| #!/usr/bin/env bash |
| # SPDX-License-Identifier: GPL-2.0 |
| # |
| # Test the "inc" interpreter. |
| # |
| # See include/uapi/linux/securebits.h, include/uapi/linux/fcntl.h and |
| # samples/check-exec/inc.c |
| # |
| # Copyright © 2024 Microsoft Corporation |
| |
| set -u -e -o pipefail |
| |
| EXPECTED_OUTPUT="1" |
| exec 2>/dev/null |
| |
| DIR="$(dirname $(readlink -f "$0"))" |
| source "${DIR}"/../kselftest/ktap_helpers.sh |
| |
| exec_direct() { |
| local expect="$1" |
| local script="$2" |
| shift 2 |
| local ret=0 |
| local out |
| |
| # Updates PATH for `env` to execute the `inc` interpreter. |
| out="$(PATH="." "$@" "${script}")" || ret=$? |
| |
| if [[ ${ret} -ne ${expect} ]]; then |
| echo "ERROR: Wrong expectation for direct file execution: ${ret}" |
| return 1 |
| fi |
| if [[ ${ret} -eq 0 && "${out}" != "${EXPECTED_OUTPUT}" ]]; then |
| echo "ERROR: Wrong output for direct file execution: ${out}" |
| return 1 |
| fi |
| } |
| |
| exec_indirect() { |
| local expect="$1" |
| local script="$2" |
| shift 2 |
| local ret=0 |
| local out |
| |
| # Script passed as argument. |
| out="$("$@" ./inc "${script}")" || ret=$? |
| |
| if [[ ${ret} -ne ${expect} ]]; then |
| echo "ERROR: Wrong expectation for indirect file execution: ${ret}" |
| return 1 |
| fi |
| if [[ ${ret} -eq 0 && "${out}" != "${EXPECTED_OUTPUT}" ]]; then |
| echo "ERROR: Wrong output for indirect file execution: ${out}" |
| return 1 |
| fi |
| } |
| |
| exec_stdin_reg() { |
| local expect="$1" |
| local script="$2" |
| shift 2 |
| local ret=0 |
| local out |
| |
| # Executing stdin must be allowed if the related file is executable. |
| out="$("$@" ./inc -i < "${script}")" || ret=$? |
| |
| if [[ ${ret} -ne ${expect} ]]; then |
| echo "ERROR: Wrong expectation for stdin regular file execution: ${ret}" |
| return 1 |
| fi |
| if [[ ${ret} -eq 0 && "${out}" != "${EXPECTED_OUTPUT}" ]]; then |
| echo "ERROR: Wrong output for stdin regular file execution: ${out}" |
| return 1 |
| fi |
| } |
| |
| exec_stdin_pipe() { |
| local expect="$1" |
| shift |
| local ret=0 |
| local out |
| |
| # A pipe is not executable. |
| out="$(cat script-exec.inc | "$@" ./inc -i)" || ret=$? |
| |
| if [[ ${ret} -ne ${expect} ]]; then |
| echo "ERROR: Wrong expectation for stdin pipe execution: ${ret}" |
| return 1 |
| fi |
| } |
| |
| exec_argument() { |
| local expect="$1" |
| local ret=0 |
| shift |
| local out |
| |
| # Script not coming from a file must not be executed. |
| out="$("$@" ./inc -c "$(< script-exec.inc)")" || ret=$? |
| |
| if [[ ${ret} -ne ${expect} ]]; then |
| echo "ERROR: Wrong expectation for arbitrary argument execution: ${ret}" |
| return 1 |
| fi |
| if [[ ${ret} -eq 0 && "${out}" != "${EXPECTED_OUTPUT}" ]]; then |
| echo "ERROR: Wrong output for arbitrary argument execution: ${out}" |
| return 1 |
| fi |
| } |
| |
| exec_interactive() { |
| exec_stdin_pipe "$@" |
| exec_argument "$@" |
| } |
| |
| ktap_test() { |
| ktap_test_result "$*" "$@" |
| } |
| |
| ktap_print_header |
| ktap_set_plan 28 |
| |
| # Without secbit configuration, nothing is changed. |
| |
| ktap_print_msg "By default, executable scripts are allowed to be interpreted and executed." |
| ktap_test exec_direct 0 script-exec.inc |
| ktap_test exec_indirect 0 script-exec.inc |
| |
| ktap_print_msg "By default, executable stdin is allowed to be interpreted." |
| ktap_test exec_stdin_reg 0 script-exec.inc |
| |
| ktap_print_msg "By default, non-executable scripts are allowed to be interpreted, but not directly executed." |
| # We get 126 because of direct execution by Bash. |
| ktap_test exec_direct 126 script-noexec.inc |
