Binaryworld - RC4 Implementation in java ... [ JAVA -> security ]

This code will help you to use RC4 in java. you dont require javax.sec.. blah blah.. Just compile and run
Remember the crypt routine here changes the argument input. You can easily use this code for file encrytpion also.
For file encr./decr. just open file and get the input/output stream, then fetch the buffer, use this buffer to create string object and then supply this object to string buffer constructor to manipulate.. after invokation of the same use result to write data in other file.. thats all..

This is reference implementation only, Please read security policies published by US goverment, auther or the site admins has no relation with the violation if happens due to copying the source from this site.

Click here to copy the following block

public class arcMain {

public arcMain() {
}

public static void main(String[] args) {
  StringBuffer input,key,result;
  input = new StringBuffer("TEXT");
  key=new StringBuffer("keyText");
  result=new StringBuffer();
  byte[] buf;
   int len;
//first encrypt the input with the key and print
  Crypt(input,key);
  System.out.println("DATA : "+input);
//lets decrypt it
  Crypt(input,key);
  System.out.println("DATA : "+input);
}
static void Crypt(StringBuffer inp,StringBuffer key)
{
  int Sbox[];
  int Sbox2[];
  Sbox=new int[257];
  Sbox2=new int[257];
  int i, j, t, x;

  String OurUnSecuredKey = "CrusadersNeverSleep";
  char temp , k;
  i = 0;
  j = 0;
  k = 0;
  t = 0;
  x = 0;
  temp = 0;

  //initialize sbox i
  for( i = 0; i < 256; i++)
  {
    Sbox[i] = i;
  }

  j = 0;
  if(key.length() >0)
  {
    for(i = 0; i < 256 ; i++)
    {
      if(j == key.length() )
        j = 0;

      Sbox2[i] = key.charAt(j++);
    }
  }
  else
  {
    for(i = 0; i < 256 ; i++)
    {
      if(j == OurUnSecuredKey.length() +1)
        j = 0;

      Sbox2[i] = OurUnSecuredKey.charAt(j++);
    }
  }

  j = 0 ;
  for(i = 0; i < 256; i++)
  {
    j = (j + Sbox[i] + Sbox2[i]) % 256;
    temp = (char)Sbox[i];
    Sbox[i] = Sbox[j];
    Sbox[j] = temp;
  }

  i = j = 0;
  for(x = 0; x < inp.length() ; x++)
  {
    //increment i
    i = (i + 1) % 256;
    //increment j
    j = (j + Sbox[i]) % 256;

    //Scramble SBox #1 further so encryption routine will
    //will repeat itself at great interval
    temp = (char)Sbox[i];
    Sbox[i] = Sbox[j] ;
    Sbox[j] = temp;

    //Get ready to create pseudo random byte for encryption key
    t = ( Sbox[i] + Sbox[j]) % 256 ;

    //get the random byte
    k = (char)Sbox[t];

    //xor with the data and done
    inp.setCharAt(x, (char)(inp.charAt(x) ^ k));
  }
}

}