// Generate RSA Keys function
public static long[] GenerateKeys(long p, long q, long e)
{
long[] result = new long[3];
long phi, n, d;
// calculate n and phi
n = p * q;
phi = (p - 1) * (q - 1);
long[] euclidOutput = new long[3];
// find d using extended Euclidean algorithm
euclidOutput = MathsProcessor.ExtEucAlg(e, phi);
d = euclidOutput[1];
// set results to array
result[0] = n;
result[1] = phi;
result[2] = d;
// If d is negative it's not suitable, therefore add phi. This will change value of v
// however the equation d*e - v*Ф = 1 will still hold
if (d < 0)
{
result[2] += phi;
}
return(result);
}
private void q2FactorizeBtn_Click(object sender, EventArgs e)
{
try
{
long inputNum = long.Parse(q2NumEntryTbx.Text); // error handling here
// get list of factors
List <long> resultList = MathsProcessor.PrimeFactorize(inputNum);
string resultString = "";
// add each number to string
foreach (var num in resultList)
{
resultString += num.ToString() + " ";
}
q2ResultRTbx.Text = resultString;
}
catch (FormatException frmtExcptn)
{
MessageBox.Show("Wrong number format. Please enter a correct number.");
}
catch (OverflowException oe)
{
MessageBox.Show("Entered number(s) is too big.");
}
}
private void q4Compute_Click(object sender, EventArgs e)
{
try
{
long numA = long.Parse(q4EntryATbox.Text); // error handling
long numB = long.Parse(q4EntryBTbox.Text); // -//-
long[] resultArray = MathsProcessor.ExtEucAlg(numA, numB);
string equation = string.Format("{0} = {1:+#;-#}a {2:+#;-#;}b", resultArray[0], resultArray[1], resultArray[2]);
q4EqtnOutTbox.Text = equation;
string gcd = resultArray[0].ToString();
string strX = resultArray[1].ToString();
string strY = resultArray[2].ToString();
q4GcdOutTbox.Text = gcd;
q4XOutTbox.Text = strX;
q4YOutTbox.Text = strY;
}
catch (FormatException fe)
{
MessageBox.Show("Wrong or missing input. Please enter a and b in a correct format.");
}
catch (OverflowException oe)
{
MessageBox.Show("Entered number(s) is too big.");
}
}
private void ApplyEuclidAlg()
{
using (StreamWriter sw = new StreamWriter(@"Q3.txt"))
{
sw.WriteLine("Q3.\n");
foreach (var pair in PairList)
{
sw.WriteLine("GCD({0}, {1}) = {2}", pair[0], pair[1], MathsProcessor.EuclidAlg(pair[0], pair[1]));
}
}
}
private static long GenerateE(long p, long q)
{
//calculate Ф(p,q)
long phi = (p - 1) * (q - 1);
// start at p-2
long candidateE = p - 2;
while (MathsProcessor.EuclidAlg(candidateE, phi) != 1 && MathsProcessor.PrimeCheck(candidateE) != 1)
{
--candidateE;
}
return(candidateE);
}
private void ApplyExtendedEuclidAlg()
{
using (StreamWriter sw = new StreamWriter(@"Q4.txt"))
{
sw.WriteLine("Q4.\n");
foreach (var pair in PairList)
{
// display a and b
sw.WriteLine("a = {0}, b = {1}", pair[0], pair[1]);
// get gcd, x and y
long[] result = MathsProcessor.ExtEucAlg(pair[0], pair[1]);
// write an equation. formatters used to show correct sign
sw.WriteLine("Equation: {1:+#;-#}a {2:+#;-#;}b = {0}", result[0], result[1], result[2]);
// display GCD
sw.WriteLine("GCD({0}, {1}) = {2}", pair[0], pair[1], result[0]);
// display coefficients
sw.WriteLine("x = {0}\ny = {1}\n", result[1], result[2]);
}
}
}
private void q3CalcGcdBtn_Click(object sender, EventArgs e)
{
try
{
long numA = long.Parse(q3EntryATbox.Text); // error handling
long numB = long.Parse(q3EntryBTbox.Text); // -//-
long gcd = MathsProcessor.EuclidAlg(numA, numB);
q3GcdOutLabel.Text = "The Greatest Common Divisor of " + numA + " and " + numB + " is " + gcd;
}
catch (FormatException fe)
{
