RAUC controls the update process on embedded Linux systems. It is both a target application that runs as an update client and a host/target tool that allows you to create, inspect and modify update files ("bundles").

Source Code: https://github.com/rauc/rauc

Documentation: https://rauc.readthedocs.org/

Chat: IRC channel #rauc on libera.chat (bridged to the Matrix channel #rauc:matrix.org)

• Fail-Safe & Atomic:
  • An update may be interrupted at any point without breaking the running system.
  • Update compatibility check
  • Atomic bootloader updates (eMMC boot partitions, MBR, GPT)
• Cryptographic signing and verification of updates using OpenSSL (signatures based on x.509 certificates)
  • Keys and certificates on PKCS#11 tokens (HSMs) are supported
• Flexible and customizable redundancy/storage setup
  • Symmetric setup (Root-FS A & B)
  • Asymmetric setup (recovery & normal)
  • Application partition, data partitions, ...
  • Allows grouping of multiple slots (rootfs, appfs) as update targets
• Built-in HTTP(S) streaming mode
  • No intermediate storage on target required
• Delta-like adaptive update support
  • Transparent selection of download optimization
• Alternative network delta-streaming mode (using casync tool)
  • chunk-based binary delta updates
  • special bundle format and external chunk store
• Bundle encryption for multiple recipients
• Bootloader support:
  • grub
  • barebox
  • u-boot
  • EFI
  • Custom implementation
• Storage support:
  • read-only filesystems: SquashFS, EROFS, dm-verity protected images, ...
  • read-write filesystems: ext4, VFAT, UBIFS, JFFS2
  • eMMC boot partitions (atomic update)
  • UBI volumes
  • raw NAND flash (using nandwrite)
  • raw NOR flash (using flashcp)
  • MBR partition table
  • GPT partition table
• Independent from update source
  • Simple webserver (e.g. lighttpd)
  • Software provisioning server (e.g. hawkBit with rauc-hawkbit-updater)
  • USB Stick
• Controllable via D-Bus interface
• Supports data migration
• Network protocol support using libcurl (https, http, ftp, ssh, ...)
• Several layers of update customization
  • Update-specific extensions (hooks)
  • System-specific extensions (handlers)
  • fully custom update script

• Create and sign update bundles
• Resign bundles
• Encrypt bundles
• Inspect bundle files

• Run as a system service (D-Bus interface)
• Install bundles
• View system status information
• Change status of symmetric/asymmetric/custom slots

• Boot state storage
  • GRUB: environment file on SD/eMMC/SSD/disk
  • Barebox: State partition on EEPROM/FRAM/MRAM or NAND flash
  • U-Boot: environment variable
  • EFI: EFI variables
  • Custom: depends on implementation
• Boot target selection support in the bootloader
• Enough mass storage for two symmetric/asymmetric/custom slots
• Storage location and storage space for the bundle:
  • For USB stick update: Sufficent space on the stick for (compressed) bundle, no on-target storage required
  • For HTTP(S) bundle streaming installation: Sufficient space on server, no on-target storage requied
    • For adaptive updates: some on-target storage for meta-data
  • For casync-based updates: temporary on-target storage for downloaded chunks required
  • For external (non-streaming) download: Sufficient temporary on-target storage space for (compressed) bundle
• Hardware watchdog (optional, but recommended)
• RTC (optional, but recommended)

Please see the documentation for details.

• build-essential
• meson
• libtool
• libdbus-1-dev
• libglib2.0-dev
• libcurl3-dev
• libssl-dev

sudo apt-get install build-essential meson libtool libdbus-1-dev libglib2.0-dev libcurl3-dev libssl-dev

For HTTP(S) streaming support, you also need netlink protocol headers:

sudo apt-get install libnl-genl-3-dev

If you intend to use json-support you also need

sudo apt-get install libjson-glib-dev

Required kernel options (either y or m):

• CONFIG_MD
• CONFIG_BLK_DEV_DM
• CONFIG_BLK_DEV_LOOP
• CONFIG_DM_VERITY
• CONFIG_SQUASHFS
• CONFIG_CRYPTO_SHA256
• CONFIG_BLK_DEV_NBD (for streaming support)
• CONFIG_DM_CRYPT (for encryption support)
• CONFIG_CRYPTO_AES (for encryption support)

For using tar archive in RAUC bundles with Busybox tar, you have to enable the following Busybox feature:

• CONFIG_FEATURE_TAR_AUTODETECT=y
• CONFIG_FEATURE_TAR_LONG_OPTIONS=y

Depending on the actual storage type and/or filesystem used, further target tools might be required. The documentation chapter Required Target Tools gives a more detailed list on these.

git clone https://github.com/rauc/rauc
cd rauc
meson setup build
meson compile -C build # or 'ninja -C build' on meson < 0.54.0

On the host system RAUC can be used directly from the build dir, or optionally be installed. On the target instead, installing is highly recommended as it also unpacks service and D-Bus configuration files required to run RAUC properly:

meson install

sudo apt-get install qemu-system-x86 time squashfs-tools
# Optional to run all tests:
# sudo apt-get install faketime casync grub-common openssl softhsm2 opensc opensc-pkcs11 libengine-pkcs11-openssl mtd-utils
./qemu-test

Create a directory with the content that should be installed:

mkdir content-dir/
cp $SOURCE/rootfs.ext4 content-dir/

Create a manifest describing which image to install where together with some meta info:

cat >> content-dir/manifest.raucm << EOF
[update]
compatible=FooCorp Super BarBazzer
version=2019.01-1
[image.rootfs]
filename=rootfs.ext4
EOF

Let RAUC create a bundle from this:

rauc --cert autobuilder.cert.pem --key autobuilder.key.pem bundle content-dir/ update-2019.01-1.raucb

Create a system configuration file in /etc/rauc/system.conf and start the service process in background:

rauc service &

To install the bundle (from local storage) on your target device, run:

rauc install update-2023.02-1.raucb

To install a bundle from a webserver (using RAUC's built-in HTTP(S) streaming), run:

rauc install https://example.com/update-2023.02-1.raucb

Fork the repository and send us a pull request.

Please read the Documentation's Contributing section for more details.

Copyright (C) 2015–2023 RAUC project

RAUC is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version.

This library 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 Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with this source code, see the file named COPYING. If not, see https://www.gnu.org/licenses/.