1FIREJAIL(1) firejail man page FIREJAIL(1)
2
6 Firejail - Linux namespaces sandbox program
7
9 Start a sandbox:
10 firejail [OPTIONS] [program and arguments]
12 Start an AppImage program:
14 firejail [OPTIONS] --appimage [appimage-file and arguments]
16 File transfer from an existing sandbox
18 firejail {--ls | --get | --put | --cat} dir_or_filename
20 Network traffic shaping for an existing sandbox:
22 firejail --bandwidth={name|pid} bandwidth-command
24 Monitoring:
26 firejail {--list | --netstats | --top | --tree}
28 Miscellaneous:
30 firejail {-? | --debug-caps | --debug-errnos | --debug-syscalls
32 | --debug-syscalls32 | --debug-protocols | --help | --version}
33
35 Firejail is a SUID sandbox program that reduces the risk of security
36 breaches by restricting the running environment of untrusted applica‐
37 tions using Linux namespaces, seccomp-bpf and Linux capabilities. It
38 allows a process and all its descendants to have their own private view
39 of the globally shared kernel resources, such as the network stack,
40 process table, mount table. Firejail can work in a SELinux or AppArmor
41 environment, and it is integrated with Linux Control Groups.
42 Written in C with virtually no dependencies, the software runs on any
44 Linux computer with a 3.x kernel version or newer. It can sandbox any
45 type of processes: servers, graphical applications, and even user login
46 sessions.
47 Firejail allows the user to manage application security using security
49 profiles. Each profile defines a set of permissions for a specific
50 application or group of applications. The software includes security
51 profiles for a number of more common Linux programs, such as Mozilla
52 Firefox, Chromium, VLC, Transmission etc.
53 Alternative sandbox technologies like snap (https://snapcraft.io/) and
55 flatpak (https://flatpak.org/) are not supported. Snap and flatpak
56 packages have their own native management tools and will not work when
57 sandboxed with Firejail.
58
61 Without any options, the sandbox consists of a filesystem build in a
62 new mount namespace, and new PID and UTS namespaces. IPC, network and
63 user namespaces can be added using the command line options. The
64 default Firejail filesystem is based on the host filesystem with the
65 main system directories mounted read-only. These directories are /etc,
66 /var, /usr, /bin, /sbin, /lib, /lib32, /libx32 and /lib64. Only /home
67 and /tmp are writable.
68 Upon execution Firejail first looks in ~/.config/firejail/ for a pro‐
70 file and if it doesn't find one, it looks in /etc/firejail/. For pro‐
71 file resolution detail see https://github.com/netblue30/fire‐
72 jail/wiki/Creating-Profiles#locations-and-types. If an appropriate
73 profile is not found, Firejail will use a default profile. The default
74 profile is quite restrictive. In case the application doesn't work, use
75 --noprofile option to disable it. For more information, please see
76 SECURITY PROFILES section below.
77 If a program argument is not specified, Firejail starts /bin/bash
79 shell. Examples:
80 $ firejail [OPTIONS] # starting a /bin/bash shell
82 $ firejail [OPTIONS] firefox # starting Mozilla Firefox
84 # sudo firejail [OPTIONS] /etc/init.d/nginx start
86
89 -- Signal the end of options and disables further option process‐
90 ing.
91 --allow-debuggers
93 Allow tools such as strace and gdb inside the sandbox by
94 whitelisting system calls ptrace and process_vm_readv. This
95 option is only available when running on Linux kernels 4.8 or
96 newer - a kernel bug in ptrace system call allows a full bypass
97 of the seccomp filter.
98 Example:
100 $ firejail --allow-debuggers --profile=/etc/firejail/fire‐
101 fox.profile strace -f firefox
102 --allusers
104 All directories under /home are visible inside the sandbox. By
105 default, only current user home directory is visible.
106 Example:
108 $ firejail --allusers
109 --appimage
111 Sandbox an AppImage (https://appimage.org/) application. If the
112 sandbox is started as a regular user, nonewprivs and a default
113 capabilities filter are enabled. private-bin and private-lib
114 are disabled by default when running appimages.
115 Example:
117 $ firejail --appimage krita-3.0-x86_64.appimage
118 $ firejail --appimage --private krita-3.0-x86_64.appimage
119 #ifdef HAVE_X11 $ firejail --appimage --net=none --x11
120 krita-3.0-x86_64.appimage
121 --audit
123 Audit the sandbox, see AUDIT section for more details.
124 --audit=test-program
126 Audit the sandbox, see AUDIT section for more details.
127 --bandwidth=name|pid
129 Set bandwidth limits for the sandbox identified by name or PID,
130 see TRAFFIC SHAPING section for more details.
131 --bind=filename1,filename2
133 Mount-bind filename1 on top of filename2. This option is only
134 available when running as root.
135 Example:
137 # firejail --bind=/config/etc/passwd,/etc/passwd
138 --blacklist=dirname_or_filename
140 Blacklist directory or file. File globbing is supported, see
141 FILE GLOBBING section for more details.
142 Example:
144 $ firejail --blacklist=/sbin --blacklist=/usr/sbin
145 $ firejail --blacklist=~/.mozilla
146 $ firejail "--blacklist=/home/username/My Virtual Machines"
147 $ firejail --blacklist=/home/username/My\ Virtual\ Machines
148 --build
150 The command builds a whitelisted profile. The profile is printed
151 on the screen. If /usr/bin/strace is installed on the system, it
152 also builds a whitelisted seccomp profile. The program is run in
153 a very relaxed sandbox, with only --caps.drop=all and --nonew‐
154 privs. Programs that raise user privileges are not supported in
155 order to allow strace to run. Chromium and Chromium-based
156 browsers will not work.
157 Example:
159 $ firejail --build vlc ~/Videos/test.mp4
160 --build=profile-file
162 The command builds a whitelisted profile, and saves it in pro‐
163 file-file. If /usr/bin/strace is installed on the system, it
164 also builds a whitelisted seccomp profile. The program is run in
165 a very relaxed sandbox, with only --caps.drop=all and --nonew‐
166 privs. Programs that raise user privileges are not supported in
167 order to allow strace to run. Chromium and Chromium-based
168 browsers will not work.
169 Example:
171 $ firejail --build=vlc.profile vlc ~/Videos/test.mp4
172 -c Login shell compatibility option. This option is use by some
174 login programs when executing the login shell, such as when
175 firejail is used as a restricted login shell. It currently does
176 not change the execution of firejail.
177 --caps Linux capabilities is a kernel feature designed to split up the
179 root privilege into a set of distinct privileges. These privi‐
180 leges can be enabled or disabled independently, thus restricting
181 what a process running as root can do in the system.
182 By default root programs run with all capabilities enabled.
184 --caps option disables the following capabilities: CAP_SYS_MOD‐
185 ULE, CAP_SYS_RAWIO, CAP_SYS_BOOT, CAP_SYS_NICE, CAP_SYS_TTY_CON‐
186 FIG, CAP_SYSLOG, CAP_MKNOD, CAP_SYS_ADMIN. The filter is
187 applied to all processes started in the sandbox.
188 Example:
190 $ sudo firejail --caps /etc/init.d/nginx start
191 --caps.drop=all
194 Drop all capabilities for the processes running in the sandbox.
195 This option is recommended for running GUI programs or any other
196 program that doesn't require root privileges. It is a must-have
197 option for sandboxing untrusted programs installed from unoffi‐
198 cial sources - such as games, Java programs, etc.
199 Example:
201 $ firejail --caps.drop=all warzone2100
202 --caps.drop=capability,capability,capability
205 Define a custom blacklist Linux capabilities filter.
206 Example:
208 $ firejail --caps.drop=net_broadcast,net_admin,net_raw
209 --caps.keep=capability,capability,capability
212 Define a custom whitelist Linux capabilities filter.
213 Example:
215 $ sudo firejail --caps.keep=chown,net_bind_service,setgid,\
216 setuid /etc/init.d/nginx start
217 --caps.print=name|pid
220 Print the caps filter for the sandbox identified by name or by
221 PID.
222 Example:
224 $ firejail --name=mygame --caps.drop=all warzone2100 &
225 $ firejail --caps.print=mygame
226 Example:
228 $ firejail --list
229 3272:netblue::firejail --private firefox
230 $ firejail --caps.print=3272
231 --cat=name|pid filename
234 Print content of file from sandbox container, see FILE TRANSFER
235 section for more details.
236 --cgroup=tasks-file
238 Place the sandbox in the specified control group. tasks-file is
239 the full path of cgroup tasks file.
240 Example:
242 # firejail --cgroup=/sys/fs/cgroup/g1/tasks
243 --chroot=dirname
245 Chroot the sandbox into a root filesystem. Unlike the regular
246 filesystem container, the system directories are mounted read-
247 write. If the sandbox is started as a regular user, nonewprivs
248 and a default capabilities filter are enabled.
249 Example:
251 $ firejail --chroot=/media/ubuntu warzone2100
252 --cpu=cpu-number,cpu-number,cpu-number
254 Set CPU affinity.
255 Example:
257 $ firejail --cpu=0,1 handbrake
258 --cpu.print=name|pid
261 Print the CPU cores in use by the sandbox identified by name or
262 by PID.
263 Example:
265 $ firejail --name=mygame --caps.drop=all warzone2100 &
266 $ firejail --cpu.print=mygame
267 Example:
269 $ firejail --list
270 3272:netblue::firejail --private firefox
271 $ firejail --cpu.print=3272
272 --dbus-log=file
274 Specify the location for the DBus log file.
275 The log file contains events for both the system and session
277 buses if both of the --dbus-sysem.log and --dbus-user.log
278 options are specified. If no log file path is given, logs are
279 written to the standard output instead.
280 Example:
282 $ firejail --dbus-system=filter --dbus-system.log \
283 --dbus-log=dbus.txt
284 --dbus-system=filter|none
287 Set system DBus sandboxing policy.
288 The filter policy enables the system DBus filter. This option
290 requires installing the xdg-dbus-proxy utility. Permissions for
291 well-known can be specified with the --dbus-system.talk and
292 --dbus-system.own options.
293 The none policy disables access to the system DBus.
295 Only the regular system DBus UNIX socket is handled by this
297 option. To disable the abstract sockets (and force applications
298 to use the filtered UNIX socket) you would need to request a new
299 network namespace using --net command. Another option is to
300 remove unix from the --protocol set.
301 Example:
303 $ firejail --dbus-system=none
304 --dbus-system.broadcast=name=[member][@path]
307 Allows the application to receive broadcast signals from
308 theindicated interface member at the indicated object path
309 exposed by the indicated bus name on the system DBus. The name
310 may have a .* suffix to match all names underneath it, including
311 itself. The interface member may have a .* to match all members
312 of an interface, or be * to match all interfaces. The path may
313 have a /* suffix to indicate all objects underneath it, includ‐
314 ing itself. Omitting the interface member or the object path
315 will match all members and object paths, respectively.
