FedoraBook

Let's put all the fancy features together, we developed in the last years:

• Combined kernel+initramfs EFI binaries
• Secure Boot
• clevis with TPM2
• LUKS2
• dm-verity + squashfs root
• Flatpak
• flickerless boot

and build a Chromebook like Fedorabook, where you can install all software via Flatpak.

This is WIP. Please test and report issues, comments or missing components on https://pagure.io/Fedorabook/issues

Goals

• secure boot to the login screen
• immutable /usr and maybe /etc
• ensured integrity to the login screen
• encrypted volatile data
• A/B boot switching for updates
• Flatpak
• basic desktop
• optional: bind encrypted data partition to TPM2
• optional: frequent reencryption of the data partition

Non-Goals

• can't secure against someone writing anything to disk
• can't secure against someone scraping secret keys from the kernel

TODO

• merge mkimage.sh and clonedisk
• change partition UUIDs for /data
  • UUID for TPM LUKS
  • UUID for LUKS
  • UUID for unencrypted xfs
• ensure /data to be on same disk as root
• add "load=" to kernel command line via efi stub
• update mechanism
• add proper EFI boot manager entries for A and B
• extend efi stub for recovery boot in the old image
• signing tools
• firmware update
• selinux?

Complete / What works already?

• boot from single efi binary
• dm_verity + squashfs immutable, integrity checked root
• passwd + shadow + group + gshadow decoupled from system in /var
• bind LUKS2 with tpm2 to machine
• /home and /var on single data partition

Known Failures

• gnome-software: can't update firmware repo
• systemd: failed to umount /var

Create

$ sudo ./prepare-root.sh \
  --releasever 29 \
  --pkglist pkglist.txt \
  --excludelist excludelist.txt \
  --logo logo.bmp --name FEDORABOOK \
  --outdir <IMGDIR>

or download a prebuilt image, unpack and use this as <IMGDIR>.

QEMU disk image

$ sudo ./mkimage.sh <IMGDIR> image.raw 

USB stick

$ sudo ./mkimage.sh <IMGDIR> /dev/disk/by-path/pci-…-usb…

Install from USB stick

• Enter BIOS
  • turn on UEFI boot
  • turn on TPM2
• Enter BIOS boot menu
• Select USB stick
• Login (user: admin, pw: admin)
• Start gnome-terminal
• sudo
• clonedisk <usb stick device> <harddisk device>
• reboot
• remove stick

Post Boot

Persistent journal

$ sudo mkdir /var/log/journal