firejail-profile man page

profile — Security profile file syntax for Firejail

Usage

firejail --profile=filename.profile

firejail --profile=profile_name

Description

Several command line options can be passed to the program using profile files. Firejail chooses the profile file as follows:

1. If a profile file is provided by the user with --profile option, the profile file is loaded. If a profile name is given, it is searched for first in the ~/.config/firejail directory and if not found then in  /etc/firejail directory. Profile names do not include the .profile suffix. Example:

$ firejail --profile=/home/netblue/icecat.profile icecat
Reading profile /home/netblue/icecat.profile
[...]

$ firejail --profile=icecat icecat-wrapper.sh
Reading profile /etc/firejail/icecat.profile
[...]

2. If a profile file with the same name as the application is present in ~/.config/firejail directory or in /etc/firejail, the profile is loaded. ~/.config/firejail takes precedence over /etc/firejail. Example:

$ firejail icecat
Command name #icecat#
Found icecat profile in /home/netblue/.config/firejail directory
Reading profile /home/netblue/.config/firejail/icecat.profile
[...]

3. Use a default.profile file if the sandbox is started by a regular user, or a server.profile file if the sandbox is started by root. Firejail looks for these files in ~/.config/firejail directory, followed by /etc/firejail directory. To disable default profile loading, use --noprofile command option. Example:

$ firejail
Reading profile /etc/firejail/default.profile
Parent pid 8553, child pid 8554
Child process initialized
[...]

$ firejail --noprofile
Parent pid 8553, child pid 8554
Child process initialized
[...]

Scripting

Scripting commands:

File and directory names

File and directory names containing spaces are supported. The space character ' ' should not be escaped.

Example: "blacklist ~/My Virtual Machines"

# this is a comment
?CONDITIONAL: profile line

Conditionally add profile line.

Example: "?HAS_APPIMAGE: whitelist ${HOME}/special/appimage/dir"

This example will load the whitelist profile line only if the --appimage option has been specified on the command line.

Currently the only conditional supported is HAS_APPIMAGE.

The profile line may be any profile line that you would normally use in a profile except for "quiet" and "include" lines.

include other.profile

Include other.profile file.

Example: "include /etc/firejail/disable-common.inc"

The file name can be prefixed with a macro such as ${HOME} or ${CFG}. ${HOME} is expanded as user home directory, and ${CFG} is expanded as Firejail system configuration directory - in most cases /etc/firejail or /usr/local/etc/firejail.

Example: "include ${HOME}/myprofiles/profile1" will load "~/myprofiles/profile1" file.

Example: "include ${CFG}/firefox.profile" will load "/etc/firejail/firefox.profile" file.

The file name may also be just the name without the leading directory components.  In this case, first the user config directory (${HOME}/.config/firejail) is searched for the file name and if not found then the system configuration directory is search for the file name.  Note: Unlike the --profile option which takes a profile name without the '.profile' suffix, include must be given the full file name.

Example: "include firefox.profile" will load "${HOME}/.config/firejail/firefox.profile" file and if it does not exist "${CFG}/firefox.profile" will be loaded.

System configuration files in ${CFG} are overwritten during software installation. Persistent configuration at system level is handled in ".local" files. For every profile file in ${CFG} directory, the user can create a corresponding .local file storing modifications to the persistent configuration. Persistent .local files are included at the start of regular profile files.

noblacklist file_name

If the file name matches file_name, the file will not be blacklisted in any blacklist commands that follow.

Example: "noblacklist ${HOME}/.mozilla"

nowhitelist file_name

If the file name matches file_name, the file will not be whitelisted in any whitelist commands that follow.

Example: "nowhitelist ~/.config"

ignore

Ignore command.

Example: "ignore seccomp"
Example: "ignore net ehh0"

quiet

Disable Firejail's output. This should be the first uncommented command in the profile file.

