gnu-social/extlib/Auth/Yadis/Manager.php

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<?php
/**
* Yadis service manager to be used during yadis-driven authentication
* attempts.
*
* @package OpenID
*/
/**
* The base session class used by the Auth_Yadis_Manager. This
* class wraps the default PHP session machinery and should be
* subclassed if your application doesn't use PHP sessioning.
*
* @package OpenID
*/
class Auth_Yadis_PHPSession {
/**
* Set a session key/value pair.
*
* @param string $name The name of the session key to add.
* @param string $value The value to add to the session.
*/
function set($name, $value)
{
$_SESSION[$name] = $value;
}
/**
* Get a key's value from the session.
*
* @param string $name The name of the key to retrieve.
* @param string $default The optional value to return if the key
* is not found in the session.
* @return string $result The key's value in the session or
* $default if it isn't found.
*/
function get($name, $default=null)
{
if (isset($_SESSION) && array_key_exists($name, $_SESSION)) {
return $_SESSION[$name];
} else {
return $default;
}
}
/**
* Remove a key/value pair from the session.
*
* @param string $name The name of the key to remove.
*/
function del($name)
{
unset($_SESSION[$name]);
}
/**
* Return the contents of the session in array form.
*/
function contents()
{
return $_SESSION;
}
}
/**
* A session helper class designed to translate between arrays and
* objects. Note that the class used must have a constructor that
* takes no parameters. This is not a general solution, but it works
* for dumb objects that just need to have attributes set. The idea
* is that you'll subclass this and override $this->check($data) ->
* bool to implement your own session data validation.
*
* @package OpenID
*/
class Auth_Yadis_SessionLoader {
/**
* Override this.
*
* @access private
*/
function check($data)
{
return true;
}
/**
* Given a session data value (an array), this creates an object
* (returned by $this->newObject()) whose attributes and values
* are those in $data. Returns null if $data lacks keys found in
* $this->requiredKeys(). Returns null if $this->check($data)
* evaluates to false. Returns null if $this->newObject()
* evaluates to false.
*
* @access private
*/
function fromSession($data)
{
if (!$data) {
return null;
}
$required = $this->requiredKeys();
foreach ($required as $k) {
if (!array_key_exists($k, $data)) {
return null;
}
}
if (!$this->check($data)) {
return null;
}
$data = array_merge($data, $this->prepareForLoad($data));
$obj = $this->newObject($data);
if (!$obj) {
return null;
}
foreach ($required as $k) {
$obj->$k = $data[$k];
}
return $obj;
}
/**
* Prepares the data array by making any necessary changes.
* Returns an array whose keys and values will be used to update
* the original data array before calling $this->newObject($data).
*
* @access private
*/
function prepareForLoad($data)
{
return array();
}
/**
* Returns a new instance of this loader's class, using the
* session data to construct it if necessary. The object need
* only be created; $this->fromSession() will take care of setting
* the object's attributes.
*
* @access private
*/
function newObject($data)
{
return null;
}
/**
* Returns an array of keys and values built from the attributes
* of $obj. If $this->prepareForSave($obj) returns an array, its keys
* and values are used to update the $data array of attributes
* from $obj.
*
* @access private
*/
function toSession($obj)
{
$data = array();
foreach ($obj as $k => $v) {
$data[$k] = $v;
}
$extra = $this->prepareForSave($obj);
if ($extra && is_array($extra)) {
foreach ($extra as $k => $v) {
$data[$k] = $v;
}
}
return $data;
}
/**
* Override this.
*
* @access private
*/
function prepareForSave($obj)
{
return array();
}
}
/**
* A concrete loader implementation for Auth_OpenID_ServiceEndpoints.
*
* @package OpenID
*/
class Auth_OpenID_ServiceEndpointLoader extends Auth_Yadis_SessionLoader {
function newObject($data)
{
return new Auth_OpenID_ServiceEndpoint();
}
function requiredKeys()
{
$obj = new Auth_OpenID_ServiceEndpoint();
$data = array();
foreach ($obj as $k => $v) {
$data[] = $k;
}
return $data;
}
function check($data)
{
return is_array($data['type_uris']);
}
}
/**
* A concrete loader implementation for Auth_Yadis_Managers.
*
* @package OpenID
*/
class Auth_Yadis_ManagerLoader extends Auth_Yadis_SessionLoader {
function requiredKeys()
{
return array('starting_url',
'yadis_url',
'services',
'session_key',
'_current',
'stale');
}
function newObject($data)
{
return new Auth_Yadis_Manager($data['starting_url'],
$data['yadis_url'],
$data['services'],
$data['session_key']);
}
function check($data)
{
return is_array($data['services']);
}
function prepareForLoad($data)
{
$loader = new Auth_OpenID_ServiceEndpointLoader();
$services = array();
foreach ($data['services'] as $s) {
$services[] = $loader->fromSession($s);
}
return array('services' => $services);
}
function prepareForSave($obj)
{
$loader = new Auth_OpenID_ServiceEndpointLoader();
$services = array();
foreach ($obj->services as $s) {
$services[] = $loader->toSession($s);
}
return array('services' => $services);
}
}
/**
* The Yadis service manager which stores state in a session and
* iterates over <Service> elements in a Yadis XRDS document and lets
* a caller attempt to use each one. This is used by the Yadis
* library internally.
