ansible-hardening/tasks/auditd.yml

---
# Copyright 2015, Rackspace US, Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

#TODO(evrardjp): Replace the next 2 tasks by a standard apt with cache
#when https://github.com/ansible/ansible-modules-core/pull/1517 is merged
#in 1.9.x or we move to 2.0 (if tested working)
- name: Check apt last update file
  stat:
    path: /var/cache/apt
  register: apt_cache_stat
  tags:
    - auditd-apt-packages

- name: Update apt if needed
  apt:
    update_cache: yes
  when: "ansible_date_time.epoch|float - apt_cache_stat.stat.mtime > {{cache_timeout}}"
  tags:
    - auditd-apt-packages

- name: V-38631/38632 - The operating system must produce audit records (install auditd)
  apt:
    name: auditd
    state: present
  tags:
    - auditd
    - cat2
    - V-38632
    - V-38631

- name: V-38631/38632 - The operating system must produce audit records (start auditd)
  service:
    name: auditd
    state: started
    enabled: true
  when: not check_mode
  tags:
    - auditd
    - cat2
    - V-38632
    - V-38631

- name: Verify that auditd.conf exists
  stat:
    path: /etc/audit/auditd.conf
  register: auditd_conf
  always_run: true
  tags:
    - auditd
    - always

- name: V-38633 - The system must set a maximum audit log file size
  lineinfile:
    dest: /etc/audit/auditd.conf
    regexp: "^(#)?max_log_file ="
    line: "max_log_file = {{ max_log_file }}"
  when: auditd_conf.stat.exists | bool
  notify:
    - restart auditd
  tags:
    - auditd
    - cat2
    - V-38633

- name: V-38634 - The system must rotate audit log files that reach the max file size
  lineinfile:
    dest: /etc/audit/auditd.conf
    regexp: "^(#)?max_log_file_action ="
    line: "max_log_file_action = {{ max_log_file_action }}"
  when: auditd_conf.stat.exists | bool
  notify:
    - restart auditd
  tags:
    - auditd
    - cat2
    - V-38634

- name: V-38636 - The system must retain enough rotated audit logs to cover the required log retention period.
  lineinfile:
    dest: /etc/audit/auditd.conf
    regexp: "^(#)?num_logs ="
    line: "num_logs = {{ num_logs }}"
  when: auditd_conf.stat.exists | bool
  notify:
    - restart auditd
  tags:
    - auditd
    - cat2
    - V-38636

- name: Ensure debsums package is installed (for V-38637)
  apt:
    name: debsums
    state: present
  tags:
    - auditd
    - cat2
    - V-38637

# The debsums command returns 0 if the files haven't been altered but it
# returns 2 otherwise. We also will check to see if auditd has been installed
# and fail if it's not installed.
- name: Checking auditd package contents for alterations with debsums (for V-38637)
  shell: debsums auditd -c
  register: v38637_result
  changed_when: False
  failed_when: "'not installed' in v38637_result.stdout"
  tags:
    - auditd
    - cat2
    - V-38637

- name: V-38637 - Contents of auditd package must be verified
  fail:
    msg: "FAILED: Could not verify that files from auditd package are unaltered"
  when: not check_mode and v38637_result.rc == 2
  tags:
    - auditd
    - cat2
    - V-38637

- name: Verify that auditd log directory exists (for V-38445)
  stat:
    path: /var/log/audit/
  register: auditd_log_dir
  always_run: True
  tags:
    - auditd
    - always

- name: V-38445 - Audit log files must be group-owned by root
  file:
    dest: /var/log/audit/
    group: root
    recurse: true
  when: auditd_log_dir.stat.exists | bool
  tags:
    - auditd
    - cat2
    - V-38445

- name: V-38464 - The audit system must take action for disk errors
  lineinfile:
    dest: /etc/audit/auditd.conf
    regexp: "^(#)?disk_error_action"
    line: "disk_error_action = {{ disk_error_action }}"
  when: auditd_conf.stat.exists | bool
  notify:
    - restart auditd
  tags:
    - auditd
    - cat2
    - V-38464

- name: V-38468 - The audit system must take action when the disk is full
  lineinfile:
    dest: /etc/audit/auditd.conf
    regexp: "^(#)?disk_full_action"
    line: "disk_full_action = {{ disk_full_action }}"
  when: auditd_conf.stat.exists | bool
  notify:
    - restart auditd
  tags:
    - auditd
    - cat2
    - V-38468

- name: V-38678 - Lower limit of available disk space when auditd triggers space_left_action
  lineinfile:
    dest: /etc/audit/auditd.conf
    regexp: "^(#)?space_left"
    line: "space_left = {{ space_left }}"
  when: auditd_conf.stat.exists | bool
  notify:
    - restart auditd
  tags:
    - auditd
    - cat2
    - V-38678

- name: V-38470 - The audit system must take action when the disk is almost full
  lineinfile:
    dest: /etc/audit/auditd.conf
    regexp: "^(#)?space_left_action"
    line: "space_left_action = {{ space_left_action }}"
  when: auditd_conf.stat.exists | bool
  notify:
    - restart auditd
  tags:
    - auditd
    - cat2
    - V-38470

- name: V-38680 - Audit system must send email notifications when storage capacity is low
  lineinfile:
    dest: /etc/audit/auditd.conf
    regexp: "^(#)?action_mail_acct"
    line: "action_mail_acct = {{ action_mail_acct }}"
  when: auditd_conf.stat.exists | bool
  notify:
    - restart auditd
  tags:
    - auditd
    - cat2
    - V-38680

- name: V-38495 - Audit log files must be owned by root
  file:
    dest: /var/log/audit/
    owner: root
    recurse: true
  when: auditd_log_dir.stat.exists | bool
  tags:
    - auditd
    - cat2
    - V-38495

# TODO: Ansible 2.0 offers the find module and that will allow this task to
# avoid using the shell module to get a list of logs. This task should be
# adjusted to use the find module when Ansible 2.0 is fully released.
- name: Get a list of audit logs in the auditd directory (for V-38498)
  shell: ls /var/log/audit/
  register: v38498_result
  changed_when: false
  tags:
    - auditd
    - cat2
    - V-38498

# Ubuntu 14.04 sets these to 0400 by default, so we will stick with that since
# it exceeds the STIG's requirements.
- name: V-38498 - Audit log files must have mode 0640 or less
  file:
    dest: "/var/log/audit/{{ item }}"
    mode: 0400
  with_items: v38498_result.stdout_lines
  when: v_38498_result is defined
  tags:
    - auditd
    - cat2
    - V-38498

- name: Auditd rules (includes several STIGs)
  template:
    src: osas-auditd.j2
    dest: /etc/audit/rules.d/osas-auditd.rules
  notify:
    - generate auditd rules
  tags:
    - auditd
    - cat3

- name: V-38471 - Forward auditd records to syslog
  lineinfile:
    dest: /etc/audisp/plugins.d/syslog.conf
    regexp: "^(#)?active"
    line: "active = yes"
    state: present
  when: auditd_conf.stat.exists | bool
  notify:
    - restart auditd
  tags:
    - auditd
    - cat3
    - V-38471

- name: V-54381 - The audit system must switch to single user mode when disk space is low
  lineinfile:
    dest: /etc/audit/auditd.conf
    regexp: "^(#)?admin_space_left_action"
    line: "admin_space_left_action = {{ admin_space_left_action }}"
  when: auditd_conf.stat.exists | bool
  notify:
    - restart auditd
  tags:
    - auditd
    - cat2
    - V-54381