3 files changed, 490 insertions, 33 deletions

diff --git a/mod/twitter_api/vendors/twitteroauth/OAuth.php b/mod/twitter_api/vendors/twitteroauth/OAuth.php
index e132a5bc8..e76304146 100644
--- a/mod/twitter_api/vendors/twitteroauth/OAuth.php
+++ b/mod/twitter_api/vendors/twitteroauth/OAuth.php
@@ -1,6 +1,12 @@
 <?php
 // vim: foldmethod=marker
 
+/* Generic exception class
+ */
+class OAuthException extends Exception {
+  // pass
+}
+
 class OAuthConsumer {
   public $key;
   public $secret;
@@ -46,12 +52,56 @@ class OAuthToken {
   }
 }
 
-class twitterOAuthSignatureMethod_HMAC_SHA1 extends OAuthSignatureMethod_HMAC_SHA1 {/*{{{*/
-  function get_name() {/*{{{*/
+/**
+ * A class for implementing a Signature Method
+ * See section 9 ("Signing Requests") in the spec
+ */
+abstract class OAuthSignatureMethod {
+  /**
+   * Needs to return the name of the Signature Method (ie HMAC-SHA1)
+   * @return string
+   */
+  abstract public function get_name();
+
+  /**
+   * Build up the signature
+   * NOTE: The output of this function MUST NOT be urlencoded.
+   * the encoding is handled in OAuthRequest when the final
+   * request is serialized
+   * @param OAuthRequest $request
+   * @param OAuthConsumer $consumer
+   * @param OAuthToken $token
+   * @return string
+   */
+  abstract public function build_signature($request, $consumer, $token);
+
+  /**
+   * Verifies that a given signature is correct
+   * @param OAuthRequest $request
+   * @param OAuthConsumer $consumer
+   * @param OAuthToken $token
+   * @param string $signature
+   * @return bool
+   */
+  public function check_signature($request, $consumer, $token, $signature) {
+    $built = $this->build_signature($request, $consumer, $token);
+    return $built == $signature;
+  }
+}
+
+/**
+ * The HMAC-SHA1 signature method uses the HMAC-SHA1 signature algorithm as defined in [RFC2104] 
+ * where the Signature Base String is the text and the key is the concatenated values (each first 
+ * encoded per Parameter Encoding) of the Consumer Secret and Token Secret, separated by an '&' 
+ * character (ASCII code 38) even if empty.
+ *   - Chapter 9.2 ("HMAC-SHA1")
+ */
+class OAuthSignatureMethod_HMAC_SHA1 extends OAuthSignatureMethod {
+  function get_name() {
     return "HMAC-SHA1";
-  }/*}}}*/
+  }
 
-  public function build_signature($request, $consumer, $token) {/*{{{*/
+  public function build_signature($request, $consumer, $token) {
     $base_string = $request->get_signature_base_string();
     $request->base_string = $base_string;
 
@@ -63,16 +113,111 @@ class twitterOAuthSignatureMethod_HMAC_SHA1 extends OAuthSignatureMethod_HMAC_SH
     $key_parts = OAuthUtil::urlencode_rfc3986($key_parts);
     $key = implode('&', $key_parts);
 
-    return base64_encode( hash_hmac('sha1', $base_string, $key, true));
-  }/*}}}*/
+    return base64_encode(hash_hmac('sha1', $base_string, $key, true));
+  }
+}
 
