Auth.php

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<?php
/* vim: set expandtab tabstop=4 shiftwidth=4 softtabstop=4 foldmethod=marker: */

include_once './Services/Authentication/classes/class.ilAuthBase.php';

define('AUTH_IDLED',                    -1);
define('AUTH_EXPIRED',                  -2);
define('AUTH_WRONG_LOGIN',              -3);
define('AUTH_METHOD_NOT_SUPPORTED',     -4);
define('AUTH_SECURITY_BREACH',          -5);
define('AUTH_CALLBACK_ABORT',           -6);

define('AUTH_LOG_INFO',     6);
define('AUTH_LOG_DEBUG',    7);

define('AUTH_ADV_IPCHECK', 1);
define('AUTH_ADV_USERAGENT', 2);
define('AUTH_ADV_CHALLENGE', 3);


class Auth extends ilAuthBase {

    // {{{ properties

    var $expire = 0;

    var $expired = false;

    var $idle = 0;

    var $idled = false;

    var $storage = '';

    var $loginFunction = '';

    var $showLogin = true;

    var $allowLogin = true;

    var $status = '';

    var $username = '';

    var $password = '';

    var $checkAuthCallback = '';

    var $loginCallback = '';

    var $loginFailedCallback = '';

    var $logoutCallback = '';

    var $_sessionName = '_authsession';

    var $version = "@version@";

    var $advancedsecurity = false;

    var $_postUsername = 'username';

    var $_postPassword = 'password';

    var $session;

    var $server;

    var $post;

    var $cookie;

    var $authdata;

    var $authChecks = 0;

    var $logger = null;

    var $enableLogging = false;

    var $regenerateSessionId = false;

    // }}}
    // {{{ Auth() [constructor]

    function Auth($storageDriver, $options = '', $loginFunction = '', $showLogin = true)
    {
        $this->applyAuthOptions($options);

        // Start the session suppress error if already started
        if(!session_id()){
            @session_start();
            if(!session_id()) {
                // Throw error
                include_once 'PEAR.php';
                PEAR::throwError('Session could not be started by Auth, '
                        .'possibly headers are already sent, try putting '
                        .'ob_start in the beginning of your script');
            }
        }

        // Make Sure Auth session variable is there
        if(!isset($_SESSION[$this->_sessionName])) {
            $_SESSION[$this->_sessionName] = array();
        }

        // Assign Some globals to internal references, this will replace _importGlobalVariable
        $this->session =& $_SESSION[$this->_sessionName];
        $this->server =& $_SERVER;
        $this->post =& $_POST;
        $this->cookie =& $_COOKIE;

        if ($loginFunction != '' && is_callable($loginFunction)) {
            $this->loginFunction = $loginFunction;
        }

        if (is_bool($showLogin)) {
            $this->showLogin = $showLogin;
        }

        if (is_object($storageDriver)) {
            $this->storage =& $storageDriver;
            // Pass a reference to auth to the container, ugly but works
            // this is used by the DB container to use method setAuthData not staticaly.
            $this->storage->_auth_obj =& $this;
        } else {
            // $this->storage = $this->_factory($storageDriver, $options);
            //
            $this->storage_driver = $storageDriver;
            $this->storage_options =& $options;
        }
    }

    // }}}
    // {{{ applyAuthOptions()

    function &applyAuthOptions(&$options)
    {
        if(is_array($options)){
            if (!empty($options['sessionName'])) {
                $this->_sessionName = $options['sessionName'];
                unset($options['sessionName']);
            }
            if (isset($options['allowLogin'])) {
                $this->allowLogin = $options['allowLogin'];
                unset($options['allowLogin']);
            }
            if (!empty($options['postUsername'])) {
                $this->_postUsername = $options['postUsername'];
                unset($options['postUsername']);
            }
            if (!empty($options['postPassword'])) {
                $this->_postPassword = $options['postPassword'];
                unset($options['postPassword']);
            }
            if (isset($options['advancedsecurity'])) {
                $this->advancedsecurity = $options['advancedsecurity'];
                unset($options['advancedsecurity']);
            }
            if (isset($options['enableLogging'])) {
                $this->enableLogging = $options['enableLogging'];
                unset($options['enableLogging']);
            }
            if (isset($options['regenerateSessionId']) && is_bool($options['regenerateSessionId'])) {
                $this->regenerateSessionId = $options['regenerateSessionId'];
            }
        }
        return($options);
    }

