Fork me on GitHub

C# AES加解密

        #region AES加密
        /// <summary>
        /// 加密数据
        /// </summary>
        /// <param name="input">加密前的字符串</param>
        /// <returns>加密后的字符串</returns>
        public static string AESEncrypt(string input)
        {
            //盐值
            string saltValue = "saltValue";
            //密码值
            string pwdValue = "pwdValue";

            byte[] data = System.Text.UTF8Encoding.UTF8.GetBytes(input);
            byte[] salt = System.Text.UTF8Encoding.UTF8.GetBytes(saltValue);

            //AesManaged - 高级加密标准(AES) 对称算法的管理类
            System.Security.Cryptography.AesManaged aes = new System.Security.Cryptography.AesManaged();

            //Rfc2898DeriveBytes - 通过使用基于 HMACSHA1 的伪随机数生成器,实现基于密码的密钥派生功能 (PBKDF2 - 一种基于密码的密钥派生函数)
            //通过 密码 和 salt 派生密钥
            System.Security.Cryptography.Rfc2898DeriveBytes rfc = new System.Security.Cryptography.Rfc2898DeriveBytes(pwdValue, salt);

            /* 
             * AesManaged.BlockSize - 加密操作的块大小(单位:bit)
             * AesManaged.LegalBlockSizes - 对称算法支持的块大小(单位:bit)
             * AesManaged.KeySize - 对称算法的密钥大小(单位:bit)
             * AesManaged.LegalKeySizes - 对称算法支持的密钥大小(单位:bit)
             * AesManaged.Key - 对称算法的密钥
             * AesManaged.IV - 对称算法的密钥大小
             * Rfc2898DeriveBytes.GetBytes(int 需要生成的伪随机密钥字节数) - 生成密钥
            */

            aes.BlockSize = aes.LegalBlockSizes[0].MaxSize;
            aes.KeySize = aes.LegalKeySizes[0].MaxSize;
            aes.Key = rfc.GetBytes(aes.KeySize / 8);
            aes.IV = rfc.GetBytes(aes.BlockSize / 8);

            //用当前的 Key 属性和初始化向量 IV 创建对称加密器对象
            System.Security.Cryptography.ICryptoTransform encryptTransform = aes.CreateEncryptor();

            //加密后的输出流
            System.IO.MemoryStream encryptStream = new System.IO.MemoryStream();

            //将加密后的目标流(encryptStream)与加密转换(encryptTransform)相连接
            System.Security.Cryptography.CryptoStream encryptor = new System.Security.Cryptography.CryptoStream
                (encryptStream, encryptTransform, System.Security.Cryptography.CryptoStreamMode.Write);

            //将一个字节序列写入当前 CryptoStream (完成加密的过程)
            encryptor.Write(data, 0, data.Length);
            encryptor.Close();

            // 将加密后所得到的流转换成字节数组,再用Base64编码将其转换为字符串
            string encryptedString = Convert.ToBase64String(encryptStream.ToArray());

            return encryptedString;
        }
        #endregion

        #region AES解密
        /// <summary>
        /// 解密数据
        /// </summary>
        /// <param name="input">加密后的字符串</param>
        /// <returns>加密前的字符串</returns>
        public static string AESDecrypt(string input)
        {
            //盐值(与加密时设置的值一致)
            string saltValue = "saltValue";
            //密码值(与加密时设置的值一致)
            string pwdValue = "pwdValue";

            byte[] encryptBytes = Convert.FromBase64String(input);
            byte[] salt = System.Text.Encoding.UTF8.GetBytes(saltValue);

            System.Security.Cryptography.AesManaged aes = new System.Security.Cryptography.AesManaged();

            System.Security.Cryptography.Rfc2898DeriveBytes rfc = new System.Security.Cryptography.Rfc2898DeriveBytes(pwdValue, salt);

            aes.BlockSize = aes.LegalBlockSizes[0].MaxSize;
            aes.KeySize = aes.LegalKeySizes[0].MaxSize;
            aes.Key = rfc.GetBytes(aes.KeySize / 8);
            aes.IV = rfc.GetBytes(aes.BlockSize / 8);

            //用当前的 Key 属性和初始化向量 IV 创建对称解密器对象
            System.Security.Cryptography.ICryptoTransform decryptTransform = aes.CreateDecryptor();

            //解密后的输出流
            System.IO.MemoryStream decryptStream = new System.IO.MemoryStream();

            //将解密后的目标流(decryptStream)与解密转换(decryptTransform)相连接
            System.Security.Cryptography.CryptoStream decryptor = new System.Security.Cryptography.CryptoStream(
                decryptStream, decryptTransform, System.Security.Cryptography.CryptoStreamMode.Write);

            //将一个字节序列写入当前 CryptoStream (完成解密的过程)
            decryptor.Write(encryptBytes, 0, encryptBytes.Length);
            decryptor.Close();

            //将解密后所得到的流转换为字符串
            byte[] decryptBytes = decryptStream.ToArray();
            string decryptedString = System.Text.UTF8Encoding.UTF8.GetString(decryptBytes, 0, decryptBytes.Length);

            return decryptedString;
        }

        #endregion

 

posted @ 2012-11-12 17:12  Nick.Chung  阅读(789)  评论(0编辑  收藏  举报