Kairos Trusted Boot in Virtual Box

This section describes how to use Virtual Box to boot Kairos in “Trusted boot” mode

To install Kairos in “Trusted Boot Mode” the machine needs to meet the following requirements:

  • Must have a tpm v2.0 chip
  • Must be able to boot in EFI mode (not “legacy BIOS”)
  • Must have 1Gb of RAM or more
  • Must have 40Gb of disk or more

The following steps describe how to create a virtual machine suitable for Kairos trusted boot setup, using VirtualBox. As an example workload, LocalAI will be used.

Create an ISO

If you don’t already have an ISO to boot, you can create one using the following script:

#!/bin/bash

set -e

IMAGE="${IMAGE:-quay.io/kairos/ubuntu:24.04-core-amd64-generic-v3.2.3-uki}"
AURORABOOT_IMAGE="quay.io/kairos/auroraboot:latest"
OUTDIR=$PWD/build

cleanup() {
  # Run with docker to avoid sudo
  docker run --rm --entrypoint /bin/bash -v $PWD/build:/result $AURORABOOT_IMAGE -c 'rm -rf /result/*'
  rm -rf $OUTDIR
}

generateEfiKeys() {
  mkdir -p $OUTDIR/keys
  docker run --rm -v $OUTDIR/keys:/result $AURORABOOT_IMAGE genkey -e 7 --output /result KairosKeys
}

generateConfig() {
  mkdir -p $OUTDIR/config
  cat << EOF > "$OUTDIR/config/config.yaml"
#cloud-config

users:
  - name: kairos
    passwd: kairos
    groups:
      - admin

install:
  auto: true
  reboot: true

stages:
  initramfs:
    - files:
        - path: /etc/systemd/system/localai.service
          permissions: 0644
          content: |
            [Unit]
            Description=Local AI server
            After=network-online.target
            Wants=network-online.target

            [Service]
            Type=simple
            ExecStart=/usr/bin/localai --models-path="/usr/local/models"
            Restart=on-failure
            RestartSec=10

            [Install]
            WantedBy=multi-user.target
  boot:
    - name: "Starting localai"
      commands:
        - |
          systemctl enable localai.service
          systemctl start localai.service
EOF

}

buildBaseImage() {
  docker build -t kairos-localai - <<EOF
  FROM $IMAGE
  RUN curl -L -o localai https://github.com/mudler/LocalAI/releases/download/v2.22.1/local-ai-Linux-x86_64
  RUN chmod +x localai
  RUN mv localai /usr/bin/localai
EOF
}

buildISO() {
  docker run --rm \
    -v /var/run/docker.sock:/var/run/docker.sock \
    -v $OUTDIR:/result \
    -v $OUTDIR/keys/:/keys  \
    -v $OUTDIR/config/:/config \
    $AURORABOOT_IMAGE build-uki \
    --output-dir /result \
    --keys /keys \
    --output-type iso \
    --boot-branding "KairosAI" \
    --overlay-iso /config \
    --extend-cmdline "rd.immucore.debug rd.debug rd.shell" \
    oci://kairos-localai
}

fixPermissions() {
  docker run --privileged -e USERID=$(id -u) -e GROUPID=$(id -g) --entrypoint /usr/bin/sh -v $OUTDIR:/workdir --rm $AURORABOOT_IMAGE -c 'chown -R $USERID:$GROUPID /workdir'
}

moveISOFile() {
  mv build/kairos*.iso ./kairos.iso
}

echo "Cleaning up old artifacts" && cleanup
echo "Generating Config" && generateConfig
echo "Generating UEFI keys" && generateEfiKeys
echo "Building base image" && buildBaseImage
echo "Building ISO" && buildISO
echo "Fixing permissions" && fixPermissions
echo "Moving iso to current dir" && moveISOFile

If the script succeeds, you will find a .iso file inside $PWD/build and a keys directory with the UEFI keys used to sign the image.

