# platform = multi_platform_all
# reboot = true
# strategy = disable
# complexity = low
# disruption = medium
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-39
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_user_max_user_namespaces

- name: Disable the use of user namespaces - Set fact for sysctl paths
  ansible.builtin.set_fact:
    sysctl_paths:
    - /etc/sysctl.d/
    - /run/sysctl.d/
    - /usr/local/lib/sysctl.d/
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-39
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_user_max_user_namespaces

- name: Disable the use of user namespaces - Find all files that contain user.max_user_namespaces
  ansible.builtin.shell:
    cmd: find -L {{ sysctl_paths | join(" ") }} -type f -name '*.conf' | xargs grep
      -HP '^\s*user.max_user_namespaces\s*=\s*.*$'
  register: find_all_values
  check_mode: false
  changed_when: false
  failed_when: false
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-39
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_user_max_user_namespaces

- name: Disable the use of user namespaces - Find all files that set user.max_user_namespaces
    to correct value
  ansible.builtin.shell:
    cmd: find -L {{ sysctl_paths | join(" ") }} -type f -name '*.conf' | xargs grep
      -HP '^\s*user.max_user_namespaces\s*=\s*0$'
  register: find_correct_value
  check_mode: false
  changed_when: false
  failed_when: false
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-39
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_user_max_user_namespaces

- name: Disable the use of user namespaces - Comment out any occurrences of user.max_user_namespaces
    from config files
  ansible.builtin.replace:
    path: '{{ item | split(":") | first }}'
    regexp: ^[\s]*user.max_user_namespaces
    replace: '#user.max_user_namespaces'
  loop: '{{ find_all_values.stdout_lines }}'
  when:
  - '"linux-base" in ansible_facts.packages'
  - find_correct_value.stdout_lines | length == 0 or find_all_values.stdout_lines
    | length > find_correct_value.stdout_lines | length
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-39
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_user_max_user_namespaces

- name: Disable the use of user namespaces - Comment out any occurrences of user.max_user_namespaces
    from /etc/ufw/sysctl.conf
  ansible.builtin.replace:
    path: /etc/ufw/sysctl.conf
    regexp: (^[\s]*user.max_user_namespaces.*$)
    replace: '# \1'
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-39
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_user_max_user_namespaces

- name: Disable the use of user namespaces - Ensure sysctl user.max_user_namespaces
    is set to 0
  ansible.posix.sysctl:
    name: user.max_user_namespaces
    value: '0'
    sysctl_file: /etc/sysctl.conf
    state: present
    reload: true
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-39
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_user_max_user_namespaces
