luks_device: add basic check mode (#54477)

* Add basic check mode.

* One more early exit.

* Fix naming.

* Check that device is actually an existing device.

lib/ansible/modules/crypto/luks_device.py

@@ -101,13 +101,6 @@ requirements:
     - "wipefs"
     - "lsblk"
 
-notes:
-    - "This module does not support check mode. The reason being that
-      while it is possible to chain several operations together
-      (e.g. 'create' and 'open'), the latter usually depends on changes
-      to the system done by the previous one. (LUKS cannot be opened,
-      when it does not exist.)"
-
 author:
     "Jan Pokorny (@japokorn)"
 '''
@@ -172,7 +165,9 @@ name:
     sample: "luks-c1da9a58-2fde-4256-9d9f-6ab008b4dd1b"
 '''
 
+import os
 import re
+import stat
 
 from ansible.module_utils.basic import AnsibleModule
 
@@ -249,7 +244,7 @@ class CryptHandler(Handler):
         return device
 
     def is_luks(self, device):
-        ''' check if the LUKS device does exist
+        ''' check if the LUKS container does exist
         '''
         result = self._run_command([self._cryptsetup_bin, 'isLuks', device])
         return result[RETURN_CODE] == 0
@@ -464,7 +459,16 @@ def run_module():
     )
 
     module = AnsibleModule(argument_spec=module_args,
-                           supports_check_mode=False)
+                           supports_check_mode=True)
+
+    if module.params['device'] is not None:
+        try:
+            statinfo = os.stat(module.params['device'])
+            mode = statinfo.st_mode
+            if not stat.S_ISBLK(mode) and not stat.S_ISCHR(mode):
+                raise Exception('{0} is not a device'.format(module.params['device']))
+        except Exception as e:
+            module.fail_json(msg=str(e))
 
     crypt = CryptHandler(module)
     conditions = ConditionsHandler(module, crypt)
@@ -474,12 +478,15 @@ def run_module():
 
     # luks create
     if conditions.luks_create():
+        if not module.check_mode:
             try:
                 crypt.run_luks_create(module.params['device'],
                                       module.params['keyfile'])
             except ValueError as e:
                 module.fail_json(msg="luks_device error: %s" % e)
         result['changed'] = True
+        if module.check_mode:
+            module.exit_json(**result)
 
     # luks open
 
@@ -494,6 +501,7 @@ def run_module():
                 name = crypt.generate_luks_name(module.params['device'])
             except ValueError as e:
                 module.fail_json(msg="luks_device error: %s" % e)
+        if not module.check_mode:
             try:
                 crypt.run_luks_open(module.params['device'],
                                     module.params['keyfile'],
@@ -502,6 +510,8 @@ def run_module():
                 module.fail_json(msg="luks_device error: %s" % e)
         result['name'] = name
         result['changed'] = True
+        if module.check_mode:
+            module.exit_json(**result)
 
     # luks close
     if conditions.luks_close():
@@ -513,14 +523,18 @@ def run_module():
                 module.fail_json(msg="luks_device error: %s" % e)
         else:
             name = module.params['name']
+        if not module.check_mode:
             try:
                 crypt.run_luks_close(name)
             except ValueError as e:
                 module.fail_json(msg="luks_device error: %s" % e)
         result['changed'] = True
+        if module.check_mode:
+            module.exit_json(**result)
 
     # luks add key
     if conditions.luks_add_key():
+        if not module.check_mode:
             try:
                 crypt.run_luks_add_key(module.params['device'],
                                        module.params['keyfile'],
@@ -528,9 +542,12 @@ def run_module():
             except ValueError as e:
                 module.fail_json(msg="luks_device error: %s" % e)
         result['changed'] = True
+        if module.check_mode:
+            module.exit_json(**result)
 
     # luks remove key
     if conditions.luks_remove_key():
+        if not module.check_mode:
             try:
                 crypt.run_luks_remove_key(module.params['device'],
                                           module.params['remove_keyfile'],
@@ -538,14 +555,19 @@ def run_module():
             except ValueError as e:
                 module.fail_json(msg="luks_device error: %s" % e)
         result['changed'] = True
+        if module.check_mode:
+            module.exit_json(**result)
 
