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|
<?php
/**
+-----------------------------------------------------------------------+
| This file is part of the Roundcube Webmail client |
| |
| Copyright (C) The Roundcube Dev Team |
| |
| Licensed under the GNU General Public License version 3 or |
| any later version with exceptions for skins & plugins. |
| See the README file for a full license statement. |
| |
| PURPOSE: |
| Delivering a specific uploaded file or mail message attachment |
+-----------------------------------------------------------------------+
| Author: Thomas Bruederli <roundcube@gmail.com> |
| Author: Aleksander Machniak <alec@alec.pl> |
+-----------------------------------------------------------------------+
*/
class rcmail_action_mail_get extends rcmail_action_mail_index
{
protected static $attachment;
/**
* Request handler.
*
* @param array $args Arguments from the previous step(s)
*/
public function run($args = [])
{
$rcmail = rcmail::get_instance();
// This resets X-Frame-Options for framed output (#6688)
$rcmail->output->page_headers();
// show loading page
if (!empty($_GET['_preload'])) {
unset($_GET['_preload']);
unset($_GET['_safe']);
$url = $rcmail->url($_GET + ['_mimewarning' => 1, '_embed' => 1]);
$message = $rcmail->gettext('loadingdata');
header('Content-Type: text/html; charset=' . RCUBE_CHARSET);
print "<html>\n<head>\n"
. '<meta http-equiv="refresh" content="0; url='.rcube::Q($url).'">' . "\n"
. '<meta http-equiv="content-type" content="text/html; charset=' . RCUBE_CHARSET . '">' . "\n"
. "</head>\n<body>\n$message\n</body>\n</html>";
exit;
}
$attachment = new rcmail_attachment_handler;
$mimetype = $attachment->mimetype;
$filename = $attachment->filename;
self::$attachment = $attachment;
// show part page
if (!empty($_GET['_frame'])) {
$rcmail->output->set_pagetitle($filename);
// register UI objects
$rcmail->output->add_handlers([
'messagepartframe' => [$this, 'message_part_frame'],
'messagepartcontrols' => [$this, 'message_part_controls'],
]);
$part_id = rcube_utils::get_input_string('_part', rcube_utils::INPUT_GET);
$uid = rcube_utils::get_input_string('_uid', rcube_utils::INPUT_GET);
// message/rfc822 preview (Note: handle also multipart/ parts, they can
// come from Enigma, which replaces message/rfc822 with real mimetype)
if ($part_id && ($mimetype == 'message/rfc822' || strpos($mimetype, 'multipart/') === 0)) {
$uid = preg_replace('/\.[0-9.]+/', '', $uid);
$uid .= '.' . $part_id;
$rcmail->output->set_env('is_message', true);
}
$rcmail->output->set_env('mailbox', $rcmail->storage->get_folder());
$rcmail->output->set_env('uid', $uid);
$rcmail->output->set_env('part', $part_id);
$rcmail->output->set_env('filename', $filename);
$rcmail->output->set_env('mimetype', $mimetype);
$rcmail->output->send('messagepart');
}
// render thumbnail of an image attachment
if (!empty($_GET['_thumb']) && $attachment->is_valid()) {
$thumbnail_size = $rcmail->config->get('image_thumbnail_size', 240);
$file_ident = $attachment->ident;
$thumb_name = 'thumb' . md5($file_ident . ':' . $rcmail->user->ID . ':' . $thumbnail_size);
$cache_file = rcube_utils::temp_filename($thumb_name, false, false);
// render thumbnail image if not done yet
if (!is_file($cache_file) && $attachment->body_to_file($orig_name = rcube_utils::temp_filename('attmnt'))) {
$image = new rcube_image($orig_name);
if ($imgtype = $image->resize($thumbnail_size, $cache_file, true)) {
$mimetype = 'image/' . $imgtype;
}
else {
// Resize failed, we need to check the file mimetype
// So, we do not exit here, but goto generic file body handler below
$_GET['_thumb'] = 0;
$_REQUEST['_embed'] = 1;
}
}
if (!empty($_GET['_thumb'])) {
if (is_file($cache_file)) {
$rcmail->output->future_expire_header(3600);
header('Content-Type: ' . $mimetype);
header('Content-Length: ' . filesize($cache_file));
readfile($cache_file);
}
exit;
}
}
// Handle attachment body (display or download)
if (empty($_GET['_thumb']) && $attachment->is_valid()) {
// require CSRF protected url for downloads
if (!empty($_GET['_download'])) {
$rcmail->request_security_check(rcube_utils::INPUT_GET);
}
$extensions = rcube_mime::get_mime_extensions($mimetype);
// compare file mimetype with the stated content-type headers and file extension to avoid malicious operations
if (!empty($_REQUEST['_embed']) && empty($_REQUEST['_nocheck'])) {
$file_extension = strtolower(pathinfo($filename, PATHINFO_EXTENSION));
