From 2ac54d7c3e309ef44cdaa5e7490697fffda81e8f Mon Sep 17 00:00:00 2001
From: Eric Lippmann <eric.lippmann@netways.de>
Date: Mon, 11 Apr 2016 14:01:36 +0200
Subject: [PATCH] lib: Add ExternalBackend::getRemoteUser()

If the user is authenticated via the web server, this method should be used to retrieve the user because
it supports both reading the user from the environment or from the $_SERVER variable as fallback.

refs #11391
---
 .../Authentication/User/ExternalBackend.php   | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/library/Icinga/Authentication/User/ExternalBackend.php b/library/Icinga/Authentication/User/ExternalBackend.php
index e2cb44716..616f2371e 100644
--- a/library/Icinga/Authentication/User/ExternalBackend.php
+++ b/library/Icinga/Authentication/User/ExternalBackend.php
@@ -52,6 +52,25 @@ class ExternalBackend implements UserBackendInterface
         return $this;
     }
 
+    /**
+     * Get the remote user from environment or $_SERVER, if any
+     *
+     * @param   string  $variable   The name variable where to read the user from
+     *
+     * @return  string|null
+     */
+    public static function getRemoteUser($variable = 'REMOTE_USER')
+    {
+        $username = getenv($variable);
+        if ($username !== false) {
+            return $username;
+        }
+        if (array_key_exists($variable, $_SERVER)) {
+            return $_SERVER[$variable];
+        }
+        return null;
+    }
+
 
     /**
      * {@inheritdoc}