public int doFinal(
byte[] outBytes,
int outOff)
{
int blockSize = cipher.getBlockSize();
//
// pad with zeroes
//
if (this.padding == null)
{
while (bufOff < blockSize)
{
buf[bufOff] = 0;
bufOff++;
}
}
else
{
padding.addPadding(buf, bufOff);
}
cipher.processBlock(buf, 0, mac, 0);
cipher.getMacBlock(mac);
Array.Copy(mac, 0, outBytes, outOff, macSize);
reset();
return(macSize);
}
/**
* Process the last block in the buffer. If the buffer is currently
* full and padding needs to be added a call to doFinal will produce
* 2 * getBlockSize() bytes.
*
* @param out the array the block currently being held is copied into.
* @param outOff the offset at which the copying starts.
* @return the number of output bytes copied to out.
* @exception DataLengthException if there is insufficient space in out for
* the output or we are decrypting and the input is not block size aligned.
* @exception IllegalStateException if the underlying cipher is not
* initialised.
* @exception InvalidCipherTextException if padding is expected and not found.
*/
public override int doFinal(
byte[] outBytes,
int outOff)
//throws DataLengthException, IllegalStateException, InvalidCipherTextException
{
int blockSize = cipher.getBlockSize();
int resultLen = 0;
if (forEncryption)
{
if (bufOff == blockSize)
{
if ((outOff + 2 * blockSize) > outBytes.Length)
{
reset();
throw new DataLengthException("output buffer too short");
}
resultLen = cipher.processBlock(buf, 0, outBytes, outOff);
bufOff = 0;
}
padding.addPadding(buf, bufOff);
resultLen += cipher.processBlock(buf, 0, outBytes, outOff + resultLen);
reset();
}
else
{
if (bufOff == blockSize)
{
resultLen = cipher.processBlock(buf, 0, buf, 0);
bufOff = 0;
}
else
{
reset();
throw new DataLengthException("last block incomplete in decryption");
}
try
{
resultLen -= padding.padCount(buf);
Array.Copy(buf, 0, outBytes, outOff, resultLen);
}
finally
{
reset();
}
}
return(resultLen);
}