icingaweb2/library/Icinga/Web/Form.php

411 lines
11 KiB
PHP

<?php
// {{{ICINGA_LICENSE_HEADER}}}
/**
* Icinga 2 Web - Head for multiple monitoring frontends
* Copyright (C) 2013 Icinga Development Team
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* @copyright 2013 Icinga Development Team <info@icinga.org>
* @author Icinga Development Team <info@icinga.org>
*/
// {{{ICINGA_LICENSE_HEADER}}}
namespace Icinga\Web;
use \Zend_Controller_Request_Abstract;
use \Zend_Form_Element_Submit;
use \Zend_Form_Element_Reset;
use \Zend_View_Interface;
use \Zend_Form;
use Icinga\Exception\ProgrammingError;
use Icinga\Web\Form\InvalidCSRFTokenException;
/**
* Base class for forms providing CSRF protection, confirmation logic and auto submission
*/
abstract class Form extends Zend_Form
{
/**
* The form's request object
* @var Zend_Controller_Request_Abstract
*/
private $request;
/**
* Whether this form should NOT add random generated "challenge" tokens that are associated with the user's current
* session in order to prevent Cross-Site Request Forgery (CSRF). It is the form's responsibility to verify the
* existence and correctness of this token
* @var bool
*/
protected $tokenDisabled = false;
/**
* Name of the CSRF token element (used to create non-colliding hashes)
* @var string
*/
private $tokenElementName = 'CSRFToken';
/**
* Flag to indicate that form is already build
* @var bool
*/
private $created = false;
/**
* Session id used for CSRF token generation
* @var string
*/
private $sessionId;
/**
* Label for submit button
*
* If omitted, no button will be shown
*
* @var string
*/
private $submitLabel;
/**
* Label for cancel button
*
* If omitted, no button will be shown
*
* @var string
*/
private $cancelLabel;
/**
* Getter for the session ID
*
* If the ID has never been set, the ID from session_id() is returned
*
* @return string
* @see session_id()
* @see setSessionId()
*/
public function getSessionId()
{
if (!$this->sessionId) {
$this->sessionId = session_id();
}
return $this->sessionId;
}
/**
* Setter for the session ID
*
* This method should be used for testing purposes only
*
* @param string $sessionId
*/
public function setSessionId($sessionId)
{
$this->sessionId = $sessionId;
}
/**
* Return the HTML element name of the CSRF token field
*
* @return string
*/
public function getTokenElementName()
{
return $this->tokenElementName;
}
/**
* Render the form to HTML
*
* @param Zend_View_Interface $view
* @return string
*/
public function render(Zend_View_Interface $view = null)
{
// Elements must be there to render the form
$this->buildForm();
return parent::render($view);
}
/**
* Add elements to this form (used by extending classes)
*/
abstract protected function create();
/**
* Method called before validation
*/
protected function preValidation(array $data)
{
}
/**
* Setter for the request
*
* @param Zend_Controller_Request_Abstract $request
*/
public function setRequest(Zend_Controller_Request_Abstract $request)
{
$this->request = $request;
}
/**
* Getter for the request
*
* @return Zend_Controller_Request_Abstract
*/
public function getRequest()
{
return $this->request;
}
/**
* Create the form if not done already
*
* Adds all elements to the form
*/
public function buildForm()
{
if ($this->created === false) {
$this->initCsrfToken();
$this->create();
if ($this->submitLabel) {
$this->addSubmitButton();
}
if ($this->cancelLabel) {
$this->addCancelButton();
}
// Empty action if not safe
if (!$this->getAction() && $this->getRequest()) {
$this->setAction($this->getRequest()->getRequestUri());
}
$this->created = true;
}
}
/**
* Setter for the cancel label
*
* @param string $cancelLabel
*/
public function setCancelLabel($cancelLabel)
{
$this->cancelLabel = $cancelLabel;
}
/**
* Add cancel button to form
*/
private function addCancelButton()
{
$cancelLabel = new Zend_Form_Element_Reset(
array(
'name' => 'btn_reset',
'label' => $this->cancelLabel,
'class' => 'btn pull-right'
)
);
$this->addElement($cancelLabel);
}
/**
* Setter for the submit label
*
* @param string $submitLabel
*/
public function setSubmitLabel($submitLabel)
{
$this->submitLabel = $submitLabel;
}
/**
* Add submit button to form
*/
private function addSubmitButton()
{
$submitButton = new Zend_Form_Element_Submit(
array(
'name' => 'btn_submit',
'label' => $this->submitLabel,
'class' => 'btn btn-primary pull-right'
)
);
$this->addElement($submitButton);
}
/**
* Enable automatic form submission on the given elements
*
* Enables automatic submission of this form once the user edits specific elements
*
* @param array $triggerElements The element names which should auto-submit the form
* @throws ProgrammingError When an element is found which does not yet exist
*/
final public function enableAutoSubmit($triggerElements)
{
foreach ($triggerElements as $elementName) {
$element = $this->getElement($elementName);
if ($element !== null) {
$element->setAttrib('onchange', '$(this.form).submit();');
} else {
throw new ProgrammingError(
'You need to add the element "' . $elementName . '" to' .
