[][project]
# apparmor.d
[![][workflow]][action] [![][build]][project] [![][quality]][goreportcard]
**Full set of AppArmor profiles**
> **Warning**: This project is still in early development. Help is very welcome
> see [`CONTRIBUTING.md`](CONTRIBUTING.md)
## Description
A set of over 1400 AppArmor profiles which aims is to confine most of Linux base
applications and processes.
**Goals & Purpose**
- Support all distributions that support AppArmor:
* *Currenlty*: Archlinux, Debian 11 and the last Ubuntu LTS.
* Not (yet) tested on openSUSE
- Target both desktop and server,
- Confine all root processes. Eg: all systemd tools, bluetooth, dbus, polkit,
NetworkManager, OpenVPN, GDM, rtkit, colord...
- Confine all Desktop environments:
* *Currently only Gnome*, see `apparmor.d/groups/gnome`
- Confine all user services: Eg: Pipewire, Gvfsd, dbus, xdg, xwayland...
- Confine some "special" user applications: web browser, file browser...
- Should not break a normal usage of the confined software.
- Fully tested (Work in progress),
> This project is based on the excellent work from [Morfikov][upstream] and aims
to extend it to more Linux distributions and desktop environements.
## Concepts
There are over 50000 Linux packages and even more applications. It is simply not possible to write an AppArmor profile for all of them. Therefore a question arises: *What to confine and why?*
We take inspiration from the [Android/ChromeOS Security Model][android_model] and we apply it to the Linux world. Modern [linux security implementation][clipos] usually consider a core base image with a carefully set of selected applications. Everything else should be sandboxed. Therefore, this project tries to confine all the *core* applications you will usually find in a Linux system: all systemd services, xwayland, network, bluetooth, your desktop environment... Non-core user applications are out of scope as they should be sandboxed using a dedicated tool (minijail, bubblewrap...).
This is fundamentally different from how AppArmor is used on Linux server as it is common to only confine the applications that face the internet and/or the users.
## Installation
> **Warning**: In order to not break your system, the default package configuration install all profiles in complain mode. They can be enforced later. See [Enforce Mode](#enfore-mode)
**Requirements**
* An `apparmor` based linux distribution.
* Base profiles and abstractions shipped with AppArmor are supposed to be
installed.
* Go (build dependency only)
* rsync (build dependency only)
**Archlinux**
`apparmor.d-git` is available in the [Arch User Repository][aur]:
```sh
git clone https://aur.archlinux.org/apparmor.d-git.git
cd apparmor.d-git
makepkg -s
sudo pacman -U apparmor.d-*.pkg.tar.zst \
--overwrite etc/apparmor.d/tunables/global \
--overwrite etc/apparmor.d/tunables/xdg-user-dirs \
--overwrite etc/apparmor.d/abstractions/trash
```
> **Note**: The overwrite options are only required on the first install. You can use `yay` or your preferred AUR install method to update it.
The `PKGBUILD` included in this repository is intended for development only.
**Debian / Ubuntu**
Build using standard Debian package build tools:
```sh
sudo apt install apparmor-profiles build-essential config-package-dev debhelper golang-go rsync git
git clone https://github.com/roddhjav/apparmor.d.git
cd apparmor.d
dpkg-buildpackage -b -d --no-sign
sudo dpkg -i ../apparmor.d_*_all.deb
```
**Partial install**
For test purpose, you can install a specific profile with the following commands. The tool will also install required abstractions and tunables:
```
sudo ./pick
```
## Usage
**Enabled profiles**
Once installed and with the rules enabled, you can ensure the rules are loaded
with `sudo aa-satus`, it should give something like:
```
apparmor module is loaded.
1137 profiles are loaded.
794 profiles are in enforce mode.
...
343 profiles are in complain mode.
...
0 profiles are in kill mode.
0 profiles are in unconfined mode.
130 processes have profiles defined.
108 processes are in enforce mode.
...
22 processes are in complain mode.
...
0 processes are unconfined but have a profile defined.
0 processes are in mixed mode.
0 processes are in kill mode.
```
You can also list the current processes alongside with their security profile with
`ps auxZ`. Most of the process should then be confined.
**AppArmor Log**
The provided command `aa-log` allow you review AppArmor generated messages in a
colorful way:
```
$ aa-log
...
```
`aa-log` can optionally be given a profile name as argument to
only show the log for a given profile:
```
$ aa-log dnsmasq
DENIED dnsmasq open /proc/sys/kernel/osrelease comm=dnsmasq requested_mask=r denied_mask=r
DENIED dnsmasq open /proc/1/environ comm=dnsmasq requested_mask=r denied_mask=r
DENIED dnsmasq open /proc/cmdline comm=dnsmasq requested_mask=r denied_mask=r
```
## Personalisation
**AppArmor configuration**
As they are a lot of rules, it is recommended to enable caching AppArmor profiles.
