Protect a Qt C++ Cross Platform Application

Requirements: QLM Enterprise v15+

Following is a step-by-step procedure to protect a Qt C++ Cross-Platform app. Note that the steps below assume you have a QLM License Server already set up.

1. Launch the QLM Management Console

2. Create a product from the “Define Product” tab or use the Demo 1.0 product if you are evaluating QLM. 

3. Go to the "Protect your application tab":

• Page 1: Select the product to protect and the License Server then click Next
• Page 2: Select "Other Languages"
• Page 2: Select "Qt C++ Cross Platform"
• Page 3: Leave the default settings
• Page 4: Select the folder where your want to generate the Qt C++ source code and click Save
• Page 5: Click Finish

4. Add the generated files to your project.

5. If you are building on Windows using ming, you may need to execute the ming tool windeployqt.exe as follows: windeployqt.exe <name of your executable>

6. Install OpenSSL

• 64 bit Open SSL binaries
• 32 bit Open SSL binaries

7. Copy the required binaries to your bin folder. On Windows, you will need:

• libcrypto-1_1-x64.dll
• libgcc_s_seh-1.dll
• libssl-1_1-x64
• libstdc++-6.dll
• libwinpthread-1.dll
• Qt6Core.dll
• Qt6Gui.dll
• Qt6Network.dll
• Qt6Widgets.dll
• Qt6Xml.dll

7. Review the provided Qt sample to determine how to validate a license at startup. The sample is located in: %Public%\Public Documents\Quick License Manager\Samples\qlmenterprise\Qt

The parameters that may need to be updated in the sample are in mainwindow.cpp:

• licenseFile: location where the license file will be created
• URL: URL to the QLM License Server
• productID: Your product's Product ID as per the Define Products/Product Information tab
• majorVersion: Your product's Major Version as per the Define Products/Product Information tab
• minorVersion: Your product's Minor Version as per the Define Products/Product Information tab
• publicKey: Your product's RSA Public Key as per the Define Products / Encryption Keys tab

In your application, at startup, you must:

• Create an instance of the QlmLicense class:

  license = new QlmLicense();    

• Load the license file if it exists:

  license->loadLicense(licenseFile,publicKey,computerId);

• To activate a license, create a function called ValidateLicenseOnServer and call it:

  bool MainWindow::ValidateLicenseOnServer ()
  {
      if (license->Ping (url))
      {
          QString ak = license->getActivationKey();
          QString ck = license->getComputerKey();
          QString cid = license->getComputerID();
  
          license->activateLicense(url, ak, ck, cid, productID, majorVersion, minorVersion);
  
          if (license->isLicenseValid(computerId) == false)
          {
              return false;
           }
        }
        return true;
  }

To generate a license key for testing purposes:

• Go to the Manage Keys tab.
• Click "Create Activation Key"
• Select the Product (Demo 1.0 for trials) and click Ok.
• Copy and Paste the generated Activation Key in the License Wizard launched when your application starts up and follow the steps in the wizard.