function _openid_xrds_discovery

OpenID discovery method: perform a XRDS discovery.

Return value

An array of discovered services and claimed identifier or NULL. See openid_discovery() for more specific information.

See also

http://openid.net/specs/openid-authentication-2_0.html#discovery

hook_openid_discovery_method_info()

openid_discovery()

File

modules/openid/openid.module, line 498

Code

function _openid_xrds_discovery($claimed_id) {
    $services = array();
    $xrds_url = $claimed_id;
    $scheme = @parse_url($xrds_url, PHP_URL_SCHEME);
    if ($scheme == 'http' || $scheme == 'https') {
        // For regular URLs, try Yadis resolution first, then HTML-based discovery
        $headers = array(
            'Accept' => 'application/xrds+xml',
        );
        $result = drupal_http_request($xrds_url, array(
            'headers' => $headers,
        ));
        // Check for HTTP error and make sure, that we reach the target. If the
        // maximum allowed redirects are exhausted, final destination URL isn't
        // reached, but drupal_http_request() doesn't return any error.
        // @todo Remove the check for 200 HTTP result code after the following issue
        // will be fixed: http://drupal.org/node/1096890.
        if (!isset($result->error) && $result->code == 200) {
            // Replace the user-entered claimed_id if we received a redirect.
            if (!empty($result->redirect_url)) {
                $claimed_id = openid_normalize($result->redirect_url);
            }
            if (isset($result->headers['content-type']) && preg_match("/application\\/xrds\\+xml/", $result->headers['content-type'])) {
                // Parse XML document to find URL
                $services = _openid_xrds_parse($result->data);
            }
            else {
                $xrds_url = NULL;
                if (isset($result->headers['x-xrds-location'])) {
                    $xrds_url = $result->headers['x-xrds-location'];
                }
                else {
                    // Look for meta http-equiv link in HTML head
                    $xrds_url = _openid_meta_httpequiv('X-XRDS-Location', $result->data);
                }
                if (!empty($xrds_url)) {
                    $headers = array(
                        'Accept' => 'application/xrds+xml',
                    );
                    $xrds_result = drupal_http_request($xrds_url, array(
                        'headers' => $headers,
                    ));
                    if (!isset($xrds_result->error)) {
                        $services = _openid_xrds_parse($xrds_result->data);
                    }
                }
            }
            // Check for HTML delegation
            if (count($services) == 0) {
                // Look for 2.0 links
                $uri = _openid_link_href('openid2.provider', $result->data);
                $identity = _openid_link_href('openid2.local_id', $result->data);
                $type = 'http://specs.openid.net/auth/2.0/signon';
                // 1.x links
                if (empty($uri)) {
                    $uri = _openid_link_href('openid.server', $result->data);
                    $identity = _openid_link_href('openid.delegate', $result->data);
                    $type = 'http://openid.net/signon/1.1';
                }
                if (!empty($uri)) {
                    $services[] = array(
                        'uri' => $uri,
                        'identity' => $identity,
                        'types' => array(
                            $type,
                        ),
                    );
                }
            }
        }
    }
    if (!empty($services)) {
        return array(
            'services' => $services,
            'claimed_id' => $claimed_id,
        );
    }
}