HidHide

Introduction

Microsoft Windows offers support for a wide range of human interface devices, like joysticks and game pads. Associating the buttons and axes of these devices with application specific behavior, such as Fire, Roll, or Pitch is however left to the individual application developers to realize.

While there are good examples of applications allowing a user to customize the controls to their liking, other applications are less sophisticated or lack just that feature a user is looking for. This is where utilities like vJoy and Joystick Gremlin come to the rescue. These utilities aren't limited by a vendor lock-in and attempt to move certain features back into the domain of the operating system. Once properly arranged, a feature becomes universally available for a wide range of applications.

A technique used by these utilities is to use a feeder application that listens to the physical devices on a system, and in turn controls one or more virtual devices where the game or application is listening to. Mapping physical devices to a virtual device allows for e.g. dual joystick support in games that only support a single joystick, or enable multiple devices to bind to the one and same function in a game that only supports single controller bindings.

While this approach offers a lot of advantages, it also comes with a side effect. Most applications record the user interactions while binding a function with a control or button press. When a virtual device is used, the application receives input from two devices simultaneously. It will be notified by both the physical device triggered, and the virtual device that acts in turn! Some feeders have an option to spam the application repeatedly; however, that approach is cumbersome and error prone.

With HidHide it is possible to deny a specific application access to one or more human interface devices, effectively hiding a device from the application. When a HOTAS is preferred for a flight-simulator one can hide the game pads. When a steering wheel is preferred for a racing game, one can hide the joysticks, and so on. When, as mentioned above, a feeder utility is used, one can use HidHide to hide the physical device from the application, hence avoiding multiple notifications while binding game functions and device controls.

Package content

HidHide is a kernel-mode filter driver available for Windows 10 or higher (KMDF 1.13+). It comes with a configuration utility via which the driver is configured and controlled. The filter driver starts automatically and runs unattended with system privileges. A system reboot may be triggered after driver installation or removal. The configuration utility runs in the least privileged mode and doesn't require elevated rights.

User guide

The configuration utility allows you to:

• Enable or disable the service
• Specify which applications may look through the cloak
• Specify the human interface devices that should be hidden from ordinary applications

The main dialog of the configuration utility offers two main tabs.

The Applications tab shows all white-listed applications that are allowed access to the hidden devices. Typically listed here are vendor-specific utilities for configuring the human interface devices, and feeder utilities. Entries can be added to the list by pressing +. Select one or more entries with the shift and/or control key and press - to remove entries from the list. Notice that the client replaces a logical drive letter by a full path. This is intentionally and offers some resilience for changes in logical drive mapping.

Per default, the Devices tab lists all Gaming devices currently connected to the system. The list refreshes automatically when a new device is detected. The dialog offers two check boxes for filtering.

Via Filter-out disconnected one can extend the list with devices that were connected earlier to the system but are currently not present. With Gaming devices only one can limit the list to game pads and joysticks only. This feature relies on proper information from the device vendors. Some vendors however use vendor-specific codes. Be sure to switch off this filter should you notice that your gaming device seems absent in the list. The filters are ignored for devices that are selected for hiding, so that one has a complete overview on the hidden devices.

Last but not least, the Enable device hiding check box provides control over the HidHide service. When enabled it blocks access to the black-listed devices unless the application is explicitly white-listed. When disabled, all applications are granted access to all devices.

An entry in the list can be expanded to reveal the composite devices associated with a device and offers fine-grained control over a device. HidHide uses the selection also for a secondary purpose. Some legacy applications ignore the human interface device layer offered by the operating system and instead interact with the underlying device driver. Access to the underlying driver will be blocked when a device only has composite HID devices, and all are selected.

The expanded list may mark entries as absent or denied. absent entries appear when the device characteristics are altered. These are residual entries in the caches of the operating system, and can be cleaned-up using utilities like Device Cleanup Tool. denied entries appear for hidden devices when the configuration utility itself is not whilelisted.

Package integration

Installation packages and third-party applications can rely on the following two registry keys. "HKCR\Installer\Dependencies\NSS.Drivers.HidHide.x64\Version" signals the availability of HidHide and its version. "HKCR\SOFTWARE\Nefarius Software Solutions e.U.\Nefarius Software Solutions e.U. HidHide\Path" tells its location.

Third-party software deployment may benefit from the HidHide Command Line Interface (CLI) while deploying software. Please be conservative while altering a clients' configuration and only extend the configuration with new features offered. Don't assume exclusive ownership of the configuration settings as a recovery typically requires manual actions by the user.

Bugs & Features

Found a bug and want it fixed? Feel free to open a detailed issue on the GitHub issue tracker!

HidHide provides both logging and tracing. Logging can be found the Event Viewer under Windows Logs and System. Tracing can be found under Applications and Services Logs and Nefarius after enabling Show Analytic and Debug Logs. Extended tracing is available but switched off per default for performance reasons. Tracing is controlled using the wevtutil utility which is an integral part of the operating system. To enable extended tracing, open a command shell, and enter the following;

wevtutil set-log Nefarius-Drivers-HidHide/Diagnostic /e:false
wevtutil set-log Nefarius-Drivers-HidHide/Diagnostic /k:5
wevtutil set-log Nefarius-Drivers-HidHide/Diagnostic /e:true

Tracing adjustments remain in affect after a reboot. Restore tracing to its default level using the above sequence with /k:1 instead. Tracing to the debug console is enabled with /k:3 and /k:7 respectively.

Questions & Support

Please respect that the GitHub issue tracker isn't a help desk. Look at the community support resources.

Donations

Creating a utility like this requires time and dedication. Should you like to express your gratitude, consider a pledge for a game I'm rather fond of; the biggest crowd funded game currently in development Star Citizen. Be sure to apply a referral code at account creation as it gives a bit more in-game currency and can't be applied later on. My referral code is STAR-K6S5-KPY7 should you seek one. Have fun and see you in the verse!