1FIREJAIL(1) firejail man page FIREJAIL(1)
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3
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6 Firejail - Linux namespaces sandbox program
7
9 Start a sandbox:
10
11 firejail [OPTIONS] [program and arguments]
12
13 Start an AppImage program:
14
15 firejail [OPTIONS] --appimage [appimage-file and arguments]
16
17 File transfer from an existing sandbox
18
19 firejail {--ls | --get | --put | --cat} dir_or_filename
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21 Network traffic shaping for an existing sandbox:
22
23 firejail --bandwidth={name|pid} bandwidth-command
24
25 Monitoring:
26
27 firejail {--list | --netstats | --top | --tree}
28
29 Miscellaneous:
30
31 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
43 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
48 Firejail allows the user to manage application security using security
49 profiles. Each profile defines a set of permissions for a specific ap‐
50 plication or group of applications. The software includes security pro‐
51 files for a number of more common Linux programs, such as Mozilla Fire‐
52 fox, Chromium, VLC, Transmission etc.
53
54 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
59
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 de‐
64 fault Firejail filesystem is based on the host filesystem with the main
65 system directories mounted read-only. These directories are /etc, /var,
66 /usr, /bin, /sbin, /lib, /lib32, /libx32 and /lib64. Only /home and
67 /tmp are writable.
68
69 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 SE‐
76 CURITY PROFILES section below.
77
78 If a program argument is not specified, Firejail starts the user's pre‐
79 ferred shell. Examples:
80
81 $ firejail [OPTIONS] # starting the program specified in
82 $SHELL, usually /bin/bash
83
84 $ firejail [OPTIONS] firefox # starting Mozilla Firefox
85
86 # sudo firejail [OPTIONS] /etc/init.d/nginx start
87
88
90 -- Signal the end of options and disables further option process‐
91 ing.
92
93 --allow-debuggers
94 Allow tools such as strace and gdb inside the sandbox by
95 whitelisting system calls ptrace and process_vm_readv. This op‐
96 tion is only available when running on Linux kernels 4.8 or
97 newer - a kernel bug in ptrace system call allows a full bypass
98 of the seccomp filter.
99
100 Example:
101 $ firejail --allow-debuggers --profile=/etc/firejail/fire‐
102 fox.profile strace -f firefox
103
104 --allusers
105 All directories under /home are visible inside the sandbox. By
106 default, only current user home directory is visible.
107
108 Example:
109 $ firejail --allusers
110
111 --appimage
112 Sandbox an AppImage (https://appimage.org/) application. If the
113 sandbox is started as a regular user, nonewprivs and a default
114 capabilities filter are enabled. private-bin and private-lib
115 are disabled by default when running appimages.
116
117 Example:
118 $ firejail --appimage krita-3.0-x86_64.appimage
119 $ firejail --appimage --private krita-3.0-x86_64.appimage
120 $ firejail --appimage --net=none --x11 krita-3.0-x86_64.appimage
121
122 --audit
123 Audit the sandbox, see AUDIT section for more details.
124
125 --audit=test-program
126 Audit the sandbox, see AUDIT section for more details.
127
128 --bandwidth=name|pid
129 Set bandwidth limits for the sandbox identified by name or PID,
130 see TRAFFIC SHAPING section for more details.
131
132 --bind=filename1,filename2
133 Mount-bind filename1 on top of filename2. This option is only
134 available when running as root.
135
136 Example:
137 # firejail --bind=/config/etc/passwd,/etc/passwd
138
139 --blacklist=dirname_or_filename
140 Blacklist directory or file. File globbing is supported, see
141 FILE GLOBBING section for more details.
142
143 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
149 --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
158 Example:
159 $ firejail --build vlc ~/Videos/test.mp4
160
161 --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
170 Example:
171 $ firejail --build=vlc.profile vlc ~/Videos/test.mp4
172
173 -c Login shell compatibility option. This option is use by some lo‐
174 gin programs when executing the login shell, such as when fire‐
175 jail is used as a restricted login shell. It currently does not
176 change the execution of firejail.
177
178 --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
183 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 ap‐
187 plied to all processes started in the sandbox.
188
189 Example:
190 $ sudo firejail --caps /etc/init.d/nginx start
191
192
193 --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
200 Example:
201 $ firejail --caps.drop=all warzone2100
202
203
204 --caps.drop=capability,capability,capability
205 Define a custom blacklist Linux capabilities filter.
206
207 Example:
208 $ firejail --caps.drop=net_broadcast,net_admin,net_raw
209
210
211 --caps.keep=capability,capability,capability
212 Define a custom whitelist Linux capabilities filter.
213
214 Example:
215 $ sudo firejail --caps.keep=chown,net_bind_service,setgid,\ se‐
216 tuid /etc/init.d/nginx start
217
218
219 --caps.print=name|pid
220 Print the caps filter for the sandbox identified by name or by
221 PID.
222
223 Example:
224 $ firejail --name=mygame --caps.drop=all warzone2100 &
225 $ firejail --caps.print=mygame
226
227 Example:
228 $ firejail --list
229 3272:netblue::firejail --private firefox
230 $ firejail --caps.print=3272
231
232
233 --cat=name|pid filename
234 Print content of file from sandbox container, see FILE TRANSFER
235 section for more details.
236
237 --cgroup=tasks-file
238 Place the sandbox in the specified control group. tasks-file is
239 the full path of cgroup tasks file.
240
241 Example:
242 # firejail --cgroup=/sys/fs/cgroup/g1/tasks
243
244 --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
250 Example:
251 $ firejail --chroot=/media/ubuntu warzone2100
252
253 --cpu=cpu-number,cpu-number,cpu-number
254 Set CPU affinity.
255
256 Example:
257 $ firejail --cpu=0,1 handbrake
258
259
260 --cpu.print=name|pid
261 Print the CPU cores in use by the sandbox identified by name or
262 by PID.
263
264 Example:
265 $ firejail --name=mygame --caps.drop=all warzone2100 &
266 $ firejail --cpu.print=mygame
267
268 Example:
269 $ firejail --list
270 3272:netblue::firejail --private firefox
271 $ firejail --cpu.print=3272
272
273 --dbus-log=file
274 Specify the location for the DBus log file.
275
276 The log file contains events for both the system and session
277 buses if both of the --dbus-sysem.log and --dbus-user.log op‐
278 tions are specified. If no log file path is given, logs are
279 written to the standard output instead.
280
281 Example:
282 $ firejail --dbus-system=filter --dbus-system.log \
283 --dbus-log=dbus.txt
284
285
286 --dbus-system=filter|none
287 Set system DBus sandboxing policy.
288
289 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
294 The none policy disables access to the system DBus.
295
296 Only the regular system DBus UNIX socket is handled by this op‐
297 tion. To disable the abstract sockets (and force applications to
298 use the filtered UNIX socket) you would need to request a new
299 network namespace using --net command. Another option is to re‐
300 move unix from the --protocol set.
301
302 Example:
303 $ firejail --dbus-system=none
304
305
306 --dbus-system.broadcast=name=[member][@path]
307 Allows the application to receive broadcast signals from
308 theindicated interface member at the indicated object path ex‐
309 posed 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
317 Example:
318 $ firejail --dbus-system=filter --dbus-system.broadcast=\
319 org.freedesktop.Notifications=\
320 org.freedesktop.Notifications.*@/org/freedesktop/Notifications
321
322
323 --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
334 Example:
335 $ firejail --dbus-system=filter --dbus-system.call=\
336 org.freedesktop.Notifications=\
337 org.freedesktop.Notifications.*@/org/freedesktop/Notifications
338
339
340 --dbus-system.log
341 Turn on DBus logging for the system DBus. This option requires
342 --dbus-system=log.
343
344 Example:
345 $ firejail --dbus-system=filter --dbus-system.log
346
347
348 --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
355 Example:
356 $ firejail --dbus-system=filter --dbus-system.own=\
357 org.gnome.ghex.*
358
359
360 --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
367 Example:
368 $ firejail --dbus-system=filter --dbus-system.see=\
369 org.freedesktop.Notifications
370
371
372 --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
379 Example:
380 $ firejail --dbus-system=filter --dbus-system.talk=\
381 org.freedesktop.Notifications
382
383
384 --dbus-user=filter|none
385 Set session DBus sandboxing policy.
386
387 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
392 The none policy disables access to the session DBus.
393
394 Only the regular session DBus UNIX socket is handled by this op‐
395 tion. To disable the abstract sockets (and force applications to
396 use the filtered UNIX socket) you would need to request a new
397 network namespace using --net command. Another option is to re‐
398 move unix from the --protocol set.
