public void AuthenticatedSymmetricAlgorithmVerifierTestNegativeStandardEncryptAuthenticatedDecryptTest()
{
byte[] plaintext = Encoding.UTF8.GetBytes("Plaintext");
byte[] ciphertext = null;
byte[] key = null;
SymmetricEncryptionState encryptionState = null;
using (SymmetricAlgorithm encryptAes = new AesCng().EnableLogging())
{
key = encryptAes.Key;
using (MemoryStream ms = new MemoryStream())
using (CryptoStream cs = new CryptoStream(ms, encryptAes.CreateEncryptor(), CryptoStreamMode.Write))
{
cs.Write(plaintext, 0, plaintext.Length);
cs.FlushFinalBlock();
ciphertext = ms.ToArray();
encryptionState = encryptAes.GetLastEncryptionState();
}
}
using (SymmetricAlgorithm decryptAes = (new AuthenticatedAesCng() as SymmetricAlgorithm).EnableDecryptionVerification(encryptionState))
{
decryptAes.Key = key;
decryptAes.IV = new byte[] { 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1 };
using (MemoryStream ms = new MemoryStream())
using (CryptoStream cs = new CryptoStream(ms, decryptAes.CreateDecryptor(), CryptoStreamMode.Write))
{
cs.Write(ciphertext, 0, ciphertext.Length);
cs.FlushFinalBlock();
}
}
Assert.Fail("Decryption should have failed.");
}