316 Example:
318 $ firejail --dbus-system=filter --dbus-system.broadcast=\
319 org.freedesktop.Notifications=\
320 org.freedesktop.Notifications.*@/org/freedesktop/Notifications
321 --dbus-system.call=name=[member][@path]
324 Allows the application to call the indicated interface member at
325 the indicated object path exposed by the indicated bus name on
326 the system DBus. The name may have a .* suffix to match all
327 names underneath it, including itself. The interface member may
328 have a .* to match all members of an interface, or be * to match
329 all interfaces. The path may have a /* suffix to indicate all
330 objects underneath it, including itself. Omitting the interface
331 member or the object path will match all members and object
332 paths, respectively.
333 Example:
335 $ firejail --dbus-system=filter --dbus-system.call=\
336 org.freedesktop.Notifications=\
337 org.freedesktop.Notifications.*@/org/freedesktop/Notifications
338 --dbus-system.log
341 Turn on DBus logging for the system DBus. This option requires
342 --dbus-system=log.
343 Example:
345 $ firejail --dbus-system=filter --dbus-system.log
346 --dbus-system.own=name
349 Allows the application to own the specified well-known name on
350 the system DBus. The name may have a .* suffix to match all
351 names underneath it, including itself (e.g. "foo.bar.*" matches
352 "foo.bar", "foo.bar.baz" and "foo.bar.baz.quux", but not "foo‐
353 bar").
354 Example:
356 $ firejail --dbus-system=filter --dbus-system.own=\
357 org.gnome.ghex.*
358 --dbus-system.see=name
361 Allows the application to see, but not talk to the specified
362 well-known name on the system DBus. The name may have a .* suf‐
363 fix to match all names underneath it, including itself (e.g.
364 "foo.bar.*" matches "foo.bar", "foo.bar.baz" and
365 "foo.bar.baz.quux", but not "foobar").
366 Example:
368 $ firejail --dbus-system=filter --dbus-system.see=\
369 org.freedesktop.Notifications
370 --dbus-system.talk=name
373 Allows the application to talk to the specified well-known name
374 on the system DBus. The name may have a .* suffix to match all
375 names underneath it, including itself (e.g. "foo.bar.*" matches
376 "foo.bar", "foo.bar.baz" and "foo.bar.baz.quux", but not "foo‐
377 bar").
378 Example:
380 $ firejail --dbus-system=filter --dbus-system.talk=\
381 org.freedesktop.Notifications
382 --dbus-user=filter|none
385 Set session DBus sandboxing policy.
386 The filter policy enables the session DBus filter. This option
388 requires installing the xdg-dbus-proxy utility. Permissions for
389 well-known names can be added with the --dbus-user.talk and
390 --dbus-user.own options.
391 The none policy disables access to the session DBus.
393 Only the regular session DBus UNIX socket is handled by this
395 option. To disable the abstract sockets (and force applications
396 to use the filtered UNIX socket) you would need to request a new
397 network namespace using --net command. Another option is to
398 remove unix from the --protocol set.
399 Example:
401 $ firejail --dbus-user=none
402 --dbus-user.broadcast=name=[member][@path]
405 Allows the application to receive broadcast signals from
406 theindicated interface member at the indicated object path
407 exposed by the indicated bus name on the session DBus. The name
408 may have a .* suffix to match all names underneath it, including
409 itself. The interface member may have a .* to match all members
410 of an interface, or be * to match all interfaces. The path may
411 have a /* suffix to indicate all objects underneath it, includ‐
412 ing itself. Omitting the interface member or the object path
413 will match all members and object paths, respectively.
414 Example:
416 $ firejail --dbus-user=filter --dbus-user.broadcast=\
417 org.freedesktop.Notifications=\
418 org.freedesktop.Notifications.*@/org/freedesktop/Notifications
419 --dbus-user.call=name=[member][@path]
422 Allows the application to call the indicated interface member at
423 the indicated object path exposed by the indicated bus name on
424 the session DBus. The name may have a .* suffix to match all
425 names underneath it, including itself. The interface member may
426 have a .* to match all members of an interface, or be * to match
427 all interfaces. The path may have a /* suffix to indicate all
428 objects underneath it, including itself. Omitting the interface
429 member or the object path will match all members and object
430 paths, respectively.
431 Example:
433 $ firejail --dbus-user=filter --dbus-user.call=\
434 org.freedesktop.Notifications=\
435 org.freedesktop.Notifications.*@/org/freedesktop/Notifications
436 --dbus-user.log
439 Turn on DBus logging for the session DBus. This option requires
440 --dbus-user=log.
441 Example:
443 $ firejail --dbus-user=filter --dbus-user.log
444 --dbus-user.own=name
447 Allows the application to own the specified well-known name on
448 the session DBus. The name may have a .* suffix to match all
449 names underneath it, including itself (e.g. "foo.bar.*" matches
450 "foo.bar", "foo.bar.baz" and "foo.bar.baz.quux", but not "foo‐
451 bar").
452 Example:
454 $ firejail --dbus-user=filter --dbus-user.own=org.gnome.ghex.*
455 --dbus-user.talk=name
458 Allows the application to talk to the specified well-known name
459 on the session DBus. The name may have a .* suffix to match all
460 names underneath it, including itself (e.g. "foo.bar.*" matches
461 "foo.bar", "foo.bar.baz" and "foo.bar.baz.quux", but not "foo‐
462 bar").
463 Example:
465 $ firejail --dbus-user=filter --dbus-user.talk=\
466 org.freedesktop.Notifications
467 --dbus-user.see=name
470 Allows the application to see, but not talk to the specified
471 well-known name on the session DBus. The name may have a .*
472 suffix to match all names underneath it, including itself (e.g.
473 "foo.bar.*" matches "foo.bar", "foo.bar.baz" and
474 "foo.bar.baz.quux", but not "foobar").
475 Example:
477 $ firejail --dbus-user=filter --dbus-user.see=\
478 org.freedesktop.Notifications
479 --debug
481 Print debug messages.
482 Example:
484 $ firejail --debug firefox
485 --debug-blacklists
488 Debug blacklisting.
489 Example:
491 $ firejail --debug-blacklists firefox
492 --debug-caps
495 Print all recognized capabilities in the current Firejail soft‐
496 ware build and exit.
497 Example:
499 $ firejail --debug-caps
500 --debug-errnos
503 Print all recognized error numbers in the current Firejail soft‐
504 ware build and exit.
505 Example:
507 $ firejail --debug-errnos
508 --debug-private-lib
510 Debug messages for --private-lib option.
511 --debug-protocols
513 Print all recognized protocols in the current Firejail software
514 build and exit.
515 Example:
517 $ firejail --debug-protocols
518 --debug-syscalls
520 Print all recognized system calls in the current Firejail soft‐
521 ware build and exit.
522 Example:
524 $ firejail --debug-syscalls
525 --debug-syscalls32
527 Print all recognized 32 bit system calls in the current Firejail
528 software build and exit.
529 --debug-whitelists
531 Debug whitelisting.
532 Example:
534 $ firejail --debug-whitelists firefox
535 --defaultgw=address
537 Use this address as default gateway in the new network names‐
538 pace.
539 Example:
541 $ firejail --net=eth0 --defaultgw=10.10.20.1 firefox
542 --disable-mnt
544 Blacklist /mnt, /media, /run/mount and /run/media access.
545 Example:
547 $ firejail --disable-mnt firefox
548 --deterministic-exit-code
551 Always exit firejail with the first child's exit status. The
552 default behavior is to use the exit status of the final child to
553 exit, which can be nondeterministic.
554 --dns=address
557 Set a DNS server for the sandbox. Up to three DNS servers can be
558 defined. Use this option if you don't trust the DNS setup on
559 your network.
560 Example:
562 $ firejail --dns=8.8.8.8 --dns=8.8.4.4 firefox
563 Note: this feature is not supported on systemd-resolved setups.
565 --dns.print=name|pid
567 Print DNS configuration for a sandbox identified by name or by
568 PID.
569 Example:
571 $ firejail --name=mygame --caps.drop=all warzone2100 &
572 $ firejail --dns.print=mygame
573 Example:
575 $ firejail --list
576 3272:netblue::firejail --private firefox
577 $ firejail --dns.print=3272
578 --env=name=value
581 Set environment variable in the new sandbox.
582 Example:
584 $ firejail --env=LD_LIBRARY_PATH=/opt/test/lib
585 --fs.print=name|pid
588 Print the filesystem log for the sandbox identified by name or
589 by PID.
590 Example:
592 $ firejail --name=mygame --caps.drop=all warzone2100 &
593 $ firejail --fs.print=mygame
594 Example:
596 $ firejail --list
597 3272:netblue::firejail --private firefox
598 $ firejail --fs.print=3272
599 --get=name|pid filename
602 Get a file from sandbox container, see FILE TRANSFER section for
603 more details.
604 -?, --help
606 Print options end exit.
607 --hostname=name
611 Set sandbox hostname.
612 Example:
614 $ firejail --hostname=officepc firefox
615 --hosts-file=file
618 Use file as /etc/hosts.
619 Example:
621 $ firejail --hosts-file=~/myhosts firefox
622 --ignore=command
625 Ignore command in profile file.
626 Example:
628 $ firejail --ignore=shell --ignore=seccomp firefox
629 $ firejail --ignore="net eth0" firefox
630 --interface=interface
633 Move interface in a new network namespace. Up to four --inter‐
634 face options can be specified. Note: wlan devices are not sup‐
635 ported for this option.
636 Example:
638 $ firejail --interface=eth1 --interface=eth0.vlan100
639 --ip=address
642 Assign IP addresses to the last network interface defined by a
643 --net option. A default gateway is assigned by default.
644 Example:
646 $ firejail --net=eth0 --ip=10.10.20.56 firefox
647 --ip=none
650 No IP address and no default gateway are configured for the last
651 interface defined by a --net option. Use this option in case you
652 intend to start an external DHCP client in the sandbox.
653 Example:
655 $ firejail --net=eth0 --ip=none
656 If the corresponding interface doesn't have an IP address con‐
658 figured, this option is enabled by default.
659 --ip=dhcp
662 Acquire an IP address and default gateway for the last interface
663 defined by a --net option, as well as set the DNS servers
664 according to the DHCP response. This option requires the ISC
665 dhclient DHCP client to be installed and will start it automati‐
666 cally inside the sandbox.
667 Example:
669 $ firejail --net=br0 --ip=dhcp
670 This option should not be used in conjunction with the --dns
672 option if the DHCP server is set to configure DNS servers for
673 the clients, because the manually specified DNS servers will be
674 overwritten.
675 The DHCP client will NOT release the DHCP lease when the sandbox
677 terminates. If your DHCP server requires leases to be explic‐
678 itly released, consider running a DHCP client and releasing the
679 lease manually in conjunction with the --net=none option.
