构建ASP.NET MVC5+EF6+EasyUI 1.4.3+Unity4.x注入的后台管理系统（62）-EF链接串加密

前言：

　　这一节提供一个简单的功能，这个功能看似简单，找了一下没找到EF链接数据库串的加密帮助文档，只能自己写了，这样也更加符合自己的加密要求

有时候我们发布程序为了避免程序外的SQL链接串明文暴露，需要进行一些加密手段！
加密主要分几类：对称加密，非对称加密，散列算法（自己百度脑补，这里不再多说）
我这里选择AES 256位的加密，主要加密速度算法快，安全性高，资源消耗低。
公司一直在使用AES加密来加密一些小数据量的数据，比较方法和安全

　　这是我选择加密AES的理由,当然你可以选择其他有名的加密算法,比如MD5,SHA,3DES.(注：大公司应该都是禁止自行写算法的来加解密的)

知识点：

　数据的使用跟我们登录流程基本都是一样的，获取加密链接串，然后解密使用

　所以我们需要：

加密类
加密工具
EF在何处使用链接字符串

1.加密类

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Security.Cryptography;
using System.IO;
namespace Apps.Common
{
    public class AESEncryptHelper
    {

        /// <summary>
        /// 获取密钥
        /// </summary>
        private static string Key
        {
            get { return @")O[NB]6,YF}+efcaj{+oESb9d8>Z'e9M"; }
        }

        /// <summary>
        /// 获取向量
        /// </summary>
        private static string IV
        {
            get { return @"L+\~f4,Ir)b$=pkf"; }
        }

        #region 参数是byte[]类型
        /// <summary>
        /// AES加密
        /// </summary>
        /// <param name="Data">被加密的明文</param>
        /// <param name="Key">密钥</param>
        /// <param name="Vector">向量</param>
        /// <returns>密文</returns>
        public static Byte[] AESEncrypt(Byte[] Data, String Key, String Vector)
        {
            Byte[] bKey = new Byte[32];
            Array.Copy(Encoding.UTF8.GetBytes(Key.PadRight(bKey.Length)), bKey, bKey.Length);
            Byte[] bVector = new Byte[16];
            Array.Copy(Encoding.UTF8.GetBytes(Vector.PadRight(bVector.Length)), bVector, bVector.Length);
            Byte[] Cryptograph = null; // 加密后的密文
            Rijndael Aes = Rijndael.Create();
            try
            {
                // 开辟一块内存流
                using (MemoryStream Memory = new MemoryStream())
                {
                    // 把内存流对象包装成加密流对象
                    using (CryptoStream Encryptor = new CryptoStream(Memory,
                     Aes.CreateEncryptor(bKey, bVector),
                     CryptoStreamMode.Write))
                    {
                        // 明文数据写入加密流
                        Encryptor.Write(Data, 0, Data.Length);
                        Encryptor.FlushFinalBlock();

                        Cryptograph = Memory.ToArray();
                    }
                }
            }
            catch
            {
                Cryptograph = null;
            }
            return Cryptograph;
        }

        /// <summary>
        /// AES解密
        /// </summary>
        /// <param name="Data">被解密的密文</param>
        /// <param name="Key">密钥</param>
        /// <param name="Vector">向量</param>
        /// <returns>明文</returns>
        public static Byte[] AESDecrypt(Byte[] Data, String Key, String Vector)
        {
            Byte[] bKey = new Byte[32];
            Array.Copy(Encoding.UTF8.GetBytes(Key.PadRight(bKey.Length)), bKey, bKey.Length);
            Byte[] bVector = new Byte[16];
            Array.Copy(Encoding.UTF8.GetBytes(Vector.PadRight(bVector.Length)), bVector, bVector.Length);

            Byte[] original = null; // 解密后的明文

            Rijndael Aes = Rijndael.Create();
            try
            {
                // 开辟一块内存流，存储密文
                using (MemoryStream Memory = new MemoryStream(Data))
                {
                    // 把内存流对象包装成加密流对象
                    using (CryptoStream Decryptor = new CryptoStream(Memory,
                    Aes.CreateDecryptor(bKey, bVector),
                    CryptoStreamMode.Read))
                    {
                        // 明文存储区
                        using (MemoryStream originalMemory = new MemoryStream())
                        {
                            Byte[] Buffer = new Byte[1024];
                            Int32 readBytes = 0;
                            while ((readBytes = Decryptor.Read(Buffer, 0, Buffer.Length)) > 0)
                            {
                                originalMemory.Write(Buffer, 0, readBytes);
                            }