-  public function check_signature(&$request, $consumer, $token, $signature) {
-    $built = $this->build_signature($request, $consumer, $token);
-    return $built == $signature;
+/**
+ * The PLAINTEXT method does not provide any security protection and SHOULD only be used 
+ * over a secure channel such as HTTPS. It does not use the Signature Base String.
+ *   - Chapter 9.4 ("PLAINTEXT")
+ */
+class OAuthSignatureMethod_PLAINTEXT extends OAuthSignatureMethod {
+  public function get_name() {
+    return "PLAINTEXT";
+  }
+
+  /**
+   * oauth_signature is set to the concatenated encoded values of the Consumer Secret and 
+   * Token Secret, separated by a '&' character (ASCII code 38), even if either secret is 
+   * empty. The result MUST be encoded again.
+   *   - Chapter 9.4.1 ("Generating Signatures")
+   *
+   * Please note that the second encoding MUST NOT happen in the SignatureMethod, as
+   * OAuthRequest handles this!
+   */
+  public function build_signature($request, $consumer, $token) {
+    $key_parts = array(
+      $consumer->secret,
+      ($token) ? $token->secret : ""
+    );
+
+    $key_parts = OAuthUtil::urlencode_rfc3986($key_parts);
+    $key = implode('&', $key_parts);
+    $request->base_string = $key;
+
+    return $key;
   }
-}/*}}}*/
+}
+
+/**
+ * The RSA-SHA1 signature method uses the RSASSA-PKCS1-v1_5 signature algorithm as defined in 
+ * [RFC3447] section 8.2 (more simply known as PKCS#1), using SHA-1 as the hash function for 
+ * EMSA-PKCS1-v1_5. It is assumed that the Consumer has provided its RSA public key in a 
+ * verified way to the Service Provider, in a manner which is beyond the scope of this 
+ * specification.
+ *   - Chapter 9.3 ("RSA-SHA1")
+ */
+abstract class OAuthSignatureMethod_RSA_SHA1 extends OAuthSignatureMethod {
+  public function get_name() {
+    return "RSA-SHA1";
+  }
+
+  // Up to the SP to implement this lookup of keys. Possible ideas are:
+  // (1) do a lookup in a table of trusted certs keyed off of consumer
+  // (2) fetch via http using a url provided by the requester
+  // (3) some sort of specific discovery code based on request
+  //
+  // Either way should return a string representation of the certificate
+  protected abstract function fetch_public_cert(&$request);
+
+  // Up to the SP to implement this lookup of keys. Possible ideas are:
+  // (1) do a lookup in a table of trusted certs keyed off of consumer
+  //
+  // Either way should return a string representation of the certificate
+  protected abstract function fetch_private_cert(&$request);
+
+  public function build_signature($request, $consumer, $token) {
+    $base_string = $request->get_signature_base_string();
+    $request->base_string = $base_string;
+
+    // Fetch the private key cert based on the request
+    $cert = $this->fetch_private_cert($request);
+
+    // Pull the private key ID from the certificate
+    $privatekeyid = openssl_get_privatekey($cert);
+
+    // Sign using the key
+    $ok = openssl_sign($base_string, $signature, $privatekeyid);
+
+    // Release the key resource
+    openssl_free_key($privatekeyid);
+
+    return base64_encode($signature);
+  }
+
+  public function check_signature($request, $consumer, $token, $signature) {
+    $decoded_sig = base64_decode($signature);
+
+    $base_string = $request->get_signature_base_string();
+
+    // Fetch the public key cert based on the request
+    $cert = $this->fetch_public_cert($request);
+
+    // Pull the public key ID from the certificate
+    $publickeyid = openssl_get_publickey($cert);
 
-class twitterOAuthRequest extends OAuthRequest {
+    // Check the computed signature against the one passed in the query
+    $ok = openssl_verify($base_string, $decoded_sig, $publickeyid);
+
+    // Release the key resource
+    openssl_free_key($publickeyid);
+
+    return $ok == 1;
+  }
+}
+
+class OAuthRequest {
   private $parameters;
   private $http_method;
   private $http_url;
@@ -138,7 +283,7 @@ class twitterOAuthRequest extends OAuthRequest {
 
     }
 
-    return new twitterOAuthRequest($http_method, $http_url, $parameters);
+    return new OAuthRequest($http_method, $http_url, $parameters);
   }
 
