diff options
Diffstat (limited to 'tools/testing/selftests/kexec/test_kexec_file_load.sh')
| -rwxr-xr-x | tools/testing/selftests/kexec/test_kexec_file_load.sh | 243 |
1 files changed, 243 insertions, 0 deletions
diff --git a/tools/testing/selftests/kexec/test_kexec_file_load.sh b/tools/testing/selftests/kexec/test_kexec_file_load.sh new file mode 100755 index 000000000..c9ccb3c93 --- /dev/null +++ b/tools/testing/selftests/kexec/test_kexec_file_load.sh @@ -0,0 +1,243 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0 +# +# Loading a kernel image via the kexec_file_load syscall can verify either +# the IMA signature stored in the security.ima xattr or the PE signature, +# both signatures depending on the IMA policy, or none. +# +# To determine whether the kernel image is signed, this test depends +# on pesign and getfattr. This test also requires the kernel to be +# built with CONFIG_IKCONFIG enabled and either CONFIG_IKCONFIG_PROC +# enabled or access to the extract-ikconfig script. + +TEST="KEXEC_FILE_LOAD" +. ./kexec_common_lib.sh + +trap "{ rm -f $IKCONFIG ; }" EXIT + +# Some of the IMA builtin policies may require the kexec kernel image to +# be signed, but these policy rules may be replaced with a custom +# policy. Only CONFIG_IMA_APPRAISE_REQUIRE_KEXEC_SIGS persists after +# loading a custom policy. Check if it is enabled, before reading the +# IMA runtime sysfs policy file. +# Return 1 for IMA signature required and 0 for not required. +is_ima_sig_required() +{ + local ret=0 + + kconfig_enabled "CONFIG_IMA_APPRAISE_REQUIRE_KEXEC_SIGS=y" \ + "IMA kernel image signature required" + if [ $? -eq 1 ]; then + log_info "IMA signature required" + return 1 + fi + + # The architecture specific or a custom policy may require the + # kexec kernel image be signed. Policy rules are walked + # sequentially. As a result, a policy rule may be defined, but + # might not necessarily be used. This test assumes if a policy + # rule is specified, that is the intent. + + # First check for appended signature (modsig), then xattr + if [ $ima_read_policy -eq 1 ]; then + check_ima_policy "appraise" "func=KEXEC_KERNEL_CHECK" \ + "appraise_type=imasig|modsig" + ret=$? + if [ $ret -eq 1 ]; then + log_info "IMA or appended(modsig) signature required" + else + check_ima_policy "appraise" "func=KEXEC_KERNEL_CHECK" \ + "appraise_type=imasig" + ret=$? + [ $ret -eq 1 ] && log_info "IMA signature required"; + fi + fi + return $ret +} + +# The kexec_file_load_test() is complicated enough, require pesign. +# Return 1 for PE signature found and 0 for not found. +check_for_pesig() +{ + which pesign > /dev/null 2>&1 || log_skip "pesign not found" + + pesign -i $KERNEL_IMAGE --show-signature | grep -q "No signatures" + local ret=$? + if [ $ret -eq 1 ]; then + log_info "kexec kernel image PE signed" + else + log_info "kexec kernel image not PE signed" + fi + return $ret +} + +# The kexec_file_load_test() is complicated enough, require getfattr. +# Return 1 for IMA signature found and 0 for not found. +check_for_imasig() +{ + local ret=0 + + which getfattr > /dev/null 2>&1 + if [ $? -eq 1 ]; then + log_skip "getfattr not found" + fi + + line=$(getfattr -n security.ima -e hex --absolute-names $KERNEL_IMAGE 2>&1) + echo $line | grep -q "security.ima=0x03" + if [ $? -eq 0 ]; then + ret=1 + log_info "kexec kernel image IMA signed" + else + log_info "kexec kernel image not IMA signed" + fi + return $ret +} + +# Return 1 for appended signature (modsig) found and 0 for not found. +check_for_modsig() +{ + local module_sig_string="~Module signature appended~" + local ret=0 + + tail --bytes $((${#module_sig_string} + 1)) $KERNEL_IMAGE | \ + grep -q "$module_sig_string" + if [ $? -eq 0 ]; then + ret=1 + log_info "kexec kernel image modsig signed" + else + log_info "kexec kernel image not modsig signed" + fi + return $ret +} + +kexec_file_load_test() +{ + local succeed_msg="kexec_file_load succeeded" + local failed_msg="kexec_file_load failed" + local key_msg="try enabling the CONFIG_INTEGRITY_PLATFORM_KEYRING" + + line=$(kexec --load --kexec-file-syscall $KERNEL_IMAGE 2>&1) + + if [ $? -eq 0 ]; then + kexec --unload --kexec-file-syscall + + # In secureboot mode with an architecture specific + # policy, make sure either an IMA or PE signature exists. + if [ $secureboot -eq 1 ] && [ $arch_policy -eq 1 ] && \ + [ $ima_signed -eq 0 ] && [ $pe_signed -eq 0 ] \ + && [ $ima_modsig -eq 0 ]; then + log_fail "$succeed_msg (missing sig)" + fi + + if [ $kexec_sig_required -eq 1 -o $pe_sig_required -eq 1 ] \ + && [ $pe_signed -eq 0 ]; then + log_fail "$succeed_msg (missing PE sig)" + fi + + if [ $ima_sig_required -eq 1 ] && [ $ima_signed -eq 0 ] \ + && [ $ima_modsig -eq 0 ]; then + log_fail "$succeed_msg (missing IMA sig)" + fi + + if [ $pe_sig_required -eq 0 ] && [ $ima_appraise -eq 1 ] \ + && [ $ima_sig_required -eq 0 ] && [ $ima_signed -eq 0 ] \ + && [ $ima_read_policy -eq 0 ]; then + log_fail "$succeed_msg (possibly missing IMA sig)" + fi + + if [ $pe_sig_required -eq 0 ] && [ $ima_appraise -eq 0 ]; then + log_info "No signature verification required" + elif [ $pe_sig_required -eq 0 ] && [ $ima_appraise -eq 1 ] \ + && [ $ima_sig_required -eq 0 ] && [ $ima_signed -eq 0 ] \ + && [ $ima_read_policy -eq 1 ]; then + log_info "No signature verification required" + fi + + log_pass "$succeed_msg" + fi + + # Check the reason for the kexec_file_load failure + echo $line | grep -q "Required key not available" + if [ $? -eq 0 ]; then + if [ $platform_keyring -eq 0 ]; then + log_pass "$failed_msg (-ENOKEY), $key_msg" + else + log_pass "$failed_msg (-ENOKEY)" + fi + fi + + if [ $kexec_sig_required -eq 1 -o $pe_sig_required -eq 1 ] \ + && [ $pe_signed -eq 0 ]; then + log_pass "$failed_msg (missing PE sig)" + fi + + if [ $ima_sig_required -eq 1 ] && [ $ima_signed -eq 0 ]; then + log_pass "$failed_msg (missing IMA sig)" + fi + + if [ $pe_sig_required -eq 0 ] && [ $ima_appraise -eq 1 ] \ + && [ $ima_sig_required -eq 0 ] && [ $ima_read_policy -eq 0 ] \ + && [ $ima_signed -eq 0 ]; then + log_pass "$failed_msg (possibly missing IMA sig)" + fi + + log_pass "$failed_msg" + return 0 +} + +# kexec requires root privileges +require_root_privileges + +# get the kernel config +get_kconfig + +kconfig_enabled "CONFIG_KEXEC_FILE=y" "kexec_file_load is enabled" +if [ $? -eq 0 ]; then + log_skip "kexec_file_load is not enabled" +fi + +# Determine which kernel config options are enabled +kconfig_enabled "CONFIG_IMA_APPRAISE=y" "IMA enabled" +ima_appraise=$? + +kconfig_enabled "CONFIG_IMA_ARCH_POLICY=y" \ + "architecture specific policy enabled" +arch_policy=$? + +kconfig_enabled "CONFIG_INTEGRITY_PLATFORM_KEYRING=y" \ + "platform keyring enabled" +platform_keyring=$? + +kconfig_enabled "CONFIG_IMA_READ_POLICY=y" "reading IMA policy permitted" +ima_read_policy=$? + +kconfig_enabled "CONFIG_KEXEC_SIG_FORCE=y" \ + "kexec signed kernel image required" +kexec_sig_required=$? + +kconfig_enabled "CONFIG_KEXEC_BZIMAGE_VERIFY_SIG=y" \ + "PE signed kernel image required" +pe_sig_required=$? + +is_ima_sig_required +ima_sig_required=$? + +get_secureboot_mode +secureboot=$? + +# Are there pe and ima signatures +if [ "$(get_arch)" == 'ppc64le' ]; then + pe_signed=0 +else + check_for_pesig + pe_signed=$? +fi + +check_for_imasig +ima_signed=$? + +check_for_modsig +ima_modsig=$? + +# Test loading the kernel image via kexec_file_load syscall +kexec_file_load_test |