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.

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/

Travis-CI status: https://travis-ci.org/netblue30/firejail

Compile and install

$ git clone https://github.com/netblue30/firejail.git
$ cd firejail
$ ./configure && make && sudo make install-strip

On Debian/Ubuntu you will need to install git and a compiler:

$ sudo apt-get install git build-essential

Running the sandbox

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

Run "firejail --list" in a terminal to list all active sandboxes. Example:

$ firejail --list
1617:netblue:/usr/bin/firejail /usr/bin/firefox-esr
7719:netblue:/usr/bin/firejail /usr/bin/transmission-qt
7779:netblue:/usr/bin/firejail /usr/bin/galculator
7874:netblue:/usr/bin/firejail /usr/bin/vlc --started-from-file file:///home/netblue/firejail-whitelist.mp4
7916:netblue:firejail --list

Desktop integration

Integrate your sandbox into your desktop by running the following two commands:

$ firecfg --fix-sound
$ sudo firecfg

The first command solves some shared memory/PID namespace bugs in PulseAudio software prior to version 9. The second command integrates Firejail into your desktop. You would need to logout and login back to apply PulseAudio changes.

Start your programs the way you are used to: desktop manager menus, file manager, desktop launchers. The integration applies to any program supported by default by Firejail. There are about 250 default applications in current Firejail version, and the number goes up with every new release. We keep the application list in /usr/lib/firejail/firecfg.config file.

Security profiles

Most Firejail command line options can be passed to the sandbox using profile files. You can find the profiles for all supported applications in /etc/firejail directory.

If you keep additional Firejail security profiles in a public repository, please give us a link:

• https://github.com/chiraag-nataraj/firejail-profiles

• https://github.com/triceratops1/fe

Use this issue to request new profiles: #1139

Current development version: 0.9.51

Whitelisting, globbing etc.

We deployed a whitelist for /var directory ("include /etc/firejail/whitelist-var-common.inc"). It is currently done for 115 applications.

We added globbing support for --private-bin and whitelisting support for /etc and /usr/share.

--private-lib was enhanced to autodetect GTK2, GTK3 and Qt4 libraries. In the next release we do a test run with this option enabled for the following applications: evince, galculator, gnome-calculator, leafpad, mousepad, transmission-gtk, xcalc, xmr-stak-cpu, atril, mate-color-select, tar, file, strings, gpicview, eom, eog, gedit, pluma

Just for fun, this is a private-bin/private-lib Firefox running on Debian 9:

$ firejail --private-bin=firefox,firefox-esr,sh,which --private-lib=firefox-esr firefox
````


## Profile build  tool

$ firejail --build appname $ firejail --build=appname.profile appname

The command builds a whitelisted profile. If /usr/bin/strace is installed on the system, it also
builds a whitelisted seccomp profile. The program is run in a very relaxed sandbox,
with only --caps.drop=all and --nonewprivs. Programs that raise user privileges are not supported
in order to allow strace to run. Chromium and Chromium-based browsers will not work.

Example:

$ firejail --build /usr/bin/vlc ~/Videos/test.mp4

[...]

############################################

/usr/bin/vlc profile

############################################

Persistent global definitions

include /etc/firejail/globals.local

basic blacklisting

include /etc/firejail/disable-common.inc

include /etc/firejail/disable-devel.inc

include /etc/firejail/disable-passwdmgr.inc

include /etc/firejail/disable-programs.inc

home directory whitelisting

whitelist ~/Videos whitelist ~/.local/share/vlc whitelist ~/.config/vlc include /etc/firejail/whitelist-common.inc

filesystem

private-tmp private-dev private-etc vdpau_wrapper.cfg,udev,drirc,fonts,xdg,gtk-3.0,machine-id,selinux, whitelist /var/lib/menu-xdg

private-bin vlc,

security filters

caps.drop all nonewprivs seccomp

seccomp.keep futex,poll,rt_sigtimedwait,ioctl,fdatasync,read,writev,sendmsg,sendto,write,recvmsg,mmap,mprotect,getpid,stat,clock_nanosleep,munmap,close,access,lseek,fcntl,open,fstat,lstat,brk,rt_sigaction,rt_sigprocmask,rt_sigreturn,madvise,shmget,shmat,shmctl,alarm,socket,connect,recvfrom,shutdown,getsockname,getpeername,setsockopt,getsockopt,clone,execve,uname,shmdt,flock,ftruncate,getdents,rename,mkdir,unlink,readlink,chmod,getrlimit,sysinfo,getuid,getgid,geteuid,getegid,getresuid,getresgid,statfs,fstatfs,prctl,arch_prctl,sched_getaffinity,set_tid_address,fadvise64,clock_getres,tgkill,set_robust_list,eventfd2,dup3,pipe2,getrandom,memfd_create

76 syscalls total

Probably you will need to add more syscalls to seccomp.keep. Look for

seccomp errors in /var/log/syslog or /var/log/audit/audit.log while

running your sandbox.

network

protocol unix,netlink, net none

environment

shell none $

## New command line and profile options

  --writable-run-user
          This    options    disables   the   default   blacklisting   of
          run/user/$UID/systemd and /run/user/$UID/gnupg.

          Example:
          $ sudo firejail --writable-run-user

   --rlimit-as=number
          Set the maximum size of the process's virtual  memory  (address
          space) in bytes.

   --rlimit-cpu=number
          Set  the  maximum limit, in seconds, for the amount of CPU time
          each sandboxed process  can consume. When the limit is reached,
          the processes are killed.

          The  CPU  limit  is  a limit on CPU seconds rather than elapsed
          time. CPU seconds is basically how many  seconds  the  CPU  has
          been  in  use  and  does not necessarily directly relate to the
          elapsed time. Linux kernel keeps track of CPU seconds for  each
          process independently.

   --timeout=hh:mm:ss
          Kill  the sandbox automatically after the time has elapsed. The
          time is specified in hours/minutes/seconds format.

          $ firejail --timeout=01:30:00 firefox

  --debug-private-lib
          Debug messages for --private-lib option.

## New profiles:

terasology, surf, rocketchat, clamscan, clamdscan, clamdtop, freshclam, xmr-stak-cpu,
amule, ardour4, ardour5, brackets, calligra, calligraauthor, calligraconverter,
calligraflow, calligraplan, calligraplanwork, calligrasheets, calligrastage,
calligrawords, cin, dooble, dooble-qt4, fetchmail, freecad, freecadcmd, google-earth,
imagej, karbon, kdenlive, krita, linphone, lmms, macrofusion, mpd, natron, Natron,
ricochet, shotcut, teamspeak3, tor, tor-browser-en, Viber, x-terminal-emulator, zart,
conky, arch-audit, ffmpeg, bluefish, cliqz, cinelerra, openshot-qt, pinta, uefitool,
aosp, pdfmod, gnome-ring, signal-desktop, xcalc, zaproxy, kopete, kget, nheko, Enpass

Upstreamed many profiles from the following sources: https://github.com/chiraag-nataraj/firejail-profiles,
https://github.com/nyancat18/fe, and https://aur.archlinux.org/packages/firejail-profiles.