MDL-60432 auth_cas: Using Identity Providers for Authentication CAS

Using Identity Providers for  Authentication CAS , instead of cas_form.html

auth/cas/auth.php

@@ -130,21 +130,10 @@ class auth_plugin_cas extends auth_plugin_ldap {
             }
 
             $authCAS = optional_param('authCAS', '', PARAM_RAW);
-            if ($authCAS == 'NOCAS') {
+            if ($authCAS != 'CAS') {
                 return;
             }
-            // Show authentication form for multi-authentication.
-            // Test pgtIou parameter for proxy mode (https connection in background from CAS server to the php server).
-            if ($authCAS != 'CAS' && !isset($_GET['pgtIou'])) {
-                $PAGE->set_url('/login/index.php');
-                $PAGE->navbar->add($CASform);
-                $PAGE->set_title("$site->fullname: $CASform");
-                $PAGE->set_heading($site->fullname);
-                echo $OUTPUT->header();
-                include($CFG->dirroot.'/auth/cas/cas_form.html');
-                echo $OUTPUT->footer();
-                exit();
-            }
+
         }
 
         // Connection to CAS server
@@ -363,4 +352,25 @@ class auth_plugin_cas extends auth_plugin_ldap {
             phpCAS::logoutWithRedirectService($backurl);
         }
     }
+
+    /**
+     * Return a list of identity providers to display on the login page.
+     *
+     * @param string|moodle_url $wantsurl The requested URL.
+     * @return array List of arrays with keys url, iconurl and name.
+     */
+    public function loginpage_idp_list($wantsurl) {
+        global $CFG;
+        $config = get_config('auth_cas');
+        $params = ["authCAS" => "CAS"];
+        $url = new moodle_url(get_login_url(), $params);
+        $iconurl = moodle_url::make_pluginfile_url(context_system::instance()->id,
+                                                   'auth_cas',
+                                                   'logo',
+                                                   null,
+                                                   '/',
+                                                   $config->auth_logo);
+        $result[] = ['url' => $url, 'iconurl' => $iconurl, 'name' => $config->auth_name];
+        return $result;
+    }
 }

auth/cas/lang/en/auth_cas.php

@@ -24,6 +24,10 @@
 
 $string['accesCAS'] = 'CAS users';
 $string['accesNOCAS'] = 'other users';
+$string['auth_cas_auth_name'] = 'Authentication method name';
+$string['auth_cas_auth_name_description'] = 'Provide a name for the CAS authentication method that is familiar to your users.';
+$string['auth_cas_auth_logo'] = 'Authentication method logo';
+$string['auth_cas_auth_logo_description'] = 'Provide a logo for the CAS authentication method that is familiar to your users.';
 $string['auth_cas_auth_user_create'] = 'Create users externally';
 $string['auth_cas_baseuri'] = 'URI of the server (nothing if no baseUri)<br />For example, if the CAS server responds to host.domaine.fr/CAS/ then<br />cas_baseuri = CAS/';
 $string['auth_cas_baseuri_key'] = 'Base URI';

auth/cas/lib.php

@@ -0,0 +1,75 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Authentication Plugin: CAS Authentication
+ *
+ * Authentication using CAS (Central Authentication Server).
+ *
+ * @package auth_cas
+ * @copyright 1999 onwards Martin Dougiamas  {@link http://moodle.com}
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+
+
+defined('MOODLE_INTERNAL') || die;
+
+/**
+ * Serves the logo file settings.
+ *
+
+ * @param stdClass $course course object
+ * @param stdClass $cm course module object
+ * @param stdClass $context context object
+ * @param string $filearea file area
+ * @param array $args extra arguments
+ * @param bool $forcedownload whether or not force download
+ * @param array $options additional options affecting the file serving
+ * @return bool false if file not found, does not return if found - justsend the file
+ */
+function auth_cas_pluginfile($course, $cm, $context, $filearea, $args, $forcedownload, array $options=array()) {
+    if ($context->contextlevel != CONTEXT_SYSTEM) {
+        return false;
+    }
+
+    if ($filearea !== 'logo' ) {
+        return false;
+    }
+
+    $itemid = 0;
+    // Use the itemid to retrieve any relevant data records and perform any security checks to see if the
+    // user really does have access to the file in question.
+
+    // Extract the filename / filepath from the $args array.
+    $filename = array_pop($args); // The last item in the $args array.
+    if (!$args) {
+        $filepath = '/'; // $args is empty => the path is '/'
+    } else {
+        $filepath = '/'.implode('/', $args).'/'; // $args contains elements of the filepath
+    }
+
+    // Retrieve the file from the Files API.
+    $fs = get_file_storage();
+    $file = $fs->get_file($context->id, 'auth_cas', $filearea, $itemid, $filepath, $filename);
+    if (!$file) {
+        return false; // The file does not exist.
+    }
+
+    // We can now send the file back to the browser - in this case with a cache lifetime of 1 day and no filtering.
+    // From Moodle 2.3, use send_stored_file instead.
+    send_stored_file($file, null, 0, $forcedownload, $options);
+}

auth/cas/settings.php

@@ -45,6 +45,18 @@ if ($ADMIN->fulltree) {
         $settings->add(new admin_setting_heading('auth_cas/casserversettings',
                 new lang_string('auth_cas_server_settings', 'auth_cas'), ''));
 
+        // Authentication method name.
+        $settings->add(new admin_setting_configtext('auth_cas/auth_name',
+                get_string('auth_cas_auth_name', 'auth_cas'),
+                get_string('auth_cas_auth_name_description', 'auth_cas'), '', PARAM_RAW_TRIMMED));
+
+        // Authentication method logo.
+        $opts = array('accepted_types' => array('.png', '.jpg', '.gif', '.webp', '.tiff', '.svg'));
+        $settings->add(new admin_setting_configstoredfile('auth_cas/auth_logo',
+                 get_string('auth_cas_auth_logo', 'auth_cas'),
+                 get_string('auth_cas_auth_logo_description', 'auth_cas'), 'logo', 0, $opts));
+
+
         // Hostname.
         $settings->add(new admin_setting_configtext('auth_cas/hostname',
                 get_string('auth_cas_hostname_key', 'auth_cas'),