// 1. compare filename suffix with expected suffix derived from mimetype
$valid = $file_extension && in_array($file_extension, (array)$extensions)
|| empty($extensions)
|| !empty($_REQUEST['_mimeclass']);
// 2. detect the real mimetype of the attachment part and compare it with the stated mimetype and filename extension
if ($valid || !$file_extension || $mimetype == 'application/octet-stream' || stripos($mimetype, 'text/') === 0) {
$tmp_body = $attachment->body(2048);
// detect message part mimetype
$real_mimetype = rcube_mime::file_content_type($tmp_body, $filename, $mimetype, true, true);
list($real_ctype_primary, $real_ctype_secondary) = explode('/', $real_mimetype);
// accept text/plain with any extension
if ($real_mimetype == 'text/plain' && self::mimetype_compare($real_mimetype, $mimetype)) {
$valid_extension = true;
}
// ignore differences in text/* mimetypes. Filetype detection isn't very reliable here
else if ($real_ctype_primary == 'text' && strpos($mimetype, $real_ctype_primary) === 0) {
$real_mimetype = $mimetype;
$valid_extension = true;
}
// ignore filename extension if mimeclass matches (#1489029)
else if (!empty($_REQUEST['_mimeclass']) && $real_ctype_primary == $_REQUEST['_mimeclass']) {
$valid_extension = true;
}
else {
// get valid file extensions
$extensions = rcube_mime::get_mime_extensions($real_mimetype);
$valid_extension = !$file_extension || empty($extensions) || in_array($file_extension, (array)$extensions);
}
if (
// fix mimetype for files wrongly declared as octet-stream
($mimetype == 'application/octet-stream' && $valid_extension)
// force detected mimetype for images (#8158)
|| (strpos($real_mimetype, 'image/') === 0)
) {
$mimetype = $real_mimetype;
}
// "fix" real mimetype the same way the original is before comparison
$real_mimetype = rcube_mime::fix_mimetype($real_mimetype);
$valid = $valid_extension && self::mimetype_compare($real_mimetype, $mimetype);
}
else {
$real_mimetype = $mimetype;
}
// show warning if validity checks failed
if (!$valid) {
// send blocked.gif for expected images
if (empty($_REQUEST['_mimewarning']) && strpos($mimetype, 'image/') === 0) {
// Do not cache. Failure might be the result of a misconfiguration,
// thus real content should be returned once fixed.
$content = self::get_resource_content('blocked.gif');
$rcmail->output->nocacheing_headers();
header("Content-Type: image/gif");
header("Content-Transfer-Encoding: binary");
header("Content-Length: " . strlen($content));
echo $content;
}
// html warning with a button to load the file anyway
else {
$rcmail->output = new rcmail_html_page();
$rcmail->output->register_inline_warning(
$rcmail->gettext([
'name' => 'attachmentvalidationerror',
'vars' => [
'expected' => $mimetype . (!empty($file_extension) ? rcube::Q(" (.{$file_extension})") : ''),
'detected' => $real_mimetype . (!empty($extensions[0]) ? " (.{$extensions[0]})" : ''),
]
]),
$rcmail->gettext('showanyway'),
$rcmail->url(array_merge($_GET, ['_nocheck' => 1]))
);
$rcmail->output->write();
}
exit;
}
}
// TIFF/WEBP to JPEG conversion, if needed
foreach (['tiff', 'webp'] as $type) {
$img_support = !empty($_SESSION['browser_caps']) && !empty($_SESSION['browser_caps'][$type]);
if (
!empty($_REQUEST['_embed'])
&& !$img_support
&& $attachment->image_type() == 'image/' . $type
&& rcube_image::is_convertable('image/' . $type)
) {
$convert2jpeg = true;
$mimetype = 'image/jpeg';
break;
}
}
// deliver part content
if ($mimetype == 'text/html' && empty($_GET['_download'])) {
$rcmail->output = new rcmail_html_page();
$out = '';
// Check if we have enough memory to handle the message in it
// #1487424: we need up to 10x more memory than the body
if (!rcube_utils::mem_check($attachment->size * 10)) {
$rcmail->output->register_inline_warning(
$rcmail->gettext('messagetoobig'),
$rcmail->gettext('download'),
$rcmail->url(array_merge($_GET, ['_download' => 1]))
);
}
else {
// render HTML body
$out = $attachment->html();
// insert remote objects warning into HTML body
if (self::$REMOTE_OBJECTS) {
$rcmail->output->register_inline_warning(
$rcmail->gettext('blockedresources'),
$rcmail->gettext('allow'),
$rcmail->url(array_merge($_GET, ['_safe' => 1]))
);
} else {
// Use strict security policy to make sure no javascript is executed
// TODO: Make the above "blocked resources button" working with strict policy
// TODO: Move this to rcmail_html_page::write()?
