paste.chapril.org-privatebin/lib/Data/Filesystem.php

440 lines
13 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 1.1.1
*/
namespace PrivateBin\Data;
use PrivateBin\Json;
use PrivateBin\Model\Paste;
/**
* Filesystem
*
* Model for filesystem data access, implemented as a singleton.
*/
class Filesystem extends AbstractData
{
/**
* First line in JSON files, to hide contents
*
* @const string
*/
const PROTECTION_LINE = '<?php http_response_code(403); /*';
/**
* directory where data is stored
*
* @access private
* @static
* @var string
*/
private static $_dir = 'data/';
/**
* get instance of singleton
*
* @access public
* @static
* @param array $options
* @return Filesystem
*/
public static function getInstance($options = null)
{
// if given update the data directory
if (
is_array($options) &&
array_key_exists('dir', $options)
) {
self::$_dir = $options['dir'] . DIRECTORY_SEPARATOR;
}
// if needed initialize the singleton
if (!(self::$_instance instanceof self)) {
self::$_instance = new self;
self::_init();
}
return self::$_instance;
}
/**
* Create a paste.
*
* @access public
* @param string $pasteid
* @param array $paste
* @throws Exception
* @return bool
*/
public function create($pasteid, $paste)
{
$storagedir = self::_dataid2path($pasteid);
if (is_file($storagedir . $pasteid . '.php')) {
return false;
}
if (!is_dir($storagedir)) {
mkdir($storagedir, 0700, true);
}
return (bool) file_put_contents($storagedir . $pasteid . '.php', self::PROTECTION_LINE . PHP_EOL . Json::encode($paste));
}
/**
* Read a paste.
*
* @access public
* @param string $pasteid
* @return stdClass|false
*/
public function read($pasteid)
{
if (!$this->exists($pasteid)) {
return false;
}
$paste = self::_decodeFile(self::_dataid2path($pasteid) . $pasteid . '.php');
if (property_exists($paste->meta, 'attachment')) {
$paste->attachment = $paste->meta->attachment;
unset($paste->meta->attachment);
if (property_exists($paste->meta, 'attachmentname')) {
$paste->attachmentname = $paste->meta->attachmentname;
unset($paste->meta->attachmentname);
}
}
return $paste;
}
/**
* Delete a paste and its discussion.
*
* @access public
* @param string $pasteid
* @return void
*/
public function delete($pasteid)
{
$pastedir = self::_dataid2path($pasteid);
if (is_dir($pastedir)) {
// Delete the paste itself.
if (is_file($pastedir . $pasteid . '.php')) {
unlink($pastedir . $pasteid . '.php');
}
// Delete discussion if it exists.
$discdir = self::_dataid2discussionpath($pasteid);
if (is_dir($discdir)) {
// Delete all files in discussion directory
$dir = dir($discdir);
while (false !== ($filename = $dir->read())) {
if (is_file($discdir . $filename)) {
unlink($discdir . $filename);
}
}
$dir->close();
rmdir($discdir);
}
}
}
/**
* Test if a paste exists.
*
* @access public
* @param string $pasteid
* @return bool
*/
public function exists($pasteid)
{
$basePath = self::_dataid2path($pasteid) . $pasteid;
$pastePath = $basePath . '.php';
// convert to PHP protected files if needed
if (is_readable($basePath)) {
$context = stream_context_create();
// don't overwrite already converted file
if (!is_file($pastePath)) {
$handle = fopen($basePath, 'r', false, $context);
file_put_contents($pastePath, self::PROTECTION_LINE . PHP_EOL);
file_put_contents($pastePath, $handle, FILE_APPEND);
fclose($handle);
}
unlink($basePath);
// convert comments, too
$discdir = self::_dataid2discussionpath($pasteid);
if (is_dir($discdir)) {
$dir = dir($discdir);
while (false !== ($filename = $dir->read())) {
if (substr($filename, -4) !== '.php' && strlen($filename) >= 16) {
$commentFilename = $discdir . $filename . '.php';
// don't overwrite already converted file
if (!is_file($commentFilename)) {
$handle = fopen($discdir . $filename, 'r', false, $context);
file_put_contents($commentFilename, self::PROTECTION_LINE . PHP_EOL);
file_put_contents($commentFilename, $handle, FILE_APPEND);
fclose($handle);
}
unlink($discdir . $filename);
}
}
$dir->close();
}
}
return is_readable($pastePath);
}
/**
* Create a comment in a paste.
*
* @access public
* @param string $pasteid
* @param string $parentid
* @param string $commentid
* @param array $comment
* @throws Exception
* @return bool
*/
public function createComment($pasteid, $parentid, $commentid, $comment)
{
$storagedir = self::_dataid2discussionpath($pasteid);
$filename = $pasteid . '.' . $commentid . '.' . $parentid . '.php';
if (is_file($storagedir . $filename)) {
return false;
}
if (!is_dir($storagedir)) {
mkdir($storagedir, 0700, true);
}
return (bool) file_put_contents($storagedir . $filename, self::PROTECTION_LINE . PHP_EOL . Json::encode($comment));
}
/**
* Read all comments of paste.
*
* @access public
* @param string $pasteid
* @return array
*/
public function readComments($pasteid)
{
$comments = array();
$discdir = self::_dataid2discussionpath($pasteid);
if (is_dir($discdir)) {
$dir = dir($discdir);
while (false !== ($filename = $dir->read())) {
// Filename is in the form pasteid.commentid.parentid.php:
// - pasteid is the paste this reply belongs to.
