/// <summary>
/// Calculates a MAC using the X9.19 algorithm.
/// </summary>
/// <param name="data">Hex data to MAC.</param>
/// <param name="key">MACing key.</param>
/// <param name="iv">Initial vector.</param>
/// <param name="blockType">Message block to MAC.</param>
/// <returns>MAC result.</returns>
public static string MacHexData(string data, HexKey key, string iv, IsoX919BlockType blockType)
{
if (data.Length % 16 != 0)
{
data = Iso9797Pad.PadHexString(data, Iso9797PaddingMethodType.PaddingMethod1);
}
for (var i = 0; i <= (data.Length / 16) - 1; i++)
{
iv = iv.XorHex(data.Substring(i * 16, 16));
iv = TripleDes.DesEncrypt(key.PartA, iv);
}
var result = iv;
if (blockType == IsoX919BlockType.FinalBlock || blockType == IsoX919BlockType.OnlyBlock)
{
result = TripleDes.DesDecrypt(key.PartB, iv);
result = TripleDes.DesEncrypt(key.PartA, result);
}
return(result);
}
public void TestByteDes(byte[] key, byte[] data, byte[] expected)
{
Assert.AreEqual(expected, TripleDes.DesEncrypt(key, data));
Assert.AreEqual(data, TripleDes.DesDecrypt(key, expected));
}