Initial work adding oauth to api

include/api.php

@@ -2,7 +2,7 @@
 	require_once("bbcode.php");
 	require_once("datetime.php");
 	require_once("conversation.php");
-	
+	require_once("oauth.php");
 	/* 
 	 * Twitter-Like API
 	 *  
@@ -1135,3 +1135,32 @@
 	}
 	api_register_func('api/direct_messages/sent','api_direct_messages_sentbox',true);
 	api_register_func('api/direct_messages','api_direct_messages_inbox',true);
+
+
+
+	function api_oauth_request_token(&$a, $type){
+		try{
+			$oauth = new FKOAuth1();
+			$r = $oauth->fetch_request_token(OAuthRequest::from_request());
+		}catch(Exception $e){
+			echo "error=". OAuthUtil::urlencode_rfc3986($e->getMessage()); killme();
+		}
+		echo "oauth_token=".$r->key."&oauth_secret=".$r->secret;
+		killme();	
+	}
+	function api_oauth_access_token(&$a, $type){
+		try{
+			$oauth = new FKOAuth1();
+			$r = $oauth->fetch_access_token(OAuthRequest::from_request());
+		}catch(Exception $e){
+			echo "error=". OAuthUtil::urlencode_rfc3986($e->getMessage()); killme();
+		}
+		echo "oauth_token=".$r->key."&oauth_secret=".$r->secret;
+		killme();			
+	}
+	function api_oauth_authorize(&$a, $type){
+	}
+	api_register_func('api/oauth/request_token', 'api_oauth_request_token', false);
+	api_register_func('api/oauth/access_token', 'api_oauth_access_token', false);
+	api_register_func('api/oauth/authorize', 'api_oauth_authorize', false);
+

include/oauth.php

@@ -0,0 +1,194 @@
+<?php
+/** 
+ * OAuth server
+ * Based on oauth2-php <http://code.google.com/p/oauth2-php/>
+ * 
+ */
+
+define('TOKEN_DURATION', 300);
+
+require_once("library/OAuth1.php");
+require_once("library/oauth2-php/lib/OAuth2.inc");
+
+class FKOAuthDataStore extends OAuthDataStore {
+  function gen_token(){
+		return md5(base64_encode(pack('N6', mt_rand(), mt_rand(), mt_rand(), mt_rand(), mt_rand(), uniqid())));
+  }
+	
+  function lookup_consumer($consumer_key) {
+      //echo "<pre>"; var_dump($consumer_key); killme();
+	  
+		$r = q("SELECT client_id, pw, redirect_uri FROM clients WHERE client_id='%s'",
+			dbesc($consumer_key)
+		);
+		if (count($r))
+			return new OAuthConsumer($r[0]['client_id'],$r[0]['pw'],$r[0]['redirect_uri']);
+		return null;
+  }
+
+  function lookup_token($consumer, $token_type, $token) {
+		//echo __file__.":".__line__."<pre>"; var_dump($consumer, $token_type, $token); killme();
+		$r = q("SELECT id, secret,scope, expires  FROM tokens WHERE client_id='%s' AND scope='%s' AND id='%s'",
+			dbesc($consumer->key),
+			dbesc($token_type),
+			dbesc($token)
+		);
+		if (count($r)){
+			$ot=new OAuthToken($r[0]['id'],$r[0]['secret']);
+			$ot->scope=$r[0]['scope'];
+			$ot->expires = $r[0]['expires'];
+			return $ot;
+		}
+		return null;
+  }
+
+  function lookup_nonce($consumer, $token, $nonce, $timestamp) {
+		//echo __file__.":".__line__."<pre>"; var_dump($consumer,$key); killme();
+		$r = q("SELECT id, secret  FROM tokens WHERE client_id='%s' AND id='%s' AND expires=%d",
+			dbesc($consumer->key),
+			dbesc($nonce),
+			intval($timestamp)
+		);
+		if (count($r))
+			return new OAuthToken($r[0]['id'],$r[0]['secret']);
+		return null;
+  }
+
+  function new_request_token($consumer, $callback = null) {
+		$key = $this->gen_token();
+		$sec = $this->gen_token();
+		$r = q("INSERT INTO tokens (id, secret, client_id, scope, expires) VALUES ('%s','%s','%s','%s', UNIX_TIMESTAMP()+%d)",
+				dbesc($key),
+				dbesc($sec),
+				dbesc($consumer->key),
+				'request',
+				intval(TOKEN_DURATION));
+		if (!$r) return null;
+		return new OAuthToken($key,$sec);
+  }
+
+  function new_access_token($token, $consumer, $verifier = null) {
+    // return a new access token attached to this consumer
+    // for the user associated with this token if the request token
+    // is authorized
+    // should also invalidate the request token
+    
+    $ret=Null;
+    
+    if (!is_null($token) && $token->expires > time()){
+		
+		$key = $this->gen_token();
+		$sec = $this->gen_token();
+		$r = q("INSERT INTO tokens (id, secret, client_id, scope, expires) VALUES ('%s','%s','%s','%s', UNIX_TIMESTAMP()+%d)",
+				dbesc($key),
