public void Test_Decrypt_VerifyEndOfMessage_FalseWhenPartiallyDecrypted()
{
using (var ciphertextStream = new MemoryStream())
using (var key = XChaChaKey.Generate())
{
var plaintext1 = RandomBytesGenerator.NextBytes(1024);
var plaintext2 = RandomBytesGenerator.NextBytes(1024);
using (var encryptionStream = new XChaChaStream(ciphertextStream, key, EncryptionMode.Encrypt, leaveOpen: true))
{
encryptionStream.Write(plaintext1);
encryptionStream.WriteFinal(plaintext2);
}
ciphertextStream.Position = 0;
using (var decryptionStream = new XChaChaStream(ciphertextStream, key, EncryptionMode.Decrypt))
{
var decryptedPlainText = new byte[plaintext1.Length];
decryptionStream.Read(decryptedPlainText);
Assert.False(decryptionStream.VerifyEndOfMessage());
}
}
}
public void Test_Encrypt_WriteDifferentAmountsToStream()
{
var plaintext1 = RandomBytesGenerator.NextBytes(157 * 1024);
var plaintext2 = RandomBytesGenerator.NextBytes(314 * 1024);
var plaintext3 = RandomBytesGenerator.NextBytes(273 * 1024);
var totalPlainTextLength = plaintext1.Length + plaintext2.Length + plaintext3.Length;
const int numberOfWrites = 3;
var expectedOutputLength = StreamHeaderLength + totalPlainTextLength + (numberOfWrites * StreamABytes);
using (var outputStream = new MemoryStream())
{
using (var key = XChaChaKey.Generate())
using (var encryptionStream = new XChaChaStream(outputStream, key, EncryptionMode.Encrypt))
{
encryptionStream.Write(plaintext1);
encryptionStream.Write(plaintext2);
encryptionStream.WriteFinal(plaintext3);
}
var ciphertext = outputStream.ToArray();
Assert.Equal(expectedOutputLength, ciphertext.Length);
}
}
public void Test_InitializeNonce_ExistingNonce_InitializesSuccessfully()
{
var nonceBytes = RandomBytesGenerator.NextBytes(NonceLength);
var nonce = new XChaChaNonce(nonceBytes);
Assert.Equal(nonce.ToArray(), nonceBytes);
}
public void Test_Decrypt_DecryptsTwoBlocks()
{
using (var ciphertextStream = new MemoryStream())
using (var key = XChaChaKey.Generate())
{
const int blockLength = 128 * 1024;
var block1 = RandomBytesGenerator.NextBytes(blockLength);
var block2 = RandomBytesGenerator.NextBytes(blockLength);
using (var encryptionStream = new XChaChaStream(ciphertextStream, key, EncryptionMode.Encrypt, leaveOpen: true))
{
encryptionStream.Write(block1);
encryptionStream.WriteFinal(block2);
}
ciphertextStream.Position = 0;
using (var decryptionStream = new XChaChaStream(ciphertextStream, key, EncryptionMode.Decrypt))
{
var decryptedBlock1 = new byte[blockLength];
var decryptedBlock2 = new byte[blockLength];
var numberOfBytesOutput1 = decryptionStream.Read(decryptedBlock1);
var numberOfBytesOutput2 = decryptionStream.Read(decryptedBlock2);
Assert.Equal(blockLength, numberOfBytesOutput1);
Assert.Equal(block1, decryptedBlock1);
Assert.Equal(blockLength, numberOfBytesOutput2);
Assert.Equal(block2, decryptedBlock2);
}
}
}
public void Test_Decrypt_DecryptsLargeBlock(int bufferLength)
{
using (var ciphertextStream = new MemoryStream())
using (var key = XChaChaKey.Generate())
{
var plaintext = RandomBytesGenerator.NextBytes(1024 * 1024);
using (var encryptionStream =
new XChaChaBufferedStream(ciphertextStream, key, EncryptionMode.Encrypt, bufferLength, leaveOpen: true))
{
encryptionStream.Write(plaintext);
}
ciphertextStream.Position = 0;
using (var decryptionStream =
new XChaChaBufferedStream(ciphertextStream, key, EncryptionMode.Decrypt, bufferLength))
{
var decryptedPlainText = new byte[plaintext.Length];
