Aes加密/解密示例项目

#AesEncrypt：Aes加密/解密示例项目 <br>
　　附件中的“AesEncrypt.zip”是本项目的exe文件，可直接下载下来运行和查看。
　　*高级加密标准（英语：Advanced Encryption Standard，缩写：AES），在密码学中又称Rijndael加密法，是美国联邦政府采用的一种区块加密标准。这个标准用来替代原先的DES，已经被多方分析且广为全世界所使用。经过五年的甄选流程，高级加密标准由美国国家标准与技术研究院（NIST）于2001年11月26日发布于FIPS PUB 197，并在2002年5月26日成为有效的标准。2006年，高级加密标准已然成为对称密钥加密中最流行的算法之一。*<br>
　　好的百科已普及，现在来看看这Aes怎么使用，由于需要把加密后的byte[]输出成字符串，但是普通字符串无法兼容，所以这里使用的base64字符串。详见代码AesEncryptAesEncrypt.cs。<br>
　　为了直观的看到Aes的加解密过程，现在给出几个示例，如下图<br>
　　1.在“未加密”的文本框中输入一个普通的字符串，点击“加密”按钮，将在”已加密“的文本框中得到一个Aes加密后的base64字符串。**这个“已加密”的base64字符串就可以放到系统中使用了，例如可以填到数据库链接字符串，也可以存储得到数据中。**<br>
　　2.第一步完成后，“已加密”文本框中已经被填写了Aes加密后的base64字符串，为了看到效果，可以把“未加密”文本框中的普通文本删掉，然后点击“解密”按钮，就可以在“未加密”文本框中看到之前的普通文本。<br>
　　3.经过以上两步操作，我想这个窗体已经完成了示例的作用，Aes加密需要两个byte[]，一个是IV,它是对称算法的初始化向量，一个是Key，它是对称算法的密钥。IV是一个Length=16的byte[]，Key是一个Length=32的byte[]，**因此可以在AesEncryptAesEncrypt.cs类中设置自己的固定密钥用以在程序中加密/解密，如以下代码中所示，可以填写任意的数字，来当做密钥。**<br>
```C#
/// <summary>
/// 对称算法的密钥
/// </summary>
private readonly static byte[] aesKey = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32 };
/// <summary>
/// 对称算法的初始化向量
/// </summary>
private readonly static byte[] aesIV = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 };
```

　　以上步骤是在程序中的基本使用方式，Aes还可以有更多的用途，以下来个抛砖引玉。<br>
　　1.在“玩玩解密”窗体中点击“发送”按钮之后，将把“未加密”中的文本使用Aes加密后转换成base64字符串填写到“已加密”文本框中，同时将利用以下代码将Aes类可随机生成的IV和Key（注意IV和Key都是byte[]），转换为base64后分别填写到“向量(IV)”和“密钥(Key)”中。<br>
```C#
private void button1_Click(object sender, EventArgs e)
{
    using (Aes myAes = Aes.Create())
    {
        AesEncryptExtension aes = new AesEncryptExtension();
        textBox2.Text = aes.Encrypt(textBox1.Text, myAes.Key, myAes.IV);
        textBox3.Text = Convert.ToBase64String(myAes.IV);
        textBox4.Text = Convert.ToBase64String(myAes.Key);
    }
    Form3 form = new Form3();
    form.Show();
}

```

　　2.第一步完成后，同时会弹出“接收密文”窗体,如下图。将“玩玩解密”窗体中的“已加密”、“向量（IV）”和“密钥（key）”填写到“接收密文”窗体对应文本框中，将获取到未加密的普通文本。<br>

　　3.以上所示，是手动填写密文、IV和key来获取内容。当然你也可以自动传过去，只要两个系统的iv和key相同就可以实现解密，前提是两个系统中的动态密钥规律要相同，说到这里我想聪明的你应该已经知道Aes加密怎么玩了，好好想想，可以有多种应用。<br>
　　举个例子，图例解释，IV和key合称为钥匙，IV和Key生成算法称为钥匙机，每一把被生产出来的钥匙都刻着钥匙编号，Aes本身称为保险柜，被加密内容则会被放进“保险柜”。两方同时使用钥匙机生产钥匙，每一把钥匙都刻着钥匙编号，运输的时候只运输保险柜和钥匙编号，接收到保险柜的一方，用钥匙编号从钥匙机中拿钥匙打开保险柜，取得加密内容。以上例可称为一个较为简单的Aes应用方式。