+				dbesc($sec),
+				dbesc($consumer->$key),
+				'access',
+				intval(TOKEN_DURATION));
+		if ($r)
+			$ret = new OAuthToken($key,$sec);		
+	}
+		
+		
+	q("DELETE FROM tokens WHERE id='%s'", $token->key);
+		
+    return $ret;
+    
+  }
+}
+
+class FKOAuth1 extends OAuthServer {
+	function __construct() {
+		parent::__construct(new FKOAuthDataStore());
+		$this->add_signature_method(new OAuthSignatureMethod_PLAINTEXT());
+	}
+}
+
+class FKOAuth2 extends OAuth2 {
+
+	private function db_secret($client_secret){
+		return hash('whirlpool',$client_secret);
+	}
+
+	public function addClient($client_id, $client_secret, $redirect_uri) {
+		$client_secret = $this->db_secret($client_secret);
+		$r = q("INSERT INTO clients (client_id, pw, redirect_uri) VALUES ('%s', '%s', '%s')",
+			dbesc($client_id),
+			dbesc($client_secret),
+			dbesc($redirect_uri)
+		);
+		  
+		return $r;
+	}
+
+	protected function checkClientCredentials($client_id, $client_secret = NULL) {
+		$client_secret = $this->db_secret($client_secret);
+		
+		$r = q("SELECT pw FROM clients WHERE client_id = '%s'",
+			dbesc($client_id));
+
+		if ($client_secret === NULL)
+			return $result !== FALSE;
+
+		return $result["client_secret"] == $client_secret;
+	}
+
+	protected function getRedirectUri($client_id) {
+		$r = q("SELECT redirect_uri FROM clients WHERE client_id = '%s'",
+				dbesc($client_id));
+		if ($r === FALSE)
+			return FALSE;
+
+		return isset($r[0]["redirect_uri"]) && $r[0]["redirect_uri"] ? $r[0]["redirect_uri"] : NULL;
+	}
+
+	protected function getAccessToken($oauth_token) {
+		$r = q("SELECT client_id, expires, scope FROM tokens WHERE id = '%s'",
+				dbesc($oauth_token));
+	
+		if (count($r))
+			return $r[0];
+		return null;
+	}
+
+
+	
+	protected function setAccessToken($oauth_token, $client_id, $expires, $scope = NULL) {
+		$r = q("INSERT INTO tokens (id, client_id, expires, scope) VALUES ('%s', '%s', %d, '%s')",
+				dbesc($oauth_token),
+				dbesc($client_id),
+				intval($expires),
+				dbesc($scope));
+				
+		return $r;
+	}
+
+	protected function getSupportedGrantTypes() {
+		return array(
+		  OAUTH2_GRANT_TYPE_AUTH_CODE,
+		);
+	}
+
+
+	protected function getAuthCode($code) {
+		$r = q("SELECT id, client_id, redirect_uri, expires, scope FROM auth_codes WHERE id = '%s'",
+				dbesc($code));
+		
+		if (count($r))
+			return $r[0];
+		return null;
+	}
+
+	protected function setAuthCode($code, $client_id, $redirect_uri, $expires, $scope = NULL) {
+		$r = q("INSERT INTO auth_codes 
+					(id, client_id, redirect_uri, expires, scope) VALUES 
+					('%s', '%s', '%s', %d, '%s')",
+				dbesc($code),
+				dbesc($client_id),
+				dbesc($redirect_uri),
+				intval($expires),
+				dbesc($scope));
+		return $r;	  
+	}	
+	
+}

library/oauth2-php/CHANGELOG.txt

@@ -0,0 +1,98 @@
+oauth2-php revision xxx, xxxx-xx-xx (development version)
+----------------------
+
+oauth2-php revision 23, 2011-01-25
+----------------------
+* introduce Drupal style getVariable() and setVariable, replace legacy
+  variable get/set functions.
+* remove hardcode PHP display_error and errror_reporting, as this should
+  be manually implement within 3rd party integration.
+* make verbose error as configurable and default disable, as this should
+  be manually enable within 3rd party integration.
+* add lib/OAuth2Client.inc and lib/OAuth2Exception.inc for client-side
+  implementation.
+
+oauth2-php revision 21, 2010-12-18
+----------------------
+* cleanup tabs and trailing whitespace at the end.
+* remove server/examples/mongo/lib/oauth.php and
+  server/examples/pdo/lib/oauth.php, so only keep single copy as
+  lib /oauth.php.
+* issue #5: Wrong variable name in get_access_token() in pdo_oatuh.php.
+* issue #6: mysql_create_tables.sql should allow scope to be NULL.
+* issue #7: authorize_client_response_type() is never used.
+* issue #9: Change "redirect_uri" filtering from FILTER_VALIDATE_URL to
+  FILTER_SANITIZE_URL.
+* better coding syntax for error() and callback_error().
+* better pdo_oauth2.php variable naming with change to
+  mysql_create_tables.sql.
