public void RSAEncryption()
{
BigInteger p = view.PrimeP, q = view.PrimeQ, e = view.E, d = 0;
view.WarningMessage = string.Empty;
if (p.ToString().Length > 7 || q.ToString().Length > 7 || e.ToString().Length > 7)
{
view.WarningMessage += "primenumbers with more than 7 Digits wont be checked,\nso your Encryption might be wrong";
try
{
d = MyMath.ModInverse(e, MyMath.PhiFuncPrime(p, q));
}
catch (DivideByZeroException exception)
{
view.WarningMessage += "\ntry different input values";
return;
}
}
else
{
//Checking if p and q are prime numbers
if (!MyMath.IsPrime(p))
{
UpdateWarningMessage("p is not prime");
return;
}
if (!MyMath.IsPrime(q))
{
UpdateWarningMessage("q is not prime");
return;
}
//checkign if e is relative prime to p * q
if (!((1 < e && e < MyMath.PhiFuncPrime(p, q)) && MyMath.GCD(e, MyMath.PhiFuncPrime(p, q)) == 1))
{
UpdateWarningMessage("e must be 1 < e < phi(p * q) and relative prime to p * q");
return;
}
//
if (p * q < 128)
{
UpdateWarningMessage("p * q must be bigger than 127");
return;
}
d = MyMath.ModInverse(e, MyMath.PhiFuncPrime(p, q));
}
RSAEncryption encryption = new RSAEncryption();
encryption.P = p;
encryption.Q = q;
encryption.E = e;
encryption.D = d;
view.PublicKey = $"({encryption.E}|{encryption.N})";
view.PrivateKey = $"({encryption.D}|{encryption.N})";
view.EncryptedMessage = encryption.Encryption(ASCIIEncoding.ASCII.GetBytes(view.Message));
view.DecryptedMessage = encryption.Decryption();
}
