PrivateBin/lib/zerobin.php

465 lines
15 KiB
PHP

<?php
/**
* ZeroBin
*
* a zero-knowledge paste bin
*
* @link http://sebsauvage.net/wiki/doku.php?id=php:zerobin
* @copyright 2012 Sébastien SAUVAGE (sebsauvage.net)
* @license http://www.opensource.org/licenses/zlib-license.php The zlib/libpng License
* @version 0.21.1
*/
/**
* zerobin
*
* Controller, puts it all together.
*/
class zerobin
{
/**
* version
*
* @const string
*/
const VERSION = '0.21.1';
/**
* 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 = '';
/**
* formatter
*
* @access private
* @var string
*/
private $_formatter = 'plaintext';
/**
* 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;
/**
* constructor
*
* initializes and runs ZeroBin
*
* @access public
* @return void
*/
public function __construct()
{
if (version_compare(PHP_VERSION, '5.2.6') < 0)
{
throw new Exception(i18n::_('ZeroBin requires php 5.2.6 or above to work. Sorry.'), 1);
}
// in case stupid admin has left magic_quotes enabled in php.ini
if (get_magic_quotes_gpc())
{
$_POST = array_map('filter::stripslashes_deep', $_POST);
$_GET = array_map('filter::stripslashes_deep', $_GET);
$_COOKIE = array_map('filter::stripslashes_deep', $_COOKIE);
}
// load config from ini file
$this->_init();
// create new paste or comment
if (
(array_key_exists('data', $_POST) && !empty($_POST['data'])) ||
(array_key_exists('attachment', $_POST) && !empty($_POST['attachment']))
)
{
$this->_create();
}
// delete an existing paste
elseif (!empty($_GET['deletetoken']) && !empty($_GET['pasteid']))
{
$this->_delete($_GET['pasteid'], $_GET['deletetoken']);
}
// display an existing paste
elseif (!empty($_SERVER['QUERY_STRING']))
{
$this->_read($_SERVER['QUERY_STRING']);
}
// output JSON or HTML
if (strlen($this->_json))
{
header('Content-type: application/json');
echo $this->_json;
}
else
{
$this->_view();
}
}
/**
* initialize zerobin
*
* @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);
}
/**
* 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()
{
$error = false;
// Ensure last paste from visitors IP address was more than configured amount of seconds ago.
trafficlimiter::setConfiguration($this->_conf);
if (!trafficlimiter::canPass()) return $this->_return_message(
1, i18n::_(
'Please wait %d seconds between each post.',
$this->_conf->getKey('limit', 'traffic')
)
);
$has_attachment = array_key_exists('attachment', $_POST);
$has_attachmentname = $has_attachment && array_key_exists('attachmentname', $_POST) && !empty($_POST['attachmentname']);
$data = array_key_exists('data', $_POST) ? $_POST['data'] : '';
$attachment = $has_attachment ? $_POST['attachment'] : '';
$attachmentname = $has_attachmentname ? $_POST['attachmentname'] : '';
// Ensure content is not too big.
$sizelimit = $this->_conf->getKey('sizelimit');
if (
strlen($data) + strlen($attachment) + strlen($attachmentname) > $sizelimit
) return $this->_return_message(
1,
i18n::_(
'Paste is limited to %s of encrypted data.',
filter::size_humanreadable($sizelimit)
)
);
// The user posts a comment.
if (
array_key_exists('parentid', $_POST) && !empty($_POST['parentid']) &&
array_key_exists('pasteid', $_POST) && !empty($_POST['pasteid'])
)
{
$paste = $this->_model->getPaste($_POST['pasteid']);
if ($paste->exists()) {
try {
$comment = $paste->getComment($_POST['parentid']);
if (array_key_exists('nickname', $_POST) && !empty($_POST['nickname'])
) $comment->setNickname($_POST['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
{
$paste = $this->_model->getPaste();
try {
if ($has_attachment)
{
$paste->setAttachment($attachment);
if ($has_attachmentname)
$paste->setAttachmentName($attachmentname);
}
if (array_key_exists('expire', $_POST) && !empty($_POST['expire'])
) $paste->setExpiration($_POST['expire']);
if (array_key_exists('burnafterreading', $_POST) && !empty($_POST['burnafterreading'])
) $paste->setBurnafterreading($_POST['burnafterreading']);
if (array_key_exists('opendiscussion', $_POST) && !empty($_POST['opendiscussion'])
) $paste->setOpendiscussion($_POST['opendiscussion']);
if (array_key_exists('formatter', $_POST) && !empty($_POST['formatter'])
) $paste->setFormatter($_POST['formatter']);
$paste->setData($data);
$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
{
$this->_return_message(1, 'Paste is not of burn-after-reading type.');
}
}
else
{
// Make sure the token is valid.
serversalt::setPath($this->_conf->getKey('dir', 'traffic'));
if (filter::slow_equals($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)
{
$isJson = false;
if (($pos = strpos($dataid, '&json')) !== false) {
$isJson = true;
$dataid = substr($dataid, 0, $pos);
}
try {
$paste = $this->_model->getPaste($dataid);
if ($paste->exists())
{
// The paste itself is the first in the list of encrypted messages.
$messages = array_merge(
array($paste->get()),
$paste->getComments()
);
$this->_data = json_encode($messages);
}
else
{
$this->_error = self::GENERIC_ERROR;
}
} catch (Exception $e) {
$this->_error = $e->getMessage();
return;
}
if ($isJson)
{
if (strlen($this->_error))
{
$this->_return_message(1, $this->_error);
}
else
{
$this->_return_message(0, $dataid, array('messages' => $messages));
}
}
}
/**
* Display ZeroBin 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, must-revalidate');
header('Pragma: no-cache');
header('Expires: ' . $time);
header('Last-Modified: ' . $time);
header('Vary: Accept');
// label all the expiration options
$expire = array();
foreach ($this->_conf->getSection('expire_options') as $time => $seconds)
{
$expire[$time] = ($seconds == 0) ? i18n::_(ucfirst($time)): filter::time_humanreadable($time);
}
// translate all the formatter options
$formatters = array_map(array('i18n', 'translate'), $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 RainTPL;
$page::$path_replace = false;
// we escape it here because ENT_NOQUOTES can't be used in RainTPL templates
$page->assign('CIPHERDATA', htmlspecialchars($this->_data, ENT_NOQUOTES));
$page->assign('ERROR', i18n::_($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('BASE64JSVERSION', $this->_conf->getKey('base64version'));
$page->assign('LANGUAGESELECTION', $languageselection);
$page->assign('LANGUAGES', i18n::getLanguageLabels(i18n::getAvailableLanguages()));
$page->assign('EXPIRE', $expire);
$page->assign('EXPIREDEFAULT', $this->_conf->getKey('default', 'expire'));
$page->draw($this->_conf->getKey('template'));
}
/**
* return JSON encoded message and exit
*
* @access private
* @param bool $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 += $other;
$this->_json = json_encode($result);
}
}