mirror of
https://github.com/Kicksecure/security-misc.git
synced 2024-12-12 12:04:24 -05:00
701 lines
24 KiB
Bash
Executable File
701 lines
24 KiB
Bash
Executable File
#!/bin/bash
|
|
|
|
## Copyright (C) 2012 - 2024 ENCRYPTED SUPPORT LP <adrelanos@whonix.org>
|
|
## See the file COPYING for copying conditions.
|
|
|
|
## https://forums.whonix.org/t/disable-suid-binaries/7706
|
|
## https://forums.whonix.org/t/re-mount-home-and-other-with-noexec-and-nosuid-among-other-useful-mount-options-for-better-security/7707
|
|
|
|
set -o errexit -o nounset -o pipefail
|
|
|
|
exit_code=0
|
|
store_dir="/var/lib/permission-hardener"
|
|
dpkg_admindir_parameter_existing_mode="--admindir ${store_dir}/existing_mode"
|
|
dpkg_admindir_parameter_new_mode="--admindir ${store_dir}/new_mode"
|
|
|
|
log_level=notice
|
|
# shellcheck disable=SC1091
|
|
source /usr/libexec/helper-scripts/log_run_die.sh
|
|
|
|
echo_wrapper_ignore() {
|
|
if test "${1}" = "verbose"; then
|
|
shift
|
|
log notice "Run: $*"
|
|
else
|
|
shift
|
|
fi
|
|
"$@" 2>/dev/null || true
|
|
}
|
|
|
|
echo_wrapper_audit() {
|
|
if test "${1}" = "verbose"; then
|
|
shift
|
|
log notice "Run: $*"
|
|
else
|
|
shift
|
|
fi
|
|
return_code=0
|
|
"$@" ||
|
|
{
|
|
return_code="$?"
|
|
exit_code=203
|
|
log error "Command '$*' failed with exit code '${return_code}'! calling function name: '${FUNCNAME[1]}'" >&2
|
|
}
|
|
}
|
|
|
|
make_store_dir(){
|
|
mkdir --parents "${store_dir}/private"
|
|
mkdir --parents "${store_dir}/existing_mode"
|
|
mkdir --parents "${store_dir}/new_mode"
|
|
}
|
|
|
|
sanity_tests() {
|
|
echo_wrapper_audit silent which \
|
|
capsh getcap setcap stat find dpkg-statoverride getent xargs grep 1>/dev/null
|
|
}
|
|
|
|
add_nosuid_statoverride_entry() {
|
|
local fso_to_process
|
|
fso_to_process="${fso}"
|
|
local should_be_counter
|
|
should_be_counter=0
|
|
local counter_actual
|
|
counter_actual=0
|
|
|
|
local dummy_line
|
|
while IFS="" read -r -d "" dummy_line; do
|
|
log info "Test would parse line: '${dummy_line}'"
|
|
should_be_counter=$((should_be_counter + 1))
|
|
done < <(find "${fso_to_process}" -perm /u=s,g=s -print0)
|
|
|
|
local line
|
|
while IFS="" read -r -d "" line; do
|
|
counter_actual="$((counter_actual + 1))"
|
|
|
|
local arr file_name file_name_from_stat existing_mode existing_owner existing_group stat_output
|
|
|
|
file_name="${line}"
