1 files changed, 50 insertions, 56 deletions

diff --git a/engine/lib/pam.php b/engine/lib/pam.php
index 91bf63f7c..1c9c3bfe1 100644
--- a/engine/lib/pam.php
+++ b/engine/lib/pam.php
@@ -1,32 +1,58 @@
 <?php
 /**
- * Elgg PAM library
- * Contains functions for managing authentication using various arbitrary methods
+ * Elgg Simple PAM library
+ * Contains functions for managing authentication.
+ * This is not a full implementation of PAM. It supports a single facility
+ * (authentication) and allows multiple policies (user authentication is the
+ * default). There are two control flags possible for each module: sufficient
+ * or required. The entire chain for a policy is processed (or until a
+ * required module fails). A module fails by returning false or throwing an
+ * exception. The order that modules are processed is determined by the order
+ * they are registered. For an example of a PAM, see pam_auth_userpass() in
+ * sessions.php.
  *
- * @package Elgg
- * @subpackage Core
- * @author Curverider Ltd
- * @link http://elgg.org/
+ * For more information on PAMs see:
+ * http://www.freebsd.org/doc/en/articles/pam/index.html
+ *
+ * @see ElggPAM
+ *
+ * @package Elgg.Core
+ * @subpackage Authentication.PAM
  */
 
+global $_PAM_HANDLERS;
 $_PAM_HANDLERS = array();
-$_PAM_HANDLERS_MSG = array();
 
 /**
  * Register a PAM handler.
  *
- * @param string $handler The handler function in the format
- * 		pam_handler($credentials = NULL);
- * @param string $importance The importance - "sufficient" or "required"
+ * A PAM handler should return true if the authentication attempt passed. For a
+ * failure, return false or throw an exception. Returning nothing indicates that
+ * the handler wants to be skipped.
+ *
+ * Note, $handler must be string callback (not an array/Closure).
+ *
+ * @param string $handler    Callable global handler function in the format ()
+ * 		                     pam_handler($credentials = NULL);
+ * @param string $importance The importance - "sufficient" (default) or "required"
+ * @param string $policy     The policy type, default is "user"
+ *
+ * @return bool
  */
-function register_pam_handler($handler, $importance = "sufficient") {
+function register_pam_handler($handler, $importance = "sufficient", $policy = "user") {
 	global $_PAM_HANDLERS;
 
-	if (is_callable($handler)) {
-		$_PAM_HANDLERS[$handler] = new stdClass;
+	// setup array for this type of pam if not already set
+	if (!isset($_PAM_HANDLERS[$policy])) {
+		$_PAM_HANDLERS[$policy] = array();
+	}
+
+	// @todo remove requirement that $handle be a global function
+	if (is_string($handler) && is_callable($handler, true)) {
+		$_PAM_HANDLERS[$policy][$handler] = new stdClass;
 
-		$_PAM_HANDLERS[$handler]->handler = $handler;
-		$_PAM_HANDLERS[$handler]->importance = strtolower($importance);
+		$_PAM_HANDLERS[$policy][$handler]->handler = $handler;
+		$_PAM_HANDLERS[$policy][$handler]->importance = strtolower($importance);
 
 		return true;
 	}
@@ -35,48 +61,16 @@ function register_pam_handler($handler, $importance = "sufficient") {
 }
 
 /**
- * Attempt to authenticate.
- * This function will go through all registered PAM handlers to see if a user can be authorised.
+ * Unregisters a PAM handler.
  *
- * If $credentials are provided the PAM handler should authenticate using the provided credentials, if
- * not then credentials should be prompted for or otherwise retrieved (eg from the HTTP header or $_SESSION).
+ * @param string $handler The PAM handler function name
+ * @param string $policy  The policy type, default is "user"
  *
- * @param mixed $credentials Mixed PAM handler specific credentials (eg username,password or hmac etc)
- * @return bool true if authenticated, false if not.
+ * @return void
+ * @since 1.7.0
  */
-function pam_authenticate($credentials = NULL) {
-	global $_PAM_HANDLERS, $_PAM_HANDLERS_MSG;
-
-	$authenticated = false;
-
-	foreach ($_PAM_HANDLERS as $k => $v) {
-		$handler = $v->handler;
-		$importance = $v->importance;
-
-		try {
-			// Execute the handler
-			if ($handler($credentials)) {
-				// Explicitly returned true
-				$_PAM_HANDLERS_MSG[$k] = "Authenticated!";
-
-				$authenticated = true;
-			} else {
-				$_PAM_HANDLERS_MSG[$k] = "Not Authenticated.";
-
-				// If this is required then abort.
-				if ($importance == 'required') {
-					return false;
-				}
-			}
-		} catch (Exception $e) {
-			$_PAM_HANDLERS_MSG[$k] = "$e";
-
-			// If this is required then abort.
-			if ($importance == 'required') {
-				return false;
-			}
-		}
-	}
+function unregister_pam_handler($handler, $policy = "user") {
+	global $_PAM_HANDLERS;
 
-	return $authenticated;
-}
\ No newline at end of file
+	unset($_PAM_HANDLERS[$policy][$handler]);
+}