399
400 Example:
401 $ firejail --dbus-user=none
402
403
404 --dbus-user.broadcast=name=[member][@path]
405 Allows the application to receive broadcast signals from
406 theindicated interface member at the indicated object path ex‐
407 posed 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
415 Example:
416 $ firejail --dbus-user=filter --dbus-user.broadcast=\
417 org.freedesktop.Notifications=\
418 org.freedesktop.Notifications.*@/org/freedesktop/Notifications
419
420
421 --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
432 Example:
433 $ firejail --dbus-user=filter --dbus-user.call=\
434 org.freedesktop.Notifications=\
435 org.freedesktop.Notifications.*@/org/freedesktop/Notifications
436
437
438 --dbus-user.log
439 Turn on DBus logging for the session DBus. This option requires
440 --dbus-user=log.
441
442 Example:
443 $ firejail --dbus-user=filter --dbus-user.log
444
445
446 --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
453 Example:
454 $ firejail --dbus-user=filter --dbus-user.own=org.gnome.ghex.*
455
456
457 --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
464 Example:
465 $ firejail --dbus-user=filter --dbus-user.talk=\
466 org.freedesktop.Notifications
467
468
469 --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
476 Example:
477 $ firejail --dbus-user=filter --dbus-user.see=\
478 org.freedesktop.Notifications
479
480 --debug
481 Print debug messages.
482
483 Example:
484 $ firejail --debug firefox
485
486
487 --debug-blacklists
488 Debug blacklisting.
489
490 Example:
491 $ firejail --debug-blacklists firefox
492
493
494 --debug-caps
495 Print all recognized capabilities in the current Firejail soft‐
496 ware build and exit.
497
498 Example:
499 $ firejail --debug-caps
500
501
502 --debug-errnos
503 Print all recognized error numbers in the current Firejail soft‐
504 ware build and exit.
505
506 Example:
507 $ firejail --debug-errnos
508
509 --debug-private-lib
510 Debug messages for --private-lib option.
511
512 --debug-protocols
513 Print all recognized protocols in the current Firejail software
514 build and exit.
515
516 Example:
517 $ firejail --debug-protocols
518
519 --debug-syscalls
520 Print all recognized system calls in the current Firejail soft‐
521 ware build and exit.
522
523 Example:
524 $ firejail --debug-syscalls
525
526 --debug-syscalls32
527 Print all recognized 32 bit system calls in the current Firejail
528 software build and exit.
529
530 --debug-whitelists
531 Debug whitelisting.
532
533 Example:
534 $ firejail --debug-whitelists firefox
535
536 --defaultgw=address
537 Use this address as default gateway in the new network name‐
538 space.
539
540 Example:
541 $ firejail --net=eth0 --defaultgw=10.10.20.1 firefox
542
543 --disable-mnt
544 Blacklist /mnt, /media, /run/mount and /run/media access.
545
546 Example:
547 $ firejail --disable-mnt firefox
548
549
550 --deterministic-exit-code
551 Always exit firejail with the first child's exit status. The de‐
552 fault behavior is to use the exit status of the final child to
553 exit, which can be nondeterministic.
554
555
556 --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
561 Example:
562 $ firejail --dns=8.8.8.8 --dns=8.8.4.4 firefox
563
564 Note: this feature is not supported on systemd-resolved setups.
565
566 --dns.print=name|pid
567 Print DNS configuration for a sandbox identified by name or by
568 PID.
569
570 Example:
571 $ firejail --name=mygame --caps.drop=all warzone2100 &
572 $ firejail --dns.print=mygame
573
574 Example:
575 $ firejail --list
576 3272:netblue::firejail --private firefox
577 $ firejail --dns.print=3272
578
579
580 --env=name=value
581 Set environment variable in the new sandbox.
582
583 Example:
584 $ firejail --env=LD_LIBRARY_PATH=/opt/test/lib
585
586
587 --fs.print=name|pid
588 Print the filesystem log for the sandbox identified by name or
589 by PID.
590
591 Example:
592 $ firejail --name=mygame --caps.drop=all warzone2100 &
593 $ firejail --fs.print=mygame
594
595 Example:
596 $ firejail --list
597 3272:netblue::firejail --private firefox
598 $ firejail --fs.print=3272
599
600
601 --get=name|pid filename
602 Get a file from sandbox container, see FILE TRANSFER section for
603 more details.
604
605 -?, --help
606 Print options end exit.
607
608
609
610 --hostname=name
611 Set sandbox hostname.
612
613 Example:
614 $ firejail --hostname=officepc firefox
615
616
617 --hosts-file=file
618 Use file as /etc/hosts.
619
620 Example:
621 $ firejail --hosts-file=~/myhosts firefox
622
623
624 --ignore=command
625 Ignore command in profile file.
626
627 Example:
628 $ firejail --ignore=shell --ignore=seccomp firefox
629 $ firejail --ignore="net eth0" firefox
630
631
632 --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
637 Example:
638 $ firejail --interface=eth1 --interface=eth0.vlan100
639
640
641 --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
645 Example:
646 $ firejail --net=eth0 --ip=10.10.20.56 firefox
647
648
649 --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
654 Example:
655 $ firejail --net=eth0 --ip=none
656
657 If the corresponding interface doesn't have an IP address con‐
658 figured, this option is enabled by default.
659
660
661 --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 ac‐
664 cording 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
668 Example:
669 $ firejail --net=br0 --ip=dhcp
670
671 This option should not be used in conjunction with the --dns op‐
672 tion if the DHCP server is set to configure DNS servers for the
673 clients, because the manually specified DNS servers will be
674 overwritten.
675
676 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
681
682 --ip6=address
683 Assign IPv6 addresses to the last network interface defined by a
684 --net option.
685
686 Example:
687 $ firejail --net=eth0 --ip6=2001:0db8:0:f101::1/64 firefox
688
689 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
693
694 --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
701 Example:
702 $ firejail --net=br0 --ip6=dhcp
703
704 This option should not be used in conjunction with the --dns op‐
705 tion if the DHCP server is set to configure DNS servers for the
706 clients, because the manually specified DNS servers will be
707 overwritten.
708
709 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
714
715 --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 as‐
718 signed by default.
719
720 Example:
721 $ firejail --net=eth0 --iprange=192.168.1.100,192.168.1.150
722
723
724 --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
729 Example:
730 $ firejail --ipc-namespace firefox
731
732 --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
742 Example:
743 $ firejail --name=mygame --caps.drop=all warzone2100 &
744 $ firejail --join=mygame
745
746 Example:
747 $ firejail --list
748 3272:netblue::firejail --private firefox
749 $ firejail --join=3272
750
751
752 --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
760 --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
768 # start firefox
769 $ firejail --net=eth0 --name=browser firefox &
770
771 # change netfilter configuration
772 $ sudo firejail --join-network=browser bash -c "cat /etc/fire‐
773 jail/nolocal.net | /sbin/iptables-restore"
774
775 # verify netfilter configuration
776 $ sudo firejail --join-network=browser /sbin/iptables -vL
777
778 # 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 UN‐
783 KNOWN 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
798 --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
805
806 --keep-dev-shm
807 /dev/shm directory is untouched (even with --private-dev)
808
809 Example:
810 $ firejail --keep-dev-shm --private-dev
811
812
813 --keep-var-tmp
814 /var/tmp directory is untouched.
815
816 Example:
817 $ firejail --keep-var-tmp
818
819
820 --list List all sandboxes, see MONITORING section for more details.
821
822 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
828 --ls=name|pid dir_or_filename
829 List files in sandbox container, see FILE TRANSFER section for
830 more details.
831
832 --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
837 Example:
838 $ firejail --net=eth0 --mac=00:11:22:33:44:55 firefox
839
840 --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
845 Example:
846 $ firejail --machine-id
847
848
849 --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
858 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
861 --mtu=number
862 Assign a MTU value to the last network interface defined by a
863 --net option.
864
865 Example:
866 $ firejail --net=eth0 --mtu=1492
867
868 --name=name
869 Set sandbox name. Several options, such as --join and --shut‐
870 down, can use this name to identify a sandbox.
871
872 In case the name supplied by the user is already in use by an‐
873 other 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
878 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
886 --net=bridge_interface
887 Enable a new network namespace and connect it to this bridge in‐
888 terface. Unless specified with option --ip and --defaultgw, an
889 IP address and a default gateway will be assigned automatically
890 to the sandbox. The IP address is verified using ARP before as‐
891 signment. The address configured as default gateway is the
892 bridge device IP address. Up to four --net options can be speci‐
893 fied.
