/// <summary>
/// Тест Миллера — Рабина на простоту
/// </summary>
/// <param name="n">Тестируемое число</param>
/// <param name="testCount">Колличество итераций проверки</param>
/// <returns></returns>
public static bool IsPrime(this BigInteger n, uint testCount = 20)
{
if (testCount < 10)
{
throw new ArgumentException("test count must be greater 10");
}
if (n.Sign != 1)
{
throw new ArgumentException("n must be positive");
}
if (n == 2)
{
return(true);
}
if (n.IsEven)
{
return(false);
}
ulong s = 0;
BigInteger t = n - 1;
while (t.IsEven)
{
s++;
t = t >> 1;
}
for (uint i = 0; i < testCount; i++)
{
BigInteger a = NumMethodsClass.GenerateBigInteger(2, n - 2);
BigInteger x = BigInteger.ModPow(a, t, n);
if ((x == BigInteger.One) || (x == (n - 1)))
{
continue;
}
for (ulong j = 0; j < (s - 1); j++)
{
x = BigInteger.ModPow(x, 2, n);
if (x == BigInteger.One)
{
return(false);
}
if (x == (n - 1))
{
break;
}
}
if (x != (n - 1))
{
return(false);
}
}
return(true);
}
private void RegenerateSizeParameters()
{
int keySize = NumMethodsClass.GetModuleSize(BigInteger.Parse(GeneralParameter));
_readingSize = keySize - 1;
_packingSize = keySize;
}
public void GenerateKey()
{
try
{
BigInteger p = NumMethodsClass.GeneratePrime(95);
BigInteger q = NumMethodsClass.GeneratePrime(98);
BigInteger modulus = p * q;
BigInteger phi = (p - 1) * (q - 1);
BigInteger pubExp = NumMethodsClass.GetPublicExponent(p.ToString(), q.ToString());;
BigInteger privateExponentInt = pubExp.Inverse(phi);
if (privateExponentInt == 0)
{
throw new ApplicationException();
}
_modulus = modulus.ToString();
_phi = phi.ToString();
_openExponent = pubExp.ToString();
_secretExponent = privateExponentInt.ToString();
RegenerateSizeParameters();
}
catch (Exception)
{
throw new ApplicationException("Error via generate key");
}
}
private void RegenerateSizeParameters()
{
string modulus = GeneralParameter.Split(" ")[0];
int keySize = NumMethodsClass.GetModuleSize(BigInteger.Parse(modulus));
_readingSize = keySize - 1;
_packingSize = keySize;
}
public byte[] Sign(IKey Key, byte[] hash)
{
byte[] hashBytes = hash;
if (Key.IsKeyValid(isSigning: true))
{
List <byte> result = new List <byte>();
string[] generalList = Key.GeneralParameter.Split(" ");
BigInteger p = BigInteger.Parse(generalList[0]);
BigInteger q = BigInteger.Parse(generalList[1]);
BigInteger g = BigInteger.Parse(generalList[2]);
BigInteger x = BigInteger.Parse(Key.SecretParameter);
BigInteger k = BigInteger.Zero;
BigInteger r = BigInteger.Zero;
do
{
k = NumMethodsClass.GenerateBigInteger(1, q - 1);
BigInteger temp = BigInteger.ModPow(g, k, p);
BigInteger.DivRem(temp, q, out r);
} while (r == 0);
int countOfBytes = hashBytes.Length; // calculate count of bytes in block
byte[] block = new byte[countOfBytes + 1];
Buffer.BlockCopy(hashBytes, 0, block, 0, countOfBytes);
BigInteger s = BigInteger.Zero;
BigInteger.DivRem(k.Inverse(q) * (new BigInteger(block) + x * r), q, out s);
if (s == BigInteger.Zero)
{
throw new ApplicationException("Generate keys again. Invalid keys");
}
byte[] tempResult = s.ToByteArray();
byte[] packingUnit = new byte[hashBytes.Length];
Buffer.BlockCopy(tempResult, 0, packingUnit, 0, Math.Min(tempResult.Length, hashBytes.Length)); //copy to packing block from result of ciphering
result.AddRange(packingUnit);
result.AddRange(r.ToByteArray());
return(result.ToArray());
}
else
{
throw new ApplicationException("Key is not valid");
}
}
public MainWindow()
{
Thread thread = new Thread(() =>
{
NumMethodsClass.LoadPyScript();
});
thread.Start();
InitializeComponent();
DataContext = new SignToolMainVM();
}
private ElgamalPrivateKey GetElgamalPrivateKey(ElgamalPublicParams param)
{
ElgamalPublicParams parameters = param;
