Not sure how many people will find this helpful, but wanted to share my documentation for toggling firewall rules via Home Assistant.

https://gist.github.com/zyphermonkey/bb039afa3d382389c60c4d3a0200efb4

Toggle OPNsense Firewall Rule via Home Assistant (HASS)

OPNsense

Create Account for HASS to authenticate with

System > Access > Users

Create account in opnsense with All pages privileges
Click Create and download API key for this user
Create basic auth string for use with cURL.
1. combine key:secret
2. base64 encode
3. prefix with "Basic "

Validate auth string via simple curl command

curl -k https://192.168.1.1/api/core/system/status \
-H "Authorization: $AUTH_STRING"

Create Alias

For my scenario I want to block a specific MAC so I got it via the DHCP Leases page.
Services>ISC DHCPv4[legacy]>Leases

Go to Firewall > Aliases > New
Info
- Enabled: checked
- Name: <Hostname>
  This can be anything you want, but I set it to the Hostname because it makes the most sense.
- Type: MAC address
- Content: <mac_address_recorded_from_leases_page>
Apply

Create Firwall Rule

If you don't already have a rule you want to toggle of if you want to create one just for initial testing with HASS.

Go to Firewall > Rules[new]
Create whatever

Get Firewall Rule UUID

Go to Firewall > Rules[new]
Open Browers developer tools (F12)
Click edit on rule
The latest line in the Network tab in Developer Tools should be a GET request to /api/firewall/filter/get_rule/<uuid>
1. Record uuid for use in HASS commands

Home Assistant (HASS)

Create opnsense auth var in secrets.yaml`

Open secrets.yaml and create new variable with base64 encoded api key from OPNsense.
```
opnsense_api_auth: "Basic &lt;base64_encoded key:secret&gt;"
```

Create sensor

Home Assistant needs to be able to know the current state of the firewall rule to effectively toggle it (and show it's status on dashboards).

configuration.yaml

sensor:
  - platform: rest
    name: opnsense_fw_rule_state_yourrulenamehere
    resource: https://192.168.1.1/api/firewall/filter/get_rule/&lt;uuid&gt;
    method: GET
    value_template: "{{ value_json.rule.enabled }}"
    headers:
      Authorization: !secret opnsense_api_auth
    verify_ssl: false

Create switch template & rest commands

Create switch template in configuration.yaml

template:
  - switch:
      - name: internet_access_yourrulenamehere
        unique_id: internet_access_yourrulenamehere
        state: "{{ is_state('sensor.opnsense_fw_rule_state_yourrulenamehere', '1') }}"
        turn_on:
          service: rest_command.opnsense_rule_on_yourrulenamehere
        turn_off:
          service: rest_command.opnsense_rule_off_yourrulenamehere

Create rest commands (apply, enable, disable) in configuration.yaml

rest_command:
  opnsense_apply:
    url: https://192.168.1.1/api/firewall/filter/apply
    method: POST
    headers:
      Authorization: !secret opnsense_api_auth
    verify_ssl: false

  opnsense_rule_on_yourrulenamehere:
    url: https://192.168.1.1/api/firewall/filter/toggle_rule/&lt;uuid&gt;/1
    method: POST
    headers:
      Authorization: !secret opnsense_api_auth
    verify_ssl: false

  opnsense_rule_off_yourrulenamehere:
    url: https://192.168.1.1/api/firewall/filter/toggle_rule/&lt;uuid&gt;/0
    method: POST
    headers:
      Authorization: !secret opnsense_api_auth
    verify_ssl: false

Validate

Ensure changes maded to secrets.yaml and configuration.yaml are stable check your configuration after saving.

Settings > Developer tools > Check configuration

Use in your dashboards/automations

You should now be able to add the switch and sensor to your dashboards with the following:

entity: switch.internet_access_yourrulenamehere
entity: sensor.opnsense_fw_rule_state_yourrulenamehere

u/zyphermonkey

[HOW TO] Toggle OPNsense Firewall Rule via Home Assistant (HASS)