protected virtual BigInteger CalculateGenerator_FIPS186_3_Verifiable(IDigest d, BigInteger p, BigInteger q, byte[] seed, int index)
{
BigInteger e = p.Subtract(BigInteger.One).Divide(q);
byte[] array = Hex.Decode("6767656E");
byte[] array2 = new byte[seed.Length + array.Length + 1 + 2];
Array.Copy(seed, 0, array2, 0, seed.Length);
Array.Copy(array, 0, array2, seed.Length, array.Length);
array2[array2.Length - 3] = (byte)index;
byte[] array3 = new byte[d.GetDigestSize()];
for (int i = 1; i < 65536; i++)
{
DsaParametersGenerator.Inc(array2);
DsaParametersGenerator.Hash(d, array2, array3);
BigInteger bigInteger = new BigInteger(1, array3);
BigInteger bigInteger2 = bigInteger.ModPow(e, p);
if (bigInteger2.CompareTo(BigInteger.Two) >= 0)
{
return bigInteger2;
}
}
return null;
}
protected virtual DsaParameters GenerateParameters_FIPS186_2()
{
byte[] array = new byte[20];
byte[] array2 = new byte[20];
byte[] array3 = new byte[20];
byte[] array4 = new byte[20];
int num = (this.L - 1) / 160;
byte[] array5 = new byte[this.L / 8];
if (!(this.digest is Sha1Digest))
{
throw new InvalidOperationException("can only use SHA-1 for generating FIPS 186-2 parameters");
}
BigInteger bigInteger;
int i;
BigInteger bigInteger4;
while (true)
{
this.random.NextBytes(array);
DsaParametersGenerator.Hash(this.digest, array, array2);
Array.Copy(array, 0, array3, 0, array.Length);
DsaParametersGenerator.Inc(array3);
DsaParametersGenerator.Hash(this.digest, array3, array3);
for (int num2 = 0; num2 != array4.Length; num2++)
{
array4[num2] = (array2[num2] ^ array3[num2]);
}
byte[] expr_B6_cp_0 = array4;
int expr_B6_cp_1 = 0;
expr_B6_cp_0[expr_B6_cp_1] |= 128;
byte[] expr_D0_cp_0 = array4;
int expr_D0_cp_1 = 19;
expr_D0_cp_0[expr_D0_cp_1] |= 1;
bigInteger = new BigInteger(1, array4);
if (bigInteger.IsProbablePrime(this.certainty))
{
byte[] array6 = Arrays.Clone(array);
DsaParametersGenerator.Inc(array6);
for (i = 0; i < 4096; i++)
{
for (int j = 0; j < num; j++)
{
DsaParametersGenerator.Inc(array6);
DsaParametersGenerator.Hash(this.digest, array6, array2);
Array.Copy(array2, 0, array5, array5.Length - (j + 1) * array2.Length, array2.Length);
}
DsaParametersGenerator.Inc(array6);
DsaParametersGenerator.Hash(this.digest, array6, array2);
Array.Copy(array2, array2.Length - (array5.Length - num * array2.Length), array5, 0, array5.Length - num * array2.Length);
byte[] expr_18F_cp_0 = array5;
int expr_18F_cp_1 = 0;
expr_18F_cp_0[expr_18F_cp_1] |= 128;
BigInteger bigInteger2 = new BigInteger(1, array5);
BigInteger bigInteger3 = bigInteger2.Mod(bigInteger.ShiftLeft(1));
bigInteger4 = bigInteger2.Subtract(bigInteger3.Subtract(BigInteger.One));
if (bigInteger4.BitLength == this.L && bigInteger4.IsProbablePrime(this.certainty))
{
goto Block_6;
}
}
}
}
Block_6:
BigInteger g = this.CalculateGenerator_FIPS186_2(bigInteger4, bigInteger, this.random);
return new DsaParameters(bigInteger4, bigInteger, g, new DsaValidationParameters(array, i));
}
protected virtual DsaParameters GenerateParameters_FIPS186_3()
{
IDigest digest = this.digest;
int num = digest.GetDigestSize() * 8;
int n = this.N;
byte[] array = new byte[n / 8];
int num2 = (this.L - 1) / num;
int n2 = (this.L - 1) % num;
byte[] array2 = new byte[digest.GetDigestSize()];
BigInteger bigInteger2;
int i;
BigInteger bigInteger7;
while (true)
{
this.random.NextBytes(array);
DsaParametersGenerator.Hash(digest, array, array2);
BigInteger bigInteger = new BigInteger(1, array2).Mod(BigInteger.One.ShiftLeft(this.N - 1));
bigInteger2 = BigInteger.One.ShiftLeft(this.N - 1).Add(bigInteger).Add(BigInteger.One).Subtract(bigInteger.Mod(BigInteger.Two));
if (bigInteger2.IsProbablePrime(this.certainty))
{
byte[] array3 = Arrays.Clone(array);
int num3 = 4 * this.L;
for (i = 0; i < num3; i++)
{
BigInteger bigInteger3 = BigInteger.Zero;
int j = 0;
int num4 = 0;
while (j <= num2)
{
DsaParametersGenerator.Inc(array3);
DsaParametersGenerator.Hash(digest, array3, array2);
BigInteger bigInteger4 = new BigInteger(1, array2);
if (j == num2)
{
bigInteger4 = bigInteger4.Mod(BigInteger.One.ShiftLeft(n2));
}
bigInteger3 = bigInteger3.Add(bigInteger4.ShiftLeft(num4));
j++;
num4 += num;
}
BigInteger bigInteger5 = bigInteger3.Add(BigInteger.One.ShiftLeft(this.L - 1));
BigInteger bigInteger6 = bigInteger5.Mod(bigInteger2.ShiftLeft(1));
bigInteger7 = bigInteger5.Subtract(bigInteger6.Subtract(BigInteger.One));
if (bigInteger7.BitLength == this.L && bigInteger7.IsProbablePrime(this.certainty))
{
goto Block_5;
}
}
}
}
Block_5:
if (this.usageIndex >= 0)
{
BigInteger bigInteger8 = this.CalculateGenerator_FIPS186_3_Verifiable(digest, bigInteger7, bigInteger2, array, this.usageIndex);
if (bigInteger8 != null)
{
return new DsaParameters(bigInteger7, bigInteger2, bigInteger8, new DsaValidationParameters(array, i, this.usageIndex));
}
}
BigInteger g = this.CalculateGenerator_FIPS186_3_Unverifiable(bigInteger7, bigInteger2, this.random);
return new DsaParameters(bigInteger7, bigInteger2, g, new DsaValidationParameters(array, i));
}