Файл: framework/core/startup/ParameterConfirmationToken.php
Строк: 289
<?php
/**
* Class ParameterConfirmationToken
*
* When you need to use a dangerous GET parameter that needs to be set before core/Core.php is
* established, this class takes care of allowing some other code of confirming the parameter,
* by generating a one-time-use token & redirecting with that token included in the redirected URL
*
* WARNING: This class is experimental and designed specifically for use pre-startup in main.php
* It will likely be heavily refactored before the release of 3.2
*
* @package framework
* @subpackage misc
*/
class ParameterConfirmationToken {
/**
* The name of the parameter
*
* @var string
*/
protected $parameterName = null;
/**
* The parameter given
*
* @var string|null The string value, or null if not provided
*/
protected $parameter = null;
/**
* The validated and checked token for this parameter
*
* @var string|null A string value, or null if either not provided or invalid
*/
protected $token = null;
protected function pathForToken($token) {
return TEMP_FOLDER.'/token_'.preg_replace('/[^a-z0-9]+/', '', $token);
}
/**
* Generate a new random token and store it
*
* @return string Token name
*/
protected function genToken() {
// Generate a new random token (as random as possible)
require_once(dirname(dirname(dirname(__FILE__))).'/security/RandomGenerator.php');
$rg = new RandomGenerator();
$token = $rg->randomToken('md5');
// Store a file in the session save path (safer than /tmp, as open_basedir might limit that)
file_put_contents($this->pathForToken($token), $token);
return $token;
}
/**
* Validate a token
*
* @param string $token
* @return boolean True if the token is valid
*/
protected function checkToken($token) {
if(!$token) {
return false;
}
$file = $this->pathForToken($token);
$content = null;
if (file_exists($file)) {
$content = file_get_contents($file);
unlink($file);
}
return $content == $token;
}
/**
* Create a new ParameterConfirmationToken
*
* @param string $parameterName Name of the querystring parameter to check
*/
public function __construct($parameterName) {
// Store the parameter name
$this->parameterName = $parameterName;
// Store the parameter value
$this->parameter = isset($_GET[$parameterName]) ? $_GET[$parameterName] : null;
// If the token provided is valid, mark it as such
$token = isset($_GET[$parameterName.'token']) ? $_GET[$parameterName.'token'] : null;
if ($this->checkToken($token)) {
$this->token = $token;
}
}
/**
* Get the name of this token
*
* @return string
*/
public function getName() {
return $this->parameterName;
}
/**
* Is the parameter requested?
* ?parameter and ?parameter=1 are both considered requested
*
* @return bool
*/
public function parameterProvided() {
return $this->parameter !== null;
}
/**
* Is the necessary token provided for this parameter?
* A value must be provided for the token
*
* @return bool
*/
public function tokenProvided() {
return !empty($this->token);
}
/**
* Is this parameter requested without a valid token?
*
* @return bool True if the parameter is given without a valid token
*/
public function reloadRequired() {
return $this->parameterProvided() && !$this->tokenProvided();
}
/**
* Suppress the current parameter by unsetting it from $_GET
*/
public function suppress() {
unset($_GET[$this->parameterName]);
}
/**
* Determine the querystring parameters to include
*
* @return array List of querystring parameters with name and token parameters
*/
public function params() {
return array(
$this->parameterName => $this->parameter,
$this->parameterName.'token' => $this->genToken()
);
}
/** What to use instead of BASE_URL. Must not contain protocol or host. @var string */
static public $alternateBaseURL = null;
protected function currentAbsoluteURL() {
global $url;
// Are we http or https? Replicates Director::is_https() without its dependencies/
$proto = 'http';
// See https://en.wikipedia.org/wiki/List_of_HTTP_header_fields
// See https://support.microsoft.com/?kbID=307347
$headerOverride = false;
if(TRUSTED_PROXY) {
$headers = (defined('SS_TRUSTED_PROXY_PROTOCOL_HEADER')) ? array(SS_TRUSTED_PROXY_PROTOCOL_HEADER) : null;
if(!$headers) {
// Backwards compatible defaults
$headers = array('HTTP_X_FORWARDED_PROTO', 'HTTP_X_FORWARDED_PROTOCOL', 'HTTP_FRONT_END_HTTPS');
}
foreach($headers as $header) {
$headerCompareVal = ($header === 'HTTP_FRONT_END_HTTPS' ? 'on' : 'https');
if(!empty($_SERVER[$header]) && strtolower($_SERVER[$header]) == $headerCompareVal) {
$headerOverride = true;
break;
}
}
}
if($headerOverride) {
$proto = 'https';
} else if((!empty($_SERVER['HTTPS']) && $_SERVER['HTTPS'] != 'off')) {
$proto = 'https';
} else if(isset($_SERVER['SSL'])) {
$proto = 'https';
}
$parts = array_filter(array(
// What's our host
$_SERVER['HTTP_HOST'],
// SilverStripe base
self::$alternateBaseURL !== null ? self::$alternateBaseURL : BASE_URL,
// And URL
$url
));
// Join together with protocol into our current absolute URL, avoiding duplicated "/" characters
return "$proto://" . preg_replace('#/{2,}#', '/', implode('/', $parts));
}
/**
* Forces a reload of the request with the token included
* This method will terminate the script with `die`
*/
public function reloadWithToken() {
$location = $this->currentAbsoluteURL();
// What's our GET params (ensuring they include the original parameter + a new token)
$params = array_merge($_GET, $this->params());
unset($params['url']);
if ($params) $location .= '?'.http_build_query($params);
// And redirect
if (headers_sent()) {
echo "
<script>location.href='$location';</script>
<noscript><meta http-equiv='refresh' content='0; url=$location'></noscript>
You are being redirected. If you are not redirected soon, <a href='$location'>click here to continue the flush</a>
";
}
else header('location: '.$location, true, 302);
die;
}
/**
* Given a list of token names, suppress all tokens that have not been validated, and
* return the non-validated token with the highest priority
*
* @param array $keys List of token keys in ascending priority (low to high)
* @return ParameterConfirmationToken The token container for the unvalidated $key given with the highest priority
*/
public static function prepare_tokens($keys) {
$target = null;
foreach($keys as $key) {
$token = new ParameterConfirmationToken($key);
// Validate this token
if($token->reloadRequired()) {
$token->suppress();
$target = $token;
}
}
return $target;
}
}