public void EmptyKeyValueThrowsInvalidOperationException()
{
var credential = new Credential(() => new byte[0], SymmetricAlgorithm.Aes, 16);
Action getKey = () => credential.GetKey();
getKey.ShouldThrow <InvalidOperationException>().WithMessage("The value returned from the key function must not be null or empty.");
}
public void CanGetKey()
{
var credential = new Credential(
() => Convert.FromBase64String("1J9Og / OaZKWdfdwM6jWMpvlr3q3o7r20xxFDN7TEj6s="), SymmetricAlgorithm.Aes, 16);
var key = credential.GetKey();
key.Should().NotBeNull();
key.Length.Should().BeGreaterThan(0);
}
/// <summary>
/// Decrypts the specified cipher text.
/// </summary>
/// <param name="cipherText">The cipher text.</param>
/// <returns>The decrypted value as a byte array.</returns>
public byte[] Decrypt(byte[] cipherText)
{
if (cipherText is null)
{
throw new ArgumentNullException(nameof(cipherText));
}
if (!cipherText.IsEncrypted())
{
return(cipherText);
}
var decrypted = new List <byte>(cipherText.Length);
using (var stream = new MemoryStream(cipherText))
{
var decryptor = _algorithm.CreateDecryptor(
_credential.GetKey(), stream.ReadIVFromCipherTextHeader());
using var cryptoStream = new CryptoStream(stream, decryptor, CryptoStreamMode.Read);
const int bufferSize = 256;
var buffer = new byte[bufferSize];
while (true)
{
var readBytes = cryptoStream.Read(buffer, 0, buffer.Length);
if (readBytes > 0)
{
decrypted.AddRange(buffer.Take(readBytes));
}
else
{
break;
}
}
}
return(decrypted.ToArray());
}
