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JAVA SE平台作加密程序

www.MyException.Cn  网友分享于:2013-12-26  浏览:37次
JAVA SE平台做加密程序
要求1.包含程序启动口令
  2.须得与所加密文件放在一个文件夹里
  3.口令本身加密

  4.可以给该文件加密,且具有初始密码,可以修改和删除该密码

  5.最好有图形输入界面。

  我才初学这个,导师就随便布置下来了,一个星期下来,我看的很是茫然,看高手能不能给点建议或是流程图什么的,源程序肯定最好了,嘿嘿
  感谢各位大侠帮忙啊!!


------解决方案--------------------
加密口令用非对称加密算法:比如RSA算法。如果你对它不了解 google之
公式很简单,j自己写一个都容易的很,java有一个BingInteger类,配合数学公式就可以独自写出加密解密程序了


加密大数据的东西(比如文件) 采用对称加密算法 比如DES
这个加密解密解密过程就复杂多了,但是有现成的类呀,你学会调用就可以了

下面给一个例子,你吧文件以字节数组读取出来再进行加密就可以了。当然也可以字符串形式读取出来:
无论怎么读写,都要注意边界

Java code




import java.security.Key;
import java.util.Arrays;

import javax.crypto.Cipher;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESedeKeySpec;
import javax.crypto.spec.IvParameterSpec;

import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;
//http://topic.csdn.net/u/20101112/11/906A2C5D-5F3B-4284-9DE8-DDB3A18B0BA0.html
public class Des {
     
    public static void main(String[] args) throws Exception {
    byte[] key=new BASE64Decoder().decodeBuffer("YWJjZGVmZ2hpamtsbW5vcHFyc3R1dnd4");
        
         byte[] keyiv = { 1, 2, 3, 4, 5, 6, 7, 8 };

        byte[] data="中国ABCabc123".getBytes("UTF-8");
        
        System.out.println("ECB加密解密");
        byte[] str3 = des3EncodeECB(key,data );
        byte[] str4 = ees3DecodeECB(key, str3);
        System.out.println(new BASE64Encoder().encode(str3));
        System.out.println(new String(str4, "UTF-8"));

        System.out.println();

        System.out.println("CBC加密解密");
        byte[] str5 = des3EncodeCBC(key, keyiv, data);
        byte[] str6 = des3DecodeCBC(key, keyiv, str5);
        System.out.println(new BASE64Encoder().encode(str5));
        System.out.println(new String(str6, "UTF-8"));

    }

    /**
     * ECB加密,不要IV
     * @param key 密钥
     * @param data 明文
     * @return Base64编码的密文
     * @throws Exception
     */
    public static byte[] des3EncodeECB(byte[] key, byte[] data)
            throws Exception {

        Key deskey = null;
        DESedeKeySpec spec = new DESedeKeySpec(key);
        SecretKeyFactory keyfactory = SecretKeyFactory.getInstance("desede");
        deskey = keyfactory.generateSecret(spec);

        Cipher cipher = Cipher.getInstance("desede" + "/ECB/PKCS5Padding");

        cipher.init(Cipher.ENCRYPT_MODE, deskey);
        byte[] bOut = cipher.doFinal(data);

        return bOut;
    }

    /**
     * ECB解密,不要IV
     * @param key 密钥
     * @param data Base64编码的密文
     * @return 明文
     * @throws Exception
     */
    public static byte[] ees3DecodeECB(byte[] key, byte[] data)
            throws Exception {

        Key deskey = null;
        DESedeKeySpec spec = new DESedeKeySpec(key);
        SecretKeyFactory keyfactory = SecretKeyFactory.getInstance("desede");
        deskey = keyfactory.generateSecret(spec);

        Cipher cipher = Cipher.getInstance("desede" + "/ECB/PKCS5Padding");

        cipher.init(Cipher.DECRYPT_MODE, deskey);

        byte[] bOut = cipher.doFinal(data);

        return bOut;

    }

    /**
     * CBC加密
     * @param key 密钥
     * @param keyiv IV
     * @param data 明文
     * @return Base64编码的密文
     * @throws Exception
     */
    public static byte[] des3EncodeCBC(byte[] key, byte[] keyiv, byte[] data)
            throws Exception {

        Key deskey = null;
        DESedeKeySpec spec = new DESedeKeySpec(key);
        SecretKeyFactory keyfactory = SecretKeyFactory.getInstance("desede");
        deskey = keyfactory.generateSecret(spec);

        Cipher cipher = Cipher.getInstance("desede" + "/CBC/PKCS5Padding");
        IvParameterSpec ips = new IvParameterSpec(keyiv);
        cipher.init(Cipher.ENCRYPT_MODE, deskey, ips);
        byte[] bOut = cipher.doFinal(data);

        return bOut;
    }

    /**
     * CBC解密
     * @param key 密钥
     * @param keyiv IV
     * @param data Base64编码的密文
     * @return 明文
     * @throws Exception
     */
    public static byte[] des3DecodeCBC(byte[] key, byte[] keyiv, byte[] data)
            throws Exception {

        Key deskey = null;
        DESedeKeySpec spec = new DESedeKeySpec(key);
        SecretKeyFactory keyfactory = SecretKeyFactory.getInstance("desede");
        deskey = keyfactory.generateSecret(spec);

        Cipher cipher = Cipher.getInstance("desede" + "/CBC/PKCS5Padding");
        IvParameterSpec ips = new IvParameterSpec(keyiv);

        cipher.init(Cipher.DECRYPT_MODE, deskey, ips);

        byte[] bOut = cipher.doFinal(data);

        return bOut;

    }

}

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