我非常擅长加密和使用BigIngeger值，并且一直致力于基于RSA的加密系统。 keygen方法和类工作正常以及加密方法，但解密方法拒绝解码输入的值。我意识到我可能错过了一个明显的错误，但任何帮助都会受到赞赏。
主：
package MAE;
import java.util.Scanner;
import java.lang.Math;
import java.math.BigInteger;
public class Main
{
public static void main(String[] args)
{
Scanner Input = new Scanner(System.in);
int choice;
boolean exit = true;
while(exit == true)
{
System.out.println("Please select a option from the menu below.");
System.out.println("1. Generate Key");
System.out.println("2. Encrypt Message");
System.out.println("3. Decrypt Message");
System.out.println("4. Exit");
choice = Input.nextInt();
switch(choice)
{
case 1:
keyGen();
break;
case 2:
encrypt();
break;
case 3:
decrypt();
break;
case 4:
exit = false;
break;
}
}
}
public static void keyGen()
{
Scanner Input = new Scanner(System.in);
encryptionAlgorithm eKey = new encryptionAlgorithm();
System.out.println("Public Key-(" + eKey.getEValue() + ", " + eKey.getNValue() + ")");
System.out.println("Private Key-(" + eKey.getDValue() + ", " + eKey.getNValue() + ")");
}
public static void encrypt()
{
String alphabet[] = new String[] {"a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z", ".", " "};
Scanner Input =new Scanner(System.in);
System.out.println("Enter Encryption Key First Number:");
BigInteger eKey1 = Input.nextBigInteger();
System.out.println("Enter Encryption Key Second Number");
BigInteger eKey2 = Input.nextBigInteger();
Input.nextLine();
System.out.println("Enter message to Encrypt, omitting any puncuation besides periods.");
String message = Input.nextLine().toLowerCase();
String messageChars[] = new String[message.length()];
BigInteger messageValues[] = new BigInteger[message.length()];
double previousValue = 0;
BigInteger messageEncrypted[] = new BigInteger[message.length()];
for(int x = 0; x < message.length(); x++)
{
messageChars[x] = Character.toString(message.charAt(x));
}
for(int x = 0; x < message.length(); x++)
{
for(int y = 0; y < alphabet.length; y++)
{
if(messageChars[x].equals(alphabet[y]))
{
messageValues[x] = BigInteger.valueOf(y + 5);
}
}
}
for(int x = 0; x < messageValues.length; x++)
{
messageEncrypted[x] = messageValues[x].modPow(eKey1, eKey2).add(BigInteger.valueOf((long) previousValue));
previousValue = ((messageValues[x].intValue() - 1) * (messageValues[x].intValue() + 1)) % messageValues[x].intValue();
}
for(int x = 0; x < messageEncrypted.length; x++)
{
System.out.print(messageEncrypted[x] + ", ");
}
}
public static void decrypt()
{
Scanner Input = new Scanner(System.in);
String alphabet[] = new String[] {"a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z", ".", " "};
System.out.println("Enter decryption key first number.");
int dKey1 = Input.nextInt();
System.out.println("Enter decryption key second number.");
int dKey2 = Input.nextInt();
Input.nextLine();
System.out.println("Enter message as numbers seperated by a '-'.");
String messageWhole = Input.nextLine();
String messageSegmented[] = messageWhole.split("-");
int messageValues[] = new int[messageSegmented.length];
int previousValue = 0;
for(int x = 0; x < messageSegmented.length; x++)
{
messageValues[x] = Integer.parseInt(messageSegmented[x]);
}
BigInteger tempval = new BigInteger("0");
int plaintextValues[] = new int[messageSegmented.length];
String plaintext[] = new String[messageSegmented.length];
for(int x = 0; x < messageValues.length; x++)
{
tempval = BigInteger.valueOf(messageValues[x]);
tempval = tempval.modPow(BigInteger.valueOf(dKey1), BigInteger.valueOf(dKey2));
plaintextValues[x] = tempval.intValue() - previousValue;
previousValue = plaintextValues[x];
}
for(int x = 0; x < plaintextValues[x]; x++)
{
System.out.print(plaintextValues[x]);
}
for(int x = 0; x < plaintextValues[x]; x++)
{
System.out.print(alphabet[plaintextValues[x]]);
}
}
}
encryptionAlgorithm：
package MAE;
import java.util.Scanner;
import java.util.Random;
public class encryptionAlgorithm
{
public static double p;
public static double q;
public static double n;
public static double r;
public static double k;
public static double eKey;
public static double dKey;
public encryptionAlgorithm()
{
Random random = new Random();
boolean isPPrime = true;
boolean isQPrime = true;
double d = 2;
Scanner Input = new Scanner(System.in);
System.out.println("Please enter a prime number. Larger numbers are more secure.");
p = Input.nextDouble();
do
{
isPPrime = true;
for(d = 2; d * d <= p && isPPrime == true; d++)
{
if(p % d == 0)
{
isPPrime = false;
}
}
if(isPPrime == false)
{
System.out.println("This number is not prime. Please enter another number.");
p = Input.nextDouble();
}
} while(isPPrime == false);
d = 2;
System.out.println("Please enter another prime number. Larger numbers are more secure.");
q = Input.nextDouble();
do
{
while(q == p)
{
System.out.println("This number is identical to the first entered number. Please enter another number.");
q = Input.nextDouble();
}
isQPrime = true;
for(d = 2; d * d <= q && isQPrime == true; d++)
{
if(q % d == 0)
{
isQPrime = false;
}
}
if(isQPrime == false)
{
System.out.println("This number is not prime. Please enter another number.");
q = Input.nextDouble();
}
} while(isQPrime == false);
n = p * q;
r = (p - 1) * (q - 1);
int randPrime = random.nextInt(5);
int x = 4;
int primeCounter = 0;
while(primeCounter < randPrime)
{
if(isPrime(x) == true)
{
primeCounter++;
}
x++;
}
x--;
eKey = x;
while((x * dKey) % r != 1)
{
dKey++;
System.out.println(dKey);
}
}
public boolean isPrime(int y)
{
for(int x = 2; x * x <= y; x++)
{
if(y % x == 0)
{
return false;
}
}
return true;
}
public double getPValue()
{
return p;
}
public double getQValue()
{
return q;
}
public double getNValue()
{
return n;
}
public double getRValue()
{
return r;
}
public double getKValue()
{
return k;
}
public double getEValue()
{
return eKey;
}
public double getDValue()
{
return dKey;
}
}