680 --ip6=address
683 Assign IPv6 addresses to the last network interface defined by a
684 --net option.
685 Example:
687 $ firejail --net=eth0 --ip6=2001:0db8:0:f101::1/64 firefox
688 Note: you don't need this option if you obtain your ip6 address
690 from router via SLAAC (your ip6 address and default route will
691 be configured by kernel automatically).
692 --ip6=dhcp
695 Acquire an IPv6 address and default gateway for the last inter‐
696 face defined by a --net option, as well as set the DNS servers
697 according to the DHCP response. This option requires the ISC
698 dhclient DHCP client to be installed and will start it automati‐
699 cally inside the sandbox.
700 Example:
702 $ firejail --net=br0 --ip6=dhcp
703 This option should not be used in conjunction with the --dns
705 option if the DHCP server is set to configure DNS servers for
706 the clients, because the manually specified DNS servers will be
707 overwritten.
708 The DHCP client will NOT release the DHCP lease when the sandbox
710 terminates. If your DHCP server requires leases to be explic‐
711 itly released, consider running a DHCP client and releasing the
712 lease manually.
713 --iprange=address,address
716 Assign an IP address in the provided range to the last network
717 interface defined by a --net option. A default gateway is
718 assigned by default.
719 Example:
721 $ firejail --net=eth0 --iprange=192.168.1.100,192.168.1.150
722 --ipc-namespace
725 Enable a new IPC namespace if the sandbox was started as a reg‐
726 ular user. IPC namespace is enabled by default for sandboxes
727 started as root.
728 Example:
730 $ firejail --ipc-namespace firefox
731 --join=name|pid
733 Join the sandbox identified by name or by PID. By default a
734 /bin/bash shell is started after joining the sandbox. If a pro‐
735 gram is specified, the program is run in the sandbox. If --join
736 command is issued as a regular user, all security filters are
737 configured for the new process the same they are configured in
738 the sandbox. If --join command is issued as root, the security
739 filters, cgroups and cpus configurations are not applied to the
740 process joining the sandbox.
741 Example:
743 $ firejail --name=mygame --caps.drop=all warzone2100 &
744 $ firejail --join=mygame
745 Example:
747 $ firejail --list
748 3272:netblue::firejail --private firefox
749 $ firejail --join=3272
750 --join-filesystem=name|pid
753 Join the mount namespace of the sandbox identified by name or
754 PID. By default a /bin/bash shell is started after joining the
755 sandbox. If a program is specified, the program is run in the
756 sandbox. This command is available only to root user. Security
757 filters, cgroups and cpus configurations are not applied to the
758 process joining the sandbox.
759 --join-network=name|pid
761 Join the network namespace of the sandbox identified by name. By
762 default a /bin/bash shell is started after joining the sandbox.
763 If a program is specified, the program is run in the sandbox.
764 This command is available only to root user. Security filters,
765 cgroups and cpus configurations are not applied to the process
766 joining the sandbox. Example:
767 # start firefox
769 $ firejail --net=eth0 --name=browser firefox &
770 # change netfilter configuration
772 $ sudo firejail --join-network=browser bash -c "cat /etc/fire‐
773 jail/nolocal.net | /sbin/iptables-restore"
774 # verify netfilter configuration
776 $ sudo firejail --join-network=browser /sbin/iptables -vL
777 # verify IP addresses
779 $ sudo firejail --join-network=browser ip addr
780 Switching to pid 1932, the first child process inside the sand‐
781 box
782 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state
783 UNKNOWN group default
784 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
785 inet 127.0.0.1/8 scope host lo
786 valid_lft forever preferred_lft forever
787 inet6 ::1/128 scope host
788 valid_lft forever preferred_lft forever
789 2: eth0-1931: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc
790 noqueue state UNKNOWN group default
791 link/ether 76:58:14:42:78:e4 brd ff:ff:ff:ff:ff:ff
792 inet 192.168.1.158/24 brd 192.168.1.255 scope global
793 eth0-1931
794 valid_lft forever preferred_lft forever
795 inet6 fe80::7458:14ff:fe42:78e4/64 scope link
796 valid_lft forever preferred_lft forever
797 --join-or-start=name
799 Join the sandbox identified by name or start a new one. Same as
800 "firejail --join=name" if sandbox with specified name exists,
801 otherwise same as "firejail --name=name ..."
802 Note that in contrary to other join options there is respective
803 profile option.
804 --keep-dev-shm
807 /dev/shm directory is untouched (even with --private-dev)
808 Example:
810 $ firejail --keep-dev-shm --private-dev
811 --keep-var-tmp
814 /var/tmp directory is untouched.
815 Example:
817 $ firejail --keep-var-tmp
818 --list List all sandboxes, see MONITORING section for more details.
821 Example:
823 $ firejail --list
824 7015:netblue:browser:firejail firefox
825 7056:netblue:torrent:firejail --net=eth0 transmission-gtk
826 7064:netblue::firejail --noroot xterm
827 --ls=name|pid dir_or_filename
829 List files in sandbox container, see FILE TRANSFER section for
830 more details.
831 --mac=address
833 Assign MAC addresses to the last network interface defined by a
834 --net option. This option is not supported for wireless inter‐
835 faces.
836 Example:
838 $ firejail --net=eth0 --mac=00:11:22:33:44:55 firefox
839 --machine-id
841 Spoof id number in /etc/machine-id file - a new random id is
842 generated inside the sandbox. Note that this breaks audio sup‐
843 port. Enable it when sound is not required.
844 Example:
846 $ firejail --machine-id
847 --memory-deny-write-execute
850 Install a seccomp filter to block attempts to create memory map‐
851 pings that are both writable and executable, to change mappings
852 to be executable, or to create executable shared memory. The
853 filter examines the arguments of mmap, mmap2, mprotect,
854 pkey_mprotect, memfd_create and shmat system calls and returns
855 error EPERM to the process (or kills it or log the attempt, see
856 --seccomp-error-action below) if necessary.
857 Note: shmat is not implemented as a system call on some plat‐
859 forms including i386, and it cannot be handled by seccomp-bpf.
860 --mtu=number
862 Assign a MTU value to the last network interface defined by a
863 --net option.
864 Example:
866 $ firejail --net=eth0 --mtu=1492
867 --name=name
869 Set sandbox name. Several options, such as --join and --shut‐
870 down, can use this name to identify a sandbox.
871 In case the name supplied by the user is already in use by
873 another sandbox, Firejail will assign a new name as "name-PID",
874 where PID is the process ID of the sandbox. This functionality
875 can be disabled at run time in /etc/firejail/firejail.config
876 file, by setting "name-change" flag to "no".
877 Example:
879 $ firejail --name=browser firefox &
880 $ firejail --name=browser --private firefox --no-remote &
881 $ firejail --list
882 1198:netblue:browser:firejail --name=browser firefox
883 1312:netblue:browser-1312:firejail --name=browser --private
884 firefox --no-remote
885 --net=bridge_interface
887 Enable a new network namespace and connect it to this bridge
888 interface. Unless specified with option --ip and --defaultgw,
889 an IP address and a default gateway will be assigned automati‐
890 cally to the sandbox. The IP address is verified using ARP
891 before assignment. The address configured as default gateway is
892 the bridge device IP address. Up to four --net options can be
893 specified.
894 Example:
896 $ sudo brctl addbr br0
897 $ sudo ifconfig br0 10.10.20.1/24
898 $ sudo brctl addbr br1
899 $ sudo ifconfig br1 10.10.30.1/24
900 $ firejail --net=br0 --net=br1
901 --net=ethernet_interface|wireless_interface
904 Enable a new network namespace and connect it to this ethernet
905 interface using the standard Linux macvlan|ipvaln driver. Unless
906 specified with option --ip and --defaultgw, an IP address and a
907 default gateway will be assigned automatically to the sandbox.
908 The IP address is verified using ARP before assignment. The
909 address configured as default gateway is the default gateway of
910 the host. Up to four --net options can be specified. Support
911 for ipvlan driver was introduced in Linux kernel 3.19.
912 Example:
914 $ firejail --net=eth0 --ip=192.168.1.80 --dns=8.8.8.8 firefox
915 $ firejail --net=wlan0 firefox
916 --net=none
918 Enable a new, unconnected network namespace. The only interface
919 available in the new namespace is a new loopback interface (lo).
920 Use this option to deny network access to programs that don't
921 really need network access.
922 Example:
924 $ firejail --net=none vlc
925 Note: --net=none can crash the application on some platforms.
927 In these cases, it can be replaced with --protocol=unix.
928 --net=tap_interface
930 Enable a new network namespace and connect it to this ethernet
931 tap interface using the standard Linux macvlan driver. If the
932 tap interface is not configured, the sandbox will not try to
933 configure the interface inside the sandbox. Please use --ip,
934 --netmask and --defaultgw to specify the configuration.
935 Example:
937 $ firejail --net=tap0 --ip=10.10.20.80 --netmask=255.255.255.0
938 --defaultgw=10.10.20.1 firefox
939 --net.print=name|pid
942 If a new network namespace is enabled, print network interface
943 configuration for the sandbox specified by name or PID. Example:
944 $ firejail --net.print=browser
946 Switching to pid 1853, the first child process inside the sand‐
947 box
948 Interface MAC IP Mask Status
949 lo 127.0.0.1 255.0.0.0 UP
950 eth0-1852 5e:fb:8e:27:29:26 192.168.1.186 255.255.255.0 UP
951 --netfilter
954 Enable a default firewall if a new network namespace is created
955 inside the sandbox. This option has no effect for sandboxes
956 using the system network namespace.
957 The default firewall is optimized for regular desktop applica‐
959 tions. No incoming connections are accepted:
960 *filter
962 :INPUT DROP [0:0]
963 :FORWARD DROP [0:0]
964 :OUTPUT ACCEPT [0:0]
965 -A INPUT -i lo -j ACCEPT
966 -A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
967 # allow ping
968 -A INPUT -p icmp --icmp-type destination-unreachable -j ACCEPT
969 -A INPUT -p icmp --icmp-type time-exceeded -j ACCEPT
970 -A INPUT -p icmp --icmp-type echo-request -j ACCEPT
971 # drop STUN (WebRTC) requests
972 -A OUTPUT -p udp --dport 3478 -j DROP
973 -A OUTPUT -p udp --dport 3479 -j DROP
974 -A OUTPUT -p tcp --dport 3478 -j DROP
975 -A OUTPUT -p tcp --dport 3479 -j DROP
976 COMMIT
977 Example:
979 $ firejail --net=eth0 --netfilter firefox
980 --netfilter=filename
982 Enable the firewall specified by filename if a new network
983 namespace is created inside the sandbox. This option has no
984 effect for sandboxes using the system network namespace.