+* change REGEX_CLIENT_ID as 3-32 characters long, so will work with md5()
+  result directly.
+* debug linkage to oauth2.php during previous commit.
+* debug redirect_uri check for AUTH_CODE_GRANT_TYPE, clone from
+  get_authorize_params().
+* update mysql_create_tables.sql with phpmyadmin export format.
+* rename library files, prepare for adding client-side implementation.
+* code cleanup with indent and spacing.
+* code cleanup true/false/null with TRUE/FALSE/NULL.
+* rename constants with OAUTH2_ prefix, prevent 3rd party integration
+  conflict.
+* remove HTTP 400 response constant, as useless refer to draft v10.
+* merge ERROR_INVALID_CLIENT_ID and ERROR_UNAUTHORIZED_CLIENT as
+  OAUTH2_ERROR_INVALID_CLIENT, as refer to that of draft v9 to v10 changes.
+* improve constants comment with doxygen syntax.
+* update class function call naming.
+* coding style clean up.
+* update part of documents.
+* change expirseRefreshToken() as unsetRefreshToken().
+* update token and auth code generation as md5() result, simpler for manual
+  debug with web browser.
+* update all documents.
+* restructure @ingroup.
+* rename checkRestrictedClientResponseTypes() as
+  checkRestrictedAuthResponseType().
+* rename checkRestrictedClientGrantTypes() as checkRestrictedGrantType().
+* rename error() as errorJsonResponse().
+* rename errorCallback() as errorDoRedirectUriCallback().
+* rename send401Unauthorized() as errorWWWAuthenticateResponseHeader(),
+  update support with different HTTP status code.
+* update __construct() with array input.
+* update finishClientAuthorization() with array input.
+* add get/set functions for $access_token_lifetime, $auth_code_lifetime and
+  $refresh_token_lifetime.
+* fix a lots of typos.
+* document all sample server implementation.
+* more documents.
+* add config.doxy for doxygen default setup.
+* add MIT LICENSE.txt.
+* add CHANGELOG.txt.
+
+oauth2-php revision 9, 2010-09-04
+----------------------
+- fixes for issues #2 and #4, updates oauth lib in the example folders to
+  the latest version in the 'lib' folder.
+- updates server library to revision 10 of the OAuth 2.0 spec.
+- adds an option for more verbose error messages to be returned in the JSON
+  response.
+- adds method to be overridden for expiring used refresh tokens.
+- fixes bug checking token expiration.
+- makes some more methods protected instead of private so they can be
+  overridden.
+- fixes issue #1 http://code.google.com/p/oauth2-php/issues/detail?id=1
+
+oauth2-php revision 7, 2010-06-29
+----------------------
+- fixed mongo connection constants.
+- updated store_refresh_token to include expires time.
+- changed example server directory structure
+- corrected "false" return result on get_stored_auth_code.
+- implemented PDO example adapter.
+- corrected an error in assertion grant type.
+- updated for ietf draft v9:
+  http://tools.ietf.org/html/draft-ietf-oauth-v2-09.
+- updated updated to support v9 lib.
+- added mysql table creation script.
+
+oauth2-php revision 0, 2010-06-27
+----------------------
+- initial commit.

library/oauth2-php/LICENSE.txt

@@ -0,0 +1,21 @@
+The MIT License
+
+Copyright (c) 2010 Tim Ridgely <tim@opendining.net>
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.

library/oauth2-php/lib/OAuth2Client.inc

@@ -0,0 +1,721 @@
+<?php
+
+/**
+ * The default Cache Lifetime (in seconds).
+ */
+define("OAUTH2_DEFAULT_EXPIRES_IN", 3600);
+
+/**
+ * The default Base domain for the Cookie.
+ */
+define("OAUTH2_DEFAULT_BASE_DOMAIN", '');
+
+/**
+ * OAuth2.0 draft v10 client-side implementation.
+ *
+ * @author Originally written by Naitik Shah <naitik@facebook.com>.
+ * @author Update to draft v10 by Edison Wong <hswong3i@pantarei-design.com>.
+ *
+ * @sa <a href="https://github.com/facebook/php-sdk">Facebook PHP SDK</a>.
+ */
+abstract class OAuth2Client {
+
+  /**
+   * Array of persistent variables stored.
+   */
+  protected $conf = array();
+
+  /**
+   * Returns a persistent variable.
+   *
+   * To avoid problems, always use lower case for persistent variable names.
+   *
+   * @param $name
+   *   The name of the variable to return.
+   * @param $default
+   *   The default value to use if this variable has never been set.
+   *
+   * @return
+   *   The value of the variable.
+   */
+  public function getVariable($name, $default = NULL) {
+    return isset($this->conf[$name]) ? $this->conf[$name] : $default;
+  }
+
+  /**
+   * Sets a persistent variable.
+   *
+   * To avoid problems, always use lower case for persistent variable names.
+   *
+   * @param $name
+   *   The name of the variable to set.
+   * @param $value
+   *   The value to set.
+   */
+  public function setVariable($name, $value) {
+    $this->conf[$name] = $value;
+    return $this;
+  }
+
+  // Stuff that should get overridden by subclasses.