Example: "quiet"

Filesystem

These profile entries define a chroot filesystem built on top of the existing host filesystem. Each line describes a file element that is removed from the filesystem (blacklist), a read-only file or directory (read-only), a tmpfs mounted on top of an existing directory (tmpfs), or mount-bind a directory  or file on top of another directory or file (bind). Use private to set private mode. File globbing is supported, and PATH and HOME directories are searched. Examples:

blacklist file_or_directory

Blacklist directory or file. Examples:

blacklist /usr/bin
blacklist /usr/bin/gcc*
blacklist ${PATH}/ifconfig
blacklist ${HOME}/.ssh

blacklist-nolog file_or_directory

When --tracelog flag is set, blacklisting generates syslog messages if the sandbox tries to access the file or directory. blacklist-nolog command disables syslog messages for this particular file or directory. Examples:

blacklist-nolog /usr/bin
blacklist-nolog /usr/bin/gcc*

bind directory1,directory2

Mount-bind directory1 on top of directory2. This option is only available when running as root.

bind file1,file2

Mount-bind file1 on top of file2. This option is only available when running as root.

disable-mnt

Disable /mnt, /media, /run/mount and /run/media access.

keep-var-tmp

/var/tmp directory is untouched.

mkdir directory

Create a directory in user home or under /tmp before the sandbox is started. The directory is created if it doesn't already exist.

Use this command for whitelisted directories you need to preserve when the sandbox is closed. Without it, the application will create the directory, and the directory will be deleted when the sandbox is closed. Subdirectories are recursively created. Example from firefox profile:

mkdir ~/.mozilla
whitelist ~/.mozilla
mkdir ~/.cache/mozilla/firefox
whitelist ~/.cache/mozilla/firefox

mkfile file

Similar to mkdir, this command creates a file in user home or under /tmp before the sandbox is started. The file is created if it doesn't already exist.

noexec file_or_directory

Remount the file or the directory noexec, nodev and nosuid.

overlay

Mount  a  filesystem  overlay  on top of the current filesystem. The overlay is stored in $HOME/.firejail/<PID>  directory.

overlay-named name

Mount  a  filesystem  overlay  on top of the current filesystem. The overlay is stored in $HOME/.firejail/name  directory.

overlay-tmpfs

Mount  a  filesystem  overlay  on top of the current filesystem. All filesystem  modifications are discarded when the sandbox is closed.

private

Mount new /root and /home/user directories in temporary filesystems. All modifications are discarded when the sandbox is closed.

private directory

Use directory as user home.

private-home file,directory

Build a new user home in a temporary filesystem, and copy the files and directories in the list in the new home. All modifications are discarded when the sandbox is closed.

private-cache

Mount an empty temporary filesystem on top of the .cache directory in user home. All modifications are discarded when the sandbox is closed.

private-bin file,file

Build a new /bin in a temporary filesystem, and copy the programs in the list. The same directory is also bind-mounted over /sbin, /usr/bin and /usr/sbin.

private-dev

Create a new /dev directory. Only disc, dri, null, full, zero, tty, pts, ptmx, random, snd, urandom, video, log and shm devices are available.

keep-dev-shm

/dev/shm directory is untouched (even with private-dev).

private-etc file,directory

Build a new /etc in a temporary filesystem, and copy the files and directories in the list. All modifications are discarded when the sandbox is closed.

private-lib file,directory

Build a new /lib directory and bring in the libraries required by the application to run. This feature is still under development, see man 1 firejail for some examples.

private-opt file,directory

Build a new /optin a temporary filesystem, and copy the files and directories in the list. All modifications are discarded when the sandbox is closed.

private-srv file,directory

Build a new /srv in a temporary filesystem, and copy the files and directories in the list. All modifications are discarded when the sandbox is closed.

private-tmp

Mount an empty temporary filesystem on top of /tmp directory whitelisting /tmp/.X11-unix.

read-only file_or_directory

Make directory or file read-only.

read-write file_or_directory

Make directory or file read-write.

tmpfs directory

Mount an empty tmpfs filesystem on top of directory. This option is available only when running the sandbox as root.

tracelog

Blacklist violations logged to syslog.

whitelist file_or_directory

Whitelist directory or file. A temporary file system is mounted on the top directory, and the whitelisted files are mount-binded inside. Modifications to whitelisted files are persistent, everything else is discarded when the sandbox is closed. The top directory could be user home, /dev, /etc, /media, /mnt, /opt, /srv, /sys/module, /usr/share, /var, and /tmp.