| ktap_test exec_indirect 0 script-noexec.inc |
| |
| ktap_print_msg "By default, non-executable stdin is allowed to be interpreted." |
| ktap_test exec_stdin_reg 0 script-noexec.inc |
| |
| ktap_print_msg "By default, interactive commands are allowed to be interpreted." |
| ktap_test exec_interactive 0 |
| |
| # With only file restriction: protect non-malicious users from inadvertent errors (e.g. python ~/Downloads/*.py). |
| |
| ktap_print_msg "With -f, executable scripts are allowed to be interpreted and executed." |
| ktap_test exec_direct 0 script-exec.inc ./set-exec -f -- |
| ktap_test exec_indirect 0 script-exec.inc ./set-exec -f -- |
| |
| ktap_print_msg "With -f, executable stdin is allowed to be interpreted." |
| ktap_test exec_stdin_reg 0 script-exec.inc ./set-exec -f -- |
| |
| ktap_print_msg "With -f, non-executable scripts are not allowed to be executed nor interpreted." |
| # Direct execution of non-executable script is alwayse denied by the kernel. |
| ktap_test exec_direct 1 script-noexec.inc ./set-exec -f -- |
| ktap_test exec_indirect 1 script-noexec.inc ./set-exec -f -- |
| |
| ktap_print_msg "With -f, non-executable stdin is allowed to be interpreted." |
| ktap_test exec_stdin_reg 0 script-noexec.inc ./set-exec -f -- |
| |
| ktap_print_msg "With -f, interactive commands are allowed to be interpreted." |
| ktap_test exec_interactive 0 ./set-exec -f -- |
| |
| # With only denied interactive commands: check or monitor script content (e.g. with LSM). |
| |
| ktap_print_msg "With -i, executable scripts are allowed to be interpreted and executed." |
| ktap_test exec_direct 0 script-exec.inc ./set-exec -i -- |
| ktap_test exec_indirect 0 script-exec.inc ./set-exec -i -- |
| |
| ktap_print_msg "With -i, executable stdin is allowed to be interpreted." |
| ktap_test exec_stdin_reg 0 script-exec.inc ./set-exec -i -- |
| |
| ktap_print_msg "With -i, non-executable scripts are allowed to be interpreted, but not directly executed." |
| # Direct execution of non-executable script is alwayse denied by the kernel. |
| ktap_test exec_direct 1 script-noexec.inc ./set-exec -i -- |
| ktap_test exec_indirect 0 script-noexec.inc ./set-exec -i -- |
| |
| ktap_print_msg "With -i, non-executable stdin is not allowed to be interpreted." |
| ktap_test exec_stdin_reg 1 script-noexec.inc ./set-exec -i -- |
| |
| ktap_print_msg "With -i, interactive commands are not allowed to be interpreted." |
| ktap_test exec_interactive 1 ./set-exec -i -- |
| |
| # With both file restriction and denied interactive commands: only allow executable scripts. |
| |
| ktap_print_msg "With -fi, executable scripts are allowed to be interpreted and executed." |
| ktap_test exec_direct 0 script-exec.inc ./set-exec -fi -- |
| ktap_test exec_indirect 0 script-exec.inc ./set-exec -fi -- |
| |
| ktap_print_msg "With -fi, executable stdin is allowed to be interpreted." |
| ktap_test exec_stdin_reg 0 script-exec.inc ./set-exec -fi -- |
| |
| ktap_print_msg "With -fi, non-executable scripts are not allowed to be interpreted nor executed." |
| # Direct execution of non-executable script is alwayse denied by the kernel. |
| ktap_test exec_direct 1 script-noexec.inc ./set-exec -fi -- |
| ktap_test exec_indirect 1 script-noexec.inc ./set-exec -fi -- |
| |
| ktap_print_msg "With -fi, non-executable stdin is not allowed to be interpreted." |
| ktap_test exec_stdin_reg 1 script-noexec.inc ./set-exec -fi -- |
| |
| ktap_print_msg "With -fi, interactive commands are not allowed to be interpreted." |
| ktap_test exec_interactive 1 ./set-exec -fi -- |
| |
| ktap_finished |
