diff options
Diffstat (limited to 'library/vendor/HTMLPurifier/AttrDef/CSS/URI.php')
-rw-r--r-- | library/vendor/HTMLPurifier/AttrDef/CSS/URI.php | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/library/vendor/HTMLPurifier/AttrDef/CSS/URI.php b/library/vendor/HTMLPurifier/AttrDef/CSS/URI.php new file mode 100644 index 0000000..6617aca --- /dev/null +++ b/library/vendor/HTMLPurifier/AttrDef/CSS/URI.php @@ -0,0 +1,77 @@ +<?php + +/** + * Validates a URI in CSS syntax, which uses url('http://example.com') + * @note While theoretically speaking a URI in a CSS document could + * be non-embedded, as of CSS2 there is no such usage so we're + * generalizing it. This may need to be changed in the future. + * @warning Since HTMLPurifier_AttrDef_CSS blindly uses semicolons as + * the separator, you cannot put a literal semicolon in + * in the URI. Try percent encoding it, in that case. + */ +class HTMLPurifier_AttrDef_CSS_URI extends HTMLPurifier_AttrDef_URI +{ + + public function __construct() + { + parent::__construct(true); // always embedded + } + + /** + * @param string $uri_string + * @param HTMLPurifier_Config $config + * @param HTMLPurifier_Context $context + * @return bool|string + */ + public function validate($uri_string, $config, $context) + { + // parse the URI out of the string and then pass it onto + // the parent object + + $uri_string = $this->parseCDATA($uri_string); + if (strpos($uri_string, 'url(') !== 0) { + return false; + } + $uri_string = substr($uri_string, 4); + if (strlen($uri_string) == 0) { + return false; + } + $new_length = strlen($uri_string) - 1; + if ($uri_string[$new_length] != ')') { + return false; + } + $uri = trim(substr($uri_string, 0, $new_length)); + + if (!empty($uri) && ($uri[0] == "'" || $uri[0] == '"')) { + $quote = $uri[0]; + $new_length = strlen($uri) - 1; + if ($uri[$new_length] !== $quote) { + return false; + } + $uri = substr($uri, 1, $new_length - 1); + } + + $uri = $this->expandCSSEscape($uri); + + $result = parent::validate($uri, $config, $context); + + if ($result === false) { + return false; + } + + // extra sanity check; should have been done by URI + $result = str_replace(array('"', "\\", "\n", "\x0c", "\r"), "", $result); + + // suspicious characters are ()'; we're going to percent encode + // them for safety. + $result = str_replace(array('(', ')', "'"), array('%28', '%29', '%27'), $result); + + // there's an extra bug where ampersands lose their escaping on + // an innerHTML cycle, so a very unlucky query parameter could + // then change the meaning of the URL. Unfortunately, there's + // not much we can do about that... + return "url(\"$result\")"; + } +} + +// vim: et sw=4 sts=4 |