Microkernel Service Maker (MSM)

Currently broken.

Prerequisites

This has only been tested on an M2 Air running OSX 13.4.

How it Works

The idea is simple. Create a base Linux image that's super small (http://tinycorelinux.net/). Then add your desired service to it and boot it.

The following details the underpinnings of the "Microkernel Service Maker" (MSM) CLI.

Creating the Base Image

The base disk-image is what will be used to generate all future service disk-images.

First make an empty disk image (taking into account how much disk space you will need).

qemu-img create -f raw ./images/base.img 50M

Now boot your base Linux iso image into the empty disk image. As of writing Core was the kernel used in this example. Everything following is specific to this distribution.

qemu-system-x86_64 -m 512 -hda ./images/base.img -cdrom ./iso/core-x86-14.0.iso -boot d

Once the VM loads the boot screen, hit return. No boot options are required at this point.

Now type the following to install the install tool.

tce-load -wil tc-install

When the downloads have completed, execute the tool via sudo.

sudo tc-install.sh

Then enter the following answers to the options when asked.

c (from booted CDROM)
f (frugal)
1 (whole Disk)
2 (sda)
y (install boot loader)
return (skip, not required)
3 (ext4)
opt=sda1 waitusb=0 noautologin
y (yes)

Now poweroff the VM to commit the settings.

sudo poweroff

With that done, boot up the base-image VM with the following command.

qemu-system-x86_64 -m 512 -hda ./images/base.img

Then poweroff again. This creates the /opt/ directory used later to load services.

sudo poweroff

Creating a Service Disk Image

This process uses the disk-image built above as the base for any services created.

Create a new empty disk image.

qemu-img create -f raw "./pkg/service.img" 50M

Attach the empty image.

hdiutil attach -imagekey diskimage-class=CRawDiskImage -nomount ./pkg/service.img

Copy the base-image into the new empty disk image image.

dd if="../../new/images/base.img" of="/dev/disk4"

Eject the new disk image.

hdiutil eject /dev/disk4

Adding a Service to the Disk Image

Core has a simple system for running a shell script after boot. All this step does is copy the service executable(s) and a shell script to start said service.

hdiutil attach ./pkg/service.img -mountpoint ./mnt

cp -r ./srv ./mnt/opt/msm/
echo "/opt/msm/start.sh" >> "./mnt/opt/bootlocal.sh"

hdiutil eject ./mnt

Running the Service Image

The Microkernel Service is now ready to perform it's duties.

To run the service in a VM (with network bridging) use the following command.

qemu-system-x86_64 -m 512 -hda ./pkg/service.img -nic vmnet-bridged,ifname=en0

Once running you can use ifconfig to discover the VM's IP address.

ricallinson / msm