From 665d289d3a8fd86b8fd2cdaedd7956ecacfe6b1b Mon Sep 17 00:00:00 2001
From: SCM6WE <Marc-Felix.Schmitz@de.bosch.com>
Date: Thu, 23 Sep 2021 13:33:03 +0200
Subject: [PATCH] brgin of encryption

---
 PolyChat/Controller.cs         | 52 ++++-----------------
 PolyChat/Models/FileManager.cs | 84 ++++++++++++++++++++++++++++++++++
 PolyChat/PolyChat.csproj       |  1 +
 3 files changed, 95 insertions(+), 42 deletions(-)
 create mode 100644 PolyChat/Models/FileManager.cs

diff --git a/PolyChat/Controller.cs b/PolyChat/Controller.cs
index 5f114e6..1d0c322 100644
--- a/PolyChat/Controller.cs
+++ b/PolyChat/Controller.cs
@@ -11,6 +11,9 @@ using System;
 using System.Text.Json;
 using System.Text;
 using System.Security.Cryptography;
+using Windows.Security.Cryptography.Core;
+using Windows.Security.Cryptography;
+using Windows.Storage.Streams;
 
 namespace PolyChat
 {
@@ -37,6 +40,8 @@ namespace PolyChat
         {
             UIController = uiController;
             OwnIP = getIP();
+            loadChats();
+            encode("test");
             Serve();
         }
 
@@ -168,6 +173,8 @@ namespace PolyChat
 
         /// <summary>
         /// sends chatlogs as json array to uiController wit corrosponding ip
+        /// 
+        /// in ui when chat is clicked connection gets established
         /// </summary>
         /// <param name="ip"></param>
         public void loadChats()
@@ -203,41 +210,6 @@ namespace PolyChat
             }
         }
 
-        /*
-        public void loadChat(String ip)
-        {
-            //TODO: also load chatlogs when user tries to connect
-            //load dir and create if non existant
-            if (Directory.Exists("U:\\PolyChat\\Saves"))
-            {
-                Debug.WriteLine("--Path exists.--");
-            }
-            else
-            {
-                Directory.CreateDirectory("U:\\PolyChat\\Saves");
-                Debug.WriteLine("--Path Created--.");
-            }
-
-            //go through all files and send ip and json array to ui
-            String[] filepaths = Directory.GetFiles("U:\\PolyChat\\Saves");
-            if (filepaths.Length > 0)
-            {
-                Debug.WriteLine("---Loading Saves");
-                foreach (String path in filepaths)
-                {
-                    Debug.WriteLine($"--{path}");
-                    String jsonArr = File.ReadAllText(path);
-                    String ip = Path.GetFileName(path);
-                    ip = ip.Substring(0, ip.Length - 4);
-                    Debug.WriteLine($"-{ip}");
-                    Debug.WriteLine(jsonArr);
-                    Connect(ip);
-                    UIController.OnIncomingConnection(ip);
-                    UIController.OnIncomingMessages(ip, jsonArr);
-                }
-            }
-        }
-        */
         /// <summary>
         /// Saves incoming chat message to 
         /// </summary>
@@ -296,13 +268,9 @@ namespace PolyChat
 
         private void encode(string json)
         {
-            byte[] plaintext = Encoding.UTF8.GetBytes(json);
-            byte[] entropy = new byte[20];
-            using (RNGCryptoServiceProvider rng = new RNGCryptoServiceProvider())
-            {
-                rng.GetBytes(entropy);
-            }
-
+            String ecryptetText = FileManager.encrypt(json);
+            Debug.WriteLine(ecryptetText);
+            //Debug.WriteLine(FileManager.decrypt(ecryptetText));
         }
     }
 }
diff --git a/PolyChat/Models/FileManager.cs b/PolyChat/Models/FileManager.cs
new file mode 100644
index 0000000..815873c
--- /dev/null
+++ b/PolyChat/Models/FileManager.cs
@@ -0,0 +1,84 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using System.IO;
+using System.Security.Cryptography;
+
+
+namespace PolyChat.Models
+{
+    class FileManager
+    {
+        public static String encrypt(String toEncrypt)
+        {
+            try {
+                string textToEncrypt = toEncrypt;
+                string ToReturn = "";
+                string publickey = "santhosh";
+                string secretkey = "engineer";
+                byte[] secretkeyByte = { };
+                secretkeyByte = System.Text.Encoding.UTF8.GetBytes(secretkey);
+                byte[] publickeybyte = { };
+                publickeybyte = System.Text.Encoding.UTF8.GetBytes(publickey);
+                MemoryStream ms = null;
+                CryptoStream cs = null;
+                byte[] inputbyteArray = System.Text.Encoding.UTF8.GetBytes(textToEncrypt);
+                using (DESCryptoServiceProvider des = new DESCryptoServiceProvider())
+                {
+                    ms = new MemoryStream();
+                    cs = new CryptoStream(ms, des.CreateEncryptor(publickeybyte, secretkeyByte), CryptoStreamMode.Write);
+                    cs.Write(inputbyteArray, 0, inputbyteArray.Length);
+                    cs.FlushFinalBlock();
+                    ToReturn = Convert.ToBase64String(ms.ToArray());
+                }
+                return ToReturn;
+            } catch (Exception ex)
+            {
+                throw new Exception(ex.Message, ex.InnerException);
+            }
+
+        }
+
+
+        public static String decrypt(String toDecrypt)
+        {
+            try
+            {
+                string textToDecrypt = toDecrypt;
+                string ToReturn = "";
+                string publickey = "santhosh";
+                string privatekey = "engineer";
+                byte[] privatekeyByte = { };
+                privatekeyByte = System.Text.Encoding.UTF8.GetBytes(privatekey);
+                byte[] publickeybyte = { };
+                publickeybyte = System.Text.Encoding.UTF8.GetBytes(publickey);
+                MemoryStream ms = null;
+                CryptoStream cs = null;
+                byte[] inputbyteArray = new byte[textToDecrypt.Replace(" ", "+").Length];
+                inputbyteArray = Convert.FromBase64String(textToDecrypt.Replace(" ", "+"));
+                using (DESCryptoServiceProvider des = new DESCryptoServiceProvider())
+                {
+                    ms = new MemoryStream();
+                    cs = new CryptoStream(ms, des.CreateDecryptor(publickeybyte, privatekeyByte), CryptoStreamMode.Write);
+                    cs.Write(inputbyteArray, 0, inputbyteArray.Length);
+                    cs.FlushFinalBlock();
+                    Encoding encoding = Encoding.UTF8;
+                    ToReturn = encoding.GetString(ms.ToArray());
+                }
+                return ToReturn;
+            }
+            catch (Exception ae)
+            {
+                throw new Exception(ae.Message, ae.InnerException);
+            }
+        }
+    }
+
+
+
+
+
+
+}
diff --git a/PolyChat/PolyChat.csproj b/PolyChat/PolyChat.csproj
index 12041a4..c047509 100644
--- a/PolyChat/PolyChat.csproj
+++ b/PolyChat/PolyChat.csproj
@@ -137,6 +137,7 @@
     <Compile Include="Models\ChatPartner.cs" />
     <Compile Include="Models\Exceptions\MessageTimedOutException.cs" />
     <Compile Include="Models\Exceptions\ConnectionFailedException.cs" />
+    <Compile Include="Models\FileManager.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
     <Compile Include="Util\IP.cs" />
     <Compile Include="Views\Dialog.xaml.cs">