MessageBox.Show("Wrong or missing input. Please enter a and b in a correct format.");
}
catch (OverflowException oe)
{
MessageBox.Show("Entered number(s) is too big.");
}
}
private void PrimeFactorizeNums()
{
List <long> numsList = GetNumsFromTbox();
using (StreamWriter sw = new StreamWriter(@"Q2.txt")) // modify file paths later
{
sw.WriteLine("Q2.\n");
foreach (var num in numsList)
{
List <long> factorList = MathsProcessor.PrimeFactorize(num);
sw.Write("The factors of {0} are: ", num);
foreach (var factor in factorList)
{
sw.Write(factor + " ");
}
sw.Write("\n");
}
}
}
private void q6DecryptBtn_Click(object sender, EventArgs e)
{
try
{
long cyphertext = long.Parse(q6CypherTbox.Text);
long decExp = long.Parse(q6DecryptExpTbox.Text);
long rsaMod = long.Parse(q6RsaModTbox.Text);
BigInteger message = MathsProcessor.RSADecrypt(cyphertext, decExp, rsaMod);
q6PlainTxtTbox.Text = message.ToString();
}
catch (FormatException fe)
{
MessageBox.Show("Wrong or missing input. Please fill all input fields in a correct number format.");
}
catch (OverflowException oe)
{
MessageBox.Show("Entered number(s) is too big.");
}
}
private void q5EncryptBtn_Click(object sender, EventArgs e)
{
try
{
long msg = long.Parse(q5MsgEntryTbox.Text); // error handling
long encExp = long.Parse(q5EncrExpTbox.Text);
long rsaMod = long.Parse(q5RsaModTbox.Text);
BigInteger cyphertext = MathsProcessor.RSAEncrypt(msg, encExp, rsaMod);
q5CypherTbox.Text = cyphertext.ToString();
}
catch (FormatException fe)
{
MessageBox.Show("Wrong or missing input. Please fill all input fields in a correct number format.");
}
catch (OverflowException oe)
{
MessageBox.Show("Entered number(s) is too big.");
}
}
private void PrimeCheckNums()
{
List <long> numsList = GetNumsFromTbox();
using (StreamWriter sw = new StreamWriter(@"Q1.txt")) // modify file paths later
{
sw.WriteLine("Q1.\n");
foreach (var num in numsList)
{
if (MathsProcessor.PrimeCheck(num) == 1)
{
sw.WriteLine("The number {0} is prime", num);
}
else
{
sw.WriteLine("The number {0} is NOT prime", num);
}
}
}
}
private void RSAGenerateBtn_Click(object sender, EventArgs e)
{
try
{
long p = long.Parse(EnterPTbox.Text); /// ERROR HANDLING HERE
long q = long.Parse(EnterQTbox.Text);
long exp;
// if forgot to input encryption exponent, generate it
if (EnterETbox.Text == "")
{
exp = GenerateE(p, q);
EnterETbox.Text = exp.ToString();
}
else
{
exp = long.Parse(EnterETbox.Text);
}
long[] keys = MathsProcessor.GenerateKeys(p, q, exp);
OutputNTbox.Text = keys[0].ToString();
OutputPhiTbox.Text = keys[1].ToString();
OutputDTbox.Text = keys[2].ToString();
parentForm.EncryptionExponent = exp.ToString();
parentForm.Q5RsaModulus = keys[0].ToString();
parentForm.Q6RsaModulus = keys[0].ToString();
parentForm.DecryptionExponent = keys[2].ToString();
}
catch (FormatException fe)
{
MessageBox.Show("Wrong or missing input. Please fill all input fields in a correct number format.");
}
catch (OverflowException oe)
{
MessageBox.Show("Entered number(s) is too big.");
}
}
private void q1CheckPrimeBtn_Click(object sender, EventArgs e)
{
try
{
long inputNum = long.Parse(q1NumEntryTbx.Text);
if (MathsProcessor.PrimeCheck(inputNum) == 1)
{
q1ResponseLabel.Text = "The number " + inputNum + " is prime";
}
else
{
q1ResponseLabel.Text = "The number " + inputNum + " is NOT prime";
}
}
catch (FormatException formatExcptn)
{
MessageBox.Show("Wrong number format. Please enter a correct number.");
}
catch (OverflowException oe)
{
MessageBox.Show("Entered number(s) is too big.");
}
}