<?php
/**
* S3.php
*
* an S3 compatible data backend for PrivateBin with CEPH/RadosGW in mind
* see https://docs.ceph.com/en/latest/radosgw/s3/php/
* based on lib/Data/GoogleCloudStorage.php from PrivateBin version 1.4.0
*
* @link https://github.com/PrivateBin/PrivateBin
* @copyright 2022 Felix J. Ogris (https://ogris.de/)
* @license https://www.opensource.org/licenses/zlib-license.php The zlib/libpng License
* @version 1.4.1
*
* Installation:
* 1. Make sure you have composer.lock and composer.json in the document root of your PasteBin
* 2. If not, grab a copy from https://github.com/PrivateBin/PrivateBin
* 3. As non-root user, install the AWS SDK for PHP:
* composer require aws/aws-sdk-php
* (On FreeBSD, install devel/php-composer2 prior, e.g.: make -C /usr/ports/devel/php-composer2 install clean)
* 4. In cfg/conf.php, comment out all [model] and [model_options] settings
* 5. Still in cfg/conf.php, add a new [model] section:
* [model]
* class = S3Storage
* 6. Add a new [model_options] as well, e.g. for a Rados gateway as part of your CEPH cluster:
* [model_options]
* region = ""
* version = "2006-03-01"
* endpoint = "https://s3.my-ceph.invalid"
* use_path_style_endpoint = true
* bucket = "my-bucket"
* prefix = "privatebin" (place all PrivateBin data beneath this prefix)
* accesskey = "my-rados-user"
* secretkey = "my-rados-pass"
*/
namespace PrivateBin\Data;
use Aws\S3\Exception\S3Exception;
use Aws\S3\S3Client;
use PrivateBin\Json;
class S3Storage extends AbstractData
{
/**
* S3 client
*
* @access private
* @static
* @var S3Client
*/
private static $_client = null;
/**
* S3 client options
*
* @access private
* @static
* @var array
*/
private static $_options = array();
/**
* S3 bucket
*
* @access private
* @static
* @var string
*/
private static $_bucket = null;
/**
* S3 prefix for all PrivateBin data in this bucket
*
* @access private
* @static
* @var string
*/
private static $_prefix = '';
/**
* returns an S3 data backend.
*
* @access public
* @static
* @param array $options
* @return S3Storage
*/
public static function getInstance(array $options)
{
// if needed initialize the singleton
if (!(self::$_instance instanceof self)) {
self::$_instance = new self;
}
self::$_options = array();
self::$_options['credentials'] = array();
if (is_array($options) && array_key_exists('region', $options)) {
self::$_options['region'] = $options['region'];
}
if (is_array($options) && array_key_exists('version', $options)) {
self::$_options['version'] = $options['version'];
}
if (is_array($options) && array_key_exists('endpoint', $options)) {
self::$_options['endpoint'] = $options['endpoint'];
}
if (is_array($options) && array_key_exists('accesskey', $options)) {
self::$_options['credentials']['key'] = $options['accesskey'];
}
if (is_array($options) && array_key_exists('secretkey', $options)) {
self::$_options['credentials']['secret'] = $options['secretkey'];
}
if (is_array($options) && array_key_exists('use_path_style_endpoint', $options)) {
self::$_options['use_path_style_endpoint'] = filter_var($options['use_path_style_endpoint'], FILTER_VALIDATE_BOOLEAN);
}
if (is_array($options) && array_key_exists('bucket', $options)) {
self::$_bucket = $options['bucket'];
}
if (is_array($options) && array_key_exists('prefix', $options)) {
self::$_prefix = $options['prefix'];
}
if (empty(self::$_client)) {
self::$_client = new S3Client(self::$_options);
}
return self::$_instance;
}
/**
* returns all objects in the given prefix.