|
|
|
|
if test -z "${file_name}"; then
|
|
log error "File name is empty in line: '${line}'" >&2
|
|
continue
|
|
fi
|
|
|
|
## Capture the stat output with fields separated by NUL characters.
|
|
## Delimiter at the end to avoid the last field to be interpreted as having a newline.
|
|
stat_output=$(stat -c '%n\0%a\0%U\0%G\0%' "${line}")
|
|
|
|
readarray -d '\0' -t arr <<< "${stat_output}"
|
|
|
|
if test "${#arr[@]}" = 0; then
|
|
log error "Line is empty. Stat output: '${stat_output}', line: '${line}'" >&2
|
|
continue
|
|
fi
|
|
|
|
file_name_from_stat="${arr[0]}"
|
|
existing_mode="${arr[1]}"
|
|
existing_owner="${arr[2]}"
|
|
existing_group="${arr[3]}"
|
|
|
|
if [ ! "$file_name" = "$file_name_from_stat" ]; then
|
|
log error "\
|
|
file_name is different from file_name_from_stat:
|
|
line: '${line}'
|
|
file_name '${file_name}'
|
|
file_name_from_stat: '${file_name_from_stat}'" >&2
|
|
continue
|
|
fi
|
|
|
|
if test -z "${existing_mode}"; then
|
|
log error "Existing mode is empty in line: '${line}'" >&2
|
|
continue
|
|
fi
|
|
if test -z "${existing_owner}"; then
|
|
log error "Existing owner is empty in line: '${line}'" >&2
|
|
continue
|
|
fi
|
|
if test -z "${existing_group}"; then
|
|
log error "Existing group is empty in line: '${line}'" >&2
|
|
continue
|
|
fi
|
|
|
|
## dpkg-statoverride: error: path may not contain newlines
|
|
if [[ "${file_name}" == *$'\n'* ]]; then
|
|
log warn "Skipping file name that contains newlines: '${file_name}'" >&2
|
|
continue
|
|
fi
|
|
|
|
## -h file True if file is a symbolic Link.
|
|
## -u file True if file has its set-user-id bit set.
|
|
## -g file True if file has its set-group-id bit set.
|
|
|
|
if test -h "${file_name}"; then
|
|
## https://forums.whonix.org/t/disable-suid-binaries/7706/14
|
|
log info "Skip symlink: '${file_name}'"
|
|
continue
|
|
fi
|
|
|
|
if test -d "${file_name}"; then
|
|
log info "Skip directory: '${file_name}'"
|
|
continue
|
|
fi
|
|
|
|
local setuid setuid_output setsgid setsgid_output
|
|
setuid=""
|
|
setuid_output=""
|
|
if test -u "${file_name}"; then
|
|
setuid=true
|
|
setuid_output="set-user-id"
|
|
fi
|
|
setsgid=""
|
|
setsgid_output=""
|
|
if test -g "${file_name}"; then
|
|
setsgid=true
|
|
setsgid_output="set-group-id"
|
|
fi
|
|
|
|
local setuid_or_setsgid
|
|
setuid_or_setsgid=""
|
|
if test "${setuid}" = "true" || test "${setsgid}" = "true"; then
|
|
setuid_or_setsgid=true
|
|
fi
|
|
if test -z "${setuid_or_setsgid}"; then
|
|
continue
|
|
fi
|
|
|
|
## Remove suid / gid and execute permission for 'group' and 'others'.
|
|
## Similar to: chmod og-ugx /path/to/filename
|
|
## Removing execution permission is useful to make binaries such as 'su'
|
|
## fail closed rather than fail open if suid was removed from these.
|
|
## Do not remove read access since no security benefit and easier to
|
|
## manually undo for users.
|
|
## Are there suid or sgid binaries which are still useful if suid / sgid
|
|
## has been removed from these?
|
|
new_mode="744"
|
|
|
|
local is_exact_whitelisted
|
|
is_exact_whitelisted=""
|
|
for white_list_entry in "${exact_white_list[@]:-}"; do
|
|
if test -z "${white_list_entry}"; then
|
|
continue
|
|
fi
|
|
if test "${file_name}" = "${white_list_entry}"; then
|
|
is_exact_whitelisted="true"
|
|
## Stop looping through the whitelist.
|
|
break
|
|
fi
|
|
done
|
|
|
|
local is_match_whitelisted
|
|
is_match_whitelisted=""
|
|
for matchwhite_list_entry in "${match_white_list[@]:-}"; do
|
|
if test -z "${matchwhite_list_entry}"; then
|
|
continue
|
|
fi
|
|
if echo "${file_name}" | grep --quiet --fixed-strings "${matchwhite_list_entry}"; then
|
|
is_match_whitelisted="true"
