5.2.5. HOWTO Enable STIG Mode on a SIMP System

Enabling STIG mode in SIMP involves using The SIMP Compliance Engine to apply the STIG-specific SIMP compliance profile.

Like everything in Puppet, STIG-mode only applies to those nodes that actively include the correct settings.

5.2.5.1. Assumptions

1. You have a fully functional SIMP system up and running per the instructions in Installation Options.

2. The FQDN of your node is stig.your.domain and that you only want to enable STIG mode for this node. You can use Hiera to enable it for all nodes if you so choose.

3. You are using the production Puppet Environment

4. You have a regular user named stiguser that will be used for remote access to your system and for escalation of privileges to root. This is due to the fact that, by default, SIMP does not allow remote root access.

5.2.5.2. Setting up Hiera

First, we need to create the file /etc/puppetlabs/code/environments/production/data/hosts/stig.your.domain.yaml. The next few sections describe what should be added to this file to ensure that STIG mode will be activated and that your user can properly login to the system.

5.2.5.2.1. Allowing stiguser to login

pam::access::users:
  stiguser:
    origins:
      - ALL

5.2.5.2.2. Allow stiguser to escalate to root

sudo::user_specifications:
  stiguser_su:
    user_list:
      - stiguser
    cmnd:
      - ALL
    # You should change this to 'true' for full STIG compliance
    # Ensure that you have a working password set first!
    passwd: false
    options:
      # Required for seamless root sudo commands
      role: unconfined_r

5.2.5.2.3. Configure selinux to allow stiguser to run privileged commands

selinux::login_resources:
  stiguser:
    seuser: staff_u
    mls_range: "s0-s0:c0.c1023"

5.2.5.2.4. Place the system in STIG-enforcing mode

Now that you have ensured that stiguser can access your system as well as escalate to an administrative user without being blocked by SELinux, you are ready to enable STIG-enforcing mode.

First, include the SIMP Compliance Engine backend in the hierarchy defined in the environments hiera.yaml, /etc/puppetlabs/code/environments/production/hiera.yaml. Place it under the hierarchy tag just before default:

---
version: 5
defaults:
  datadir: data
  data_hash: yaml_data

hierarchy:

...

- name: SIMP Compliance Engine
  lookup_key: compliance_markup::enforcement

- name: General data
  paths:
  - "default.yaml"
  - "common.yaml"

...

Then add the following to the stig.your.domain.yaml file that we have been editing:

compliance_markup::enforcement:
  - disa_stig

5.2.5.3. Next Steps

5.2.5.3.1. Applying the changes

At this point, your system is ready to apply the STIG enforcement settings. To begin enforcement, simply run puppet agent -t on the stig.your.domain node or wait for the next scheduled run of puppet.

5.2.5.3.2. Escalating privileges

Remote system access should work as you would expect but there is a new caveat to how you would normally run sudo to access the root account.

Since the STIG requires that all users be in an SELinux context, you will need to ensure that all administrative users are staff_u users as we did above.

Once this is complete, you must tell sudo what context you wish to transition into when running commands.

The simplest invocation is as follows:

[stiguser@localhost ~]$ sudo su - root

For additional information see the vendor documentation on confined and unconfined users and/or Dan Walsh’s blog.