var numberOfBytesOutput = decryptionStream.Read(decryptedPlainText);
Assert.Equal(plaintext.Length, numberOfBytesOutput);
Assert.Equal(plaintext.ToArray(), decryptedPlainText);
}
}
}
public void Test_Decrypt_MultipleSmallBlocks()
{
using (var ciphertextStream = new MemoryStream())
using (var key = XChaChaKey.Generate())
{
var plaintext1 = RandomBytesGenerator.NextBytes(17);
var plaintext2 = RandomBytesGenerator.NextBytes(23);
using (var encryptionStream =
new XChaChaBufferedStream(ciphertextStream, key, EncryptionMode.Encrypt, leaveOpen: true))
{
encryptionStream.Write(plaintext1);
encryptionStream.Write(plaintext2);
}
ciphertextStream.Position = 0;
using (var decryptionStream = new XChaChaBufferedStream(ciphertextStream, key, EncryptionMode.Decrypt))
{
var plaintextLength = plaintext1.Length + plaintext2.Length;
var decryptedPlainText = new byte[plaintextLength];
var numberOfBytesOutput = decryptionStream.Read(decryptedPlainText);
Assert.Equal(plaintextLength, numberOfBytesOutput);
Assert.Equal(plaintext1.Concat(plaintext2), decryptedPlainText);
}
}
}
public void Test_InitializeNonce_LengthIncorrect_ThrowsArgumentException(int length)
{
var nonceBytes = RandomBytesGenerator.NextBytes(length);
Action action = () => new XChaChaNonce(nonceBytes);
var exception = Assert.Throws <ArgumentException>(action);
Assert.Equal("nonceBytes has incorrect length", exception.Message);
}
public void Test_Encrypt_WithLargeData_ProducesCorrectOutputLength(int bufferLength)
{
var plaintext = RandomBytesGenerator.NextBytes(1024 * 1024);
using (var outputStream = new MemoryStream())
{
using (var key = XChaChaKey.Generate())
using (var encryptionStream = new XChaChaBufferedStream(outputStream, key, EncryptionMode.Encrypt, bufferLength))
{
encryptionStream.Write(plaintext);
}
var ciphertext = outputStream.ToArray();
var numberOfBlocks = Math.Ceiling((decimal)plaintext.Length / bufferLength);
var expectedCipherTextLength = plaintext.Length + StreamHeaderLength + (StreamABytes * numberOfBlocks);
Assert.Equal(expectedCipherTextLength, ciphertext.Length);
}
}
public void Test_Encrypt_EncryptsTwoBlocks()
{
using (var ciphertextStream = new MemoryStream())
using (var key = XChaChaKey.Generate())
{
const int blockLength = 128 * 1024;
var block1 = RandomBytesGenerator.NextBytes(blockLength);
var block2 = RandomBytesGenerator.NextBytes(blockLength);
using (var encryptionStream = new XChaChaStream(ciphertextStream, key, EncryptionMode.Encrypt))
{
encryptionStream.Write(block1);
encryptionStream.WriteFinal(block2);
}
var ciphertext = ciphertextStream.ToArray();
const int numberOfWrites = 2;
const int expectedCiphertextLength = StreamHeaderLength + 2 * blockLength + (numberOfWrites * StreamABytes);
Assert.Equal(expectedCiphertextLength, ciphertext.Length);
}
}
public void Test_Decrypt_VerifyEndOfMessage_TrueWhenFullyDecrypted()
{
using (var ciphertextStream = new MemoryStream())
using (var key = XChaChaKey.Generate())
{
var plaintext = RandomBytesGenerator.NextBytes(1024 * 1024);
using (var encryptionStream =
new XChaChaBufferedStream(ciphertextStream, key, EncryptionMode.Encrypt, leaveOpen: true))
{
encryptionStream.Write(plaintext);
}
ciphertextStream.Position = 0;
using (var decryptionStream = new XChaChaBufferedStream(ciphertextStream, key, EncryptionMode.Decrypt))
{
var decryptedPlainText = new byte[plaintext.Length];
decryptionStream.Read(decryptedPlainText);
Assert.True(decryptionStream.VerifyEndOfMessage());
}
}
}