*
* @package OpenID
*/
class Auth_Yadis_Manager {
/**
* Intialize a new yadis service manager.
*
* @access private
*/
function Auth_Yadis_Manager($starting_url, $yadis_url,
$services, $session_key)
{
// The URL that was used to initiate the Yadis protocol
$this->starting_url = $starting_url;
// The URL after following redirects (the identifier)
$this->yadis_url = $yadis_url;
// List of service elements
$this->services = $services;
$this->session_key = $session_key;
// Reference to the current service object
$this->_current = null;
// Stale flag for cleanup if PHP lib has trouble.
$this->stale = false;
}
/**
* @access private
*/
function length()
{
// How many untried services remain?
return count($this->services);
}
/**
* Return the next service
*
* $this->current() will continue to return that service until the
* next call to this method.
*/
function nextService()
{
if ($this->services) {
$this->_current = array_shift($this->services);
} else {
$this->_current = null;
}
return $this->_current;
}
/**
* @access private
*/
function current()
{
// Return the current service.
// Returns None if there are no services left.
return $this->_current;
}
/**
* @access private
*/
function forURL($url)
{
return in_array($url, array($this->starting_url, $this->yadis_url));
}
/**
* @access private
*/
function started()
{
// Has the first service been returned?
return $this->_current !== null;
}
}
/**
* State management for discovery.
*
* High-level usage pattern is to call .getNextService(discover) in
* order to find the next available service for this user for this
* session. Once a request completes, call .cleanup() to clean up the
* session state.
*
* @package OpenID
*/
class Auth_Yadis_Discovery {
/**
* @access private
*/
var $DEFAULT_SUFFIX = 'auth';
/**
* @access private
*/
var $PREFIX = '_yadis_services_';
/**
* Initialize a discovery object.
*
* @param Auth_Yadis_PHPSession $session An object which
* implements the Auth_Yadis_PHPSession API.
* @param string $url The URL on which to attempt discovery.
* @param string $session_key_suffix The optional session key
* suffix override.
*/
function Auth_Yadis_Discovery($session, $url,
$session_key_suffix = null)
{
/// Initialize a discovery object
$this->session = $session;
$this->url = $url;
if ($session_key_suffix === null) {
$session_key_suffix = $this->DEFAULT_SUFFIX;
}
$this->session_key_suffix = $session_key_suffix;
$this->session_key = $this->PREFIX . $this->session_key_suffix;
}
/**
* Return the next authentication service for the pair of
* user_input and session. This function handles fallback.
*/
function getNextService($discover_cb, $fetcher)
{
$manager = $this->getManager();
if (!$manager || (!$manager->services)) {
$this->destroyManager();
list($yadis_url, $services) = call_user_func_array($discover_cb,
array(
$this->url,
&$fetcher,
));
$manager = $this->createManager($services, $yadis_url);
}
if ($manager) {
$loader = new Auth_Yadis_ManagerLoader();
$service = $manager->nextService();
$this->session->set($this->session_key,
serialize($loader->toSession($manager)));
} else {
$service = null;
}
return $service;
}
/**
* Clean up Yadis-related services in the session and return the
* most-recently-attempted service from the manager, if one
* exists.
*
* @param $force True if the manager should be deleted regardless
* of whether it's a manager for $this->url.
*/
function cleanup($force=false)
{
$manager = $this->getManager($force);
if ($manager) {
$service = $manager->current();
$this->destroyManager($force);
} else {
$service = null;
}
return $service;
}
/**
* @access private
*/
function getSessionKey()
{
// Get the session key for this starting URL and suffix
return $this->PREFIX . $this->session_key_suffix;
}
/**
* @access private
*
* @param $force True if the manager should be returned regardless
* of whether it's a manager for $this->url.
*/
function getManager($force=false)
{
// Extract the YadisServiceManager for this object's URL and
// suffix from the session.
$manager_str = $this->session->get($this->getSessionKey());
$manager = null;
if ($manager_str !== null) {
$loader = new Auth_Yadis_ManagerLoader();
$manager = $loader->fromSession(unserialize($manager_str));
}
if ($manager && ($manager->forURL($this->url) || $force)) {
return $manager;
}
}
/**
* @access private
*/
function createManager($services, $yadis_url = null)
{
$key = $this->getSessionKey();
if ($this->getManager()) {
return $this->getManager();
}
if ($services) {
$loader = new Auth_Yadis_ManagerLoader();
$manager = new Auth_Yadis_Manager($this->url, $yadis_url,
$services, $key);
$this->session->set($this->session_key,
serialize($loader->toSession($manager)));
return $manager;
}
}
/**
* @access private
*
* @param $force True if the manager should be deleted regardless
* of whether it's a manager for $this->url.
*/
function destroyManager($force=false)
{
if ($this->getManager($force) !== null) {
$key = $this->getSessionKey();
$this->session->del($key);
}
}
}