private byte[] HandleLobbyPacket(byte[] lobbyPayload)
{
if (lobbyPayload.Length <= 24)
{
return(null); // ping, not interested
}
if (lobbyPayload[12] == 0x09)
{
var key = CalculateEncryption(
lobbyPayload.Skip(52).Take(32).ToArray(),
lobbyPayload.Skip(116).Take(4).ToArray());
_decrypter = new Blowfish(key);
return(lobbyPayload); // plain text
}
if (_decrypter == null)
{
// unable to decrypt
// but since salt is hard-coded in game binary and time range is relatively small
// we can brute force the password in a few seconds if we really need its data
lobbyPayload[0x0E] = 0xDE; // DEcrypt
lobbyPayload[0x0F] = 0xFA; // FAiled
return(lobbyPayload);
}
var dat = _decrypter.DecryptECB(lobbyPayload);
Buffer.BlockCopy(lobbyPayload, 0, dat, 0, 16); // restore header
return(dat);
}