|
|
## Stop looping through the match_white_list.
|
|
break
|
|
fi
|
|
done
|
|
|
|
local is_disable_whitelisted
|
|
is_disable_whitelisted=""
|
|
for disablematch_list_entry in "${disable_white_list[@]:-}"; do
|
|
if test -z "${disablematch_list_entry}"; then
|
|
continue
|
|
fi
|
|
if echo "${file_name}" | grep --quiet --fixed-strings "${disablematch_list_entry}"; then
|
|
is_disable_whitelisted="true"
|
|
## Stop looping through the disablewhitelist.
|
|
break
|
|
fi
|
|
done
|
|
|
|
local clean_output_prefix clean_output
|
|
clean_output_prefix="Managing (S|G)UID of line:"
|
|
clean_output="setuid='${setuid_output}' setgid='${setsgid_output}' existing_mode='${existing_mode}' new_mode='${new_mode}' file='${file_name}'"
|
|
if test "${whitelists_disable_all:-}" = "true"; then
|
|
log info "${clean_output_prefix} whitelists_disable_all=true ${clean_output}"
|
|
elif test "${is_disable_whitelisted}" = "true"; then
|
|
log info "${clean_output_prefix} is_disable_whitelisted=true ${clean_output}"
|
|
else
|
|
if test "${is_exact_whitelisted}" = "true"; then
|
|
log info "${clean_output_prefix} is_exact_whitelisted=true ${clean_output}"
|
|
continue
|
|
fi
|
|
if test "${is_match_whitelisted}" = "true"; then
|
|
log info "${clean_output_prefix} is_match_whitelisted=true matchwhite_list_entry='${matchwhite_list_entry}' ${clean_output}"
|
|
continue
|
|
fi
|
|
fi
|
|
|
|
# shellcheck disable=SC2086
|
|
if dpkg-statoverride ${dpkg_admindir_parameter_existing_mode} --list "${file_name}" >/dev/null; then
|
|
log info "Existing mode already saved previously. Not saving again."
|
|
else
|
|
## Save existing_mode in separate database.
|
|
## Not using --update as not intending to enforce existing_mode.
|
|
# shellcheck disable=SC2086
|
|
echo_wrapper_audit silent dpkg-statoverride ${dpkg_admindir_parameter_existing_mode} --add "${existing_owner}" "${existing_group}" "${existing_mode}" "${file_name}"
|
|
fi
|
|
|
|
## No need to check "dpkg-statoverride --list" for existing entries.
|
|
## If existing_mode was correct already, we would not have reached this
|
|
## point. Since existing_mode is incorrect, remove from dpkg-statoverride
|
|
## and re-add.
|
|
|
|
## Remove from real database.
|
|
echo_wrapper_ignore silent dpkg-statoverride --remove "${file_name}"
|
|
|
|
## Remove from separate database.
|
|
# shellcheck disable=SC2086
|
|
echo_wrapper_ignore silent dpkg-statoverride ${dpkg_admindir_parameter_new_mode} --remove "${file_name}"
|
|
|
|
## Add to real database and use --update to make changes on disk.
|
|
echo_wrapper_audit verbose dpkg-statoverride --add --update "${existing_owner}" "${existing_group}" "${new_mode}" "${file_name}"
|
|
|
|
## Not using --update as this is only for recording.
|
|
# shellcheck disable=SC2086
|
|
echo_wrapper_audit silent dpkg-statoverride ${dpkg_admindir_parameter_new_mode} --add "${existing_owner}" "${existing_group}" "${new_mode}" "${file_name}"
|
|
|
|
## /usr/lib will hit ARG_MAX if using bash 'shopt -s globstar' and '/usr/lib/**'.
|
|
## Using 'find' with '-perm /u=s,g=s' is faster and avoids ARG_MAX.
|
|
## https://forums.whonix.org/t/disable-suid-binaries/7706/17
|
|
done < <(find "${fso_to_process}" -perm /u=s,g=s -print0)
