MDL-61351 auth_shibboleth: move new functions to separate class

This reduces the amount of code to an already confusing logout.php
file and prevents conflicts if someone else happens to be using
the same function name in a file.

auth/shibboleth/classes/helper.php

+<?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/>.
+
+/**
+ * Contains a helper class for the Shibboleth authentication plugin.
+ *
+ * @package    auth_shibboleth
+ * @copyright  2018 Mark Nelson <markn@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+namespace auth_shibboleth;
+
+defined('MOODLE_INTERNAL') || die();
+
+/**
+ * The helper class for the Shibboleth authentication plugin.
+ *
+ * @package    auth_shibboleth
+ * @copyright  2018 Mark Nelson <markn@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class helper {
+
+    /**
+     * Delete session of user using file sessions.
+     *
+     * @param string $spsessionid SP-provided Shibboleth Session ID
+     * @return \SoapFault or void if everything was fine
+     */
+    public static function logout_file_session($spsessionid) {
+        global $CFG;
+
+        if (!empty($CFG->session_file_save_path)) {
+            $dir = $CFG->session_file_save_path;
+        } else {
+            $dir = $CFG->dataroot . '/sessions';
+        }
+
+        if (is_dir($dir)) {
+            if ($dh = opendir($dir)) {
+                // Read all session files.
+                while (($file = readdir($dh)) !== false) {
+                    // Check if it is a file.
+                    if (is_file($dir.'/'.$file)) {
+                        // Read session file data.
+                        $data = file($dir.'/'.$file);
+                        if (isset($data[0])) {
+                            $usersession = self::unserializesession($data[0]);
+                            // Check if we have found session that shall be deleted.
+                            if (isset($usersession['SESSION']) && isset($usersession['SESSION']->shibboleth_session_id)) {
+                                // If there is a match, delete file.
+                                if ($usersession['SESSION']->shibboleth_session_id == $spsessionid) {
+                                    // Delete session file.
+                                    if (!unlink($dir.'/'.$file)) {
+                                        return new SoapFault('LogoutError', 'Could not delete Moodle session file.');
+                                    }
+                                }
+                            }
+                        }
+                    }
+                }
+                closedir($dh);
+            }
+        }
+    }
+
+    /**
+     * Delete session of user using DB sessions.
+     *
+     * @param string $spsessionid SP-provided Shibboleth Session ID
+     */
+    public static function logout_db_session($spsessionid) {
+        global $CFG, $DB;
+
+        $sessions = $DB->get_records_sql(
+            'SELECT userid, sessdata FROM {sessions} WHERE timemodified > ?',
+            array(time() - $CFG->sessiontimeout)
+        );
+
+        foreach ($sessions as $session) {
+            // Get user session from DB.
+            if (session_decode(base64_decode($session->sessdata))) {
+                if (isset($_SESSION['SESSION']) && isset($_SESSION['SESSION']->shibboleth_session_id)) {
+                    // If there is a match, kill the session.
+                    if ($_SESSION['SESSION']->shibboleth_session_id == trim($spsessionid)) {
+                        // Delete this user's sessions.
+                        \core\session\manager::kill_user_sessions($session->userid);
+                    }
+                }
+            }
+        }
+    }
+
+    /**
+     * Unserialize a session string.
+     *
+     * @param string $serializedstring
+     * @return array
+     */
+    private static function unserializesession($serializedstring) {
+        $variables = array();
+        $a = preg_split("/(\w+)\|/", $serializedstring, -1, PREG_SPLIT_NO_EMPTY | PREG_SPLIT_DELIM_CAPTURE);
+        $counta = count($a);
+        for ($i = 0; $i < $counta; $i = $i + 2) {
+            $variables[$a[$i]] = unserialize($a[$i + 1]);
+        }
+        return $variables;
+    }
+}

