Re: [PATCH v3 2/7] selftests/ima: define a set of common functions

From: Petr Vorel
Date: Mon Mar 11 2019 - 17:39:34 EST


Hi Mimi,

> Define, update and move get_secureboot_mode() to a common file for use
> by other tests.

> Updated to check both the efivar SecureBoot-$(UUID) and
> SetupMode-$(UUID), based on Dave Young's review.

> Signed-off-by: Mimi Zohar <zohar@xxxxxxxxxxxxx>
> Reviewed-by: Petr Vorel <pvorel@xxxxxxx>
> Cc: Dave Young <dyoung@xxxxxxxxxx>

Minor comment below.

...
> +++ b/tools/testing/selftests/ima/ima_common_lib.sh
> @@ -0,0 +1,36 @@
> +#!/bin/sh
> +# SPDX-License-Identifier: GPL-2.0
> +
> +# Check efivar SecureBoot-$(the UUID) and SetupMode-$(the UUID).
> +# The secure boot mode can be accessed either as the last integer
> +# of "od -An -t u1 /sys/firmware/efi/efivars/SecureBoot-*" or from
> +# "od -An -t u1 /sys/firmware/efi/vars/SecureBoot-*/data". The efi
> +# SetupMode can be similarly accessed.
> +# Return 1 for SecureBoot mode enabled and SetupMode mode disabled.
> +get_secureboot_mode()
> +{
> + local efivarfs="/sys/firmware/efi/efivars"
> + local secure_boot_file=$efivarfs/../vars/SecureBoot-*/data
> + local setup_mode_file=$efivarfs/../vars/SetupMode-*/data
Sorry for nitpicking, but also quote variables these two variables
containing string:
local secure_boot_file="$efivarfs/../vars/SecureBoot-*/data"
local setup_mode_file="$efivarfs/../vars/SetupMode-*/data"

> + local secureboot_mode=0
> + local setup_mode=0
> +
> + # Make sure that efivars is mounted in the normal location
> + if ! grep -q "^\S\+ $efivarfs efivarfs" /proc/mounts; then
> + log_skip "efivars is not mounted on $efivarfs"
> + fi
> +
> + if [ ! -e $secure_boot_file ] || [ ! -e $setup_mode_file ]; then
I prefer to quote every variable in [ ] (at least for -f -e -z -n,
to prevent shell behavior on empty (I know it's not necessary here):

f=; [ -e $f ]; echo $?
0
vs.
f=; [ -e "$f" ]; echo $?
1


Kind regards,
Petr