|
|
|
|
## Sanity test.
|
|
if test ! "${should_be_counter}" = "${counter_actual}"; then
|
|
log info "File (parsed/wanted): '${fso_to_process}': (${counter_actual}/${should_be_counter})"
|
|
log error "Expected number of files to be parsed was not met." >&2
|
|
exit_code=202
|
|
fi
|
|
}
|
|
|
|
set_file_perms() {
|
|
log info "START parsing config file: '${config_file}'"
|
|
local line
|
|
while read -r line || test -n "${line}"; do
|
|
if test -z "${line}"; then
|
|
continue
|
|
fi
|
|
|
|
if [[ "${line}" =~ ^\s*# ]]; then
|
|
continue
|
|
fi
|
|
|
|
if ! [[ "${line}" =~ [0-9a-zA-Z/] ]]; then
|
|
exit_code=200
|
|
log error "Line contains invalid characters: '${line}'" >&2
|
|
## Safer to exit with error in this case.
|
|
## https://forums.whonix.org/t/disable-suid-binaries/7706/59
|
|
exit "${exit_code}"
|
|
fi
|
|
|
|
if test "${line}" = 'whitelists_disable_all=true'; then
|
|
whitelists_disable_all=true
|
|
log info "whitelists_disable_all=true"
|
|
continue
|
|
fi
|
|
|
|
#global fso
|
|
local mode_from_config owner_from_config group_from_config capability_from_config
|
|
if ! read -r fso mode_from_config owner_from_config group_from_config capability_from_config <<<"${line}"; then
|
|
exit_code=201
|
|
log error "Cannot parse line: '${line}'" >&2
|
|
## Debugging.
|
|
du -hs /tmp || true
|
|
echo "test -w /tmp: '$(test -w /tmp)'" >&2 || true
|
|
## Safer to exit with error in this case.
|
|
## https://forums.whonix.org/t/disable-suid-binaries/7706/59
|
|
exit "${exit_code}"
|
|
fi
|
|
|
|
log info "Parsing line: fso='${fso}' mode_from_config='${mode_from_config}' owner_from_config='${owner_from_config}' group_from_config='${group_from_config}' capability_from_config='${capability_from_config}'"
|
|
|
|
## Debugging.
|
|
#echo "line: '${line}'"
|
|
#echo "fso: '${fso}'"
|
|
#echo "mode_from_config: '${mode_from_config}'"
|
|
#echo "owner_from_config: '${owner_from_config}'"
|
|
|
|
local fso_without_trailing_slash
|
|
fso_without_trailing_slash="${fso%/}"
|
|
|
|
## TODO: test/add white spaces inside file name support
|
|
declare -g disable_white_list exact_white_list match_white_list
|
|
case "${mode_from_config}" in
|
|
disablewhitelist)
|
|
disable_white_list+=("${fso}")
|
|
continue
|
|
;;
|
|
exactwhitelist)
|
|
exact_white_list+=("${fso}")
|
|
continue
|
|
;;
|
|
matchwhitelist)
|
|
match_white_list+=("${fso}")
|
|
continue
|
|
;;
|
|
esac
|
|
|
|
if test ! -e "${fso}"; then
|
|
log info "File does not exist: '${fso}'"
