Firejail

Firejail is a SUID sandbox program that reduces the risk of security breaches by restricting the running environment of untrusted applications using Linux namespaces, seccomp-bpf and Linux capabilities. It allows a process and all its descendants to have their own private view of the globally shared kernel resources, such as the network stack, process table, mount table. Firejail can work in a SELinux or AppArmor environment, and it is integrated with Linux Control Groups.

Written in C with virtually no dependencies, the software runs on any Linux computer with a 3.x kernel version or newer. It can sandbox any type of processes: servers, graphical applications, and even user login sessions. The software includes sandbox profiles for a number of more common Linux programs, such as Mozilla Firefox, Chromium, VLC, Transmission etc.

The sandbox is lightweight, the overhead is low. There are no complicated configuration files to edit, no socket connections open, no daemons running in the background. All security features are implemented directly in Linux kernel and available on any Linux computer. To start the sandbox, prefix your command with “firejail”:

$ firejail firefox            # starting Mozilla Firefox
$ firejail transmission-gtk   # starting Transmission BitTorrent 
$ firejail vlc                # starting VideoLAN Client
$ sudo firejail "/etc/init.d/nginx start && sleep inf"

Project webpage: https://l3net.wordpress.com/projects/firejail/

Download and Installation: https://l3net.wordpress.com/projects/firejail/firejail-download-and-install/

Features: https://l3net.wordpress.com/projects/firejail/firejail-features/

Usage: https://l3net.wordpress.com/projects/firejail/firejail-usage/

FAQ: https://l3net.wordpress.com/projects/firejail/firejail-faq/

Development version 0.9.35

Firefox whitelists:

The current whitelist of files and directories for Firefox is as follows:

whitelist ~/.mozilla (0.9.34)
whitelist ~/Downloads (0.9.34)
whitelist ~/Загрузки (new in 0.9.35)
whitelist ~/dwhelper (0.9.34)
whitelist ~/.cache/mozilla/firefox (new in 0.9.35)
whitelist ~/.zotero (0.9.34)
whitelist ~/.lastpass (0.9.34)
whitelist ~/.vimperatorrc (0.9.34)
whitelist ~/.vimperator (0.9.34)
whitelist ~/.pentadactylrc (0.9.34)
whitelist ~/.pentadactyl (0.9.34)
whitelist ~/.config/gnome-mplayer (new in 0.9.35)
whitelist ~/.cache/gnome-mplayer/plugin (new in 0.9.35)
include /etc/firejail/whitelist-common.inc

/etc/firejail/whitelist-common.inc

whitelist ~/.config/mimeapps.list (new in 0.9.35)
whitelist ~/.icons (new in 0.9.35)

# fonts
whitelist ~/.fonts (0.9.34)
whitelist ~/.fonts.d (0.9.34)
whitelist ~/.fontconfig (0.9.34)
whitelist ~/.fonts.conf (0.9.34)
whitelist ~/.fonts.conf.d (0.9.34)

# gtk
whitelist ~/.gtkrc (new in 0.9.35)
whitelist ~/.gtkrc-2.0 (0.9.34)
whitelist ~/.config/gtk-3.0 (new in 0.9.35)
whitelist ~/.themes (new in 0.9.35)

If you are using a plugin or extension that requires other directories, please open a new issue: https://github.com/netblue30/firejail/issues

New security profiles:

New profiles introduced in this version: unbound, dnscrypt-proxy

--noblacklist

      --noblacklist=dirname_or_filename
              Disable blacklist for this directory or file.

              Example:
              $ firejail
              $ nc dict.org 2628
              bash: /bin/nc: Permission denied
              $ exit

              $ firejail --noblacklist=/bin/nc
              $ nc dict.org 2628
              220 pan.alephnull.com dictd 1.12.1/rf on Linux 3.14-1-amd64

--whitelist

Whitelist command accepts files in user home, /dev, /media, /var, and /tmp directories.

--tracelog

Tracelog command enables auditing blacklisted files and directories. A message is sent to syslog in case the file or the directory is accessed. Example:

$ firejail --tracelog firefox

Syslog example:

$ sudo tail -f /var/log/syslog
[...]
Dec  3 11:43:25 debian firejail[70]: blacklist violation - sandbox 26370, exe firefox,
   syscall open64, path /etc/shadow
Dec  3 11:46:17 debian firejail[70]: blacklist violation - sandbox 26370, exe firefox,
   syscall opendir, path /boot
[...]

Tracelog is enabled by default in several profile files.

--profile-path

For various reasons some users might want to keep the profile files in a different directory. Using --profile-path command line option, Firejail can be instructed to look for profiles into this directory.

This is an example of relocating the profile files into a new directory, /home/netblue/myprofiles. Start by creating the new directory and copy all the profile files in:

$ mkdir ~/myprofiles && cd ~/myprofiles && cp /etc/firejail/* .

Using sed utility, modify the absolute paths for include commands:

$ sed -i "s/\/etc\/firejail/\/home\/netblue\/myprofiles/g" *.profile
$ sed -i "s/\/etc\/firejail/\/home\/netblue\/myprofiles/g" *.inc

Start Firejail using the new path:

$ firejail --profile-path=~/myprofiles