+  //
+  // I don't want to make these abstract, because then subclasses would have
+  // to implement all of them, which is too much work.
+  //
+  // So they're just stubs. Override the ones you need.
+
+  /**
+   * Initialize a Drupal OAuth2.0 Application.
+   *
+   * @param $config
+   *   An associative array as below:
+   *   - base_uri: The base URI for the OAuth2.0 endpoints.
+   *   - code: (optional) The authorization code.
+   *   - username: (optional) The username.
+   *   - password: (optional) The password.
+   *   - client_id: (optional) The application ID.
+   *   - client_secret: (optional) The application secret.
+   *   - authorize_uri: (optional) The end-user authorization endpoint URI.
+   *   - access_token_uri: (optional) The token endpoint URI.
+   *   - services_uri: (optional) The services endpoint URI.
+   *   - cookie_support: (optional) TRUE to enable cookie support.
+   *   - base_domain: (optional) The domain for the cookie.
+   *   - file_upload_support: (optional) TRUE if file uploads are enabled.
+   */
+  public function __construct($config = array()) {
+    // We must set base_uri first.
+    $this->setVariable('base_uri', $config['base_uri']);
+    unset($config['base_uri']);
+
+    // Use predefined OAuth2.0 params, or get it from $_REQUEST.
+    foreach (array('code', 'username', 'password') as $name) {
+      if (isset($config[$name]))
+        $this->setVariable($name, $config[$name]);
+      else if (isset($_REQUEST[$name]) && !empty($_REQUEST[$name]))
+        $this->setVariable($name, $_REQUEST[$name]);
+      unset($config[$name]);
+    }
+
+    // Endpoint URIs.
+    foreach (array('authorize_uri', 'access_token_uri', 'services_uri') as $name) {
+      if (isset($config[$name]))
+        if (substr($config[$name], 0, 4) == "http")
+          $this->setVariable($name, $config[$name]);
+        else
+          $this->setVariable($name, $this->getVariable('base_uri') . $config[$name]);
+      unset($config[$name]);
+    }
+
+    // Other else configurations.
+    foreach ($config as $name => $value) {
+      $this->setVariable($name, $value);
+    }
+  }
+
+  /**
+   * Try to get session object from custom method.
+   *
+   * By default we generate session object based on access_token response, or
+   * if it is provided from server with $_REQUEST. For sure, if it is provided
+   * by server it should follow our session object format.
+   *
+   * Session object provided by server can ensure the correct expirse and
+   * base_domain setup as predefined in server, also you may get more useful
+   * information for custom functionality, too. BTW, this may require for
+   * additional remote call overhead.
+   *
+   * You may wish to override this function with your custom version due to
+   * your own server-side implementation.
+   *
+   * @param $access_token
+   *   (optional) A valid access token in associative array as below:
+   *   - access_token: A valid access_token generated by OAuth2.0
+   *     authorization endpoint.
+   *   - expires_in: (optional) A valid expires_in generated by OAuth2.0
+   *     authorization endpoint.
+   *   - refresh_token: (optional) A valid refresh_token generated by OAuth2.0
+   *     authorization endpoint.
+   *   - scope: (optional) A valid scope generated by OAuth2.0
+   *     authorization endpoint.
+   *
+   *  @return
+   *    A valid session object in associative array for setup cookie, and
+   *    NULL if not able to generate it with custom method.
+   */
+  protected function getSessionObject($access_token = NULL) {
+    $session = NULL;
+
+    // Try generate local version of session cookie.
+    if (!empty($access_token) && isset($access_token['access_token'])) {
+      $session['access_token'] = $access_token['access_token'];
+      $session['base_domain'] = $this->getVariable('base_domain', OAUTH2_DEFAULT_BASE_DOMAIN);
+      $session['expirse'] = isset($access_token['expires_in']) ? time() + $access_token['expires_in'] : time() + $this->getVariable('expires_in', OAUTH2_DEFAULT_EXPIRES_IN);
+      $session['refresh_token'] = isset($access_token['refresh_token']) ? $access_token['refresh_token'] : '';
+      $session['scope'] = isset($access_token['scope']) ? $access_token['scope'] : '';
+      $session['secret'] = md5(base64_encode(pack('N6', mt_rand(), mt_rand(), mt_rand(), mt_rand(), mt_rand(), uniqid())));
+
+      // Provide our own signature.
+      $sig = self::generateSignature(
+        $session,
+        $this->getVariable('client_secret')
+      );
+      $session['sig'] = $sig;
+    }
+
+    // Try loading session from $_REQUEST.
+    if (!$session && isset($_REQUEST['session'])) {
+      $session = json_decode(
+        get_magic_quotes_gpc()
+          ? stripslashes($_REQUEST['session'])
+          : $_REQUEST['session'],
+        TRUE
+      );
+    }
+
+    return $session;
+  }
+
+  /**
+   * Make an API call.
+   *
+   * Support both OAuth2.0 or normal GET/POST API call, with relative
+   * or absolute URI.
