From 3a4f0a34f5eb9cf1936d7499c9969ae76a06037d Mon Sep 17 00:00:00 2001
From: tjhunt <tjhunt>
Date: Tue, 23 Sep 2008 05:18:42 +0000
Subject: [PATCH] MDL-13894 Impoved fix with less duplicated code, no notices
 displayed before you get to the 'New settings' screen, and named constants
 instead of magic numbers.

---
 admin/settings/server.php |  6 ++++-
 lib/moodlelib.php         | 52 ++++++++++++++-------------------------
 2 files changed, 24 insertions(+), 34 deletions(-)

diff --git a/admin/settings/server.php b/admin/settings/server.php
index 57e682d469..296eb87558 100644
--- a/admin/settings/server.php
+++ b/admin/settings/server.php
@@ -140,7 +140,11 @@ $temp = new admin_settingpage('http', get_string('http', 'admin'));
 $temp->add(new admin_setting_configtext('framename', get_string('framename', 'admin'), get_string('configframename', 'admin'), '_top', PARAM_ALPHAEXT));
 $temp->add(new admin_setting_configcheckbox('slasharguments', get_string('slasharguments', 'admin'), get_string('configslasharguments', 'admin'), 1));
 $temp->add(new admin_setting_heading('reverseproxy', get_string('reverseproxy', 'admin'), '', ''));
-$options = array(0=>'HTTP_CLIENT_IP, HTTP_X_FORWARDED_FOR, REMOTE_ADDR', 1=>'HTTP_X_FORWARDED_FOR, REMOTE_ADDR', 2=>'HTTP_CLIENT, REMOTE_ADDR', 3=>'REMOTE_ADDR');
+$options = array(
+    0 => 'HTTP_CLIENT_IP, HTTP_X_FORWARDED_FOR, REMOTE_ADDR',
+    GETREMOTEADDR_SKIP_HTTP_CLIENT_IP => 'HTTP_X_FORWARDED_FOR, REMOTE_ADDR',
+    GETREMOTEADDR_SKIP_HTTP_X_FORWARDED_FOR => 'HTTP_CLIENT, REMOTE_ADDR',
+    GETREMOTEADDR_SKIP_HTTP_X_FORWARDED_FOR|GETREMOTEADDR_SKIP_HTTP_CLIENT_IP => 'REMOTE_ADDR');
 $temp->add(new admin_setting_configselect('getremoteaddrconf', get_string('getremoteaddrconf', 'admin'), get_string('configgetremoteaddrconf', 'admin'), 0, $options));
 $temp->add(new admin_setting_heading('webproxy', get_string('webproxy', 'admin'), get_string('webproxyinfo', 'admin')));
 $temp->add(new admin_setting_configtext('proxyhost', get_string('proxyhost', 'admin'), get_string('configproxyhost', 'admin'), '', PARAM_HOST));
diff --git a/lib/moodlelib.php b/lib/moodlelib.php
index c9c5ee8321..3e4fe3e84b 100644
--- a/lib/moodlelib.php
+++ b/lib/moodlelib.php
@@ -7377,43 +7377,29 @@ function remoteip_in_list($list){
  *
  * @return string The remote IP address
  */
+define('GETREMOTEADDR_SKIP_HTTP_CLIENT_IP', '1');
+define('GETREMOTEADDR_SKIP_HTTP_X_FORWARDED_FOR', '2');
 function getremoteaddr() {
     global $CFG;
 
-    switch ($CFG->getremoteaddrconf) {
-        case 3:
-            if (!empty($_SERVER['REMOTE_ADDR'])) {
-                return cleanremoteaddr($_SERVER['REMOTE_ADDR']);
-            }
-            break;
-        case 2:
-            if (!empty($_SERVER['HTTP_CLIENT_IP'])) {
-                return cleanremoteaddr($_SERVER['HTTP_CLIENT_IP']);
-            }
-            if (!empty($_SERVER['REMOTE_ADDR'])) {
-                return cleanremoteaddr($_SERVER['REMOTE_ADDR']);
-            }
-            break;
-        case 1:
-            if (!empty($_SERVER['HTTP_X_FORWARDED_FOR'])) {
-                return cleanremoteaddr($_SERVER['HTTP_X_FORWARDED_FOR']);
-            }
-            if (!empty($_SERVER['REMOTE_ADDR'])) {
-                return cleanremoteaddr($_SERVER['REMOTE_ADDR']);
-            }
-            break;
-        case 0:
-        default:
-            if (!empty($_SERVER['HTTP_CLIENT_IP'])) {
-                return cleanremoteaddr($_SERVER['HTTP_CLIENT_IP']);
-            }
-            if (!empty($_SERVER['HTTP_X_FORWARDED_FOR'])) {
-                return cleanremoteaddr($_SERVER['HTTP_X_FORWARDED_FOR']);
-            }
-            if (!empty($_SERVER['REMOTE_ADDR'])) {
-                return cleanremoteaddr($_SERVER['REMOTE_ADDR']);
-            }
+    if (empty($CFG->getremoteaddrconf)) {
+        // This will happen, for example, before just after the upgrade, as the
+        // user is redirected to the admin screen.
+        $variablestoskip = 0;
+    } else {
+        $variablestoskip = $CFG->getremoteaddrconf;
+    }
+    if (!($variablestoskip & GETREMOTEADDR_SKIP_HTTP_CLIENT_IP)) {
+        if (!empty($_SERVER['HTTP_CLIENT_IP'])) {
+            return cleanremoteaddr($_SERVER['HTTP_CLIENT_IP']);
+        }
+    }
+    if (!($variablestoskip & GETREMOTEADDR_SKIP_HTTP_X_FORWARDED_FOR)) {
+        if (!empty($_SERVER['HTTP_X_FORWARDED_FOR'])) {
+            return cleanremoteaddr($_SERVER['HTTP_X_FORWARDED_FOR']);
+        }
     }
+    return cleanremoteaddr($_SERVER['REMOTE_ADDR']);
 }
 
 /**
-- 
2.39.5