In addition to the PE/COFF and IMA xattr signatures, the kexec kernel image can be signed with an appended signature, using the same scripts/sign-file tool that is used to sign kernel modules.

This patch adds support for detecting a kernel image signed with an appended signature and updates the existing test messages appropriately.

Reviewed-by: Petr Vorel pvorel@suse.cz Signed-off-by: Mimi Zohar zohar@linux.ibm.com --- .../selftests/kexec/test_kexec_file_load.sh | 38 +++++++++++++++++++--- 1 file changed, 34 insertions(+), 4 deletions(-)

diff --git a/tools/testing/selftests/kexec/test_kexec_file_load.sh b/tools/testing/selftests/kexec/test_kexec_file_load.sh index fa7c24e8eefb..2ff600388c30 100755 --- a/tools/testing/selftests/kexec/test_kexec_file_load.sh +++ b/tools/testing/selftests/kexec/test_kexec_file_load.sh @@ -37,11 +37,20 @@ is_ima_sig_required() # 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 [ $ima_read_policy -eq 1 ]; then check_ima_policy "appraise" "func=KEXEC_KERNEL_CHECK" \ - "appraise_type=imasig" + "appraise_type=imasig|modsig" ret=$? - [ $ret -eq 1 ] && log_info "IMA signature required"; + 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 } @@ -84,6 +93,22 @@ check_for_imasig() 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 sig="$(tail --bytes $((${#module_sig_string} + 1)) $KERNEL_IMAGE)" + local ret=0 + + if [ "$sig" == "$module_sig_string" ]; 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" @@ -98,7 +123,8 @@ kexec_file_load_test() # 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 ]; then + [ $ima_signed -eq 0 ] && [ $pe_signed -eq 0 ] \ + && [ $ima_modsig -eq 0 ]; then log_fail "$succeed_msg (missing sig)" fi

@@ -107,7 +133,8 @@ kexec_file_load_test() log_fail "$succeed_msg (missing PE sig)" fi

- if [ $ima_sig_required -eq 1 ] && [ $ima_signed -eq 0 ]; then + if [ $ima_sig_required -eq 1 ] && [ $ima_signed -eq 0 ] \ + && [ $ima_modsig -eq 0 ]; then log_fail "$succeed_msg (missing IMA sig)" fi

@@ -204,5 +231,8 @@ pe_signed=$? check_for_imasig ima_signed=$?

+check_for_modsig +ima_modsig=$? + # Test loading the kernel image via kexec_file_load syscall kexec_file_load_test