baseline: OpenMU upstream b5a0961 (fresh source)

src/ClientErrorLogDecryptor/Program.cs

@@ -0,0 +1,41 @@
+// <copyright file="Program.cs" company="MUnique">
+// Licensed under the MIT License. See LICENSE file in the project root for full license information.
+// </copyright>
+
+using System.IO;
+
+var logPath = args.FirstOrDefault();
+if (string.IsNullOrWhiteSpace(logPath))
+{
+    Console.WriteLine("No path to the error log specified as first parameter. Press any key to exit...");
+    Console.ReadKey();
+    return;
+}
+
+var decryptionKey = new byte[] { 0x7C, 0xBD, 0x81, 0x9F, 0x3D, 0x93, 0xE2, 0x56, 0x2A, 0x73, 0xD2, 0x3E, 0xF2, 0x83, 0x95, 0xBF };
+try
+{
+    var fileBytes = await File.ReadAllBytesAsync(logPath).ConfigureAwait(false);
+
+    var resultBuilder = new StringBuilder();
+    var i = 0;
+    foreach (var character in fileBytes)
+    {
+        var result = (char)(character ^ decryptionKey[i % decryptionKey.Length]);
+        resultBuilder.Append(result);
+        i++;
+    }
+
+    var resultPath = logPath + ".decrypted.txt";
+    File.WriteAllText(resultPath, resultBuilder.ToString());
+    Console.WriteLine($"Decrypted file has been written to {resultPath}. Press any key to exit...");
+}
+catch (Exception ex)
+{
+    Console.WriteLine($"Unexpected error during decrypting the file '{logPath}':");
+    Console.WriteLine(ex);
+
+    Console.WriteLine($"Press any key to exit...");
+}
+
+Console.ReadKey();