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Whether the package needs to be updated according to OWASP? #32

@solventt

Description

@solventt

In the documentation you refer to OWASP: now only Synchronizer Token Pattern and Double Submit Cookie are actual there. HMAC Based Token Pattern and Encryption based Token Pattern were removed.

It should be understood that the Double Submit Cookie will require the configuration to use Yiisoft\Cookies\CookieMiddleware.

But maybe you shouldn't add the Double Submit Cookie pattern, because it seems to me that this thing is for rare use.

Steps to update:

1) To remove HMAC Based Token Pattern
2) To add Double Submit Cookie processing logic to the middleware (optional)
3) To write something like DoubleSubmitCsrfToken (optional)
4) To update the documentation

Draft with the Double Submit Cookie pattern :

final class CsrfMiddleware implements MiddlewareInterface
{
...

private bool $sendCookie = false;

...

public function process(ServerRequestInterface $request, RequestHandlerInterface $handler): ResponseInterface
{
    if ($this->token instanceof DoubleSubmitCsrfToken) {
        $cookieValues = $request->getCookieParams();
        $cookieValue = $cookieValues[$this->parameterName] ?? null;
        
        // the setValue() method is needed to validate the value later, if necessary
        // for example, "return hash_equals($this->getValue(), $token);"
        $cookieValue ? $this->token->setValue($cookieValue) : $this->sendCookie = true;
    }

    if (!$this->validateCsrfToken($request)) {
        $response = $this->responseFactory->createResponse(Status::UNPROCESSABLE_ENTITY);
        $response->getBody()->write(Status::TEXTS[Status::UNPROCESSABLE_ENTITY]);
        return $response;
    }

    $response = $handler->handle($request);

    return $this->sendCookie ?
           $this->token->getCsrfCookie($this->parameterName)->addToResponse($response) :
           $response;
}

Why are checks made before the validateCsrfToken method? OWASP requires the cookie to be set the first time the user visits the site: "When a user visits (even before authenticating to prevent login CSRF), the site should generate a (cryptographically strong) pseudorandom value and set it as a cookie on the user's machine separate from the session identifier."

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