Don't request all access for OpenSCManager

LibreHardwareMonitorLib/Hardware/KernelDriver.cs

@@ -25,17 +25,15 @@ internal class KernelDriver
         _driverId = driverId;
     }
 
-    public bool IsOpen
-    {
-        get { return _device != null; }
-    }
+    public bool IsOpen => _device != null;
 
     public bool Install(string path, out string errorMessage)
     {
-        IntPtr manager = AdvApi32.OpenSCManager(null, null, AdvApi32.SC_MANAGER_ACCESS_MASK.SC_MANAGER_ALL_ACCESS);
+        IntPtr manager = AdvApi32.OpenSCManager(null, null, AdvApi32.SC_MANAGER_ACCESS_MASK.SC_MANAGER_CREATE_SERVICE);
         if (manager == IntPtr.Zero)
         {
-            errorMessage = "OpenSCManager returned zero.";
+            int errorCode = Marshal.GetLastWin32Error();
+            errorMessage = $"OpenSCManager returned the error code: {errorCode:X8}.";
             return false;
         }
 
@@ -55,24 +53,24 @@ internal class KernelDriver
 
         if (service == IntPtr.Zero)
         {
-            int error = Marshal.GetHRForLastWin32Error();
-            if (error == Kernel32.ERROR_SERVICE_EXISTS)
+            int errorCode = Marshal.GetLastWin32Error();
+            if (errorCode == Kernel32.ERROR_SERVICE_EXISTS)
             {
                 errorMessage = "Service already exists";
                 return false;
             }
 
-            errorMessage = "CreateService returned the error: " + Marshal.GetExceptionForHR(error).Message;
+            errorMessage = $"CreateService returned the error code: {errorCode:X8}.";
             AdvApi32.CloseServiceHandle(manager);
             return false;
         }
 
         if (!AdvApi32.StartService(service, 0, null))
         {
-            int error = Marshal.GetHRForLastWin32Error();
-            if (error != Kernel32.ERROR_SERVICE_ALREADY_RUNNING)
+            int errorCode = Marshal.GetLastWin32Error();
+            if (errorCode != Kernel32.ERROR_SERVICE_ALREADY_RUNNING)
             {
-                errorMessage = "StartService returned the error: " + Marshal.GetExceptionForHR(error).Message;
+                errorMessage = $"StartService returned the error code: {errorCode:X8}.";
                 AdvApi32.CloseServiceHandle(service);
                 AdvApi32.CloseServiceHandle(manager);
                 return false;
@@ -101,23 +99,17 @@ internal class KernelDriver
     public bool Open()
     {
         IntPtr fileHandle = Kernel32.CreateFile(@"\\.\" + _driverId, 0xC0000000, FileShare.None, IntPtr.Zero, FileMode.Open, FileAttributes.Normal, IntPtr.Zero);
+
         _device = new SafeFileHandle(fileHandle, true);
         if (_device.IsInvalid)
-        {
-            _device.Close();
-            _device.Dispose();
-            _device = null;
-        }
+            Close();
 
         return _device != null;
     }
 
     public bool DeviceIOControl(Kernel32.IOControlCode ioControlCode, object inBuffer)
     {
-        if (_device == null)
-            return false;
-
-        return Kernel32.DeviceIoControl(_device, ioControlCode, inBuffer, inBuffer == null ? 0 : (uint)Marshal.SizeOf(inBuffer), null, 0, out uint _, IntPtr.Zero);
+        return _device != null && Kernel32.DeviceIoControl(_device, ioControlCode, inBuffer, inBuffer == null ? 0 : (uint)Marshal.SizeOf(inBuffer), null, 0, out uint _, IntPtr.Zero);
     }
 
     public bool DeviceIOControl<T>(Kernel32.IOControlCode ioControlCode, object inBuffer, ref T outBuffer)
@@ -170,7 +162,7 @@ internal class KernelDriver
 
     public bool Delete()
     {
-        IntPtr manager = AdvApi32.OpenSCManager(null, null, AdvApi32.SC_MANAGER_ACCESS_MASK.SC_MANAGER_ALL_ACCESS);
+        IntPtr manager = AdvApi32.OpenSCManager(null, null, AdvApi32.SC_MANAGER_ACCESS_MASK.SC_MANAGER_CONNECT);
         if (manager == IntPtr.Zero)
             return false;
 