|
|
continue
|
|
fi
|
|
|
|
## Use dpkg-statoverride so permissions are not reset during upgrades.
|
|
|
|
if test "${mode_from_config}" = "nosuid"; then
|
|
## If mode_from_config is "nosuid" the config does not set owner and
|
|
## group. Therefore do not enforce owner/group check.
|
|
add_nosuid_statoverride_entry
|
|
else
|
|
local string_length_of_mode_from_config
|
|
string_length_of_mode_from_config="${#mode_from_config}"
|
|
if test "${string_length_of_mode_from_config}" -gt "4"; then
|
|
log error "Invalid mode: '${mode_from_config}'" >&2
|
|
continue
|
|
fi
|
|
if test "${string_length_of_mode_from_config}" -lt "3"; then
|
|
log error "Invalid mode: '${mode_from_config}'" >&2
|
|
continue
|
|
fi
|
|
|
|
if ! grep --quiet --fixed-strings "${owner_from_config}:" "${store_dir}/private/passwd"; then
|
|
log error "Owner from config does not exist: '${owner_from_config}'" >&2
|
|
continue
|
|
fi
|
|
|
|
if ! grep --quiet --fixed-strings "${group_from_config}:" "${store_dir}/private/group"; then
|
|
log error "Group from config does not exist: '${group_from_config}'" >&2
|
|
continue
|
|
fi
|
|
|
|
local mode_for_grep
|
|
mode_for_grep="${mode_from_config}"
|
|
first_character_of_mode_from_config="${mode_from_config::1}"
|
|
if test "${first_character_of_mode_from_config}" = "0"; then
|
|
## Remove leading '0'.
|
|
mode_for_grep="${mode_from_config:1}"
|
|
fi
|
|
|
|
local stat_output
|
|
stat_output=""
|
|
if ! stat_output="$(stat -c '%n\0%a\0%U\0%G\0%' "${fso_without_trailing_slash}")"; then
|
|
log error "Failed to run 'stat' on file: '${fso_without_trailing_slash}'!" >&2
|
|
continue
|
|
fi
|
|
|
|
local arr file_name file_name_from_stat existing_mode existing_owner existing_group
|
|
readarray -d '\0' -t arr <<< "${stat_output}"
|
|
file_name="${fso_without_trailing_slash}"
|
|
|
|
if test "${#arr[@]}" = 0; then
|
|
log error "Line is empty. Stat output: '${stat_output}', line: '${line}'" >&2
|
|
continue
|
|
fi
|
|
|
|
file_name_from_stat="${arr[0]}"
|
|
existing_mode="${arr[1]}"
|
|
existing_owner="${arr[2]}"
|
|
existing_group="${arr[3]}"
|
|
|
|
if test -z "${file_name}"; then
|
|
log error "File name is empty. Stat output: '${stat_output}', line: '${line}'" >&2
|
|
continue
|
|
fi
|
|
if test -z "${existing_mode}"; then
|
|
log error "Existing mode is empty. Stat output: '${stat_output}', line: '${line}'" >&2
|
|
continue
|
|
fi
|
|
if test -z "${existing_owner}"; then
|
|
log error "Existing_owner is empty. Stat output: '${stat_output}' | line: '${line}'" >&2
|
|
continue
|
|
fi
|
|
if test -z "${existing_group}"; then
|
|
log error "Existing group is empty. Stat output: '${stat_output}', line: '${line}'" >&2
|
|
continue
|
|
fi
|
|
|
|
## Check there is an entry for the fso.
|
|
##
|
|
## example: dpkg-statoverride --list | grep /home
|
|
## output:
|
|
## root root 755 /home
|
|
##
|
|
## dpkg-statoverride does not show leading '0'.
|
|
local dpkg_statoverride_list_output=""
|
|
local dpkg_statoverride_list_exit_code=0
|
|
dpkg_statoverride_list_output="$(dpkg-statoverride --list "${fso_without_trailing_slash}")" || {
|
|
dpkg_statoverride_list_exit_code=$?
|
|
true
|
|
}
|
|
|
|
if test "${dpkg_statoverride_list_exit_code}" = "0"; then
|
|
local grep_line
|
|
grep_line="${owner_from_config} ${group_from_config} ${mode_for_grep} ${fso_without_trailing_slash}"
|
|
if echo "${dpkg_statoverride_list_output}" | grep --quiet --fixed-strings "${grep_line}"; then
|
|
log info "The owner/group/mode matches fso entry. No further action required."
|
|
else
|
|
log info "The owner/group/mode does not match fso entry, updating entry."
|
|
## fso_without_trailing_slash instead of fso to prevent
|
|
## "dpkg-statoverride: warning: stripping trailing /"
|
|
|
|
# shellcheck disable=SC2086
|
|
if dpkg-statoverride ${dpkg_admindir_parameter_existing_mode} --list "${fso_without_trailing_slash}" >/dev/null; then
|
|
log info "Existing mode already saved previously. Not saving again."
