey.Length - RsaBackup.Length, RsaBackup.Length);
uint KeyHash = BitConverter.ToUInt32(new CRC32().ComputeHash(cryptedKey), 0);
CertInfo certificate = new CertInfo(serverProperties.ServerCertificate);
certificate.FingerPrintMd5 = BitConverter.ToString(MD5.Create().ComputeHash(serverProperties.ServerCertificate.PrivateKey)).Replace("-", "");
certificate.FingerPrintSha1 = BitConverter.ToString(SHA1.Create().ComputeHash(serverProperties.ServerCertificate.PrivateKey)).Replace("-", "");
certificate.KeyAlgorithm = "RSA with " + Connection.RSA_KEY_SIZE + "bit";
certificate.Compression = ""; //serverProperties.Compression.ToString();
certificate.Cipher = ""; // serverProperties.Encryption.ToString();
certificate.HandshakeMethod = "RSA" + Connection.RSA_KEY_SIZE + "-DiffieHellman-AES256";
if (!serverProperties.ServerCertificate.ShowProtectionMethods)
{
certificate.Cipher = "";
certificate.Compression = "";
certificate.HandshakeMethod = "";
certificate.KeyAlgorithm = "";
}
Client.Certificate = certificate;
//Convert bytes to UINT
uint[] TempKey = new uint[SecretHash.Length];
for (int i = 0; i < TempKey.Length; i++)
{
TempKey[i] = SecretHash[i];
}
//Encrypt the diffie-hellman key with our SecretHash which is generated by our Public RSA
UnsafeXor XorEncryption = new UnsafeXor(TempKey, true);
XorEncryption.Encrypt(ref cryptedKey, 0, cryptedKey.Length);
//send encryption info + diffie-hellman
base.SendMessage(new MsgServerEncryption(serverProperties.AllowUdp, certificate, cryptedKey, KeyHash));
//apply the Encrypted Key, Yes the Encrypted Key, if spoofed the key should change at the client side ;)
Client.Connection.protection.ApplyPrivateKey(cryptedKey);
if (!base.ReceiveMessage((IMessage message) =>
{
MsgDiffiehellman diffie = message as MsgDiffiehellman;
if (diffie != null)
{
try
{
diffieHellman.HandleResponse(new PayloadReader(diffie.DiffieHellman));
Client.Connection.protection.ApplyPrivateKey(diffieHellman.Key); //apply diffie-hellman key
return(true);
}
catch { return(false); }
}
return(false);
}).Wait <bool>(false, 30000))
{
Client.Disconnect(DisconnectReason.TimeOut);
Client.onException(new Exception("Handshake went wrong, SHS_KeyExchange"), ErrorType.Core);
return(false);
}
return(true);
}
public override byte[] Encode(ref byte[] data, ref uint offset, ref uint length, ref PacketHeader packetHeader)
{
return(unsafeXor.Encrypt(ref data, (int)offset, (int)length));
}