PrivateBin/lib/PrivateBin.php
2016-12-12 18:50:00 +01:00

511 lines
17 KiB
PHP

<?php
/**
* PrivateBin
*
* a zero-knowledge paste bin
*
* @link https://github.com/PrivateBin/PrivateBin
* @copyright 2012 Sébastien SAUVAGE (sebsauvage.net)
* @license https://www.opensource.org/licenses/zlib-license.php The zlib/libpng License
* @version 1.0
*/
namespace PrivateBin;
use Exception;
use PrivateBin\Persistence\ServerSalt;
use PrivateBin\Persistence\TrafficLimiter;
/**
* PrivateBin
*
* Controller, puts it all together.
*/
class PrivateBin
{
/**
* version
*
* @const string
*/
const VERSION = '1.0';
/**
* show the same error message if the paste expired or does not exist
*
* @const string
*/
const GENERIC_ERROR = 'Paste does not exist, has expired or has been deleted.';
/**
* configuration
*
* @access private
* @var Configuration
*/
private $_conf;
/**
* data
*
* @access private
* @var string
*/
private $_data = '';
/**
* does the paste expire
*
* @access private
* @var bool
*/
private $_doesExpire = false;
/**
* error message
*
* @access private
* @var string
*/
private $_error = '';
/**
* status message
*
* @access private
* @var string
*/
private $_status = '';
/**
* JSON message
*
* @access private
* @var string
*/
private $_json = '';
/**
* Factory of instance models
*
* @access private
* @var model
*/
private $_model;
/**
* request
*
* @access private
* @var request
*/
private $_request;
/**
* URL base
*
* @access private
* @var string
*/
private $_urlBase;
/**
* constructor
*
* initializes and runs PrivateBin
*
* @access public
* @throws Exception
* @return void
*/
public function __construct()
{
if (version_compare(PHP_VERSION, '5.3.0') < 0) {
throw new Exception(I18n::_('PrivateBin requires php 5.3.0 or above to work. Sorry.'), 1);
}
if (strlen(PATH) < 0 && substr(PATH, -1) !== DIRECTORY_SEPARATOR) {
throw new Exception(I18n::_('PrivateBin requires the PATH to end in a "%s". Please update the PATH in your index.php.', DIRECTORY_SEPARATOR), 5);
}
// load config from ini file, initialize required classes
$this->_init();
switch ($this->_request->getOperation()) {
case 'create':
$this->_create();
break;
case 'delete':
$this->_delete(
$this->_request->getParam('pasteid'),
$this->_request->getParam('deletetoken')
);
break;
case 'read':
$this->_read($this->_request->getParam('pasteid'));
break;
case 'jsonld':
$this->_jsonld($this->_request->getParam('jsonld'));
return;
}
// output JSON or HTML
if ($this->_request->isJsonApiCall()) {
header('Content-type: ' . Request::MIME_JSON);
header('Access-Control-Allow-Origin: *');
header('Access-Control-Allow-Methods: GET, POST, PUT, DELETE');
header('Access-Control-Allow-Headers: X-Requested-With, Content-Type');
echo $this->_json;
} else {
$this->_view();
}
}
/**
* initialize privatebin
*
* @access private
* @return void
*/
private function _init()
{
foreach (array('cfg', 'lib') as $dir) {
if (!is_file(PATH . $dir . DIRECTORY_SEPARATOR . '.htaccess')) {
file_put_contents(
PATH . $dir . DIRECTORY_SEPARATOR . '.htaccess',
'Allow from none' . PHP_EOL .
'Deny from all' . PHP_EOL,
LOCK_EX
);
}
}
$this->_conf = new Configuration;
$this->_model = new Model($this->_conf);
$this->_request = new Request;
$this->_urlBase = array_key_exists('REQUEST_URI', $_SERVER) ?
htmlspecialchars($_SERVER['REQUEST_URI']) : '/';
ServerSalt::setPath($this->_conf->getKey('dir', 'traffic'));
// set default language
$lang = $this->_conf->getKey('languagedefault');
I18n::setLanguageFallback($lang);
// force default language, if language selection is disabled and a default is set
if (!$this->_conf->getKey('languageselection') && strlen($lang) == 2) {
$_COOKIE['lang'] = $lang;
setcookie('lang', $lang);
}
}
/**
* Store new paste or comment
*
* POST contains one or both:
* data = json encoded SJCL encrypted text (containing keys: iv,v,iter,ks,ts,mode,adata,cipher,salt,ct)
* attachment = json encoded SJCL encrypted text (containing keys: iv,v,iter,ks,ts,mode,adata,cipher,salt,ct)
*
* All optional data will go to meta information:
* expire (optional) = expiration delay (never,5min,10min,1hour,1day,1week,1month,1year,burn) (default:never)
* formatter (optional) = format to display the paste as (plaintext,syntaxhighlighting,markdown) (default:syntaxhighlighting)
* burnafterreading (optional) = if this paste may only viewed once ? (0/1) (default:0)
* opendiscusssion (optional) = is the discussion allowed on this paste ? (0/1) (default:0)
* attachmentname = json encoded SJCL encrypted text (containing keys: iv,v,iter,ks,ts,mode,adata,cipher,salt,ct)
* nickname (optional) = in discussion, encoded SJCL encrypted text nickname of author of comment (containing keys: iv,v,iter,ks,ts,mode,adata,cipher,salt,ct)
* parentid (optional) = in discussion, which comment this comment replies to.
