public void VerifyEncryptedSizeCalculationsModBlockSize()
{
/*
* Test with size that is (MOD BlockSize == 0)
*/
short padding;
var encryptedSize = EncryptionManager.CalculateEncryptedFileSize(1024, out padding);
// Header size is 1k bytes. Expect to see header + plaintext
Assert.AreEqual(EncryptedFileHeader.HeaderSize + 1024 + 16, encryptedSize);
Assert.AreEqual(0, padding);
}
public void VerifyEncryptedSizeCalculations1Byte()
{
/*
* Test with 1 byte input
*/
short padding;
var encryptedSize = EncryptionManager.CalculateEncryptedFileSize(1, out padding);
// Header size is 1k bytes. Expect to see header + blocksize + padding
int expectedEncryptedSize = EncryptedFileHeader.HeaderSize + 16 + padding;
Assert.AreEqual(expectedEncryptedSize, encryptedSize);
Assert.AreEqual(1, padding);
}
public void EncryptAndDecryptFileExactBlockBoundary()
{
byte[] inputBuffer = CreateInputBuffer(EncryptedFileHeader.HeaderSize);
short padding;
long expectedEncryptedSize =
EncryptionManager.CalculateEncryptedFileSize(inputBuffer.Length, out padding);
MemoryStream inputStream = null;
MemoryStream outputStream = null;
EncryptionManager encryptionManager = null;
byte[] encryptedData;
byte[] decryptedData;
try
{
inputStream = new MemoryStream(inputBuffer);
outputStream = new MemoryStream();
encryptionManager = new EncryptionManager(
ReadTestCert(),
EncryptionMode.Encrypt,
outputStream,
inputBuffer.Length);
int written = 0;
int blockSize = 2048;
byte[] buf = new byte[blockSize];
while (true)
{
int read = inputStream.Read(buf, 0, blockSize);
if (read == blockSize)
{
written += encryptionManager.TransformBlock(buf, 0, read);
}
else
{
// Read the end of the input stream
written += encryptionManager.TransformFinalBlock(buf, 0, read);
break;
}
}
encryptedData = outputStream.ToArray();
Assert.AreEqual(expectedEncryptedSize, encryptedData.Length);
Assert.AreEqual(encryptedData.Length, written);
}
finally
{
encryptionManager?.Dispose();
outputStream?.Dispose();
inputStream?.Dispose();
}
long expectedDecryptedSize =
EncryptionManager.CalculateDecryptedFileSize(expectedEncryptedSize, out padding);
Assert.AreEqual(expectedDecryptedSize, inputBuffer.Length);
try
{
inputStream = new MemoryStream(encryptedData);
outputStream = new MemoryStream();
encryptionManager = new EncryptionManager(
ReadTestCert(),
EncryptionMode.Decrypt,
outputStream,
encryptedData.Length);
int written = 0;
int blockSize = 2048;
byte[] buf = new byte[blockSize];
while (true)
{
int read = inputStream.Read(buf, 0, blockSize);
if (read == blockSize)
{
written += encryptionManager.TransformBlock(buf, 0, read);
}
else
{
// Read the end of the input stream
written += encryptionManager.TransformFinalBlock(buf, 0, read);
break;
}
}
decryptedData = outputStream.ToArray();
Assert.AreEqual(decryptedData.Length, written);
Assert.AreEqual(inputBuffer.Length, decryptedData.Length);
}
finally
{
encryptionManager?.Dispose();
outputStream?.Dispose();
inputStream?.Dispose();
}
for (int i = 0; i < decryptedData.Length; i++)
{
if (decryptedData[i] != i % 256)
{
Assert.Fail("Invalid data at byte " + i);
}
}
}