Bavarce.LicenseClient 1.0.4

LicenseClient (.NET)

A small, cross-platform .NET class library (DLL) to manage software licensing for desktop applications:

• Generate deterministic device HWID
• Activate / Deactivate license on server
• Check license status
• Local secure storage for offline scenarios, including last server validation time
• Supports multiple products via ProductCode

Target: .NET 6+, .NET Standard 2.0, .NET Framework 4.8. Works in WinForms / WPF / Console / Services.

Features

• GetHWID() — deterministic hardware fingerprint (MAC + hostname, CPU + motherboard on .NET Framework).
• ActivateLicenseAsync(string licenseKey, string productCode) — register device on server and store locally.
• DeactivateLicenseAsync(string productCode) — release device and clear local storage.
• CheckLicenseAsync(string productCode) — verify license & device status with server. Updates local storage with last server time.
• ValidateOffline(string productCode, int maxOfflineHours = 72) — offline validation using last server timestamp. Detects system clock tampering.
• Local encrypted storage of license info (license.dat) under %LOCALAPPDATA%\Bavarce\<ProductCode>.

Usage Example

using Bavarce.LicenseClient;

var productCode = "ETABS_PLUGIN";
var apiUrl = "https://your-company-api";
var lm = new LicenseManager(apiUrl);

// Activate license
var result = await lm.ActivateLicenseAsync("LICENSE-KEY-1234", productCode);
if(result.status == "ok")
{
    Console.WriteLine("License activated!");
}

// Check license online
var check = await lm.CheckLicenseAsync(productCode);
if(check.status == "ok")
{
    Console.WriteLine("License valid (online).");
}

// Validate offline
if(lm.ValidateOffline(productCode))
{
    Console.WriteLine("License valid (offline).");
}

// Deactivate license
var deactivate = await lm.DeactivateLicenseAsync(productCode);
if(deactivate.status == "ok")
{
    Console.WriteLine("License deactivated.");
}

Notes

• Supports multiple products by specifying productCode.
• Offline validation uses last successful server timestamp to prevent system clock tampering.
• License info is stored securely and encrypted using DPAPI (.NET Framework) or AES (cross-platform).
• Always call DeactivateLicenseAsync before moving a license to another machine.

Installation

Install from NuGet:

dotnet add package Bavarce.LicenseClient