diff options
Diffstat (limited to 'vendor/ezyang/htmlpurifier/library/HTMLPurifier/AttrDef/CSS.php')
-rw-r--r-- | vendor/ezyang/htmlpurifier/library/HTMLPurifier/AttrDef/CSS.php | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/vendor/ezyang/htmlpurifier/library/HTMLPurifier/AttrDef/CSS.php b/vendor/ezyang/htmlpurifier/library/HTMLPurifier/AttrDef/CSS.php new file mode 100644 index 000000000..ad2cb90ad --- /dev/null +++ b/vendor/ezyang/htmlpurifier/library/HTMLPurifier/AttrDef/CSS.php @@ -0,0 +1,136 @@ +<?php + +/** + * Validates the HTML attribute style, otherwise known as CSS. + * @note We don't implement the whole CSS specification, so it might be + * difficult to reuse this component in the context of validating + * actual stylesheet declarations. + * @note If we were really serious about validating the CSS, we would + * tokenize the styles and then parse the tokens. Obviously, we + * are not doing that. Doing that could seriously harm performance, + * but would make these components a lot more viable for a CSS + * filtering solution. + */ +class HTMLPurifier_AttrDef_CSS extends HTMLPurifier_AttrDef +{ + + /** + * @param string $css + * @param HTMLPurifier_Config $config + * @param HTMLPurifier_Context $context + * @return bool|string + */ + public function validate($css, $config, $context) + { + $css = $this->parseCDATA($css); + + $definition = $config->getCSSDefinition(); + $allow_duplicates = $config->get("CSS.AllowDuplicates"); + + + // According to the CSS2.1 spec, the places where a + // non-delimiting semicolon can appear are in strings + // escape sequences. So here is some dumb hack to + // handle quotes. + $len = strlen($css); + $accum = ""; + $declarations = array(); + $quoted = false; + for ($i = 0; $i < $len; $i++) { + $c = strcspn($css, ";'\"", $i); + $accum .= substr($css, $i, $c); + $i += $c; + if ($i == $len) break; + $d = $css[$i]; + if ($quoted) { + $accum .= $d; + if ($d == $quoted) { + $quoted = false; + } + } else { + if ($d == ";") { + $declarations[] = $accum; + $accum = ""; + } else { + $accum .= $d; + $quoted = $d; + } + } + } + if ($accum != "") $declarations[] = $accum; + + $propvalues = array(); + $new_declarations = ''; + + /** + * Name of the current CSS property being validated. + */ + $property = false; + $context->register('CurrentCSSProperty', $property); + + foreach ($declarations as $declaration) { + if (!$declaration) { + continue; + } + if (!strpos($declaration, ':')) { + continue; + } + list($property, $value) = explode(':', $declaration, 2); + $property = trim($property); + $value = trim($value); + $ok = false; + do { + if (isset($definition->info[$property])) { + $ok = true; + break; + } + if (ctype_lower($property)) { + break; + } + $property = strtolower($property); + if (isset($definition->info[$property])) { + $ok = true; + break; + } + } while (0); + if (!$ok) { + continue; + } + // inefficient call, since the validator will do this again + if (strtolower(trim($value)) !== 'inherit') { + // inherit works for everything (but only on the base property) + $result = $definition->info[$property]->validate( + $value, + $config, + $context + ); + } else { + $result = 'inherit'; + } + if ($result === false) { + continue; + } + if ($allow_duplicates) { + $new_declarations .= "$property:$result;"; + } else { + $propvalues[$property] = $result; + } + } + + $context->destroy('CurrentCSSProperty'); + + // procedure does not write the new CSS simultaneously, so it's + // slightly inefficient, but it's the only way of getting rid of + // duplicates. Perhaps config to optimize it, but not now. + + foreach ($propvalues as $prop => $value) { + $new_declarations .= "$prop:$value;"; + } + + return $new_declarations ? $new_declarations : false; + + } + +} + +// vim: et sw=4 sts=4 |