Create a VM

#!/bin/bash

set -e

VM_NAME="KairosAI"
ISO_PATH=$PWD/kairos.iso
DISK_PATH=$PWD/Kairos.vdi

cleanup() {
    if VBoxManage list vms | grep -q "\"$VM_NAME\""; then
        echo "VM '$VM_NAME' found. Proceeding with cleanup."

        # Check if the VM is running
        if VBoxManage list runningvms | grep -q "\"$VM_NAME\""; then
            echo "VM '$VM_NAME' is running. Powering off..."
            VBoxManage controlvm "$VM_NAME" poweroff
            sleep 2  # Wait for a moment to ensure the VM powers off
        fi

        # Unregister and delete the VM and all associated files
        echo "Unregistering and deleting VM '$VM_NAME'..."
        VBoxManage unregistervm "$VM_NAME" --delete

        echo "Cleanup complete. VM '$VM_NAME' and associated files have been deleted."
    else
        echo "No VM named '$VM_NAME' found. No action needed."
    fi
}

createVM() {
    if [[ $(uname -m) == "x86_64" ]]; then
        ostype="Linux_64"
    else
        ostype="Linux_arm64"
    fi
    VBoxManage createvm --name "$VM_NAME" --ostype "$ostype" --register
    VBoxManage modifyvm "$VM_NAME" \
        --memory 10000 \
        --cpus 2 \
        --chipset piix3 \
        --firmware efi64 \
        --nictype1 82540EM \
        --nic1 nat \
        --natpf1 "guestssh,tcp,,2222,,22" \
        --natpf1 "localai,tcp,,8080,,8080" \
        --tpm-type "2.0" \
        --graphicscontroller vmsvga
        # These don't work of efi
        # https://www.virtualbox.org/ticket/19364
        #--boot1 disk \
        #--boot2 dvd

    VBoxManage createmedium disk --filename "$DISK_PATH" --size 40960
    VBoxManage storagectl "$VM_NAME" --name "SATA Controller" --add sata --controller IntelAhci
    VBoxManage storageattach "$VM_NAME" --storagectl "SATA Controller" --port 0 --device 0 --type hdd --medium "$DISK_PATH"

    # Add an IDE controller for CD-ROM and attach the ISO
    VBoxManage storagectl "$VM_NAME" --name "IDE Controller" --add ide
    VBoxManage storageattach "$VM_NAME" --storagectl "IDE Controller" --port 0 --device 0 --type dvddrive --medium "$ISO_PATH"

    # Hack to allow enrolling the PK key
    # Not sure why, but only this works. We allow it to boot once,
    # probably some default UEFI vars are written on the first boot which then
    # allow us to just enroll our PK key.
    # Also, it only works after adding disks and all (that's why it's here at the end).
    # Probably because it needs the cdrom to enroll some of the keys except the PK (?)
    VBoxManage startvm "$VM_NAME" --type=headless && sleep 3
    VBoxManage controlvm "$VM_NAME" poweroff && sleep 3
    VBoxManage modifynvram $VM_NAME enrollpk ‑‑platform‑key=$PWD/build/keys/PK.der ‑‑owner‑uuid=KairosKeys
}

usage() {
    echo "Usage: $0 {create|start|stop|cleanup}"
}

run() {
    # Check if a command was provided
    if [ -z "$1" ]; then
        usage
        exit 1
    fi

    # Determine which command to run based on the first argument
    case "$1" in
        create)
            createVM
            ;;
        start)
            VBoxManage startvm "$VM_NAME"
            ;;
        stop)
            VBoxManage controlvm "$VM_NAME" poweroff
            ;;
        cleanup)
            cleanup
            ;;
        *)
            echo "Invalid command: $1"
            usage
            exit 1
            ;;
    esac
}

run $@

Change boot order

Unfortunately, Virtual box doesn’t support changing boot order in efi mode (https://www.virtualbox.org/ticket/19364). This means, after installation, the order needs to change manually, in order to boot from the disk instead of the cdrom (iso).

Use localai web UI

Visit http://127.0.0.1:8080 from your browser to use LocalAI web UI