+   *
+   * If no valid OAuth2.0 access token found in session object, this function
+   * will automatically switch as normal remote API call without "oauth_token"
+   * parameter.
+   *
+   * Assume server reply in JSON object and always decode during return. If
+   * you hope to issue a raw query, please use makeRequest().
+   *
+   * @param $path
+   *   The target path, relative to base_path/service_uri or an absolute URI.
+   * @param $method
+   *   (optional) The HTTP method (default 'GET').
+   * @param $params
+   *   (optional The GET/POST parameters.
+   *
+   * @return
+   *   The JSON decoded response object.
+   *
+   * @throws OAuth2Exception
+   */
+  public function api($path, $method = 'GET', $params = array()) {
+    if (is_array($method) && empty($params)) {
+      $params = $method;
+      $method = 'GET';
+    }
+
+    // json_encode all params values that are not strings.
+    foreach ($params as $key => $value) {
+      if (!is_string($value)) {
+        $params[$key] = json_encode($value);
+      }
+    }
+
+    $result = json_decode($this->makeOAuth2Request(
+      $this->getUri($path),
+      $method,
+      $params
+    ), TRUE);
+
+    // Results are returned, errors are thrown.
+    if (is_array($result) && isset($result['error'])) {
+      $e = new OAuth2Exception($result);
+      switch ($e->getType()) {
+        // OAuth 2.0 Draft 10 style.
+        case 'invalid_token':
+          $this->setSession(NULL);
+        default:
+          $this->setSession(NULL);
+      }
+      throw $e;
+    }
+    return $result;
+  }
+
+  // End stuff that should get overridden.
+
+  /**
+   * Default options for cURL.
+   */
+  public static $CURL_OPTS = array(
+    CURLOPT_CONNECTTIMEOUT => 10,
+    CURLOPT_RETURNTRANSFER => TRUE,
+    CURLOPT_HEADER         => TRUE,
+    CURLOPT_TIMEOUT        => 60,
+    CURLOPT_USERAGENT      => 'oauth2-draft-v10',
+    CURLOPT_HTTPHEADER     => array("Accept: application/json"),
+  );
+
+  /**
+   * Set the Session.
+   *
+   * @param $session
+   *   (optional) The session object to be set. NULL if hope to frush existing
+   *   session object.
+   * @param $write_cookie
+   *   (optional) TRUE if a cookie should be written. This value is ignored
+   *   if cookie support has been disabled.
+   *
+   * @return
+   *   The current OAuth2.0 client-side instance.
+   */
+  public function setSession($session = NULL, $write_cookie = TRUE) {
+    $this->setVariable('_session', $this->validateSessionObject($session));
+    $this->setVariable('_session_loaded', TRUE);
+    if ($write_cookie) {
+      $this->setCookieFromSession($this->getVariable('_session'));
+    }
+    return $this;
+  }
+
+  /**
+   * Get the session object.
+   *
+   * This will automatically look for a signed session via custom method,
+   * OAuth2.0 grant type with authorization_code, OAuth2.0 grant type with
+   * password, or cookie that we had already setup.
+   *
+   * @return
+   *   The valid session object with OAuth2.0 infomration, and NULL if not
+   *   able to discover any cases.
+   */
+  public function getSession() {
+    if (!$this->getVariable('_session_loaded')) {
+      $session = NULL;
+      $write_cookie = TRUE;
+
+      // Try obtain login session by custom method.
+      $session = $this->getSessionObject(NULL);
+      $session = $this->validateSessionObject($session);
+
+      // grant_type == authorization_code.
+      if (!$session && $this->getVariable('code')) {
+        $access_token = $this->getAccessTokenFromAuthorizationCode($this->getVariable('code'));
+        $session = $this->getSessionObject($access_token);
+        $session = $this->validateSessionObject($session);
+      }
+
+      // grant_type == password.
+      if (!$session && $this->getVariable('username') && $this->getVariable('password')) {
+        $access_token = $this->getAccessTokenFromPassword($this->getVariable('username'), $this->getVariable('password'));
+        $session = $this->getSessionObject($access_token);
+        $session = $this->validateSessionObject($session);
+      }
+
+      // Try loading session from cookie if necessary.
+      if (!$session && $this->getVariable('cookie_support')) {
+        $cookie_name = $this->getSessionCookieName();
+        if (isset($_COOKIE[$cookie_name])) {
+          $session = array();
+          parse_str(trim(
+            get_magic_quotes_gpc()
+              ? stripslashes($_COOKIE[$cookie_name])
+              : $_COOKIE[$cookie_name],
+            '"'
+          ), $session);
+          $session = $this->validateSessionObject($session);
+          // Write only if we need to delete a invalid session cookie.
+          $write_cookie = empty($session);
+        }
+      }
+
+      $this->setSession($session, $write_cookie);
+    }
+
+    return $this->getVariable('_session');
+  }
+
+  /**
+   * Gets an OAuth2.0 access token from session.
+   *
+   * This will trigger getSession() and so we MUST initialize with required
+   * configuration.