   /**
@@ -146,16 +291,16 @@ class twitterOAuthRequest extends OAuthRequest {
    */
   public static function from_consumer_and_token($consumer, $token, $http_method, $http_url, $parameters=NULL) {
     @$parameters or $parameters = array();
-    $defaults = array("oauth_version" => twitterOAuthRequest::$version,
-                      "oauth_nonce" => twitterOAuthRequest::generate_nonce(),
-                      "oauth_timestamp" => twitterOAuthRequest::generate_timestamp(),
+    $defaults = array("oauth_version" => OAuthRequest::$version,
+                      "oauth_nonce" => OAuthRequest::generate_nonce(),
+                      "oauth_timestamp" => OAuthRequest::generate_timestamp(),
                       "oauth_consumer_key" => $consumer->key);
     if ($token)
       $defaults['oauth_token'] = $token->key;
 
     $parameters = array_merge($defaults, $parameters);
 
-    return new twitterOAuthRequest($http_method, $http_url, $parameters);
+    return new OAuthRequest($http_method, $http_url, $parameters);
   }
 
   public function set_parameter($name, $value, $allow_duplicates = true) {
@@ -333,6 +478,217 @@ class twitterOAuthRequest extends OAuthRequest {
   }
 }
 
+class OAuthServer {
+  protected $timestamp_threshold = 300; // in seconds, five minutes
+  protected $version = '1.0';             // hi blaine
+  protected $signature_methods = array();
+
+  protected $data_store;
+
+  function __construct($data_store) {
+    $this->data_store = $data_store;
+  }
+
+  public function add_signature_method($signature_method) {
+    $this->signature_methods[$signature_method->get_name()] =
+      $signature_method;
+  }
+
+  // high level functions
+
+  /**
+   * process a request_token request
+   * returns the request token on success
+   */
+  public function fetch_request_token(&$request) {
+    $this->get_version($request);
+
+    $consumer = $this->get_consumer($request);
+
+    // no token required for the initial token request
+    $token = NULL;
+
+    $this->check_signature($request, $consumer, $token);
+
+    // Rev A change
+    $callback = $request->get_parameter('oauth_callback');
+    $new_token = $this->data_store->new_request_token($consumer, $callback);
+
+    return $new_token;
+  }
+
+  /**
+   * process an access_token request
+   * returns the access token on success
+   */
+  public function fetch_access_token(&$request) {
+    $this->get_version($request);
+
+    $consumer = $this->get_consumer($request);
+
+    // requires authorized request token
+    $token = $this->get_token($request, $consumer, "request");
+
+    $this->check_signature($request, $consumer, $token);
+
+    // Rev A change
+    $verifier = $request->get_parameter('oauth_verifier');
+    $new_token = $this->data_store->new_access_token($token, $consumer, $verifier);
+
+    return $new_token;
+  }
+
+  /**
+   * verify an api call, checks all the parameters
+   */
+  public function verify_request(&$request) {
+    $this->get_version($request);
+    $consumer = $this->get_consumer($request);
+    $token = $this->get_token($request, $consumer, "access");
+    $this->check_signature($request, $consumer, $token);
+    return array($consumer, $token);
+  }
+
+  // Internals from here
+  /**
+   * version 1
+   */
+  private function get_version(&$request) {
+    $version = $request->get_parameter("oauth_version");
+    if (!$version) {
+      // Service Providers MUST assume the protocol version to be 1.0 if this parameter is not present. 
+      // Chapter 7.0 ("Accessing Protected Ressources")
+      $version = '1.0';
+    }
+    if ($version !== $this->version) {
+      throw new OAuthException("OAuth version '$version' not supported");
+    }
+    return $version;
+  }
+
+  /**
+   * figure out the signature with some defaults
+   */
+  private function get_signature_method(&$request) {
+    $signature_method =
+        @$request->get_parameter("oauth_signature_method");
+
+    if (!$signature_method) {
