paste.chapril.org-privatebin/lib/Data/Filesystem.php
Felix J. Ogris 9a61e8fd48 started script for storage backend migrations
todo: GCS

added GCS, no GLOBALS, two methods for saving pastes and comments

use GLOBALS for verbosity again

added getAllPastes() to all storage providers

moved to bin, added --delete options, make use of $store->getAllPastes()

added --delete-* options to help

longopts without -- *sigh*

fixed arguments

drop singleton behaviour to allow multiple backends of the same type simultaneously

remove singleton from Model, collapse loop in migrate.php

comments is not indexed

tests without data singleton

fix

exit if scandir() fails

extended meta doc
2022-11-01 16:02:17 +01:00

598 lines
18 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 1.4.0
*/
namespace PrivateBin\Data;
use Exception;
use PrivateBin\Json;
/**
* Filesystem
*
* Model for filesystem data access, implemented as a singleton.
*/
class Filesystem extends AbstractData
{
/**
* first line in paste or comment files, to protect their contents from browsing exposed data directories
*
* @const string
*/
const PROTECTION_LINE = '<?php http_response_code(403); /*';
/**
* line in generated .htaccess files, to protect exposed directories from being browsable on apache web servers
*
* @const string
*/
const HTACCESS_LINE = 'Require all denied';
/**
* path in which to persist something
*
* @access private
* @var string
*/
private $_path = 'data';
/**
* instantiates a new Filesystem data backend
*
* @access public
* @param array $options
* @return
*/
public function __construct(array $options)
{
// if given update the data directory
if (
is_array($options) &&
array_key_exists('dir', $options)
) {
$this->_path = $options['dir'];
}
}
/**
* Create a paste.
*
* @access public
* @param string $pasteid
* @param array $paste
* @return bool
*/
public function create($pasteid, array $paste)
{
$storagedir = $this->_dataid2path($pasteid);
$file = $storagedir . $pasteid . '.php';
if (is_file($file)) {
return false;
}
if (!is_dir($storagedir)) {
mkdir($storagedir, 0700, true);
}
return $this->_store($file, $paste);
}
/**
* Read a paste.
*
* @access public
* @param string $pasteid
* @return array|false
*/
public function read($pasteid)
{
if (
!$this->exists($pasteid) ||
!$paste = $this->_get($this->_dataid2path($pasteid) . $pasteid . '.php')
) {
return false;
}
return self::upgradePreV1Format($paste);
}
/**
* Delete a paste and its discussion.
*
* @access public
* @param string $pasteid
*/
public function delete($pasteid)
{
$pastedir = $this->_dataid2path($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 = $this->_dataid2discussionpath($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 = $this->_dataid2path($pasteid) . $pasteid;
$pastePath = $basePath . '.php';
// convert to PHP protected files if needed
if (is_readable($basePath)) {
$this->_prependRename($basePath, $pastePath);
// convert comments, too
$discdir = $this->_dataid2discussionpath($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';
$this->_prependRename($discdir . $filename, $commentFilename);
}
}
$dir->close();
}
}
return is_readable($pastePath);
}
/**
* Create a comment in a paste.
*
* @access public
* @param string $pasteid
* @param string $parentid
* @param string $commentid
* @param array $comment
* @return bool
*/
public function createComment($pasteid, $parentid, $commentid, array $comment)
{
$storagedir = $this->_dataid2discussionpath($pasteid);
$file = $storagedir . $pasteid . '.' . $commentid . '.' . $parentid . '.php';
if (is_file($file)) {
return false;
}
if (!is_dir($storagedir)) {
mkdir($storagedir, 0700, true);
}
return $this->_store($file, $comment);
}
/**
* Read all comments of paste.
*
* @access public
* @param string $pasteid
* @return array
*/
public function readComments($pasteid)
{
$comments = array();
$discdir = $this->_dataid2discussionpath($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 = $this->_get($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']['created']);
$comments[$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(
$this->_dataid2discussionpath($pasteid) .
$pasteid . '.' . $commentid . '.' . $parentid . '.php'
);
}
/**
* Save a value.
*
* @access public
* @param string $value
* @param string $namespace
* @param string $key
* @return bool
*/
public function setValue($value, $namespace, $key = '')
{
switch ($namespace) {
case 'purge_limiter':
return $this->_storeString(
$this->_path . DIRECTORY_SEPARATOR . 'purge_limiter.php',
'<?php' . PHP_EOL . '$GLOBALS[\'purge_limiter\'] = ' . $value . ';'
);
case 'salt':
return $this->_storeString(
$this->_path . DIRECTORY_SEPARATOR . 'salt.php',
'<?php # |' . $value . '|'
);
case 'traffic_limiter':
$this->_last_cache[$key] = $value;
return $this->_storeString(
$this->_path . DIRECTORY_SEPARATOR . 'traffic_limiter.php',
'<?php' . PHP_EOL . '$GLOBALS[\'traffic_limiter\'] = ' . var_export($this->_last_cache, true) . ';'
);
}
return false;
}
/**
* Load a value.
*
* @access public
* @param string $namespace
* @param string $key
* @return string
*/
public function getValue($namespace, $key = '')
{
switch ($namespace) {
case 'purge_limiter':
$file = $this->_path . DIRECTORY_SEPARATOR . 'purge_limiter.php';