985 Please use the regular iptables-save/iptables-restore format for
987 the filter file. The following examples are available in
988 /etc/firejail directory:
989 webserver.net is a webserver firewall that allows access only to
991 TCP ports 80 and 443. Example:
992 $ firejail --netfilter=/etc/firejail/webserver.net --net=eth0 \
994 /etc/init.d/apache2 start
995 nolocal.net is a desktop client firewall that disable access to
997 local network. Example:
998 $ firejail --netfilter=/etc/firejail/nolocal.net \
1000 --net=eth0 firefox
1001 --netfilter=filename,arg1,arg2,arg3 ...
1004 This is the template version of the previous command. $ARG1,
1005 $ARG2, $ARG3 ... in the firewall script are replaced with arg1,
1006 arg2, arg3 ... passed on the command line. Up to 16 arguments
1007 are supported. Example:
1008 $ firejail --net=eth0 --ip=192.168.1.105 \
1010 --netfilter=/etc/firejail/tcpserver.net,5001 server-program
1011 --netfilter.print=name|pid
1014 Print the firewall installed in the sandbox specified by name or
1015 PID. Example:
1016 $ firejail --name=browser --net=eth0 --netfilter firefox &
1018 $ firejail --netfilter.print=browser
1019 --netfilter6=filename
1022 Enable the IPv6 firewall specified by filename if a new network
1023 namespace is created inside the sandbox. This option has no
1024 effect for sandboxes using the system network namespace. Please
1025 use the regular iptables-save/iptables-restore format for the
1026 filter file.
1027 --netfilter6.print=name|pid
1030 Print the IPv6 firewall installed in the sandbox specified by
1031 name or PID. Example:
1032 $ firejail --name=browser --net=eth0 --netfilter firefox &
1034 $ firejail --netfilter6.print=browser
1035 --netmask=address
1038 Use this option when you want to assign an IP address in a new
1039 namespace and the parent interface specified by --net is not
1040 configured. An IP address and a default gateway address also
1041 have to be added. By default the new namespace interface comes
1042 without IP address and default gateway configured. Example:
1043 $ sudo /sbin/brctl addbr br0
1045 $ sudo /sbin/ifconfig br0 up
1046 $ firejail --ip=10.10.20.67 --netmask=255.255.255.0
1047 --defaultgw=10.10.20.1
1048 --netns=name
1051 Run the program in a named, persistent network namespace. These
1052 can be created and configured using "ip netns".
1053 --netstats
1056 Monitor network namespace statistics, see MONITORING section for
1057 more details.
1058 Example:
1060 $ firejail --netstats
1062 PID User RX(KB/s) TX(KB/s) Command
1063 1294 netblue 53.355 1.473 firejail --net=eth0 firefox
1064 7383 netblue 9.045 0.112 firejail --net=eth0 transmission
1065 --nice=value
1067 Set nice value for all processes running inside the sandbox.
1068 Only root may specify a negative value.
1069 Example:
1071 $ firejail --nice=2 firefox
1072 --no3d Disable 3D hardware acceleration.
1075 Example:
1077 $ firejail --no3d firefox
1078 --noautopulse
1081 Disable automatic ~/.config/pulse init, for complex setups such
1082 as remote pulse servers or non-standard socket paths.
1083 Example:
1085 $ firejail --noautopulse firefox
1086 --noblacklist=dirname_or_filename
1089 Disable blacklist for this directory or file.
1090 Example:
1092 $ firejail
1093 $ nc dict.org 2628
1094 bash: /bin/nc: Permission denied
1095 $ exit
1096 $ firejail --noblacklist=/bin/nc
1098 $ nc dict.org 2628
1099 220 pan.alephnull.com dictd 1.12.1/rf on Linux 3.14-1-amd64
1100 --nodbus (deprecated)
1102 Disable D-Bus access (both system and session buses). Equivalent
1103 to --dbus-system=none --dbus-user=none.
1104 Example:
1106 $ firejail --nodbus --net=none
1107 --nodvd
1109 Disable DVD and audio CD devices.
1110 Example:
1112 $ firejail --nodvd
1113 --noexec=dirname_or_filename
1115 Remount directory or file noexec, nodev and nosuid. File glob‐
1116 bing is supported, see FILE GLOBBING section for more details.
1117 Example:
1119 $ firejail --noexec=/tmp
1120 /etc and /var are noexec by default if the sandbox was started
1122 as a regular user.
1123 --nogroups
1126 Disable supplementary groups. Without this option, supplementary
1127 groups are enabled for the user starting the sandbox. For root
1128 user supplementary groups are always disabled.
1129 Note: By default all regular user groups are removed with the
1131 exception of the current user. This can be changed using
1132 --allusers command option.
1133 Example:
1135 $ id
1136 uid=1000(netblue) gid=1000(netblue) groups=1000(net‐
1137 blue),24(cdrom),25(floppy),27(sudo),29(audio)
1138 $ firejail --nogroups
1139 Parent pid 8704, child pid 8705
1140 Child process initialized
1141 $ id
1142 uid=1000(netblue) gid=1000(netblue) groups=1000(netblue)
1143 $
1144 --nonewprivs
1147 Sets the NO_NEW_PRIVS prctl. This ensures that child processes
1148 cannot acquire new privileges using execve(2); in particular,
1149 this means that calling a suid binary (or one with file capabil‐
1150 ities) does not result in an increase of privilege. This option
1151 is enabled by default if seccomp filter is activated.
1152 --noprofile
1155 Do not use a security profile.
1156 Example:
1158 $ firejail
1159 Reading profile /etc/firejail/default.profile
1160 Parent pid 8553, child pid 8554
1161 Child process initialized
1162 [...]
1163 $ firejail --noprofile
1165 Parent pid 8553, child pid 8554
1166 Child process initialized
1167 [...] #if HAVE_USERNS
1168 --noroot
1170 Install a user namespace with a single user - the current user.
1171 root user does not exist in the new namespace. This option
1172 requires a Linux kernel version 3.8 or newer. The option is not
1173 supported for --chroot and --overlay configurations, or for
1174 sandboxes started as root.
1175 Example:
1177 $ firejail --noroot
1178 Parent pid 8553, child pid 8554
1179 Child process initialized
1180 $ ping google.com
1181 ping: icmp open socket: Operation not permitted
1182 $
1183 --nosound
1185 Disable sound system.
1186 Example:
1188 $ firejail --nosound firefox
1189 --notv Disable DVB (Digital Video Broadcasting) TV devices.
1192 Example:
1194 $ firejail --notv vlc
1195 --nou2f
1198 Disable U2F devices.
1199 Example:
1201 $ firejail --nou2f
1202 --novideo
1205 Disable video devices.
1206 --nowhitelist=dirname_or_filename
1209 Disable whitelist for this directory or file.
1210 --output=logfile
1213 stdout logging and log rotation. Copy stdout to logfile, and
1214 keep the size of the file under 500KB using log rotation. Five
1215 files with prefixes .1 to .5 are used in rotation.
1216 Example:
1218 $ firejail --output=sandboxlog /bin/bash
1219 [...]
1220 $ ls -l sandboxlog*
1221 -rw-r--r-- 1 netblue netblue 333890 Jun 2 07:48 sandboxlog
1222 -rw-r--r-- 1 netblue netblue 511488 Jun 2 07:48 sandboxlog.1
1223 -rw-r--r-- 1 netblue netblue 511488 Jun 2 07:48 sandboxlog.2
1224 -rw-r--r-- 1 netblue netblue 511488 Jun 2 07:48 sandboxlog.3
1225 -rw-r--r-- 1 netblue netblue 511488 Jun 2 07:48 sandboxlog.4
1226 -rw-r--r-- 1 netblue netblue 511488 Jun 2 07:48 sandboxlog.5
1227 --output-stderr=logfile
1230 Similar to --output, but stderr is also stored.
1231 --overlay
1234 Mount a filesystem overlay on top of the current filesystem.
1235 Unlike the regular filesystem container, the system directories
1236 are mounted read-write. All filesystem modifications go into the
1237 overlay. Directories /run, /tmp and /dev are not covered by the
1238 overlay. The overlay is stored in $HOME/.firejail/<PID> direc‐
1239 tory. If the sandbox is started as a regular user, nonewprivs
1240 and a default capabilities filter are enabled.
1241 OverlayFS support is required in Linux kernel for this option to
1243 work. OverlayFS was officially introduced in Linux kernel ver‐
1244 sion 3.18. This option is not available on Grsecurity systems.
1245 Example:
1247 $ firejail --overlay firefox
1248 --overlay-clean
1251 Clean all overlays stored in $HOME/.firejail directory.
1252 Example:
1254 $ firejail --overlay-clean
1255 --overlay-named=name
1258 Mount a filesystem overlay on top of the current filesystem.
1259 Unlike the regular filesystem container, the system directories
1260 are mounted read-write. All filesystem modifications go into the
1261 overlay. Directories /run, /tmp and /dev are not covered by the
1262 overlay. The overlay is stored in $HOME/.firejail/<NAME> direc‐
1263 tory. The created overlay can be reused between multiple ses‐
1264 sions. If the sandbox is started as a regular user, nonewprivs
1265 and a default capabilities filter are enabled.
1266 OverlayFS support is required in Linux kernel for this option to
1268 work. OverlayFS was officially introduced in Linux kernel ver‐
1269 sion 3.18. This option is not available on Grsecurity systems.
1270 Example:
1272 $ firejail --overlay-named=jail1 firefox
1273 --overlay-tmpfs
1276 Mount a filesystem overlay on top of the current filesystem. All
1277 filesystem modifications are discarded when the sandbox is
1278 closed. Directories /run, /tmp and /dev are not covered by the
1279 overlay. If the sandbox is started as a regular user, nonew‐
1280 privs and a default capabilities filter are enabled.
1281 OverlayFS support is required in Linux kernel for this option to
1283 work. OverlayFS was officially introduced in Linux kernel ver‐
1284 sion 3.18. This option is not available on Grsecurity systems.
1285 Example:
1287 $ firejail --overlay-tmpfs firefox
1288 --private
1290 Mount new /root and /home/user directories in temporary filesys‐
1291 tems. All modifications are discarded when the sandbox is
1292 closed.
1293 Example:
1295 $ firejail --private firefox
1296 --private=directory
1299 Use directory as user home. --private and --private=directory
1300 cannot be used together.
1301 Example:
1303 $ firejail --private=/home/netblue/firefox-home firefox
1304 --private-bin=file,file
1307 Build a new /bin in a temporary filesystem, and copy the pro‐
1308 grams in the list. The files in the list must be expressed as
1309 relative to the /bin, /sbin, /usr/bin, /usr/sbin, or
1310 /usr/local/bin directories. If no listed files are found, /bin
1311 directory will be empty. The same directory is also bind-
1312 mounted over /sbin, /usr/bin, /usr/sbin and /usr/local/bin. All
1313 modifications are discarded when the sandbox is closed. File
1314 globbing is supported, see FILE GLOBBING section for more
1315 details.