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Security.Cryptography;
using System.Text;
using System.Threading.Tasks;

namespace AesEncrypt
{
    /// <summary>
    /// Aes加密算法适用于固定的加解密
    /// </summary>
    public static class AesEncrypt
    {
        /// <summary>
        /// 对称算法的密钥
        /// </summary>
        private readonly static byte[] aesKey = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32 };
        /// <summary>
        /// 对称算法的初始化向量
        /// </summary>
        private readonly static byte[] aesIV = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 };


        /// <summary>
        /// 加密
        /// </summary>
        /// <param name="Text">被加密的字符串</param>
        /// <returns>Base64</returns>
        public static string Encrypt(string Text)
        {
            byte[] encrypted;
            encrypted = EncryptStringToBytes_Aes(Text, aesKey, aesIV);
            return Convert.ToBase64String(encrypted);
        }


        private static byte[] EncryptStringToBytes_Aes(string plainText, byte[] Key, byte[] IV)
        {
            // Check arguments.
            if (plainText == null || plainText.Length <= 0)
            {
                throw new ArgumentNullException("plainText");
            }
            if (Key == null || Key.Length <= 0)
            {
                throw new ArgumentNullException("Key");
            }
            if (IV == null || IV.Length <= 0)
            {
                throw new ArgumentNullException("IV");
            }
            byte[] encrypted;
            // Create an Aes object
            // with the specified key and IV.
            using (Aes aesAlg = Aes.Create())
            {
                aesAlg.Key = Key;
                aesAlg.IV = IV;

                // Create a decrytor to perform the stream transform.
                ICryptoTransform encryptor = aesAlg.CreateEncryptor(aesAlg.Key, aesAlg.IV);

                // Create the streams used for encryption.
                using (MemoryStream msEncrypt = new MemoryStream())
                {
                    using (CryptoStream csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write))
                    {
                        using (StreamWriter swEncrypt = new StreamWriter(csEncrypt))
                        {

                            //Write all data to the stream.
                            swEncrypt.Write(plainText);
                        }
                        encrypted = msEncrypt.ToArray();
                    }
                }
            }
            // Return the encrypted bytes from the memory stream.
            return encrypted;
        }


        /// <summary>
        /// 解密
        /// </summary>
        /// <param name="text">被Aes加密后的Base64</param>
        /// <returns>字符串</returns>
        public static string Decrypt(string text)
        {
            string roundtrip;

            byte[] myByte = Convert.FromBase64String(text);
            roundtrip = DecryptStringFromBytes_Aes(myByte, aesKey, aesIV);

            return roundtrip;
        }
        private static string DecryptStringFromBytes_Aes(byte[] cipherText, byte[] Key, byte[] IV)
        {
            // Check arguments.
            if (cipherText == null || cipherText.Length <= 0)
            {
                throw new ArgumentNullException("cipherText");
            }
            if (Key == null || Key.Length <= 0)
            {
                throw new ArgumentNullException("Key");
            }
            if (IV == null || IV.Length <= 0)
            {
                throw new ArgumentNullException("IV");
            }
            // Declare the string used to hold
            // the decrypted text.
            string plaintext;

            // Create an Aes object
            // with the specified key and IV.
            using (Aes aesAlg = Aes.Create())
            {
                aesAlg.Key = Key;
                aesAlg.IV = IV;

                // Create a decrytor to perform the stream transform.
                ICryptoTransform decryptor = aesAlg.CreateDecryptor(aesAlg.Key, aesAlg.IV);

                // Create the streams used for decryption.
                using (MemoryStream msDecrypt = new MemoryStream(cipherText))
                {
                    using (CryptoStream csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read))
                    {
                        using (StreamReader srDecrypt = new StreamReader(csDecrypt))
                        {

                            // Read the decrypted bytes from the decrypting stream
                            // and place them in a string.
                            plaintext = srDecrypt.ReadToEnd();
                        }
                    }
                }
            }
            return plaintext;
        }
    }
}

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Security.Cryptography;
using System.Text;
using System.Threading.Tasks;

namespace AesEncrypt
{
    /// <summary>
    /// Aes扩展方法
    /// </summary>
    public class AesEncryptExtension
    {

        /// <summary>
        /// 加密
        /// </summary>
        /// <param name="Text">被加密的字符串</param>
        /// <param name="aesKey">对称算法的密钥</param>
        /// <param name="aesIV">设置对称算法的初始化向量</param>
        /// <returns>Base64</returns>
        public string Encrypt(string Text, byte[] aesKey, byte[] aesIV)
        {
            byte[] encrypted;
            encrypted = EncryptStringToBytes_Aes(Text, aesKey, aesIV);
            return Convert.ToBase64String(encrypted);
        }


        private byte[] EncryptStringToBytes_Aes(string plainText, byte[] Key, byte[] IV)
        {
            // Check arguments.
            if (plainText == null || plainText.Length <= 0)
            {
                throw new ArgumentNullException("plainText");
            }
            if (Key == null || Key.Length <= 0)
            {
                throw new ArgumentNullException("Key");
            }
            if (IV == null || IV.Length <= 0)
            {
                throw new ArgumentNullException("IV");
            }
            byte[] encrypted;
            // Create an Aes object
            // with the specified key and IV.
            using (Aes aesAlg = Aes.Create())
            {
                aesAlg.Key = Key;
                aesAlg.IV = IV;

