private void EncryptStream(AesManaged EncEngine, TEncryptionKey DataKey, byte[] WorkLen)
{
WorkingStream.Position = 0;
WorkingStream.Write(WorkLen, 0, WorkLen.Length);
int read;
byte[] CurrentSegment = new byte[TEncryptionUtils.AgileSegmentSize];
int SegmentNumber = 0;
while ((read = WorkingStream.Read(CurrentSegment, 0, CurrentSegment.Length)) > 0)
{
DataKey.CalcDataIV(SegmentNumber);
SegmentNumber++;
using (ICryptoTransform Encryptor = EncEngine.CreateEncryptor(DataKey.Key, DataKey.IV))
{
using (MemoryStream outms = new MemoryStream()) //will be closed by Cryptostream
{
using (CryptoStream cs = new CryptoStream(outms, Encryptor, CryptoStreamMode.Write))
{
cs.Write(CurrentSegment, 0, read);
}
WorkingStream.Position -= read;
byte[] outArr = outms.ToArray(); //ToArray works with stream closed, and cs will close the stream.
WorkingStream.Write(outArr, 0, outArr.Length);
}
}
}
}
private void ReadSegment(long SegmentNumber)
{
if (SegmentNumber == CurrentSegmentNo)
{
return;
}
DataStream.Position = DataStreamStart + SegmentNumber * SegmentSize;
byte[] CurrentSegmentEnc = new byte[Math.Min(SegmentSize, DataStream.Length - DataStream.Position)];
DataStream.Read(CurrentSegmentEnc, CurrentSegmentEnc.Length);
using (MemoryStream msDecrypt = new MemoryStream(CurrentSegmentEnc))
{
ICryptoTransform RealDecryptor = Decryptor;
try
{
if (RealDecryptor == null)
{
Key.CalcDataIV(SegmentNumber);
RealDecryptor = EncEngine.CreateDecryptor(Key.Key, Key.IV);
}
using (CryptoStream cs = new CryptoStream(msDecrypt, RealDecryptor, CryptoStreamMode.Read))
{
cs.Read(CurrentSegment, 0, CurrentSegmentEnc.Length);
}
}
finally
{
if (RealDecryptor != Decryptor)
{
RealDecryptor.Dispose();
}
}
}
CurrentSegmentNo = SegmentNumber;
}