894
895 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
902
903 --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 ad‐
909 dress 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
913 Example:
914 $ firejail --net=eth0 --ip=192.168.1.80 --dns=8.8.8.8 firefox
915 $ firejail --net=wlan0 firefox
916
917 --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
923 Example:
924 $ firejail --net=none vlc
925
926 Note: --net=none can crash the application on some platforms.
927 In these cases, it can be replaced with --protocol=unix.
928
929 --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
936 Example:
937 $ firejail --net=tap0 --ip=10.10.20.80 --netmask=255.255.255.0
938 --defaultgw=10.10.20.1 firefox
939
940
941 --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
945 $ 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
952
953 --netfilter
954 Enable a default firewall if a new network namespace is created
955 inside the sandbox. This option has no effect for sandboxes us‐
956 ing the system network namespace.
957
958 The default firewall is optimized for regular desktop applica‐
959 tions. No incoming connections are accepted:
960
961 *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
978 Example:
979 $ firejail --net=eth0 --netfilter firefox
980
981 --netfilter=filename
982 Enable the firewall specified by filename if a new network name‐
983 space is created inside the sandbox. This option has no effect
984 for sandboxes using the system network namespace.
985
986 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
990 webserver.net is a webserver firewall that allows access only to
991 TCP ports 80 and 443. Example:
992
993 $ firejail --netfilter=/etc/firejail/webserver.net --net=eth0 \
994 /etc/init.d/apache2 start
995
996 nolocal.net/nolocal6.net is a desktop client firewall that dis‐
997 able access to local network. Example:
998
999 $ firejail --netfilter=/etc/firejail/nolocal.net \
1000 --net=eth0 firefox
1001
1002
1003 --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
1009 $ firejail --net=eth0 --ip=192.168.1.105 \
1010 --netfilter=/etc/firejail/tcpserver.net,5001 server-program
1011
1012
1013 --netfilter.print=name|pid
1014 Print the firewall installed in the sandbox specified by name or
1015 PID. Example:
1016
1017 $ firejail --name=browser --net=eth0 --netfilter firefox &
1018 $ firejail --netfilter.print=browser
1019
1020
1021 --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 ef‐
1024 fect for sandboxes using the system network namespace. Please
1025 use the regular iptables-save/iptables-restore format for the
1026 filter file.
1027
1028
1029 --netfilter6.print=name|pid
1030 Print the IPv6 firewall installed in the sandbox specified by
1031 name or PID. Example:
1032
1033 $ firejail --name=browser --net=eth0 --netfilter firefox &
1034 $ firejail --netfilter6.print=browser
1035
1036
1037 --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
1044 $ sudo /sbin/brctl addbr br0
1045 $ sudo /sbin/ifconfig br0 up
1046 $ firejail --ip=10.10.20.67 --netmask=255.255.255.0 --de‐
1047 faultgw=10.10.20.1
1048
1049
1050 --netns=name
1051 Run the program in a named, persistent network namespace. These
1052 can be created and configured using "ip netns".
1053
1054
1055 --netstats
1056 Monitor network namespace statistics, see MONITORING section for
1057 more details.
1058
1059 Example:
1060
1061 $ 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
1066 --nice=value
1067 Set nice value for all processes running inside the sandbox.
1068 Only root may specify a negative value.
1069
1070 Example:
1071 $ firejail --nice=2 firefox
1072
1073
1074 --no3d Disable 3D hardware acceleration.
1075
1076 Example:
1077 $ firejail --no3d firefox
1078
1079
1080 --noautopulse
1081 Disable automatic ~/.config/pulse init, for complex setups such
1082 as remote pulse servers or non-standard socket paths.
1083
1084 Example:
1085 $ firejail --noautopulse firefox
1086
1087
1088 --noblacklist=dirname_or_filename
1089 Disable blacklist for this directory or file.
1090
1091 Example:
1092 $ firejail
1093 $ nc dict.org 2628
1094 bash: /bin/nc: Permission denied
1095 $ exit
1096
1097 $ 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
1101 --nodbus (deprecated)
1102 Disable D-Bus access (both system and session buses). Equivalent
1103 to --dbus-system=none --dbus-user=none.
1104
1105 Example:
1106 $ firejail --nodbus --net=none
1107
1108 --nodvd
1109 Disable DVD and audio CD devices.
1110
1111 Example:
1112 $ firejail --nodvd
1113
1114 --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
1118 Example:
1119 $ firejail --noexec=/tmp
1120
1121 /etc and /var are noexec by default if the sandbox was started
1122 as a regular user.
1123
1124
1125 --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
1130 Note: By default all regular user groups are removed with the
1131 exception of the current user. This can be changed using --al‐
1132 lusers command option.
1133
1134 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
1145
1146 --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
1153
1154 --noprofile
1155 Do not use a security profile.
1156
1157 Example:
1158 $ firejail
1159 Reading profile /etc/firejail/default.profile
1160 Parent pid 8553, child pid 8554
1161 Child process initialized
1162 [...]
1163
1164 $ firejail --noprofile
1165 Parent pid 8553, child pid 8554
1166 Child process initialized
1167 [...]
1168
1169 --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 re‐
1172 quires 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
1176 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
1184 --nosound
1185 Disable sound system.
1186
1187 Example:
1188 $ firejail --nosound firefox
1189
1190
1191 --notv Disable DVB (Digital Video Broadcasting) TV devices.
1192
1193 Example:
1194 $ firejail --notv vlc
1195
1196
1197 --nou2f
1198 Disable U2F devices.
1199
1200 Example:
1201 $ firejail --nou2f
1202
1203
1204 --novideo
1205 Disable video devices.
1206
1207
1208 --nowhitelist=dirname_or_filename
1209 Disable whitelist for this directory or file.
1210
1211
1212 --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
1217 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
1228
1229 --output-stderr=logfile
1230 Similar to --output, but stderr is also stored.
1231
1232
1233 --private
1234 Mount new /root and /home/user directories in temporary filesys‐
1235 tems. All modifications are discarded when the sandbox is
1236 closed.
1237
1238 Example:
1239 $ firejail --private firefox
1240
1241
1242 --private=directory
1243 Use directory as user home. --private and --private=directory
1244 cannot be used together.
1245
1246 Example:
1247 $ firejail --private=/home/netblue/firefox-home firefox
1248
1249
1250 --private-bin=file,file
1251 Build a new /bin in a temporary filesystem, and copy the pro‐
1252 grams in the list. The files in the list must be expressed as
1253 relative to the /bin, /sbin, /usr/bin, /usr/sbin, or /usr/lo‐
1254 cal/bin directories. If no listed files are found, /bin direc‐
1255 tory will be empty. The same directory is also bind-mounted
1256 over /sbin, /usr/bin, /usr/sbin and /usr/local/bin. All modifi‐
1257 cations are discarded when the sandbox is closed. File globbing
1258 is supported, see FILE GLOBBING section for more details.
1259
1260 Example:
1261 $ firejail --private-bin=bash,sed,ls,cat
1262 Parent pid 20841, child pid 20842
1263 Child process initialized
1264 $ ls /bin
1265 bash cat ls sed
1266
1267
1268 --private-cache
1269 Mount an empty temporary filesystem on top of the .cache direc‐
1270 tory in user home. All modifications are discarded when the
1271 sandbox is closed.
1272
1273 Example:
1274 $ firejail --private-cache openbox
1275
1276
1277 --private-cwd
1278 Set working directory inside jail to the home directory, and
1279 failing that, the root directory.
1280 Does not impact working directory of profile include paths.
1281
1282 Example:
1283 $ pwd
1284 /tmp
1285 $ firejail --private-cwd
1286 $ pwd
1287 /home/user
1288
1289
1290 --private-cwd=directory
1291 Set working directory inside the jail.
1292 Does not impact working directory of profile include paths.
1293
1294 Example:
1295 $ pwd
1296 /tmp
1297 $ firejail --private-cwd=/opt
1298 $ pwd
1299 /opt
1300
1301
1302 --private-dev
1303 Create a new /dev directory. Only disc, dri, dvb, hidraw, null,
1304 full, zero, tty, pts, ptmx, random, snd, urandom, video, log,
1305 shm and usb devices are available. Use the options --no3d,
1306 --nodvd, --nosound, --notv, --nou2f and --novideo for additional
1307 restrictions.
1308
1309 Example:
1310 $ firejail --private-dev
1311 Parent pid 9887, child pid 9888
1312 Child process initialized
1313 $ ls /dev
1314 cdrom cdrw dri dvd dvdrw full log null ptmx pts random
1315 shm snd sr0 tty urandom zero
1316 $
1317
1318 --private-etc=file,directory
1319 Build a new /etc in a temporary filesystem, and copy the files
1320 and directories in the list. The files and directories in the
1321 list must be expressed as relative to the /etc directory. If no
1322 listed file is found, /etc directory will be empty. All modifi‐
1323 cations are discarded when the sandbox is closed.
