openssl_* modules: private key errors (#54088)

* Improve error handling, in particular with respect to private key loading problems.

* Add tests to validate that modules regenerate invalid input and don't crash.

* Don't crash when input is invalid.

* Create 'better' broken input.

* Fix paths.

* Simplifying pyOpenSSL error handling.

test/integration/targets/openssl_dhparam/tasks/main.yml

@@ -1,3 +1,4 @@
+---
 - block:
     # This module generates unsafe parameters for testing purposes
     # otherwise tests would be too slow
@@ -41,4 +42,15 @@
         force: yes
       register: dhparam_changed_force
 
+    - name: Create broken params
+      copy:
+        dest: "{{ output_dir }}/dhbroken.pem"
+        content: "broken"
+    - name: Regenerate broken params
+      openssl_dhparam:
+        path: '{{ output_dir }}/dhbroken.pem'
+        size: 512
+        force: yes
+      register: output_broken
+
     - import_tasks: ../tests/validate.yml

test/integration/targets/openssl_dhparam/tests/validate.yml

@@ -30,3 +30,8 @@
       - dhparam_changed_512 is not changed
       - dhparam_changed_to_512 is changed
       - dhparam_changed_force is changed
+
+- name: Verify that broken params will be regenerated
+  assert:
+    that:
+      - output_broken is changed