FeistelTest

package feistel;


import java.util.Arrays;

/**
 *
 *@author generalandroid
 *
 *Feistel密码算法
 * **/
public class FeistelTest {

    /**加密轮数**/
    private static final int LOOP_NUM=16;
    private String [] keys=new String[LOOP_NUM];
    private String [] pContent;
    private String [] cContent;
    private int origin_length;

    public static void main(String[] args){

        FeistelTest feistelTest=new FeistelTest("切切切切切切切切切切切切切切切切切切","ABCDE");
        feistelTest.encrypt();
        feistelTest.decrypt();


    }
    public FeistelTest(String content,String key){
        generateKey(key);
        divideGroups(content);

        System.out.println("原始明文："+content+"\n原始密钥："+key);
    }


    public void encrypt(){
        StringBuilder c=new StringBuilder();
        for(int i=0;i-1;i--){
                content=f(i,content,flag);
            }
        }
        return content;

    }
    /**f函数**/
    public String f(int time,String content,int flag){
        if(content.length()>8){
            System.out.println("ERROR!!!!!");
        }
        String LE=content.substring(0,4);
        String RE=content.substring(4,8);
        String LE1=null;
        String RE1=null;
        String key=keys[time];
//        System.out.println("LE:"+LE+"\t RE:"+RE+"\t key:"+key);
        char[] tmp=new char[4];
        for(int j=0;j<4;j++){
            tmp[j]=(char)(RE.charAt(j)^key.charAt(4*j)^LE.charAt(j));
        }
//        System.out.println("tmp re:"+Arrays.toString(tmp));
        LE1=RE;
        RE1=new String(tmp);
//        System.out.println("time:"+time+"\t L:"+LE1+RE1+"\t key:"+key);


        if (((flag == 0) && (time == 15)) || ((flag == 1) && (time == 0))) {
           return RE1+LE1;
        }

        return LE1+RE1;
    }


}