1324
1325 Example:
1326 $ firejail --private-etc=group,hostname,localtime, \
1327 nsswitch.conf,passwd,resolv.conf,default/motd-news
1328
1329 --private-home=file,directory
1330 Build a new user home in a temporary filesystem, and copy the
1331 files and directories in the list in the new home. The files
1332 and directories in the list must be expressed as relative to the
1333 current user's home directory. All modifications are discarded
1334 when the sandbox is closed.
1335
1336 Example:
1337 $ firejail --private-home=.mozilla firefox
1338
1339 --private-lib=file,directory
1340 This feature is currently under heavy development. Only amd64
1341 platforms are supported at this moment. The files and directo‐
1342 ries in the list must be expressed as relative to the /lib di‐
1343 rectory. The idea is to build a new /lib in a temporary
1344 filesystem, with only the library files necessary to run the ap‐
1345 plication. It could be as simple as:
1346
1347 $ firejail --private-lib galculator
1348
1349 but it gets complicated really fast:
1350
1351 $ firejail --private-lib=x86_64-linux-gnu/xed,x86_64-linux-
1352 gnu/gdk-pixbuf-2.0,libenchant.so.1,librsvg-2.so.2 xed
1353
1354 The feature is integrated with --private-bin:
1355
1356 $ firejail --private-lib --private-bin=bash,ls,ps
1357 $ ls /lib
1358 ld-linux-x86-64.so.2 libgpg-error.so.0 libprocps.so.6 libsys‐
1359 temd.so.0
1360 libc.so.6 liblz4.so.1 libpthread.so.0 libtinfo.so.5
1361 libdl.so.2 liblzma.so.5 librt.so.1 x86_64-linux-gnu
1362 libgcrypt.so.20 libpcre.so.3 libselinux.so.1
1363 $ ps
1364 PID TTY TIME CMD
1365 1 pts/0 00:00:00 firejail
1366 45 pts/0 00:00:00 bash
1367 48 pts/0 00:00:00 ps
1368 $
1369
1370
1371 --private-opt=file,directory
1372 Build a new /opt in a temporary filesystem, and copy the files
1373 and directories in the list. The files and directories in the
1374 list must be expressed as relative to the /opt directory. If no
1375 listed file is found, /opt directory will be empty. All modifi‐
1376 cations are discarded when the sandbox is closed.
1377
1378 Example:
1379 $ firejail --private-opt=firefox /opt/firefox/firefox
1380
1381
1382 --private-srv=file,directory
1383 Build a new /srv in a temporary filesystem, and copy the files
1384 and directories in the list. The files and directories in the
1385 list must be expressed as relative to the /srv directory. If no
1386 listed file is found, /srv directory will be empty. All modifi‐
1387 cations are discarded when the sandbox is closed.
1388
1389 Example:
1390 # firejail --private-srv=www /etc/init.d/apache2 start
1391
1392
1393 --private-tmp
1394 Mount an empty temporary filesystem on top of /tmp directory
1395 whitelisting X11 and PulseAudio sockets.
1396
1397 Example:
1398 $ firejail --private-tmp
1399 $ ls -al /tmp
1400 drwxrwxrwt 4 nobody nogroup 80 Apr 30 11:46 .
1401 drwxr-xr-x 30 nobody nogroup 4096 Apr 26 22:18 ..
1402 drwx------ 2 nobody nogroup 4096 Apr 30 10:52 pulse-PKd‐
1403 htXMmr18n
1404 drwxrwxrwt 2 nobody nogroup 4096 Apr 30 10:52 .X11-unix
1405
1406
1407 --profile=filename_or_profilename
1408 Load a custom security profile from filename. For filename use
1409 an absolute path or a path relative to the current path. For
1410 more information, see SECURITY PROFILES section below.
1411
1412 Example:
1413 $ firejail --profile=myprofile
1414
1415
1416 --profile.print=name|pid
1417 Print the name of the profile file for the sandbox identified by
1418 name or or PID.
1419
1420 Example:
1421 $ firejail --profile.print=browser
1422 /etc/firejail/firefox.profile
1423
1424 --protocol=protocol,protocol,protocol
1425 Enable protocol filter. The filter is based on seccomp and
1426 checks the first argument to socket system call. Recognized
1427 values: unix, inet, inet6, netlink, packet and bluetooth. This
1428 option is not supported for i386 architecture.
1429
1430 Example:
1431 $ firejail --protocol=unix,inet,inet6 firefox
1432
1433 --protocol.print=name|pid
1434 Print the protocol filter for the sandbox identified by name or
1435 PID.
1436
1437 Example:
1438 $ firejail --name=mybrowser firefox &
1439 $ firejail --protocol.print=mybrowser
1440 unix,inet,inet6,netlink
1441
1442 Example:
1443 $ firejail --list
1444 3272:netblue::firejail --private firefox
1445 $ firejail --protocol.print=3272
1446 unix,inet,inet6,netlink
1447
1448 --put=name|pid src-filename dest-filename
1449 Put a file in sandbox container, see FILE TRANSFER section for
1450 more details.
1451
1452 --quiet
1453 Turn off Firejail's output.
1454
1455 The same effect can be obtained by setting an environment vari‐
1456 able FIREJAIL_QUIET to yes.
1457
1458 --read-only=dirname_or_filename
1459 Set directory or file read-only. File globbing is supported, see
1460 FILE GLOBBING section for more details.
1461
1462 Example:
1463 $ firejail --read-only=~/.mozilla firefox
1464
1465 --read-write=dirname_or_filename
1466 Set directory or file read-write. Only files or directories be‐
1467 longing to the current user are allowed for this operation. File
1468 globbing is supported, see FILE GLOBBING section for more de‐
1469 tails. Example:
1470
1471 $ mkdir ~/test
1472 $ touch ~/test/a
1473 $ firejail --read-only=~/test --read-write=~/test/a
1474
1475
1476
1477 --rlimit-as=number
1478 Set the maximum size of the process's virtual memory (address
1479 space) in bytes.
1480
1481
1482 --rlimit-cpu=number
1483 Set the maximum limit, in seconds, for the amount of CPU time
1484 each sandboxed process can consume. When the limit is reached,
1485 the processes are killed.
1486
1487 The CPU limit is a limit on CPU seconds rather than elapsed
1488 time. CPU seconds is basically how many seconds the CPU has been
1489 in use and does not necessarily directly relate to the elapsed
1490 time. Linux kernel keeps track of CPU seconds for each process
1491 independently.
1492
1493
1494 --rlimit-fsize=number
1495 Set the maximum file size that can be created by a process.
1496
1497 --rlimit-nofile=number
1498 Set the maximum number of files that can be opened by a process.
1499
1500 --rlimit-nproc=number
1501 Set the maximum number of processes that can be created for the
1502 real user ID of the calling process.
1503
1504 --rlimit-sigpending=number
1505 Set the maximum number of pending signals for a process.
1506
1507
1508 --rmenv=name
1509 Remove environment variable in the new sandbox.
1510
1511 Example:
1512 $ firejail --rmenv=DBUS_SESSION_BUS_ADDRESS
1513
1514 --scan ARP-scan all the networks from inside a network namespace. This
1515 makes it possible to detect macvlan kernel device drivers run‐
1516 ning on the current host.
1517
1518 Example:
1519 $ firejail --net=eth0 --scan
1520
1521 --seccomp
1522 Enable seccomp filter and blacklist the syscalls in the default
1523 list, which is @default-nodebuggers unless allow-debuggers is
1524 specified, then it is @default.
1525
1526 To help creating useful seccomp filters more easily, the follow‐
1527 ing system call groups are defined: @aio, @basic-io, @chown,
1528 @clock, @cpu-emulation, @debug, @default, @default-nodebuggers,
1529 @default-keep, @file-system, @io-event, @ipc, @keyring, @mem‐
1530 lock, @module, @mount, @network-io, @obsolete, @privileged,
1531 @process, @raw-io, @reboot, @resources, @setuid, @swap, @sync,
1532 @system-service and @timer. More information about groups can
1533 be found in /usr/share/doc/firejail/syscalls.txt
1534
1535 In addition, a system call can be specified by its number in‐
1536 stead of name with prefix $, so for example $165 would be equal
1537 to mount on i386. Exceptions can be allowed with prefix !.
1538
1539 System architecture is strictly imposed only if flag --sec‐
1540 comp.block-secondary is used. The filter is applied at run time
1541 only if the correct architecture was detected. For the case of
1542 I386 and AMD64 both 32-bit and 64-bit filters are installed. On
1543 a 64 bit architecture, an additional filter for 32 bit system
1544 calls can be installed with --seccomp.32.
