I have .NET Framework 4.7.2 library to store and retrieve sensitive data (like tokens) with help of CredentialManagement package on Windows. Now I need to make this library work both on Windows and Linux. I’ve retargeted it to .NET Standard 2.0 (to be able to consume it from both .NET Framework and .NET Core) and used KdSoft.CredentialManagement package (since CredentialManagement.Standard package was unlisted from nuget.org). I determine operating system with RuntimeInformation.IsOSPlatform like that:

if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
{
    //Use CredentialManager
}
else if (RuntimeInformation.IsOSPlatform(OSPlatform.Linux))
{
    //What to use here?
}
else if (RuntimeInformation.IsOSPlatform(OSPlatform.OSX))
{
    throw new NotImplementedException();
}

But I have no idea what library to use on Linux to achieve the same goal. What is the most common approach on that OS?

P. S. My library doesn’t use any database. And I saw similar questions #1 and #2: they are about the Windows-only approach and answers there (Data Protection API for Windows – ProtectData class) doesn`t support Windows Home and on non-NTFS.