Files
FHC-Core/application/libraries/AuthLib.php
T

611 lines
20 KiB
PHP

<?php
if (!defined('BASEPATH')) exit('No direct script access allowed');
class AuthLib
{
// Config entry name
const LOGOUT_PAGE = 'system/Logout';
// Config entry name
const AUTHENTICATION_FOREIGN_METHODS = 'authentication_foreign_methods';
const AUTHENTICATION_LOGIN = 'authentication_login';
const AUTHENTICATION_LOGIN_PAGES = 'authentication_login_pages';
const AUTHENTICATION_LOGOUT_PAGE = 'authentication_logout_page';
// Login object properties
const AO_PERSON_ID = 'person_id';
const AO_NAME = 'name';
const AO_SURNAME = 'surname';
const AO_USERNAME = 'username';
// Sessions names
const SESSION_NAME = 'AUTH';
const SESSION_AUTH_OBJ = 'AUTH_OBJ';
const SESSION_AUTH_OBJ_ORIGIN = 'AUTH_OBJ_ORIGIN';
const SESSION_LANDING_PAGE = 'LANDING_PAGE';
private $_ci; // CI instance
/**
* Construct
*
* @param bool $authenticate If the authentication must be performed.
*/
public function __construct($authenticate = true)
{
// Gets CI instance
$this->_ci =& get_instance();
if ($authenticate === true) $this->_authenticate(); // if required -> authenticate the current user
}
//------------------------------------------------------------------------------------------------------------------
// Public methods
/**
* Returns the authentication object stored in the session
* if the user is not logged then returns null
*/
public function getAuthObj()
{
return getSessionElement(self::SESSION_NAME, self::SESSION_AUTH_OBJ);
}
/**
* The logged user is able, if it is allowed, to get the identity of another user by its given uid
*/
public function loginASByUID($uid)
{
$loginAS = error('Not authenticated', AUTH_NOT_AUTHENTICATED); // not authenticated by default
// A user must be already logged
if ($this->_isLogged())
{
// - The uid must be NOT an empty string
// - The current user should NOT be already logged as the given uid
if (!isEmptyString($uid) && $this->getAuthObj()->username != $uid)
{
$this->_ci->load->library('PermissionLib'); // Loads permissions library
// Checks if the logged user is allowed to obtain the new identity
if ($this->_ci->permissionlib->isEntitledLoginASByUID($uid))
{
// Create the authentication object with new identity data
$loginAS = $this->_createAuthObjByPerson(array('uid' => $uid));
if (isSuccess($loginAS))
{
// Store the new authentication object in authentication session
setSessionElement(self::SESSION_NAME, self::SESSION_AUTH_OBJ, getData($loginAS));
}
}
else
{
$loginAS = error('It is not allowed to switch to this user', AUTH_NOT_AUTHENTICATED); // not authenticated by default
}
}
else
{
$loginAS = error('The given uid is not valid', AUTH_INVALID_CREDENTIALS);
}
}
return $loginAS;
}
/**
* The logged user is able, if it is allowed, to get the identity of another user by its given person id
*/
public function loginASByPersonId($person_id)
{
$loginAS = error('Not authenticated', AUTH_NOT_AUTHENTICATED); // not authenticated by default
// A user must be already logged
if ($this->_isLogged())
{
// - The person id must be a number
// - The current user should NOT be already logged as the given person id
if (is_numeric($person_id) && $this->getAuthObj()->person_id != $person_id)
{
$this->_ci->load->library('PermissionLib'); // Loads permissions library
// Checks if the logged user is allowed to obtain the new identity by its person id
if ($this->_ci->permissionlib->isEntitledLoginASByPersonId($person_id))
{
// Create the authentication object with new identity data
$loginAS = $this->_createAuthObjByPerson(array('person_id' => $person_id));
if (isSuccess($loginAS)) // if successfully created
{
$authObj = getData($loginAS); // get the authenticate object
if ($authObj->{self::AO_USERNAME} != null) // if the username is present
{
// Checks if the logged user is allowed to obtain the new identity by its uid
if ($this->_ci->permissionlib->isEntitledLoginASByUID($authObj->{self::AO_USERNAME}))
{
// Store the new authentication object in authentication session
setSessionElement(self::SESSION_NAME, self::SESSION_AUTH_OBJ, $authObj);
}
else // if does NOT have permissions
{
$loginAS = error('Not authenticated', AUTH_NOT_AUTHENTICATED);
}
}
else // otherwise it's NOT possible to check other permissions
{
// Store the new authentication object in authentication session
