Console user security policy

* bus/config-parser.c:
(struct PolicyType): Add POLICY_CONSOLE
(struct Element.d.policy): s/gid_or_uid/gid_uid_or_at_console
(start_busconfig_child): Sets up console element when
<policy at_console=""> is encountered in a policy file
(append_rule_from_element): Convert console elements to console
rules.

* bus/policy.c:
(bus_policy_create_client_policy): Add console rules to the client
policy based on if the client is at the console
(bus_policy_append_console_rule): New function for adding a
console rule to a policy
(bus_policy_merge): Handle console rule merging

* dbus/dbus-sysdeps.h: Added the DBUS_CONSOLE_DIR constant
where we check for console user files

* dbus/dbus-sysdeps.c:
(_dbus_file_exists): New function which checks if the given
file exists
(_dbus_user_at_console): New function which does the system
specific process of checking if the user is at the console

* dbus/dbus-userdb.c:
(_dbus_is_console_user): New function converts a UID to user name
and then calls the system specific _dbus_user_at_console to
see if the user is at the console and therefor a console user

1 files changed, 43 insertions, 0 deletions

diff --git a/dbus/dbus-userdb.c b/dbus/dbus-userdb.c
index 1e105b29..833256c5 100644
--- a/dbus/dbus-userdb.c
+++ b/dbus/dbus-userdb.c
@@ -38,6 +38,7 @@ struct DBusUserDatabase
   DBusHashTable *groups; /**< Groups in the database by GID */
   DBusHashTable *users_by_name; /**< Users in the database by name */
   DBusHashTable *groups_by_name; /**< Groups in the database by name */
+
 };
 
 static void
@@ -399,6 +400,48 @@ _dbus_get_user_id (const DBusString  *username,
 }
 
 /**
+ * Checks to see if the UID sent in is the console user
+ *
+ * @param uid UID of person to check 
+ * @param error return location for errors
+ * @returns #TRUE if the UID is the same as the console user and there are no errors
+ */
+dbus_bool_t
+_dbus_is_console_user (dbus_uid_t uid,
+		       DBusError *error)
+{
+
+  DBusUserDatabase *db;
+  const DBusUserInfo *info;
+  DBusString *console_file;
+  dbus_bool_t result = FALSE; 
+
+  _dbus_user_database_lock_system ();
+
+  db = _dbus_user_database_get_system ();
+  if (db == NULL)
+    {
+      dbus_set_error (error, DBUS_ERROR_FAILED, "Could not get system database.");
+      _dbus_user_database_unlock_system ();
+      return FALSE;
+    }
+
+  info = _dbus_user_database_lookup (db, uid, NULL, error);
+
+  if (info == NULL)
+    {
+      _dbus_user_database_unlock_system ();
+       return FALSE;
+    }
+
+  result = _dbus_user_at_console (info->username, error);
+
+  _dbus_user_database_unlock_system ();
+
+  return result;
+}
+
+/**
  * Gets group ID given groupname
  *
  * @param groupname the groupname