+   *
+   * @return
+   *   The valid OAuth2.0 access token, and NULL if not exists in session.
+   */
+  public function getAccessToken() {
+    $session = $this->getSession();
+    return isset($session['access_token']) ? $session['access_token'] : NULL;
+  }
+
+  /**
+   * Get access token from OAuth2.0 token endpoint with authorization code.
+   *
+   * This function will only be activated if both access token URI, client
+   * identifier and client secret are setup correctly.
+   *
+   * @param $code
+   *   Authorization code issued by authorization server's authorization
+   *   endpoint.
+   *
+   * @return
+   *   A valid OAuth2.0 JSON decoded access token in associative array, and
+   *   NULL if not enough parameters or JSON decode failed.
+   */
+  private function getAccessTokenFromAuthorizationCode($code) {
+    if ($this->getVariable('access_token_uri') && $this->getVariable('client_id') && $this->getVariable('client_secret')) {
+      return json_decode($this->makeRequest(
+        $this->getVariable('access_token_uri'),
+        'POST',
+        array(
+          'grant_type' => 'authorization_code',
+          'client_id' => $this->getVariable('client_id'),
+          'client_secret' => $this->getVariable('client_secret'),
+          'code' => $code,
+          'redirect_uri' => $this->getCurrentUri(),
+        )
+      ), TRUE);
+    }
+    return NULL;
+  }
+
+  /**
+   * Get access token from OAuth2.0 token endpoint with basic user
+   * credentials.
+   *
+   * This function will only be activated if both username and password
+   * are setup correctly.
+   *
+   * @param $username
+   *   Username to be check with.
+   * @param $password
+   *   Password to be check with.
+   *
+   * @return
+   *   A valid OAuth2.0 JSON decoded access token in associative array, and
+   *   NULL if not enough parameters or JSON decode failed.
+   */
+  private function getAccessTokenFromPassword($username, $password) {
+    if ($this->getVariable('access_token_uri') && $this->getVariable('client_id') && $this->getVariable('client_secret')) {
+      return json_decode($this->makeRequest(
+        $this->getVariable('access_token_uri'),
+        'POST',
+        array(
+          'grant_type' => 'password',
+          'client_id' => $this->getVariable('client_id'),
+          'client_secret' => $this->getVariable('client_secret'),
+          'username' => $username,
+          'password' => $password,
+        )
+      ), TRUE);
+    }
+    return NULL;
+  }
+
+  /**
+   * Make an OAuth2.0 Request.
+   *
+   * Automatically append "oauth_token" in query parameters if not yet
+   * exists and able to discover a valid access token from session. Otherwise
+   * just ignore setup with "oauth_token" and handle the API call AS-IS, and
+   * so may issue a plain API call without OAuth2.0 protection.
+   *
+   * @param $path
+   *   The target path, relative to base_path/service_uri or an absolute URI.
+   * @param $method
+   *   (optional) The HTTP method (default 'GET').
+   * @param $params
+   *   (optional The GET/POST parameters.
+   *
+   * @return
+   *   The JSON decoded response object.
+   *
+   * @throws OAuth2Exception
+   */
+  protected function makeOAuth2Request($path, $method = 'GET', $params = array()) {
+    if ((!isset($params['oauth_token']) || empty($params['oauth_token'])) && $oauth_token = $this->getAccessToken()) {
+      $params['oauth_token'] = $oauth_token;
+    }
+    return $this->makeRequest($path, $method, $params);
+  }
+
+  /**
+   * Makes an HTTP request.
+   *
+   * This method can be overriden by subclasses if developers want to do
+   * fancier things or use something other than cURL to make the request.
+   *
+   * @param $path
+   *   The target path, relative to base_path/service_uri or an absolute URI.
+   * @param $method
+   *   (optional) The HTTP method (default 'GET').
+   * @param $params
+   *   (optional The GET/POST parameters.
+   * @param $ch
+   *   (optional) An initialized curl handle
+   *
+   * @return
+   *   The JSON decoded response object.
+   */
+  protected function makeRequest($path, $method = 'GET', $params = array(), $ch = NULL) {
+    if (!$ch)
+      $ch = curl_init();
+
+    $opts = self::$CURL_OPTS;
+    if ($params) {
+      switch ($method) {
+        case 'GET':
+          $path .= '?' . http_build_query($params, NULL, '&');
+          break;
+        // Method override as we always do a POST.
+        default:
+          if ($this->getVariable('file_upload_support')) {
+            $opts[CURLOPT_POSTFIELDS] = $params;
+          }
+          else {
+            $opts[CURLOPT_POSTFIELDS] = http_build_query($params, NULL, '&');
+          }
+      }
+    }
+    $opts[CURLOPT_URL] = $path;
+
+    // Disable the 'Expect: 100-continue' behaviour. This causes CURL to wait
+    // for 2 seconds if the server does not support this header.