@@ -189,4 +181,4 @@ internal class KernelDriver
 
         return true;
     }
-}
+}

LibreHardwareMonitorLib/Hardware/Ring0.cs

@@ -72,7 +72,7 @@ internal static class Ring0
                     }
                     else
                     {
-                        _report.Append("Status: Installing driver \"").Append(_filePath).Append("\" failed").AppendLine(File.Exists(_filePath) ? " and file exists" : string.Empty);
+                        _report.Append($"Status: Installing driver \"{_filePath}\" failed").AppendLine(File.Exists(_filePath) ? " and file exists" : string.Empty);
                         _report.Append("First Exception: ").AppendLine(installError);
                         _report.Append("Second Exception: ").AppendLine(secondError);
                     }
@@ -205,7 +205,9 @@ internal static class Ring0
             _filePath = null;
         }
         catch
-        { }
+        {
+            // Ignored.
+        }
     }
 
     private static string GetServiceName()
@@ -251,7 +253,7 @@ internal static class Ring0
 
     private static string GetFilePath()
     {
-        string filePath;
+        string filePath = null;
 
         try
         {
@@ -259,7 +261,7 @@ internal static class Ring0
             if (!string.IsNullOrEmpty(processModule?.FileName))
             {
                 filePath = Path.ChangeExtension(processModule.FileName, ".sys");
-                if (TryCreate(filePath))
+                if (CanCreate(filePath))
                     return filePath;
             }
         }
@@ -268,12 +270,14 @@ internal static class Ring0
             // Continue with the other options.
         }
 
+        string previousFilePath = filePath;
         filePath = GetPathFromAssembly(Assembly.GetExecutingAssembly());
-        if (!string.IsNullOrEmpty(filePath) && TryCreate(filePath))
+        if (previousFilePath != filePath && !string.IsNullOrEmpty(filePath) && CanCreate(filePath))
             return filePath;
 
+        previousFilePath = filePath;
         filePath = GetPathFromAssembly(typeof(Ring0).Assembly);
-        if (!string.IsNullOrEmpty(filePath) && TryCreate(filePath))
+        if (previousFilePath != filePath && !string.IsNullOrEmpty(filePath) && CanCreate(filePath))
             return filePath;
 
         try
@@ -282,7 +286,7 @@ internal static class Ring0
             if (!string.IsNullOrEmpty(filePath))
             {
                 filePath = Path.ChangeExtension(filePath, ".sys");
-                if (TryCreate(filePath))
+                if (CanCreate(filePath))
                     return filePath;
             }
         }
@@ -306,11 +310,11 @@ internal static class Ring0
             }
         }
 
-        static bool TryCreate(string path)
+        static bool CanCreate(string path)
         {
             try
             {
-                using (File.Create(path))
+                using (File.Create(path, 1, FileOptions.DeleteOnClose))
                     return true;
             }
             catch

LibreHardwareMonitorLib/Interop/AdvApi32.cs

@@ -14,7 +14,7 @@ internal class AdvApi32
 {
     private const string DllName = "advapi32.dll";
 
-    [DllImport(DllName, CallingConvention = CallingConvention.Winapi)]
+    [DllImport(DllName, SetLastError = true, CallingConvention = CallingConvention.Winapi)]
     [DefaultDllImportSearchPaths(DllImportSearchPath.System32)]
     internal static extern IntPtr OpenSCManager(string lpMachineName, string lpDatabaseName, SC_MANAGER_ACCESS_MASK dwDesiredAccess);
 
@@ -147,4 +147,4 @@ internal class AdvApi32
         public uint dwCheckPoint;
         public uint dwWaitHint;
     }
-}
+}