1316 Example:
1318 $ firejail --private-bin=bash,sed,ls,cat
1319 Parent pid 20841, child pid 20842
1320 Child process initialized
1321 $ ls /bin
1322 bash cat ls sed
1323 --private-cache
1326 Mount an empty temporary filesystem on top of the .cache direc‐
1327 tory in user home. All modifications are discarded when the
1328 sandbox is closed.
1329 Example:
1331 $ firejail --private-cache openbox
1332 --private-cwd
1335 Set working directory inside jail to the home directory, and
1336 failing that, the root directory.
1337 Does not impact working directory of profile include paths.
1338 Example:
1340 $ pwd
1341 /tmp
1342 $ firejail --private-cwd
1343 $ pwd
1344 /home/user
1345 --private-cwd=directory
1348 Set working directory inside the jail.
1349 Does not impact working directory of profile include paths.
1350 Example:
1352 $ pwd
1353 /tmp
1354 $ firejail --private-cwd=/opt
1355 $ pwd
1356 /opt
1357 --private-dev
1360 Create a new /dev directory. Only disc, dri, dvb, hidraw, null,
1361 full, zero, tty, pts, ptmx, random, snd, urandom, video, log,
1362 shm and usb devices are available. Use the options --no3d,
1363 --nodvd, --nosound, --notv, --nou2f and --novideo for additional
1364 restrictions.
1365 Example:
1367 $ firejail --private-dev
1368 Parent pid 9887, child pid 9888
1369 Child process initialized
1370 $ ls /dev
1371 cdrom cdrw dri dvd dvdrw full log null ptmx pts random
1372 shm snd sr0 tty urandom zero
1373 $
1374 --private-etc=file,directory
1376 Build a new /etc in a temporary filesystem, and copy the files
1377 and directories in the list. The files and directories in the
1378 list must be expressed as relative to the /etc directory. If no
1379 listed file is found, /etc directory will be empty. All modifi‐
1380 cations are discarded when the sandbox is closed.
1381 Example:
1383 $ firejail --private-etc=group,hostname,localtime, \
1384 nsswitch.conf,passwd,resolv.conf,default/motd-news
1385 --private-home=file,directory
1387 Build a new user home in a temporary filesystem, and copy the
1388 files and directories in the list in the new home. The files
1389 and directories in the list must be expressed as relative to the
1390 current user's home directory. All modifications are discarded
1391 when the sandbox is closed.
1392 Example:
1394 $ firejail --private-home=.mozilla firefox
1395 --private-lib=file,directory
1397 This feature is currently under heavy development. Only amd64
1398 platforms are supported at this moment. The files and directo‐
1399 ries in the list must be expressed as relative to the /lib
1400 directory. The idea is to build a new /lib in a temporary
1401 filesystem, with only the library files necessary to run the
1402 application. It could be as simple as:
1403 $ firejail --private-lib galculator
1405 but it gets complicated really fast:
1407 $ firejail --private-lib=x86_64-linux-gnu/xed,x86_64-linux-
1409 gnu/gdk-pixbuf-2.0,libenchant.so.1,librsvg-2.so.2 xed
1410 The feature is integrated with --private-bin:
1412 $ firejail --private-lib --private-bin=bash,ls,ps
1414 $ ls /lib
1415 ld-linux-x86-64.so.2 libgpg-error.so.0 libprocps.so.6 libsys‐
1416 temd.so.0
1417 libc.so.6 liblz4.so.1 libpthread.so.0 libtinfo.so.5
1418 libdl.so.2 liblzma.so.5 librt.so.1 x86_64-linux-gnu
1419 libgcrypt.so.20 libpcre.so.3 libselinux.so.1
1420 $ ps
1421 PID TTY TIME CMD
1422 1 pts/0 00:00:00 firejail
1423 45 pts/0 00:00:00 bash
1424 48 pts/0 00:00:00 ps
1425 $
1426 --private-opt=file,directory
1429 Build a new /opt in a temporary filesystem, and copy the files
1430 and directories in the list. The files and directories in the
1431 list must be expressed as relative to the /opt directory. If no
1432 listed file is found, /opt directory will be empty. All modifi‐
1433 cations are discarded when the sandbox is closed.
1434 Example:
1436 $ firejail --private-opt=firefox /opt/firefox/firefox
1437 --private-srv=file,directory
1440 Build a new /srv in a temporary filesystem, and copy the files
1441 and directories in the list. The files and directories in the
1442 list must be expressed as relative to the /srv directory. If no
1443 listed file is found, /srv directory will be empty. All modifi‐
1444 cations are discarded when the sandbox is closed.
1445 Example:
1447 # firejail --private-srv=www /etc/init.d/apache2 start
1448 --private-tmp
1451 Mount an empty temporary filesystem on top of /tmp directory
1452 whitelisting X11 and PulseAudio sockets.
1453 Example:
1455 $ firejail --private-tmp
1456 $ ls -al /tmp
1457 drwxrwxrwt 4 nobody nogroup 80 Apr 30 11:46 .
1458 drwxr-xr-x 30 nobody nogroup 4096 Apr 26 22:18 ..
1459 drwx------ 2 nobody nogroup 4096 Apr 30 10:52 pulse-PKd‐
1460 htXMmr18n
1461 drwxrwxrwt 2 nobody nogroup 4096 Apr 30 10:52 .X11-unix
1462 --profile=filename_or_profilename
1465 Load a custom security profile from filename. For filename use
1466 an absolute path or a path relative to the current path. For
1467 more information, see SECURITY PROFILES section below.
1468 Example:
1470 $ firejail --profile=myprofile
1471 --profile.print=name|pid
1474 Print the name of the profile file for the sandbox identified by
1475 name or or PID.
1476 Example:
1478 $ firejail --profile.print=browser
1479 /etc/firejail/firefox.profile
1480 --protocol=protocol,protocol,protocol
1482 Enable protocol filter. The filter is based on seccomp and
1483 checks the first argument to socket system call. Recognized
1484 values: unix, inet, inet6, netlink and packet. This option is
1485 not supported for i386 architecture.
1486 Example:
1488 $ firejail --protocol=unix,inet,inet6 firefox
1489 --protocol.print=name|pid
1491 Print the protocol filter for the sandbox identified by name or
1492 PID.
1493 Example:
1495 $ firejail --name=mybrowser firefox &
1496 $ firejail --protocol.print=mybrowser
1497 unix,inet,inet6,netlink
1498 Example:
1500 $ firejail --list
1501 3272:netblue::firejail --private firefox
1502 $ firejail --protocol.print=3272
1503 unix,inet,inet6,netlink
1504 --put=name|pid src-filename dest-filename
1506 Put a file in sandbox container, see FILE TRANSFER section for
1507 more details.
1508 --quiet
1510 Turn off Firejail's output.
1511 The same effect can be obtained by setting an environment vari‐
1513 able FIREJAIL_QUIET to yes.
1514 --read-only=dirname_or_filename
1516 Set directory or file read-only. File globbing is supported, see
1517 FILE GLOBBING section for more details.
1518 Example:
1520 $ firejail --read-only=~/.mozilla firefox
1521 --read-write=dirname_or_filename
1523 Set directory or file read-write. Only files or directories
1524 belonging to the current user are allowed for this operation.
1525 File globbing is supported, see FILE GLOBBING section for more
1526 details. Example:
1527 $ mkdir ~/test
1529 $ touch ~/test/a
1530 $ firejail --read-only=~/test --read-write=~/test/a
1531 --rlimit-as=number
1535 Set the maximum size of the process's virtual memory (address
1536 space) in bytes.
1537 --rlimit-cpu=number
1540 Set the maximum limit, in seconds, for the amount of CPU time
1541 each sandboxed process can consume. When the limit is reached,
1542 the processes are killed.
1543 The CPU limit is a limit on CPU seconds rather than elapsed
1545 time. CPU seconds is basically how many seconds the CPU has been
1546 in use and does not necessarily directly relate to the elapsed
1547 time. Linux kernel keeps track of CPU seconds for each process
1548 independently.
1549 --rlimit-fsize=number
1552 Set the maximum file size that can be created by a process.
1553 --rlimit-nofile=number
1555 Set the maximum number of files that can be opened by a process.
1556 --rlimit-nproc=number
1558 Set the maximum number of processes that can be created for the
1559 real user ID of the calling process.
1560 --rlimit-sigpending=number
1562 Set the maximum number of pending signals for a process.
1563 --rmenv=name
1566 Remove environment variable in the new sandbox.
1567 Example:
1569 $ firejail --rmenv=DBUS_SESSION_BUS_ADDRESS
1570 --scan ARP-scan all the networks from inside a network namespace. This
1572 makes it possible to detect macvlan kernel device drivers run‐
1573 ning on the current host.
1574 Example:
1576 $ firejail --net=eth0 --scan
1577 --seccomp
1579 Enable seccomp filter and blacklist the syscalls in the default
1580 list, which is @default-nodebuggers unless allow-debuggers is
1581 specified, then it is @default.
1582 To help creating useful seccomp filters more easily, the follow‐
1584 ing system call groups are defined: @aio, @basic-io, @chown,
1585 @clock, @cpu-emulation, @debug, @default, @default-nodebuggers,
1586 @default-keep, @file-system, @io-event, @ipc, @keyring, @mem‐
1587 lock, @module, @mount, @network-io, @obsolete, @privileged,
1588 @process, @raw-io, @reboot, @resources, @setuid, @swap, @sync,
1589 @system-service and @timer. More information about groups can
1590 be found in /usr/share/doc/firejail/syscalls.txt
1591 In addition, a system call can be specified by its number
1593 instead of name with prefix $, so for example $165 would be
1594 equal to mount on i386. Exceptions can be allowed with prefix
1595 !.
1596 System architecture is strictly imposed only if flag --sec‐
1598 comp.block-secondary is used. The filter is applied at run time
1599 only if the correct architecture was detected. For the case of
1600 I386 and AMD64 both 32-bit and 64-bit filters are installed. On
1601 a 64 bit architecture, an additional filter for 32 bit system
1602 calls can be installed with --seccomp.32.
1603 Firejail will print seccomp violations to the audit log if the
1605 kernel was compiled with audit support (CONFIG_AUDIT flag).
1606 Example:
1608 $ firejail --seccomp
1609 --seccomp=syscall,@group,!syscall2
1611 Enable seccomp filter, whitelist "syscall2", but blacklist the
1612 default list and the syscalls or syscall groups specified by the
1613 command.