1545
1546 Firejail will print seccomp violations to the audit log if the
1547 kernel was compiled with audit support (CONFIG_AUDIT flag).
1548
1549 Example:
1550 $ firejail --seccomp
1551
1552 --seccomp=syscall,@group,!syscall2
1553 Enable seccomp filter, whitelist "syscall2", but blacklist the
1554 default list and the syscalls or syscall groups specified by the
1555 command.
1556
1557 Example:
1558 $ firejail --seccomp=utime,utimensat,utimes firefox
1559 $ firejail --seccomp=@clock,mkdir,unlinkat transmission-gtk
1560
1561 Instead of dropping the syscall by returning EPERM, another er‐
1562 ror number can be returned using syscall:errno syntax. This can
1563 be also changed globally with --seccomp-error-action or in
1564 /etc/firejail/firejail.config file. The process can also be
1565 killed by using syscall:kill syntax, or the attempt may be
1566 logged with syscall:log.
1567
1568 Example: $ firejail --seccomp=unlinkat:ENOENT,utimensat,utimes
1569 Parent pid 10662, child pid 10663
1570 Child process initialized
1571 $ touch testfile
1572 $ rm testfile
1573 rm: cannot remove `testfile': Operation not permitted
1574
1575 If the blocked system calls would also block Firejail from oper‐
1576 ating, they are handled by adding a preloaded library which per‐
1577 forms seccomp system calls later. However, this is incompatible
1578 with 32 bit seccomp filters.
1579
1580 Example:
1581 $ firejail --noprofile --shell=none --seccomp=execve bash
1582 Parent pid 32751, child pid 32752
1583 Post-exec seccomp protector enabled
1584 list in: execve, check list: @default-keep prelist: (null),
1585 postlist: execve
1586 Child process initialized in 46.44 ms
1587 $ ls
1588 Bad system call
1589
1590
1591 --seccomp.block-secondary
1592 Enable seccomp filter and filter system call architectures so
1593 that only the native architecture is allowed. For example, on
1594 amd64, i386 and x32 system calls are blocked as well as changing
1595 the execution domain with personality(2) system call.
1596
1597
1598 --seccomp.drop=syscall,@group
1599 Enable seccomp filter, and blacklist the syscalls or the syscall
1600 groups specified by the command. On a 64 bit architecture, an
1601 additional filter for 32 bit system calls can be installed with
1602 --seccomp.32.drop.
1603
1604 Example:
1605 $ firejail --seccomp.drop=utime,utimensat,utimes,@clock
1606
1607 Instead of dropping the syscall by returning EPERM, another er‐
1608 ror number can be returned using syscall:errno syntax. This can
1609 be also changed globally with --seccomp-error-action or in
1610 /etc/firejail/firejail.config file. The process can also be
1611 killed by using syscall:kill syntax, or the attempt may be
1612 logged with syscall:log.
1613
1614 Example:
1615 $ firejail --seccomp.drop=unlinkat:ENOENT,utimensat,utimes
1616 Parent pid 10662, child pid 10663
1617 Child process initialized
1618 $ touch testfile
1619 $ rm testfile
1620 rm: cannot remove `testfile': Operation not permitted
1621
1622
1623
1624
1625
1626
1627 --seccomp.keep=syscall,@group,!syscall2
1628 Enable seccomp filter, blacklist all syscall not listed and
1629 "syscall2". The system calls needed by Firejail (group @de‐
1630 fault-keep: prctl, execve, execveat) are handled with the
1631 preload library. On a 64 bit architecture, an additional filter
1632 for 32 bit system calls can be installed with --seccomp.32.keep.
1633
1634 Example:
1635 $ firejail --shell=none --seccomp.keep=poll,select,[...] trans‐
1636 mission-gtk
1637
1638
1639 --seccomp.print=name|pid
1640 Print the seccomp filter for the sandbox identified by name or
1641 PID.
1642
1643 Example:
1644 $ firejail --name=browser firefox &
1645 $ firejail --seccomp.print=browser
1646 line OP JT JF K
1647 =================================
1648 0000: 20 00 00 00000004 ld data.architecture
1649 0001: 15 01 00 c000003e jeq ARCH_64 0003 (false 0002)
1650 0002: 06 00 00 7fff0000 ret ALLOW
1651 0003: 20 00 00 00000000 ld data.syscall-number
1652 0004: 35 01 00 40000000 jge X32_ABI true:0006 (false 0005)
1653 0005: 35 01 00 00000000 jge read 0007 (false 0006)
1654 0006: 06 00 00 00050001 ret ERRNO(1)
1655 0007: 15 41 00 0000009a jeq modify_ldt 0049 (false 0008)
1656 0008: 15 40 00 000000d4 jeq lookup_dcookie 0049 (false 0009)
1657 0009: 15 3f 00 0000012a jeq perf_event_open 0049 (false 000a)
1658 000a: 15 3e 00 00000137 jeq process_vm_writev 0049 (false
1659 000b)
1660 000b: 15 3d 00 0000009c jeq _sysctl 0049 (false 000c)
1661 000c: 15 3c 00 000000b7 jeq afs_syscall 0049 (false 000d)
1662 000d: 15 3b 00 000000ae jeq create_module 0049 (false 000e)
1663 000e: 15 3a 00 000000b1 jeq get_kernel_syms 0049 (false 000f)
1664 000f: 15 39 00 000000b5 jeq getpmsg 0049 (false 0010)
1665 0010: 15 38 00 000000b6 jeq putpmsg 0049 (false 0011)
1666 0011: 15 37 00 000000b2 jeq query_module 0049 (false 0012)
1667 0012: 15 36 00 000000b9 jeq security 0049 (false 0013)
1668 0013: 15 35 00 0000008b jeq sysfs 0049 (false 0014)
1669 0014: 15 34 00 000000b8 jeq tuxcall 0049 (false 0015)
1670 0015: 15 33 00 00000086 jeq uselib 0049 (false 0016)
1671 0016: 15 32 00 00000088 jeq ustat 0049 (false 0017)
1672 0017: 15 31 00 000000ec jeq vserver 0049 (false 0018)
1673 0018: 15 30 00 0000009f jeq adjtimex 0049 (false 0019)
1674 0019: 15 2f 00 00000131 jeq clock_adjtime 0049 (false 001a)
1675 001a: 15 2e 00 000000e3 jeq clock_settime 0049 (false 001b)
1676 001b: 15 2d 00 000000a4 jeq settimeofday 0049 (false 001c)
1677 001c: 15 2c 00 000000b0 jeq delete_module 0049 (false 001d)
1678 001d: 15 2b 00 00000139 jeq finit_module 0049 (false 001e)
1679 001e: 15 2a 00 000000af jeq init_module 0049 (false 001f)
1680 001f: 15 29 00 000000ad jeq ioperm 0049 (false 0020)
1681 0020: 15 28 00 000000ac jeq iopl 0049 (false 0021)
1682 0021: 15 27 00 000000f6 jeq kexec_load 0049 (false 0022)
1683 0022: 15 26 00 00000140 jeq kexec_file_load 0049 (false 0023)
1684 0023: 15 25 00 000000a9 jeq reboot 0049 (false 0024)
1685 0024: 15 24 00 000000a7 jeq swapon 0049 (false 0025)
1686 0025: 15 23 00 000000a8 jeq swapoff 0049 (false 0026)
1687 0026: 15 22 00 000000a3 jeq acct 0049 (false 0027)
1688 0027: 15 21 00 00000141 jeq bpf 0049 (false 0028)
1689 0028: 15 20 00 000000a1 jeq chroot 0049 (false 0029)
1690 0029: 15 1f 00 000000a5 jeq mount 0049 (false 002a)
1691 002a: 15 1e 00 000000b4 jeq nfsservctl 0049 (false 002b)
1692 002b: 15 1d 00 0000009b jeq pivot_root 0049 (false 002c)
1693 002c: 15 1c 00 000000ab jeq setdomainname 0049 (false 002d)
1694 002d: 15 1b 00 000000aa jeq sethostname 0049 (false 002e)
1695 002e: 15 1a 00 000000a6 jeq umount2 0049 (false 002f)
1696 002f: 15 19 00 00000099 jeq vhangup 0049 (false 0030)
1697 0030: 15 18 00 000000ee jeq set_mempolicy 0049 (false 0031)
1698 0031: 15 17 00 00000100 jeq migrate_pages 0049 (false 0032)
1699 0032: 15 16 00 00000117 jeq move_pages 0049 (false 0033)
1700 0033: 15 15 00 000000ed jeq mbind 0049 (false 0034)
1701 0034: 15 14 00 00000130 jeq open_by_handle_at 0049 (false
1702 0035)
1703 0035: 15 13 00 0000012f jeq name_to_handle_at 0049 (false
1704 0036)
1705 0036: 15 12 00 000000fb jeq ioprio_set 0049 (false 0037)
1706 0037: 15 11 00 00000067 jeq syslog 0049 (false 0038)
1707 0038: 15 10 00 0000012c jeq fanotify_init 0049 (false 0039)
1708 0039: 15 0f 00 00000138 jeq kcmp 0049 (false 003a)
1709 003a: 15 0e 00 000000f8 jeq add_key 0049 (false 003b)
1710 003b: 15 0d 00 000000f9 jeq request_key 0049 (false 003c)
1711 003c: 15 0c 00 000000fa jeq keyctl 0049 (false 003d)
1712 003d: 15 0b 00 000000ce jeq io_setup 0049 (false 003e)
1713 003e: 15 0a 00 000000cf jeq io_destroy 0049 (false 003f)
1714 003f: 15 09 00 000000d0 jeq io_getevents 0049 (false 0040)
1715 0040: 15 08 00 000000d1 jeq io_submit 0049 (false 0041)
1716 0041: 15 07 00 000000d2 jeq io_cancel 0049 (false 0042)
1717 0042: 15 06 00 000000d8 jeq remap_file_pages 0049 (false
1718 0043)
1719 0043: 15 05 00 00000116 jeq vmsplice 0049 (false 0044)
1720 0044: 15 04 00 00000087 jeq personality 0049 (false 0045)
1721 0045: 15 03 00 00000143 jeq userfaultfd 0049 (false 0046)
1722 0046: 15 02 00 00000065 jeq ptrace 0049 (false 0047)
1723 0047: 15 01 00 00000136 jeq process_vm_readv 0049 (false
1724 0048)
1725 0048: 06 00 00 7fff0000 ret ALLOW
1726 0049: 06 00 01 00000000 ret KILL
1727 $
1728
1729
1730 --seccomp-error-action= kill | ERRNO
1731 By default, if a seccomp filter blocks a system call, the
1732 process gets EPERM as the error. With --seccomp-error-action=er‐
1733 ror, another error number can be returned, for example ENOSYS or
1734 EACCES. The process can also be killed (like in versions <0.9.63
1735 of Firejail) by using --seccomp-error-action=kill syntax, or the
1736 attempt may be logged with --seccomp-error-action=log. Not
1737 killing the process weakens Firejail slightly when trying to
1738 contain intrusion, but it may also allow tighter filters if the
1739 only alternative is to allow a system call.