+    if (isset($opts[CURLOPT_HTTPHEADER])) {
+      $existing_headers = $opts[CURLOPT_HTTPHEADER];
+      $existing_headers[] = 'Expect:';
+      $opts[CURLOPT_HTTPHEADER] = $existing_headers;
+    }
+    else {
+      $opts[CURLOPT_HTTPHEADER] = array('Expect:');
+    }
+
+    curl_setopt_array($ch, $opts);
+    $result = curl_exec($ch);
+
+    if (curl_errno($ch) == 60) { // CURLE_SSL_CACERT
+      error_log('Invalid or no certificate authority found, using bundled information');
+      curl_setopt($ch, CURLOPT_CAINFO,
+                  dirname(__FILE__) . '/fb_ca_chain_bundle.crt');
+      $result = curl_exec($ch);
+    }
+
+    if ($result === FALSE) {
+      $e = new OAuth2Exception(array(
+        'code' => curl_errno($ch),
+        'message' => curl_error($ch),
+      ));
+      curl_close($ch);
+      throw $e;
+    }
+    curl_close($ch);
+
+    // Split the HTTP response into header and body.
+    list($headers, $body) = explode("\r\n\r\n", $result);
+    $headers = explode("\r\n", $headers);
+
+    // We catch HTTP/1.1 4xx or HTTP/1.1 5xx error response.
+    if (strpos($headers[0], 'HTTP/1.1 4') !== FALSE || strpos($headers[0], 'HTTP/1.1 5') !== FALSE) {
+      $result = array(
+        'code' => 0,
+        'message' => '',
+      );
+
+      if (preg_match('/^HTTP\/1.1 ([0-9]{3,3}) (.*)$/', $headers[0], $matches)) {
+        $result['code'] = $matches[1];
+        $result['message'] = $matches[2];
+      }
+
+      // In case retrun with WWW-Authenticate replace the description.
+      foreach ($headers as $header) {
+        if (preg_match("/^WWW-Authenticate:.*error='(.*)'/", $header, $matches)) {
+          $result['error'] = $matches[1];
+        }
+      }
+
+      return json_encode($result);
+    }
+
+    return $body;
+  }
+
+  /**
+   * The name of the cookie that contains the session object.
+   *
+   * @return
+   *   The cookie name.
+   */
+  private function getSessionCookieName() {
+    return 'oauth2_' . $this->getVariable('client_id');
+  }
+
+  /**
+   * Set a JS Cookie based on the _passed in_ session.
+   *
+   * It does not use the currently stored session - you need to explicitly
+   * pass it in.
+   *
+   * @param $session
+   *   The session to use for setting the cookie.
+   */
+  protected function setCookieFromSession($session = NULL) {
+    if (!$this->getVariable('cookie_support'))
+      return;
+
+    $cookie_name = $this->getSessionCookieName();
+    $value = 'deleted';
+    $expires = time() - 3600;
+    $base_domain = $this->getVariable('base_domain', OAUTH2_DEFAULT_BASE_DOMAIN);
+    if ($session) {
+      $value = '"' . http_build_query($session, NULL, '&') . '"';
+      $base_domain = isset($session['base_domain']) ? $session['base_domain'] : $base_domain;
+      $expires = isset($session['expires']) ? $session['expires'] : time() + $this->getVariable('expires_in', OAUTH2_DEFAULT_EXPIRES_IN);
+    }
+
+    // Prepend dot if a domain is found.
+    if ($base_domain)
+      $base_domain = '.' . $base_domain;
+
+    // If an existing cookie is not set, we dont need to delete it.
+    if ($value == 'deleted' && empty($_COOKIE[$cookie_name]))
+      return;
+
+    if (headers_sent())
+      error_log('Could not set cookie. Headers already sent.');
+    else
+      setcookie($cookie_name, $value, $expires, '/', $base_domain);
+  }
+
+  /**
+   * Validates a session_version = 3 style session object.
+   *
+   * @param $session
+   *   The session object.
+   *
+   * @return
+   *   The session object if it validates, NULL otherwise.
+   */
+  protected function validateSessionObject($session) {
+    // Make sure some essential fields exist.
+    if (is_array($session) && isset($session['access_token']) && isset($session['sig'])) {
+      // Validate the signature.
+      $session_without_sig = $session;
+      unset($session_without_sig['sig']);
+
+      $expected_sig = self::generateSignature(
+        $session_without_sig,
+        $this->getVariable('client_secret')
+      );
+
+      if ($session['sig'] != $expected_sig) {
+        error_log('Got invalid session signature in cookie.');
+        $session = NULL;
+      }
+    }
+    else {
+      $session = NULL;
+    }
+    return $session;
+  }
+
+  /**
+   * Since $_SERVER['REQUEST_URI'] is only available on Apache, we
+   * generate an equivalent using other environment variables.
+   */
+  function getRequestUri() {
+    if (isset($_SERVER['REQUEST_URI'])) {
+      $uri = $_SERVER['REQUEST_URI'];
+    }
+    else {
+      if (isset($_SERVER['argv'])) {
+        $uri = $_SERVER['SCRIPT_NAME'] . '?' . $_SERVER['argv'][0];
+      }
+      elseif (isset($_SERVER['QUERY_STRING'])) {
+        $uri = $_SERVER['SCRIPT_NAME'] . '?' . $_SERVER['QUERY_STRING'];
+      }
+      else {
+        $uri = $_SERVER['SCRIPT_NAME'];
+      }
+    }
+    // Prevent multiple slashes to avoid cross site requests via the Form API.
