nextcloud/lib/private/response.php

222 lines
6.5 KiB
PHP

<?php
/**
* Copyright (c) 2011 Bart Visscher bartv@thisnet.nl
* This file is licensed under the Affero General Public License version 3 or
* later.
* See the COPYING-README file.
*/
class OC_Response {
const STATUS_FOUND = 304;
const STATUS_NOT_MODIFIED = 304;
const STATUS_TEMPORARY_REDIRECT = 307;
const STATUS_NOT_FOUND = 404;
const STATUS_INTERNAL_SERVER_ERROR = 500;
const STATUS_SERVICE_UNAVAILABLE = 503;
/**
* @brief Enable response caching by sending correct HTTP headers
* @param integer $cache_time time to cache the response
* >0 cache time in seconds
* 0 and <0 enable default browser caching
* null cache indefinitly
*/
static public function enableCaching($cache_time = null) {
if (is_numeric($cache_time)) {
header('Pragma: public');// enable caching in IE
if ($cache_time > 0) {
self::setExpiresHeader('PT'.$cache_time.'S');
header('Cache-Control: max-age='.$cache_time.', must-revalidate');
}
else {
self::setExpiresHeader(0);
header("Cache-Control: must-revalidate, post-check=0, pre-check=0");
}
}
else {
header('Cache-Control: cache');
header('Pragma: cache');
}
}
/**
* @brief disable browser caching
* @see enableCaching with cache_time = 0
*/
static public function disableCaching() {
self::enableCaching(0);
}
/**
* @brief Set response status
* @param int $status a HTTP status code, see also the STATUS constants
*/
static public function setStatus($status) {
$protocol = $_SERVER['SERVER_PROTOCOL'];
switch($status) {
case self::STATUS_NOT_MODIFIED:
$status = $status . ' Not Modified';
break;
case self::STATUS_TEMPORARY_REDIRECT:
if ($protocol == 'HTTP/1.1') {
$status = $status . ' Temporary Redirect';
break;
} else {
$status = self::STATUS_FOUND;
// fallthrough
}
case self::STATUS_FOUND;
$status = $status . ' Found';
break;
case self::STATUS_NOT_FOUND;
$status = $status . ' Not Found';
break;
case self::STATUS_INTERNAL_SERVER_ERROR;
$status = $status . ' Internal Server Error';
break;
case self::STATUS_SERVICE_UNAVAILABLE;
$status = $status . ' Service Unavailable';
break;
}
header($protocol.' '.$status);
}
/**
* @brief Send redirect response
* @param string $location to redirect to
*/
static public function redirect($location) {
self::setStatus(self::STATUS_TEMPORARY_REDIRECT);
header('Location: '.$location);
}
/**
* @brief Set reponse expire time
* @param string|DateTime $expires date-time when the response expires
* string for DateInterval from now
* DateTime object when to expire response
*/
static public function setExpiresHeader($expires) {
if (is_string($expires) && $expires[0] == 'P') {
$interval = $expires;
$expires = new DateTime('now');
$expires->add(new DateInterval($interval));
}
if ($expires instanceof DateTime) {
$expires->setTimezone(new DateTimeZone('GMT'));
$expires = $expires->format(DateTime::RFC2822);
}
header('Expires: '.$expires);
}
/**
* Checks and set ETag header, when the request matches sends a
* 'not modified' response
* @param string $etag token to use for modification check
*/
static public function setETagHeader($etag) {
if (empty($etag)) {
return;
}
$etag = '"'.$etag.'"';
if (isset($_SERVER['HTTP_IF_NONE_MATCH']) &&
trim($_SERVER['HTTP_IF_NONE_MATCH']) == $etag) {
self::setStatus(self::STATUS_NOT_MODIFIED);
exit;
}
header('ETag: '.$etag);
}
/**
* Checks and set Last-Modified header, when the request matches sends a
* 'not modified' response
* @param int|DateTime|string $lastModified time when the reponse was last modified
*/
static public function setLastModifiedHeader($lastModified) {
if (empty($lastModified)) {
return;
}
if (is_int($lastModified)) {
$lastModified = gmdate(DateTime::RFC2822, $lastModified);
}
if ($lastModified instanceof DateTime) {
$lastModified = $lastModified->format(DateTime::RFC2822);
}
if (isset($_SERVER['HTTP_IF_MODIFIED_SINCE']) &&
trim($_SERVER['HTTP_IF_MODIFIED_SINCE']) == $lastModified) {
self::setStatus(self::STATUS_NOT_MODIFIED);
exit;
}
header('Last-Modified: '.$lastModified);
}
/**
* Sets the content disposition header (with possible workarounds)
* @param string $filename file name
* @param string $type disposition type, either 'attachment' or 'inline'
*/
static public function setContentDispositionHeader( $filename, $type = 'attachment' ) {
if (OC_Request::isUserAgent(array(
OC_Request::USER_AGENT_IE,
OC_Request::USER_AGENT_ANDROID_MOBILE_CHROME,
OC_Request::USER_AGENT_FREEBOX
))) {
header( 'Content-Disposition: ' . rawurlencode($type) . '; filename="' . rawurlencode( $filename ) . '"' );
} else {
header( 'Content-Disposition: ' . rawurlencode($type) . '; filename*=UTF-8\'\'' . rawurlencode( $filename )
. '; filename="' . rawurlencode( $filename ) . '"' );
}
}
/**
* @brief Send file as response, checking and setting caching headers
* @param string $filepath of file to send
*/
static public function sendFile($filepath) {
$fp = fopen($filepath, 'rb');
if ($fp) {
self::setLastModifiedHeader(filemtime($filepath));
self::setETagHeader(md5_file($filepath));
header('Content-Length: '.filesize($filepath));
fpassthru($fp);
}
else {
self::setStatus(self::STATUS_NOT_FOUND);
}
}
/*
* This function adds some security related headers to all requests served via base.php
* The implementation of this function has to happen here to ensure that all third-party
* components (e.g. SabreDAV) also benefit from this headers.
*/
public static function addSecurityHeaders() {
header('X-XSS-Protection: 1; mode=block'); // Enforce browser based XSS filters
header('X-Content-Type-Options: nosniff'); // Disable sniffing the content type for IE
// iFrame Restriction Policy
$xFramePolicy = OC_Config::getValue('xframe_restriction', true);
if ($xFramePolicy) {
header('X-Frame-Options: Sameorigin'); // Disallow iFraming from other domains
}
// Content Security Policy
// If you change the standard policy, please also change it in config.sample.php
$policy = OC_Config::getValue('custom_csp_policy',
'default-src \'self\'; '
. 'script-src \'self\' \'unsafe-eval\'; '
. 'style-src \'self\' \'unsafe-inline\'; '
. 'frame-src *; '
. 'img-src *; '
. 'font-src \'self\' data:; '
. 'media-src *');
header('Content-Security-Policy:' . $policy);
// https://developers.google.com/webmasters/control-crawl-index/docs/robots_meta_tag
header('X-Robots-Tag: none');
}
}