*
* @access private
* @param $prefix string with prefix
* @return array all objects in the given prefix
*/
private function _listAllObjects($prefix)
{
$allObjects = array();
$options = array(
'Bucket' => self::$_bucket,
'Prefix' => $prefix,
);
do {
$objectsListResponse = self::$_client->listObjects($options);
$objects = $objectsListResponse['Contents'] ?? array();
foreach ($objects as $object) {
$allObjects[] = $object;
$options['Marker'] = $object['Key'];
}
} while ($objectsListResponse['IsTruncated']);
return $allObjects;
}
/**
* returns the S3 storage object key for $pasteid in self::$_bucket.
*
* @access private
* @param $pasteid string to get the key for
* @return string
*/
private function _getKey($pasteid)
{
if (self::$_prefix != '') {
return self::$_prefix . '/' . $pasteid;
}
return $pasteid;
}
/**
* Uploads the payload in the self::$_bucket under the specified key.
* The entire payload is stored as a JSON document. The metadata is replicated
* as the S3 object's metadata except for the fields attachment, attachmentname
* and salt.
*
* @param $key string to store the payload under
* @param $payload array to store
* @return bool true if successful, otherwise false.
*/
private function _upload($key, $payload)
{
$metadata = array_key_exists('meta', $payload) ? $payload['meta'] : array();
unset($metadata['attachment'], $metadata['attachmentname'], $metadata['salt']);
foreach ($metadata as $k => $v) {
$metadata[$k] = strval($v);
}
try {
self::$_client->putObject(array(
'Bucket' => self::$_bucket,
'Key' => $key,
'Body' => Json::encode($payload),
'ContentType' => 'application/json',
'Metadata' => $metadata,
));
} catch (S3Exception $e) {
error_log('failed to upload ' . $key . ' to ' . self::$_bucket . ', ' .
trim(preg_replace('/\s\s+/', ' ', $e->getMessage())));
return false;
}
return true;
}
/**
* @inheritDoc
*/
public function create($pasteid, array $paste)
{
if ($this->exists($pasteid)) {
return false;
}
return $this->_upload($this->_getKey($pasteid), $paste);
}
/**
* @inheritDoc
*/
public function read($pasteid)
{
try {
$object = self::$_client->getObject(array(
'Bucket' => self::$_bucket,
'Key' => $this->_getKey($pasteid),
));
$data = $object['Body']->getContents();
return Json::decode($data);
} catch (S3Exception $e) {
error_log('failed to read ' . $pasteid . ' from ' . self::$_bucket . ', ' .
trim(preg_replace('/\s\s+/', ' ', $e->getMessage())));
return false;
}
}
/**
* @inheritDoc
*/
public function delete($pasteid)
{
$name = $this->_getKey($pasteid);
try {
$comments = $this->_listAllObjects($name . '/discussion/');
foreach ($comments as $comment) {
try {
self::$_client->deleteObject(array(
'Bucket' => self::$_bucket,
'Key' => $comment['Key'],
));
} catch (S3Exception $e) {
// ignore if already deleted.
