Package: depthcharge-tools
This project is a collection of tools that ease and automate interacting
withdepthcharge, the Chrome OS bootloader.Depthcharge is built into the firmware of Chrome OS boards, uses a
custom verified boot flow and usually cannot boot other operating
systems as is. This means someone who wants to use e.g.Debianon these
boards need to either replace the firmware or work their system intothe format depthcharge expects. These tools are about the latter.Right now these are developed on and tested with only a few boards,
but everything will attempt to work on other boards based on my best
guesses.mkdepthchargeThemkdepthchargetool is intended to wrapmkimageandvbutil_kernelto provide reasonable defaults to them, hide their idiosyncrasies and
automate creating a depthcharge-bootable partition image appropriate for
the running architecture. An example invocation on a Samsung Chromebook
Plus (v1, arm64) could be:$ mkdepthcharge -o depthcharge.img --compress lzma \
    --cmdline "console=tty1 root=/dev/mmcblk0p2 rootwait" -- \
    /boot/vmlinuz.gz /boot/initrd.img rk3399-gru-kevin.dtbHere, mkdepthcharge would automatically extract and recompress the
kernel, create a FIT image, put command line parameters into a file,
create an empty bootloader, and provide defaults for vboot keys and
other arguments while building the partition image.depthchargectlThedepthchargectltool goes a step further and aims to fully automate
bootable image creation and Chrome OS kernel partition management, even
the board-specific and distro-specific parts. With proper integration
with your distribution, depthchargectl can keep your system bootable
across kernel and initramfs changes without any interaction on your
part. Even without such integration, a single command automates most of
the work:# Use --allow-current if you only have one Chrome OS kernel partition.
$ sudo depthchargectl write --allow-current
Building depthcharge image for board 'Samsung Chromebook Plus' ('kevin').
Built depthcharge image for kernel version '5.10.0-6-arm64'.
Wrote image '/boot/depthcharge/5.10.0-6-arm64.img' to partition '/dev/mmcblk1p1'.
Set partition '/dev/mmcblk1p1' as next to boot.

# After a reboot, you or an init service should run this.
$ sudo depthchargectl bless
Set partition '/dev/mmcblk1p1' as successfully booted.InstallationThis depends on thepkg_resourcesPython package which is usually
distributed withsetuptools. The tools can run a number of programs
when necessary, which should be considered dependencies:futility(vbutil_kernel),cgpt,crossystemmkimage,fdtget,fdtputlz4,lzmagzip,lzop,bzip2,xz,zstd(optional, for unpacking compressed/boot/vmlinuz)Therst2manprogram (fromdocutils) should be used to convert
themkdepthcharge.rstanddepthchargectl.rstfiles to manual
pages. However, this is not automated here and has to be done manually.This project (or at leastdepthchargectl) is meant to be integrated
into your operating system by its maintainers, and the best way to
install it is through your OS’ package manager whenever possible.DebianAn officialdepthcharge-tools Debian packageis available upstream,
since Debian 12 (bookworm). You can install it like any other package:$ sudo apt install depthcharge-toolsIt includes the necessary system hooks and services to make and keep
your Chromebook bootable, enabled by default. These however do not
trigger on the depthcharge-tools installation, but on kernel and
initramfs changes. To trigger these hooks manually, run:$ sudo update-initramfs -uAlpine LinuxThanks to the efforts in supportingpostmarketOS on ChromeOS Devices,
there is an officialdepthcharge-tools package for Alpine Linux. You
should be able to install it as:$ sudo apk add depthcharge-toolsHowever, this doesn’t include any system hooks or services to keep your
Chromebook bootable.PipPython binary wheels are uploaded toPyPI, and it should be possible to
install the python package usingpip. However, this does not install
the manual pages, bash/zsh completions, systemd/init.d service files,
and OS-specific kernel/initramfs hooks.You can install in–usermode, but this makes it quite hard to usedepthchargectlas root. As root privileges are necessary to manipulate
system block devices this limits you a bit:$ pip install --user depthcharge-toolsAlthough inadvisable, you can install as root to overcome that caveat.
Alternatively, see thePYTHONPATHhack in one of the later sections.ConfigurationYou can configure depthcharge-tools with the/etc/depthcharge-tools/configfile, or by
putting similar fragments in the/etc/depthcharge-tools/config.ddirectory. See theconfig.inifile for the built-in default configuration.Settings in the[depthcharge-tools]section are the global defaults
from which all commands inherit. Other than that, config sections have
inheritence based on their names i.e. those in the form of[a/b/c]inherit from[a/b]which also inherits from[a]. Each subcommand
reads its config from such a subsection.Currently the following configuration options are available:[depthcharge-tools]
enable-system-hooks: Write/remove images on kernel/initramfs changes
vboot-keyblock: The kernel keyblock file for verifying and signing images
vboot-private-key: The private key (.vbprivk) for signing images
vboot-public-key: The public key for (.vbpubk) verifying images

[depthchargectl]
board: Codename of a board to build and check images for
ignore-initramfs: Do not include an initramfs in the image
images-dir: Directory to store built images
kernel-cmdline: Kernel commandline parameters to use
zimage-initramfs-hack = How to support initramfs on x86 boardsFor longer explanations check the manual pages of each command for
options named the same as these.Installation for developmentIf you want to use development versions, you can clone this repository
and install using pip:$ pip3 install --user -e /path/to/depthcharge-toolsHopefully, you should be able to use depthchargectl with just that:$ depthchargectl build --output depthcharge.img
Building depthcharge image for board 'Samsung Chromebook Plus' ('kevin').
Built depthcharge image for kernel version '5.10.0-6-arm64'.
depthchargectl.imgMostdepthchargectlfunctionality needs root as it handles disks and
partitions, and you need special care while invoking as root:$ depthchargectl() {
    sudo PYTHONPATH=/path/to/depthcharge-tools \
        python3 -m depthcharge_tools.depthchargectl "$@"
}

$ depthchargectl list /dev/mmcblk0
S  P  T  PATH
1  2  0  /dev/mmcblk0p2
1  1  0  /dev/mmcblk0p4
0  0  15 /dev/mmcblk0p6Or you can add a similar invocation to the /usr/local/bin files, so that
it’s available to both normal users and root:$ sudo tee /usr/local/bin/depthchargectl <<EOF
#!/bin/sh
export PYTHONDONTWRITEBYTECODE=1
export PYTHONPATH=/path/to/depthcharge-tools
exec python3 -m depthcharge_tools.depthchargectl "\$@"
EOF

$ sudo chmod +x /usr/local/bin/depthchargectlLicenseCopyright (C) 2019-2023 Alper Nebi Yasak <alpernebiyasak@gmail.com>This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.You should have received a copy of the GNU General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>See COPYRIGHT and LICENSE files for full copyright information.