From a762b3809afbc737cc7a447ed78376cfad152ed4 Mon Sep 17 00:00:00 2001
From: Coleman Watts <coleman@civicrm.org>
Date: Thu, 7 Jan 2016 15:59:42 -0500
Subject: [PATCH] CRM-17795 - Add basic permission checks for api joins

---
 Civi/API/SelectQuery.php | 38 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 38 insertions(+)

diff --git a/Civi/API/SelectQuery.php b/Civi/API/SelectQuery.php
index d9879eeccb..ca054b4db6 100644
--- a/Civi/API/SelectQuery.php
+++ b/Civi/API/SelectQuery.php
@@ -341,6 +341,10 @@ class SelectQuery {
       if (!isset($fkField['FKApiName']) && !isset($fkField['FKClassName'])) {
         return NULL;
       }
+      // Ensure we have permission to access the other api
+      if (!$this->checkPermissionToJoin($fkField['FKApiName'], array_slice($stack, 0, $depth))) {
+        return NULL;
+      }
       if (!isset($fkField['FKApiSpec'])) {
         $fkField['FKApiSpec'] = \_civicrm_api_get_fields($fkField['FKApiName']);
       }
@@ -411,4 +415,38 @@ class SelectQuery {
     return NULL;
   }
 
+  /**
+   * Check permission to join onto another api entity
+   *
+   * @param string $entity
+   * @param array $fieldStack
+   *   The stack of fields leading up to this join
+   * @return bool
+   */
+  private function checkPermissionToJoin($entity, $fieldStack) {
+    if (empty($this->params['check_permissions'])) {
+      return TRUE;
+    }
+    // Build an array of params that relate to the joined entity
+    $params = array(
+      'version' => 3,
+      'return' => array(),
+      'check_permissions' => \CRM_Utils_Array::value('check_permissions', $this->params, FALSE),
+    );
+    $prefix = implode('.', $fieldStack) . '.';
+    $len = strlen($prefix);
+    foreach ($this->options['return'] as $key => $ret) {
+      if (strpos($key, $prefix) === 0) {
+        $params['return'][substr($key, $len)] = $ret;
+      }
+    }
+    foreach ($this->params as $key => $param) {
+      if (strpos($key, $prefix) === 0) {
+        $params[substr($key, $len)] = $param;
+      }
+    }
+
+    return \Civi::service('civi_api_kernel')->runAuthorize($entity, 'get', $params);
+  }
+
 }
-- 
2.25.1