                // Create a decrytor to perform the stream transform.
                ICryptoTransform encryptor = aesAlg.CreateEncryptor(aesAlg.Key, aesAlg.IV);

                // Create the streams used for encryption.
                using (MemoryStream msEncrypt = new MemoryStream())
                {
                    using (CryptoStream csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write))
                    {
                        using (StreamWriter swEncrypt = new StreamWriter(csEncrypt))
                        {

                            //Write all data to the stream.
                            swEncrypt.Write(plainText);
                        }
                        encrypted = msEncrypt.ToArray();
                    }
                }
            }
            // Return the encrypted bytes from the memory stream.
            return encrypted;
        }


        /// <summary>
        /// 解密
        /// </summary>
        /// <param name="text">被Aes加密后的Base64</param>
        /// <param name="aesKey">对称算法的密钥</param>
        /// <param name="aesIV">设置对称算法的初始化向量</param>
        /// <returns>字符串</returns>
        public string Decrypt(string text, byte[] aesKey, byte[] aesIV)
        {
            string roundtrip;

            byte[] myByte = Convert.FromBase64String(text);
            roundtrip = DecryptStringFromBytes_Aes(myByte, aesKey, aesIV);

            return roundtrip;
        }
        private string DecryptStringFromBytes_Aes(byte[] cipherText, byte[] Key, byte[] IV)
        {
            // Check arguments.
            if (cipherText == null || cipherText.Length <= 0)
            {
                throw new ArgumentNullException("cipherText");
            }
            if (Key == null || Key.Length <= 0)
            {
                throw new ArgumentNullException("Key");
            }
            if (IV == null || IV.Length <= 0)
            {
                throw new ArgumentNullException("IV");
            }
            // Declare the string used to hold
            // the decrypted text.
            string plaintext;

            // Create an Aes object
            // with the specified key and IV.
            using (Aes aesAlg = Aes.Create())
            {
                aesAlg.Key = Key;
                aesAlg.IV = IV;

                // Create a decrytor to perform the stream transform.
                ICryptoTransform decryptor = aesAlg.CreateDecryptor(aesAlg.Key, aesAlg.IV);

                // Create the streams used for decryption.
                using (MemoryStream msDecrypt = new MemoryStream(cipherText))
                {
                    using (CryptoStream csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read))
                    {
                        using (StreamReader srDecrypt = new StreamReader(csDecrypt))
                        {

                            // Read the decrypted bytes from the decrypting stream
                            // and place them in a string.
                            plaintext = srDecrypt.ReadToEnd();
                        }
                    }
                }
            }
            return plaintext;
        }
    }
}

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Security.Cryptography;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace AesEncrypt
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {

            textBox2.Text = AesEncrypt.Encrypt(textBox1.Text);
        }

        private void button2_Click(object sender, EventArgs e)
        {

            textBox1.Text = AesEncrypt.Decrypt(textBox2.Text);
        }

        private void 玩玩解密ToolStripMenuItem_Click(object sender, EventArgs e)
        {
            Form2 form = new Form2();
            form.Show();
        }
    }
}

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Security.Cryptography;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace AesEncrypt
{
    public partial class Form2 : Form
    {
        public Form2()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            using (Aes myAes = Aes.Create())
            {
                AesEncryptExtension aes = new AesEncryptExtension();
                textBox2.Text = aes.Encrypt(textBox1.Text, myAes.Key, myAes.IV);
                textBox3.Text = Convert.ToBase64String(myAes.IV);
                textBox4.Text = Convert.ToBase64String(myAes.Key);
            }
            Form3 form = new Form3();
            form.Show();
        }
    }
}

using System;
using System.Collections;
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;

namespace AesEncrypt
{
    public partial class Form3 : Form
    {
        public Form3()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            AesEncryptExtension aes = new AesEncryptExtension();
            byte[] aesIV = Convert.FromBase64String(textBox3.Text);
            byte[] aesKey = Convert.FromBase64String(textBox4.Text);

            textBox1.Text = aes.Decrypt(textBox2.Text, aesKey, aesIV);
        }
    }
}

Advanced Encryption Standard，缩写：AES），在密码学中又称Rijndael加密法