Security update for Core, with self-updated composer

[yaffs-website] / web / core / modules / media / src / Access / MediaRevisionAccessCheck.php

diff --git a/web/core/modules/media/src/Access/MediaRevisionAccessCheck.php b/web/core/modules/media/src/Access/MediaRevisionAccessCheck.php
new file mode 100644 (file)
index 0000000..fb3d560
--- /dev/null
+++ b/web/core/modules/media/src/Access/MediaRevisionAccessCheck.php
@@ -0,0 +1,151 @@
+<?php
+
+namespace Drupal\media\Access;
+
+use Drupal\Core\Access\AccessResult;
+use Drupal\Core\Entity\EntityTypeManagerInterface;
+use Drupal\Core\Routing\Access\AccessInterface;
+use Drupal\Core\Session\AccountInterface;
+use Drupal\media\MediaInterface;
+use Symfony\Component\Routing\Route;
+
+/**
+ * Provides an access checker for media item revisions.
+ *
+ * @ingroup media_access
+ */
+class MediaRevisionAccessCheck implements AccessInterface {
+
+  /**
+   * The media storage.
+   *
+   * @var \Drupal\Core\Entity\ContentEntityStorageInterface
+   */
+  protected $mediaStorage;
+
+  /**
+   * The media access control handler.
+   *
+   * @var \Drupal\Core\Entity\EntityAccessControlHandlerInterface
+   */
+  protected $mediaAccess;
+
+  /**
+   * A static cache of access checks.
+   *
+   * @var array
+   */
+  protected $access = [];
+
+  /**
+   * Constructs a new MediaRevisionAccessCheck.
+   *
+   * @param \Drupal\Core\Entity\EntityTypeManagerInterface $entity_type_manager
+   *   The entity type manager.
+   */
+  public function __construct(EntityTypeManagerInterface $entity_type_manager) {
+    $this->mediaStorage = $entity_type_manager->getStorage('media');
+    $this->mediaAccess = $entity_type_manager->getAccessControlHandler('media');
+  }
+
+  /**
+   * Checks routing access for the media item revision.
+   *
+   * @param \Symfony\Component\Routing\Route $route
+   *   The route to check against.
+   * @param \Drupal\Core\Session\AccountInterface $account
+   *   The currently logged in account.
+   * @param int $media_revision
+   *   (optional) The media item revision ID. If not specified, but $media is,
+   *   access is checked for that object's revision.
+   * @param \Drupal\media\MediaInterface $media
+   *   (optional) A media item. Used for checking access to a media items
+   *   default revision when $media_revision is unspecified. Ignored when
+   *   $media_revision is specified. If neither $media_revision nor $media are
+   *   specified, then access is denied.
+   *
+   * @return \Drupal\Core\Access\AccessResultInterface
+   *   The access result.
+   */
+  public function access(Route $route, AccountInterface $account, $media_revision = NULL, MediaInterface $media = NULL) {
+    if ($media_revision) {
+      $media = $this->mediaStorage->loadRevision($media_revision);
+    }
+    $operation = $route->getRequirement('_access_media_revision');
+    return AccessResult::allowedIf($media && $this->checkAccess($media, $account, $operation))->cachePerPermissions()->addCacheableDependency($media);
+  }
+
+  /**
+   * Checks media item revision access.
+   *
+   * @param \Drupal\media\MediaInterface $media
+   *   The media item to check.
+   * @param \Drupal\Core\Session\AccountInterface $account
+   *   A user object representing the user for whom the operation is to be
+   *   performed.
+   * @param string $op
+   *   (optional) The specific operation being checked. Defaults to 'view'.
+   *
+   * @return bool
+   *   TRUE if the operation may be performed, FALSE otherwise.
+   */
+  public function checkAccess(MediaInterface $media, AccountInterface $account, $op = 'view') {
+    if (!$media || $op !== 'view') {
+      // If there was no media to check against, or the $op was not one of the
+      // supported ones, we return access denied.
+      return FALSE;
+    }
+
+    // Statically cache access by revision ID, language code, user account ID,
+    // and operation.
+    $langcode = $media->language()->getId();
+    $cid = $media->getRevisionId() . ':' . $langcode . ':' . $account->id() . ':' . $op;
+
+    if (!isset($this->access[$cid])) {
+      // Perform basic permission checks first.
+      if (!$account->hasPermission('view all media revisions') && !$account->hasPermission('administer media')) {
+        $this->access[$cid] = FALSE;
+        return FALSE;
+      }
+
+      // There should be at least two revisions. If the revision ID of the
+      // given media item and the revision ID of the default revision differ,
+      // then we already have two different revisions so there is no need for a
+      // separate database check.
+      if ($media->isDefaultRevision() && ($this->countDefaultLanguageRevisions($media) == 1)) {
+        $this->access[$cid] = FALSE;
+      }
+      elseif ($account->hasPermission('administer media')) {
+        $this->access[$cid] = TRUE;
+      }
+      else {
+        // First check the access to the default revision and finally, if the
+        // media passed in is not the default revision then access to that, too.
+        $this->access[$cid] = $this->mediaAccess->access($this->mediaStorage->load($media->id()), $op, $account) && ($media->isDefaultRevision() || $this->mediaAccess->access($media, $op, $account));
+      }
+    }
+
+    return $this->access[$cid];
+  }
+
+  /**
+   * Counts the number of revisions in the default language.
+   *
+   * @param \Drupal\media\MediaInterface $media
+   *   The media item for which to to count the revisions.
+   *
+   * @return int
+   *   The number of revisions in the default language.
+   */
+  protected function countDefaultLanguageRevisions(MediaInterface $media) {
+    $entity_type = $media->getEntityType();
+    $count = $this->mediaStorage->getQuery()
+      ->allRevisions()
+      ->condition($entity_type->getKey('id'), $media->id())
+      ->condition($entity_type->getKey('default_langcode'), 1)
+      ->count()
+      ->execute();
+    return $count;
+  }
+
+}