Implement hook for TLS root CA certificate collections locking

refs #3016

application/controllers/TlsrootcacollectionController.php

@@ -4,6 +4,7 @@
 namespace Icinga\Controllers;
 
 use Exception;
+use Icinga\Application\Hook;
 use Icinga\Application\Icinga;
 use Icinga\File\Storage\LocalFileStorage;
 use Icinga\Forms\Config\Tls\RootCaCollection\AddCaForm;
@@ -106,6 +107,17 @@ class TlsrootcacollectionController extends Controller
 
         $this->view->form = $form = new ConfirmRemovalForm();
         $form->setOnSuccess(function (ConfirmRemovalForm $form) use ($name, $fileName, $rootCaCollections) {
+                foreach (Hook::all('TlsRootCACertificateCollection') as $hook) {
+                    /** @var Hook\TlsRootCACertificateCollectionHook $hook */
+
+                    try {
+                        $hook->beforeRemove($name);
+                    } catch (Exception $e) {
+                        $form->error($e->getMessage());
+                        return false;
+                    }
+                }
+
                 try {
                     $rootCaCollections->delete($fileName);
                 } catch (Exception $e) {

application/forms/Config/Tls/RootCaCollection/EditForm.php

@@ -4,6 +4,7 @@
 namespace Icinga\Forms\Config\Tls\RootCaCollection;
 
 use Exception;
+use Icinga\Application\Hook;
 use Icinga\File\Storage\LocalFileStorage;
 use Icinga\Web\Form;
 
@@ -54,6 +55,29 @@ class EditForm extends Form
         $name = $this->getElement('name')->getValue();
 
         if ($name !== $this->oldName) {
+            /** @var Hook\TlsRootCACertificateCollectionHook[] $succeededCascades */
+            $succeededCascades = array();
+
+            foreach (Hook::all('TlsRootCACertificateCollection') as $hook) {
+                /** @var Hook\TlsRootCACertificateCollectionHook $hook */
+
+                try {
+                    $hook->beforeRename($this->oldName, $name);
+                } catch (Exception $e) {
+                    foreach ($succeededCascades as $succeededCascade) {
+                        try {
+                            $succeededCascade->beforeRename($name, $this->oldName);
+                        } catch (Exception $_) {
+                        }
+                    }
+
+                    $this->error($e->getMessage());
+                    return false;
+                }
+
+                $succeededCascades[] = $hook;
+            }
+
             try {
                 $rootCaCollections = LocalFileStorage::common('tls/rootcacollections');
                 $oldFileName = bin2hex($this->oldName) . '.pem';
@@ -61,6 +85,13 @@ class EditForm extends Form
                 $rootCaCollections->create(bin2hex($name) . '.pem', $rootCaCollections->read($oldFileName));
                 $rootCaCollections->delete($oldFileName);
             } catch (Exception $e) {
+                foreach ($succeededCascades as $succeededCascade) {
+                    try {
+                        $succeededCascade->beforeRename($name, $this->oldName);
+                    } catch (Exception $_) {
+                    }
+                }
+
                 $this->error($e->getMessage());
                 return false;
             }

library/Icinga/Application/Hook/TlsRootCACertificateCollectionHook.php

@@ -0,0 +1,52 @@
+<?php
+/* Icinga Web 2 | (c) 2017 Icinga Development Team | GPLv2+ */
+
+namespace Icinga\Application\Hook;
+
+/**
+ * TLS root CA certificate collection hook base class
+ *
+ * Extend this class if you want to prevent TLS root CA certificate collections used by your module from being removed.
+ */
+abstract class TlsRootCACertificateCollectionHook
+{
+    /**
+     * Constructor
+     */
+    final public function __construct()
+    {
+        $this->init();
+    }
+
+    /**
+     * Overwrite this function if you want to do some initialization stuff
+     *
+     * @return void
+     */
+    protected function init()
+    {
+    }
+
+    /**
+     * Called before the given root CA certificate collection is removed
+     *
+     * If an exception is thrown, the removal fails.
+     *
+     * @param   string      $collectionName
+     *
+     * @throws  \Exception
+     */
+    abstract public function beforeRemove($collectionName);
+
+    /**
+     * Called before a root CA certificate collection is renamed as given
+     *
+     * If an exception is thrown, the renaming fails.
+     *
+     * @param   string      $oldCollectionName
+     * @param   string      $newCollectionName
+     *
+     * @throws  \Exception
+     */
+    abstract public function beforeRename($oldCollectionName, $newCollectionName);
+}