security-misc/usr/bin/pkexec.security-misc
Patrick Schleizer 649ec5dfa1
pkexec wrapper: fix gdebi / synaptic
but at cost of checking for passwordless sudo /etc/suders /etc/sudoers.d
exceptions.

http://forums.whonix.org/t/cannot-use-pkexec/8129/53
2020-02-29 04:59:56 -05:00

133 lines
3.9 KiB
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#!/bin/bash
## Copyright (C) 2019 - 2019 ENCRYPTED SUPPORT LP <adrelanos@riseup.net>
## See the file COPYING for copying conditions.
## Redirect calls for pkexec to lxqt-sudo because pkexec is incompatible with
## hidepid.
## * https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=860040
## * https://forums.whonix.org/t/cannot-use-pkexec/8129
set -e
my_real_path="$(realpath "$0")" || true
identifier="$my_real_path wrapper"
exec > >(systemd-cat --identifier="$identifier output by program:") 2>&1
log_to_journal() {
echo "$@" | systemd-cat --identifier="$identifier output by wrapper:" || true
}
log_to_journal "$0 $@"
log_to_journal "DISPLAY: '$DISPLAY'"
my_pstree="$(pstree -p $$)" || true
log_to_journal "my_pstree: '$my_pstree'"
## If hidepid is not in use, just use pkexec normally.
if ! mount | grep "/proc" | grep "hidepid=2" &>/dev/null ; then
pkexec.security-misc-orig "$@"
exit $?
fi
switch_user=false
original_args="$@"
## Thanks to:
## http://mywiki.wooledge.org/BashFAQ/035
while :
do
case $1 in
## Should show 'pkexec --version' or fail?
--version)
shift
pkexec.security-misc-orig "$original_args"
exit $?
;;
## Should show 'pkexec --help' or fail?
--help)
shift
pkexec.security-misc-orig "$original_args"
exit $?
;;
## Drop --disable-internal-agent as not needed and breaking both,
## lxqt-sudo and sudo.
--disable-internal-agent)
shift
;;
--user)
## lxqt-sudo does not support "--user".
## We should not make this wrapper run something as root which
## is supposed to run under a different user. Try using
## "sudo -A --user user --set-home" instead.
user_pkexec_wrapper="$2"
if [ "$user_pkexec_wrapper" = "" ]; then
shift
else
shift 2
fi
switch_user=true
maybe_switch_to_user="--user $user_pkexec_wrapper"
;;
--)
shift
break
;;
*)
break
;;
esac
done
## If there are input files (for example) that follow the options, they
## will remain in the "$@" positional parameters.
if [ "$PKEXEC_UID" = "" ]; then
if [ ! "$user_pkexec_wrapper" = "" ]; then
PKEXEC_UID="$user_pkexec_wrapper"
elif [ ! "$SUDO_USER" = "" ]; then
PKEXEC_UID="$SUDO_USER"
else
PKEXEC_UID="$(whoami)"
fi
fi
export PKEXEC_UID
if [[ "$@" = "" ]]; then
## Call original pkexec in case there are no arguments.
pkexec.security-misc-orig $original_args
exit $?
fi
exit_code=0
## lxqt-sudo does not check /etc/sudoers / /etc/sudoers.d exceptions.
## Therefore use 'sudo -l' to see if there is any already existing sudoers exception.
## Did not work. 'sudo -l' will always exit with exit code '0'.
# if sudo -l --non-interactive $maybe_switch_to_user --set-home PKEXEC_UID="$PKEXEC_UID" "$@" ; then
# log_to_journal "sudoers exception: yes"
# sudo --non-interactive $maybe_switch_to_user --set-home PKEXEC_UID="$PKEXEC_UID" "$@" || { exit_code=$? ; true; };
# log_to_journal "sudo --user | exit_code: '$exit_code'"
# exit "$exit_code"
# fi
#
# log_to_journal "sudoers exception: no"
if [ "$switch_user" = "true" ]; then
## 'sudo --user user' clears environment variables such as PATH.
lxqt-sudo sudo $maybe_switch_to_user --set-home PKEXEC_UID="$PKEXEC_UID" "$@" || { exit_code=$? ; true; };
else
## set PATH same as root
## This is required for gdebi.
## REVIEW: is it ok that users can find out the PATH setting of root?
## lxqt-sudo does not clear environment variable PATH.
PATH="$(sudo --non-interactive /usr/lib/security-misc/echo-path)"
export PATH
lxqt-sudo "$@" || { exit_code=$? ; true; };
fi
log_to_journal "exit_code: '$exit_code'"
exit "$exit_code"