小程序js解密羣組數據

1.下載相關js庫:
http://download.csdn.net/download/laixiao_hero/10126657

2.封裝RdWXBizDataCrypt.js工具類：

/**
 * Created by lx on 2017/11/21.
 */
// 引入CryptoJS
var Crypto = require('cryptojs/cryptojs.js').Crypto;

function RdWXBizDataCrypt(appId, sessionKey) {
  this.appId = appId
  this.sessionKey = sessionKey
}

RdWXBizDataCrypt.prototype.decryptData = function (encryptedData, iv) {
  // base64 decode ：使用 CryptoJS 中 Crypto.util.base64ToBytes()進行 base64解碼
  var encryptedData = Crypto.util.base64ToBytes(encryptedData)
  var key = Crypto.util.base64ToBytes(this.sessionKey);
  var iv = Crypto.util.base64ToBytes(iv);

  // 對稱解密使用的算法爲 AES-128-CBC，數據採用PKCS#7填充
  var mode = new Crypto.mode.CBC(Crypto.pad.pkcs7);

  try {
    // 解密
    var bytes = Crypto.AES.decrypt(encryptedData, key, {
      asBpytes: true,
      iv: iv,
      mode: mode
    });

    var decryptResult = JSON.parse(bytes);

  } catch (err) {
    console.log(err)
    return false;
  }

  if (decryptResult.watermark.appid !== this.appId) {
    console.log(err)
  }

  return decryptResult
}

module.exports = RdWXBizDataCrypt

3.直接調用

var WXBizDataCrypt = require('RdWXBizDataCrypt.js');

//核心代碼
var pc = new WXBizDataCrypt(appid, session_key);
var data = pc.decryptData(encryptedData, iv);