setSessionElement(self::SESSION_NAME, self::SESSION_AUTH_OBJ, $authObj);
}
}
}
}
else
{
$loginAS = error('The given person id is not valid', AUTH_INVALID_CREDENTIALS);
}
}
return $loginAS;
}
/**
* Logs out the current logged user
* If the user is using the LoginAs functionality then it is logged out from the acquired user
* and its original one is restored
*/
public function logout()
{
$authObj = getSessionElement(self::SESSION_NAME, self::SESSION_AUTH_OBJ);
$authObjOrigin = getSessionElement(self::SESSION_NAME, self::SESSION_AUTH_OBJ_ORIGIN);
// NOT logged in
if ($authObj == null || $authObjOrigin == null) return;
// LoginAs functionality NOT in use
if ($authObj->{self::AO_PERSON_ID} == $authObjOrigin->{self::AO_PERSON_ID})
{
// Clean the entire session -> fully logged out
cleanSession(self::SESSION_NAME);
}
else // loginAs functionality in use
{
// Copy the origin authentication object as the authentication object in session
// The LoginAs account is logged out
// The user is again connected with its real account
setSessionElement(self::SESSION_NAME, self::SESSION_AUTH_OBJ, $authObjOrigin);
}
}
/**
* Login a user with the given username and password using LDAP
*/
public function loginLDAP($username, $password)
{
// If already logged do NOT check another time, returns the authentication object
if ($this->_isLogged()) return success($this->getAuthObj(), AUTH_SUCCESS);
// Otherwise checks the given credentials
$loginUP = $this->_checkLDAPAuthentication($username, $password);
if (isSuccess($loginUP))
{
$loginUP = $this->_createAuthObjByPerson(array('uid' => $username));
// If were possible to retrieve user's data without failing,
// then stores the authentication object into authentication session
if (isSuccess($loginUP)) $this->_storeSessionAuthObj(getData($loginUP));
}
return $loginUP;
}
/**
* Redirect to the previously stored landing page
*/
public function redirectToLandingPage($altLandingPage = null)
{
$this->_redirectTemporarily($this->getLandingPage($altLandingPage)); // redirect to landing page
}
/**
* Returns the landing page
*/
public function getLandingPage($altLandingPage = null)
{
// Tries to get the previously stored landing page
$landingPage = getSessionElement(self::SESSION_NAME, self::SESSION_LANDING_PAGE);
if ($landingPage == null) // if not present
{
// If it was given a valid alternative landing page
if (!isEmptyString($altLandingPage))
{
$landingPage = $altLandingPage;
}
else
{
$landingPage = site_url(); // use the default home page
}
}
// Clean the previously stored landing page
cleanSessionElement(self::SESSION_NAME, self::SESSION_LANDING_PAGE);
return $landingPage;
}
/**
* Checks the authentication of an addon. Returns TRUE if valid, otherwise FALSE
*/
public function basicAuthentication($username, $password)
{
return isSuccess($this->loginLDAP($username, $password));
}
/**
* Checks if the given username and password of a final user are valid
*/
public function checkUserAuthByUsernamePassword($username, $password, $keys = false)
{
$result = error(false);
if (isset($username) && isset($password))
{
if (isSuccess($this->_checkLDAPAuthentication($username, $password)))
{
if ($keys === true)
{
$result = $this->_getFinalUserBasicDataByUID($username);
}
else
{
$result = success(true);
}
}
}
return $result;
}
//------------------------------------------------------------------------------------------------------------------
// Private methods
/**
* Create an authentication object with all the information about the logged user
* The minimum information required is the person_id
* Username should be null only if the user is authenticated with a foreign authentication method
*/
private function _createAuthObj($person_id, $name = null, $surname = null, $username = null)
{
$authObj = null;
if (is_numeric($person_id))
{
$authObj = new stdClass();
$authObj->{self::AO_PERSON_ID} = $person_id;
$authObj->{self::AO_USERNAME} = $username;
$authObj->{self::AO_SURNAME} = $surname;
$authObj->{self::AO_NAME} = $name;
}
return $authObj;
}
/**
* If the object store in $_SESSIOn['AUTH']['AUTH_OBJ']
* is NOT null (logged) then returns true otherwise false (NOT logged)
*/
private function _isLogged()
{
return $this->getAuthObj() != null;
}
/**
* Display an invalid credentials error
* Used only by HTTP basic authentication!
