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
Project webpage: https://firejail.wordpress.com/
Download and Installation: https://firejail.wordpress.com/download-2/
Features: https://firejail.wordpress.com/features-3/
Documentation: https://firejail.wordpress.com/documentation-2/
FAQ: https://firejail.wordpress.com/support/frequently-asked-questions/
This is a small thing, but very convenient. Make a symbolic link (ln -s) to /usr/bin/firejail under the name of the program you want to run, and put the link in the first $PATH position (for example in /usr/local/bin). Example:
$ which -a transmission-gtk
/usr/bin/transmission-gtk
$ sudo ln -s /usr/bin/firejail /usr/local/bin/transmission-gtk
$ which -a transmission-gtk
/usr/local/bin/transmission-gtk
/usr/bin/transmission-gtk
We have in this moment two entries in $PATH for transmission. The first one is a symlink to firejail. The second one is the real program. Starting transmission in this moment, invokes "firejail transmission-gtk"
$ transmission-gtk
Redirecting symlink to /usr/bin/transmission-gtk
Reading profile /etc/firejail/transmission-gtk.profile
Reading profile /etc/firejail/disable-mgmt.inc
Reading profile /etc/firejail/disable-secret.inc
Reading profile /etc/firejail/disable-common.inc
Reading profile /etc/firejail/disable-devel.inc
Parent pid 19343, child pid 19344
Blacklist violations are logged to syslog
Child process initialized
--ip6=address
Assign IPv6 addresses to the last network interface defined by a
--net option.
Example:
$ firejail --net=eth0 --ip6=2001:0db8:0:f101::1/64 firefox
--netfilter6=filename
Enable the IPv6 network filter specified by filename in the new
network namespace. The filter file format is the format of
ip6tables-save and ip6table-restore commands. New network
namespaces are created using --net option. If a new network
namespaces is not created, --netfilter6 option does nothing.
--join-filesystem=name
Join the mount namespace of the sandbox identified by name. By
default a /bin/bash shell is started after joining the sandbox.
If a program is specified, the program is run in the sandbox.
This command is available only to root user. Security filters,
cgroups and cpus configurations are not applied to the process
joining the sandbox.
--join-filesystem=pid
Join the mount namespace of the sandbox identified by process
ID. By default a /bin/bash shell is started after joining the
sandbox. If a program is specified, the program is run in the
sandbox. This command is available only to root user. Security
filters, cgroups and cpus configurations are not applied to the
process joining the sandbox.
--join-network=name
Join the network namespace of the sandbox identified by name. By
default a /bin/bash shell is started after joining the sandbox.
If a program is specified, the program is run in the sandbox.
This command is available only to root user. Security filters,
cgroups and cpus configurations are not applied to the process
joining the sandbox.
--join-network=pid
Join the network namespace of the sandbox identified by process
ID. By default a /bin/bash shell is started after joining the
sandbox. If a program is specified, the program is run in the
sandbox. This command is available only to root user. Security
filters, cgroups and cpus configurations are not applied to the
process joining the sandbox.