Re: [PATCH 2/3] scripts/ima: define a set of common functions

Dave Young
2019-02-28T13:41:57Z

Hi Mimi,

Sorry for jumping in late, just noticed this kexec selftests, I think we
also need a kexec load test not only for ima, but for general kexec

On 01/31/19 at 01:55pm, Mimi Zohar wrote:
> Define and move get_secureboot_mode() to a common file for use by other
> tests.
>
> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
> ---
> tools/testing/selftests/ima/common_lib.sh | 20 ++++++++++++++++++++
> tools/testing/selftests/ima/test_kexec_load.sh | 17 +++--------------
> 2 files changed, 23 insertions(+), 14 deletions(-)
> create mode 100755 tools/testing/selftests/ima/common_lib.sh
>
> diff --git a/tools/testing/selftests/ima/common_lib.sh b/tools/testing/selftests/ima/common_lib.sh
> new file mode 100755
> index 000000000000..ae097a634da5
> --- /dev/null
> +++ b/tools/testing/selftests/ima/common_lib.sh
> @@ -0,0 +1,20 @@
> +#!/bin/sh
> +# SPDX-License-Identifier: GPL-2.0+
> +
> +get_secureboot_mode()
> +{
> + EFIVARFS="/sys/firmware/efi/efivars"
> + # Make sure that efivars is mounted in the normal location
> + if ! grep -q "^\S\+ $EFIVARFS efivarfs" /proc/mounts; then
> + echo "$TEST: efivars is not mounted on $EFIVARFS" >&2
> + exit $ksft_skip
> + fi
> +
> + # Get secureboot mode
> + file="$EFIVARFS/SecureBoot-*"
> + if [ ! -e $file ]; then
> + echo "$TEST: unknown secureboot mode" >&2
> + exit $ksft_skip
> + fi
> + return `hexdump $file | awk '{print substr($4,length($4),1)}'`
> +}

Do you want to get the Secureboot status here?
I got some advice from Peter Jones previously, thus we have below
in our kdump scripts:
https://src.fedoraproject.org/cgit/rpms/kexec-tools.git/tree/kdump-lib.sh

See the function is_secure_boot_enforced(), probably you can refer to
that function and check setup mode as well.

> diff --git a/tools/testing/selftests/ima/test_kexec_load.sh b/tools/testing/selftests/ima/test_kexec_load.sh
> index 74423c4229e2..5e3566738888 100755
> --- a/tools/testing/selftests/ima/test_kexec_load.sh
> +++ b/tools/testing/selftests/ima/test_kexec_load.sh
> @@ -5,7 +5,7 @@
> # is booted in secureboot mode.
>
> TEST="$0"
> -EFIVARFS="/sys/firmware/efi/efivars"
> +. ./common_lib.sh
> rc=0
>
> # Kselftest framework requirement - SKIP code is 4.
> @@ -17,19 +17,8 @@ if [ $(id -ru) != 0 ]; then
> exit $ksft_skip
> fi
>
> -# Make sure that efivars is mounted in the normal location
> -if ! grep -q "^\S\+ $EFIVARFS efivarfs" /proc/mounts; then
> - echo "$TEST: efivars is not mounted on $EFIVARFS" >&2
> - exit $ksft_skip
> -fi
> -
> -# Get secureboot mode
> -file="$EFIVARFS/SecureBoot-*"
> -if [ ! -e $file ]; then
> - echo "$TEST: unknown secureboot mode" >&2
> - exit $ksft_skip
> -fi
> -secureboot=`hexdump $file | awk '{print substr($4,length($4),1)}'`
> +get_secureboot_mode
> +secureboot=$?
>
> # kexec_load should fail in secure boot mode
> KERNEL_IMAGE="/boot/vmlinuz-`uname -r`"
> --
> 2.7.5
>
Thanks
Dave