* pasteid (optional) = in discussion, which paste this comment belongs to.
*
* @access private
* @return string
*/
private function _create()
{
// Ensure last paste from visitors IP address was more than configured amount of seconds ago.
TrafficLimiter::setConfiguration($this->_conf);
if (!TrafficLimiter::canPass()) {
return $this->_return_message(
1, I18n::_(
'Please wait %d seconds between each post.',
$this->_conf->getKey('limit', 'traffic')
)
);
}
$data = $this->_request->getParam('data');
$attachment = $this->_request->getParam('attachment');
$attachmentname = $this->_request->getParam('attachmentname');
// Ensure content is not too big.
$sizelimit = $this->_conf->getKey('sizelimit');
if (
strlen($data) + strlen($attachment) + strlen($attachmentname) > $sizelimit
) {
return $this->_return_message(
1,
I18n::_(
'Paste is limited to %s of encrypted data.',
Filter::formatHumanReadableSize($sizelimit)
)
);
}
// Ensure attachment did not get lost due to webserver limits or Suhosin
if (strlen($attachmentname) > 0 && strlen($attachment) == 0) {
return $this->_return_message(1, 'Attachment missing in data received by server. Please check your webserver or suhosin configuration for maximum POST parameter limitations.');
}
// The user posts a comment.
$pasteid = $this->_request->getParam('pasteid');
$parentid = $this->_request->getParam('parentid');
if (!empty($pasteid) && !empty($parentid)) {
$paste = $this->_model->getPaste($pasteid);
if ($paste->exists()) {
try {
$comment = $paste->getComment($parentid);
$nickname = $this->_request->getParam('nickname');
if (!empty($nickname)) {
$comment->setNickname($nickname);
}
$comment->setData($data);
$comment->store();
} catch (Exception $e) {
return $this->_return_message(1, $e->getMessage());
}
$this->_return_message(0, $comment->getId());
} else {
$this->_return_message(1, 'Invalid data.');
}
}
// The user posts a standard paste.
else {
$this->_model->purge();
$paste = $this->_model->getPaste();
try {
$paste->setData($data);
if (!empty($attachment)) {
$paste->setAttachment($attachment);
if (!empty($attachmentname)) {
$paste->setAttachmentName($attachmentname);
}
}
$expire = $this->_request->getParam('expire');
if (!empty($expire)) {
$paste->setExpiration($expire);
}
$burnafterreading = $this->_request->getParam('burnafterreading');
if (!empty($burnafterreading)) {
$paste->setBurnafterreading($burnafterreading);
}
$opendiscussion = $this->_request->getParam('opendiscussion');
if (!empty($opendiscussion)) {
$paste->setOpendiscussion($opendiscussion);
}
$formatter = $this->_request->getParam('formatter');
if (!empty($formatter)) {
$paste->setFormatter($formatter);
}
$paste->store();
} catch (Exception $e) {
return $this->_return_message(1, $e->getMessage());
}
$this->_return_message(0, $paste->getId(), array('deletetoken' => $paste->getDeleteToken()));
}
}
/**
* Delete an existing paste
*
* @access private
* @param string $dataid
* @param string $deletetoken
* @return void
*/
private function _delete($dataid, $deletetoken)
{
try {
$paste = $this->_model->getPaste($dataid);
if ($paste->exists()) {
// accessing this property ensures that the paste would be
// deleted if it has already expired
$burnafterreading = $paste->isBurnafterreading();
if ($deletetoken == 'burnafterreading') {
if ($burnafterreading) {
$paste->delete();
$this->_return_message(0, $dataid);
} else {
$this->_return_message(1, 'Paste is not of burn-after-reading type.');
}
} else {
// Make sure the token is valid.
if (Filter::slowEquals($deletetoken, $paste->getDeleteToken())) {
// Paste exists and deletion token is valid: Delete the paste.
