API Security

- added APIAccess class to define access levels of API Endpoints (permissions)
- use "mailpoet_token" for all nonce (just as before)
- merged setupPublic/setupAdmin methods in API in order to avoid duplication
- check permission if access level is not all
- fixed ABSPATH check in some classes

lib/API/API.php

@@ -13,26 +13,25 @@ class API {
   private $_data = array();
 
   function init() {
-    // Admin API (Ajax only)
+     // Admin Security token
+    add_action(
+      'admin_head',
+      array($this, 'setToken')
+    );
+
+    // ajax (logged in users)
     add_action(
       'wp_ajax_mailpoet',
-      array($this, 'setupAdmin')
+      array($this, 'setupAjax')
     );
-
+    // ajax (logged out users)
-    // Public API (Ajax)
     add_action(
       'wp_ajax_nopriv_mailpoet',
-      array($this, 'setupPublic')
+      array($this, 'setupAjax')
     );
   }
 
-  function setupAdmin() {
+  function setupAjax() {
-    $this->getRequestData();
-    $this->checkPermissions();
-    $this->processRoute();
-  }
-
-  function setupPublic() {
     $this->getRequestData();
     $this->checkToken();
     $this->processRoute();
@@ -88,6 +87,18 @@ class API {
   function processRoute() {
     try {
       $endpoint = new $this->_endpoint_class();
+
+      // check the accessibility of the requested endpoint's action
+      // by default, an endpoint's action is considered "private"
+      $permissions = $endpoint->permissions;
+      if(
+        array_key_exists($this->_method, $permissions) === false
+        ||
+        $permissions[$this->_method] !== Access::ALL
+      ) {
+        $this->checkPermissions();
+      }
+
       $response = $endpoint->{$this->_method}($this->_data);
       $response->send();
     } catch(\Exception $e) {
@@ -117,9 +128,7 @@ class API {
   }
 
   function checkToken() {
-    $action = $this->_endpoint.'_'.$this->_method;
+    $is_valid_token = wp_verify_nonce($this->_token, 'mailpoet_token');
-
-    $is_valid_token = wp_verify_nonce($this->_token, $action);
 
     if($is_valid_token === false) {
       $error_response = new ErrorResponse(
@@ -132,4 +141,13 @@ class API {
       $error_response->send();
     }
   }
+
+  function setToken() {
+    $global = '<script type="text/javascript">';
+    $global .= 'var mailpoet_token = "';
+    $global .=  Security::generateToken();
+    $global .= '";';
+    $global .= '</script>';
+    echo $global;
+  }
 }

lib/API/Access.php

@@ -0,0 +1,12 @@
+<?php
+namespace MailPoet\API;
+
+if(!defined('ABSPATH')) exit;
+
+final class Access {
+  const ALL = 'all';
+
+  private function __construct() {
+
+  }
+}

lib/API/Endpoint.php

@@ -5,6 +5,8 @@ if(!defined('ABSPATH')) exit;
 
 abstract class Endpoint {
 
+  public $permissions = array();
+
   function successResponse(
     $data = array(), $meta = array(), $status = Response::STATUS_OK
   ) {

lib/API/Endpoints/Subscribers.php

@@ -2,6 +2,7 @@
 namespace MailPoet\API\Endpoints;
 use \MailPoet\API\Endpoint as APIEndpoint;
 use \MailPoet\API\Error as APIError;
+use \MailPoet\API\Access as APIAccess;
 
 use MailPoet\Listing;
 use MailPoet\Models\Subscriber;
@@ -15,6 +16,11 @@ use MailPoet\Models\StatisticsForms;
 if(!defined('ABSPATH')) exit;
 
 class Subscribers extends APIEndpoint {
+
+  public $permissions = array(
+    'subscribe' => APIAccess::ALL
+  );
+
   function get($data = array()) {
     $id = (isset($data['id']) ? (int)$data['id'] : false);
     $subscriber = Subscriber::findOne($id);

lib/Cron/Daemon.php

@@ -6,6 +6,8 @@ use MailPoet\Cron\Workers\SendingQueue\SendingQueue as SendingQueueWorker;
 if(!defined('ABSPATH')) exit;
 require_once(ABSPATH . 'wp-includes/pluggable.php');
 
+require_once(ABSPATH . 'wp-includes/pluggable.php');
+
 class Daemon {
   public $daemon;
   public $request_data;

lib/Cron/Workers/Scheduler.php

@@ -13,6 +13,8 @@ use MailPoet\Newsletter\Scheduler\Scheduler as NewsletterScheduler;
 if(!defined('ABSPATH')) exit;
 require_once(ABSPATH . 'wp-includes/pluggable.php');
 
+require_once(ABSPATH . 'wp-includes/pluggable.php');
+
 class Scheduler {
   public $timer;
   const UNCONFIRMED_SUBSCRIBER_RESCHEDULE_TIMEOUT = 5;

lib/Form/Widget.php

@@ -161,7 +161,7 @@ class Widget extends \WP_Widget {
         );
 
         // generate security token
-        $data['token'] = Security::generateToken('subscribers_subscribe');
+        $data['token'] = Security::generateToken();
 
         // render form
         $renderer = new Renderer();

lib/Mailer/Mailer.php

@@ -5,6 +5,8 @@ use MailPoet\Models\Setting;
 if(!defined('ABSPATH')) exit;
 require_once(ABSPATH . 'wp-includes/pluggable.php');
 
+require_once(ABSPATH . 'wp-includes/pluggable.php');
+
 class Mailer {
   public $mailer_config;
   public $sender;