+      // According to chapter 7 ("Accessing Protected Ressources") the signature-method
+      // parameter is required, and we can't just fallback to PLAINTEXT
+      throw new OAuthException('No signature method parameter. This parameter is required');
+    }
+
+    if (!in_array($signature_method,
+                  array_keys($this->signature_methods))) {
+      throw new OAuthException(
+        "Signature method '$signature_method' not supported " .
+        "try one of the following: " .
+        implode(", ", array_keys($this->signature_methods))
+      );
+    }
+    return $this->signature_methods[$signature_method];
+  }
+
+  /**
+   * try to find the consumer for the provided request's consumer key
+   */
+  private function get_consumer(&$request) {
+    $consumer_key = @$request->get_parameter("oauth_consumer_key");
+    if (!$consumer_key) {
+      throw new OAuthException("Invalid consumer key");
+    }
+
+    $consumer = $this->data_store->lookup_consumer($consumer_key);
+    if (!$consumer) {
+      throw new OAuthException("Invalid consumer");
+    }
+
+    return $consumer;
+  }
+
+  /**
+   * try to find the token for the provided request's token key
+   */
+  private function get_token(&$request, $consumer, $token_type="access") {
+    $token_field = @$request->get_parameter('oauth_token');
+    $token = $this->data_store->lookup_token(
+      $consumer, $token_type, $token_field
+    );
+    if (!$token) {
+      throw new OAuthException("Invalid $token_type token: $token_field");
+    }
+    return $token;
+  }
+
+  /**
+   * all-in-one function to check the signature on a request
+   * should guess the signature method appropriately
+   */
+  private function check_signature(&$request, $consumer, $token) {
+    // this should probably be in a different method
+    $timestamp = @$request->get_parameter('oauth_timestamp');
+    $nonce = @$request->get_parameter('oauth_nonce');
+
+    $this->check_timestamp($timestamp);
+    $this->check_nonce($consumer, $token, $nonce, $timestamp);
+
+    $signature_method = $this->get_signature_method($request);
+
+    $signature = $request->get_parameter('oauth_signature');
+    $valid_sig = $signature_method->check_signature(
+      $request,
+      $consumer,
+      $token,
+      $signature
+    );
+
+    if (!$valid_sig) {
+      throw new OAuthException("Invalid signature");
+    }
+  }
+
+  /**
+   * check that the timestamp is new enough
+   */
+  private function check_timestamp($timestamp) {
+    if( ! $timestamp )
+      throw new OAuthException(
+        'Missing timestamp parameter. The parameter is required'
+      );
+    
+    // verify that timestamp is recentish
+    $now = time();
+    if (abs($now - $timestamp) > $this->timestamp_threshold) {
+      throw new OAuthException(
+        "Expired timestamp, yours $timestamp, ours $now"
+      );
+    }
+  }
+
+  /**
+   * check that the nonce is not repeated
+   */
+  private function check_nonce($consumer, $token, $nonce, $timestamp) {
+    if( ! $nonce )
+      throw new OAuthException(
+        'Missing nonce parameter. The parameter is required'
+      );
+
+    // verify that the nonce is uniqueish
+    $found = $this->data_store->lookup_nonce(
+      $consumer,
+      $token,
+      $nonce,
+      $timestamp
+    );
+    if ($found) {
+      throw new OAuthException("Nonce already used: $nonce");
+    }
+  }
+
+}
+
 class OAuthDataStore {
   function lookup_consumer($consumer_key) {
     // implement me
@@ -514,5 +870,3 @@ class OAuthUtil {
     return implode('&', $pairs);
   }
 }
-
-?>
diff --git a/mod/twitter_api/vendors/twitteroauth/README b/mod/twitter_api/vendors/twitteroauth/README
index 33cb91f21..c9a17ce4b 100644
--- a/mod/twitter_api/vendors/twitteroauth/README
+++ b/mod/twitter_api/vendors/twitteroauth/README
@@ -1,7 +1,114 @@
-Abraham Williams | abraham@poseurte.ch | http://abrah.am | @abraham
+TwitterOAuth
+------------
 
-The first PHP library for working with Twitter's OAuth API.
+PHP library for working with Twitter's OAuth API.
 
