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-rw-r--r--lib/htmlpurifier/library/HTMLPurifier/Filter/ExtractStyleBlocks.php288
1 files changed, 0 insertions, 288 deletions
diff --git a/lib/htmlpurifier/library/HTMLPurifier/Filter/ExtractStyleBlocks.php b/lib/htmlpurifier/library/HTMLPurifier/Filter/ExtractStyleBlocks.php
deleted file mode 100644
index 320aa4f16..000000000
--- a/lib/htmlpurifier/library/HTMLPurifier/Filter/ExtractStyleBlocks.php
+++ /dev/null
@@ -1,288 +0,0 @@
-<?php
-
-// why is this a top level function? Because PHP 5.2.0 doesn't seem to
-// understand how to interpret this filter if it's a static method.
-// It's all really silly, but if we go this route it might be reasonable
-// to coalesce all of these methods into one.
-function htmlpurifier_filter_extractstyleblocks_muteerrorhandler() {}
-
-/**
- * This filter extracts <style> blocks from input HTML, cleans them up
- * using CSSTidy, and then places them in $purifier->context->get('StyleBlocks')
- * so they can be used elsewhere in the document.
- *
- * @note
- * See tests/HTMLPurifier/Filter/ExtractStyleBlocksTest.php for
- * sample usage.
- *
- * @note
- * This filter can also be used on stylesheets not included in the
- * document--something purists would probably prefer. Just directly
- * call HTMLPurifier_Filter_ExtractStyleBlocks->cleanCSS()
- */
-class HTMLPurifier_Filter_ExtractStyleBlocks extends HTMLPurifier_Filter
-{
-
- public $name = 'ExtractStyleBlocks';
- private $_styleMatches = array();
- private $_tidy;
-
- private $_id_attrdef;
- private $_class_attrdef;
- private $_enum_attrdef;
-
- public function __construct() {
- $this->_tidy = new csstidy();
- $this->_id_attrdef = new HTMLPurifier_AttrDef_HTML_ID(true);
- $this->_class_attrdef = new HTMLPurifier_AttrDef_CSS_Ident();
- $this->_enum_attrdef = new HTMLPurifier_AttrDef_Enum(array('first-child', 'link', 'visited', 'active', 'hover', 'focus'));
- }
-
- /**
- * Save the contents of CSS blocks to style matches
- * @param $matches preg_replace style $matches array
- */
- protected function styleCallback($matches) {
- $this->_styleMatches[] = $matches[1];
- }
-
- /**
- * Removes inline <style> tags from HTML, saves them for later use
- * @todo Extend to indicate non-text/css style blocks
- */
- public function preFilter($html, $config, $context) {
- $tidy = $config->get('Filter.ExtractStyleBlocks.TidyImpl');
- if ($tidy !== null) $this->_tidy = $tidy;
- $html = preg_replace_callback('#<style(?:\s.*)?>(.+)</style>#isU', array($this, 'styleCallback'), $html);
- $style_blocks = $this->_styleMatches;
- $this->_styleMatches = array(); // reset
- $context->register('StyleBlocks', $style_blocks); // $context must not be reused
- if ($this->_tidy) {
- foreach ($style_blocks as &$style) {
- $style = $this->cleanCSS($style, $config, $context);
- }
- }
- return $html;
- }
-
- /**
- * Takes CSS (the stuff found in <style>) and cleans it.
- * @warning Requires CSSTidy <http://csstidy.sourceforge.net/>
- * @param $css CSS styling to clean
- * @param $config Instance of HTMLPurifier_Config
- * @param $context Instance of HTMLPurifier_Context
- * @return Cleaned CSS
- */
- public function cleanCSS($css, $config, $context) {
- // prepare scope
- $scope = $config->get('Filter.ExtractStyleBlocks.Scope');
- if ($scope !== null) {
- $scopes = array_map('trim', explode(',', $scope));
- } else {
- $scopes = array();
- }
- // remove comments from CSS
- $css = trim($css);
- if (strncmp('<!--', $css, 4) === 0) {
- $css = substr($css, 4);
- }
- if (strlen($css) > 3 && substr($css, -3) == '-->') {
- $css = substr($css, 0, -3);
- }
- $css = trim($css);
- set_error_handler('htmlpurifier_filter_extractstyleblocks_muteerrorhandler');
- $this->_tidy->parse($css);
- restore_error_handler();
- $css_definition = $config->getDefinition('CSS');
- $html_definition = $config->getDefinition('HTML');
- $new_css = array();
- foreach ($this->_tidy->css as $k => $decls) {
- // $decls are all CSS declarations inside an @ selector
- $new_decls = array();
- foreach ($decls as $selector => $style) {
- $selector = trim($selector);
- if ($selector === '') continue; // should not happen
- // Parse the selector
- // Here is the relevant part of the CSS grammar:
- //
- // ruleset
- // : selector [ ',' S* selector ]* '{' ...
- // selector
- // : simple_selector [ combinator selector | S+ [ combinator? selector ]? ]?
