public byte[] DecryptData(byte[] data, int length)
{
#if DEBUG
//Logger.Debug("Decrypting " + length + " bytes");
#endif
if (_pendingBytes > 0)
{
// We have stuff left in our buffer
// What is left here will start with our count
var newData = new byte[_pendingBytes + length];
Array.Copy(_overflowBuffer, newData, _pendingBytes);
Array.Copy(data, 0, newData, _pendingBytes, length);
data = newData;
length = length + _pendingBytes;
#if DEBUG
//Logger.Debug("Added " + _pendingBytes + " bytes, now Decrypting " + length + " bytes");
#endif
_pendingBytes = 0;
}
int encLength = data[0] * 16 + 32;
#if DEBUG
//Logger.Debug("Embedded packet is of length " + encLength);
#endif
int offset = 1;
int consumed = 0;
// try avoiding using memory stream
MemoryStream fullBytes = null;
byte[] packetBytes = null;
// while we can pull a full packet from the data
while (encLength <= length - offset)// && (consumed + encLength <= MaxBufferSize))
{
#if DEBUG
//Logger.Debug("Full packet is available");
#endif
// if we have been through once before, store that data in memory stream
if (packetBytes != null)
{
if (fullBytes == null)
{
fullBytes = new MemoryStream();
}
fullBytes.Write(packetBytes, 0, packetBytes.Length);
}
// Decrypt the full packet
packetBytes = Util.getSingleton().AesDecryptBytes(data, offset, encLength, _key);
consumed = offset + encLength;
// if the amount we read was less
if (encLength < length - offset)
{
offset = consumed + 1;
encLength = data[consumed] * 16 + 32;
#if DEBUG
// Logger.Debug("Embedded packet is of length " + encLength);
#endif
}
else
{
break;
}
}
if (consumed < length)
{
#if DEBUG
//Logger.Debug("Full packet is not available, need " + encLength + ", only have " + (length - offset) + " bytes, saving " + (length - consumed) + " bytes (incl length byte)");
#endif
_pendingBytes = length - consumed;
Array.Copy(data, consumed, _overflowBuffer, 0, length - consumed);
}
if (fullBytes != null)
{
fullBytes.Write(packetBytes, 0, packetBytes.Length);
packetBytes = fullBytes.ToArray();
}
#if DEBUG
/*
if (packetBytes != null)
{
Logger.Debug("Successfully decrypted " + packetBytes.Length + " bytes");
}
else
{
Logger.Debug("Didn't decrypt any packet this round, not enough data");
}
*/
#endif
return packetBytes;
}