+    $uri = '/' . ltrim($uri, '/');
+
+    return $uri;
+  }
+
+  /**
+   * Returns the Current URL.
+   *
+   * @return
+   *   The current URL.
+   */
+  protected function getCurrentUri() {
+    $protocol = isset($_SERVER['HTTPS']) && $_SERVER['HTTPS'] == 'on'
+      ? 'https://'
+      : 'http://';
+    $current_uri = $protocol . $_SERVER['HTTP_HOST'] . $this->getRequestUri();
+    $parts = parse_url($current_uri);
+
+    $query = '';
+    if (!empty($parts['query'])) {
+      $params = array();
+      parse_str($parts['query'], $params);
+      $params = array_filter($params);
+      if (!empty($params)) {
+        $query = '?' . http_build_query($params, NULL, '&');
+      }
+    }
+
+    // Use port if non default.
+    $port = isset($parts['port']) &&
+      (($protocol === 'http://' && $parts['port'] !== 80) || ($protocol === 'https://' && $parts['port'] !== 443))
+      ? ':' . $parts['port'] : '';
+
+    // Rebuild.
+    return $protocol . $parts['host'] . $port . $parts['path'] . $query;
+  }
+
+  /**
+   * Build the URL for given path and parameters.
+   *
+   * @param $path
+   *   (optional) The path.
+   * @param $params
+   *   (optional) The query parameters in associative array.
+   *
+   * @return
+   *   The URL for the given parameters.
+   */
+  protected function getUri($path = '', $params = array()) {
+    $url = $this->getVariable('services_uri') ? $this->getVariable('services_uri') : $this->getVariable('base_uri');
+
+    if (!empty($path))
+      if (substr($path, 0, 4) == "http")
+        $url = $path;
+      else
+        $url = rtrim($url, '/') . '/' . ltrim($path, '/');
+
+    if (!empty($params))
+      $url .= '?' . http_build_query($params, NULL, '&');
+
+    return $url;
+  }
+
+  /**
+   * Generate a signature for the given params and secret.
+   *
+   * @param $params
+   *   The parameters to sign.
+   * @param $secret
+   *   The secret to sign with.
+   *
+   * @return
+   *   The generated signature
+   */
+  protected function generateSignature($params, $secret) {
+    // Work with sorted data.
+    ksort($params);
+
+    // Generate the base string.
+    $base_string = '';
+    foreach ($params as $key => $value) {
+      $base_string .= $key . '=' . $value;
+    }
+    $base_string .= $secret;
+
+    return md5($base_string);
+  }
+}

library/oauth2-php/lib/OAuth2Exception.inc

@@ -0,0 +1,85 @@
+<?php
+
+/**
+ * OAuth2.0 draft v10 exception handling.
+ *
+ * @author Originally written by Naitik Shah <naitik@facebook.com>.
+ * @author Update to draft v10 by Edison Wong <hswong3i@pantarei-design.com>.
+ *
+ * @sa <a href="https://github.com/facebook/php-sdk">Facebook PHP SDK</a>.
+ */
+class OAuth2Exception extends Exception {
+
+  /**
+   * The result from the API server that represents the exception information.
+   */
+  protected $result;
+
+  /**
+   * Make a new API Exception with the given result.
+   *
+   * @param $result
+   *   The result from the API server.
+   */
+  public function __construct($result) {
+    $this->result = $result;
+
+    $code = isset($result['code']) ? $result['code'] : 0;
+
+    if (isset($result['error'])) {
+      // OAuth 2.0 Draft 10 style
+      $message = $result['error'];
+    }
+    elseif (isset($result['message'])) {
+      // cURL style
+      $message = $result['message'];
+    }
+    else {
+      $message = 'Unknown Error. Check getResult()';
+    }
+
+    parent::__construct($message, $code);
+  }
+
+  /**
+   * Return the associated result object returned by the API server.
+   *
+   * @returns
+   *   The result from the API server.
+   */
+  public function getResult() {
+    return $this->result;
+  }
+
+  /**
+   * Returns the associated type for the error. This will default to
+   * 'Exception' when a type is not available.
+   *
+   * @return
+   *   The type for the error.
+   */
+  public function getType() {
+    if (isset($this->result['error'])) {
+      $message = $this->result['error'];
+      if (is_string($message)) {
+        // OAuth 2.0 Draft 10 style
+        return $message;
+      }
+    }
+    return 'Exception';
+  }
+
+  /**
+   * To make debugging easier.
+   *
+   * @returns
+   *   The string representation of the error.
+   */
+  public function __toString() {
+    $str = $this->getType() . ': ';
+    if ($this->code != 0) {
+      $str .= $this->code . ': ';
+    }
+    return $str . $this->message;
+  }
+}