1740
1741
1742 --shell=none
1743 Run the program directly, without a user shell.
1744
1745 Example:
1746 $ firejail --shell=none script.sh
1747
1748 --shell=program
1749 Set default user shell. Use this shell to run the application
1750 using -c shell option. For example "firejail --shell=/bin/dash
1751 firefox" will start Mozilla Firefox as "/bin/dash -c firefox".
1752 By default the user's preferred shell is used.
1753
1754 Example: $firejail --shell=/bin/dash script.sh
1755
1756 --shutdown=name|pid
1757 Shutdown the sandbox identified by name or PID.
1758
1759 Example:
1760 $ firejail --name=mygame --caps.drop=all warzone2100 &
1761 $ firejail --shutdown=mygame
1762
1763 Example:
1764 $ firejail --list
1765 3272:netblue::firejail --private firefox
1766 $ firejail --shutdown=3272
1767
1768 --timeout=hh:mm:ss
1769 Kill the sandbox automatically after the time has elapsed. The
1770 time is specified in hours/minutes/seconds format.
1771
1772 $ firejail --timeout=01:30:00 firefox
1773
1774 --tmpfs=dirname
1775 Mount a writable tmpfs filesystem on directory dirname. This op‐
1776 tion is available only when running the sandbox as root. File
1777 globbing is supported, see FILE GLOBBING section for more de‐
1778 tails.
1779
1780 Example:
1781 # firejail --tmpfs=/var
1782
1783 --top Monitor the most CPU-intensive sandboxes, see MONITORING section
1784 for more details.
1785
1786 Example:
1787 $ firejail --top
1788
1789 --trace[=filename]
1790 Trace open, access and connect system calls. If filename is
1791 specified, log trace output to filename, otherwise log to con‐
1792 sole.
1793
1794 Example:
1795 $ firejail --trace wget -q www.debian.org
1796 Reading profile /etc/firejail/wget.profile
1797 3:wget:fopen64 /etc/wgetrc:0x5c8e8ce6c0
1798 3:wget:fopen /etc/hosts:0x5c8e8cfb70
1799 3:wget:socket AF_INET SOCK_DGRAM IPPROTO_IP:3
1800 3:wget:connect 3 8.8.8.8 port 53:0
1801 3:wget:socket AF_INET SOCK_STREAM IPPROTO_IP:3
1802 3:wget:connect 3 130.89.148.14 port 80:0
1803 3:wget:fopen64 index.html:0x5c8e8d1a60
1804
1805 parent is shutting down, bye...
1806
1807 --tracelog
1808 This option enables auditing blacklisted files and directories.
1809 A message is sent to syslog in case the file or the directory is
1810 accessed.
1811
1812 Example:
1813 $ firejail --tracelog firefox
1814
1815 Sample messages:
1816 $ sudo tail -f /var/log/syslog
1817 [...]
1818 Dec 3 11:43:25 debian firejail[70]: blacklist violation - sand‐
1819 box 26370, exe firefox, syscall open64, path /etc/shadow
1820 Dec 3 11:46:17 debian firejail[70]: blacklist violation - sand‐
1821 box 26370, exe firefox, syscall opendir, path /boot
1822 [...]
1823
1824 --tree Print a tree of all sandboxed processes, see MONITORING section
1825 for more details.
1826
1827 Example:
1828 $ firejail --tree
1829 11903:netblue:firejail iceweasel
1830 11904:netblue:iceweasel
1831 11957:netblue:/usr/lib/iceweasel/plugin-container
1832 11969:netblue:firejail --net=eth0 transmission-gtk
1833 11970:netblue:transmission-gtk
1834
1835
1836 --tunnel[=devname]
1837 Connect the sandbox to a network overlay/VPN tunnel created by
1838 firetunnel utility. This options tries first the client side of
1839 the tunnel. If this fails, it tries the server side. If multiple
1840 tunnels are active, please specify the tunnel device using
1841 --tunnel=devname.
1842
1843 The available tunnel devices are listed in /etc/firetunnel di‐
1844 rectory, one file for each device. The files are regular fire‐
1845 jail profile files containing the network configuration, and are
1846 created and managed by firetunnel utility. By default ftc is
1847 the client-side device and fts is the server-side device. For
1848 more information please see man 1 firetunnel.
1849
1850 Example:
1851 $ firejail --tunnel firefox
1852
1853 --version
1854 Print program version/compile time support and exit.
1855
1856 Example:
1857 $ firejail --version
1858 firejail version 0.9.27
1859
1860 Compile time support:
1861 - AppArmor support is enabled
1862 - AppImage support is enabled
1863 - chroot support is enabled
1864 - file and directory whitelisting support is enabled
1865 - file transfer support is enabled
1866 - firetunnel support is enabled
1867 - networking support is enabled
1868 - overlayfs support is enabled
1869 - private-home support is enabled
1870 - seccomp-bpf support is enabled
1871 - user namespace support is enabled
1872 - X11 sandboxing support is enabled
1873
1874 --veth-name=name
1875 Use this name for the interface connected to the bridge for
1876 --net=bridge_interface commands, instead of the default one.
1877
1878 Example:
1879 $ firejail --net=br0 --veth-name=if0
1880
1881 --whitelist=dirname_or_filename
1882 Whitelist directory or file. A temporary file system is mounted
1883 on the top directory, and the whitelisted files are mount-binded
1884 inside. Modifications to whitelisted files are persistent, ev‐
1885 erything else is discarded when the sandbox is closed. The top
1886 directory could be user home, /dev, /etc, /media, /mnt, /opt,
1887 /run/user/$UID, /srv, /sys/module, /tmp, /usr/share and /var.
1888
1889 Symbolic link handling: with the exception of user home, both
1890 the link and the real file should be in the same top directory.
1891 For user home, both the link and the real file should be owned
1892 by the user.
1893
1894 File globbing is supported, see FILE GLOBBING section for more
1895 details.
1896
1897 Example:
1898 $ firejail --noprofile --whitelist=~/.mozilla
1899 $ firejail --whitelist=/tmp/.X11-unix --whitelist=/dev/null
1900 $ firejail "--whitelist=/home/username/My Virtual Machines"
1901 $ firejail --whitelist=~/work* --whitelist=/var/backups*
1902
1903
1904 --writable-etc
1905 Mount /etc directory read-write.
1906
1907 Example:
1908 $ sudo firejail --writable-etc
1909
1910
1911 --writable-run-user
1912 Disable the default blacklisting of /run/user/$UID/systemd and
1913 /run/user/$UID/gnupg.
