htmlpurifier/library/HTMLPurifier/AttrDef/URI.php

<?php

/**
 * Validates a URI as defined by RFC 3986.
 * @note Scheme-specific mechanics deferred to HTMLPurifier_URIScheme
 */
class HTMLPurifier_AttrDef_URI extends HTMLPurifier_AttrDef
{

    protected $parser;
    protected $embedsResource;

    /**
     * @param $embeds_resource_resource Does the URI here result in an extra HTTP request?
     */
    public function __construct($embeds_resource = false) {
        $this->parser = new HTMLPurifier_URIParser();
        $this->embedsResource = (bool) $embeds_resource;
    }

    public function make($string) {
        $embeds = (bool) $string;
        return new HTMLPurifier_AttrDef_URI($embeds);
    }

    public function validate($uri, $config, $context) {

        if ($config->get('URI.Disable')) return false;

        $uri = $this->parseCDATA($uri);

        // parse the URI
        $uri = $this->parser->parse($uri);
        if ($uri === false) return false;

        // add embedded flag to context for validators
        $context->register('EmbeddedURI', $this->embedsResource);

        $ok = false;
        do {

            // generic validation
            $result = $uri->validate($config, $context);
            if (!$result) break;

            // chained filtering
            $uri_def = $config->getDefinition('URI');
            $result = $uri_def->filter($uri, $config, $context);
            if (!$result) break;

            // scheme-specific validation
            $scheme_obj = $uri->getSchemeObj($config, $context);
            if (!$scheme_obj) break;
            if ($this->embedsResource && !$scheme_obj->browsable) break;
            $result = $scheme_obj->validate($uri, $config, $context);
            if (!$result) break;

            // Post chained filtering
            $result = $uri_def->postFilter($uri, $config, $context);
            if (!$result) break;

            // survived gauntlet
            $ok = true;

        } while (false);

        $context->destroy('EmbeddedURI');
        if (!$ok) return false;

        // back to string
        return $uri->toString();

    }

}

// vim: et sw=4 sts=4