-Documentation: http://wiki.github.com/abraham/twitteroauth/documentation 
-Source: http://github.com/abraham/twitteroauth
-Twitter: http://apiwiki.twitter.com
+Flow Overview
+=============
+
+1. Build TwitterOAuth object using client credentials.
+2. Request temporary credentials from Twitter.
+3. Build authorize URL for Twitter.
+4. Redirect user to authorize URL.
+5. User authorizes access and returns from Twitter.
+6. Rebuild TwitterOAuth object with client credentials and temporary credentials.
+7. Get token credentials from Twitter.
+8. Rebuild TwitterOAuth object with client credentials and token credentials.
+9. Query Twitter API.
+
+Terminology
+===========
+
+The terminology has changed since 0.1.x to better match the draft-hammer-oauth IETF
+RFC. You can read that at http://tools.ietf.org/html/draft-hammer-oauth. Some of the
+terms will differ from those Twitter uses as well.
+
+client credentials - Consumer key/secret you get when registering an app with Twitter.
+temporary credentials - Previously known as the request token.
+token credentials - Previously known as the access token.
+
+Parameters
+==========
+
+There are a number of parameters you can modify after creating a TwitterOAuth object.
+
+Switch an existing TwitterOAuth install to use version 1.1 of the API.
+
+    $connection->$host = "https://api.twitter.com/1.1/";
+
+Custom useragent.
+
+    $connection->useragent = 'Custom useragent string';
+
+Verify Twitters SSL certificate.
+
+    $connection->ssl_verifypeer = TRUE;
+
+There are several more you can find in TwitterOAuth.php.
+
+Extended flow using example code
+================================
+
+To use TwitterOAuth with the Twitter API you need *TwitterOAuth.php*, *OAuth.php* and
+client credentials. You can get client credentials by registering your application at
+[dev.twitter.com/apps](https://dev.twitter.com/apps).
+
+Users start out on connect.php which displays the "Sign in with Twitter" image hyperlinked
+to redirect.php. This button should be displayed on your homepage in your login section. The
+client credentials are saved in config.php as `CONSUMER_KEY` and `CONSUMER_SECRET`. You can
+save a static callback URL in the app settings page, in the config file or use a dynamic
+callback URL later in step 2. In example use https://example.com/callback.php.
+
+1) When a user lands on redirect.php we build a new TwitterOAuth object using the client credentials.
+If you have your own configuration method feel free to use it instead of config.php.
+
+    $connection = new TwitterOAuth(CONSUMER_KEY, CONSUMER_SECRET); // Use config.php client credentials
+    $connection = new TwitterOAuth('abc890', '123xyz');
+
+2) Using the built $connection object you will ask Twitter for temporary credentials. The `oauth_callback` value is required.
+
+    $temporary_credentials = $connection->getRequestToken(OAUTH_CALLBACK); // Use config.php callback URL.
+
+3) Now that we have temporary credentials the user has to go to Twitter and authorize the app
+to access and updates their data. You can also pass a second parameter of FALSE to not use [Sign
+in with Twitter](https://dev.twitter.com/docs/auth/sign-twitter).
+
+    $redirect_url = $connection->getAuthorizeURL($temporary_credentials); // Use Sign in with Twitter
+    $redirect_url = $connection->getAuthorizeURL($temporary_credentials, FALSE);
+
+4) You will now have a Twitter URL that you must send the user to.
+
+    https://api.twitter.com/oauth/authenticate?oauth_token=xyz123
+
+5) The user is now on twitter.com and may have to login. Once authenticated with Twitter they will
+will either have to click on allow/deny, or will be automatically redirected back to the callback.
+
+6) Now that the user has returned to callback.php and allowed access we need to build a new
+TwitterOAuth object using the temporary credentials.
+
+    $connection = new TwitterOAuth(CONSUMER_KEY, CONSUMER_SECRET, $_SESSION['oauth_token'],
