public byte[] Decrypt(String str)
{
ArrayList resultSet = new ArrayList();
BigInteger2[] message = splitMessage(Convert.FromBase64String(str), n, "decrypt");
GC.Collect();
for (int i = 0; i < message.Length; i++)
{
//message[i] = BigInteger2.NegateZeros(message[i]);
BigInteger2 unitResult = BigIntegerExtensions.modPower(message[i], d, Mod);
unitResult = BigInteger2.NegateZeros(unitResult);
BigInteger2 result = new BigInteger2(unitResult.bitlength.Length - 3, 0);
for (int x = 3, xj = 2; x < unitResult.bitlength.Length; x++, xj++)
{
result.bitlength[xj] = unitResult.bitlength[x];
}
unitResult = result;
resultSet.Add(unitResult);
GC.Collect();
}
//Create Full BigInteger2 containing bits from resultSet BigIntegers
int bitSize = 0;
foreach (BigInteger2 b in resultSet)
{
bitSize += (b.bitlength.Length - 2);
}
//MessageBox.Show("Whole decrypted Text length: " + bitSize);
BigInteger2 wholeMessage = new BigInteger2(bitSize, 0);
//Fill wholeMessage
int curIndex = 2;
foreach (BigInteger2 b in resultSet)
{
for (int i = 2; i < b.bitlength.Length; i++, curIndex++)
{
wholeMessage.bitlength[curIndex] = b.bitlength[i];
}
}
byte[] res = DeInject(wholeMessage);
GC.Collect();
// MessageBox.Show("Decryption Completed!!!");
return(res);
}
public byte[] Encrypt(String str)
{
BigInteger2[] message = this.splitMessage(Encoding.UTF8.GetBytes(str), this.n - 1, "encrypt");
mess = new BigInteger2[message.Length];
mess = message;
//MessageBox.Show("Message Length: " + message.Length);
//return data;
ArrayList resultSet = new ArrayList();
GC.Collect();
//Encrypt each Message and populate resultSet
for (int i = 0; i < message.Length; i++)
{
BigInteger2 unitResult = BigIntegerExtensions.modPower(message[i], e, Mod);
unitResult = BigInteger2.NegateZeros(unitResult);
if (i == 0 && unitResult.bitlength.Length - 2 < n)
{
//MessageBox.Show("Padding with 'a'");
int ind = n + 4 - unitResult.bitlength.Length;
BigInteger2 tmp = new BigInteger2(n, 0);
for (int xi = ind, xj = 2; xj < unitResult.bitlength.Length; xi++, xj++)
{
tmp.bitlength[xi] = unitResult.bitlength[xj];
}
unitResult = tmp;
//PAD Left with byte 'a'
byte[] pad = ASCIIEncoding.ASCII.GetBytes("a");
BitArray padAry = new BitArray(pad);
//PAD left of unitResult with padAry
BigInteger2 padded = new BigInteger2(unitResult.bitlength.Length - 2 + padAry.Length, 0);
int pi, pj;
for (pi = 2, pj = 0; pj < padAry.Length; pi++, pj++)
{
padded.bitlength[pi] = padAry[pj];
}
//Continue filling from unitResult
for (int indi = pi, indj = 2; indi < padded.bitlength.Length; indi++, indj++)
{
padded.bitlength[indi] = unitResult.bitlength[indj];
}
unitResult = padded;
}
if (i > 0 && unitResult.bitlength.Length - 2 < n)
{
//MessageBox.Show("Padding with zeros");
//pad result's leftside with zeros
int ind = n + 4 - unitResult.bitlength.Length;
BigInteger2 tmp = new BigInteger2(n, 0);
for (int xi = ind, xj = 2; xj < unitResult.bitlength.Length; xi++, xj++)
{
tmp.bitlength[xi] = unitResult.bitlength[xj];
}
unitResult = null;
unitResult = tmp;
}
GC.Collect();
resultSet.Add(unitResult);
}
//Create Full BigInteger2 containing bits from resultSet BigIntegers
int bitSize = 0;
foreach (BigInteger2 b in resultSet)
{
bitSize += (b.bitlength.Length - 2);
}
BigInteger2 wholeMessage = new BigInteger2(bitSize, 0);
//Fill wholeMessage
int curIndex = 2;
foreach (BigInteger2 b in resultSet)
{
for (int i = 2; i < b.bitlength.Length; i++, curIndex++)
{
wholeMessage.bitlength[curIndex] = b.bitlength[i];
}
}
byte[] result = BigInteger2.getKeyBytes(wholeMessage);
GC.Collect();
// MessageBox.Show("Encryption Completed!!!");
return(result);
}
//MillerRabinTest
public static bool MillerRabinIsPrime(BigInteger2 numb)
{
//Use Rabin's Test suite a.modPower(d,numb)== 1 : then numb is prime else numb composite
BigInteger2 n = (BigInteger2)numb.Clone();
BigInteger2 numbLess1 = n - BigInteger2.ONE();
BigInteger2[] testSuite = new BigInteger2[3];
//Fill testSuite with BigInteger2 values:
//Including 5, 11, and 61
testSuite[0] = new BigInteger2(1, 0);
testSuite[0].bitlength = BigInteger2.ConvertToBinary(61, 6);
testSuite[1] = new BigInteger2(1, 0);
testSuite[1].bitlength = BigInteger2.ConvertToBinary(31, 6);
testSuite[2] = new BigInteger2(1, 0);
testSuite[2].bitlength = BigInteger2.ConvertToBinary(11, 4);
// Determine two.power(r) factor of q:
// By: using q is least set bit referenced from zero
int i = 0, j = 0;
for (i = numbLess1.bitlength.Length - 1, j = 0; i >= 2; i--, j++)
{
if (numbLess1.bitlength[i])
{
break;
}
}
//Console.Out.WriteLine("j: {0}", j.ToString());
//Form component two.power(r) = twoPowerR
BigInteger2 twoPowerS = BigInteger2.TWO().power(j);
//Calculate d:
BigInteger2 d = BigIntegerExtensions.DivideBy(numbLess1, twoPowerS)[0];
//Use testSuite to eliminate Composites:
bool isPrime = true;
foreach (BigInteger2 integer in testSuite)
{
bool prime = false;
BigInteger2 result = BigIntegerExtensions.modPower(integer, d, numb);
if (result == BigInteger2.ONE())
{
prime = true;
continue;
}
else
{
for (i = 0; i < j; i++)
{
if ((numb - result) == BigInteger2.ONE())
{
prime = true;
break;
}
result = BigIntegerExtensions.modPower(result, BigInteger2.TWO(), numb);
}
if (prime)
{
continue;
}
else
{
isPrime = false;
break;
}
}
}
return(isPrime);
}