1914
1915 Example:
1916 $ sudo firejail --writable-run-user
1917
1918
1919 --writable-var
1920 Mount /var directory read-write.
1921
1922 Example:
1923 $ sudo firejail --writable-var
1924
1925
1926 --writable-var-log
1927 Use the real /var/log directory, not a clone. By default, a
1928 tmpfs is mounted on top of /var/log directory, and a skeleton
1929 filesystem is created based on the original /var/log.
1930
1931 Example:
1932 $ sudo firejail --writable-var-log
1933
1934
1935 --x11 Sandbox the application using Xpra, Xephyr, Xvfb or Xorg secu‐
1936 rity extension. The sandbox will prevent screenshot and keylog‐
1937 ger applications started inside the sandbox from accessing
1938 clients running outside the sandbox. Firejail will try Xpra
1939 first, and if Xpra is not installed on the system, it will try
1940 to find Xephyr. If all fails, Firejail will not attempt to use
1941 Xvfb or X11 security extension.
1942
1943 Xpra, Xephyr and Xvfb modes require a network namespace to be
1944 instantiated in order to disable X11 abstract Unix socket. If
1945 this is not possible, the user can disable the abstract socket
1946 by adding "-nolisten local" on Xorg command line at system
1947 level.
1948
1949 Example:
1950 $ firejail --x11 --net=eth0 firefox
1951
1952
1953 --x11=none
1954 Blacklist /tmp/.X11-unix directory, ${HOME}/.Xauthority and the
1955 file specified in ${XAUTHORITY} environment variable. Remove
1956 DISPLAY and XAUTHORITY environment variables. Stop with error
1957 message if X11 abstract socket will be accessible in jail.
1958
1959
1960 --x11=xephyr
1961 Start Xephyr and attach the sandbox to this server. Xephyr is a
1962 display server implementing the X11 display server protocol. A
1963 network namespace needs to be instantiated in order to deny ac‐
1964 cess to X11 abstract Unix domain socket.
1965
1966 Xephyr runs in a window just like any other X11 application. The
1967 default window size is 800x600. This can be modified in
1968 /etc/firejail/firejail.config file.
1969
1970 The recommended way to use this feature is to run a window man‐
1971 ager inside the sandbox. A security profile for OpenBox is pro‐
1972 vided.
1973
1974 Xephyr is developed by Xorg project. On Debian platforms it is
1975 installed with the command sudo apt-get install xserver-xephyr.
1976 This feature is not available when running as root.
1977
1978 Example:
1979 $ firejail --x11=xephyr --net=eth0 openbox
1980
1981
1982 --x11=xorg
1983 Sandbox the application using the untrusted mode implemented by
1984 X11 security extension. The extension is available in Xorg
1985 package and it is installed by default on most Linux distribu‐
1986 tions. It provides support for a simple trusted/untrusted con‐
1987 nection model. Untrusted clients are restricted in certain ways
1988 to prevent them from reading window contents of other clients,
1989 stealing input events, etc.
1990
1991 The untrusted mode has several limitations. A lot of regular
1992 programs assume they are a trusted X11 clients and will crash
1993 or lock up when run in untrusted mode. Chromium browser and
1994 xterm are two examples. Firefox and transmission-gtk seem to be
1995 working fine. A network namespace is not required for this op‐
1996 tion.
1997
1998 Example:
1999 $ firejail --x11=xorg firefox
2000
2001
2002 --x11=xpra
2003 Start Xpra (https://xpra.org) and attach the sandbox to this
2004 server. Xpra is a persistent remote display server and client
2005 for forwarding X11 applications and desktop screens. A network
2006 namespace needs to be instantiated in order to deny access to
2007 X11 abstract Unix domain socket.
2008
2009 On Debian platforms Xpra is installed with the command sudo apt-
2010 get install xpra. This feature is not available when running as
2011 root.
2012
2013 Example:
2014 $ firejail --x11=xpra --net=eth0 firefox
2015
2016
2017
2018 --x11=xvfb
2019 Start Xvfb X11 server and attach the sandbox to this server.
2020 Xvfb, short for X virtual framebuffer, performs all graphical
2021 operations in memory without showing any screen output. Xvfb is
2022 mainly used for remote access and software testing on headless
2023 servers.
2024
2025 On Debian platforms Xvfb is installed with the command sudo apt-
2026 get install xvfb. This feature is not available when running as
2027 root.
2028
2029 Example: remote VNC access
2030
2031 On the server we start a sandbox using Xvfb and openbox window
2032 manager. The default size of Xvfb screen is 800x600 - it can be
2033 changed in /etc/firejail/firejail.config (xvfb-screen). Some
2034 sort of networking (--net) is required in order to isolate the
2035 abstract sockets used by other X servers.
2036
2037 $ firejail --net=none --x11=xvfb openbox
2038
2039 *** Attaching to Xvfb display 792 ***
2040
2041 Reading profile /etc/firejail/openbox.profile
2042 Reading profile /etc/firejail/disable-common.inc
2043 Reading profile /etc/firejail/disable-common.local
2044 Parent pid 5400, child pid 5401
2045
2046 On the server we also start a VNC server and attach it to the
2047 display handled by our Xvfb server (792).
2048
2049 $ x11vnc -display :792
2050
2051 On the client machine we start a VNC viewer and use it to con‐
2052 nect to our server:
2053
2054 $ vncviewer
2055
2056
2057 --xephyr-screen=WIDTHxHEIGHT
2058 Set screen size for --x11=xephyr. The setting will overwrite the
2059 default set in /etc/firejail/firejail.config for the current
2060 sandbox. Run xrandr to get a list of supported resolutions on
2061 your computer.
2062
2063 Example:
2064 $ firejail --net=eth0 --x11=xephyr --xephyr-screen=640x480 fire‐
2065 fox
2066
2067
2069 Audit feature allows the user to point out gaps in security profiles.
2070 The implementation replaces the program to be sandboxed with a test
2071 program. By default, we use faudit program distributed with Firejail. A
2072 custom test program can also be supplied by the user. Examples:
2073
2074 Running the default audit program:
2075 $ firejail --audit transmission-gtk
2076
2077 Running a custom audit program:
2078 $ firejail --audit=~/sandbox-test transmission-gtk
2079
2080 In the examples above, the sandbox configures transmission-gtk profile
2081 and starts the test program. The real program, transmission-gtk, will
2082 not be started.
2083
2084 You can also audit a specific profile without specifying a program.
2085 $ firejail --audit --profile=/etc/firejail/zoom.profile
2086
2087 Limitations: audit feature is not implemented for --x11 commands.
2088
2089
2091 A symbolic link to /usr/bin/firejail under the name of a program, will
2092 start the program in Firejail sandbox. The symbolic link should be
2093 placed in the first $PATH position. On most systems, a good place is
2094 /usr/local/bin directory. Example:
2095
2096 Make a firefox symlink to /usr/bin/firejail:
2097
2098 $ sudo ln -s /usr/bin/firejail /usr/local/bin/firefox
2099
2100 Verify $PATH
2101
2102 $ which -a firefox
2103 /usr/local/bin/firefox
2104 /usr/bin/firefox
2105
2106 Starting firefox in this moment, automatically invokes “firejail
2107 firefox”.
2108
2109 This works for clicking on desktop environment icons, menus etc. Use
2110 "firejail --tree" to verify the program is sandboxed.
2111
2112 $ firejail --tree
2113 1189:netblue:firejail firefox
2114 1190:netblue:firejail firefox
2115 1220:netblue:/bin/sh -c "/usr/lib/firefox/firefox"
2116 1221:netblue:/usr/lib/firefox/firefox
2117
2118 We provide a tool that automates all this integration, please see
2119 firecfg(1) for more details.
2120
2121
2123 firejail
2124 Sandbox a regular shell session.
2125
2126 firejail firefox
2127 Start Mozilla Firefox.
2128
2129 firejail --debug firefox
2130 Debug Firefox sandbox.
2131
2132 firejail --private firefox
2133 Start Firefox with a new, empty home directory.
2134
2135 firejail --net=none vlc
2136 Start VLC in an unconnected network namespace.
2137
2138 firejail --net=eth0 firefox
2139 Start Firefox in a new network namespace. An IP address is as‐
2140 signed automatically.
