e107inc/e107

<?php
require_once('SecureLinkDecorator.php');

class NginxSecureLinkMd5Decorator implements SecureLinkDecorator
{
    protected $url = null;
    protected $prefs = array();

    public static $SUPPORTED_VARIABLES = array(
        '$secure_link_expires',
        '$uri',
        '$remote_addr',
        '$host',
    );

    static function supported_variables() {
        return self::$SUPPORTED_VARIABLES;
    }

    function __construct($url, $preferences)
    {
        $this->url = $url;
        $this->prefs = $preferences;
    }

    public function decorate()
    {
        $prefs = $this->prefs;
        $url = $this->url;
        $expiry = intval($prefs['download_security_link_expiry']);
        if ($expiry <= 0)
            $expiry = PHP_INT_MAX;
        else
            $expiry = time() + $expiry;
        $url_parts = parse_url($url);
        $evaluation = str_replace(
            self::supported_variables(),
            array(
                $expiry,
                $url_parts['path'],
                $_SERVER['REMOTE_ADDR'],
                $url_parts['host'],
            ),
            $prefs['download_security_expression']
        );
        $query_string = $url_parts['query'];
        parse_str($query_string, $query_args);
        $query_args['md5'] = str_replace(array('+', '/', '='), array('-', '_', ''), base64_encode(md5($evaluation, true)));
        if (strpos($prefs['download_security_expression'], '$secure_link_expires') !== false)
            $query_args['expires'] = $expiry;
        require_once(__DIR__ . '/../vendor/shim_http_build_url.php');
        return http_build_url($url_parts, array('query' => http_build_query($query_args)));
    }
}