public MaplePacket Read(DateTime pTransmitted, ushort pBuild, byte pLocale)
{
if (mCursor < 4)
{
return(null);
}
if (!mAES.ConfirmHeader(mBuffer, 0))
{
throw new Exception("Failed to confirm packet header");
}
ushort packetSize = mAES.GetHeaderLength(mBuffer, 0, pBuild == 255 && pLocale == 1);
if (mCursor < (packetSize + 4))
{
return(null);
}
byte[] packetBuffer = new byte[packetSize];
Buffer.BlockCopy(mBuffer, 4, packetBuffer, 0, packetSize);
bool byteheader = false;
if (pBuild == 40 && pLocale == 5)
{
// WvsBeta
Decrypt(packetBuffer, pBuild, pLocale, TransformLocale.MCRYPTO);
byteheader = true;
}
else if (pLocale == 1 && pBuild == 255)
{
// KMSB lol
Decrypt(packetBuffer, pBuild, pLocale, TransformLocale.OLDEST_MCRYPTO);
byteheader = true;
// Still reset header.
mAES.ShiftIVOld();
}
else if (pLocale == 1 || pLocale == 2)
{
// KMS / KMST
Decrypt(packetBuffer, pBuild, pLocale, TransformLocale.SPECIAL);
}
else
{
// All others lol
Decrypt(packetBuffer, pBuild, pLocale, TransformLocale.AES_MCRYPTO);
}
mCursor -= (packetSize + 4);
if (mCursor > 0)
{
Buffer.BlockCopy(mBuffer, packetSize + 4, mBuffer, 0, mCursor);
}
ushort opcode;
if (byteheader)
{
opcode = (ushort)(packetBuffer[0]);
Buffer.BlockCopy(packetBuffer, 1, packetBuffer, 0, packetSize - 1);
Array.Resize(ref packetBuffer, packetSize - 1);
}
else
{
opcode = (ushort)(packetBuffer[0] | (packetBuffer[1] << 8));
Buffer.BlockCopy(packetBuffer, 2, packetBuffer, 0, packetSize - 2);
Array.Resize(ref packetBuffer, packetSize - 2);
}
Definition definition = Config.Instance.GetDefinition(pBuild, pLocale, mOutbound, opcode);
return(new MaplePacket(pTransmitted, mOutbound, pBuild, pLocale, opcode, definition == null ? "" : definition.Name, packetBuffer));
}
private void Decrypt(byte[] pBuffer, TransformMethod pTransformLocale)
{
if ((pTransformLocale & TransformMethod.AES) != 0)
{
mAES.TransformAES(pBuffer);
}
if ((pTransformLocale & TransformMethod.MAPLE_CRYPTO) != 0)
{
for (int index1 = 1; index1 <= 6; ++index1)
{
byte firstFeedback = 0;
byte secondFeedback = 0;
byte length = (byte)(pBuffer.Length & 0xFF);
if ((index1 % 2) == 0)
{
for (int index2 = 0; index2 < pBuffer.Length; ++index2)
{
byte temp = pBuffer[index2];
temp -= 0x48;
temp = (byte)(~temp);
temp = RollLeft(temp, length & 0xFF);
secondFeedback = temp;
temp ^= firstFeedback;
firstFeedback = secondFeedback;
temp -= length;
temp = RollRight(temp, 3);
pBuffer[index2] = temp;
--length;
}
}
else
{
for (int index2 = pBuffer.Length - 1; index2 >= 0; --index2)
{
byte temp = pBuffer[index2];
temp = RollLeft(temp, 3);
temp ^= 0x13;
secondFeedback = temp;
temp ^= firstFeedback;
firstFeedback = secondFeedback;
temp -= length;
temp = RollRight(temp, 4);
pBuffer[index2] = temp;
--length;
}
}
}
}
if ((pTransformLocale & TransformMethod.KMS_CRYPTO) != 0)
{
mAES.TransformKMS(pBuffer);
}
if ((pTransformLocale & TransformMethod.OLD_KMS_CRYPTO) != 0)
{
mAES.TransformOldKMS(pBuffer);
}
if ((pTransformLocale & TransformMethod.SHIFT_IV) != 0)
{
mAES.ShiftIV();
}
if ((pTransformLocale & TransformMethod.SHIFT_IV_OLD) != 0)
{
mAES.ShiftIVOld();
}
}