    // }}}
    // {{{ _loadStorage()

    function _loadStorage()
    {
        if(!is_object($this->storage)) {
            $this->storage =& $this->_factory($this->storage_driver,
                    $this->storage_options);
            $this->storage->_auth_obj =& $this;
            $this->log('Loaded storage container ('.$this->storage_driver.')', AUTH_LOG_DEBUG);
            return(true);
        }
        return(false);
    }

    // }}}
    // {{{ _factory()

    function &_factory($driver, $options = '')
    {
        $storage_class = 'Auth_Container_' . $driver;
        include_once 'Auth/Container/' . $driver . '.php';
        $obj =& new $storage_class($options);
        return $obj;
    }

    // }}}
    // {{{ assignData()

    function assignData()
    {
        $this->log('Auth::assignData() called.', AUTH_LOG_DEBUG);

        if (   isset($this->post[$this->_postUsername])
            && $this->post[$this->_postUsername] != '') {
            $this->username = (get_magic_quotes_gpc() == 1
                    ? stripslashes($this->post[$this->_postUsername])
                    : $this->post[$this->_postUsername]);
        }
        if (   isset($this->post[$this->_postPassword])
            && $this->post[$this->_postPassword] != '') {
            $this->password = (get_magic_quotes_gpc() == 1
                    ? stripslashes($this->post[$this->_postPassword])
                    : $this->post[$this->_postPassword] );
        }
    }

    // }}}
    // {{{ start()

    function start()
    {
        $this->log('Auth::start() called.', AUTH_LOG_DEBUG);

        // #10729 - Regenerate session id here if we are generating it on every
        //          page load.
        if ($this->regenerateSessionId) {
            session_regenerate_id(true);
        }
        
        $this->assignData();
        if (!$this->checkAuth() && $this->allowLogin) {
            $this->login();
        }
    }

    // }}}
    // {{{ login()

    function login()
    {
        $this->log('Auth::login() called.', AUTH_LOG_DEBUG);

        $login_ok = false;
        $this->_loadStorage();

        // Check if using challenge response
        (isset($this->post['authsecret']) && $this->post['authsecret'] == 1)
            ? $usingChap = true
            : $usingChap = false;


        // When the user has already entered a username, we have to validate it.
        if (!empty($this->username)) {
            if (true === $this->storage->fetchData($this->username, $this->password, $usingChap)) {
                $this->session['challengekey'] = md5($this->username.$this->password);
                $login_ok = true;
                $this->log('Successful login.', AUTH_LOG_INFO);
            }
        }

        if (!empty($this->username) && $login_ok) {
            $this->setAuth($this->username);
            if (is_callable($this->loginCallback)) {
                $this->log('Calling loginCallback ('.$this->loginCallback.').', AUTH_LOG_DEBUG);
                call_user_func_array($this->loginCallback, array($this->username, &$this));
            }
        }

        // If the login failed or the user entered no username,
        // output the login screen again.
        if (!empty($this->username) && !$login_ok) {
            $this->log('Incorrect login.', AUTH_LOG_INFO);
            $this->status = AUTH_WRONG_LOGIN;
            if (is_callable($this->loginFailedCallback)) {
                $this->log('Calling loginFailedCallback ('.$this->loginFailedCallback.').', AUTH_LOG_DEBUG);
                call_user_func_array($this->loginFailedCallback, array($this->username, &$this));
            }
        }

        if ((empty($this->username) || !$login_ok) && $this->showLogin) {
            $this->log('Rendering Login Form.', AUTH_LOG_INFO);
            if (is_callable($this->loginFunction)) {
                $this->log('Calling loginFunction ('.$this->loginFunction.').', AUTH_LOG_DEBUG);
                call_user_func_array($this->loginFunction, array($this->username, $this->status, &$this));
            } else {
                // BC fix Auth used to use drawLogin for this
                // call is sub classes implement this
                if (is_callable(array($this, 'drawLogin'))) {
                    $this->log('Calling Auth::drawLogin()', AUTH_LOG_DEBUG);
                    return $this->drawLogin($this->username, $this);
                }

                $this->log('Using default Auth_Frontend_Html', AUTH_LOG_DEBUG);

                // New Login form
                include_once 'Auth/Frontend/Html.php';
                return Auth_Frontend_Html::render($this, $this->username);
            }
        } else {
            return;
        }
    }

    // }}}
    // {{{ setExpire()

    function setExpire($time, $add = false)
    {
        $add ? $this->expire += $time : $this->expire = $time;
    }

    // }}}
    // {{{ setIdle()

    function setIdle($time, $add = false)
    {
        $add ? $this->idle += $time : $this->idle = $time;
    }

