private void initializeOutput()
{
if (Source != null) {
Output = new EncryptionMeta();
int size = (int)Math.Sqrt(Source.Length / PIXEL_DATA_SIZE) + EXCESS_TOLERANCE;
Output.Output = new Bitmap(size, size + DATA_ROW_NUMBER);
Output.Key = GetString(key);
}
}
private void DecryptButton_Click(object sender, EventArgs e)
{
currentOperation = OPERATION_DECRYPTION;
switch (algorithmList.SelectedIndex)
{
case CAESARS_CIPHER:
{
Stream stream = openFileDialog1.OpenFile();
try
{
currentEncryption = new CaesarsCipherEncryption(stream, new Bitmap(100, 100));
((CaesarsCipherEncryption)currentEncryption).DestinationFolder = destinationFileList.Text;
EncryptionMeta output = new EncryptionMeta();
if (keyTextBox.Text.Length > 0)
{
output.Key = keyTextBox.Text;
output.Output = new Bitmap(stream);
stream.Close();
this.currentEncryption.Output = output;
EncryptAndDecryptFunction(false);
}
else
{
MessageBox.Show("Please input key.", "Error");
keyTextBox.Focus();
}
}
catch (FileNotFoundException)
{
MessageBox.Show("No file selected", "Error");
}
}
break;
case BLOWFISH:
{
Stream stream = openFileDialog1.OpenFile();
byte[] key;
if (hexStringFlag.Checked)
key = Encryption.GetBytesFromHexString(keyTextBox.Text);
else
key = Encryption.GetBytes(keyTextBox.Text);
currentEncryption = new SHA256_Blowfish(key, null);
((SHA256_Blowfish)currentEncryption).DestinationFolder = destinationFileList.Text;
EncryptionMeta output = new EncryptionMeta();
if (keyTextBox.Text.Length > 0)
{
output.Key = keyTextBox.Text;
output.Output = new Bitmap(stream);
Color color = output.Output.GetPixel(0, 0);
stream.Close();
currentEncryption.Output = output;
EncryptAndDecryptFunction(false);
}
}
break;
case OSIAS_ENCRYPTION:
{
if (keyTextBox.Text.Length > 0)
{
currentEncryption = new OSIASEncryption(null);
OSIASEncryption enc = (OSIASEncryption)currentEncryption;
enc.DataBitmap = new Bitmap(openFileDialog1.FileName);
enc.KeyBitMap = new Bitmap(openFileDialog2.FileName);
enc.Source = new FileStream(destinationFileList.Text + "\\output", FileMode.OpenOrCreate);
this.preEncryption = normalPreEncryption;
this.duringEncryption = normalDuringEncryption;
this.postEncrtypion = OsiasPostDecryption;
EncryptAndDecryptFunction(false);
}
}
break;
}
}
private void normalPostEncryption()
{
pictureBox1.Image = currentEncryption.Output.Output;
output = currentEncryption.Output;
if (currentOperation == OPERATION_ENCRYPTION)
output.Output.Save(destinationFileList.Text + "\\" + output.Key.Substring(0, (int)Math.Min(output.Key.Length,8)) + ".bmp");
keyTextBox.Text = output.Key;
progressBar1.Value = 100;
timer.Stop();
MessageBox.Show("Finished " + currentOperation + "Time:" + timeToString(timerTicks));
timerTicks = 0;
currentOperation = null;
}
public override void applyEncryption()
{
// Problem: Size is not accurate relative to the stream length causes extra data to be encoded during
// decryption and will result to the data being corrupted.
// Solution: 00010101 (Current format) change to 00 11 01 11
// 127 64, 32 16, 8 4, 2 1
// R G B R and B Contains data G does not
//
Percentage = 0;
EncryptionMeta meta = new EncryptionMeta();
if(key == null || key.Length==0)
key = generateKey();
int size = (int)Math.Sqrt(Source.Length/3)+1;
meta.Key = byteToString(key);
meta.Output = new Bitmap(size, size);
int x = 0;
int y = 0;
int[] colorsARGB = new int[4];
byte[] buffer = new byte[bufferLength];
long streamLength = Source.Length;
int recordLimit = 3;
bool stopEncryption = false;
while (y < meta.Output.Height && stopEncryption==false) {
if (Source.Position > Source.Length)
break;
while (x < meta.Output.Width && stopEncryption == false) {
colorsARGB[0]= colorsARGB[1]= colorsARGB[2]= colorsARGB[3] = 0;
Source.Read(buffer, 0, buffer.Length);
if (streamLength < buffer.Length) {
recordLimit = (int)streamLength;
stopEncryption = true;
}
else
streamLength -= buffer.Length;
for (
int i = 0, maxIndicator = 16, dataFlag = 32;
i < recordLimit;
i++, maxIndicator /= 4, dataFlag /= 4
)
{
colorsARGB[i] = ((buffer[i] + key[i]) > byte.MaxValue) ? buffer[i] + key[i] - byte.MaxValue : buffer[i] + key[i];
if (buffer[i] == byte.MaxValue)
colorsARGB[3] += maxIndicator;
colorsARGB[3] += dataFlag;
}
meta.Output.SetPixel(x, y, Color.FromArgb(colorsARGB[3], colorsARGB[0], colorsARGB[1], colorsARGB[2]));
Percentage = ((double)(meta.Output.Width*y)+x)* buffer.Length / Source.Length;
x++;
}
x = 0;
y++;
}
Output = meta;
}
