mirror of
https://github.com/EGroupware/egroupware.git
synced 2024-11-29 19:33:54 +01:00
71 lines
2.5 KiB
PHP
71 lines
2.5 KiB
PHP
|
<?php
|
||
|
|
/**
|
||
|
|
* EGroupware API: CSRF (Cross Site Request Forgery) protection
|
||
|
|
*
|
||
|
|
* @link http://www.egroupware.org
|
||
|
|
* @license http://opensource.org/licenses/gpl-license.php GPL - GNU General Public License
|
||
|
|
* @package api
|
||
|
|
* @author Ralf Becker <rb@stylite.de>
|
||
|
|
* @copyright (c) 2014 by Ralf Becker <rb@stylite.de>
|
||
|
|
* @version $Id$
|
||
|
|
*/
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Class supplying methods to prevent successful CSRF by requesting a random token,
|
||
|
|
* stored on server and validated when request get posted.
|
||
|
|
*
|
||
|
|
* CSRF token generation used openssl_random_pseudo_bytes, if available, otherwise
|
||
|
|
* mt_rand based auth::randomstring is used.
|
||
|
|
*
|
||
|
|
* CSRF tokens are stored (incl. optional purpose) in user session.
|
||
|
|
*
|
||
|
|
* If a token does not validate (incl. purpose, if specified in generation)
|
||
|
|
* the request will be imediatly terminated.
|
||
|
|
*/
|
||
|
|
class egw_csrf
|
||
|
|
{
|
||
|
|
/**
|
||
|
|
* Get a CSRF token for an optional $purpose, which can be validated
|
||
|
|
*
|
||
|
|
* @param mixed $_purpose=true if given it need to be used in validate too! (It must NOT be NULL)
|
||
|
|
* @return string CSRF token
|
||
|
|
*/
|
||
|
|
public static function token($_purpose=true)
|
||
|
|
{
|
||
|
|
if (is_null($_purpose))
|
||
|
|
{
|
||
|
|
throw new egw_exception_wrong_parameter(__METHOD__.'(NULL) $_purspose must NOT be NULL!');
|
||
|
|
}
|
||
|
|
// generate random token (using oppenssl if available otherwise mt_rand based auth::randomstring)
|
||
|
|
$token = function_exists('openssl_random_pseudo_bytes') ?
|
||
|
|
base64_encode(openssl_random_pseudo_bytes(64)) :
|
||
|
|
auth::randomstring(64);
|
||
|
|
|
||
|
|
// store it in session for later validation
|
||
|
|
egw_cache::setSession(__CLASS__, $token, $_purpose);
|
||
|
|
|
||
|
|
return $token;
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Validate a CSRF token or teminate the request
|
||
|
|
*
|
||
|
|
* @param string $_token CSRF token generated with egw_csfr::token()
|
||
|
|
* @param string $_purpose=true optional purpose string passed to token method
|
||
|
|
* @param boolean $_delete_token=true true if token should be deleted after validation, it will validate no second time
|
||
|
|
*/
|
||
|
|
public static function validate($_token, $_purpose=true, $_delete_token=true)
|
||
|
|
{
|
||
|
|
$stored_purpose = egw_cache::getSession(__CLASS__, $_token);
|
||
|
|
|
||
|
|
// if token and purpose dont validate, log and terminate request
|
||
|
|
if (!isset($stored_purpose) || $stored_purpose !== $_purpose)
|
||
|
|
{
|
||
|
|
error_log('CSRF detected from IP '.$_SERVER['REMOTE_ADDR'].' to '.$_SERVER['REQUEST_METHOD'].' '.$_SERVER['REQUEST_URI']);
|
||
|
|
if ($_POST) error_log(array2string($_POST));
|
||
|
|
// we are not throwing an exception here, but die, to not allow catching it!
|
||
|
|
die("CSRF detected, request terminated!");
|
||
|
|
}
|
||
|
|
if ($_delete_token) egw_cache::unsetTree (__CLASS__, $_token);
|
||
|
|
}
|
||
|
|
}
|