diff --git a/src/Model/User.php b/src/Model/User.php
index 01bcce28d9..a7f59b6a3d 100644
--- a/src/Model/User.php
+++ b/src/Model/User.php
@@ -1,22 +1,71 @@
 <?php
+
 /**
  * @file src/Model/User.php
  * @brief This file includes the User class with user related database functions
  */
+
 namespace Friendica\Model;
 
 use Friendica\Core\System;
 use Friendica\Core\Worker;
+use Friendica\Database\DBM;
 use dba;
 
 require_once 'boot.php';
-require_once 'plugin.php';
+require_once 'include/plugin.php';
 
 /**
  * @brief This class handles User related functions
  */
 class User
 {
+	public static function authenticate($user_info, $password)
+	{
+		if (is_object($user_info)) {
+			$user = (array) $user_info;
+		} elseif (is_int($user_info)) {
+			$user = dba::select('user',
+				['uid', 'password'],
+				[
+					'uid' => $user_info,
+					'blocked' => 0,
+					'account_expired' => 0,
+					'account_removed' => 0,
+					'verified' => 1
+				],
+				['limit' => 1]
+			);
+		} elseif (is_string($user_info)) {
+			$user = dba::fetch_first('SELECT `uid`, `password`
+				FROM `user`
+				WHERE (`email` = ? OR `username` = ? OR `nickname` = ?)
+				AND `blocked` = 0
+				AND `account_expired` = 0
+				AND `account_removed` = 0
+				AND `verified` = 1
+				LIMIT 1',
+				$user_info,
+				$user_info,
+				$user_info
+			);
+		} else {
+			$user = $user_info;
+		}
+
+		if (!DBM::isResult($user) || !isset($user['uid']) || !isset($user['password'])) {
+			return false;
+		}
+
+		$password_hashed = hash('whirlpool', $password);
+
+		if ($password_hashed !== $user['password']) {
+			return false;
+		}
+
+		return $user['uid'];
+	}
+
 	/**
 	 * @param object $uid user to remove
 	 * @return void