|
|
else
|
|
## Save existing_mode in separate database.
|
|
## Not using --update as not intending to enforce existing_mode.
|
|
# shellcheck disable=SC2086
|
|
echo_wrapper_audit silent dpkg-statoverride ${dpkg_admindir_parameter_existing_mode} --add "${existing_owner}" "${existing_group}" "${existing_mode}" "${fso_without_trailing_slash}"
|
|
fi
|
|
|
|
# shellcheck disable=SC2086
|
|
echo_wrapper_ignore silent dpkg-statoverride ${dpkg_admindir_parameter_new_mode} --remove "${fso_without_trailing_slash}"
|
|
|
|
## Remove from and add to real database.
|
|
echo_wrapper_ignore silent dpkg-statoverride --remove "${fso_without_trailing_slash}"
|
|
echo_wrapper_audit verbose dpkg-statoverride --add --update "${owner_from_config}" "${group_from_config}" "${mode_from_config}" "${fso_without_trailing_slash}"
|
|
|
|
## Save in separate database.
|
|
## Not using --update as this is only for saving.
|
|
# shellcheck disable=SC2086
|
|
echo_wrapper_audit silent dpkg-statoverride ${dpkg_admindir_parameter_new_mode} --add "${owner_from_config}" "${group_from_config}" "${mode_from_config}" "${fso_without_trailing_slash}"
|
|
fi
|
|
else
|
|
log info "There is no fso entry, adding one."
|
|
|
|
# shellcheck disable=SC2086
|
|
if dpkg-statoverride ${dpkg_admindir_parameter_existing_mode} --list "${fso_without_trailing_slash}" >/dev/null; then
|
|
log info "Existing mode already saved previously. Not saving again."
|
|
else
|
|
## Save existing_mode in separate database.
|
|
## Not using --update as not intending to enforce existing_mode.
|
|
# shellcheck disable=SC2086
|
|
echo_wrapper_audit silent dpkg-statoverride ${dpkg_admindir_parameter_existing_mode} --add "${existing_owner}" "${existing_group}" "${existing_mode}" "${fso_without_trailing_slash}"
|
|
fi
|
|
|
|
## Add to real database.
|
|
echo_wrapper_audit verbose dpkg-statoverride --add --update "${owner_from_config}" "${group_from_config}" "${mode_from_config}" "${fso_without_trailing_slash}"
|
|
|
|
## Save in separate database.
|
|
## Not using --update as this is only for saving.
|
|
# shellcheck disable=SC2086
|
|
echo_wrapper_audit silent dpkg-statoverride ${dpkg_admindir_parameter_new_mode} --add "${owner_from_config}" "${group_from_config}" "${mode_from_config}" "${fso_without_trailing_slash}"