+    $_SESSION['oauth_token_secret']);
+
+7) Now we ask Twitter for long lasting token credentials. These are specific to the application
+and user and will act like password to make future requests. Normally the token credentials would
+get saved in your database but for this example we are just using sessions.
+
+    $token_credentials = $connection->getAccessToken($_REQUEST['oauth_verifier']);
+
+8) With the token credentials we build a new TwitterOAuth object.
+
+    $connection = new TwitterOAuth(CONSUMER_KEY, CONSUMER_SECRET, $token_credentials['oauth_token'],
+    $token_credentials['oauth_token_secret']);
+
+9) And finally we can make requests authenticated as the user. You can GET, POST, and DELETE API
+methods. Directly copy the path from the API documentation and add an array of any parameter
+you wish to include for the API method such as curser or in_reply_to_status_id.
+
+    $account = $connection->get('account/verify_credentials');
+    $status = $connection->post('statuses/update', array('status' => 'Text of status here', 'in_reply_to_status_id' => 123456));
+    $status = $connection->delete('statuses/destroy/12345');
+
+Contributors
+============
+
+* [Abraham Williams](https://twitter.com/abraham) - Main developer, current maintainer.
diff --git a/mod/twitter_api/vendors/twitteroauth/twitterOAuth.php b/mod/twitter_api/vendors/twitteroauth/twitterOAuth.php
index f36e6158d..4c2447c46 100644
--- a/mod/twitter_api/vendors/twitteroauth/twitterOAuth.php
+++ b/mod/twitter_api/vendors/twitteroauth/twitterOAuth.php
@@ -57,7 +57,7 @@ class TwitterOAuth {
    * construct TwitterOAuth object
    */
   function __construct($consumer_key, $consumer_secret, $oauth_token = NULL, $oauth_token_secret = NULL) {
-    $this->sha1_method = new twitterOAuthSignatureMethod_HMAC_SHA1();
+    $this->sha1_method = new OAuthSignatureMethod_HMAC_SHA1();
     $this->consumer = new OAuthConsumer($consumer_key, $consumer_secret);
     if (!empty($oauth_token) && !empty($oauth_token_secret)) {
       $this->token = new OAuthConsumer($oauth_token, $oauth_token_secret);
@@ -72,11 +72,9 @@ class TwitterOAuth {
    *
    * @returns a key/value array containing oauth_token and oauth_token_secret
    */
-  function getRequestToken($oauth_callback = NULL) {
+  function getRequestToken($oauth_callback) {
     $parameters = array();
-    if (!empty($oauth_callback)) {
-      $parameters['oauth_callback'] = $oauth_callback;
-    } 
+    $parameters['oauth_callback'] = $oauth_callback; 
     $request = $this->oAuthRequest($this->requestTokenURL(), 'GET', $parameters);
     $token = OAuthUtil::parse_parameters($request);
     $this->token = new OAuthConsumer($token['oauth_token'], $token['oauth_token_secret']);
@@ -108,11 +106,9 @@ class TwitterOAuth {
    *                "user_id" => "9436992",
    *                "screen_name" => "abraham")
    */
-  function getAccessToken($oauth_verifier = FALSE) {
+  function getAccessToken($oauth_verifier) {
     $parameters = array();
-    if (!empty($oauth_verifier)) {
-      $parameters['oauth_verifier'] = $oauth_verifier;
-    }
+    $parameters['oauth_verifier'] = $oauth_verifier;
     $request = $this->oAuthRequest($this->accessTokenURL(), 'GET', $parameters);
     $token = OAuthUtil::parse_parameters($request);
     $this->token = new OAuthConsumer($token['oauth_token'], $token['oauth_token_secret']);
@@ -179,7 +175,7 @@ class TwitterOAuth {
     if (strrpos($url, 'https://') !== 0 && strrpos($url, 'http://') !== 0) {
       $url = "{$this->host}{$url}.{$this->format}";
     }
-    $request = twitterOAuthRequest::from_consumer_and_token($this->consumer, $this->token, $method, $url, $parameters);
+    $request = OAuthRequest::from_consumer_and_token($this->consumer, $this->token, $method, $url, $parameters);
     $request->sign_request($this->sha1_method, $this->consumer, $this->token);
     switch ($method) {
     case 'GET':