Creating Application VM

Application VM (App VM) is a VM that improves trust in system components by isolating applications from the host OS and other applications. Virtualization with hardware-backed mechanisms provides better resource protection than traditional OS. This lets users use applications of different trust levels within the same system without compromising system security. While the VMs have overhead, it is acceptable as a result of improved security and usability that makes the application seem like it is running inside an ordinary OS.

As a result, both highly trusted applications and untrusted applications can be hosted in the same secure system when the concerns are separated in their own App VM.

To create an App VM, do the following:

1. Create the new configuration file for your VM in the modules/reference/appvms directory.
   You can use an already existing VM file as a reference, for example: modules/reference/appvms/business.nix.

   Each VM has the following properties:

   Property	Type	Unique	Description	Example
   name	str	yes	This name is postfixed with -vm and will be shown in microvm list. The name, for example, chromium-vm will be also the VM hostname. The length of the name must be 8 characters or less.	“chromium”
   packages	list of types.package	no	Packages to include in a VM. It is possible to make it empty or add several packages.	[chromium top]
   macAddress	str	yes	Needed for network configuration.	"02:00:00:03:03:05"
   ramMb	int, [1, …, host memory]	no	Memory in MB.	3072
   cores	int, [1, …, host cores]	no	Virtual CPU cores.

2. Create a new option for your VM in modules/reference/appvms/default.nix. For example:

    business-vm = lib.mkEnableOption "Enable the Business appvm";
    new-vm = lib.mkEnableOption "Enable the New appvm"; # your new vm here

        ++ (lib.optionals cfg.business-vm [(import ./business.nix {inherit pkgs lib config;})])
        ++ (lib.optionals cfg.new-vm [(import ./new_vm_name.nix {inherit pkgs lib config;})]); # your new vm here

3. Add your new VM to the profile file, for example mvp-user-trial.nix:

          business-vm = true;
          new-vm = true; # your new vm here

4. Add an IP and the VM name in modules/common/networking/hosts.nix. For example:

    {
      ip = 105;
      name = "business-vm";
    }

5. Add an application launcher in modules/common/services/desktop.nix.

   A launcher element has the following properties:

   • name: the name of the launcher;
   • path: path to the executable you want to run, like a graphical application;
   • icon: path to an icon to show. If you have an icon package for your launcher, add it here as well: packages/icon-pack/default.nix.