<?php
/***************************************************************************
- * Copyright (C) 2003-2010 Polytechnique.org *
+ * Copyright (C) 2003-2011 Polytechnique.org *
* http://opensource.polytechnique.org/ *
* *
* This program is free software; you can redistribute it and/or modify *
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA *
***************************************************************************/
-define('PL_DO_AUTH', 300);
-define('PL_FORBIDDEN', 403);
-define('PL_NOT_FOUND', 404);
-define('PL_WIKI', 500);
+// Return values for handlers and hooks. This defines the behavior of both the
+// plat/al engine, and the invidivual hooks.
+define('PL_DO_AUTH', 300); // User should be redirected to the login page.
+define('PL_BAD_REQUEST', 400); // Request is not valid, and could not be interpreted.
+define('PL_FORBIDDEN', 403); // User is not allowed to view page (auth or permission error).
+define('PL_NOT_FOUND', 404); // Page doesn't not exist. Engine will try to offer suggestions.
+define('PL_WIKI', 500); // Page is a wiki page, plat/al engine should yield to the wiki engine.
+define('PL_JSON', 501); // Page is valid, but result should be JSON-encoded, not HTML-encoded.
abstract class PlHook
{
$this->type = $type;
}
- public function needAuth()
- {
- return $this->auth > S::i('auth', AUTH_PUBLIC);
- }
-
public function checkPerms()
{
- if (!$this->perms || $this->auth == AUTH_PUBLIC) { // No perms, no check
- return true;
- }
- $s_perms = S::v('perms');
- return $s_perms->hasFlagCombination($this->perms);
+ // Don't check permissions if there are no permission requirement
+ // (either no requested group membership, or public auth is allowed).
+ return !$this->perms || $this->auth == AUTH_PUBLIC ||
+ Platal::session()->checkPerms($this->perms);
}
public function hasType($type)
return ($this->type & $type) == $type;
}
- abstract protected function run(PlPage &$page, array $args);
+ abstract protected function run(PlPage $page, array $args);
- public function call(PlPage &$page, array $args)
+ public function call(PlPage $page, array $args)
{
global $globals, $session, $platal;
- if ($this->needAuth()) {
+ if (!$session->checkAuth($this->auth)) {
if ($this->hasType(DO_AUTH)) {
if (!$session->start($this->auth)) {
$platal->force_login($page);
}
}
+/** The standard plat/al hook, for interactive requests.
+ * It optionally does active authentication (DO_AUTH). The handler is invoked
+ * with the PlPage object, and with each of the remaining path components.
+ */
class PlStdHook extends PlHook
{
- private $hook;
+ private $callback;
public function __construct($callback, $auth = AUTH_PUBLIC, $perms = 'user', $type = DO_AUTH)
{
parent::__construct($auth, $perms, $type);
- $this->hook = $callback;
+ $this->callback = $callback;
}
- protected function run(PlPage &$page, array $args)
+ protected function run(PlPage $page, array $args)
{
global $session, $platal;
$args[0] = $page;
- $val = call_user_func_array($this->hook, $args);
+ $val = call_user_func_array($this->callback, $args);
if ($val == PL_DO_AUTH) {
if (!$session->start($session->loggedLevel())) {
$platal->force_login($page);
}
- $val = call_user_func_array($this->hook, $args);
+ $val = call_user_func_array($this->callback, $args);
}
return $val;
}
}
+/** A specialized hook for API requests.
+ * It is intended to be used for passive API requests, authenticated either by
+ * an existing session (with a valid XSRF token), or by an alternative single
+ * request auth mechanism implemented by PlSession::apiAuth.
+ *
+ * This hook is suitable for read-write requests against the website, provided
+ * $auth is set appropriately. Note that the auth level is only checked for
+ * session-authenticated users, as "apiAuth" users are assumed to always have
+ * the requested level (use another hook otherwise).
+ *
+ * The callback will be passed as arguments the PlPage, the authenticated
+ * PlUser, the JSON decoded payload, and the remaining path components, as with
+ * any other hook.
+ *
+ * If the callback intends to JSON-encode its returned value, it is advised to
+ * use PlPage::jsonAssign, and return PL_JSON to enable automatic encoding.
+ */
+class PlApiHook extends PlHook
+{
+ private $actualAuth;
+ private $callback;
+
+ public function __construct($callback, $auth = AUTH_PUBLIC, $perms = 'user', $type = NO_AUTH)
+ {
+ // As mentioned above, $auth is only applied for session-based auth
+ // (as opposed to token-based). PlHook is initialized to AUTH_PUBLIC to
+ // avoid it refusing to approve requests; this is important as the user
+ // is not yet authenticated at that point (see below for the actual
+ // permissions check).