    // }}}
    // {{{ setSessionName()

    function setSessionName($name = 'session')
    {
        $this->_sessionName = '_auth_'.$name;
        // Make Sure Auth session variable is there
        if(!isset($_SESSION[$this->_sessionName])) {
            $_SESSION[$this->_sessionName] = array();
        }
        $this->session =& $_SESSION[$this->_sessionName];
    }

    // }}}
    // {{{ setShowLogin()

    function setShowLogin($showLogin = true)
    {
        $this->showLogin = $showLogin;
    }

    // }}}
    // {{{ setAllowLogin()

    function setAllowLogin($allowLogin = true)
    {
        $this->allowLogin = $allowLogin;
    }

    // }}}
    // {{{ setCheckAuthCallback()

    function setCheckAuthCallback($checkAuthCallback)
    {
        $this->checkAuthCallback = $checkAuthCallback;
    }

    // }}}
    // {{{ setLoginCallback()

    function setLoginCallback($loginCallback)
    {
        $this->loginCallback = $loginCallback;
    }

    // }}}
    // {{{ setFailedLoginCallback()

    function setFailedLoginCallback($loginFailedCallback)
    {
        $this->loginFailedCallback = $loginFailedCallback;
    }

    // }}}
    // {{{ setLogoutCallback()

    function setLogoutCallback($logoutCallback)
    {
        $this->logoutCallback = $logoutCallback;
    }

    // }}}
    // {{{ setAuthData()

    function setAuthData($name, $value, $overwrite = true)
    {
        if (!empty($this->session['data'][$name]) && $overwrite == false) {
            return;
        }
        $this->session['data'][$name] = $value;
    }

    // }}}
    // {{{ getAuthData()

    function getAuthData($name = null)
    {
        if (!isset($this->session['data'])) {
            return null;
        }
        if(!isset($name)) {
            return $this->session['data'];
        }
        if (isset($name) && isset($this->session['data'][$name])) {
            return $this->session['data'][$name];
        }
        return null;
    }

    // }}}
    // {{{ setAuth()

    function setAuth($username)
    {
        $this->log('Auth::setAuth() called.', AUTH_LOG_DEBUG);

        // #10729 - Regenerate session id here only if generating at login only
        //          Don't do it if we are regenerating on every request so we don't
        //          regenerate it twice in one request.
        if (!$this->regenerateSessionId) {
            // #2021 - Change the session id to avoid session fixation attacks php 4.3.3 >
            session_regenerate_id(true);
        }

        if (!isset($this->session) || !is_array($this->session)) {
            $this->session = array();
        }

        if (!isset($this->session['data'])) {
            $this->session['data'] = array();
        }

        $this->session['sessionip'] = isset($this->server['REMOTE_ADDR'])
            ? $this->server['REMOTE_ADDR']
            : '';
        $this->session['sessionuseragent'] = isset($this->server['HTTP_USER_AGENT'])
            ? $this->server['HTTP_USER_AGENT']
            : '';
        $this->session['sessionforwardedfor'] = isset($this->server['HTTP_X_FORWARDED_FOR'])
            ? $this->server['HTTP_X_FORWARDED_FOR']
            : '';

        // This should be set by the container to something more safe
        // Like md5(passwd.microtime)
        if(empty($this->session['challengekey'])) {
            $this->session['challengekey'] = md5($username.microtime());
        }

        $this->session['challengecookie'] = md5($this->session['challengekey'].microtime());
        setcookie('authchallenge', $this->session['challengecookie'], 0, '/');

        $this->session['registered'] = true;
        $this->session['username']   = $username;
        $this->session['timestamp']  = time();
        $this->session['idle']       = time();
    }

    // }}}
    // {{{ setAdvancedSecurity()

    function setAdvancedSecurity($flag=true)
    {
        $this->advancedsecurity = $flag;
    }

    // }}}
    // {{{ checkAuth()

    function checkAuth()
    {
        $this->log('Auth::checkAuth() called.', AUTH_LOG_DEBUG);
        $this->authChecks++;
        if (isset($this->session)) {
            // Check if authentication session is expired
            if (   $this->expire > 0
                && isset($this->session['timestamp'])
                && ($this->session['timestamp'] + $this->expire) < time()) {
                $this->log('Session Expired', AUTH_LOG_INFO);
                $this->expired = true;
                $this->status = AUTH_EXPIRED;
                $this->logout();
                return false;
            }

