public byte[] processHandleAuthChallenge_Response(byte[] data, int maxBytes)
{
int blobSize = (int)data[4];
byte[] encryptedBlob = new byte[blobSize];
byte[] decryptedBlob = new byte[blobSize];
ArrayUtils.copy(data, 6, encryptedBlob, 0, blobSize);
// Reset IV to 0
tf.setIV(blankIV);
tf.decrypt(encryptedBlob, decryptedBlob);
byte[] receivedMD5 = new byte[16];
ArrayUtils.copy(decryptedBlob, 1, receivedMD5, 0, 16);
// Security says that must be the same
if (!ArrayUtils.equal(receivedMD5, md5edChallenge))
{
Output.WriteLine("The Md5 from client and Our Md5 are not same, aborting");
Output.WriteLine("Decrypted (TF) blob:" + StringUtils.bytesToString(decryptedBlob));
Output.WriteLine("Stored MD5ed Challenge:" + StringUtils.bytesToString(md5edChallenge));
throw new AuthException("Md5 challenge differs");
}
// We take the pass from the decrypted Blob and subtract 1 byte, the ending "0"
int passSize = ((int)decryptedBlob[23]) - 1;
byte[] passwordB = new byte[passSize];
ArrayUtils.copy(decryptedBlob, 25, passwordB, 0, passSize);
Output.OptWriteLine("-> Password decrypted, size:" + passSize);
// Set WorldList password
wl.setPassword(StringUtils.bytesToString_NS(md5.digest(passwordB)));
if (Store.dbManager.AuthDbHandler.fetchWordList(ref wl))
{
// Do calculations magic
byte[] hexUserID = NumericalUtils.uint32ToByteArray((UInt32)wl.getUserID(), 1);
byte[] nameH = new byte[33];
string name = wl.getUsername();
for (int i = 0; i < name.Length; i++)
{
nameH[i] = (byte)name[i];
}
byte[] padding = new byte[4]; // 4 empty byte ==> [0x00,0x00,0x00,0x00]
// +10 mins from now, so 60secs per min
byte[] expiredTime = TimeUtils.getUnixTime(60 * 10);
byte[] padding2 = new byte[32]; // 32 empty byte ==> [0x00,0x00,0x00,0x00,...]
byte[] pubModulusH = wl.getPublicModulus();
byte[] createdTime = NumericalUtils.uint32ToByteArray((UInt32)wl.getTimeCreated(), 1);
// Create signed data
DynamicArray signedData = new DynamicArray();
signedData.append(new byte[] { 0x01 });
signedData.append(hexUserID);
signedData.append(nameH);
signedData.append(new byte[] { 0x00, 0x01 });
signedData.append(padding);
signedData.append(expiredTime);
signedData.append(padding2);
signedData.append(new byte[] { 0x00, 0x11 });
signedData.append(pubModulusH);
signedData.append(createdTime);
byte[] md5FromStructure = md5.digest(signedData.getBytes());
// Do MD5 to the signed data and RSA encrypt the result
byte[] signature = rsa.signWithMD5(md5FromStructure);
Output.OptWriteLine("-> Signing with RSA");
// Do: privExp = Twofish(privExp)
byte[] privExp = wl.getPrivateExponent();
byte[] buffer = new byte[privExp.Length];
// We keep the Key from before this part
// Set the challenge we saved before as IV
tf.setIV(challenge);
tf.encrypt(privExp, buffer);
privExp = buffer;
byte [] privExpSize = NumericalUtils.uint16ToByteArray((UInt16)privExp.Length, 1);
// Calculate offsets
int offsetAuthData = 33 + wl.getCharPack().getPackLength() + wl.getWorldPack().getTotalSize();
int offsetEncryptedData = offsetAuthData + signature.Length + signedData.getSize() + 2;
int offsetCharData = 33;
int offsetServerData = 33 + wl.getCharPack().getPackLength();
int offsetUsernameLast = offsetEncryptedData + 2 + privExp.Length;
// Create the auth header
DynamicArray authHeader = new DynamicArray();
authHeader.append(new byte[] { 0x0b, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 });
authHeader.append(NumericalUtils.uint16ToByteArray((UInt16)offsetAuthData, 1));
authHeader.append(NumericalUtils.uint16ToByteArray((UInt16)offsetEncryptedData, 1));
authHeader.append(new byte[] { 0x1f, 0x00, 0x00, 0x00 });
authHeader.append(NumericalUtils.uint16ToByteArray((UInt16)offsetCharData, 1));
authHeader.append(new byte[] { 0x6E, 0xD1, 0x00, 0x00 });
authHeader.append(NumericalUtils.uint32ToByteArray((UInt32)offsetServerData, 1));
authHeader.append(NumericalUtils.uint32ToByteArray((UInt32)offsetUsernameLast, 1));
byte [] usernameSize = NumericalUtils.uint16ToByteArray((UInt16)(name.Length + 1), 1);
// Create the semiResponse (full data, except the total size)
DynamicArray semiResponse = new DynamicArray();
semiResponse.append(authHeader.getBytes());
semiResponse.append(wl.getCharPack().getByteContents());
semiResponse.append(wl.getWorldPack().getByteContents());
semiResponse.append(new byte[] { 0x36, 0x01 });
semiResponse.append(signature);
semiResponse.append(signedData.getBytes());
semiResponse.append(privExpSize);
semiResponse.append(privExp);
semiResponse.append(usernameSize);
byte [] tempName = new byte[name.Length];
for (int i = 0; i < name.Length; i++)
{
tempName[i] = (byte)name[i];
}
semiResponse.append(tempName);
semiResponse.append(new byte[] { 0x00 });
int bigSize = semiResponse.getSize();
bigSize += 0x8000; // Add TCP Len Var
byte [] finalSize = NumericalUtils.uint16ToByteArray((UInt16)bigSize, 0);
// Create the finalResponse (full data, plus total size)
DynamicArray finalResponse = new DynamicArray();
finalResponse.append(finalSize);
finalResponse.append(semiResponse.getBytes());
Output.OptWriteLine("Sending world list.");
status = -1;
return(finalResponse.getBytes());
}
byte [] worldListPacket = { 0x00, 0x00 };
status = -1; // trick
return(worldListPacket);
}