1614 Example:
1616 $ firejail --seccomp=utime,utimensat,utimes firefox
1617 $ firejail --seccomp=@clock,mkdir,unlinkat transmission-gtk
1618 Instead of dropping the syscall by returning EPERM, another
1620 error number can be returned using syscall:errno syntax. This
1621 can be also changed globally with --seccomp-error-action or in
1622 /etc/firejail/firejail.config file. The process can also be
1623 killed by using syscall:kill syntax, or the attempt may be
1624 logged with syscall:log.
1625 Example: $ firejail --seccomp=unlinkat:ENOENT,utimensat,utimes
1627 Parent pid 10662, child pid 10663
1628 Child process initialized
1629 $ touch testfile
1630 $ rm testfile
1631 rm: cannot remove `testfile': Operation not permitted
1632 If the blocked system calls would also block Firejail from oper‐
1634 ating, they are handled by adding a preloaded library which per‐
1635 forms seccomp system calls later. However, this is incompatible
1636 with 32 bit seccomp filters.
1637 Example:
1639 $ firejail --noprofile --shell=none --seccomp=execve bash
1640 Parent pid 32751, child pid 32752
1641 Post-exec seccomp protector enabled
1642 list in: execve, check list: @default-keep prelist: (null),
1643 postlist: execve
1644 Child process initialized in 46.44 ms
1645 $ ls
1646 Bad system call
1647 --seccomp.block-secondary
1650 Enable seccomp filter and filter system call architectures so
1651 that only the native architecture is allowed. For example, on
1652 amd64, i386 and x32 system calls are blocked as well as changing
1653 the execution domain with personality(2) system call.
1654 --seccomp.drop=syscall,@group
1657 Enable seccomp filter, and blacklist the syscalls or the syscall
1658 groups specified by the command. On a 64 bit architecture, an
1659 additional filter for 32 bit system calls can be installed with
1660 --seccomp.32.drop.
1661 Example:
1663 $ firejail --seccomp.drop=utime,utimensat,utimes,@clock
1664 Instead of dropping the syscall by returning EPERM, another
1666 error number can be returned using syscall:errno syntax. This
1667 can be also changed globally with --seccomp-error-action or in
1668 /etc/firejail/firejail.config file. The process can also be
1669 killed by using syscall:kill syntax, or the attempt may be
1670 logged with syscall:log.
1671 Example:
1673 $ firejail --seccomp.drop=unlinkat:ENOENT,utimensat,utimes
1674 Parent pid 10662, child pid 10663
1675 Child process initialized
1676 $ touch testfile
1677 $ rm testfile
1678 rm: cannot remove `testfile': Operation not permitted
1679 --seccomp.keep=syscall,@group,!syscall2
1686 Enable seccomp filter, blacklist all syscall not listed and
1687 "syscall2". The system calls needed by Firejail (group
1688 @default-keep: prctl, execve) are handled with the preload
1689 library. On a 64 bit architecture, an additional filter for 32
1690 bit system calls can be installed with --seccomp.32.keep.
1691 Example:
1693 $ firejail --shell=none --seccomp.keep=poll,select,[...] trans‐
1694 mission-gtk
1695 --seccomp.print=name|pid
1698 Print the seccomp filter for the sandbox identified by name or
1699 PID.
1700 Example:
1702 $ firejail --name=browser firefox &
1703 $ firejail --seccomp.print=browser
1704 line OP JT JF K
1705 =================================
1706 0000: 20 00 00 00000004 ld data.architecture
1707 0001: 15 01 00 c000003e jeq ARCH_64 0003 (false 0002)
1708 0002: 06 00 00 7fff0000 ret ALLOW
1709 0003: 20 00 00 00000000 ld data.syscall-number
1710 0004: 35 01 00 40000000 jge X32_ABI true:0006 (false 0005)
1711 0005: 35 01 00 00000000 jge read 0007 (false 0006)
1712 0006: 06 00 00 00050001 ret ERRNO(1)
1713 0007: 15 41 00 0000009a jeq modify_ldt 0049 (false 0008)
1714 0008: 15 40 00 000000d4 jeq lookup_dcookie 0049 (false 0009)
1715 0009: 15 3f 00 0000012a jeq perf_event_open 0049 (false 000a)
1716 000a: 15 3e 00 00000137 jeq process_vm_writev 0049 (false
1717 000b)
1718 000b: 15 3d 00 0000009c jeq _sysctl 0049 (false 000c)
1719 000c: 15 3c 00 000000b7 jeq afs_syscall 0049 (false 000d)
1720 000d: 15 3b 00 000000ae jeq create_module 0049 (false 000e)
1721 000e: 15 3a 00 000000b1 jeq get_kernel_syms 0049 (false 000f)
1722 000f: 15 39 00 000000b5 jeq getpmsg 0049 (false 0010)
1723 0010: 15 38 00 000000b6 jeq putpmsg 0049 (false 0011)
1724 0011: 15 37 00 000000b2 jeq query_module 0049 (false 0012)
1725 0012: 15 36 00 000000b9 jeq security 0049 (false 0013)
1726 0013: 15 35 00 0000008b jeq sysfs 0049 (false 0014)
1727 0014: 15 34 00 000000b8 jeq tuxcall 0049 (false 0015)
1728 0015: 15 33 00 00000086 jeq uselib 0049 (false 0016)
1729 0016: 15 32 00 00000088 jeq ustat 0049 (false 0017)
1730 0017: 15 31 00 000000ec jeq vserver 0049 (false 0018)
1731 0018: 15 30 00 0000009f jeq adjtimex 0049 (false 0019)
1732 0019: 15 2f 00 00000131 jeq clock_adjtime 0049 (false 001a)
1733 001a: 15 2e 00 000000e3 jeq clock_settime 0049 (false 001b)
1734 001b: 15 2d 00 000000a4 jeq settimeofday 0049 (false 001c)
1735 001c: 15 2c 00 000000b0 jeq delete_module 0049 (false 001d)
1736 001d: 15 2b 00 00000139 jeq finit_module 0049 (false 001e)
1737 001e: 15 2a 00 000000af jeq init_module 0049 (false 001f)
1738 001f: 15 29 00 000000ad jeq ioperm 0049 (false 0020)
1739 0020: 15 28 00 000000ac jeq iopl 0049 (false 0021)
1740 0021: 15 27 00 000000f6 jeq kexec_load 0049 (false 0022)
1741 0022: 15 26 00 00000140 jeq kexec_file_load 0049 (false 0023)
1742 0023: 15 25 00 000000a9 jeq reboot 0049 (false 0024)
1743 0024: 15 24 00 000000a7 jeq swapon 0049 (false 0025)
1744 0025: 15 23 00 000000a8 jeq swapoff 0049 (false 0026)
1745 0026: 15 22 00 000000a3 jeq acct 0049 (false 0027)
1746 0027: 15 21 00 00000141 jeq bpf 0049 (false 0028)
1747 0028: 15 20 00 000000a1 jeq chroot 0049 (false 0029)
1748 0029: 15 1f 00 000000a5 jeq mount 0049 (false 002a)
1749 002a: 15 1e 00 000000b4 jeq nfsservctl 0049 (false 002b)
1750 002b: 15 1d 00 0000009b jeq pivot_root 0049 (false 002c)
1751 002c: 15 1c 00 000000ab jeq setdomainname 0049 (false 002d)
1752 002d: 15 1b 00 000000aa jeq sethostname 0049 (false 002e)
1753 002e: 15 1a 00 000000a6 jeq umount2 0049 (false 002f)
1754 002f: 15 19 00 00000099 jeq vhangup 0049 (false 0030)
1755 0030: 15 18 00 000000ee jeq set_mempolicy 0049 (false 0031)
1756 0031: 15 17 00 00000100 jeq migrate_pages 0049 (false 0032)
1757 0032: 15 16 00 00000117 jeq move_pages 0049 (false 0033)
1758 0033: 15 15 00 000000ed jeq mbind 0049 (false 0034)
1759 0034: 15 14 00 00000130 jeq open_by_handle_at 0049 (false
1760 0035)
1761 0035: 15 13 00 0000012f jeq name_to_handle_at 0049 (false
1762 0036)
1763 0036: 15 12 00 000000fb jeq ioprio_set 0049 (false 0037)
1764 0037: 15 11 00 00000067 jeq syslog 0049 (false 0038)
1765 0038: 15 10 00 0000012c jeq fanotify_init 0049 (false 0039)
1766 0039: 15 0f 00 00000138 jeq kcmp 0049 (false 003a)
1767 003a: 15 0e 00 000000f8 jeq add_key 0049 (false 003b)
1768 003b: 15 0d 00 000000f9 jeq request_key 0049 (false 003c)
1769 003c: 15 0c 00 000000fa jeq keyctl 0049 (false 003d)
1770 003d: 15 0b 00 000000ce jeq io_setup 0049 (false 003e)
1771 003e: 15 0a 00 000000cf jeq io_destroy 0049 (false 003f)
1772 003f: 15 09 00 000000d0 jeq io_getevents 0049 (false 0040)
1773 0040: 15 08 00 000000d1 jeq io_submit 0049 (false 0041)
1774 0041: 15 07 00 000000d2 jeq io_cancel 0049 (false 0042)
1775 0042: 15 06 00 000000d8 jeq remap_file_pages 0049 (false
1776 0043)
1777 0043: 15 05 00 00000116 jeq vmsplice 0049 (false 0044)
1778 0044: 15 04 00 00000087 jeq personality 0049 (false 0045)
1779 0045: 15 03 00 00000143 jeq userfaultfd 0049 (false 0046)
1780 0046: 15 02 00 00000065 jeq ptrace 0049 (false 0047)
1781 0047: 15 01 00 00000136 jeq process_vm_readv 0049 (false
1782 0048)
1783 0048: 06 00 00 7fff0000 ret ALLOW
1784 0049: 06 00 01 00000000 ret KILL
1785 $
1786 --seccomp-error-action= kill | ERRNO
1789 By default, if a seccomp filter blocks a system call, the
1790 process gets EPERM as the error. With --seccomp-error-
1791 action=error, another error number can be returned, for example
1792 ENOSYS or EACCES. The process can also be killed (like in ver‐
1793 sions <0.9.63 of Firejail) by using --seccomp-error-action=kill
1794 syntax, or the attempt may be logged with --seccomp-error-
1795 action=log. Not killing the process weakens Firejail slightly
1796 when trying to contain intrusion, but it may also allow tighter
1797 filters if the only alternative is to allow a system call.
1798 --shell=none
1801 Run the program directly, without a user shell.
1802 Example:
1804 $ firejail --shell=none script.sh
1805 --shell=program
1807 Set default user shell. Use this shell to run the application
1808 using -c shell option. For example "firejail --shell=/bin/dash
1809 firefox" will start Mozilla Firefox as "/bin/dash -c firefox".
