security-misc/etc/permission-hardening.d/30_default.conf

## Copyright (C) 2012 - 2020 ENCRYPTED SUPPORT LP <adrelanos@riseup.net>
## See the file COPYING for copying conditions.

## Please use "/etc/permission-hardening.d/20_user.conf" or
## "/usr/local/etc/permission-hardening.d/20_user.conf" for your custom
## configuration. When security-misc is updated, this file may be overwritten.

## File permission hardening.
##
## Syntax:
## [filename] [mode] [owner] [group] [capability]
##
## To remove all SUID/SGID binaries in a directory, you can use the "nosuid"
## argument.

## TODO: white spaces inside file name untested and probably will not work.

######################################################################
# SUID disablewhitelist
######################################################################

## disablewhitelist disables below (or in lexically higher) files
## exactwhitelist and matchwhitelist. Add these here (discouraged) or better
## in file "/etc/permission-hardening.d/20_user.conf".

## For example, if you are not using SELinux the following might make sense to
## enable. TODO: research
#/utempter/utempter disablewhitelist

## If you are not going to use AppImages such as electrum Bitcoin wallet.
#/fusermount disablewhitelist

######################################################################
# SUID exact match whitelist
######################################################################

/usr/bin/sudo exactwhitelist
/bin/sudo exactwhitelist
/usr/bin/bwrap exactwhitelist
/bin/bwrap exactwhitelist
/usr/lib/spice-gtk/spice-client-glib-usb-acl-helper exactwhitelist
/usr/lib/chromium/chrome-sandbox exactwhitelist

/usr/bin/pkexec exactwhitelist
/usr/bin/pkexec.security-misc-orig exactwhitelist

## https://forums.whonix.org/t/disable-suid-binaries/7706/61
## Protect from 'chmod -x' (and SUID removal).
## SUID will be removed below in separate step.
/bin/mount exactwhitelist
/usr/bin/mount exactwhitelist

## There is a controversy about firejail but those who choose to install it
## should be able to use it.
## https://www.whonix.org/wiki/Dev/Firejail#Security
/usr/bin/firejail exactwhitelist

## In case you need to use 'su'. See also:
## https://www.whonix.org/wiki/root#su
#/bin/su exactwhitelist
#/usr/bin/su exactwhitelist

######################################################################
# SUID exact match whitelist
######################################################################

## https://manpages.debian.org/buster/xserver-xorg-legacy/Xorg.wrap.1.en.html
## https://lwn.net/Articles/590315/
## http://forums.whonix.org/t/permission-hardening/8655/25
#/usr/lib/xorg/Xorg.wrap whitelist

######################################################################
# SUID regex match whitelist - research required
######################################################################

/usr/lib/virtualbox/ matchwhitelist

## https://github.com/QubesOS/qubes-core-agent-linux/blob/master/qubes-rpc/qfile-unpacker.c
## match both:
#/usr/lib/qubes/qfile-unpacker whitelist
#/lib/qubes/qfile-unpacker
/qubes/qfile-unpacker matchwhitelist

## match both:
#/usr/lib/policykit-1/polkit-agent-helper-1 matchwhitelist
#/lib/policykit-1/polkit-agent-helper-1
polkit-agent-helper-1 matchwhitelist

######################################################################
# SUID regex match whitelist
######################################################################

dbus-daemon-launch-helper matchwhitelist
/utempter/utempter matchwhitelist

## required for AppImages such as electrum Bitcoin wallet
## https://forums.whonix.org/t/disable-suid-binaries/7706/57
/fusermount matchwhitelist

######################################################################
# Permission Hardening
######################################################################

## Remove SUID from 'mount' but keep executable.
## https://forums.whonix.org/t/disable-suid-binaries/7706/61
/bin/mount 745 root root
/usr/bin/mount 745 root root

/home/ 0755 root root
/home/user/ 0700 user user
/root/ 0700 root root
/boot/ 0700 root root
/etc/permission-hardening.d 0600 root root
/usr/local/etc/permission-hardening.d 0600 root root
/lib/modules/ 0700 root root

######################################################################
# SUID/SGID Removal
######################################################################

## Remove all SUID/SGID binaries/libraries.

/bin/ nosuid
/usr/bin/ nosuid
/usr/local/bin/ nosuid
/sbin/ nosuid
/usr/sbin/ nosuid
/usr/local/sbin/ nosuid
/lib/ nosuid
/lib32/ nosuid
/lib64/ nosuid
/usr/lib/ nosuid
/usr/lib32/ nosuid
/usr/lib64/ nosuid
/usr/local/lib/ nosuid
/usr/local/lib32/ nosuid
/usr/local/lib64/ nosuid

######################################################################
# Capability Removal
######################################################################

## Ping doesn't work with Tor anyway so its capabilities are removed to
## reduce attack surface.
## anon-apps-config does this.
#/bin/ping 0744 root root none

## TODO: research
#/usr/lib/x86_64-linux-gnu/gstreamer1.0/grstreamer-1.0/gst-ptp-helper 0744 root root none