$paste->delete();
$this->_status = 'Paste was properly deleted.';
} else {
$this->_error = 'Wrong deletion token. Paste was not deleted.';
}
}
} else {
$this->_error = self::GENERIC_ERROR;
}
} catch (Exception $e) {
$this->_error = $e->getMessage();
}
}
/**
* Read an existing paste or comment
*
* @access private
* @param string $dataid
* @return void
*/
private function _read($dataid)
{
try {
$paste = $this->_model->getPaste($dataid);
if ($paste->exists()) {
$data = $paste->get();
$this->_doesExpire = property_exists($data, 'meta') && property_exists($data->meta, 'expire_date');
if (property_exists($data->meta, 'salt')) {
unset($data->meta->salt);
}
$this->_data = json_encode($data);
} else {
$this->_error = self::GENERIC_ERROR;
}
} catch (Exception $e) {
$this->_error = $e->getMessage();
}
if ($this->_request->isJsonApiCall()) {
if (strlen($this->_error)) {
$this->_return_message(1, $this->_error);
} else {
$this->_return_message(0, $dataid, json_decode($this->_data, true));
}
}
}
/**
* Display PrivateBin frontend.
*
* @access private
* @return void
*/
private function _view()
{
// set headers to disable caching
$time = gmdate('D, d M Y H:i:s \G\M\T');
header('Cache-Control: no-store, no-cache, no-transform, must-revalidate');
header('Pragma: no-cache');
header('Expires: ' . $time);
header('Last-Modified: ' . $time);
header('Vary: Accept');
header('Content-Security-Policy: ' . $this->_conf->getKey('cspheader'));
header('X-Xss-Protection: 1; mode=block');
header('X-Frame-Options: DENY');
header('X-Content-Type-Options: nosniff');
// label all the expiration options
$expire = array();
foreach ($this->_conf->getSection('expire_options') as $time => $seconds) {
$expire[$time] = ($seconds == 0) ? I18n::_(ucfirst($time)) : Filter::formatHumanReadableTime($time);
}
// translate all the formatter options
$formatters = array_map('PrivateBin\\I18n::_', $this->_conf->getSection('formatter_options'));
// set language cookie if that functionality was enabled
$languageselection = '';
if ($this->_conf->getKey('languageselection')) {
$languageselection = I18n::getLanguage();
setcookie('lang', $languageselection);
}
$page = new View;
$page->assign('CIPHERDATA', $this->_data);
$page->assign('ERROR', I18n::_($this->_error));
$page->assign('STATUS', I18n::_($this->_status));
$page->assign('VERSION', self::VERSION);
$page->assign('DISCUSSION', $this->_conf->getKey('discussion'));
$page->assign('OPENDISCUSSION', $this->_conf->getKey('opendiscussion'));
$page->assign('MARKDOWN', array_key_exists('markdown', $formatters));
$page->assign('SYNTAXHIGHLIGHTING', array_key_exists('syntaxhighlighting', $formatters));
$page->assign('SYNTAXHIGHLIGHTINGTHEME', $this->_conf->getKey('syntaxhighlightingtheme'));
$page->assign('FORMATTER', $formatters);
$page->assign('FORMATTERDEFAULT', $this->_conf->getKey('defaultformatter'));
$page->assign('NOTICE', I18n::_($this->_conf->getKey('notice')));
$page->assign('BURNAFTERREADINGSELECTED', $this->_conf->getKey('burnafterreadingselected'));
$page->assign('PASSWORD', $this->_conf->getKey('password'));
$page->assign('FILEUPLOAD', $this->_conf->getKey('fileupload'));
$page->assign('ZEROBINCOMPATIBILITY', $this->_conf->getKey('zerobincompatibility'));
$page->assign('LANGUAGESELECTION', $languageselection);
$page->assign('LANGUAGES', I18n::getLanguageLabels(I18n::getAvailableLanguages()));
$page->assign('EXPIRE', $expire);
$page->assign('EXPIREDEFAULT', $this->_conf->getKey('default', 'expire'));
$page->assign('EXPIRECLONE', !$this->_doesExpire || ($this->_doesExpire && $this->_conf->getKey('clone', 'expire')));
$page->assign('URLSHORTENER', $this->_conf->getKey('urlshortener'));
$page->draw($this->_conf->getKey('template'));
}
/**
* outputs requested JSON-LD context
*
* @access private
* @param string $type
* @return void
*/
private function _jsonld($type)
{
if (
$type !== 'paste' && $type !== 'comment' &&
$type !== 'pastemeta' && $type !== 'commentmeta'
) {
$type = '';
}
$content = '{}';
$file = PUBLIC_PATH . DIRECTORY_SEPARATOR . 'js' . DIRECTORY_SEPARATOR . $type . '.jsonld';
if (is_readable($file)) {
$content = str_replace(
'?jsonld=',
$this->_urlBase . '?jsonld=',
file_get_contents($file)
);
}
header('Content-type: application/ld+json');
header('Access-Control-Allow-Origin: *');
header('Access-Control-Allow-Methods: GET');
echo $content;
}
/**
* prepares JSON encoded status message
*
* @access private
* @param int $status
* @param string $message
* @param array $other
* @return void
*/
private function _return_message($status, $message, $other = array())
{
$result = array('status' => $status);
if ($status) {
$result['message'] = I18n::_($message);
} else {
$result['id'] = $message;
$result['url'] = $this->_urlBase . '?' . $message;
}
$result += $other;
$this->_json = json_encode($result);
}
}