public void MaximumExceeded()
{
const string longSecret =
"-----BEGIN EC PRIVATE KEY-----MIIBUQIBAQQgxq7AWG9L6uleuTB9q5FGqnHjXF+kD4y9154SLYYKMDqggeMwgeACAQEwLAYHKoZIzj0BAQIhAP////////////////////////////////////7///wvMEQEIAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAABCAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAABwRBBHm+Zn753LusVaBilc6HCwcCm/zbLc4o2VnygVsW+BeYSDradyajxGVdpPv8DhEIqP0XtEimhVQZnEfQj/sQ1LgCIQD////////////////////+uq7c5q9IoDu/0l6M0DZBQQIBAaFEA0IABE0XO6I8lZYzXqRQnHP/knSwLex7q77g4J2AN0cVyrADicGlUr6QjVIlIu9NXCHxD2i++ToWjO1zLVdxgNJbUUc=-----END EC PRIVATE KEY-----";
var split = new ShamirsSecretSharing <BigInteger>(new ExtendedEuclideanAlgorithm <BigInteger>());
var combine = new ShamirsSecretSharing <BigInteger>(new ExtendedEuclideanAlgorithm <BigInteger>());
var shares = split.MakeShares(3, 7, longSecret, 1024);
var subSet1 = shares.Where(p => p.X.IsEven).ToList();
var recoveredSecret1 = combine.Reconstruction(subSet1.ToArray());
var subSet2 = shares.Where(p => !p.X.IsEven).ToList();
var recoveredSecret2 = combine.Reconstruction(subSet2.ToArray());
Assert.Equal(longSecret, recoveredSecret1);
Assert.Equal(longSecret, recoveredSecret2);
}
public void ReconstructionFailsAtRnd(int byteArraySize)
{
int ok = 0;
const int total = 1000;
var sss = new ShamirsSecretSharing <BigInteger>(new ExtendedEuclideanAlgorithm <BigInteger>());
var rng = new Random();
for (int i = 0; i < total; i++)
{
var message = new byte[byteArraySize];
rng.NextBytes(message);
const int n = 5;
var s = Convert.ToBase64String(message);
var secret = new Secret <BigInteger>(s);
var shares = sss.MakeShares((n + 1) / 2, n, secret);
var reconstructed =
Convert.FromBase64String(sss.Reconstruction(shares.Take((n + 1) / 2).ToArray())
.ToBase64());
if (message.SequenceEqual(reconstructed))
{
ok++;
}
}
Assert.Equal(1.0, (double)ok / total);
}
public void TestReconstructFromStringArray()
{
var combine = new ShamirsSecretSharing <BigInteger>(new ExtendedEuclideanAlgorithm <BigInteger>());
var secret = combine.Reconstruction(TestData.GetPredefinedShares());
Assert.Equal(TestData.DefaultTestPassword, secret);
}
public void TestMinimumSharedSecretsReconstruction()
{
var sss = new ShamirsSecretSharing <BigInteger>(new ExtendedEuclideanAlgorithm <BigInteger>());
var shares = sss.MakeShares(2, 7, 13);
var subSet = shares.Where(p => p.X == Calculator <BigInteger> .One).ToList();
Assert.Throws <ArgumentOutOfRangeException>(() => sss.Reconstruction(subSet.ToArray()));
}
public void TestShareThreshold()
{
var sss = new ShamirsSecretSharing <BigInteger>(new ExtendedEuclideanAlgorithm <BigInteger>());
var shares = sss.MakeShares(3, 7, 51);
var subSet = shares.Take(2).ToList();
var secret = sss.Reconstruction(subSet.ToArray());
Assert.NotEqual(shares.OriginalSecret, secret);
}
public void TestWithRandomSecret(int splitSecurityLevel, int expectedSecurityLevel)
{
var split = new ShamirsSecretSharing <BigInteger>(new ExtendedEuclideanAlgorithm <BigInteger>());
var combine = new ShamirsSecretSharing <BigInteger>(new ExtendedEuclideanAlgorithm <BigInteger>());
var shares = split.MakeShares(3, 7, splitSecurityLevel);
Assert.True(shares.OriginalSecretExists);
Assert.NotNull(shares.OriginalSecret);
var secret = shares.OriginalSecret;
var subSet1 = shares.Where(p => p.X.IsEven).ToList();
var recoveredSecret1 = combine.Reconstruction(subSet1.ToArray());
var subSet2 = shares.Where(p => !p.X.IsEven).ToList();
var recoveredSecret2 = combine.Reconstruction(subSet2.ToArray());
Assert.Equal(secret, recoveredSecret1);
Assert.Equal(secret, recoveredSecret2);
Assert.Equal(expectedSecurityLevel, split.SecurityLevel);
}
public void TestSecurityLevelAutoDetection(object secret, int expectedSecurityLevel)
{
var split = new ShamirsSecretSharing <BigInteger>(new ExtendedEuclideanAlgorithm <BigInteger>());
var combine = new ShamirsSecretSharing <BigInteger>(new ExtendedEuclideanAlgorithm <BigInteger>());
Shares <BigInteger> shares = null;
switch (secret)
{
case string password:
shares = split.MakeShares(3, 7, password);
break;
case BigInteger number:
shares = split.MakeShares(3, 7, number);
break;
case null:
return;
}
Assert.NotNull(shares);
Assert.True(shares.OriginalSecretExists);
Assert.NotNull(shares.OriginalSecret);
var subSet1 = shares.Where(p => p.X.IsEven).ToList();
var recoveredSecret1 = combine.Reconstruction(subSet1.ToArray());
var subSet2 = shares.Where(p => !p.X.IsEven).ToList();
var recoveredSecret2 = combine.Reconstruction(subSet2.ToArray());
switch (secret)
{
case string password:
Assert.Equal(password, recoveredSecret1);
break;
case BigInteger number:
Assert.Equal(number, (BigInteger)recoveredSecret1);
break;
}
Assert.Equal(shares.OriginalSecret, recoveredSecret1);
Assert.Equal(shares.OriginalSecret, recoveredSecret2);
Assert.Equal(expectedSecurityLevel, split.SecurityLevel);
}
public static string combineSharedSecrets(List <string> secrets)
{
List <FinitePoint <BigInteger> > points = new List <FinitePoint <BigInteger> >();
foreach (var secret in secrets)
{
points.Add(FinitePoint <BigInteger> .Parse(secret));
}
var combine = new ShamirsSecretSharing <BigInteger>(gcd);
return(combine.Reconstruction(points.ToArray()).ToString());
}
public void TestReconstructFromString()
{
StringBuilder sharesChunk = new StringBuilder();
foreach (var share in TestData.GetPredefinedShares())
{
sharesChunk.AppendLine(share);
}
var combine = new ShamirsSecretSharing <BigInteger>(new ExtendedEuclideanAlgorithm <BigInteger>());
var secret = combine.Reconstruction(sharesChunk.ToString());
Assert.Equal(TestData.DefaultTestPassword, secret);
}
public void TestReconstructFromStringArrayLegacy()
{
Secret.LegacyMode.Value = true;
try
{
var combine = new ShamirsSecretSharing <BigInteger>(new ExtendedEuclideanAlgorithm <BigInteger>());
var secret = combine.Reconstruction(TestData.GetPredefinedSharesLegacy());
Assert.Equal(TestData.DefaultTestPassword, secret);
}
finally
{
Secret.LegacyMode.Value = false;
}
}