diff --git a/core/modules/basic_auth/basic_auth.services.yml b/core/modules/basic_auth/basic_auth.services.yml
index 13a6cb1..4c7a449 100644
--- a/core/modules/basic_auth/basic_auth.services.yml
+++ b/core/modules/basic_auth/basic_auth.services.yml
@@ -1,6 +1,6 @@
 services:
   authentication.basic_auth:
     class: Drupal\basic_auth\Authentication\Provider\BasicAuth
-    arguments: ['@config.factory']
+    arguments: ['@config.factory', '@user.auth']
     tags:
       - { name: authentication_provider, priority: 100 }
diff --git a/core/modules/basic_auth/lib/Drupal/basic_auth/Authentication/Provider/BasicAuth.php b/core/modules/basic_auth/lib/Drupal/basic_auth/Authentication/Provider/BasicAuth.php
index 79fe59f..f8f221a 100644
--- a/core/modules/basic_auth/lib/Drupal/basic_auth/Authentication/Provider/BasicAuth.php
+++ b/core/modules/basic_auth/lib/Drupal/basic_auth/Authentication/Provider/BasicAuth.php
@@ -11,6 +11,7 @@
 use Drupal\Core\Authentication\AuthenticationProviderInterface;
 use Drupal\Core\Config\Config;
 use Drupal\Core\Config\ConfigFactoryInterface;
+use Drupal\user\UserAuthInterface;
 use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpKernel\Event\GetResponseForExceptionEvent;
 use Symfony\Component\HttpKernel\Exception\UnauthorizedHttpException;
@@ -29,13 +30,21 @@ class BasicAuth implements AuthenticationProviderInterface {
   protected $configFactory;
 
   /**
+   * The user auth service.
+   *
+   * @var \Drupal\user\UserAuthInterface
+   */
+  protected $userAuth;
+
+  /**
    * Constructs a HTTP basic authentication provider object.
    *
    * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
    *   The config factory.
    */
-  public function __construct(ConfigFactoryInterface $config_factory) {
+  public function __construct(ConfigFactoryInterface $config_factory, UserAuthInterface $user_auth) {
     $this->configFactory = $config_factory;
+    $this->userAuth = $user_auth;
   }
 
   /**
@@ -53,7 +62,7 @@ public function applies(Request $request) {
   public function authenticate(Request $request) {
     $username = $request->headers->get('PHP_AUTH_USER');
     $password = $request->headers->get('PHP_AUTH_PW');
-    $uid = user_authenticate($username, $password);
+    $uid = $this->userAuth->authenticate($username, $password);
     if ($uid) {
       return user_load($uid);
     }
diff --git a/core/modules/user/lib/Drupal/user/UserAuth.php b/core/modules/user/lib/Drupal/user/UserAuth.php
index 01ecf46..3ce2683 100644
--- a/core/modules/user/lib/Drupal/user/UserAuth.php
+++ b/core/modules/user/lib/Drupal/user/UserAuth.php
@@ -28,17 +28,19 @@ class UserAuth implements UserAuthInterface {
    *
    * @var \Drupal\Core\Password\PasswordInterface
    */
-  protected $password;
+  protected $passwordChecker;
 
   /**
    * Constructs a UserAuth object.
    *
-   * @param EntityStorageControllerInterface $storage
-   * @param PasswordInterface $password
+   * @param \Drupal\Core\Entity\EntityStorageControllerInterface $storage
+   *   The user storage.
+   * @param \Drupal\Core\Password\PasswordInterface $password_checker
+   *   The password service.
    */
-  public function __construct(EntityManagerInterface $entity_manager, PasswordInterface $password) {
+  public function __construct(EntityManagerInterface $entity_manager, PasswordInterface $password_checker) {
     $this->storage = $entity_manager->getStorageController('user');
-    $this->password = $password;
+    $this->passwordChecker = $password_checker;
   }
 
   /**
@@ -51,12 +53,12 @@ public function authenticate($username, $password) {
       $account_search = $this->storage->loadByProperties(array('name' => $username));
 
       if ($account = reset($account_search)) {
-        if ($this->password->check($password, $account)) {
+        if ($this->passwordChecker->check($password, $account)) {
           // Successful authentication.
           $uid = $account->id();
 
           // Update user to new password scheme if needed.
-          if ($this->password->userNeedsNewHash($account)) {
+          if ($this->passwordChecker->userNeedsNewHash($account)) {
             $account->setPassword($password);
             $account->save();
           }
diff --git a/core/modules/user/user.module b/core/modules/user/user.module
index 9b2194b..9d7b032 100644
--- a/core/modules/user/user.module
+++ b/core/modules/user/user.module
@@ -900,26 +900,12 @@ function user_page_title(UserInterface $account = NULL) {
  *   A plain-text password, such as trimmed text from form values.
  * @return
  *   The user's uid on success, or FALSE on failure to authenticate.
+ *
+ * @deprecated in Drupal 8.x-dev, will be removed before Drupal 8.0.
+ *   Use \Drupal\user\UserAuth::authenticate() instead.
  */
 function user_authenticate($name, $password) {
-  $uid = FALSE;
-  if (!empty($name) && !empty($password)) {
-    $account = user_load_by_name($name);
-    if ($account) {
-      $password_hasher = \Drupal::service('password');
-      if ($password_hasher->check($password, $account)) {
-        // Successful authentication.
-        $uid = $account->id();
-
-        // Update user to new password scheme if needed.
-        if ($password_hasher->userNeedsNewHash($account)) {
-          $account->setPassword($password);
-          $account->save();
-        }
-      }
-    }
-  }
-  return $uid;
+  return \Drupal::service('user_auth')->authenticate($name, $password);
 }
 
 /**