public void TestSignature(ElipticCurve curve, int iterations)
{
ECKeysGenerator keyGen = new ECKeysGenerator(curve);
ECSignature signature = new ECSignature(curve);
for (int i = 0; i < iterations; i++)
{
Console.WriteLine($"signature curve {curve.Name} test {i}... ");
//generovanie klucoveho paru
byte[] privateKey1;
byte[] publicKey1;
keyGen.GenerateKeyPair(out privateKey1, out publicKey1);
byte[] privateKey2;
byte[] publicKey2;
keyGen.GenerateKeyPair(out privateKey2, out publicKey2);
string str1 = RandomString(random.Next(100));
string str2 = RandomString(random.Next(100));
while (str1 == str2)
{
str2 = RandomString(random.Next(100));
}
byte[] sign1 = signature.Signature(str1, privateKey1);
byte[] sign2 = signature.Signature(str2, privateKey1);
Console.WriteLine(Convert.ToBase64String(sign1));
if (!signature.VerifySignature(str1, sign1, publicKey1))
{
Write($"Signature should be valid !!! ", ConsoleColor.Red);
throw new Exception("Fatal error");
}
if (signature.VerifySignature(str1, sign1, publicKey2))
{
Write($"Signature should not be valid because of wrong public key !!!", ConsoleColor.DarkYellow);
}
if (signature.VerifySignature(str2, sign1, publicKey1))
{
Console.WriteLine();
Write($"Signature should not be valid because of changed message!!!", ConsoleColor.DarkYellow);
}
else
{
Write("OK", ConsoleColor.Green);
}
}
}
/// <summary>
/// - Gets specific encrypted source file from server.
/// - Encryption and Decription using AES symetric and commonSecret derived from EC Diffie-Helman key Exchange
/// - Decrypts source files
/// - verifies digital signature of source code
/// </summary>
/// <param name="sourceFileInfo">the file to get</param>
/// <returns>verified and decrypted source file or null if operation unsuccessfull</returns>
private string DecryptSourceFromServer(SourceFileInfo sourceFileInfo)
{
byte[] dhClientPublic;
byte[] dhClientPrivate;
_keyGen.GenerateKeyPair(out dhClientPrivate, out dhClientPublic);
string uri = (TroubleShooterClient.SERVICE_PATH + "/source");
ProtectedSourceRequest request = new ProtectedSourceRequest()
{
DhClientPublic = dhClientPublic, FileName = sourceFileInfo.FileName
};
HttpResponseMessage response = _client.PostAsJsonAsync(uri, request).GetAwaiter().GetResult();
if (response.IsSuccessStatusCode)
{
ProtectedSource source = response.Content.ReadAsAsync <ProtectedSource>().GetAwaiter().GetResult();
byte[] sharedSecret = _diffieHelman.SharedSecret(dhClientPrivate, source.DhPublicServer);
string decryptedSource = AesHandler.DecryptStringFromBytes_Aes(source.SourceCode, sharedSecret);
if (_verifier.VerifySignature(decryptedSource, source.Signature, _signatureKey))
{
return(decryptedSource);
}
else
{
return(null);
}
}
return(null);
}