}
}
} catch (S3Exception $e) {
// there are no discussions associated with the paste
}
try {
self::$_client->deleteObject(array(
'Bucket' => self::$_bucket,
'Key' => $name,
));
} catch (S3Exception $e) {
// ignore if already deleted
}
}
/**
* @inheritDoc
*/
public function exists($pasteid)
{
return self::$_client->doesObjectExistV2(self::$_bucket, $this->_getKey($pasteid));
}
/**
* @inheritDoc
*/
public function createComment($pasteid, $parentid, $commentid, array $comment)
{
if ($this->existsComment($pasteid, $parentid, $commentid)) {
return false;
}
$key = $this->_getKey($pasteid) . '/discussion/' . $parentid . '/' . $commentid;
return $this->_upload($key, $comment);
}
/**
* @inheritDoc
*/
public function readComments($pasteid)
{
$comments = array();
$prefix = $this->_getKey($pasteid) . '/discussion/';
try {
$entries = $this->_listAllObjects($prefix);
foreach ($entries as $entry) {
$object = self::$_client->getObject(array(
'Bucket' => self::$_bucket,
'Key' => $entry['Key'],
));
$body = JSON::decode($object['Body']->getContents());
$items = explode('/', $entry['Key']);
$body['id'] = $items[3];
$body['parentid'] = $items[2];
$slot = $this->getOpenSlot($comments, (int) $object['Metadata']['created']);
$comments[$slot] = $body;
}
} catch (S3Exception $e) {
// no comments found
}
return $comments;
}
/**
* @inheritDoc
*/
public function existsComment($pasteid, $parentid, $commentid)
{
$name = $this->_getKey($pasteid) . '/discussion/' . $parentid . '/' . $commentid;
return self::$_client->doesObjectExistV2(self::$_bucket, $name);
}
/**
* @inheritDoc
*/
public function purgeValues($namespace, $time)
{
$path = self::$_prefix;
if ($path != '') {
$path .= '/';
}
$path .= 'config/' . $namespace;
try {
foreach ($this->_listAllObjects($path) as $object) {
$name = $object['Key'];
if (strlen($name) > strlen($path) && substr($name, strlen($path), 1) !== '/') {
continue;
}
$head = self::$_client->headObject(array(
'Bucket' => self::$_bucket,
'Key' => $name,
));
if (array_key_exists('Metadata', $head) && array_key_exists('value', $head['Metadata'])) {
$value = $head['Metadata']['value'];
if (is_numeric($value) && intval($value) < $time) {
try {
self::$_client->deleteObject(array(
'Bucket' => self::$_bucket,
'Key' => $name,
));
} catch (S3Exception $e) {
// deleted by another instance.
}
}
}
}
} catch (S3Exception $e) {
// no objects in the bucket yet
}
}
/**
* For S3, the value will also be stored in the metadata for the
* namespaces traffic_limiter and purge_limiter.
* @inheritDoc
*/
public function setValue($value, $namespace, $key = '')
{
$prefix = self::$_prefix;
if ($prefix != '') {
$prefix .= '/';
}
if ($key === '') {
$key = $prefix . 'config/' . $namespace;
} else {
$key = $prefix . 'config/' . $namespace . '/' . $key;
}
$metadata = array('namespace' => $namespace);
if ($namespace != 'salt') {
$metadata['value'] = strval($value);
}
try {
self::$_client->putObject(array(
'Bucket' => self::$_bucket,
'Key' => $key,
'Body' => $value,
'ContentType' => 'application/json',
'Metadata' => $metadata,
));
} catch (S3Exception $e) {
error_log('failed to set key ' . $key . ' to ' . self::$_bucket . ', ' .
trim(preg_replace('/\s\s+/', ' ', $e->getMessage())));
return false;
}
return true;
}
/**
* @inheritDoc
*/
public function getValue($namespace, $key = '')
{
$prefix = self::$_prefix;
if ($prefix != '') {
$prefix .= '/';
}
if ($key === '') {
$key = $prefix . 'config/' . $namespace;
} else {
$key = $prefix . 'config/' . $namespace . '/' . $key;
}
try {
$object = self::$_client->getObject(array(
'Bucket' => self::$_bucket,
'Key' => $key,
));
return $object['Body']->getContents();
} catch (S3Exception $e) {
return '';
}
}
/**
* @inheritDoc
*/
protected function _getExpiredPastes($batchsize)
{
$expired = array();
$now = time();
$prefix = self::$_prefix;
if ($prefix != '') {
$prefix .= '/';
}
try {
foreach ($this->_listAllObjects($prefix) as $object) {
$head = self::$_client->headObject(array(
'Bucket' => self::$_bucket,
'Key' => $object['Key'],
));
if (array_key_exists('Metadata', $head) && array_key_exists('expire_date', $head['Metadata'])) {
$expire_at = intval($head['Metadata']['expire_date']);
if ($expire_at != 0 && $expire_at < $now) {
array_push($expired, $object['Key']);
}
}
if (count($expired) > $batchsize) {
break;
}
}
} catch (S3Exception $e) {
// no objects in the bucket yet
}
return $expired;
}
}