+ parent::__construct(AUTH_PUBLIC, $perms, $type);
+ $this->actualAuth = $auth;
+ $this->callback = $callback;
+ }
+
+ private function getEncodedPayload($method)
+ {
+ return $method == "GET" ? "" : file_get_contents("php://input");
+ }
+
+ private function decodePayload($encodedPayload)
+ {
+ return empty($encodedPayload) ? array() : json_decode($encodedPayload, true);
+ }
+
+ protected function run(PlPage $page, array $args)
+ {
+ $method = $_SERVER['REQUEST_METHOD'];
+ $encodedPayload = $this->getEncodedPayload($method);
+ $jsonPayload = $this->decodePayload($encodedPayload);
+ $resource = '/' . implode('/', $args);
+
+ // If the payload wasn't a valid JSON encoded object, bail out early.
+ if (is_null($jsonPayload)) {
+ $page->trigError("Could not decode the JSON-encoded payload sent with the request.");
+ return PL_BAD_REQUEST;
+ }
+
+ // Authenticate the request. Try first with the existing session (which
+ // is less expensive to check), by veryfing that the XSRF token is
+ // valid; otherwise fallbacks to API-type authentication from PlSession.
+ if (S::logged() && S::has_xsrf_token() && Platal::session()->checkAuth($this->actualAuth)) {
+ $user = S::user();
+ } else {
+ $user = Platal::session()->apiAuth($method, $resource, $encodedPayload);
+ }
+
+ // Check the permissions, unless the handler is fully public.
+ if ($this->actualAuth > AUTH_PUBLIC) {
+ if (is_null($user) || !$user->checkPerms($this->perms)) {
+ return PL_FORBIDDEN;
+ }
+ }
+
+ // Invoke the callback, whose signature is (PlPage, PlUser, jsonPayload).
+ array_shift($args);
+ array_unshift($args, $page, $user, $jsonPayload);
+ return call_user_func_array($this->callback, $args);
+ }
+}
+
+/** A specialized hook for token-based requests.
+ * It is intended for purely passive requests (typically for serving CSV or RSS
+ * content outside the browser), and can fallback to regular session-based
+ * authentication when the token is not valid/available.
+ *
+ * Note that $auth is only applied for session-backed authentication; it is
+ * assumed that token-based auth is always enough for the hook (otherwise, just
+ * use PlStdHook above).
+ *
+ * Also, this hook requires that the first two unmatched path components are the
+ * user and token (for instance /<matched path>/<user>/<token>/....). They will
+ * be popped before being passed to the handler, and replaced by the request's
+ * PlUser object.
+ */
+class PlTokenHook extends PlHook
+{
+ private $actualAuth;
+ private $callback;
+
+ public function __construct($callback, $auth = AUTH_PUBLIC, $perms = 'user', $type = NO_AUTH)
+ {
+ // See PlApiHook::__construct.
+ parent::__construct(AUTH_PUBLIC, $perms, $type);
+ $this->actualAuth = $auth;
+ $this->callback = $callback;
+ }
+
+ protected function run(PlPage $page, array $args)
+ {
+ // Retrieve the user, either from the session (less expensive, as it is
+ // already there), or from the in-path (user, token) pair.
+ if (S::logged() && Platal::session()->checkAuth($this->actualAuth)) {
+ $user = S::user();
+ } else {
+ $user = Platal::session()->tokenAuth(@$args[1], @$args[2]);
+ }
+
+ // Check the permissions, unless the handler is fully public.
+ if ($this->actualAuth > AUTH_PUBLIC) {
+ if (is_null($user) || !$user->checkPerms($this->perms)) {
+ return PL_FORBIDDEN;
+ }
+ }
+
+ // Replace the first three remaining elements of the path with the
+ // PlPage and PlUser objects.
+ array_shift($args);
+ $args[0] = $page;
+ $args[1] = $user;
+ return call_user_func_array($this->callback, $args);
+ }
+}
+
+/** A specialized plat/al hook for serving wiki pages.
