public void TestDiffusionTest()
{
// since we flip one bit in the plain text, the least diffusion
// we can get is one bit changed. e.g. flips 1 / (1024*8 bits)
// (e.g.: 1 flip / plain-length in bits)
// The score is matched against 50% bit flips. 0% means cypher == plain
// and 100% cypher == !plain, so the best result is closest to random 50%
// Hence: (50% - |50% - flips%|) / 50%
//const float EXPECTED_MIN = 0.000244140625f;
Log.Info("Diffusion: Measure of variance due to a change in the plain text");
float calc_min = 1f / (1024f * 8f);
calc_min = (0.5f - Math.Abs(0.5f - calc_min)) / 0.5f;
var tested = GetTestCases();
foreach (var t in tested)
{
if (t.ExpectedVal.HasValue && t.ExpectedVal == 0)
{
t.ExpectedVal = calc_min;
}
}
using (Log.StartIndentScope())
for (int b = 0; b < 4; b++)
{
EncryptionTesting.Type = (EncryptionTesting.TextType)b;
Log.Info($"Text Type: {EncryptionTesting.Type}");
using (Log.StartIndentScope())
foreach (var test in tested)
{
float res = EncryptionTesting.TestForDifussion(test.Cypher, 10);
Log.Info($"{test.Name} score for Diffusion {res}");
if (test.ExpectedVal != null)
{
Assert.IsTrue(Math.Abs(res - test.ExpectedVal.Value) < 0.000001, test.Name + " should score zero for Diffusion");
}
}
}
}
public void TestConfusionTest()
{
Log.Info("Confusion: Measure of variance due to key");
var tested = GetTestCases();
using (Log.StartIndentScope())
foreach (EncryptionTesting.TextType val in Enum.GetValues(typeof(EncryptionTesting.TextType)))
{
EncryptionTesting.Type = val;
Log.Info($"Text Type: {EncryptionTesting.Type}");
using (Log.StartIndentScope())
foreach (var test in tested)
{
float res = EncryptionTesting.TestForConfusion(test.Cypher, 10);
Log.Info($"{test.Name} score for Confusion {res}");
if (test.ExpectedVal != null)
{
Assert.IsTrue(Math.Abs(res - test.ExpectedVal.Value) < float.Epsilon, test.Name + " should score zero for confusion");
}
}
}
}
public void TestDistributionTest()
{
Log.Info("Distribution: Measure of uniform distribution");
var tested = GetTestCases();
using (Log.StartIndentScope())
for (int b = 0; b < 4; b++)
{
EncryptionTesting.Type = (EncryptionTesting.TextType)b;
Log.Info($"Text Type: {EncryptionTesting.Type}");
using (Log.StartIndentScope())
foreach (var test in tested)
{
float res = EncryptionTesting.TestForDistribution(test.Cypher);
Log.Info($"{test.Name} score for distribution {res}");
if (test.ExpectedVal != null)
{
Assert.IsTrue(Math.Abs(res - test.ExpectedVal.Value) < float.Epsilon, test.Name + " should score zero for distribution");
}
}
}
}