header("Content-Security-Policy: script-src 'none'");
}
}
$rcmail->output->write($out);
exit;
}
// add filename extension if missing
if (!pathinfo($filename, PATHINFO_EXTENSION) && ($extensions = rcube_mime::get_mime_extensions($mimetype))) {
$filename .= '.' . $extensions[0];
}
$rcmail->output->download_headers($filename, [
'type' => $mimetype,
'type_charset' => $attachment->charset,
'disposition' => !empty($_GET['_download']) ? 'attachment' : 'inline',
]);
// handle tiff to jpeg conversion
if (!empty($convert2jpeg)) {
$file_path = rcube_utils::temp_filename('attmnt');
// convert image to jpeg and send it to the browser
if ($attachment->body_to_file($file_path)) {
$image = new rcube_image($file_path);
if ($image->convert(rcube_image::TYPE_JPG, $file_path)) {
header("Content-Length: " . filesize($file_path));
readfile($file_path);
}
}
}
else {
$attachment->output($mimetype);
}
exit;
}
// if we arrive here, the requested part was not found
header('HTTP/1.1 404 Not Found');
exit;
}
/**
* Compares two mimetype strings with making sure that
* e.g. image/bmp and image/x-ms-bmp are treated as equal.
*/
public static function mimetype_compare($type1, $type2)
{
$regexp = '~/(x-ms-|x-)~';
$type1 = preg_replace($regexp, '/', $type1);
$type2 = preg_replace($regexp, '/', $type2);
return $type1 === $type2;
}
/**
* Attachment properties table
*/
public static function message_part_controls($attrib)
{
if (!self::$attachment->is_valid()) {
return '';
}
$rcmail = rcmail::get_instance();
$table = new html_table(['cols' => 2]);
$table->add('title', rcube::Q($rcmail->gettext('namex')).':');
$table->add('header', rcube::Q(self::$attachment->filename));
$table->add('title', rcube::Q($rcmail->gettext('type')).':');
$table->add('header', rcube::Q(self::$attachment->mimetype));
$table->add('title', rcube::Q($rcmail->gettext('size')).':');
$table->add('header', rcube::Q(self::$attachment->size()));
return $table->show($attrib);
}
/**
* Attachment preview frame
*/
public static function message_part_frame($attrib)
{
$rcmail = rcmail::get_instance();
if ($rcmail->output->get_env('is_message')) {
$url = [
'task' => 'mail',
'action' => 'preview',
'uid' => $rcmail->output->get_env('uid'),
'mbox' => $rcmail->output->get_env('mailbox'),
];
}
else {
$mimetype = $rcmail->output->get_env('mimetype');
$url = $_GET;
$url[strpos($mimetype, 'text/') === 0 ? '_embed' : '_preload'] = 1;
unset($url['_frame']);
}
$url['_framed'] = 1; // For proper X-Frame-Options:deny handling
$attrib['src'] = $rcmail->url($url);
$rcmail->output->add_gui_object('messagepartframe', $attrib['id']);
return html::iframe($attrib);
}
}
|