In `/etc/apparmor/parser.conf`, uncomment `write-cache` and `Optimize=compress-fast`.
See [Speed up AppArmor Start] on the Arch Wiki for more information.
**Personal directories**
The profiles heavily use the XDG directory variables defined in `/etc/apparmor.d/tunables/xdg-user-dirs`. You can personalise these values with by creating a
file such as `/etc/apparmor.d/tunables/xdg-user-dirs.d/perso` with (for example)
the following content:
```sh
@{XDG_VIDEOS_DIR}+="Films"
@{XDG_MUSIC_DIR}+="Musique"
@{XDG_PICTURES_DIR}+="Images"
@{XDG_BOOKS_DIR}+="BD" "Comics"
@{XDG_PROJECTS_DIR}+="Git" "Papers"
```
**Local profiles**
You can extend a profile with your own rules by creating a file in the
`/etc/apparmor.d/local/` directory. For example, to extend the `gnome-shell`
profile, create a file `/etc/apparmor.d/local/gnome-shell` and add your rules.
Then, reload the apparmor rules with `sudo systemctl restart apparmor`.
## Enfore Mode
The default package configuration installs all profile in *complain* mode.
You can easily switch to *enforce* mode. To do this, edit `PKGBUILD` on Archlinux or `debian/rules` on Debian and remove the `--complain` option to the configure script. Then build the package as usual:
```diff
- ./configure --complain
+ ./configure
```
## Troubleshooting
**AppArmor messages**
Ensure that `auditd` is installed and running on your system in order to read
AppArmor log from `/var/log/audit/audit.log`. Then you can see the log with `aa-log`
**System Recovery**
Issue in some core profiles like the systemd suite, or the desktop environment
can fully break your system. This should not happen a lot, but if it does here
is the process to recover your system on Archlinux:
1. Boot from a Archlinux live USB
1. If you root partition is encryped, decrypt it: `cryptsetup open /dev/ vg0`
1. Mount your root partition: `mount /dev/ /mnt`
1. Chroot into your system: `arch-chroot /mnt`
1. Check the AppArmor messages to see what profile is faulty: `aa-log`
1. Temporarily fix the issue with either:
- When only one profile is faultly, remove it: `rm /etc/apparmor.d/`
- Otherwise, you can also remove the package: `pacman -R apparmor.d`
- Alternativelly, you may temporarily disable apparmor as it will allow you to
boot and studdy the log: `systemctl disable apparmor`
1. Exit, umount, and reboot:
```sh
exit
umount -R /mnt
reboot
```
1. Create an issue and report the output of `aa-log`
## Tests
A full test suite to ensure compatibility across distributions and softwares is still a work in progress.
Here is an overview of the current CI jobs:
**On Gitlab CI**
- Package build for all supported distribution
- Profiles preprocessing verification for all supported distribution
- Go based command linting and unit tests
**On Github Action**
- Integration test on the ubuntu-latest VM: run a simple list of tasks with
all the rules enabled and ensure no new issue has been raised. Github Action
is used as it offers a direct access to a VM with AppArmor included.
## Contribution
Feedbacks, contributors, pull requests are all very welcome. Please read the
[`CONTRIBUTING.md`](CONTRIBUTING.md) file for more details on the contribution process.
## License
This program is based on Mikhail Morfikov's [apparmor profiles project][upstream] and thus has the same license (GPL2).
```
Copyright (C) Alexandre PUJOL & Mikhail Morfikov
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; version 2 of the License.
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, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
```
[upstream]: https://gitlab.com/morfikov/apparmemall
[project]: https://gitlab.com/roddhjav/apparmor.d
[build]: https://gitlab.com/roddhjav/apparmor.d/badges/master/pipeline.svg?style=flat-square
[workflow]: https://img.shields.io/endpoint.svg?url=https%3A%2F%2Factions-badge.atrox.dev%2Froddhjav%2Fapparmor.d%2Fbadge&style=flat-square
[action]: https://actions-badge.atrox.dev/roddhjav/apparmor.d/goto
[quality]: https://img.shields.io/badge/go%20report-A+-brightgreen.svg?style=flat-square
[goreportcard]: https://goreportcard.com/report/github.com/roddhjav/apparmor.d
[aur]: https://aur.archlinux.org/packages/apparmor.d-git
[android_model]: https://arxiv.org/pdf/1904.05572
[clipos]: https://clip-os.org/en/
[Speed up AppArmor Start]: https://wiki.archlinux.org/title/AppArmor#Speed-up_AppArmor_start_by_caching_profiles
[write xor execute]: https://en.wikipedia.org/wiki/W%5EX