1810 By default Bash shell (/bin/bash) is used.
1811 Example: $firejail --shell=/bin/dash script.sh
1813 --shutdown=name|pid
1815 Shutdown the sandbox identified by name or PID.
1816 Example:
1818 $ firejail --name=mygame --caps.drop=all warzone2100 &
1819 $ firejail --shutdown=mygame
1820 Example:
1822 $ firejail --list
1823 3272:netblue::firejail --private firefox
1824 $ firejail --shutdown=3272
1825 --timeout=hh:mm:ss
1827 Kill the sandbox automatically after the time has elapsed. The
1828 time is specified in hours/minutes/seconds format.
1829 $ firejail --timeout=01:30:00 firefox
1831 --tmpfs=dirname
1833 Mount a writable tmpfs filesystem on directory dirname. This
1834 option is available only when running the sandbox as root. File
1835 globbing is supported, see FILE GLOBBING section for more
1836 details.
1837 Example:
1839 # firejail --tmpfs=/var
1840 --top Monitor the most CPU-intensive sandboxes, see MONITORING section
1842 for more details.
1843 Example:
1845 $ firejail --top
1846 --trace[=filename]
1848 Trace open, access and connect system calls. If filename is
1849 specified, log trace output to filename, otherwise log to con‐
1850 sole.
1851 Example:
1853 $ firejail --trace wget -q www.debian.org
1854 Reading profile /etc/firejail/wget.profile
1855 3:wget:fopen64 /etc/wgetrc:0x5c8e8ce6c0
1856 3:wget:fopen /etc/hosts:0x5c8e8cfb70
1857 3:wget:socket AF_INET SOCK_DGRAM IPPROTO_IP:3
1858 3:wget:connect 3 8.8.8.8 port 53:0
1859 3:wget:socket AF_INET SOCK_STREAM IPPROTO_IP:3
1860 3:wget:connect 3 130.89.148.14 port 80:0
1861 3:wget:fopen64 index.html:0x5c8e8d1a60
1862 parent is shutting down, bye...
1864 --tracelog
1866 This option enables auditing blacklisted files and directories.
1867 A message is sent to syslog in case the file or the directory is
1868 accessed.
1869 Example:
1871 $ firejail --tracelog firefox
1872 Sample messages:
1874 $ sudo tail -f /var/log/syslog
1875 [...]
1876 Dec 3 11:43:25 debian firejail[70]: blacklist violation - sand‐
1877 box 26370, exe firefox, syscall open64, path /etc/shadow
1878 Dec 3 11:46:17 debian firejail[70]: blacklist violation - sand‐
1879 box 26370, exe firefox, syscall opendir, path /boot
1880 [...]
1881 --tree Print a tree of all sandboxed processes, see MONITORING section
1883 for more details.
1884 Example:
1886 $ firejail --tree
1887 11903:netblue:firejail iceweasel
1888 11904:netblue:iceweasel
1889 11957:netblue:/usr/lib/iceweasel/plugin-container
1890 11969:netblue:firejail --net=eth0 transmission-gtk
1891 11970:netblue:transmission-gtk
1892 --tunnel[=devname]
1895 Connect the sandbox to a network overlay/VPN tunnel created by
1896 firetunnel utility. This options tries first the client side of
1897 the tunnel. If this fails, it tries the server side. If multiple
1898 tunnels are active, please specify the tunnel device using
1899 --tunnel=devname.
1900 The available tunnel devices are listed in /etc/firetunnel
1902 directory, one file for each device. The files are regular
1903 firejail profile files containing the network configuration, and
1904 are created and managed by firetunnel utility. By default ftc
1905 is the client-side device and fts is the server-side device. For
1906 more information please see man 1 firetunnel.
1907 Example:
1909 $ firejail --tunnel firefox
1910 --version
1912 Print program version/compile time support and exit.
1913 Example:
1915 $ firejail --version
1916 firejail version 0.9.27
1917 Compile time support:
1919 - AppArmor support is enabled
1920 - AppImage support is enabled
1921 - chroot support is enabled
1922 - file and directory whitelisting support is enabled
1923 - file transfer support is enabled
1924 - firetunnel support is enabled
1925 - networking support is enabled
1926 - overlayfs support is enabled
1927 - private-home support is enabled
1928 - seccomp-bpf support is enabled
1929 - user namespace support is enabled
1930 - X11 sandboxing support is enabled
1931 --veth-name=name
1933 Use this name for the interface connected to the bridge for
1934 --net=bridge_interface commands, instead of the default one.
1935 Example:
1937 $ firejail --net=br0 --veth-name=if0
1938 --whitelist=dirname_or_filename
1940 Whitelist directory or file. A temporary file system is mounted
1941 on the top directory, and the whitelisted files are mount-binded
1942 inside. Modifications to whitelisted files are persistent,
1943 everything else is discarded when the sandbox is closed. The top
1944 directory could be user home, /dev, /etc, /media, /mnt, /opt,
1945 /run/user/$UID, /srv, /sys/module, /tmp, /usr/share and /var.
1946 Symbolic link handling: with the exception of user home, both
1948 the link and the real file should be in the same top directory.
1949 For user home, both the link and the real file should be owned
1950 by the user.
1951 File globbing is supported, see FILE GLOBBING section for more
1953 details.
1954 Example:
1956 $ firejail --noprofile --whitelist=~/.mozilla
1957 $ firejail --whitelist=/tmp/.X11-unix --whitelist=/dev/null
1958 $ firejail "--whitelist=/home/username/My Virtual Machines"
1959 $ firejail --whitelist=~/work* --whitelist=/var/backups*
1960 --writable-etc
1963 Mount /etc directory read-write.
1964 Example:
1966 $ sudo firejail --writable-etc
1967 --writable-run-user
1970 Disable the default blacklisting of /run/user/$UID/systemd and
1971 /run/user/$UID/gnupg.
1972 Example:
1974 $ sudo firejail --writable-run-user
1975 --writable-var
1978 Mount /var directory read-write.
1979 Example:
1981 $ sudo firejail --writable-var
1982 --writable-var-log
1985 Use the real /var/log directory, not a clone. By default, a
1986 tmpfs is mounted on top of /var/log directory, and a skeleton
1987 filesystem is created based on the original /var/log.
1988 Example:
1990 $ sudo firejail --writable-var-log
1991 #ifdef HAVE_X11
1993 --x11 Sandbox the application using Xpra, Xephyr, Xvfb or Xorg secu‐
1995 rity extension. The sandbox will prevent screenshot and keylog‐
1996 ger applications started inside the sandbox from accessing
1997 clients running outside the sandbox. Firejail will try Xpra
1998 first, and if Xpra is not installed on the system, it will try
1999 to find Xephyr. If all fails, Firejail will not attempt to use
2000 Xvfb or X11 security extension.
2001 Xpra, Xephyr and Xvfb modes require a network namespace to be
2003 instantiated in order to disable X11 abstract Unix socket. If
2004 this is not possible, the user can disable the abstract socket
2005 by adding "-nolisten local" on Xorg command line at system
2006 level.
2007 Example:
2009 $ firejail --x11 --net=eth0 firefox
2010 --x11=none
2013 Blacklist /tmp/.X11-unix directory, ${HOME}/.Xauthority and the
2014 file specified in ${XAUTHORITY} environment variable. Remove
2015 DISPLAY and XAUTHORITY environment variables. Stop with error
2016 message if X11 abstract socket will be accessible in jail.
2017 --x11=xephyr
2020 Start Xephyr and attach the sandbox to this server. Xephyr is a
2021 display server implementing the X11 display server protocol. A
2022 network namespace needs to be instantiated in order to deny
2023 access to X11 abstract Unix domain socket.
2024 Xephyr runs in a window just like any other X11 application. The
2026 default window size is 800x600. This can be modified in
2027 /etc/firejail/firejail.config file.
2028 The recommended way to use this feature is to run a window man‐
2030 ager inside the sandbox. A security profile for OpenBox is pro‐
2031 vided.
2032 Xephyr is developed by Xorg project. On Debian platforms it is
2034 installed with the command sudo apt-get install xserver-xephyr.
2035 This feature is not available when running as root.
2036 Example:
2038 $ firejail --x11=xephyr --net=eth0 openbox
2039 --x11=xorg
2042 Sandbox the application using the untrusted mode implemented by
2043 X11 security extension. The extension is available in Xorg
2044 package and it is installed by default on most Linux distribu‐
2045 tions. It provides support for a simple trusted/untrusted con‐
2046 nection model. Untrusted clients are restricted in certain ways
2047 to prevent them from reading window contents of other clients,
2048 stealing input events, etc.
2049 The untrusted mode has several limitations. A lot of regular
2051 programs assume they are a trusted X11 clients and will crash
2052 or lock up when run in untrusted mode. Chromium browser and
2053 xterm are two examples. Firefox and transmission-gtk seem to be
2054 working fine. A network namespace is not required for this
2055 option.
2056 Example:
2058 $ firejail --x11=xorg firefox
2059 --x11=xpra
2062 Start Xpra (https://xpra.org) and attach the sandbox to this
2063 server. Xpra is a persistent remote display server and client
2064 for forwarding X11 applications and desktop screens. A network
2065 namespace needs to be instantiated in order to deny access to
2066 X11 abstract Unix domain socket.
2067 On Debian platforms Xpra is installed with the command sudo apt-
2069 get install xpra. This feature is not available when running as
2070 root.
2071 Example:
2073 $ firejail --x11=xpra --net=eth0 firefox
2074 --x11=xvfb
2078 Start Xvfb X11 server and attach the sandbox to this server.
2079 Xvfb, short for X virtual framebuffer, performs all graphical
2080 operations in memory without showing any screen output. Xvfb is
2081 mainly used for remote access and software testing on headless
2082 servers.
2083 On Debian platforms Xvfb is installed with the command sudo apt-
2085 get install xvfb. This feature is not available when running as
2086 root.
2087 Example: remote VNC access
2089 On the server we start a sandbox using Xvfb and openbox window
2091 manager. The default size of Xvfb screen is 800x600 - it can be
2092 changed in /etc/firejail/firejail.config (xvfb-screen). Some
2093 sort of networking (--net) is required in order to isolate the
2094 abstract sockets used by other X servers.
2095 $ firejail --net=none --x11=xvfb openbox
2097 *** Attaching to Xvfb display 792 ***
2099 Reading profile /etc/firejail/openbox.profile
2101 Reading profile /etc/firejail/disable-common.inc
2102 Reading profile /etc/firejail/disable-common.local
2103 Parent pid 5400, child pid 5401
2104 On the server we also start a VNC server and attach it to the
2106 display handled by our Xvfb server (792).
2107 $ x11vnc -display :792
2109 On the client machine we start a VNC viewer and use it to con‐
2111 nect to our server:
2112 $ vncviewer
2114 --xephyr-screen=WIDTHxHEIGHT
2117 Set screen size for --x11=xephyr. The setting will overwrite the
2118 default set in /etc/firejail/firejail.config for the current
2119 sandbox. Run xrandr to get a list of supported resolutions on
2120 your computer.
