JS前端加密JAVA后端解密详解

最近有一个加解密的需求，其实没有什么难度，但是实践过程中踩了很多坑，把踩坑过程分享出来。

1、前端JS加密

/**
         * 加密（需要先加载aes.min.js文件）
         * @param word
         * @returns {*}
         */
        function aesMinEncrypt(word){
            var _word = CryptoJS.enc.Utf8.parse(word),
                _key = CryptoJS.enc.Utf8.parse("ihaierForTodoKey"),
                _iv = CryptoJS.enc.Utf8.parse("ihaierForTodo_Iv");
            var encrypted = CryptoJS.AES.encrypt(_word, _key, {
                        iv: _iv,
                        mode: CryptoJS.mode.CBC,
                        padding: CryptoJS.pad.Pkcs7
                });
            return encrypted.toString();
        }

/**
 * 解密（需要先加载aes.min.js文件）
 * @param word
 * @returns {*}
 */
function aesDecrypt(word) {
    var _key = CryptoJS.enc.Utf8.parse("ihaierForTodoKey"),
        _iv = CryptoJS.enc.Utf8.parse("ihaierForTodo_Iv");
    var decrypted = CryptoJS.AES.decrypt(word, _key, {
                iv: _iv,
                mode: CryptoJS.mode.CBC,
                padding: CryptoJS.pad.Pkcs7
        });
    return decrypted.toString(CryptoJS.enc.Utf8);
}

key：十六位作为密钥（前后端必须一致）
iv：十六位作为密钥偏移量（前后端必须一致）
算法：AES/CBC/PKCS7Padding
注意点：JAVA本身不支持PKCS7，只支持PKCS5，但是通过实验，两者即使不一样，也可以进行解密

2、后端JAVA解密

需要导入的jar包（版本没要求）：

org.apache.commons.codec.jar

org.apache.commons.lang.jar

package com.founder.mrp.util;

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

import org.apache.commons.codec.binary.Base64;
import org.apache.commons.lang.StringUtils;

public class AesUtil {
    
    //密钥 (需要前端和后端保持一致)十六位作为密钥
    private static final String KEY = "ihaierForTodoKey";

    //密钥偏移量 (需要前端和后端保持一致)十六位作为密钥偏移量
    private static final String IV = "ihaierForTodo_Iv";
    
    //算法
    private static final String ALGORITHMSTR = "AES/CBC/PKCS5Padding";
    
    //SSO的TOKEN
    private static final String token = "4AaWABnPB5/1Z2EIEXwSfigudpiM4kzLkmIrKQPmS9w=";
    /** 
     * base 64 decode 
     * @param base64Code 待解码的base 64 code 
     * @return 解码后的byte[] 
     * @throws Exception 
     */
    public static byte[] base64Decode(String base64Code) throws Exception{
        /**sun.misc.BASE64Decoder是java内部类，有时候会报错，
         * 用org.apache.commons.codec.binary.Base64替代，效果一样。
         */
        //Base64 base64 = new Base64();
        //byte[] bytes = base64.decodeBase64(new String(base64Code).getBytes());
        //new BASE64Decoder().decodeBuffer(base64Code);
        return StringUtils.isEmpty(base64Code) ? null : new Base64().decodeBase64(new String(base64Code).getBytes());
    }
    
    /** 
     * AES解密 
     * @param encryptBytes 待解密的byte[] 
     * @return 解密后的String 
     * @throws Exception 
     */  
    public static String aesDecryptByBytes(byte[] encryptBytes) throws Exception {

        Cipher cipher = Cipher.getInstance(ALGORITHMSTR);
        
        byte[] temp = IV.getBytes("UTF-8");
        IvParameterSpec iv = new IvParameterSpec(temp);
        
        cipher.init(Cipher.DECRYPT_MODE, new SecretKeySpec(KEY.getBytes(), "AES"), iv);
        byte[] decryptBytes = cipher.doFinal(encryptBytes);
        
        System.out.print(new String(decryptBytes));
        return new String(decryptBytes);
    }

    /** 
     * 将base 64 code AES解密 
     * @param encryptStr 待解密的base 64 code
     * @return 解密后的string
     * @throws Exception
     */ 
    public static String aesDecrypt(String encryptStr) throws Exception {  
        return StringUtils.isEmpty(encryptStr) ? null : aesDecryptByBytes(base64Decode(encryptStr));  
    }

    public static void main(String[] args) throws Exception {
        aesDecrypt(token);
    }
}

