getRequestTarget())['path'] ?? "";
if (!strlen($id) || strpos($id, "/") !== false) {
return new EmptyResponse(404);
}
$id = rawurldecode($id);
// gather the query parameters and act on the "proc" parameter
$method = "do".ucfirst(strtolower($req->getQueryParams()['proc'] ?? "discovery"));
if (!method_exists($this, $method)) {
return new EmptyResponse(404);
} else {
return $this->$method($id, $req);
}
}
/** Produces a user-identifier URL consiustent with the request
*
* This involves reconstructing the scheme and authority based on $_SERVER
* variables; it may fail depending on server configuration
*/
protected function buildIdentifier(ServerRequestInterface $req, bool $baseOnly = false): string {
// construct the base user identifier URL; the user is never checked against the database
$s = $req->getServerParams();
$path = $req->getRequestTarget()['path'];
$https = (strlen($s['HTTPS'] ?? "") && $s['HTTPS'] !== "off");
$port = (int) ($s['SERVER_PORT'] ?? 0);
$port = (!$port || ($https && $port == 443) || (!$https && $port == 80)) ? "" : ":$port";
$base = URL::normalize(($https ? "https" : "http")."://".$s['HTTP_HOST'].$port."/");
return !$baseOnly ? URL::normalize($base.$path) : $base;
}
/** Presents a very basic user profile for discovery purposes
*
* The HTML document itself consists only of link elements and an
* encoding declaration; Link header-fields are also included for
* HEAD requests
*
* Since discovery is publicly accessible, we produce a discovery
* page for all potential user name so as not to facilitate user
* enumeration
*/
protected function doDiscovery(string $user, ServerRequestInterface $req): ResponseInterface {
$base = $this->buildIdentifier($req, true);
$id = $this->buildIdentifier($req);
$urlAuth = $id."?proc=login";
$urlToken = $id."?proc=issue";
$urlService = $base."microsub";
// output an extremely basic identity resource
$html = '';
return new Response($html, 200, [
"Link: <$urlAuth>; rel=\"authorization_endpoint\"",
"Link: <$urlToken>; rel=\"token_endpoint\"",
"Link: <$urlService>; rel=\"microsub\"",
]);
}
/** Handles the authentication/authorization process
*
* Authentication is achieved via an HTTP Basic authentiation
* challenge; once the user successfully logs in a code is issued
* and redirection occurs. Scopes are for all intents and purposes
* ignored and client information is not presented.
*/
protected function doLogin(string $user, ServerRequestInterface $req): ResponseInterface {
if (!$req->getAttribute("authenticated", false)) {
// user has not yet logged in, or has failed to log in
return new EmptyResponse(401);
} else {
// user has logged in
// ensure the logged-in user matches the IndieAuth identifier URL
$id = $req->getAttribute("authenticatedUser");
$query = $req->getQueryParams();
$url = buildIdentifier($req);
if ($user !== $id || URL::normalize($query['me']) !== $url) {
return new EmptyResponse(403);
} else {
$redir = URL::normalize(rawurldecode($query['redirect_uri']));
$state = $query['state'] ?? "";
// check that the redirect URL is an absolute one
if (!URL::absolute($redir)) {
return new EmptyResponse(400);
}
// issue an authorization code and build the redirect URL
$code = Arsse::$db->tokenCreate($id, "microsub.auth", null, Date::add("PT2M"), $query['client_id']);
$next = URL::queryAppend($redir, "code=$code&state=$state");
return new EmptyResponse(302, ["Location: $next"]);
}
}
}
protected function doIssue(string $user, ServerRequestInterface $req): ResponseInterface {
}
}