public void TestRandomBytes(Symmetric_AES.KeySize keySize, int?numBytes)
{
var key = Symmetric_AES.GenerateRandomKey(keySize);
byte[] input = null;
if (numBytes.HasValue)
{
input = GetRandomBytes(numBytes.Value, numBytes.Value);
}
byte[] encrypted, decrypted;
using (var algorithm = new Symmetric_AES_CBC())
{
encrypted = algorithm.EncryptBytes(input, key);
}
using (var algorithm = new Symmetric_AES_CBC())
{
decrypted = algorithm.DecryptBytes(encrypted, key);
}
if (input == null)
{
Assert.IsNull(encrypted, "encrypted");
Assert.IsNull(decrypted, "decrypted");
}
else
{
Assert.IsTrue(encrypted.Length >= numBytes, "encrypted.Length");
Assert.IsTrue(decrypted.SequenceEqual(input), "Decrypted does not match original.");
}
}
public void TestIncorrectKeyFails(Symmetric_AES.KeySize keySize)
{
var key = Symmetric_AES.GenerateRandomKey(keySize);
byte[] input = GetRandomBytes(1000, 5000);
byte[] encrypted;
using (var algorithm = new Symmetric_AES_CBC())
{
encrypted = algorithm.EncryptBytes(input, key);
}
key = Symmetric_AES.GenerateRandomKey(keySize);
using (var algorithm = new Symmetric_AES_CBC())
{
algorithm.DecryptBytes(encrypted, key);
}
}
public void TestSameInputProducesDifferentOutput(Symmetric_AES.KeySize keySize)
{
var key = Symmetric_AES.GenerateRandomKey(keySize);
for (int counter = 0; counter < 10; ++counter)
{
var encryptedAsBase64 = new HashSet <string>();
using (var algorithm = new Symmetric_AES_CBC())
{
var inputBytes = GetRandomBytes(1024, 4096);
for (int i = 0; i < 100; ++i)
{
encryptedAsBase64.Add(Convert.ToBase64String(algorithm.EncryptBytes(inputBytes, key)));
}
}
Assert.AreEqual(100, encryptedAsBase64.Count, "Should be 100 distinct values");
}
}