                            original = originalMemory.ToArray();
                        }
                    }
                }
            }
            catch
            {
                original = null;
            }
            return original;
        }

        #endregion

        #region 参数是string类型

      

        /// <summary>
        /// AES加密
        /// </summary>
        /// <param name="plainStr">明文字符串</param>
        /// <returns>密文</returns>
        public static string AESEncrypt(string plainStr)
        {
            byte[] bKey = Encoding.UTF8.GetBytes(Key);
            byte[] bIV = Encoding.UTF8.GetBytes(IV);
            byte[] byteArray = Encoding.UTF8.GetBytes(plainStr);

            string encrypt = null;
            Rijndael aes = Rijndael.Create();
            using (MemoryStream mStream = new MemoryStream())
            {
                using (CryptoStream cStream = new CryptoStream(mStream, aes.CreateEncryptor(bKey, bIV), CryptoStreamMode.Write))
                {
                    cStream.Write(byteArray, 0, byteArray.Length);
                    cStream.FlushFinalBlock();
                    encrypt = Convert.ToBase64String(mStream.ToArray());
                }
            }
            aes.Clear();
            return encrypt;
        }

        /// <summary>
        /// AES加密
        /// </summary>
        /// <param name="plainStr">明文字符串</param>
        /// <param name="returnNull">加密失败时是否返回 null，false 返回 String.Empty</param>
        /// <returns>密文</returns>
        public static string AESEncrypt(string plainStr, bool returnNull)
        {
            string encrypt = AESEncrypt(plainStr);
            return returnNull ? encrypt : (encrypt == null ? String.Empty : encrypt);
        }

        /// <summary>
        /// AES解密
        /// </summary>
        /// <param name="encryptStr">密文字符串</param>
        /// <returns>明文</returns>
        public static string AESDecrypt(string encryptStr)
        {
            byte[] bKey = Encoding.UTF8.GetBytes(Key);
            byte[] bIV = Encoding.UTF8.GetBytes(IV);
            byte[] byteArray = Convert.FromBase64String(encryptStr);

            string decrypt = null;
            Rijndael aes = Rijndael.Create();
            using (MemoryStream mStream = new MemoryStream())
            {
                using (CryptoStream cStream = new CryptoStream(mStream, aes.CreateDecryptor(bKey, bIV), CryptoStreamMode.Write))
                {
                    cStream.Write(byteArray, 0, byteArray.Length);
                    cStream.FlushFinalBlock();
                    decrypt = Encoding.UTF8.GetString(mStream.ToArray());
                }
            }
            aes.Clear();
            return decrypt;
        }

        /// <summary>
        /// AES解密
        /// </summary>
        /// <param name="encryptStr">密文字符串</param>
        /// <param name="returnNull">解密失败时是否返回 null，false 返回 String.Empty</param>
        /// <returns>明文</returns>
        public static string AESDecrypt(string encryptStr, bool returnNull)
        {
            string decrypt = AESDecrypt(encryptStr);
            return returnNull ? decrypt : (decrypt == null ? String.Empty : decrypt);
        }


        #endregion

        #region 256位AES加密算法

        /// <summary>
        /// 256位AES加密
        /// </summary>
        /// <param name="toEncrypt"></param>
        /// <returns></returns>
        public static string Encrypt(string toEncrypt)
        {
            // 256-AES key    
            byte[] keyArray = UTF8Encoding.UTF8.GetBytes(Key);
            byte[] toEncryptArray = UTF8Encoding.UTF8.GetBytes(toEncrypt);

            RijndaelManaged rDel = new RijndaelManaged();
            rDel.Key = keyArray;
            rDel.Mode = CipherMode.ECB;
            rDel.Padding = PaddingMode.PKCS7;