|
|
fi
|
|
fi
|
|
if test -z "${capability_from_config}"; then
|
|
continue
|
|
fi
|
|
|
|
if test "${capability_from_config}" = "none"; then
|
|
## https://forums.whonix.org/t/disable-suid-binaries/7706/45
|
|
## sudo setcap -r /bin/ping 2>/dev/null
|
|
## Failed to set capabilities on file '/bin/ping' (No data available)
|
|
## The value of the capability argument is not permitted for a file. Or
|
|
## the file is not a regular (non-symlink) file
|
|
## Therefore use echo_wrapper_ignore.
|
|
echo_wrapper_ignore verbose setcap -r "${fso}"
|
|
getcap_output="$(getcap "${fso}")"
|
|
if test -n "${getcap_output}"; then
|
|
exit_code=205
|
|
log error "Removing capabilities failed. File: '${fso}'" >&2
|
|
continue
|
|
fi
|
|
else
|
|
if ! capsh --print | grep --fixed-strings "Bounding set" | grep --quiet "${capability_from_config}"; then
|
|
log error "Capability from config does not exist: '${capability_from_config}'" >&2
|
|
continue
|
|
fi
|
|
|
|
## feature request: dpkg-statoverride: support for capabilities
|
|
## https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=502580
|
|
echo_wrapper_audit verbose setcap "${capability_from_config}+ep" "${fso}"
|
|
fi
|
|
|
|
done <"${config_file}"
|
|
log info "END parsing config file: '${config_file}'"
|
|
}
|
|
|
|
parse_config_folder() {
|
|
touch "${store_dir}/private/passwd"
|
|
chmod og-rwx "${store_dir}/private/passwd"
|
|
touch "${store_dir}/private/group"
|
|
chmod og-rwx "${store_dir}/private/group"
|
|
|
|
local passwd_file_contents_temp
|
|
## Query contents of password and group databases only once and buffer them
|
|
##
|
|
## If we don't buffer we sometimes get incorrect results when checking for
|
|
## entries using 'if getent passwd | grep --quiet '^root:'; ...' since
|
|
## 'grep' exits after the first match in this case causing 'getent' to
|
|
## receive SIGPIPE, which then fails the pipeline since 'set -o pipefail' is
|
|
## set for this script.
|
|
passwd_file_contents_temp=$(getent passwd)
|
|
echo "${passwd_file_contents_temp}" | tee "${store_dir}/private/passwd" >/dev/null
|
|
group_file_contents_temp=$(getent group)
|
|
echo "${group_file_contents_temp}" | tee "${store_dir}/private/group" >/dev/null
|
|
|
|
#passwd_file_contents="$(cat "${store_dir}/private/passwd")"
|
|
#group_file_contents="$(cat "${store_dir}/private/group")"
|
|
|
|
shopt -s nullglob
|
|
for config_file in \
|
|
/etc/permission-hardener.d/*.conf \
|
|
/usr/local/etc/permission-hardener.d/*.conf \
|
|
/etc/permission-hardening.d/*.conf \
|
|
/usr/local/etc/permission-hardening.d/*.conf
|
|
do
|
|
set_file_perms
|
|
|
|
done
|
|
}
|
|
|
|
apply() {
|
|
check_root
|
|
make_store_dir
|
|
sanity_tests
|
|
parse_config_folder
|
|
|
|
log notice "\
|
|
To compare the current and previous permission modes, install 'meld' (or preferred diff tool) for comparison of file mode changes:
|
|
sudo apt install --no-install-recommends meld
|
|
meld ${store_dir}/existing_mode/statoverride ${store_dir}/new_mode/statoverride"
|
|
}
|
|
|
|
spare() {
|
|
check_root
|
|
make_store_dir
|
|
|
|
remove_file="${1}"
|
|
exit_code=0
|
|
dpkg_admindir_parameter_existing_mode="--admindir ${store_dir}/existing_mode"
|
|
dpkg_admindir_parameter_new_mode="--admindir ${store_dir}/new_mode"
|
|
|
|
if test ! -f "${store_dir}/existing_mode/statoverride"; then
|
|
true "DEBUG: Stat file does not exist, hardening was not applied before."
|
|
return 0
|
|
fi
|
|
|
|
local line
|
|
while read -r line; do
|
|
## example line:
|
|
## root root 4755 /usr/lib/eject/dmcrypt-get-device
|
|
|
|
local owner group mode file_name
|
|
if ! read -r owner group mode file_name <<< "${line}"; then
|
|
exit_code=201
|
|
log error "Cannot parse line: '${line}'" >&2
|
|
continue
|
|
fi
|
|
log info "Parsing line: owner='${owner}' group='${group}' mode='${mode}' file_name='${file_name}'"
|
|
|
|
if test "${remove_file}" = "all"; then
|
|
verbose=""
|
|
remove_one=false
|
|
else
|
|
if test "${remove_file}" = "${file_name}"; then
|
|
verbose="--verbose"