*/
private function _showInvalidAuthentication()
{
$this->_ci->output->set_status_header(REST_Controller::HTTP_UNAUTHORIZED); // set the HTTP header as unauthorized
unset($_SERVER['PHP_AUTH_USER']);
$this->_ci->load->library('EPrintfLib'); // loads the EPrintfLib to format the output
// Prints the main error message
$this->_ci->eprintflib->printError('The provided authentication credentials are invalid');
// Prints the called controller name
$this->_ci->eprintflib->printInfo('Controller name: '.$this->_ci->router->class);
// Prints the called controller method name
$this->_ci->eprintflib->printInfo('Method name: '.$this->_ci->router->method);
exit; // immediately terminate the execution
}
/**
* Display a generic blocking error occurred while authenticating the user
*/
private function _showError($errorMessage)
{
$this->_ci->output->set_status_header(REST_Controller::HTTP_UNAUTHORIZED); // set the HTTP header as unauthorized
$this->_ci->load->library('EPrintfLib'); // loads the EPrintfLib to format the output
$this->_ci->load->library('LogLib'); // Loads the logs library
// Prints the main error message
$this->_ci->eprintflib->printError('An error occurred while checking the provided credentials');
$this->_ci->eprintflib->printError('Please contact the system administrator');
// Prints the called controller name
$this->_ci->eprintflib->printInfo('Controller name: '.$this->_ci->router->class);
// Prints the called controller method name
$this->_ci->eprintflib->printInfo('Method name: '.$this->_ci->router->method);
// Prints date and time
$this->_ci->eprintflib->printInfo('Date and time: '.date('Y.m.d H:i:s'));
$this->_ci->loglib->logError($errorMessage); // CI log error
exit; // immediately terminate the execution
}
/**
* Checks if the user is already authenticated with the Bewerbung Tool
* NOTE: this method does NOT set the username in the authentication object
*/
private function _checkBTAuthentication()
{
$bt = error('Not authenticated', AUTH_NOT_AUTHENTICATED); // by default is NOT authenticated
// Checks if an authentication were performed via BT
if (isset($_SESSION['bewerbung/personId']) && is_numeric($_SESSION['bewerbung/personId']) && isset($_SESSION['bewerbung/user']))
{
$bt = $this->_createAuthObjByPerson(array('person_id' => $_SESSION['bewerbung/personId']));
}
return $bt;
}
/**
* Checks if the user is already authenticated with HTTP basic authentication + LDAP
* NOTE: this method also display a login, not possible to be avoided due HTTP basic authentication limitations
*/
private function _checkHBALDAPAuthentication()
{
$hta = error('Not authenticated', AUTH_NOT_AUTHENTICATED); // by default is NOT authenticated
// Checks if an HTTP basic authentication is active and checks credentials using LDAP
if (!isset($_SERVER['PHP_AUTH_USER'])
|| isError($hta = $this->_checkLDAPAuthentication($_SERVER['PHP_AUTH_USER'], $_SERVER['PHP_AUTH_PW'])))
{
// If NOT send the header to perform an HTTP basic authentication
header('WWW-Authenticate: Basic realm="'.AUTH_NAME.'"');
}
else // otherwise
{
// NOTE: Username needs to be trimmed and lowered because htaccess is allowing login
$hta = $this->_createAuthObjByPerson(array('uid' => mb_strtolower(trim($_SERVER['PHP_AUTH_USER']))));
}
// Invalid credentials
// NOTE: this is a corner case because of the HTTP basic authentication
if (getCode($hta) == AUTH_NOT_AUTHENTICATED || getCode($hta) == AUTH_INVALID_CREDENTIALS
|| getCode($hta) == AuthLDAPLib::LDAP_NO_USER_DN || getCode($hta) == AuthLDAPLib::LDAP_TOO_MANY_USER_DN)
{
$this->_showInvalidAuthentication(); // this also stop the execution
}
elseif (isError($hta)) // display error and stop execution
{
$this->_showError(getError($hta));
}
return $hta; // if success then is returned!
