to mitigate html download with CSP: no blacklisting just IE, only whitelist tested browsers and versions

This commit is contained in:
Ralf Becker 2013-10-01 09:49:06 +00:00
parent e46f2f987c
commit d49c460c5f

View File

@ -671,16 +671,23 @@ class vfs_webdav_server extends HTTP_WebDAV_Server_Filesystem
// mitigate risk of html downloads by using CSP or force download for IE
if (!$this->force_download && in_array($options['mimetype'], array('text/html', 'application/xhtml+xml')))
{
if (html::$user_agent == 'msie') // according to http://caniuse.com/contentsecuritypolicy not supported in IE
{
$this->force_download = true;
}
else
// use CSP only for current user-agents/versions I was able to positivly test
if (html::$user_agent == 'chrome' && html::$ua_version >= 24 ||
// mobile FF 24 on Android does NOT honor CSP!
html::$user_agent == 'firefox' && !html::$ua_mobile && html::$ua_version >= 24 ||
html::$user_agent == 'safari' && !html::$ua_mobile && html::$ua_version >= 536 || // OS X
html::$user_agent == 'safari' && html::$ua_mobile && html::$ua_version >= 9537) // iOS 7
{
$csp = "script-src 'none'"; // forbid to execute any javascript
header("Content-Security-Policy: $csp");
header("X-Webkit-CSP: $csp"); // Chrome: <= 24, Safari incl. iOS
header("X-Content-Security-Policy: $csp"); // FF <= 22
//header("X-Content-Security-Policy: $csp"); // FF <= 22
//error_log(__METHOD__."('$options[path]') ".html::$user_agent.'/'.html::$ua_version.(html::$ua_mobile?'/mobile':'').": using Content-Security-Policy: $csp");
}
else // everything else get's a Content-dispostion: attachment, to be on save side
{
//error_log(__METHOD__."('$options[path]') ".html::$user_agent.'/'.html::$ua_version.(html::$ua_mobile?'/mobile':'').": using Content-disposition: attachment");
$this->force_download = true;
}
}
if ($this->force_download)