decrypt.java

S-DES的编程实现 S-DES的加密使用8位明文和10位密钥做为输入

// SDES Decrypt
//
// R. Perry, Jan. 2002

public class Decrypt
{
  public static void main( String args[]) throws Exception
  {
    if( args.length != 2) {
      System.err.println( "Usage: Decrypt key plaintext");
      System.exit(1);
    }

   // first command-line argument is 10-bit key in binary
   //
    int K = Integer.parseInt( args[0], 2);

   // create an instance of the SDES Algorithm
   //
    SDES A = new SDES( K);

   // second command-line argument is 8-bit plaintext in binary
   //
    int m = Integer.parseInt( args[1], 2);

   // decrypt
   //
    m = A.decrypt( m);

   // display in binary
   //
    SDES.printb( m, 8);
    System.out.println();
  }
}

/*

sample run:

% java Encrypt 0000011111 11111111
11100001
% java Decrypt 0000011111 11100001
11111111
%

*/