Symbolic link handling: with the exception of user home, both the link and the real file should be in the same top directory. For user home, both the link and the real file should be owned by the user.

writable-etc

Mount /etc directory read-write.

writable-run-user

Disable the default blacklisting of run/user/$UID/systemd and /run/user/$UID/gnupg.

writable-var

Mount /var directory read-write.

writable-var-log

Use the real /var/log directory, not a clone. By default, a tmpfs is mounted on top of /var/log directory, and a skeleton filesystem is created based on the original /var/log.

Security filters

The following security filters are currently implemented:

apparmor

Enable AppArmor confinement.

caps

Enable default Linux capabilities filter.

caps.drop all

Blacklist all Linux capabilities.

caps.drop capability,capability,capability

Blacklist given Linux capabilities.

caps.keep capability,capability,capability

Whitelist given Linux capabilities.

protocol protocol1,protocol2,protocol3

Enable protocol filter. The filter is based on seccomp and  checks the first argument to socket system call. Recognized values: unix, inet, inet6, netlink and packet.

seccomp

Enable seccomp filter and blacklist the syscalls in the default list. See man 1 firejail for more details.

seccomp syscall,syscall,syscall

Enable seccomp filter and blacklist the system calls in the list on top of default seccomp filter.

seccomp.block-secondary

Enable seccomp filter and filter system call architectures so that only the native architecture is allowed.

seccomp.drop syscall,syscall,syscall

Enable seccomp filter and blacklist  the system calls in the list.

seccomp.keep syscall,syscall,syscall

Enable seccomp filter and whitelist the system calls in the list.

memory-deny-write-execute

Install a seccomp filter to block attempts to create memory mappings that are both writable and executable, to change mappings to be executable or to create executable shared memory.

nonewprivs

Sets the NO_NEW_PRIVS prctl.  This ensures that child processes cannot acquire new privileges using execve(2);  in particular, this means that calling a suid binary (or one with file capabilities) does not result in an increase of privilege.

noroot

Use this command  to enable an user namespace. The namespace has only one user, the current user. There is no root account (uid 0) defined in the namespace.

x11

Enable X11 sandboxing.

x11 none

Blacklist /tmp/.X11-unix directory, ${HOME}/.Xauthority and file specified in ${XAUTHORITY} environment variable. Remove DISPLAY and XAUTHORITY environment variables. Stop with error message if X11 abstract socket will be accessible in jail.

x11 xephyr

Enable X11 sandboxing with Xephyr server.

x11 xorg

Enable X11 sandboxing with X11 security extension.

x11 xpra

Enable X11 sandboxing with Xpra server.

x11 xvfb

Enable X11 sandboxing with Xvfb server.

xephyr-screen WIDTHxHEIGHT

Set screen size for x11 xephyr. This command should be included in the profile file before x11 xephyr command.

Example:

xephyr-screen 640x480
x11 xephyr

Resource limits, CPU affinity, Control Groups

These profile entries define the limits on system resources (rlimits) for the processes inside the sandbox. The limits can be modified inside the sandbox using the regular ulimit command. cpu command configures the CPU cores available, and cgroup command place the sandbox in an existing control group.

Examples:

rlimit-as 123456789012

Set the maximum size of the process's virtual memory to 123456789012 bytes.

rlimit-cpu 123

Set the maximum CPU time in seconds.

rlimit-fsize 1024

Set the maximum file size that can be created by a process to 1024 bytes.

rlimit-nproc 1000

Set the maximum number of processes that can be created for the real user ID of the calling process to 1000.

rlimit-nofile 500

Set the maximum number of files that can be opened by a process to 500.

rlimit-sigpending 200

Set the maximum number of processes that can be created for the real user ID of the calling process to 200.

cpu 0,1,2

Use only CPU cores 0, 1 and 2.

nice -5

Set a nice value of -5 to all processes running inside the sandbox.

cgroup /sys/fs/cgroup/g1/tasks

The sandbox is placed in g1 control group.

timeout hh:mm:ss

Kill the sandbox automatically after the time has elapsed. The time is specified in hours/minutes/seconds format.