密钥和密钥便宜量必须和前端一致
算法可以采用PKCS5（JAVA本身不支持PKCS7），如果想使用PKCS7，需要额外引入jar包。

附录：aes.min.js压缩文件

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!function(e,r,i){"object"==typeof exports?module.exports=exports=r(require("./core.min"),require("./enc-base64.min"),require("./md5.min"),require("./evpkdf.min"),require("./cipher-core.min")):"function"==typeof define&&define.amd?define(["./core.min","./enc-base64.min","./md5.min","./evpkdf.min","./cipher-core.min"],r):r(e.CryptoJS)}(this,function(e){return function(){var r=e,i=r.lib,n=i.BlockCipher,o=r.algo,t=[],c=[],s=[],f=[],a=[],d=[],u=[],v=[],h=[],y=[];!function(){for(var e=[],r=0;r<256;r++)r<128?e[r]=r<<1:e[r]=r<<1^283;for(var i=0,n=0,r=0;r<256;r++){var o=n^n<<1^n<<2^n<<3^n<<4;o=o>>>8^255&o^99,t[i]=o,c[o]=i;var p=e[i],l=e[p],_=e[l],k=257*e[o]^16843008*o;s[i]=k<<24|k>>>8,f[i]=k<<16|k>>>16,a[i]=k<<8|k>>>24,d[i]=k;var k=16843009*_^65537*l^257*p^16843008*i;u[o]=k<<24|k>>>8,v[o]=k<<16|k>>>16,h[o]=k<<8|k>>>24,y[o]=k,i?(i=p^e[e[e[_^p]]],n^=e[e[n]]):i=n=1}}();var p=[0,1,2,4,8,16,32,64,128,27,54],l=o.AES=n.extend({_doReset:function(){if(!this._nRounds||this._keyPriorReset!==this._key){for(var e=this._keyPriorReset=this._key,r=e.words,i=e.sigBytes/4,n=this._nRounds=i+6,o=4*(n+1),c=this._keySchedule=[],s=0;s<o;s++)if(s<i)c[s]=r[s];else{var f=c[s-1];s%i?i>6&&s%i==4&&(f=t[f>>>24]<<24|t[f>>>16&255]<<16|t[f>>>8&255]<<8|t[255&f]):(f=f<<8|f>>>24,f=t[f>>>24]<<24|t[f>>>16&255]<<16|t[f>>>8&255]<<8|t[255&f],f^=p[s/i|0]<<24),c[s]=c[s-i]^f}for(var a=this._invKeySchedule=[],d=0;d<o;d++){var s=o-d;if(d%4)var f=c[s];else var f=c[s-4];d<4||s<=4?a[d]=f:a[d]=u[t[f>>>24]]^v[t[f>>>16&255]]^h[t[f>>>8&255]]^y[t[255&f]]}}},encryptBlock:function(e,r){this._doCryptBlock(e,r,this._keySchedule,s,f,a,d,t)},decryptBlock:function(e,r){var i=e[r+1];e[r+1]=e[r+3],e[r+3]=i,this._doCryptBlock(e,r,this._invKeySchedule,u,v,h,y,c);var i=e[r+1];e[r+1]=e[r+3],e[r+3]=i},_doCryptBlock:function(e,r,i,n,o,t,c,s){for(var f=this._nRounds,a=e[r]^i[0],d=e[r+1]^i[1],u=e[r+2]^i[2],v=e[r+3]^i[3],h=4,y=1;y<f;y++){var p=n[a>>>24]^o[d>>>16&255]^t[u>>>8&255]^c[255&v]^i[h++],l=n[d>>>24]^o[u>>>16&255]^t[v>>>8&255]^c[255&a]^i[h++],_=n[u>>>24]^o[v>>>16&255]^t[a>>>8&255]^c[255&d]^i[h++],k=n[v>>>24]^o[a>>>16&255]^t[d>>>8&255]^c[255&u]^i[h++];a=p,d=l,u=_,v=k}var p=(s[a>>>24]<<24|s[d>>>16&255]<<16|s[u>>>8&255]<<8|s[255&v])^i[h++],l=(s[d>>>24]<<24|s[u>>>16&255]<<16|s[v>>>8&255]<<8|s[255&a])^i[h++],_=(s[u>>>24]<<24|s[v>>>16&255]<<16|s[a>>>8&255]<<8|s[255&d])^i[h++],k=(s[v>>>24]<<24|s[a>>>16&255]<<16|s[d>>>8&255]<<8|s[255&u])^i[h++];e[r]=p,e[r+1]=l,e[r+2]=_,e[r+3]=k},keySize:8});r.AES=n._createHelper(l)}(),e.AES});
//# sourceMappingURL=aes.min.js.map
!function(e,n){"object"==typeof exports?module.exports=exports=n(require("./core.min")):"function"==typeof define&&define.amd?define(["./core.min"],n):n(e.CryptoJS)}(this,function(e){return e.enc.Utf8});
//# sourceMappingURL=enc-utf8.min.js.map

