This repository contains a Slim Framework CSRF protection middleware. CSRF protection applies to all unsafe HTTP requests (POST, PUT, DELETE, PATCH).
You can fetch the latest CSRF token's name and value from the Request object with its getAttribute()
method. By default, the CSRF token's name is stored in the csrf_name
attribute, and the CSRF token's value is stored in the csrf_value
attribute.
Via Composer
$ composer require slim/csrf
Requires Slim 3.0.0 or newer.
In most cases you want to register Slim\Csrf for all routes, however, as it is middleware, you can also register it for a subset of routes.
// Start PHP session
session_start();
$app = new \Slim\App();
// Register with container
$container = $app->getContainer();
$container['csrf'] = function ($c) {
return new \Slim\Csrf\Guard;
};
// Register middleware for all routes
// If you are implementing per-route checks you must not add this
$app->add($container->get('csrf'));
$app->get('/foo', function ($req, $res, $args) {
// CSRF token name and value
$nameKey = $this->csrf->getTokenNameKey();
$valueKey = $this->csrf->getTokenValueKey();
$name = $req->getAttribute($nameKey);
$value = $req->getAttribute($valueKey);
// Render HTML form which POSTs to /bar with two hidden input fields for the
// name and value:
// <input type="hidden" name="<?= $nameKey ?>" value="<?= $name ?>">
// <input type="hidden" name="<?= $valueKey ?>" value="<?= $value ?>">
});
$app->post('/bar', function ($req, $res, $args) {
// CSRF protection successful if you reached
// this far.
});
$app->run();
// Start PHP session
session_start();
$app = new \Slim\App();
// Register with container
$container = $app->getContainer();
$container['csrf'] = function ($c) {
return new \Slim\Csrf\Guard;
};
$app->get('/api/myEndPoint',function ($req, $res, $args) {
$nameKey = $this->csrf->getTokenNameKey();
$valueKey = $this->csrf->getTokenValueKey();
$name = $req->getAttribute($nameKey);
$value = $req->getAttribute($valueKey);
$tokenArray = [
$nameKey => $name,
$valueKey => $value
]
return $response->write(json_encode($tokenArray));
})->addMiddleware($container->get('csrf');
$app->post('/api/myEndPoint',function ($req, $res, $args) {
//Do my Things Securely!
})->addMiddleware($container->get('csrf'));
$app->run();
By default, Slim\Csrf\Guard
will return a Response with a 400 status code and
a simple plain text error message.
To override this, provide a callable as the third parameter to the constructor
or via setFailureCallable()
. This callable has the same signature as
middleware: function($request, $response, $next)
and must return a Response.
For example:
$container['csrf'] = function ($c) {
$guard = new \Slim\Csrf\Guard();
$guard->setFailureCallable(function ($request, $response, $next) {
$request = $request->withAttribute("csrf_status", false);
return $next($request, $response);
});
return $guard;
};
In this example, an attribute is set on the request object that can then be checked in subsequent middleware or the route callable using:
if (false === $request->getAttribute('csrf_status')) {
// display suitable error here
} else {
// successfully passed CSRF check
}
$ phpunit
Please see CONTRIBUTING for details.
If you discover any security related issues, please email security@slimframework.com instead of using the issue tracker.
The MIT License (MIT). Please see License File for more information.