Des对称加密和解密

des堆成加密

package com.jay.encryption;

import org.apache.tomcat.util.codec.binary.Base64;

import javax.crypto.Cipher;
import javax.crypto.CipherInputStream;
import javax.crypto.CipherOutputStream;
import javax.crypto.KeyGenerator;
import javax.crypto.spec.IvParameterSpec;
import java.io.*;
import java.security.Key;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.security.spec.AlgorithmParameterSpec;


/**
 * @version 0.0.1
 * @program: spring-poi-demo
 * @description: Java DES对称加密工具类
 * @author: huangzq
 * @create: 2020-12-04 14:19
 */
public class DesUtil {

    /**
     * CFB
     */
    public static final String CFB = "CFB";

    /**
     * OFB
     */
    public static final String OFB = "OFB";

    /**
     * CBC
     */
    public static final String CBC = "CBC";

    /**
     * iv向量
     */
    private static final byte[] DESIV = {(byte) 0xCE, (byte) 0x35, (byte) 0x5,
            (byte) 0xD, (byte) 0x98, (byte) 0x91, (byte) 0x8, (byte) 0xA};

    /**
     * AlgorithmParameterSpec
     */
    private static AlgorithmParameterSpec IV = null;

    /**
     * 安全随机使用的实例类型 SHA1PRNG
     */
    private static final String SHA1PRNG = "SHA1PRNG";

    //des的模式字符串内容不要修改，保持下面信息
    /**
     * DES默认模式
     */
    private static final String DES = "DES";

    /**
     * CBC加密模式  这里测试使用的是这个模式
     */
    private static final String DES_CBC_PKCS5PADDING = "DES/CBC/PKCS5Padding";

    /**
     * OFB加密模式
     */
    private static final String DES_OFB_PKCS5PADDING = "DES/OFB/PKCS5Padding";

    /**
     * CFB加密模式
     */
    private static final String DES_CFB_PKCS5_PADDING = "DES/CFB/PKCS5Padding";

    /**
     * 加密模式
     */
    private static final int ENCRYPT_MODE = 1;

    /**
     * 解密模式
     */
    private static final int DECRYPT_MODE = 2;

    /**
     * **
     */
    private Key key;

    public DesUtil(String str) {
        getKey(str);
    }

    public Key getKey() {
        return key;
    }

    public void setKey(Key key) {
        this.key = key;
    }

    /**
     * 通过**获得key
     *
     * @param secretKey **(自己定义的密匙)
     */
    public void getKey(String secretKey) {
        try {
            SecureRandom secureRandom = SecureRandom.getInstance(SHA1PRNG);
            secureRandom.setSeed(secretKey.getBytes());
            KeyGenerator generator = null;
            try {
                generator = KeyGenerator.getInstance(DES);
            } catch (NoSuchAlgorithmException e) {
                e.printStackTrace();
            }
            generator.init(secureRandom);
            IV = new IvParameterSpec(DESIV);
            this.key = generator.generateKey();
            generator = null;
        } catch (Exception e) {
            throw new RuntimeException("Error in getKey(String secretKey), Cause: " + e);
        }
    }

    /**
     * 字符串des加密
     *
     * @param data 需要加密的字符串
     * @param encryptType  加密模式 (ECB/CBC/OFB/CFB)
     * @return
     * @throws Exception
     */
    public String encrypt(String data, String encryptType) throws Exception {
        Cipher cipher = getPattern(encryptType, ENCRYPT_MODE);
        byte[] pasByte = cipher.doFinal(data.getBytes("UTF-8"));
        return Base64.encodeBase64String(pasByte);
    }

    /**
     * 字符串des解密
     *
     * @param data   需要解密的字符串
     * @param decryptType  解密模式 (ECB/CBC/OFB/CFB)
     * @return
     * @throws Exception
     */
    public String decrypt(String data, String decryptType) throws Exception {
        Cipher cipher = getPattern(decryptType, DECRYPT_MODE);
        byte[] pasByte = cipher.doFinal(Base64.decodeBase64(data));
        return new String(pasByte, "UTF-8");
    }