package com.founder.mrp.util;

import org.apache.commons.codec.binary.Base64;
import org.apache.commons.lang.StringUtils;
import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.nio.charset.StandardCharsets;

/**
 * aes加密解密工具类
 * @author hanwl
 *  
 */

public class AesUtil {
    
    //密钥 (需要前端和后端保持一致)十六位作为密钥
    private static final String KEY = "{g;,9~lde^[w`SR5";

    //密钥偏移量 (需要前端和后端保持一致)十六位作为密钥偏移量
    private static final String IV = "$JL<&*lZFsZ?:p#1";
    
    /**
     * base 64 decode 
     * @param base64Code 待解码的base 64 code 
     * @return 解码后的byte[]
     */
    public static byte[] base64Decode(String base64Code) {
        /* sun.misc.BASE64Decoder是java内部类，有时候会报错，
         * 用org.apache.commons.codec.binary.Base64替代，效果一样。
         */
        //Base64 base64 = new Base64();
        //byte[] bytes = base64.decodeBase64(new String(base64Code).getBytes());
        //new BASE64Decoder().decodeBuffer(base64Code);
        return StringUtils.isEmpty(base64Code) ? null : Base64.decodeBase64(base64Code.getBytes());
    }
    
    /** 
     * AES解密 
     * @param encryptBytes 待解密的byte[] 
     * @return 解密后的String 
     * @throws Exception 
     */  
    public static String aesDecryptByBytes(byte[] encryptBytes) throws Exception {
        Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
        
        byte[] temp = IV.getBytes(StandardCharsets.US_ASCII);
        IvParameterSpec iv = new IvParameterSpec(temp);
        
        cipher.init(Cipher.DECRYPT_MODE, new SecretKeySpec(KEY.getBytes(StandardCharsets.US_ASCII), "AES"), iv);
        byte[] decryptBytes = cipher.doFinal(encryptBytes);
        
        return new String(decryptBytes);
    }

    /** 
     * 将base 64 code AES解密 
     * @param encryptStr 待解密的base 64 code
     * @return 解密后的string
     * @throws Exception
     */ 
    public static String aesDecrypt(String encryptStr) throws Exception {  
        return StringUtils.isEmpty(encryptStr) ? null : aesDecryptByBytes(base64Decode(encryptStr));  
    }
    
    @SuppressWarnings("unused")
    public static String aesEncrypt(String str) {
        try {
            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
            IvParameterSpec iv = new IvParameterSpec(IV.getBytes(StandardCharsets.US_ASCII));
            cipher.init(Cipher.ENCRYPT_MODE, new SecretKeySpec(KEY.getBytes(StandardCharsets.US_ASCII), "AES"), iv);
            byte[] encryptBytes = cipher.doFinal(str.getBytes(StandardCharsets.UTF_8));

            return new String(Base64.encodeBase64(encryptBytes),StandardCharsets.US_ASCII);
            //return java.util.Base64.getEncoder().encodeToString(encryptBytes);
        }
        catch (Exception e) {
            e.printStackTrace();
            return "";
        }
    }
        
    /** 
     * 生成一个可选长度的随机数列
     * @param 
     */
    public static String getRandomCode(int length){
        String[] arr = new String[]{"0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "A", "B", "C", "D", "E", "F", "G", 
                                    "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", 
                                    "Y", "Z", "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", 
                                    "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z"};
        String str="";
        for (int i = 0; i < length; i++) {
             int r = (int) (Math.random()*61);
             str += arr[r];
          }
        return str;
    }
    
    public static void main(String[] args) {
        String a1=aesEncrypt("12345asdfg");
        System.out.println(a1);
        try {
            String a2 =aesDecrypt(a1);
            System.out.println(a2);
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        
    }

}