     # luks remove
     if conditions.luks_remove():
+        if not module.check_mode:
             try:
                 crypt.run_luks_remove(module.params['device'])
             except ValueError as e:
                 module.fail_json(msg="luks_device error: %s" % e)
         result['changed'] = True
+        if module.check_mode:
+            module.exit_json(**result)
 
     # Success - return result
     module.exit_json(**result)

test/integration/targets/luks_device/tasks/tests/create-destroy.yml

@@ -1,12 +1,12 @@
 ---
-#- name: Create (check)
-#  luks_device:
-#    device: "{{ cryptfile_device }}"
-#    state: present
-#    keyfile: "{{ role_path }}/files/keyfile1"
-#  check_mode: yes
-#  become: yes
-#  register: create_check
+- name: Create (check)
+  luks_device:
+    device: "{{ cryptfile_device }}"
+    state: present
+    keyfile: "{{ role_path }}/files/keyfile1"
+  check_mode: yes
+  become: yes
+  register: create_check
 - name: Create
   luks_device:
     device: "{{ cryptfile_device }}"
@@ -21,29 +21,29 @@
     keyfile: "{{ role_path }}/files/keyfile1"
   become: yes
   register: create_idem
-#- name: Create (idempotent, check)
-#  luks_device:
-#    device: "{{ cryptfile_device }}"
-#    state: present
-#    keyfile: "{{ role_path }}/files/keyfile1"
-#  check_mode: yes
-#  become: yes
-#  register: create_idem_check
+- name: Create (idempotent, check)
+  luks_device:
+    device: "{{ cryptfile_device }}"
+    state: present
+    keyfile: "{{ role_path }}/files/keyfile1"
+  check_mode: yes
+  become: yes
+  register: create_idem_check
 - assert:
     that:
-    #- create_check is changed
+    - create_check is changed
     - create is changed
     - create_idem is not changed
-    #- create_idem_check is not changed
+    - create_idem_check is not changed
 
-#- name: Open (check)
-#  luks_device:
-#    device: "{{ cryptfile_device }}"
-#    state: opened
-#    keyfile: "{{ role_path }}/files/keyfile1"
-#  check_mode: yes
-#  become: yes
-#  register: open_check
+- name: Open (check)
+  luks_device:
+    device: "{{ cryptfile_device }}"
+    state: opened
+    keyfile: "{{ role_path }}/files/keyfile1"
+  check_mode: yes
+  become: yes
+  register: open_check
 - name: Open
   luks_device:
     device: "{{ cryptfile_device }}"
@@ -58,28 +58,28 @@
     keyfile: "{{ role_path }}/files/keyfile1"
   become: yes
   register: open_idem
-#- name: Open (idempotent, check)
-#  luks_device:
-#    device: "{{ cryptfile_device }}"
-#    state: opened
-#    keyfile: "{{ role_path }}/files/keyfile1"
-#  check_mode: yes
-#  become: yes
-#  register: open_idem_check
+- name: Open (idempotent, check)
+  luks_device:
+    device: "{{ cryptfile_device }}"
+    state: opened
+    keyfile: "{{ role_path }}/files/keyfile1"
+  check_mode: yes
+  become: yes
+  register: open_idem_check
 - assert:
     that:
-    #- open_check is changed
+    - open_check is changed
     - open is changed
     - open_idem is not changed
-    #- open_idem_check is not changed
+    - open_idem_check is not changed
 
-#- name: Closed (via name, check)
-#  luks_device:
-#    name: "{{ open.name }}"
-#    state: closed
-#  check_mode: yes
-#  become: yes
-#  register: close_check
+- name: Closed (via name, check)
+  luks_device:
+    name: "{{ open.name }}"
+    state: closed
+  check_mode: yes
+  become: yes
+  register: close_check
 - name: Closed (via name)
   luks_device:
     name: "{{ open.name }}"
@@ -92,19 +92,19 @@
     state: closed
   become: yes
   register: close_idem
-#- name: Closed (via name, idempotent, check)
-#  luks_device:
-#    name: "{{ open.name }}"
-#    state: closed
-#  check_mode: yes
-#  become: yes
-#  register: close_idem_check
+- name: Closed (via name, idempotent, check)
+  luks_device:
+    name: "{{ open.name }}"
+    state: closed
+  check_mode: yes
+  become: yes
+  register: close_idem_check
 - assert:
     that:
-    #- close_check is changed
+    - close_check is changed
     - close is changed
     - close_idem is not changed
-    #- close_idem_check is not changed
+    - close_idem_check is not changed
 
