Use BIND 9 server instead of Cloudfl. for DNS-01 challenge via nsupdate

Co-authored-by: Jannik Beyerstedt <code@jannikbeyerstedt.de>

playbooks/roles/cert/README.md

@@ -0,0 +1,24 @@
+# Role `cert`
+
+A role for ordering and renewing certificates from Lets Encrypt via ACME.
+It uses the DNS challenge and fullfills it via a BIND 9 server given to the role.
+
+## Supported Distributions
+
+The following distributions are supported:
+
+- Debian 11
+
+## Required Arguments
+
+For the required arguments look at the [`argument_specs.yaml`](./meta/argument_specs.yml)
+
+## `hosts`
+
+The `hosts` for this role need to be the machines on which you want to have the certificates.
+
+## Links & Resources
+
+- <https://docs.ansible.com/ansible/7/collections/community/crypto/acme_certificate_module.html>
+- <https://docs.ansible.com/ansible/7/collections/community/crypto/openssl_privatekey_module.html>
+- <https://docs.ansible.com/ansible/7/collections/community/crypto/openssl_csr_module.html>

playbooks/roles/cert/meta/argument_specs.yml

@@ -22,16 +22,11 @@ argument_specs:
         description: E-Mail address for ACME account
         required: true
         type: str
-      cert__cloudflare_dns:
-        description: Cloudflare DNS API details
+      cert__bind_9_host:
+        description: The machine running BIND 9.
         required: true
-        type: dict
-        options:
-          api_token:
-            description: Cloudflare API token
-            required: true
-            type: str
-          zone:
-            description: DNS zone the domain is in
-            required: true
-            type: str
+        type: str
+      cert__bind_9_zone:
+        description: The zone to use for publishing the TXT record.
+        required: true
+        type: str

playbooks/roles/cert/tasks/deploy_cert.yml

@@ -74,17 +74,22 @@
 - name: Retrieve certificate and fulfill challenge if needed # noqa no-handler
   when: cert__acme_challenge.changed # Can't be put in a handler, because then the block "always" tasks won't be executed for some reason
   block:
-    - name: Set DNS record via Cloudflare API to fulfill the challenge
-      when: not cert__acme_challenge.authorizations[item].status == "valid"
-      community.general.cloudflare_dns:
-        api_token: "{{ cert__cloudflare_dns.api_token }}"
-        zone: "{{ cert__cloudflare_dns.zone }}"
-        record: "{{ cert__acme_challenge.challenge_data[item]['dns-01'].record }}"
-        value: "{{ cert__acme_challenge.challenge_data[item]['dns-01'].resource_value }}"
-        type: TXT
-        ttl: 60
-        solo: true
-        state: present
+    - name: Add file containing nsupdate commands for adding TXT record for DNS-01 challenge
+      ansible.builtin.template:
+        src: nsupdate_add_txt_record.j2
+        dest: /root/nsupdate_add_txt_record
+        owner: root
+        group: root
+        mode: "0600"
+      vars:
+        cert__nsupdate_domain: "{{ cert__acme_challenge.challenge_data[item]['dns-01'].record }}"
+        cert__nsupdate_txt_data: "{{ cert__acme_challenge.challenge_data[item]['dns-01'].resource_value }}"
+      delegate_to: "{{ cert__bind_9_host }}"
+
+    - name: Add DNS record to BIND 9 server via nsupdate  # noqa: no-changed-when
+      ansible.builtin.command: /usr/bin/nsupdate -l /root/nsupdate_add_txt_record
+      delegate_to: "{{ cert__bind_9_host }}"
+
     - name: Retrieve certificate
       community.crypto.acme_certificate:
         account_email: "{{ cert__acme_account_email }}"
@@ -101,16 +106,35 @@
       become: true
       notify: "{{ cert__handlers }}"
   always:
-    - name: Ensure DNS record is removed
-      when: not cert__acme_challenge.authorizations[item].status == "valid"
-      community.general.cloudflare_dns:
-        api_token: "{{ cert__cloudflare_dns.api_token }}"
-        zone: "{{ cert__cloudflare_dns.zone }}"
-        record: "{{ cert__acme_challenge.challenge_data[item]['dns-01'].record }}"
-        value: "{{ cert__acme_challenge.challenge_data[item]['dns-01'].resource_value }}"
-        type: TXT
-        ttl: 60
+    - name: Remove file containing nsupdate commands for adding TXT record again
+      ansible.builtin.file:
+        path: /root/nsupdate_add_txt_record
         state: absent
+      delegate_to: "{{ cert__bind_9_host }}"
+
+    - name: Remove TXT record again
+      block:
+        - name: Add file containing nsupdate commands for deleting TXT record for DNS-01 challenge
+          ansible.builtin.template:
+            src: nsupdate_delete_txt_record.j2
+            dest: /root/nsupdate_delete_txt_record
+            owner: root
+            group: root
+            mode: "0600"
+          vars:
+            cert__nsupdate_domain: "{{ cert__acme_challenge.challenge_data[item]['dns-01'].record }}"
+            cert__nsupdate_txt_data: "{{ cert__acme_challenge.challenge_data[item]['dns-01'].resource_value }}"
+          delegate_to: "{{ cert__bind_9_host }}"
+
+        - name: Remove DNS record from BIND 9 server via nsupdate  # noqa: no-changed-when
+          ansible.builtin.command: /usr/bin/nsupdate -l /root/nsupdate_delete_txt_record
+          delegate_to: "{{ cert__bind_9_host }}"
+      always:
+        - name: Remove file containing nsupdate commands for deleting TXT record again
+          ansible.builtin.file:
+            path: /root/nsupdate_delete_txt_record
+            state: absent
+          delegate_to: "{{ cert__bind_9_host }}"
 
 - name: Ensure correct permissions for certificate are set
   ansible.builtin.file:

playbooks/roles/cert/templates/nsupdate_add_txt_record.j2

@@ -0,0 +1,4 @@
+debug
+zone {{ cert__bind_9_zone }}
+update add {{ cert__nsupdate_domain }} 60 TXT {{ cert__nsupdate_txt_data }}
+send

playbooks/roles/cert/templates/nsupdate_delete_txt_record.j2

@@ -0,0 +1,4 @@
+debug
+zone {{ cert__bind_9_zone }}
+update delete {{ cert__nsupdate_domain }} 60 TXT {{ cert__nsupdate_txt_data }}
+send