auth/shibboleth/logout.php

@@ -135,94 +135,19 @@ function LogoutNotification($spsessionid) {
     if (!empty($CFG->session_handler_class)) {
         $sessionclass = $CFG->session_handler_class;
         if (preg_match('/database/i', $sessionclass) === 1) {
-            return logoutdbsession($spsessionid);
+            return \auth_shibboleth\helper::logout_db_session($spsessionid);
         } else if (preg_match('/file/i', $sessionclass) === 1) {
-            return logoutfilesession($spsessionid);
+            return \auth_shibboleth\helper::logout_file_session($spsessionid);
         } else {
             throw new moodle_exception("Shibboleth logout not implemented for '$sessionclass'");
         }
     } else {
         // Session handler class is not specified, check dbsessions instead.
         if (!empty($CFG->dbsessions)) {
-            return logoutdbsession($spsessionid);
+            return \auth_shibboleth\helper::logout_db_session($spsessionid);
         }
         // Assume file sessions if dbsessions isn't used.
-        return logoutfilesession($spsessionid);
+        return \auth_shibboleth\helper::logout_file_session($spsessionid);
     }
     // If no SoapFault was thrown, the function will return OK as the SP assumes.
 }
-
-// Delete session of user using $spsessionid.
-function logoutfilesession($spsessionid) {
-    global $CFG;
-
-    if (!empty($CFG->session_file_save_path)) {
-        $dir = $CFG->session_file_save_path;
-    } else {
-        $dir = $CFG->dataroot . '/sessions';
-    }
-
-    if (is_dir($dir)) {
-        if ($dh = opendir($dir)) {
-            // Read all session files.
-            while (($file = readdir($dh)) !== false) {
-                // Check if it is a file.
-                if (is_file($dir.'/'.$file)) {
-
-                    // Read session file data.
-                    $data = file($dir.'/'.$file);
-                    if (isset($data[0])) {
-                        $usersession = unserializesession($data[0]);
-
-                        // Check if we have found session that shall be deleted.
-                        if (isset($usersession['SESSION']) && isset($usersession['SESSION']->shibboleth_session_id)) {
-
-                            // If there is a match, delete file.
-                            if ($usersession['SESSION']->shibboleth_session_id == $spsessionid) {
-                                // Delete session file.
-                                if (!unlink($dir.'/'.$file)) {
-                                    return new SoapFault('LogoutError', 'Could not delete Moodle session file.');
-                                }
-                            }
-                        }
-                    }
-                }
-            }
-            closedir($dh);
-        }
-    }
-}
-
-function logoutdbsession($spsessionid) {
-    global $CFG, $DB;
-    $sessions = $DB->get_records_sql(
-        'SELECT userid, sessdata FROM {sessions} WHERE timemodified > ?',
-        array(time() - $CFG->sessiontimeout)
-    );
-    foreach ($sessions as $session) {
-        // Get user session from DB.
-        if (session_decode(base64_decode($session->sessdata))) {
-            if (isset($_SESSION['SESSION']) && isset($_SESSION['SESSION']->shibboleth_session_id)) {
-                // If there is a match, kill the session.
-                if ($_SESSION['SESSION']->shibboleth_session_id == trim($spsessionid)) {
-                    // Delete this user's sessions.
-                    \core\session\manager::kill_user_sessions($session->userid);
-                }
-            }
-        }
-    }
-}
-
-/*****************************************************************************/
-
-// Same function as in adodb, but cannot be used for file session for some reason...
-function unserializesession($serialized_string) {
-    $variables = array();
-    $a = preg_split("/(\w+)\|/", $serialized_string, -1, PREG_SPLIT_NO_EMPTY | PREG_SPLIT_DELIM_CAPTURE);
-    $counta = count($a);
-    for ($i = 0; $i < $counta; $i = $i+2) {
-            $variables[$a[$i]] = unserialize($a[$i+1]);
-    }
-    return $variables;
-}
-

auth/shibboleth/upgrade.txt

 This files describes API changes in /auth/shibboleth/*,
 information provided here is intended especially for developers.
 
+=== 3.5.2 ===
+
+* Moved the public function unserializesession in auth/shibboleth/logout.php to auth/shibboleth/classes/helper.php and
+  made it private. This function should not have been used outside of this file.
+
 === 3.3 ===
 
 * The config.html file was migrated to use the admin settings API.