public void InitDiffieHellman_ShouldGenerateSameDerivedKeys() //imitating client to test encrypting
{
ECDiffieHellmanCng eCDiffie = new ECDiffieHellmanCng(256);
eCDiffie.KeyDerivationFunction = ECDiffieHellmanKeyDerivationFunction.Hash;
eCDiffie.HashAlgorithm = CngAlgorithm.Sha256;
byte[] myPublicKey = eCDiffie.ExportSubjectPublicKeyInfo(); //export in x509 format
String myPublicKeyBase64 = Convert.ToBase64String(myPublicKey);
//Passing to project
var packetToPreoject = new Packet('0', Convert.ToBase64String(Encoding.ASCII.GetBytes(String.Concat("{", String.Format("\"Public_key\": \"{0}\"", myPublicKeyBase64), "}"))));
ServiceProcessor.UserLoggedIn stubMethod = StubMethod;
PacketProcessor packetProcessor = new PacketProcessor(stubMethod);
Packet response = packetProcessor.Process(packetToPreoject);
PublicKeyPayload serverPublicKey = JsonSerializer.Deserialize <PublicKeyPayload>(Convert.FromBase64String(response.Payload));
byte[] otherKeyFromBase64 = Convert.FromBase64String(serverPublicKey.Public_key);
ECDiffieHellmanCng eCDiffie2 = new ECDiffieHellmanCng(256);
eCDiffie2.KeyDerivationFunction = ECDiffieHellmanKeyDerivationFunction.Hash;
eCDiffie2.HashAlgorithm = CngAlgorithm.Sha256;
int some = 0;
eCDiffie2.ImportSubjectPublicKeyInfo(otherKeyFromBase64, out some);
byte[] otherKeyDecoded = eCDiffie2.PublicKey.ToByteArray();
CngKey k = CngKey.Import(otherKeyDecoded, CngKeyBlobFormat.EccPublicBlob);
byte[] derivedKey = eCDiffie.DeriveKeyMaterial(k);
string actual = Convert.ToBase64String(packetProcessor.EncryptionModule.DerivedKey);
string expected = Convert.ToBase64String(derivedKey);
Assert.Equal(expected, actual);
}