            // Check if maximum idle time is reached
            if (   $this->idle > 0
                && isset($this->session['idle'])
                && ($this->session['idle'] + $this->idle) < time()) {
                $this->log('Session Idle Time Reached', AUTH_LOG_INFO);
                $this->idled = true;
                $this->status = AUTH_IDLED;
                $this->logout();
                return false;
            }

            if (   isset($this->session['registered'])
                && isset($this->session['username'])
                && $this->session['registered'] == true
                && $this->session['username'] != '') {
                Auth::updateIdle();

                if ($this->_isAdvancedSecurityEnabled()) {
                    $this->log('Advanced Security Mode Enabled.', AUTH_LOG_DEBUG);

                    // Only Generate the challenge once
                    if (   $this->authChecks == 1
                        && $this->_isAdvancedSecurityEnabled(AUTH_ADV_CHALLENGE)) {
                        $this->log('Generating new Challenge Cookie.', AUTH_LOG_DEBUG);
                        $this->session['challengecookieold'] = $this->session['challengecookie'];
                        $this->session['challengecookie'] = md5($this->session['challengekey'].microtime());
                        setcookie('authchallenge', $this->session['challengecookie'], 0, '/');
                    }

                    // Check for ip change
                    if (   $this->_isAdvancedSecurityEnabled(AUTH_ADV_IPCHECK)
                        && isset($this->server['REMOTE_ADDR'])
                        && $this->session['sessionip'] != $this->server['REMOTE_ADDR']) {
                        $this->log('Security Breach. Remote IP Address changed.', AUTH_LOG_INFO);
                        // Check if the IP of the user has changed, if so we
                        // assume a man in the middle attack and log him out
                        $this->expired = true;
                        $this->status = AUTH_SECURITY_BREACH;
                        $this->logout();
                        return false;
                    }

                    // Check for ip change (if connected via proxy)
                    if (   $this->_isAdvancedSecurityEnabled(AUTH_ADV_IPCHECK)
                        && isset($this->server['HTTP_X_FORWARDED_FOR'])
                        && $this->session['sessionforwardedfor'] != $this->server['HTTP_X_FORWARDED_FOR']) {
                        $this->log('Security Breach. Forwarded For IP Address changed.', AUTH_LOG_INFO);
                        // Check if the IP of the user connecting via proxy has
                        // changed, if so we assume a man in the middle attack
                        // and log him out.
                        $this->expired = true;
                        $this->status = AUTH_SECURITY_BREACH;
                        $this->logout();
                        return false;
                    }

                    // Check for useragent change
                    if (   $this->_isAdvancedSecurityEnabled(AUTH_ADV_USERAGENT)
                        && isset($this->server['HTTP_USER_AGENT'])
                        && $this->session['sessionuseragent'] != $this->server['HTTP_USER_AGENT']) {
                        $this->log('Security Breach. User Agent changed.', AUTH_LOG_INFO);
                        // Check if the User-Agent of the user has changed, if
                        // so we assume a man in the middle attack and log him out
                        $this->expired = true;
                        $this->status = AUTH_SECURITY_BREACH;
                        $this->logout();
                        return false;
                    }

                    // Check challenge cookie here, if challengecookieold is not set
                    // this is the first time and check is skipped
                    // TODO when user open two pages similtaneuly (open in new window,open
                    // in tab) auth breach is caused find out a way around that if possible
                    if (   $this->_isAdvancedSecurityEnabled(AUTH_ADV_CHALLENGE)
                        && isset($this->session['challengecookieold'])
                        && $this->session['challengecookieold'] != $this->cookie['authchallenge']) {
                        $this->log('Security Breach. Challenge Cookie mismatch.', AUTH_LOG_INFO);
                        $this->expired = true;
                        $this->status = AUTH_SECURITY_BREACH;
                        $this->logout();
                        $this->login();
                        return false;
                    }
                }

                if (is_callable($this->checkAuthCallback)) {
                    $this->log('Calling checkAuthCallback ('.$this->checkAuthCallback.').', AUTH_LOG_DEBUG);
                    $checkCallback = call_user_func_array($this->checkAuthCallback, array($this->username, &$this));
                    if ($checkCallback == false) {
                        $this->log('checkAuthCallback failed.', AUTH_LOG_INFO);
                        $this->expired = true;
                        $this->status = AUTH_CALLBACK_ABORT;
                        $this->logout();
                        return false;
                    }
                }

                $this->log('Session OK.', AUTH_LOG_INFO);
                return true;
            }
        } else {
            $this->log('Unable to locate session storage.', AUTH_LOG_DEBUG);
            return false;
        }
        $this->log('No login session.', AUTH_LOG_DEBUG);
        return false;
    }