    /**
     * 初始化cipher
     *
     * @param type   加密/解密模式 (ECB/CBC/OFB/CFB)
     * @param cipherMode   cipher工作模式 1：加密； 2：解密
     * @return
     * @throws Exception
     */
    private Cipher getPattern(String type, int cipherMode) throws Exception {
        Cipher cipher;
        switch (type) {
            case CBC:
                cipher = Cipher.getInstance(DES_CBC_PKCS5PADDING);
                cipher.init(cipherMode, key, IV);
                break;
            case OFB:
                cipher = Cipher.getInstance(DES_OFB_PKCS5PADDING);
                cipher.init(cipherMode, key, IV);
                break;
            case CFB:
                cipher = Cipher.getInstance(DES_CFB_PKCS5_PADDING);
                cipher.init(cipherMode, key, IV);
                break;
            default:
                cipher = Cipher.getInstance(DES);
                cipher.init(cipherMode, key);
                break;
        }
        return cipher;
    }

    /**
     * 文件 file 进行加密并保存目标文件 destFile 中
     *
     * @param file   要加密的文件 如 c:/test/file.txt
     * @param destFile   加密后存放的文件名 如 c:/ 加密后文件 .txt
     * @param encryptType  加密模式 (ECB/CBC/OFB/CFB)
     * @return  加密结果   0：异常 1：加密成功； 5：未找到需要加密的文件
     */
    public int encryptFile(String file, String destFile, String encryptType) {
        int result = 0;
        try {
            Cipher cipher = getPattern(encryptType, ENCRYPT_MODE);
            InputStream is = new FileInputStream(file);
            OutputStream out = new FileOutputStream(destFile);
            CipherInputStream cis = new CipherInputStream(is, cipher);
            byte[] buffer = new byte[1024];
            int r;
            while ((r = cis.read(buffer)) > 0) {
                out.write(buffer, 0, r);
            }
            cis.close();
            is.close();
            out.close();
            result = 1;
        } catch (FileNotFoundException e) {
            result = 5;
        } catch (Exception e) {
            e.printStackTrace();
        }
        return result;
    }

    /**
     * 文件 file 进行解密并保存目标文件 destFile 中
     *
     * @param file   要解密的文件 如 c:/test/file.txt
     * @param destFile   解密后存放的文件名 如 c:/ 解密后文件 .txt
     * @param decryptType   解密模式 (ECB/CBC/OFB/CFB)
     * @return  解密结果 0：解密异常；1：解密正常；5：未找到需要解密的文件
     */
    public int decryptFile(String file, String destFile, String decryptType) {
        int result = 0;
        try {
            Cipher cipher = getPattern(decryptType, DECRYPT_MODE);
            InputStream is = new FileInputStream(file);
            OutputStream out = new FileOutputStream(destFile);
            CipherOutputStream cos = new CipherOutputStream(out, cipher);
            byte[] buffer = new byte[1024];
            int r;
            while ((r = is.read(buffer)) >= 0) {
                cos.write(buffer, 0, r);
            }
            cos.close();
            out.close();
            is.close();
            result = 1;
        } catch (FileNotFoundException e) {
            result = 5;
        } catch (Exception e) {
            e.printStackTrace();
        }
        return result;
    }

    public static void main(String[] args) throws Exception {

        String testString = "JCccc-你好，我/是/需/要/加*密*的*字*符*串.";
        System.out.println("加密前内容：" + testString);
        //盐、私匙
        String key = "sdds2343dsadfd%$%%^##@";
        DesUtil desUtil = new DesUtil(key);

        String encryptStr = desUtil.encrypt(testString, "CBC");
        System.out.println("加密后：" + encryptStr);
        String decryptStr = desUtil.decrypt(encryptStr, "CBC");
        System.out.println("解密后：:" + decryptStr);
        //============================================
        testString = "admin";
        System.out.println("加密前内容：" + testString);
        //盐、私匙
        key = "sdds2343dsadfd%$%%^##@";
        desUtil = new DesUtil(key);

        encryptStr = desUtil.encrypt(testString, "CBC");
        System.out.println("加密后：" + encryptStr);
        decryptStr = desUtil.decrypt(encryptStr, "CBC");
        System.out.println("解密后：:" + decryptStr);
    }

}