kopia lustrzana https://github.com/friendica/friendica
75 wiersze
2.7 KiB
Plaintext
75 wiersze
2.7 KiB
Plaintext
![]() |
Filter.ExtractStyleBlocks
|
||
|
TYPE: bool
|
||
|
VERSION: 3.1.0
|
||
|
DEFAULT: false
|
||
|
EXTERNAL: CSSTidy
|
||
|
--DESCRIPTION--
|
||
|
<p>
|
||
|
This directive turns on the style block extraction filter, which removes
|
||
|
<code>style</code> blocks from input HTML, cleans them up with CSSTidy,
|
||
|
and places them in the <code>StyleBlocks</code> context variable, for further
|
||
|
use by you, usually to be placed in an external stylesheet, or a
|
||
|
<code>style</code> block in the <code>head</code> of your document.
|
||
|
</p>
|
||
|
<p>
|
||
|
Sample usage:
|
||
|
</p>
|
||
|
<pre><![CDATA[
|
||
|
<?php
|
||
|
header('Content-type: text/html; charset=utf-8');
|
||
|
echo '<?xml version="1.0" encoding="UTF-8"?>';
|
||
|
?>
|
||
|
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
|
||
|
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
|
||
|
<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en">
|
||
|
<head>
|
||
|
<title>Filter.ExtractStyleBlocks</title>
|
||
|
<?php
|
||
|
require_once '/path/to/library/HTMLPurifier.auto.php';
|
||
|
require_once '/path/to/csstidy.class.php';
|
||
|
|
||
|
$dirty = '<style>body {color:#F00;}</style> Some text';
|
||
|
|
||
|
$config = HTMLPurifier_Config::createDefault();
|
||
|
$config->set('Filter', 'ExtractStyleBlocks', true);
|
||
|
$purifier = new HTMLPurifier($config);
|
||
|
|
||
|
$html = $purifier->purify($dirty);
|
||
|
|
||
|
// This implementation writes the stylesheets to the styles/ directory.
|
||
|
// You can also echo the styles inside the document, but it's a bit
|
||
|
// more difficult to make sure they get interpreted properly by
|
||
|
// browsers; try the usual CSS armoring techniques.
|
||
|
$styles = $purifier->context->get('StyleBlocks');
|
||
|
$dir = 'styles/';
|
||
|
if (!is_dir($dir)) mkdir($dir);
|
||
|
$hash = sha1($_GET['html']);
|
||
|
foreach ($styles as $i => $style) {
|
||
|
file_put_contents($name = $dir . $hash . "_$i");
|
||
|
echo '<link rel="stylesheet" type="text/css" href="'.$name.'" />';
|
||
|
}
|
||
|
?>
|
||
|
</head>
|
||
|
<body>
|
||
|
<div>
|
||
|
<?php echo $html; ?>
|
||
|
</div>
|
||
|
</b]]><![CDATA[ody>
|
||
|
</html>
|
||
|
]]></pre>
|
||
|
<p>
|
||
|
<strong>Warning:</strong> It is possible for a user to mount an
|
||
|
imagecrash attack using this CSS. Counter-measures are difficult;
|
||
|
it is not simply enough to limit the range of CSS lengths (using
|
||
|
relative lengths with many nesting levels allows for large values
|
||
|
to be attained without actually specifying them in the stylesheet),
|
||
|
and the flexible nature of selectors makes it difficult to selectively
|
||
|
disable lengths on image tags (HTML Purifier, however, does disable
|
||
|
CSS width and height in inline styling). There are probably two effective
|
||
|
counter measures: an explicit width and height set to auto in all
|
||
|
images in your document (unlikely) or the disabling of width and
|
||
|
height (somewhat reasonable). Whether or not these measures should be
|
||
|
used is left to the reader.
|
||
|
</p>
|
||
|
--# vim: et sw=4 sts=4
|