hi. i recently implemented S-DES algo. Here is the code for key generation.
import java.math.*;
import java.security.*;
public class keyGenerator {
int bitLength=10;
int certainty=20;
int i=0,j=0,tempInt1,tempInt2;
long l;
byte[] actual10Key=new byte[10];
byte[] permuted10Key=new byte[10];
byte[] permuted10KeyCopy=new byte[10];
byte[] cls10Temp1=new byte[10];
byte[] subKey8Temp=new byte[8];
byte[] subKey1=new byte[8];
byte[] subKey2=new byte[8];
byte tempByte1;
int [] p10={3,5,2,7,4,10,1,9,8,6};
int [] p8={6,3,7,4,8,5,10,9};
BigInteger bigIntKey;
//BigInteger clsBigIntKey;
//BigInteger tempBig1;
public keyGenerator(){
/******************************************/
/*this block generates a random PRIME, converts
it to binary and stores it as an array*/
/*******************************************/
SecureRandom sr=new SecureRandom();
bigIntKey=new BigInteger(bitLength,certainty,sr);
int no=bigIntKey.intValue();
String s=Integer.toBinaryString(no);
char c[]=s.toCharArray();
while(i<10){
tempInt1=c[i];
if(tempInt1==48)
tempInt1-=48;
else if(tempInt1==49)
tempInt1-=48;
actual10Key[i]=(byte) tempInt1;
i++;
}
System.out.println("\n\n\n");
System.out.println("actual key : "+bigIntKey);
System.out.print("actual 10 bit key : ");
for(i=0;i<10;i++){
System.out.print(actual10Key[i]+" ");
}
System.out.println();
System.out.print("permuted 10 bit key : ");
for(i=0;i<10;i++){ //10 bit key permutation
tempInt1=p10[i];
permuted10Key[i]=actual10Key[tempInt1-1];
permuted10KeyCopy[i]=permuted10Key[i];
System.out.print(permuted10Key[i]+" ");
}
System.out.println();
subKeyGenerator();
} //end of constructor
/*********************************************/
/*******used for circular left shift**********/
/*********************************************/
void cls(int noOfCls){
for(i=0;i<10;i++)
cls10Temp1[i]=permuted10Key[i];
for(j=0;j<noOfCls;j++)
{
tempByte1=cls10Temp1[0];
for(i=0;i<9;i++)
cls10Temp1[i]=cls10Temp1[i+1];
cls10Temp1[i]=tempByte1;
}
System.out.print("cls temp1 : ");
for(i=0;i<10;i++){
System.out.print(cls10Temp1[i]+" ");
}
}
/****************************************/
/********creates two sub keys************/
/****************************************/
byte[] subKeyInitiator(int clsNo){
cls(clsNo);
for(i=0;i<8;i++){
tempInt2=p8[i];
subKey8Temp[i]=cls10Temp1[tempInt2-1];
}
return subKey8Temp;
}
void subKeyGenerator(){
subKey1=subKeyInitiator(1);
System.out.println();
System.out.print("subkey 1 : ");
for(i=0;i<8;i++)
System.out.print(subKey1[i]+" ");
System.out.println();
subKey2=subKeyInitiator(3);
System.out.println();
System.out.print("subkey 2 : ");
for(i=0;i<8;i++)
System.out.print(subKey2[i]+" ");
}
public static void main(String args[]) throws java.lang.ArrayIndexOutOfBoundsException{
keyGenerator t=new keyGenerator();
}
}can anyone please suggest some good modifications so as to make the code a bit simpler to implement??? this code has gone way out of hand.