2141
2142 firejail --net=br0 --ip=10.10.20.5 --net=br1 --net=br2
2143 Start a shell session in a new network namespace and connect it
2144 to br0, br1, and br2 host bridge devices. IP addresses are as‐
2145 signed automatically for the interfaces connected to br1 and b2
2146
2147 firejail --list
2148 List all sandboxed processes.
2149
2150
2152 Globbing is the operation that expands a wildcard pattern into the
2153 list of pathnames matching the pattern. This pattern is matched
2154 at firejail start, and is NOT UPDATED at runtime. Files match‐
2155 ing a blacklist, but created after firejail start will be acces‐
2156 sible within the jail. Matching is defined by:
2157
2158 - '?' matches any character
2159 - '*' matches any string
2160 - '[' denotes a range of characters
2161
2162 The globbing feature is implemented using glibc glob command. For
2163 more information on the wildcard syntax see man 7 glob.
2164
2165
2166 The following command line options are supported: --blacklist,
2167 --private-bin, --noexec, --read-only, --read-write, --tmpfs, and
2168 --whitelist.
2169
2170
2171 Examples:
2172
2173 $ firejail --private-bin=sh,bash,python*
2174 $ firejail --blacklist=~/dir[1234]
2175 $ firejail --read-only=~/dir[1-4]
2176
2177
2179 These features allow the user to inspect the filesystem container of an
2180 existing sandbox and transfer files between the container and the host
2181 filesystem.
2182
2183
2184 --cat=name|pid filename
2185 Write content of a container file to standard out. The container
2186 is specified by name or PID. If standard out is a terminal, all
2187 ASCII control characters except new line and horizontal tab are
2188 replaced.
2189
2190
2191 --get=name|pid filename
2192 Retrieve the container file and store it on the host in the cur‐
2193 rent working directory. The container is specified by name or
2194 PID.
2195
2196
2197 --ls=name|pid dir_or_filename
2198 List container files. The container is specified by name or PID.
2199
2200
2201 --put=name|pid src-filename dest-filename
2202 Put src-filename in sandbox container. The container is speci‐
2203 fied by name or PID.
2204
2205
2206 Examples:
2207
2208 $ firejail --name=mybrowser --private firefox
2209
2210 $ firejail --ls=mybrowser ~/Downloads
2211 drwxr-xr-x netblue netblue 4096 .
2212 drwxr-xr-x netblue netblue 4096 ..
2213 -rw-r--r-- netblue netblue 7847 x11-x305.png
2214 -rw-r--r-- netblue netblue 6800 x11-x642.png
2215 -rw-r--r-- netblue netblue 34139 xpra-clipboard.png
2216
2217 $ firejail --get=mybrowser ~/Downloads/xpra-clipboard.png
2218
2219 $ firejail --put=mybrowser xpra-clipboard.png ~/Downloads/xpra-
2220 clipboard.png
2221
2222 $ firejail --cat=mybrowser ~/.bashrc
2223
2225 Option --list prints a list of all sandboxes. The format for each
2226 process entry is as follows:
2227
2228 PID:USER:Sandbox Name:Command
2229
2230 Option --tree prints the tree of processes running in the sandbox. The
2231 format for each process entry is as follows:
2232
2233 PID:USER:Sandbox Name:Command
2234
2235 Option --top is similar to the UNIX top command, however it applies
2236 only to sandboxes.
2237
2238 Option --netstats prints network statistics for active sandboxes in‐
2239 stalling new network namespaces.
2240
2241 Listed below are the available fields (columns) in alphabetical order
2242 for --top and --netstats options:
2243
2244
2245 Command
2246 Command used to start the sandbox.
2247
2248 CPU% CPU usage, the sandbox share of the elapsed CPU time since the
2249 last screen update
2250
2251 PID Unique process ID for the task controlling the sandbox.
2252
2253 Prcs Number of processes running in sandbox, including the control‐
2254 ling process.
2255
2256 RES Resident Memory Size (KiB), sandbox non-swapped physical memory.
2257 It is a sum of the RES values for all processes running in the
2258 sandbox.
2259
2260 RX(KB/s)
2261 Network receive speed.
2262
2263 Sandbox Name
2264 The name of the sandbox, if any.
2265
2266 SHR Shared Memory Size (KiB), it reflects memory shared with other
2267 processes. It is a sum of the SHR values for all processes run‐
2268 ning in the sandbox, including the controlling process.
2269
2270 TX(KB/s)
2271 Network transmit speed.
2272
2273 Uptime Sandbox running time in hours:minutes:seconds format.
2274
2275 USER The owner of the sandbox.
2276
2277
2279 To configure a restricted shell, replace /bin/bash with /usr/bin/fire‐
2280 jail in /etc/passwd file for each user that needs to be restricted. Al‐
2281 ternatively, you can specify /usr/bin/firejail in adduser command:
2282
2283 adduser --shell /usr/bin/firejail username
2284
2285 Additional arguments passed to firejail executable upon login are de‐
2286 clared in /etc/firejail/login.users file.
2287
2288
2290 Several command line options can be passed to the program using profile
2291 files. Firejail chooses the profile file as follows:
2292
2293 1. If a profile file is provided by the user with --profile=FILE op‐
2294 tion, the profile FILE is loaded. If a profile name is given, it is
2295 searched for first in the ~/.config/firejail directory and if not found
2296 then in /etc/firejail directory. Profile names do not include the
2297 .profile suffix. If there is a file with the same name as the given
2298 profile name, it will be used instead of doing the profile search. To
2299 force a profile search, prefix the profile name with a colon (:), eg.
2300 --profile=:PROFILE_NAME. Example:
2301
2302 $ firejail --profile=/home/netblue/icecat.profile icecat
2303 Reading profile /home/netblue/icecat.profile
2304 [...]
2305
2306
2307 $ firejail --profile=icecat icecat-wrapper.sh
2308 Reading profile /etc/firejail/icecat.profile
2309 [...]
2310
2311 2. If a profile file with the same name as the application is present
2312 in ~/.config/firejail directory or in /etc/firejail, the profile is
2313 loaded. ~/.config/firejail takes precedence over /etc/firejail. Exam‐
2314 ple:
2315
2316 $ firejail icecat
2317 Command name #icecat#
2318 Found icecat profile in /home/netblue/.config/firejail directory
2319 Reading profile /home/netblue/.config/firejail/icecat.profile
2320 [...]
2321
2322 3. Use default.profile file if the sandbox is started by a regular
2323 user, or server.profile file if the sandbox is started by root. Fire‐
2324 jail looks for these files in ~/.config/firejail directory, followed by
2325 /etc/firejail directory. To disable default profile loading, use --no‐
2326 profile command option. Example:
2327
2328 $ firejail
2329 Reading profile /etc/firejail/default.profile
2330 Parent pid 8553, child pid 8554
2331 Child process initialized
2332 [...]
2333
2334 $ firejail --noprofile
2335 Parent pid 8553, child pid 8554
2336 Child process initialized
2337 [...]
2338
2339 See man 5 firejail-profile for profile file syntax information.
2340
2342 Network bandwidth is an expensive resource shared among all sandboxes
2343 running on a system. Traffic shaping allows the user to increase net‐
2344 work performance by controlling the amount of data that flows into and
2345 out of the sandboxes.
2346
2347 Firejail implements a simple rate-limiting shaper based on Linux com‐
2348 mand tc. The shaper works at sandbox level, and can be used only for
2349 sandboxes configured with new network namespaces.
2350
2351 Set rate-limits:
2352
2353 $ firejail --bandwidth=name|pid set network download upload
2354
2355 Clear rate-limits:
2356
2357 $ firejail --bandwidth=name|pid clear network
2358
2359 Status:
2360
2361 $ firejail --bandwidth=name|pid status
2362
2363 where:
2364 name - sandbox name
2365 pid - sandbox pid
2366 network - network interface as used by --net option
2367 download - download speed in KB/s (kilobyte per second)
2368 upload - upload speed in KB/s (kilobyte per second)
2369
2370 Example:
2371 $ firejail --name=mybrowser --net=eth0 firefox &
2372 $ firejail --bandwidth=mybrowser set eth0 80 20
2373 $ firejail --bandwidth=mybrowser status
2374 $ firejail --bandwidth=mybrowser clear eth0
2375
2377 This program is free software; you can redistribute it and/or modify it
2378 under the terms of the GNU General Public License as published by the
2379 Free Software Foundation; either version 2 of the License, or (at your
2380 option) any later version.
2381
2382 Homepage: https://firejail.wordpress.com
2383
2385 firemon(1), firecfg(1), firejail-profile(5), firejail-login(5), fire‐
2386 jail-users(5), ⟨https://github.com/netblue30/firejail/wiki⟩,
2387 ⟨https://github.com/netblue30/firejail⟩
2388
2389
2390
23910.9.64.4 Feb 2021 FIREJAIL(1)