}
/**
* Checks the provided username and password with LDAP
*/
private function _checkLDAPAuthentication($username, $password)
{
$ldap = error('Not authenticated', AUTH_NOT_AUTHENTICATED); // by default is NOT authenticated
$this->_ci->load->library('AuthLDAPLib'); // Loads the LDAP library
// If it is possible to authenticate on LDAP with the given username and password
if ($this->_ci->authldaplib->checkUsernamePassword($username, $password) === true)
{
$ldap = success('Authenticated', AUTH_SUCCESS); // authenticated!
}
return $ldap;
}
/**
* Tries to find if the user is already logged via a foreign authentication method
* using a list of foreign authentication methods provided with the configurations
* If the user is logged via a foreign authentication method then an authentication object is returned
* NOTE: _checkHBALDAPAuthentication is the last to be called and it is a corner case due the HTTP basic
* authentication mechanism, and it does not return anything
*/
private function _checkForeignAuthentication()
{
$auth = error('Not authenticated', AUTH_NOT_AUTHENTICATED); // by default is NOT authenticated
$am = $this->_ci->config->item(self::AUTHENTICATION_FOREIGN_METHODS); // foreign authentication methods array
// Loops through the foreign authentication methods
foreach ($am as $method)
{
// Performs a different action for each foreign authentication method
switch ($method)
{
case AUTH_BT: // Bewerbung tool
$auth = $this->_checkBTAuthentication();
break;
case AUTH_HBALDAP: // HTTP basic authentication + LDAP
$auth = $this->_checkHBALDAPAuthentication();
break;
}
// If not authenticated with this method...
if (getCode($auth) == AUTH_NOT_AUTHENTICATED)
{
// ...then continue to the next one
}
// If generic error or a foreign authentication was found stop checking
elseif (isError($auth) || (hasData($auth) && is_object(getData($auth))))
{
break;
}
}
return $auth;
}
/**
* Stores the authentication object into the authentication session
* Everything was fine, the user at this point is authenticated, it is possible to store the authentication object
* in the user session
*/
private function _storeSessionAuthObj($authObj)
{
setSessionElement(self::SESSION_NAME, self::SESSION_AUTH_OBJ, $authObj); // authentication object
setSessionElement(self::SESSION_NAME, self::SESSION_AUTH_OBJ_ORIGIN, $authObj); // authentication original object
}
/**
* Stores the user accessed point into the authentication session
*/
private function _storeSessionLandingPage($loginPage, $logoutPage)
{
// Build the curret URL (user access point)
$currentURL = current_url().(!isEmptyString($_SERVER['QUERY_STRING']) ? '?'.$_SERVER['QUERY_STRING'] : '');
// If the access point is not the login page or the logout page
if ($currentURL != site_url($loginPage) && $currentURL != site_url($logoutPage))
{
setSessionElement(self::SESSION_NAME, self::SESSION_LANDING_PAGE, $currentURL);
}
}
/**
* Redirect the user's browser to the configured login page
*/
private function _redirectToLogin()
{
$al = $this->_ci->config->item(self::AUTHENTICATION_LOGIN); // selected login method
$alip = $this->_ci->config->item(self::AUTHENTICATION_LOGIN_PAGES); // login pages configuration array
$alop = $this->_ci->config->item(self::AUTHENTICATION_LOGOUT_PAGE); // logout page configuration
// If the configuration is valid
if (!isEmptyArray($alip) && isset($alip[$al]))
{
$this->_storeSessionLandingPage($alip[$al], $alop); // stores in session the user access point
$this->_redirectTemporarily(site_url($alip[$al])); // redirect to login page
}
else
{
$this->_showError('No valid login page was set'); // display a generic error message and logs the occurred error
}
}
/**
* Starts the user authentication!