- // combinator
- // : '+' S*
- // : '>' S*
- // simple_selector
- // : element_name [ HASH | class | attrib | pseudo ]*
- // | [ HASH | class | attrib | pseudo ]+
- // element_name
- // : IDENT | '*'
- // ;
- // class
- // : '.' IDENT
- // ;
- // attrib
- // : '[' S* IDENT S* [ [ '=' | INCLUDES | DASHMATCH ] S*
- // [ IDENT | STRING ] S* ]? ']'
- // ;
- // pseudo
- // : ':' [ IDENT | FUNCTION S* [IDENT S*]? ')' ]
- // ;
- //
- // For reference, here are the relevant tokens:
- //
- // HASH #{name}
- // IDENT {ident}
- // INCLUDES ==
- // DASHMATCH |=
- // STRING {string}
- // FUNCTION {ident}\(
- //
- // And the lexical scanner tokens
- //
- // name {nmchar}+
- // nmchar [_a-z0-9-]|{nonascii}|{escape}
- // nonascii [\240-\377]
- // escape {unicode}|\\[^\r\n\f0-9a-f]
- // unicode \\{h}}{1,6}(\r\n|[ \t\r\n\f])?
- // ident -?{nmstart}{nmchar*}
- // nmstart [_a-z]|{nonascii}|{escape}
- // string {string1}|{string2}
- // string1 \"([^\n\r\f\\"]|\\{nl}|{escape})*\"
- // string2 \'([^\n\r\f\\"]|\\{nl}|{escape})*\'
- //
- // We'll implement a subset (in order to reduce attack
- // surface); in particular:
- //
- // - No Unicode support
- // - No escapes support
- // - No string support (by proxy no attrib support)
- // - element_name is matched against allowed
- // elements (some people might find this
- // annoying...)
- // - Pseudo-elements one of :first-child, :link,
- // :visited, :active, :hover, :focus
-
- // handle ruleset
- $selectors = array_map('trim', explode(',', $selector));
- $new_selectors = array();
- foreach ($selectors as $sel) {
- // split on +, > and spaces
- $basic_selectors = preg_split('/\s*([+> ])\s*/', $sel, -1, PREG_SPLIT_DELIM_CAPTURE);
- // even indices are chunks, odd indices are
- // delimiters
- $nsel = null;
- $delim = null; // guaranteed to be non-null after
- // two loop iterations
- for ($i = 0, $c = count($basic_selectors); $i < $c; $i++) {
- $x = $basic_selectors[$i];
- if ($i % 2) {
- // delimiter
- if ($x === ' ') {
- $delim = ' ';
- } else {
- $delim = ' ' . $x . ' ';
- }
- } else {
- // simple selector
- $components = preg_split('/([#.:])/', $x, -1, PREG_SPLIT_DELIM_CAPTURE);
- $sdelim = null;
- $nx = null;
- for ($j = 0, $cc = count($components); $j < $cc; $j ++) {
- $y = $components[$j];
- if ($j === 0) {
- if ($y === '*' || isset($html_definition->info[$y = strtolower($y)])) {
- $nx = $y;
- } else {
- // $nx stays null; this matters
- // if we don't manage to find
- // any valid selector content,
- // in which case we ignore the
- // outer $delim
- }
- } elseif ($j % 2) {
- // set delimiter
- $sdelim = $y;
- } else {
- $attrdef = null;
- if ($sdelim === '#') {
- $attrdef = $this->_id_attrdef;
- } elseif ($sdelim === '.') {
- $attrdef = $this->_class_attrdef;
- } elseif ($sdelim === ':') {
- $attrdef = $this->_enum_attrdef;
- } else {
- throw new HTMLPurifier_Exception('broken invariant sdelim and preg_split');
- }
- $r = $attrdef->validate($y, $config, $context);
- if ($r !== false) {
- if ($r !== true) {
- $y = $r;
- }
- if ($nx === null) {
- $nx = '';
- }
- $nx .= $sdelim . $y;
- }
- }
- }
- if ($nx !== null) {
- if ($nsel === null) {
- $nsel = $nx;
- } else {
- $nsel .= $delim . $nx;
- }
- } else {
- // delimiters to the left of invalid
- // basic selector ignored
- }
- }
- }
- if ($nsel !== null) {
- if (!empty($scopes)) {
- foreach ($scopes as $s) {
- $new_selectors[] = "$s $nsel";
- }
- } else {
- $new_selectors[] = $nsel;
- }
- }
- }
- if (empty($new_selectors)) continue;
- $selector = implode(', ', $new_selectors);
- foreach ($style as $name => $value) {
- if (!isset($css_definition->info[$name])) {
- unset($style[$name]);
- continue;
- }
- $def = $css_definition->info[$name];
- $ret = $def->validate($value, $config, $context);
- if ($ret === false) unset($style[$name]);
- else $style[$name] = $ret;
- }
- $new_decls[$selector] = $style;
- }
- $new_css[$k] = $new_decls;
- }
- // remove stuff that shouldn't be used, could be reenabled
- // after security risks are analyzed
- $this->_tidy->css = $new_css;
- $this->_tidy->import = array();
- $this->_tidy->charset = null;
- $this->_tidy->namespace = null;
- $css = $this->_tidy->print->plain();
- // we are going to escape any special characters <>& to ensure
- // that no funny business occurs (i.e. </style> in a font-family prop).
- if ($config->get('Filter.ExtractStyleBlocks.Escaping')) {
- $css = str_replace(
- array('<', '>', '&'),
- array('\3C ', '\3E ', '\26 '),
- $css
- );
- }
- return $css;
- }
-
-}
-
-// vim: et sw=4 sts=4
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-04 19:15:42 +0000