2121 Example:
2123 $ firejail --net=eth0 --x11=xephyr --xephyr-screen=640x480 fire‐
2124 fox
2125
2128 Audit feature allows the user to point out gaps in security profiles.
2129 The implementation replaces the program to be sandboxed with a test
2130 program. By default, we use faudit program distributed with Firejail. A
2131 custom test program can also be supplied by the user. Examples:
2132 Running the default audit program:
2134 $ firejail --audit transmission-gtk
2135 Running a custom audit program:
2137 $ firejail --audit=~/sandbox-test transmission-gtk
2138 In the examples above, the sandbox configures transmission-gtk profile
2140 and starts the test program. The real program, transmission-gtk, will
2141 not be started.
2142 You can also audit a specific profile without specifying a program.
2144 $ firejail --audit --profile=/etc/firejail/zoom.profile
2145 Limitations: audit feature is not implemented for --x11 commands.
2147
2150 A symbolic link to /usr/bin/firejail under the name of a program, will
2151 start the program in Firejail sandbox. The symbolic link should be
2152 placed in the first $PATH position. On most systems, a good place is
2153 /usr/local/bin directory. Example:
2154 Make a firefox symlink to /usr/bin/firejail:
2156 $ sudo ln -s /usr/bin/firejail /usr/local/bin/firefox
2158 Verify $PATH
2160 $ which -a firefox
2162 /usr/local/bin/firefox
2163 /usr/bin/firefox
2164 Starting firefox in this moment, automatically invokes “firejail
2166 firefox”.
2167 This works for clicking on desktop environment icons, menus etc. Use
2169 "firejail --tree" to verify the program is sandboxed.
2170 $ firejail --tree
2172 1189:netblue:firejail firefox
2173 1190:netblue:firejail firefox
2174 1220:netblue:/bin/sh -c "/usr/lib/firefox/firefox"
2175 1221:netblue:/usr/lib/firefox/firefox
2176 We provide a tool that automates all this integration, please see
2178 firecfg(1) for more details.
2179
2182 firejail
2183 Sandbox a regular /bin/bash session.
2184 firejail firefox
2186 Start Mozilla Firefox.
2187 firejail --debug firefox
2189 Debug Firefox sandbox.
2190 firejail --private firefox
2192 Start Firefox with a new, empty home directory.
2193 firejail --net=none vlc
2195 Start VLC in an unconnected network namespace.
2196 firejail --net=eth0 firefox
2198 Start Firefox in a new network namespace. An IP address is
2199 assigned automatically.
2200 firejail --net=br0 --ip=10.10.20.5 --net=br1 --net=br2
2202 Start a /bin/bash session in a new network namespace and connect
2203 it to br0, br1, and br2 host bridge devices. IP addresses are
2204 assigned automatically for the interfaces connected to br1 and
2205 b2
2206 firejail --list
2208 List all sandboxed processes.
2209
2212 Globbing is the operation that expands a wildcard pattern into the
2213 list of pathnames matching the pattern. This pattern is matched
2214 at firejail start, and is NOT UPDATED at runtime. Files match‐
2215 ing a blacklist, but created after firejail start will be acces‐
2216 sible within the jail. Matching is defined by:
2217 - '?' matches any character
2219 - '*' matches any string
2220 - '[' denotes a range of characters
2221 The globbing feature is implemented using glibc glob command. For
2223 more information on the wildcard syntax see man 7 glob.
2224 The following command line options are supported: --blacklist,
2227 --private-bin, --noexec, --read-only, --read-write, --tmpfs, and
2228 --whitelist.
2229 Examples:
2232 $ firejail --private-bin=sh,bash,python*
2234 $ firejail --blacklist=~/dir[1234]
2235 $ firejail --read-only=~/dir[1-4]
2236
2239 These features allow the user to inspect the filesystem container of an
2240 existing sandbox and transfer files between the container and the host
2241 filesystem.
2242 --cat=name|pid filename
2245 Write content of a container file to standard out. The container
2246 is specified by name or PID. If standard out is a terminal, all
2247 ASCII control characters except new line and horizontal tab are
2248 replaced.
2249 --get=name|pid filename
2252 Retrieve the container file and store it on the host in the cur‐
2253 rent working directory. The container is specified by name or
2254 PID.
2255 --ls=name|pid dir_or_filename
2258 List container files. The container is specified by name or PID.
2259 --put=name|pid src-filename dest-filename
2262 Put src-filename in sandbox container. The container is speci‐
2263 fied by name or PID.
2264 Examples:
2267 $ firejail --name=mybrowser --private firefox
2269 $ firejail --ls=mybrowser ~/Downloads
2271 drwxr-xr-x netblue netblue 4096 .
2272 drwxr-xr-x netblue netblue 4096 ..
2273 -rw-r--r-- netblue netblue 7847 x11-x305.png
2274 -rw-r--r-- netblue netblue 6800 x11-x642.png
2275 -rw-r--r-- netblue netblue 34139 xpra-clipboard.png
2276 $ firejail --get=mybrowser ~/Downloads/xpra-clipboard.png
2278 $ firejail --put=mybrowser xpra-clipboard.png ~/Downloads/xpra-
2280 clipboard.png
2281 $ firejail --cat=mybrowser ~/.bashrc
2283
2285 Option --list prints a list of all sandboxes. The format for each
2286 process entry is as follows:
2287 PID:USER:Sandbox Name:Command
2289 Option --tree prints the tree of processes running in the sandbox. The
2291 format for each process entry is as follows:
2292 PID:USER:Sandbox Name:Command
2294 Option --top is similar to the UNIX top command, however it applies
2296 only to sandboxes.
2297 Option --netstats prints network statistics for active sandboxes
2299 installing new network namespaces.
2300 Listed below are the available fields (columns) in alphabetical order
2302 for --top and --netstats options:
2303 Command
2306 Command used to start the sandbox.
2307 CPU% CPU usage, the sandbox share of the elapsed CPU time since the
2309 last screen update
2310 PID Unique process ID for the task controlling the sandbox.
2312 Prcs Number of processes running in sandbox, including the control‐
2314 ling process.
2315 RES Resident Memory Size (KiB), sandbox non-swapped physical memory.
2317 It is a sum of the RES values for all processes running in the
2318 sandbox.
2319 RX(KB/s)
2321 Network receive speed.
2322 Sandbox Name
2324 The name of the sandbox, if any.
2325 SHR Shared Memory Size (KiB), it reflects memory shared with other
2327 processes. It is a sum of the SHR values for all processes run‐
2328 ning in the sandbox, including the controlling process.
2329 TX(KB/s)
2331 Network transmit speed.
2332 Uptime Sandbox running time in hours:minutes:seconds format.
2334 USER The owner of the sandbox.
2336
2339 To configure a restricted shell, replace /bin/bash with /usr/bin/fire‐
2340 jail in /etc/passwd file for each user that needs to be restricted.
2341 Alternatively, you can specify /usr/bin/firejail in adduser command:
2342 adduser --shell /usr/bin/firejail username
2344 Additional arguments passed to firejail executable upon login are
2346 declared in /etc/firejail/login.users file.
2347
2350 Several command line options can be passed to the program using profile
2351 files. Firejail chooses the profile file as follows:
2352 1. If a profile file is provided by the user with --profile=FILE
2354 option, the profile FILE is loaded. If a profile name is given, it is
2355 searched for first in the ~/.config/firejail directory and if not found
2356 then in /etc/firejail directory. Profile names do not include the
2357 .profile suffix. If there is a file with the same name as the given
2358 profile name, it will be used instead of doing the profile search. To
2359 force a profile search, prefix the profile name with a colon (:), eg.
2360 --profile=:PROFILE_NAME. Example:
2361 $ firejail --profile=/home/netblue/icecat.profile icecat
2363 Reading profile /home/netblue/icecat.profile
2364 [...]
2365 $ firejail --profile=icecat icecat-wrapper.sh
2368 Reading profile /etc/firejail/icecat.profile
2369 [...]
2370 2. If a profile file with the same name as the application is present
2372 in ~/.config/firejail directory or in /etc/firejail, the profile is
2373 loaded. ~/.config/firejail takes precedence over /etc/firejail. Exam‐
2374 ple:
2375 $ firejail icecat
2377 Command name #icecat#
2378 Found icecat profile in /home/netblue/.config/firejail directory
2379 Reading profile /home/netblue/.config/firejail/icecat.profile
2380 [...]
2381 3. Use default.profile file if the sandbox is started by a regular
2383 user, or server.profile file if the sandbox is started by root. Fire‐
2384 jail looks for these files in ~/.config/firejail directory, followed by
2385 /etc/firejail directory. To disable default profile loading, use
2386 --noprofile command option. Example:
2387 $ firejail
2389 Reading profile /etc/firejail/default.profile
2390 Parent pid 8553, child pid 8554
2391 Child process initialized
2392 [...]
2393 $ firejail --noprofile
2395 Parent pid 8553, child pid 8554
2396 Child process initialized
2397 [...]
2398 See man 5 firejail-profile for profile file syntax information.
2400
2402 Network bandwidth is an expensive resource shared among all sandboxes
2403 running on a system. Traffic shaping allows the user to increase net‐
2404 work performance by controlling the amount of data that flows into and
2405 out of the sandboxes.
2406 Firejail implements a simple rate-limiting shaper based on Linux com‐
2408 mand tc. The shaper works at sandbox level, and can be used only for
2409 sandboxes configured with new network namespaces.
2410 Set rate-limits:
2412 $ firejail --bandwidth=name|pid set network download upload
2414 Clear rate-limits:
2416 $ firejail --bandwidth=name|pid clear network
2418 Status:
2420 $ firejail --bandwidth=name|pid status
2422 where:
2424 name - sandbox name
2425 pid - sandbox pid
2426 network - network interface as used by --net option
2427 download - download speed in KB/s (kilobyte per second)
2428 upload - upload speed in KB/s (kilobyte per second)
2429 Example:
2431 $ firejail --name=mybrowser --net=eth0 firefox &
2432 $ firejail --bandwidth=mybrowser set eth0 80 20
2433 $ firejail --bandwidth=mybrowser status
2434 $ firejail --bandwidth=mybrowser clear eth0
2435
2437 This program is free software; you can redistribute it and/or modify it
2438 under the terms of the GNU General Public License as published by the
2439 Free Software Foundation; either version 2 of the License, or (at your
2440 option) any later version.
2441 Homepage: https://firejail.wordpress.com
2443
2445 firemon(1), firecfg(1), firejail-profile(5), firejail-login(5), fire‐
2446 jail-users(5), ⟨https://github.com/netblue30/firejail/wiki⟩,
2447 ⟨https://github.com/netblue30/firejail⟩
24480.9.64 Oct 2020 FIREJAIL(1)