Software license registration file issuance and control

Question

I have a system to control and issue electronic license registration files, so I have control of how many machines my software can run. My teacher advised me to use the CPUID processor to validate and generate a license file (get the CPUID and make a calculation on top of it, so the result would be unique to each processor) and the validation would be made at the time of installation, the requests would be made to the server that would request the CPUID from the machine and return the license file.

Are there other ways to do this license registration control? Is there an API or feature? And how can the implementation be done?

Here follows my basic prototype that gets the CPUID and performs a calculation. There are two functions string getCPUID() and double CalculaCpuId(string cpuid) is the basis for generating the electronic license record file.

Function getCPUID:

private string getCPUID()
{
    String cpuid = "";
    try
    {
        ManagementObjectSearcher mbs = new ManagementObjectSearcher("Select ProcessorID From Win32_processor");
        ManagementObjectCollection mbsList = mbs.Get();

        foreach (ManagementObject mo in mbsList)
        {
            cpuid = mo["ProcessorID"].ToString();
        }

        return cpuid;
    }
    catch (Exception) { return cpuid; }
}

Function CalculaCpuId:

private double CalculaCpuId(string cpuid) 
{
    if (string.IsNullOrEmpty(cpuid))
        return 0;

    double resultado = 0;
    int soma = 0;
    string digito;

    for (int i = 0; i < cpuid.Length; i++)
    {
        digito = cpuid[i].ToString();
        soma += Convert.ToInt32(digito, 16);
    }

    resultado = (soma / ((Math.Pow(2, 2)) + 4));

    return resultado;
}

I am using Visual Studio to develop my system that needs license registration control.

Answer 1

Taking the processor ID is not a solution, this information may not even be available. And this was not even done to identify which is the individual processor. Any solution trying to identify the machine has potential to fail.

One that they use and usually works better in some situations is take the serial number of the disk. It is far from being a perfect solution, on the contrary, it has its own flaws. I don’t like WMI much but if you want to continue using search for DeviceID.

There are ready-made software that can do this for you.