 - name: Re-open
   luks_device:
@@ -113,13 +113,13 @@
     keyfile: "{{ role_path }}/files/keyfile1"
   become: yes
 
-#- name: Closed (via device, check)
-#  luks_device:
-#    device: "{{ cryptfile_device }}"
-#    state: closed
-#  check_mode: yes
-#  become: yes
-#  register: close_check
+- name: Closed (via device, check)
+  luks_device:
+    device: "{{ cryptfile_device }}"
+    state: closed
+  check_mode: yes
+  become: yes
+  register: close_check
 - name: Closed (via device)
   luks_device:
     device: "{{ cryptfile_device }}"
@@ -132,19 +132,19 @@
     state: closed
   become: yes
   register: close_idem
-#- name: Closed (via device, idempotent, check)
-#  luks_device:
-#    device: "{{ cryptfile_device }}"
-#    state: closed
-#  check_mode: yes
-#  become: yes
-#  register: close_idem_check
+- name: Closed (via device, idempotent, check)
+  luks_device:
+    device: "{{ cryptfile_device }}"
+    state: closed
+  check_mode: yes
+  become: yes
+  register: close_idem_check
 - assert:
     that:
-    #- close_check is changed
+    - close_check is changed
     - close is changed
     - close_idem is not changed
-    #- close_idem_check is not changed
+    - close_idem_check is not changed
 
 - name: Re-opened
   luks_device:
@@ -153,13 +153,13 @@
     keyfile: "{{ role_path }}/files/keyfile1"
   become: yes
 
-#- name: Absent (check)
-#  luks_device:
-#    device: "{{ cryptfile_device }}"
-#    state: absent
-#  check_mode: yes
-#  become: yes
-#  register: absent_check
+- name: Absent (check)
+  luks_device:
+    device: "{{ cryptfile_device }}"
+    state: absent
+  check_mode: yes
+  become: yes
+  register: absent_check
 - name: Absent
   luks_device:
     device: "{{ cryptfile_device }}"
@@ -172,16 +172,16 @@
     state: absent
   become: yes
   register: absent_idem
-#- name: Absent (idempotence, check)
-#  luks_device:
-#    device: "{{ cryptfile_device }}"
-#    state: absent
-#  check_mode: yes
-#  become: yes
-#  register: absent_idem_check
+- name: Absent (idempotence, check)
+  luks_device:
+    device: "{{ cryptfile_device }}"
+    state: absent
+  check_mode: yes
+  become: yes
+  register: absent_idem_check
 - assert:
     that:
-    #- absent_check is changed
+    - absent_check is changed
     - absent is changed
     - absent_idem is not changed
-    #- absent_idem_check is not changed
+    - absent_idem_check is not changed

test/integration/targets/luks_device/tasks/tests/device-check.yml

@@ -0,0 +1,48 @@
+---
+- name: Create with invalid device name (check)
+  luks_device:
+    device: /dev/asdfasdfasdf
+    state: present
+    keyfile: "{{ role_path }}/files/keyfile1"
+  check_mode: yes
+  ignore_errors: yes
+  become: yes
+  register: create_check
+- name: Create with invalid device name
+  luks_device:
+    device: /dev/asdfasdfasdf
+    state: present
+    keyfile: "{{ role_path }}/files/keyfile1"
+  ignore_errors: yes
+  become: yes
+  register: create
+- assert:
+    that:
+      - create_check is failed
+      - create is failed
+      - "'o such file or directory' in create_check.msg"
+      - "'o such file or directory' in create.msg"
+
+- name: Create with something which is not a device (check)
+  luks_device:
+    device: /tmp/
+    state: present
+    keyfile: "{{ role_path }}/files/keyfile1"
+  check_mode: yes
+  ignore_errors: yes
+  become: yes
+  register: create_check
+- name: Create with something which is not a device
+  luks_device:
+    device: /tmp/
+    state: present
+    keyfile: "{{ role_path }}/files/keyfile1"
+  ignore_errors: yes
+  become: yes
+  register: create
+- assert:
+    that:
+      - create_check is failed
+      - create is failed
+      - "'is not a device' in create_check.msg"
+      - "'is not a device' in create.msg"