User Environment

allusers

All user home directories are visible inside the sandbox. By default, only current user home directory is visible.

name sandboxname

Set sandbox name. Example:

name browser

env name=value

Set environment variable. Examples:

env LD_LIBRARY_PATH=/opt/test/lib
env CFLAGS="-W -Wall -Werror"

nodvd

Disable DVD and audio CD devices.

nogroups

Disable supplementary user groups

shell none

Run the program directly, without a shell.

ipc-namespace

Enable IPC namespace.

nodbus

Disable D-Bus access. Only the regular UNIX socket is handled by this command. To disable the abstract socket, you would need to request a new network namespace using the net command. Another option is to remove unix from protocol set.

nosound

Disable sound system.

noautopulse

Disable automatic ~/.config/pulse init, for complex setups such as remote pulse servers or non-standard socket paths.

notv

Disable DVB (Digital Video Broadcasting) TV devices.

nou2f

Disable U2F devices.

novideo

Disable video devices.

no3d

Disable 3D hardware acceleration.

Networking

Networking features available in profile files.

defaultgw address

Use this address as default gateway in the new network namespace.

dns address

Set a DNS server for the sandbox. Up to three DNS servers can be defined.

hostname name

Set a hostname for the sandbox.

hosts-file file

Use file as /etc/hosts.

ip address

Assign IP addresses to the last network interface defined by a net command. A default gateway is assigned by default.

Example:
net eth0
ip 10.10.20.56

ip none

No IP address and no default gateway are configured for the last interface defined by a net command. Use this option in case you intend to start an external DHCP client in the sandbox.

Example:
net eth0
ip none

ip6 address

Assign IPv6 addresses to the last network interface defined by a net command.

Example:
net eth0
ip6 2001:0db8:0:f101::1/64

iprange address,address

Assign  an  IP address in the provided range to the last network interface defined by  a  net command.  A  default  gateway  is assigned by default.

Example:

net eth0
iprange 192.168.1.150,192.168.1.160

mac address

Assign MAC addresses to the last network interface defined by a net command.

machine-id

Spoof id number in /etc/machine-id file - a new random id is generated inside the sandbox.

mtu number

Assign a MTU value to the last network interface defined by a net command.

netfilter

If a new network namespace is created, enabled default network filter.

netfilter filename

If a new network namespace is created, enabled the network filter in filename.

net bridge_interface

Enable a new network namespace and connect it to this bridge interface. Unless specified with option --ip and --defaultgw, an IP address and a default gateway will be assigned automatically to the sandbox. The IP address is verified using ARP before assignment. The address configured as default gateway is the bridge device IP address. Up to four --net bridge devices can be defined. Mixing bridge and macvlan devices is allowed.

net ethernet_interface|wireless_interface

Enable a new network namespace and connect it to this ethernet interface using the standard Linux macvlan or ipvlan driver. Unless specified with option --ip and --defaultgw, an IP address and a default gateway will be assigned automatically to the sandbox. The IP address is verified using ARP before assignment. The address configured as default gateway is the default gateway of the host. Up to four --net devices can be defined. Mixing bridge and macvlan devices is allowed.

net tap_interface

Enable a new network namespace and connect it to this ethernet tap interface using the standard Linux macvlan driver.  If the tap interface is not configured, the sandbox will not try to configure the interface inside the sandbox. Please use ip, netmask and defaultgw to specify the configuration.

net none

Enable a new, unconnected network namespace. The only interface available in the new namespace is a new loopback interface (lo). Use this option to deny network access to programs that don't really need network access.

netmask address

Use this option when you want to assign an IP address in a new namespace and the parent interface specified by --net is not configured. An IP address and a default gateway address also have to be added.

veth-name name

Use this name for the interface connected to the bridge for --net=bridge_interface commands, instead of the default one.

Other

join-or-start sandboxname

Join the sandbox identified by name or start a new one. Same as "firejail --join=sandboxname" command if sandbox with specified name exists, otherwise same as "name sandboxname".

Files

/etc/firejail/filename.profile, $HOME/.config/firejail/filename.profile

License

Firejail is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

Homepage: https://firejail.wordpress.com

See Also

firejail(1), firemon(1), firecfg(1), firejail-login(5) firejail-users(5)

Referenced By

firecfg(1), firejail(1), firejail-login(5), firejail-users(5), firemon(1).

Jul 2019 0.9.57 firejail profiles man page