+ */
class PlWikiHook extends PlHook
{
public function __construct($auth = AUTH_PUBLIC, $perms = 'user', $type = DO_AUTH)
parent::__construct($auth, $perms, $type);
}
- protected function run(PlPage &$page, array $args)
+ protected function run(PlPage $page, array $args)
{
return PL_WIKI;
}
public $aliased = null;
public $children = array();
- public function addChild(array $path, PlHook $hook)
+ public function addChildren(array $hooks)
{
global $platal;
- $next = array_shift($path);
- $alias = null;
- if ($next && $next{0} == '%') {
- $alias = $next;
- $next = $platal->hook_map(substr($next, 1));
- }
- if (!$next) {
- return;
- }
- @$child =& $this->children[$next];
- if (!$child) {
- $child = new PlHookTree();
- $this->children[$next] =& $child;
- $child->aliased = $alias;
- }
- if (empty($path)) {
- $child->hook = $hook;
- } else {
- $child->addChild($path, $hook);
- }
- }
-
- private function findChildAux(array $remain, array $matched, array $aliased)
- {
- $next = @$remain[0];
- if ($this->aliased) {
- $aliased = $matched;
- }
- if (!empty($next)) {
- $child = @$this->children[$next];
- if ($child) {
- array_shift($remain);
- $matched[] = $next;
- return $child->findChildAux($remain, $matched, $aliased);
+ foreach ($hooks as $path=>$hook) {
+ $path = explode('/', $path);
+ $element = $this;
+ foreach ($path as $next) {
+ $alias = null;
+ if ($next{0} == '%') {
+ $alias = $next;
+ $next = $platal->hook_map(substr($next, 1));
+ }
+ if (!isset($element->children[$next])) {
+ $child = new PlHookTree();
+ $child->aliased = $alias;
+ $element->children[$next] = $child;
+ } else {
+ $child = $element->children[$next];
+ }
+ $element = $child;
}
+ $element->hook = $hook;
}
- return array($this->hook, $matched, $remain, $aliased);
}
public function findChild(array $path)
{
- return $this->findChildAux($path, array(), array());
+ $remain = $path;
+ $matched = array();
+ $aliased = array();
+ $element = $this;
+ while (true)
+ {
+ $next = @$remain[0];
+ if ($element->aliased) {
+ $aliased = $matched;
+ }
+ if (empty($next) || !isset($element->children[$next])) {
+ break;
+ }
+ $element = $element->children[$next];
+ array_shift($remain);
+ $matched[] = $next;
+ }
+ return array($element->hook, $matched, $remain, $aliased);
}
private function findNearestChildAux(array $remain, array $matched, array $aliased)
$nearest_sdx = 50;
$match = null;
foreach ($this->children as $path=>$hook) {
- $lev = levenshtein($next, $path);
- if ($lev <= $nearest_lev
- && ($lev < strlen($next) / 2 || strpos($next, $path) !== false
- || strpos($path, $next) !== false)) {
- $sdx = levenshtein(soundex($next), soundex($path));
- if ($lev == $nearest_lev || $sdx < $nearest_sdx) {
- $child = $hook;
- $nearest_lev = $lev;
- $nearest_sdx = $sdx;
- $match = $path;
+ if ($path) {
+ $lev = levenshtein($next, $path);
+ if ($lev <= $nearest_lev
+ && ($lev < strlen($next) / 2 || strpos($next, $path) !== false
+ || strpos($path, $next) !== false)) {
+ $sdx = levenshtein(soundex($next), soundex($path));
+ if ($lev == $nearest_lev || $sdx < $nearest_sdx) {
+ $child = $hook;
+ $nearest_lev = $lev;
+ $nearest_sdx = $sdx;
+ $match = $path;
+ }
}
}
}
foreach ($modules as $module) {
$module = strtolower($module);
$this->mods[$module] = $m = PLModule::factory($module);
- $hooks = $m->handlers();
- foreach ($hooks as $path=>$hook) {
- $this->hooks->addChild(explode('/', $path), $hook);
- }
+ $this->hooks->addChildren($m->handlers());
}
if ($globals->mode == '') {
return $url;
}
- private function call_hook(PlPage &$page)
+ private function call_hook(PlPage $page)
{
$hook = $this->find_hook();
if (empty($hook)) {
/** Show the authentication form.
*/
- abstract public function force_login(PlPage& $page);
+ abstract public function force_login(PlPage $page);
public function run()
{
try {
$page->assign('platal', $this);
- switch ($this->call_hook($page)) {
+ $res = $this->call_hook($page);
+ switch ($res) {
+ case PL_BAD_REQUEST:
+ $this->mods['core']->handler_400($page);
+ break;
+
case PL_FORBIDDEN:
$this->mods['core']->handler_403($page);
break;
}
$page->assign('platal', $this);
- $page->run();
+ if ($res == PL_JSON) {
+ $page->runJSon();
+ } else {
+ $page->run();
+ }
}
public function error403()