' the form before automatic submission can be enabled!'
);
}
}
}
/**
* Check whether the form was submitted with a valid request
*
* Ensures that the current request method is POST, that the form was manually submitted and that the data provided
* in the request is valid and gets repopulated in case its invalid.
*
* @return bool
*/
public function isSubmittedAndValid()
{
if ($this->getRequest()->isPost() === false) {
return false;
}
$this->buildForm();
$checkData = $this->getRequest()->getParams();
$this->assertValidCsrfToken($checkData);
$submitted = true;
if ($this->submitLabel) {
$submitted = isset($checkData['btn_submit']);
}
if ($submitted) {
// perform full validation if submitted
$this->preValidation($checkData);
return $this->isValid($checkData);
} else {
// only populate if not submitted
$this->populate($checkData);
return false;
}
}
/**
* Disable CSRF counter measure and remove its field if already added
*
* This method should be used for testing purposes only
*
* @param bool $disabled
* @see tokenDisabled
*/
final public function setTokenDisabled($disabled = true)
{
$this->tokenDisabled = (boolean) $disabled;
if ($disabled === true) {
$this->removeElement($this->tokenElementName);
}
}
/**
* Add CSRF counter measure field to form
*/
final public function initCsrfToken()
{
if ($this->tokenDisabled || $this->getElement($this->tokenElementName)) {
return;
}
$this->addElement(
'hidden',
$this->tokenElementName,
array(
'value' => $this->generateCsrfTokenAsString(),
'decorators' => array('ViewHelper')
)
);
}
/**
* Test the submitted data for a correct CSRF token
*
* @param array $checkData The POST data send by the user
* @throws InvalidCSRFTokenException When CSRF Validation fails
*/
final public function assertValidCsrfToken(array $checkData)
{
if ($this->tokenDisabled) {
return;
}
if (!isset($checkData[$this->tokenElementName])
|| !$this->hasValidCsrfToken($checkData[$this->tokenElementName])
) {
throw new InvalidCSRFTokenException();
}
}
/**
* Check whether the form's CSRF token-field has a valid value
*
* @param string $elementValue Value from the form element
* @return bool
*/
private function hasValidCsrfToken($elementValue)
{
if ($this->getElement($this->tokenElementName) === null) {
return false;
}
if (strpos($elementValue, '|') === false) {
return false;
}
list($seed, $token) = explode('|', $elementValue);
if (!is_numeric($seed)) {
return false;
}
return $token === hash('sha256', $this->getSessionId() . $seed);
}
/**
* Generate a new (seed, token) pair
*
* @return array
*/
final public function generateCsrfToken()
{
$seed = mt_rand();
$hash = hash('sha256', $this->getSessionId() . $seed);
return array($seed, $hash);
}
/**
* Return the string representation of the CSRF seed/token pair
*
* @return string
*/
final public function generateCsrfTokenAsString()
{
list ($seed, $token) = $this->generateCsrfToken($this->getSessionId());
return sprintf('%s|%s', $seed, $token);
}
}