*/
private function _authenticate()
{
// If NOT logged
if (!$this->_isLogged())
{
$this->_ci->config->load('auth'); // Loads auth configuration
// Checks if already logged with a foreign authentication method
$auth = $this->_checkForeignAuthentication();
if (hasData($auth)) // Authenticated with a foreign authentication method
{
$this->_storeSessionAuthObj(getData($auth)); // store the session authentication object
}
elseif (getCode($auth) == AUTH_NOT_AUTHENTICATED) // if no foreign authentication was found...
{
$this->_redirectToLogin(); // ...then redirect to login page
}
elseif (isError($auth)) // blocking error
{
$this->_showError(getError($auth)); // display a generic error message and logs the occurred error
}
}
// else the user is already logged, then loads authentication helper and continue with the execution
// NOTE: it is needed only here because:
// - it is called when a user is already logged in
// - it is called after login the user
// - it is NOT called in case of fatal error or wrong authentication
$this->_ci->load->helper('hlp_authentication');
}
/**
* It uses the given query where clause to select data for a user and then stores these data into a authentication object
*/
private function _createAuthObjByPerson($queryParamsArray)
{
$authObj = error('No user data found'); // pessimistic as usual
$this->_ci->load->model('person/person_model', 'PersonModel'); // Loads model PersonModel
$this->_ci->PersonModel->resetQuery(); // Reset an eventually already built query
// Needed information
$this->_ci->PersonModel->addSelect('person_id, vorname, nachname, uid');
// Retrieves the uid if it is possible for active users
$this->_ci->PersonModel->addJoin('public.tbl_benutzer', 'person_id', 'LEFT');
// Execute query with where clause
$personResult = $this->_ci->PersonModel->loadWhere($queryParamsArray);
if (hasData($personResult))
{
$person = getData($personResult)[0];
// Stores user data into the authentication object and then into a success object
$authObj = success(
$this->_createAuthObj($person->person_id, $person->vorname, $person->nachname, $person->uid),
AUTH_SUCCESS
);
}
elseif (isError($personResult)) // blocking error
{
$authObj = $personResult; // to be returned
}
return $authObj;
}
/**
* HTTP temporary redirection
*/
private function _redirectTemporarily($url)
{
// Temporary redirection
header('HTTP/1.1 302 Moved temporary');
header('Location: '.$url); // redirect to the given URL
exit(); // stops execution!
}
/**
* Returns all the keys with which is possible to obtain personal data about a final user
* using the given username (uid)
*/
private function _getFinalUserBasicDataByUID($uid)
{
$finalUserBasicDataByUID = null;
// Load model BenutzerModel
$this->_ci->load->model('person/Benutzer_model', 'BenutzerModel');
$benutzer = $this->_ci->BenutzerModel->load($uid);
if (hasData($benutzer))
{
$finalUserBasicDataByPersonID = new stdClass();
// Store the person_id and eventually all the uid and prestudent_id related to this final user
$finalUserBasicDataByPersonID->person_id = $benutzer->retval[0]->person_id;
$finalUserBasicDataByUID = success($finalUserBasicDataByPersonID);
}
return $finalUserBasicDataByUID;
}
}