package diffie;
import java.io.*;
import java.math.BigInteger;
class Diffie
{
public static void main(String[]args)throws IOException
{
BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
System.out.println("Enter prime number:");
BigInteger p=new BigInteger(br.readLine());
System.out.print("Enter primitive root of "+p+":");
BigInteger g=new BigInteger(br.readLine());
System.out.println("Enter value for x less than "+p+":");
BigInteger x=new BigInteger(br.readLine());
BigInteger R1=g.modPow(x,p);
System.out.println("R1="+R1);
System.out.print("Enter value for y less than "+p+":");
BigInteger y=new BigInteger(br.readLine());
BigInteger R2=g.modPow(y,p);
System.out.println("R2="+R2);
BigInteger k1=R2.modPow(x,p);
System.out.println("Key calculated at Alice's side:"+k1);
BigInteger k2=R1.modPow(y,p);
System.out.println("Key calculated at Bob's side:"+k2);
System.out.println("deffie hellman secret key Encryption has Taken");
}
}
/* OUTPUT
Enter prime number:
11
Enter primitive root of 11:7
Enter value for x less than 11:
3
R1=2
Enter value for y less than 11:6
R2=4
Key calculated at Alice's side:9
Key calculated at Bob's side:9
deffie hellman secret key Encryption has Taken
*/
how can i generate random values
for the value of p,q and private keys for both client and server?