|
|
remove_one=true
|
|
echo "${remove_one}" | tee "${store_dir}/remove_one" >/dev/null
|
|
else
|
|
echo "false" | tee "${store_dir}/remove_one" >/dev/null
|
|
continue
|
|
fi
|
|
fi
|
|
|
|
if test "${remove_one}" = "true"; then
|
|
set -o xtrace
|
|
fi
|
|
|
|
if test -e "${file_name}"; then
|
|
# shellcheck disable=SC2086
|
|
chown ${verbose} "${owner}:${group}" "${file_name}" || exit_code=202
|
|
## chmod need to be run after chown since chown removes suid.
|
|
## https://unix.stackexchange.com/questions/53665/chown-removes-setuid-bit-bug-or-feature
|
|
# shellcheck disable=SC2086
|
|
chmod ${verbose} "${mode}" "${file_name}" || exit_code=203
|
|
else
|
|
log info "File does not exist: '${file_name}'"
|
|
fi
|
|
|
|
dpkg-statoverride --remove "${file_name}" &>/dev/null || true
|
|
# shellcheck disable=SC2086
|
|
dpkg-statoverride ${dpkg_admindir_parameter_existing_mode} --remove "${file_name}" &>/dev/null || true
|
|
# shellcheck disable=SC2086
|
|
dpkg-statoverride ${dpkg_admindir_parameter_new_mode} --remove "${file_name}" &>/dev/null || true
|
|
|
|
if test "${remove_one}" = "true"; then
|
|
set +o xtrace
|
|
break
|
|
fi
|
|
|
|
done < "${store_dir}/existing_mode/statoverride"
|
|
|
|
if test ! "${remove_file}" = "all"; then
|
|
if test "$(cat "${store_dir}/remove_one")" = "false"; then
|
|
log info "No file was removed.
|
|
|
|
File '${remove_file}' has not been removed from SUID Disabler and Permission Hardener during this invocation. This is expected if already done earlier.
|
|
|
|
This program expects the full path to the file. Example:
|
|
$0 disable /usr/bin/newgrp # absolute path: works
|
|
$0 disable newgrp # relative path: does not work
|
|
|
|
To remove all:
|
|
$0 disable all
|
|
|
|
This change might not be permanent. For full instructions, see:
|
|
https://www.kicksecure.com/wiki/SUID_Disabler_and_Permission_Hardener
|
|
|
|
To view list of changed by SUID Disabler and Permission Hardener:
|
|
https://www.kicksecure.com/wiki/SUID_Disabler_and_Permission_Hardener#View_List_of_Permissions_Changed_by_SUID_Disabler_and_Permission_Hardener
|
|
|
|
For re-enabling any specific SUID binary:
|
|
https://www.kicksecure.com/wiki/SUID_Disabler_and_Permission_Hardener#Re-Enable_Specific_SUID_Binaries
|
|
|
|
For completely disabling SUID Disabler and Permission Hardener:
|
|
https://www.kicksecure.com/wiki/SUID_Disabler_and_Permission_Hardener#Disable_SUID_Disabler_and_Permission_Hardener"
|
|
fi
|
|
fi
|
|
}
|
|
|
|
check_root(){
|
|
if test "$(id -u)" != "0"; then
|
|
log error "Not running as root, aborting."
|
|
exit 1
|
|
fi
|
|
}
|
|
|
|
usage(){
|
|
echo "Usage: ${0##*/} enable
|
|
${0##*/} disable [FILE|all]
|
|
|
|
Examples:
|
|
${0##*/} enable
|
|
${0##*/} disable all
|
|
${0##*/} disable /usr/bin/newgrp" >&2
|
|
exit "${1}"
|
|
}
|
|
|
|
case "${1:-}" in
|
|
enable) shift; apply "$@";;
|
|
disable)
|
|
shift
|
|
case "${1:-}" in
|
|
"") usage 1;;
|
|
*) spare "${1}";;
|
|
esac
|
|
;;
|
|
-h|--help) usage 0;;
|
|
*) usage 1;;
|
|
esac
|
|
|
|
if test "${exit_code}" != "0"; then
|
|
log error "Exiting with non-zero exit code: '${exit_code}'" >&2
|
|
fi
|
|
|
|
exit "${exit_code}"
|