Chapter 37. Ensuring the presence of host-based access control rules in IdM using Ansible playbooks

This chapter describes Identity Management (IdM) host-based access policies and how to define them using Ansible.

Ansible is an automation tool used to configure systems, deploy software, and perform rolling updates. It includes support for Identity Management (IdM).

37.1. Host-based access control rules in IdM

Host-based access control (HBAC) rules define which users or user groups can access which hosts or host groups by using which services or services in a service group. As a system administrator, you can use HBAC rules to achieve the following goals:

  • Limit access to a specified system in your domain to members of a specific user group.
  • Allow only a specific service to be used to access systems in your domain.

By default, IdM is configured with a default HBAC rule named allow_all, which means universal access to every host for every user via every relevant service in the entire IdM domain.

You can fine-tune access to different hosts by replacing the default allow_all rule with your own set of HBAC rules. For centralized and simplified access control management, you can apply HBAC rules to user groups, host groups, or service groups instead of individual users, hosts, or services.

37.2. Ensuring the presence of an HBAC rule in IdM using an Ansible playbook

This section describes how to ensure the presence of a host-based access control (HBAC) rule in Identity Management (IdM) using an Ansible playbook.

Prerequisites

Procedure

  1. Create an inventory file, for example inventory.file, and define ipaserver in it: 

    [ipaserver]
server.idm.example.com

  2. Create your Ansible playbook file that defines the HBAC policy whose presence you want to ensure. To simplify this step, you can copy and modify the example in the /usr/share/doc/ansible-freeipa/playbooks/hbacrule/ensure-hbacrule-allhosts-present.yml file: 

    ---
- name: Playbook to handle hbacrules
  hosts: ipaserver
  become: true

  tasks:
  # Ensure idm_user can access client.idm.example.com via the sshd service
  - ipahbacrule:
      ipaadmin_password: MySecret123
      name: login
      user: idm_user
      host: client.idm.example.com
      hbacsvc:
      - sshd
      state: present

  3. Run the playbook: 

    $ ansible-playbook -v -i path_to_inventory_directory/inventory.file path_to_playbooks_directory/ensure-new-hbacrule-present.yml

Verification steps

  1. Log in to the IdM Web UI as administrator.
  2. Navigate to Policy → Host-Based-Access-Control → HBAC Test.
  3. In the Who tab, select idm_user.
  4. In the Accessing tab, select client.idm.example.com.
  5. In the Via service tab, select sshd.
  6. In the Rules tab, select login.
  7. In the Run test tab, click the Run test button. If you see ACCESS GRANTED, the HBAC rule is implemented successfully.

Additional resources

  • For more details about and examples of, configuring HBAC services, service groups, and rules using Ansible, see the README-hbacsvc.md, README-hbacsvcgroup.md, and README-hbacrule.md Markdown files. These files are available in the /usr/share/doc/ansible-freeipa directory. Also see the playbooks available in the relevant subdirectories of the /usr/share/doc/ansible-freeipa/playbooks directory.