SL-HWID Integration Guide

SL-HWID

SL-HWID is a fault-tolerant, cross-platform hardware identifier for C++20 and .NET 8 applications. Instead of treating one serial number as the whole machine, it derives a random device identifier from a set of hardware and software signals. That lets ordinary changes such as replacing a monitor leave the identifier intact, while making a single-value spoof less useful.

It is useful with System Locker and with other licensing systems. In either case, send the generated value to your authorization service and call commit only after that service accepts the machine. The commit re-centers the local recovery data around any ordinary hardware drift.

The source, license, and full cross-platform notes are available in the SL-HWID repository.

Before you start

SL-HWID stores local recovery data. On Windows, it uses HKLM\SOFTWARE\SystemLocker when it can write there, and otherwise uses the current user's registry hive. Do not delete that state as part of normal cleanup. Deleting it, or deliberately using ForceReenroll / forceReenroll, creates a new HWID that needs a server-side device reset or reactivation.

Visual Studio: C++20

The C++ library is a CMake project with no third-party dependencies. Use Visual Studio 2022 with the Desktop development with C++ workload and CMake 3.20 or later.

1. Clone or download SL-HWID into your project, for example at external/SL-HWID.
2. Open your CMake project folder in Visual Studio.
3. Add the library to your top-level CMakeLists.txt, then let Visual Studio reload CMake.
4. Build your application from Build > Build All.

cmake_minimum_required(VERSION 3.20)
project(LicenseApp LANGUAGES CXX)

add_subdirectory(external/SL-HWID/cpp)

add_executable(LicenseApp main.cpp)
target_link_libraries(LicenseApp PRIVATE SLHwid::slhwid)
target_compile_features(LicenseApp PRIVATE cxx_std_20)

Prepare an HWID before authorization. Commit it only after the response authorizes this device.

#include <slhwid/slhwid.hpp>

void authorizeCurrentDevice()
{
    auto session = slhwid::prepare({});
    if (!session) {
        showAccessError(session.error().message);
        return;
    }

    const auto response = authorizeWithYourService(session->hwid());
    if (!response.authorized) {
        showAccessError(response.message);
        return;
    }

    session->commit();
    grantAccess();
}

Visual Studio: C# / .NET

The .NET library targets .NET 8 and has no NuGet dependencies. Install the .NET desktop development workload in Visual Studio 2022.

1. Clone or download SL-HWID into your solution, for example at external/SL-HWID.
2. Open your solution in Visual Studio.
3. Right-click your application project, choose Add > Project Reference, choose Browse, and select external/SL-HWID/csharp/SLHwid/SLHwid.csproj.
4. Confirm that your application targets net8.0 or a compatible framework, then build the solution.

You can also add the reference directly to your project file:

<ItemGroup>
  <ProjectReference Include="..\external\SL-HWID\csharp\SLHwid\SLHwid.csproj" />
</ItemGroup>

using SLHwid;

async Task AuthorizeCurrentDeviceAsync()
{
    SLHwidSession session;
    try
    {
        session = SLHwid.Prepare(new SLHwidOptions());
    }
    catch (SLHwidDriftException)
    {
        ShowAccessError("This device needs to be reactivated.");
        return;
    }
    catch (SLHwidCorruptDataException)
    {
        ShowAccessError("This device needs to be reactivated.");
        return;
    }

    var response = await AuthorizeWithYourServiceAsync(session.Hwid);
    if (!response.Authorized)
    {
        ShowAccessError(response.Message);
        return;
    }

    session.Commit();
    GrantAccess();
}

Using SL-HWID with Bedrock

Bedrock clients for .NET, Go, Node.js, and Python use SL-HWID by default from version 1.0.0. In the Bedrock C++ client, set the hwid configuration value to an empty string to opt in. See the Bedrock reference for configuration and migration guidance. If you are moving an existing System Locker system to SL-HWID, reset existing HWID claims before customers update so the new identifier can be accepted.