support for CAS fixedServiceURL

app/config/auth.conf.dist.php

@@ -120,4 +120,6 @@ $cas = [
     // 'verbose' => false,
     // 'debug' => '/var/log/cas_debug.log',
     'noCasServerValidation' => true, // set to false in production
+    // 'fixedServiceURL' => false, // false by default, set to either true or to the service URL string if needed
+    // sites might also need proxy_settings in configuration.php
 ];

main/auth/cas/cas_var.inc.php

@@ -47,10 +47,8 @@ if (api_is_cas_activated()) {
             phpCAS::setNoCasServerValidation();
         }
 
-        global $_configuration;
-        if (is_array($_configuration)
-            && array_key_exists('proxy_settings', $_configuration)) {
-            $proxySettings = $_configuration['proxy_settings'];
+        $proxySettings = api_get_configuration_value('proxy_settings');
+        if (false !== $proxySettings) {
             if (is_array($proxySettings) && array_key_exists('https', $proxySettings)) {
                 $https = $proxySettings['https'];
                 if (is_string($https) && !empty($https)) {
@@ -58,5 +56,14 @@ if (api_is_cas_activated()) {
                 }
             }
         }
+
+        if (is_array($cas) && array_key_exists('fixedServiceURL', $cas)) {
+            $fixedServiceURL = $cas['fixedServiceURL'];
+            if (is_string($fixedServiceURL)) {
+                phpCAS::setFixedServiceURL($fixedServiceURL);
+            } else if (is_bool($fixedServiceURL) && $fixedServiceURL) {
+                phpCAS::setFixedServiceURL(api_get_configuration_value('root_web'));
+            }
+        }
     }
 }