www.pudn.com > encryption.rar > X9_17KeyGen.java

/*
Christoforos Pirillos @ Villanova University - May 1999
based on code from the book "Java Network Programming" by Hughes
*/

package encryption;

/**Produces random 64-bit values according to ANSI X9.17 specification,
that uses the DES encryption algorithm*/

public class X9_17KeyGen {

protected DES des;
protected long v;

/**We start the generator by providing a key and a seed*/
public X9_17KeyGen (long key, long seed) {

	des = new DES(key);
	v=seed;
}

/**Returns a 64-bit key*/
public long nextKey() {
	long t=des.encrypt(System.currentTimeMillis() );
	long r=des.encrypt(t^v);
	v=des.encrypt(t^r);
	return r;
}


}