            ICryptoTransform cTransform = rDel.CreateEncryptor();
            byte[] resultArray = cTransform.TransformFinalBlock(toEncryptArray, 0, toEncryptArray.Length);

            return Convert.ToBase64String(resultArray, 0, resultArray.Length);
        }

        /// <summary>
        /// 256位AES解密
        /// </summary>
        /// <param name="toDecrypt"></param>
        /// <returns></returns>
        public static string Decrypt(string toDecrypt)
        {
            // 256-AES key    
            byte[] keyArray = UTF8Encoding.UTF8.GetBytes(Key);
            byte[] toEncryptArray = Convert.FromBase64String(toDecrypt);

            RijndaelManaged rDel = new RijndaelManaged();
            rDel.Key = keyArray;
            rDel.Mode = CipherMode.ECB;
            rDel.Padding = PaddingMode.PKCS7;

            ICryptoTransform cTransform = rDel.CreateDecryptor();
            byte[] resultArray = cTransform.TransformFinalBlock(toEncryptArray, 0, toEncryptArray.Length);

            return UTF8Encoding.UTF8.GetString(resultArray);
        }

        #endregion
    }
}

AESEncryptHelper.cs

网上一抓一大把，自己搜索想要的加密类啦！

2.加密工具

加密工具这个网上抓不到，需要自己结合加密类来开发，这个不用我带领大伙来开发吧，好吧

新建一个WinFrom程序，命名Apps.EncryptHelper,引用你加密类的所在的类库，或者直接放到Apps.EncryptHelper下就可以

从工具栏拉取2个TextBox和2个Button排版好，基本页面就做完了，最后分别双击两个按钮进入事件实现代码

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using Apps.Common;
namespace Apps.EncryptHelper
{
    public partial class Encrypt : Form
    {
        public Encrypt()
        {
            InitializeComponent();
        }
        //加密
        private void btnEncrypt_Click(object sender, EventArgs e)
        {
            if (string.IsNullOrEmpty(txtSourceText.Text))
            {
                MessageBox.Show("没数据加毛密-_-!");
                return;
            }
            else
            {
               txtResultText.Text = AESEncryptHelper.Encrypt(txtSourceText.Text);
            }
        }
        //解密
        private void btnDecrypt_Click(object sender, EventArgs e)
        {
            if (string.IsNullOrEmpty(txtSourceText.Text))
            {
                MessageBox.Show("没数据解毛密-_-!");
                return;
            }
            else if (!IsBase64Formatted(txtSourceText.Text))
            {
                MessageBox.Show("别逗了,我只认识被我加过密的？");
                return;
            }
            else
            {
                txtResultText.Text = AESEncryptHelper.Decrypt(txtSourceText.Text);
            }
        }

        public static bool IsBase64Formatted(string input)
        {
            try
            {
                Convert.FromBase64String(input);
                return true;
            }
            catch
            {
                return false;
            }
        }
    }
}

几十行代码，解决车房老婆问题！运行....

3.结合进EF

这块还是比较容易搞定的

第一：找到web.config的connectionStrings的EF链接串

第二：把修改对应Key串的Value

 <connectionStrings>
    <add name="DBContainer" connectionString="ka7ocMA8nEYPjbQYUlVwbsmTeIdxKGE+ZfXAu3/0eMhVRP+iN+9ECpY/lItoY9vfZVDA9EVgmMzH/8Z0rxRIhGPRhVMFWliBuJ9RDGtHbqRY02voyLbrZ7IiXRnXyhlLFsvgj23KXnHl8J6jxB1QNsmuUxPlqnD6HP9y5RQq2EJ//OT+uKqhVC1qUqVzdY+XR6HX/O5jGk6kJGk3Nk83qo09eBOundO7OdxQG9SXPUYNyZjhyx9YV2/1UbghuxHrxHrAuxiE4mJLqH/rusjAy8d3LS/ROiiBszSY+I400Ce4NigDwZaG679yvBKBQ5pg" providerName="System.Data.EntityClient" />
  </connectionStrings>

第三：找到EF读取串的地方

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Apps.Common
{
    public class ConfigPara
    {
        public static string EFDBConnection {
            get {
                string connection = System.Configuration.ConfigurationManager.ConnectionStrings["DBContainer"].ConnectionString;
                return AESEncryptHelper.Decrypt(connection);
            }
        }
    }
}