From 99a1527555cc281f1391a7a30b8c4f7c566d7cd1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E6=BD=87=E9=98=B3=20=E9=82=B9?= <wanna_zxy@yeah.net>
Date: Sat, 23 Dec 2023 11:17:45 +0800
Subject: [PATCH] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=E6=96=87=E4=BB=B6=E5=8A=A0?=
 =?UTF-8?q?=E5=AF=86=E7=AE=97=E6=B3=95?=
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---
 Elight.Utility/Encrypt/DataEncryption.cs | 175 +++++++++++++++++++++++
 1 file changed, 175 insertions(+)
 create mode 100644 Elight.Utility/Encrypt/DataEncryption.cs

diff --git a/Elight.Utility/Encrypt/DataEncryption.cs b/Elight.Utility/Encrypt/DataEncryption.cs
new file mode 100644
index 0000000..b87f403
--- /dev/null
+++ b/Elight.Utility/Encrypt/DataEncryption.cs
@@ -0,0 +1,175 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Elight.Utility.Encrypt
+{
+    public sealed class DataEncryption
+    {
+        private static byte[] KEY = new byte[8] { 40, 16, 37, 37, 32, 62, 83, 60 };
+
+        private static byte ByteXor(byte b, byte key)
+        {
+            b = (byte)(b ^ key);
+            return b;
+        }
+
+        private static byte[] ByteXor(byte[] data, byte[] key)
+        {
+            var keyLen = key.Length;
+            var dataLen = data.Length;
+            if (dataLen == 0)
+            {
+                return data;
+            }
+            for (var i = 0; i < dataLen; i++)
+            {
+                data[i] = ByteXor(data[i], key[i % keyLen]);
+            }
+            return data;
+        }
+
+        /// <summary>
+        /// 加密，key必须是2的n次方
+        /// </summary>
+        public static byte[] Encryption(byte[] data, byte[] key)
+        {
+            return ByteXor(data, key);
+        }
+
+        /// <summary>
+        /// 加密, 使用内置密钥
+        /// </summary>
+        public static byte[] Encryption(byte[] data)
+        {
+            return ByteXor(data, KEY);
+        }
+
+        /// <summary>
+        /// 加密文件
+        /// </summary>
+        /// <param name="srcFile">明文文件</param>
+        /// <param name="descFile">密文文件</param>
+        /// <param name="key">密钥</param>
+        public static void Encryption(string srcFile, string descFile, byte[] key)
+        {
+            var fs = File.OpenRead(srcFile);
+            var newfs = File.Create(descFile, 1024 * 512);
+            var count = 0;
+            var keyLen = key.Length;
+
+            var buffer = new byte[1024 * 512];
+            using (fs)
+            {
+                using (newfs)
+                {
+                    if (fs.Length == 0)
+                    {
+                        return;
+                    }
+                    while (fs.Position < fs.Length)
+                    {
+                        count = fs.Read(buffer, 0, 1024 * 512);
+                        for (var i = 0; i < count; i++)
+                        {
+                            buffer[i] = ByteXor(buffer[i], key[i % keyLen]);
+                        }
+                        newfs.Write(buffer, 0, count);
+                    }
+                }
+            }
+        }
+
+        /// <summary>
+        /// 加密文件, 使用内置密钥
+        /// </summary>
+        /// <param name="srcFile">明文文件</param>
+        /// <param name="descFile">密文文件</param>
+        public static void Encryption(string srcFile, string descFile)
+        {
+            Encryption(srcFile, descFile, KEY);
+        }
+
+        /// <summary>
+        /// 解密
+        /// </summary>
+        public static byte[] Decryption(byte[] data, byte[] key)
+        {
+            return ByteXor(data, key);
+        }
+
+        /// <summary>
+        /// 解密, 使用内置密钥
+        /// </summary>
+        public static byte[] Decryption(byte[] data)
+        {
+            return ByteXor(data, KEY);
+        }
+
+        /// <summary>
+        /// 解密文件
+        /// </summary>
+        /// <param name="srcFile">密文文件</param>
+        /// <param name="descFile">解密后的文件</param>
+        /// <param name="key">密钥</param>
+        public static void Decryption(string srcFile, string descFile, byte[] key)
+        {
+            Encryption(srcFile, descFile, key);
+        }
+
+        /// <summary>
+        /// 解密文件, 使用内置密钥 
+        /// </summary>
+        /// <param name="srcFile">密文文件</param>
+        /// <param name="descFile">解密后的文件</param>
+        public static void Decryption(string srcFile, string descFile)
+        {
+            Decryption(srcFile, descFile, KEY);
+        }
+
+        /// <summary>
+        /// 根据文件路径判断是否加密文件
+        /// </summary>
+        /// <param name="srcFile">文件路径</param>
+        /// <returns></returns>
+        public static bool JudgeIsEncryFile(string srcFile)
+        {
+            return srcFile.LastIndexOf(".encry") > 0;
+        }
+
+        public static string Decryptiones(string srcFile)
+        {
+            var fs = File.OpenRead(srcFile);
+            //var newfs = File.Create(descFile, 1024 * 512);
+            var newfs = new MemoryStream();
+            var count = 0;
+            var keyLen = KEY.Length;
+
+            var buffer = new byte[1024 * 512];
+            using (fs)
+            {
+                using (newfs)
+                {
+                    if (fs.Length == 0)
+                    {
+                        return null;
+                    }
+                    while (fs.Position < fs.Length)
+                    {
+                        count = fs.Read(buffer, 0, 1024 * 512);
+                        for (var i = 0; i < count; i++)
+                        {
+                            buffer[i] = ByteXor(buffer[i], KEY[i % keyLen]);
+                        }
+                        newfs.Write(buffer, 0, count);
+                    }
+                }
+            }
+
+            var base64 = Convert.ToBase64String(newfs.ToArray());
+            return base64;
+        }
+    }
+}