    // }}}
    // {{{ staticCheckAuth() [static]

    function staticCheckAuth($options = null)
    {
        static $staticAuth;
        if(!isset($staticAuth)) {
            $staticAuth = new Auth('null', $options);
        }
        $staticAuth->log('Auth::staticCheckAuth() called', AUTH_LOG_DEBUG);
        return $staticAuth->checkAuth();
    }

    // }}}
    // {{{ getAuth()

    function getAuth()
    {
        $this->log('Auth::getAuth() called.', AUTH_LOG_DEBUG);
        return $this->checkAuth();
    }

    // }}}
    // {{{ logout()

    function logout()
    {
        $this->log('Auth::logout() called.', AUTH_LOG_DEBUG);

        if (is_callable($this->logoutCallback) && isset($this->session['username'])) {
            $this->log('Calling logoutCallback ('.$this->logoutCallback.').', AUTH_LOG_DEBUG);
            call_user_func_array($this->logoutCallback, array($this->session['username'], &$this));
        }

        $this->username = '';
        $this->password = '';

        $this->session = null;
    }

    // }}}
    // {{{ updateIdle()

    function updateIdle()
    {
        $this->session['idle'] = time();
    }

    // }}}
    // {{{ getUsername()

    function getUsername()
    {
        if (isset($this->session['username'])) {
            return($this->session['username']);
        }
        return('');
    }

    // }}}
    // {{{ getStatus()

    function getStatus()
    {
        return $this->status;
    }

    // }}}
    // {{{ getPostUsernameField()

    function getPostUsernameField()
    {
        return($this->_postUsername);
    }

    // }}}
    // {{{ getPostPasswordField()

    function getPostPasswordField()
    {
        return($this->_postPassword);
    }

    // }}}
    // {{{ sessionValidThru()

    function sessionValidThru()
    {
        if (!isset($this->session['idle'])) {
            return 0;
        }
        if ($this->idle == 0) {
            return 0;
        }
        return ($this->session['idle'] + $this->idle);
    }

    // }}}
    // {{{ listUsers()

    function listUsers()
    {
        $this->log('Auth::listUsers() called.', AUTH_LOG_DEBUG);
        $this->_loadStorage();
        return $this->storage->listUsers();
    }

    // }}}
    // {{{ addUser()

    function addUser($username, $password, $additional = '')
    {
        $this->log('Auth::addUser() called.', AUTH_LOG_DEBUG);
        $this->_loadStorage();
        return $this->storage->addUser($username, $password, $additional);
    }

    // }}}
    // {{{ removeUser()

    function removeUser($username)
    {
        $this->log('Auth::removeUser() called.', AUTH_LOG_DEBUG);
        $this->_loadStorage();
        return $this->storage->removeUser($username);
    }

    // }}}
    // {{{ changePassword()

    function changePassword($username, $password)
    {
        $this->log('Auth::changePassword() called', AUTH_LOG_DEBUG);
        $this->_loadStorage();
        return $this->storage->changePassword($username, $password);
    }

    // }}}
    // {{{ log()

    function log($message, $level = AUTH_LOG_DEBUG)
    {
        if (!$this->enableLogging) return false;

        $this->_loadLogger();

        $this->logger->log('AUTH: '.$message, $level);
    }

    // }}}
    // {{{ _loadLogger()

    function _loadLogger()
    {
        if(is_null($this->logger)) {
            if (!class_exists('Log')) {
                include_once 'Log.php';
            }
            $this->logger =& Log::singleton('null',
                    null,
                    'auth['.getmypid().']',
                    array(),
                    AUTH_LOG_DEBUG);
            return(true);
        }
        return(false);
    }

    // }}}
    // {{{ attachLogObserver()

    function attachLogObserver(&$observer) {

        $this->_loadLogger();

        return $this->logger->attach($observer);

    }

    // }}}
    // {{{ _isAdvancedSecurityEnabled()

    function _isAdvancedSecurityEnabled($feature = null) {

        if (is_null($feature)) {

            if ($this->advancedsecurity === true)
                return true;

            if (   is_array($this->advancedsecurity)
                && in_array(true, $this->advancedsecurity, true))
                return true;

            return false;

        } else {

            if (is_array($this->advancedsecurity)) {

                if (   isset($this->advancedsecurity[$feature])
                    && $this->advancedsecurity[$feature] == true)
                    return true;

                return false;

            }

            return (bool)$this->advancedsecurity;

        }

    }

    // }}}

}
?>