if (is_readable($file)) {
require $file;
return $GLOBALS['purge_limiter'];
}
break;
case 'salt':
$file = $this->_path . DIRECTORY_SEPARATOR . 'salt.php';
if (is_readable($file)) {
$items = explode('|', file_get_contents($file));
if (is_array($items) && count($items) == 3) {
return $items[1];
}
}
break;
case 'traffic_limiter':
$file = $this->_path . DIRECTORY_SEPARATOR . 'traffic_limiter.php';
if (is_readable($file)) {
require $file;
$this->_last_cache = $GLOBALS['traffic_limiter'];
if (array_key_exists($key, $this->_last_cache)) {
return $this->_last_cache[$key];
}
}
break;
}
return '';
}
/**
* get the data
*
* @access public
* @param string $filename
* @return array|false $data
*/
private function _get($filename)
{
return Json::decode(
substr(
file_get_contents($filename),
strlen(self::PROTECTION_LINE . PHP_EOL)
)
);
}
/**
* 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();
$firstLevel = array_filter(
scandir($this->_path),
'PrivateBin\Data\Filesystem::_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);
$secondLevel = array_filter(
scandir($this->_path . DIRECTORY_SEPARATOR . $firstLevel[$firstKey]),
'PrivateBin\Data\Filesystem::_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 = $this->_path . DIRECTORY_SEPARATOR .
$firstLevel[$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 (
array_key_exists('expire_date', $data['meta']) &&
$data['meta']['expire_date'] < time()
) {
$pastes[] = $pasteid;
if (count($pastes) >= $batchsize) {
break;
}
}
}
}
}
return $pastes;
}
/**
* @inheritDoc
*/
public function getAllPastes()
{
$pastes = array();
$subdirs = scandir($this->_path);
if ($subdirs === false) {
dieerr("Unable to list directory " . $this->_path);
}
$subdirs = preg_grep("/^[^.].$/", $subdirs);
foreach ($subdirs as $subdir) {
$subpath = $this->_path . DIRECTORY_SEPARATOR . $subdir;
$subsubdirs = scandir($subpath);
if ($subsubdirs === false) {
dieerr("Unable to list directory " . $subpath);
}
$subsubdirs = preg_grep("/^[^.].$/", $subsubdirs);
foreach ($subsubdirs as $subsubdir) {
$subsubpath = $subpath . DIRECTORY_SEPARATOR . $subsubdir;
$files = scandir($subsubpath);
if ($files === false) {
dieerr("Unable to list directory " . $subsubpath);
}
$files = preg_grep("/\.php$/", $files);
foreach ($files as $file) {
if (substr($file, 0, 4) === $subdir . $subsubdir) {
$pastes[] = substr($file, 0, strlen($file) - 4);
}
}
}
}
return $pastes;
}
/**
* 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
* @param string $dataid
* @return string
*/
private function _dataid2path($dataid)
{
return $this->_path . DIRECTORY_SEPARATOR .
substr($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
* @param string $dataid
* @return string
*/
private function _dataid2discussionpath($dataid)
{
return $this->_dataid2path($dataid) . $dataid .
'.discussion' . DIRECTORY_SEPARATOR;
}
/**
* Check that the given element is a valid first level directory.
*
* @access private
* @param string $element
* @return bool
*/
private function _isFirstLevelDir($element)
{
return $this->_isSecondLevelDir($element) &&
is_dir($this->_path . DIRECTORY_SEPARATOR . $element);
}
/**
* Check that the given element is a valid second level directory.
*
* @access private
* @param string $element
* @return bool
*/
private function _isSecondLevelDir($element)
{
return (bool) preg_match('/^[a-f0-9]{2}$/', $element);
}
/**
* store the data
*
* @access public
* @param string $filename
* @param array $data
* @return bool
*/
private function _store($filename, array $data)
{
try {
return $this->_storeString(
$filename,
self::PROTECTION_LINE . PHP_EOL . Json::encode($data)
);
} catch (Exception $e) {
return false;
}
}
/**
* store a string
*
* @access public
* @param string $filename
* @param string $data
* @return bool
*/
private function _storeString($filename, $data)
{
// Create storage directory if it does not exist.
if (!is_dir($this->_path)) {
if (!@mkdir($this->_path, 0700)) {
return false;
}
}
$file = $this->_path . DIRECTORY_SEPARATOR . '.htaccess';
if (!is_file($file)) {
$writtenBytes = 0;
if ($fileCreated = @touch($file)) {
$writtenBytes = @file_put_contents(
$file,
self::HTACCESS_LINE . PHP_EOL,
LOCK_EX
);
}
if (
$fileCreated === false ||
$writtenBytes === false ||
$writtenBytes < strlen(self::HTACCESS_LINE . PHP_EOL)
) {
return false;
}
}
$fileCreated = true;
$writtenBytes = 0;
if (!is_file($filename)) {
$fileCreated = @touch($filename);
}
if ($fileCreated) {
$writtenBytes = @file_put_contents($filename, $data, LOCK_EX);
}
if ($fileCreated === false || $writtenBytes === false || $writtenBytes < strlen($data)) {
return false;
}
@chmod($filename, 0640); // protect file from access by other users on the host
return true;
}
/**
* rename a file, prepending the protection line at the beginning
*
* @access public
* @param string $srcFile
* @param string $destFile
* @return void
*/
private function _prependRename($srcFile, $destFile)
{
// don't overwrite already converted file
if (!is_readable($destFile)) {
$handle = fopen($srcFile, 'r', false, stream_context_create());
file_put_contents($destFile, self::PROTECTION_LINE . PHP_EOL);
file_put_contents($destFile, $handle, FILE_APPEND);
fclose($handle);
}
unlink($srcFile);
}
}