public static void Encrypt(int bitsKeyLength, TestPrimeDelegate testPrime, string inputFilePath,
string sourceFilePath, string publicKeyFilePath, string privateKeyFilePath)
{
var bytesKeyLength = bitsKeyLength / 8;
var p = GenerateLargePrimeNumber(bytesKeyLength, testPrime);
var q = GenerateLargePrimeNumber(bytesKeyLength, testPrime);
var n = p * q;
var phiN = EulerFunction(p, q);
Debug.Assert(Gcd(PublicExponent, phiN).IsOne);
// calculate d
BigInteger d, tmp;
var g = Gcd(PublicExponent, phiN, out d, out tmp);
d = (d % phiN + phiN) % phiN;
Console.WriteLine("Writing public key to " + publicKeyFilePath);
WriteKeyToFile(n, publicKeyFilePath);
Console.WriteLine("Writing private key to " + privateKeyFilePath);
WriteKeyToFile(d, privateKeyFilePath);
Console.WriteLine("Writing encrypted data to " + DefaultEncryptedFileName);
using (var reader = File.OpenRead(Path.GetFullPath(DefaultSourceFileName))) {
using (var writer = File.CreateText(Path.GetFullPath(DefaultEncryptedFileName))) {
int b;
var first = true;
while ((b = reader.ReadByte()) != -1)
{
if (!first)
{
writer.Write(Delimeter);
}
else
{
first = false;
}
var encryptedBytes = BinPowMod(b, PublicExponent, n);
writer.Write(encryptedBytes.ToString());
}
}
}
}
private static BigInteger GenerateLargePrimeNumber(int bytesLength, TestPrimeDelegate testPrime)
{
while (true)
{
var candidate = GenerateRandomNumber(bytesLength);
while (candidate <= 2)
{
candidate = GenerateRandomNumber(bytesLength);
}
// make odd
candidate |= 1;
if (testPrime(candidate))
{
return(candidate);
}
}
}
