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Diffstat (limited to 'lib/htmlpurifier/library/HTMLPurifier/Filter/ExtractStyleBlocks.php')
-rw-r--r--lib/htmlpurifier/library/HTMLPurifier/Filter/ExtractStyleBlocks.php175
1 files changed, 11 insertions, 164 deletions
diff --git a/lib/htmlpurifier/library/HTMLPurifier/Filter/ExtractStyleBlocks.php b/lib/htmlpurifier/library/HTMLPurifier/Filter/ExtractStyleBlocks.php
index 320aa4f16..bbf78a663 100644
--- a/lib/htmlpurifier/library/HTMLPurifier/Filter/ExtractStyleBlocks.php
+++ b/lib/htmlpurifier/library/HTMLPurifier/Filter/ExtractStyleBlocks.php
@@ -1,11 +1,5 @@
<?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')
@@ -27,15 +21,8 @@ class HTMLPurifier_Filter_ExtractStyleBlocks extends HTMLPurifier_Filter
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'));
}
/**
@@ -90,166 +77,27 @@ class HTMLPurifier_Filter_ExtractStyleBlocks extends HTMLPurifier_Filter
$css = substr($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[] = $nsel;
+ if ($selector[0] === '+') {
+ if ($selector !== '' && $selector[0] === '+') continue;
+ }
+ if (!empty($scopes)) {
+ $new_selector = array(); // because multiple ones are possible
+ $selectors = array_map('trim', explode(',', $selector));
+ foreach ($scopes as $s1) {
+ foreach ($selectors as $s2) {
+ $new_selector[] = "$s1 $s2";
}
}
+ $selector = implode(', ', $new_selector); // now it's a string
}
- if (empty($new_selectors)) continue;
- $selector = implode(', ', $new_selectors);
foreach ($style as $name => $value) {
if (!isset($css_definition->info[$name])) {
unset($style[$name]);
@@ -262,11 +110,10 @@ class HTMLPurifier_Filter_ExtractStyleBlocks extends HTMLPurifier_Filter
}
$new_decls[$selector] = $style;
}
- $new_css[$k] = $new_decls;
+ $this->_tidy->css[$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;
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-05 09:20:15 +0000