improve applicability of rule package_rear_installed

[vojtapolasek]

Description:

Create appropriate platforms to fullfill the following:
Make the rule not applicable in following cases:

• arch is s390x and RHEL <= 8.4
• arch is aarch64 and RHEL or OL >= 9.0

Rationale:

• the rear package is not available on some arches and RHEL / OL versions

Review Hints:

• build the content
• instantiate some RHEL (OL) machine on s390x / aarch64 machine
• test that OVALs are applicable / not applicable in correct cases
• do the same with Ansible - you can use the e8 Ansible playbook with --tag=package_rear_installed
• tip: modify the /etc/os-release version_id line to simulate various distro versions

[github-actions]

Start a new ephemeral environment with changes proposed in this pull request:

Fedora Environment

Oracle Linux 8 Environment

[jan-cerny]

I think that the generated if condition in the Bash code isn't complete:

if ! ( ( ( grep -q aarch64 /proc/sys/kernel/osrelease ) || ( grep -q aarch64 /proc/sys/kernel/osrelease ) || ( grep -q s390x /proc/sys/kernel/osrelease ) ) ); then

[vojtapolasek]

@jan-cerny you are unfortunately correct. And there is not much we can do about it right now because we do not have proven way how to compare versions in Bash conditionals so far. Currently, Ansible conditionals will work correctly - you can test it. Bash conditionals won't. I know this is inconsistency and we plan to address it in the future. But at the other hand, Bash remediations should be used with oscap xccdf eval --remediate (or when generated from test results). They should not be blindly used as standalone playbooks and if someone decides to do so, they should review it. Any ideas or proposals for this problem? @yuumasato @matejak