// - commentid is the comment identifier itself.
// - parentid is the comment this comment replies to (It can be pasteid)
if (is_file($discdir . $filename)) {
$comment = self::_decodeFile($discdir . $filename);
$items = explode('.', $filename);
// Add some meta information not contained in file.
$comment->id = $items[1];
$comment->parentid = $items[2];
// Store in array
$key = $this->getOpenSlot($comments, (int) $comment->meta->postdate);
$comments[$key] = $comment;
}
}
$dir->close();
// Sort comments by date, oldest first.
ksort($comments);
}
return $comments;
}
/**
* Test if a comment exists.
*
* @access public
* @param string $pasteid
* @param string $parentid
* @param string $commentid
* @return bool
*/
public function existsComment($pasteid, $parentid, $commentid)
{
return is_file(
self::_dataid2discussionpath($pasteid) .
$pasteid . '.' . $commentid . '.' . $parentid . '.php'
);
}
/**
* Returns up to batch size number of paste ids that have expired
*
* @access private
* @param int $batchsize
* @return array
*/
protected function _getExpiredPastes($batchsize)
{
$pastes = array();
$firstLevel = array_filter(
scandir(self::$_dir),
'self::_isFirstLevelDir'
);
if (count($firstLevel) > 0) {
// try at most 10 times the $batchsize pastes before giving up
for ($i = 0, $max = $batchsize * 10; $i < $max; ++$i) {
$firstKey = array_rand($firstLevel);
$secondLevel = array_filter(
scandir(self::$_dir . $firstLevel[$firstKey]),
'self::_isSecondLevelDir'
);
// skip this folder in the next checks if it is empty
if (count($secondLevel) == 0) {
unset($firstLevel[$firstKey]);
continue;
}
$secondKey = array_rand($secondLevel);
$path = self::$_dir . $firstLevel[$firstKey] .
DIRECTORY_SEPARATOR . $secondLevel[$secondKey];
if (!is_dir($path)) {
continue;
}
$thirdLevel = array_filter(
array_map(
function ($filename) {
return strlen($filename) >= 20 ?
substr($filename, 0, -4) :
$filename;
},
scandir($path)
),
'PrivateBin\\Model\\Paste::isValidId'
);
if (count($thirdLevel) == 0) {
continue;
}
$thirdKey = array_rand($thirdLevel);
$pasteid = $thirdLevel[$thirdKey];
if (in_array($pasteid, $pastes)) {
continue;
}
if ($this->exists($pasteid)) {
$data = $this->read($pasteid);
if (
property_exists($data->meta, 'expire_date') &&
$data->meta->expire_date < time()
) {
$pastes[] = $pasteid;
if (count($pastes) >= $batchsize) {
break;
}
}
}
}
}
return $pastes;
}
/**
* initialize privatebin
*
* @access private
* @static
* @return void
*/
private static function _init()
{
// Create storage directory if it does not exist.
if (!is_dir(self::$_dir)) {
mkdir(self::$_dir, 0700);
}
// Create .htaccess file if it does not exist.
if (!is_file(self::$_dir . '.htaccess')) {
file_put_contents(
self::$_dir . '.htaccess',
'Allow from none' . PHP_EOL .
'Deny from all' . PHP_EOL
);
}
}
/**
* Convert paste id to storage path.
*
* The idea is to creates subdirectories in order to limit the number of files per directory.
* (A high number of files in a single directory can slow things down.)
* eg. "f468483c313401e8" will be stored in "data/f4/68/f468483c313401e8"
* High-trafic websites may want to deepen the directory structure (like Squid does).
*
* eg. input 'e3570978f9e4aa90' --> output 'data/e3/57/'
*
* @access private
* @static
* @param string $dataid
* @return string
*/
private static function _dataid2path($dataid)
{
return self::$_dir . substr($dataid, 0, 2) . DIRECTORY_SEPARATOR .
substr($dataid, 2, 2) . DIRECTORY_SEPARATOR;
}
/**
* Convert paste id to discussion storage path.
*
* eg. input 'e3570978f9e4aa90' --> output 'data/e3/57/e3570978f9e4aa90.discussion/'
*
* @access private
* @static
* @param string $dataid
* @return string
*/
private static function _dataid2discussionpath($dataid)
{
return self::_dataid2path($dataid) . $dataid .
'.discussion' . DIRECTORY_SEPARATOR;
}
/**
* Check that the given element is a valid first level directory.
*
* @access private
* @static
* @param string $element
* @return bool
*/
private static function _isFirstLevelDir($element)
{
return self::_isSecondLevelDir($element) &&
is_dir(self::$_dir . DIRECTORY_SEPARATOR . $element);
}
/**
* Check that the given element is a valid second level directory.
*
* @access private
* @static
* @param string $element
* @return bool
*/
private static function _isSecondLevelDir($element)
{
return (bool) preg_match('/^[a-f0-9]{2}$/', $element);
}
/**
* Decodes a paste or comment file.
*
* @access private
* @static
* @param string $file
* @return array
*/
private static function _decodeFile($file)
{
return json_decode(substr(file_get_contents($file), strlen(self::PROTECTION_LINE . PHP_EOL)));
}
}