ElgamalPrivateKey pk;
BigInteger x;
BigInteger y;
x = NumMethodsClass.GenerateBigInteger(2, parameters.Modulus - 1);
y = CalculateKeysByPowm(parameters.Generator, x, parameters.Modulus);
pk.X = x;
pk.Y = y;
return(pk);
}
public static BigInteger Inverse(this BigInteger a, BigInteger module)
{
var result = NumMethodsClass.GCDex(a, module);
if (result.d != BigInteger.One)
{
return(0);
}
BigInteger.DivRem(result.x, module, out result.x);
if (result.x.Sign == -1)
{
result.x += module;
BigInteger.DivRem(result.x, module, out result.x);
}
return(result.x);
}
public static DHPublicParams Generate(int decimalNubmerCount)
{
BigInteger min = BigInteger.Pow(10, decimalNubmerCount);
BigInteger max = BigInteger.Pow(10, decimalNubmerCount + 1);
BigInteger p;
BigInteger q;
while (true)
{
q = NumMethodsClass.GenerateBigInteger(min, max);
if (q.IsPrime())
{
p = (q << 1) + BigInteger.One;
if (p.IsPrime())
{
break;
}
}
}
BigInteger pMinusOne = p - 1;
BigInteger g;
do
{
g = NumMethodsClass.GenerateBigInteger(2, pMinusOne);
} while (BigInteger.ModPow(g, 2, p) == BigInteger.One ||
BigInteger.ModPow(g, q, p) == BigInteger.One);
DHPublicParams dHPublic;
dHPublic.Modulus = p;
dHPublic.Generator = g;
return(dHPublic);
}
public void GenerateKey()
{
BigInteger q = NumMethodsClass.GeneratePrimeByPython(160);
BigInteger p;
BigInteger b;
do
{
b = NumMethodsClass.GenerateBigInteger((1024 - 160) / 8);
p = b * q + 1;
} while (!p.IsPrime());
BigInteger g = BigInteger.Zero;
for (BigInteger i = 2; i < p - 1; i++)
{
g = BigInteger.ModPow(i, b, p);
if (g > 1)
{
break;
}
}
if (g == BigInteger.Zero)
{
throw new ApplicationException("Try generate again, error via generating G");
}
BigInteger x = NumMethodsClass.GenerateBigInteger(2, q - 1);
BigInteger y = BigInteger.ModPow(g, x, p);
GeneralParameter = $"{p.ToString()} {q.ToString()} {g.ToString()}";
OpenParameter = y.ToString();
SecretParameter = x.ToString();
RegenerateSizeParameters();
}
public byte[] Sign(IKey Key, byte[] hash)
{
byte[] hashBytes = hash;
List <byte> result = new List <byte>(hashBytes.Length);
if (!Key.IsKeyValid(isSigning: true))
{
throw new ApplicationException("Key is not valid");
}
try
{
int readSize = Key.ReadingSize;
int writeSize = Key.PackingSize;
BigInteger k;
string[] generalParameters = Key.GeneralParameter.Split(" ");
BigInteger modulus = BigInteger.Parse(generalParameters[0]);
BigInteger generator = BigInteger.Parse(generalParameters[1]);
BigInteger secret = BigInteger.Parse(Key.SecretParameter);
do
{
k = NumMethodsClass.GenerateBigInteger(2, modulus - 3);
} while (BigInteger.GreatestCommonDivisor(k, modulus - 1) != 1);
BigInteger r = BigInteger.ModPow(generator, k, modulus);
byte[] packedBlock = new byte[writeSize];
byte[] rBlock = r.ToByteArray(false);
Buffer.BlockCopy(rBlock, 0, packedBlock, 0, rBlock.Length);
result.AddRange(packedBlock);
for (int currentByte = 0; currentByte < hashBytes.Length; currentByte += readSize)
{
int byteCopyCount = Math.Min(readSize, hashBytes.Length - currentByte);
byte[] currentBlock = new byte[byteCopyCount + 1]; // Добавлен 0х00 чтобы число было положительным
Buffer.BlockCopy(hashBytes, currentByte, currentBlock, 0, byteCopyCount);
BigInteger h = new BigInteger(currentBlock);
BigInteger temp;
BigInteger.DivRem(secret * r, modulus - 1, out temp);
BigInteger u;
BigInteger.DivRem(h - temp + (modulus - 1), modulus - 1, out u);
BigInteger s;
BigInteger.DivRem(k.Inverse(modulus - 1) * u, modulus - 1, out s);
byte[] cipherBlock = s.ToByteArray(false);
packedBlock = new byte[writeSize];
Buffer.BlockCopy(cipherBlock, 0, packedBlock, 0, cipherBlock.Length);
result.AddRange(packedBlock);
}
}
catch (Exception ex)
{
throw new Exception(ex.Message);
}
return(result.ToArray());
}