issrg.security
Class GUICallbackHandler

java.lang.Object
  issrg.security.GUICallbackHandler

All Implemented Interfaces:

javax.security.auth.callback.CallbackHandler

public class GUICallbackHandler
extends java.lang.Object
implements javax.security.auth.callback.CallbackHandler

This is a CallbackHandler that can display a dialog per each invocation of handle method. Therefore, it is possible to display a single dialog to collect all the necessary information in one go, or multiple dialogs can be displayed.

See JAAS documentation on details of the role of CallbackHandler in authentication process.

You will notice that PERMIS core does not use JAAS at all (no need to authenticate users - they are already authenticated). It is PERMIS utilities and tools that use the Callbacks to get the password to the PKCS#12 files or Java keystores. Note that they do not use the Callbacks in the purely JAAS way, since ultimately the access to the private keys is needed, and not just authentication of users is required; but the use of JAAS classes helps to build tools that do not depend on the type of interface available. This specifically caters for GUI-less environments, e.g. application servers.

Constructor Summary

GUICallbackHandler()

Method Summary

void	handle(javax.security.auth.callback.Callback[] callbacks) This is the implementation of the JAAS method to display a number of controls to collect user input, which is used in authentication.
void	setParentFrame(java.awt.Frame pf) This method sets the frame to which the dialogs will be modal.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

GUICallbackHandler

public GUICallbackHandler()

Method Detail

setParentFrame

public void setParentFrame(java.awt.Frame pf)

This method sets the frame to which the dialogs will be modal.

Parameters:

pf - - the parent Frame; all dialogs will be modal to this Frame; if null is specified, then the dialog will be modal to the main window of the application

handle

public void handle(javax.security.auth.callback.Callback[] callbacks)
            throws javax.security.auth.callback.UnsupportedCallbackException

This is the implementation of the JAAS method to display a number of controls to collect user input, which is used in authentication. This method constructs a dialog box with a number of controls, determined by the types of Callbacks, and two control buttons: one to confirm the selections made by the user, one to cancel the dialog (all input is ignored). The dialog box is modal to the Frame set to be parent Frame of this GUICallbackHandler.

Because GUICallbackHandler caters for the specific purpose, it supports only some of the standard Callbacks, and all of the Callbacks defined by PERMIS. The following Callbacks are supported:

• TitleCallback
- a special extension of TextOutputCallback, introduced to create the title of the dialog window; in GUI-less environments you will probably see it as a single line of text output before any other input or output
• TextOutputCallback
- a standard JAAS Callback; a label with the corresponding text is placed on a separate row of the dialog
• FilenameCallback
- a special extension of NameCallback, introduced to help the user select the file by browsing the file system; in GUI-less environments you will probably see a prompt to enter the filename and the default filename will be prompted, and the user will need to type the full filename; the GUI dialog displays a label with the prompt followed by a text input box and a button to pop up a OpenFile dialog to browse the filesystem and select a file
• PasswordCallback
- a standard JAAS Callback; a prompt and a password input box are placed on a separate row in a dialog

Note that each Callback may appear multiple times. For example, it is possible to prompt for multiple shares of the password to be input in the same dialog.

Specified by:

handle in interface javax.security.auth.callback.CallbackHandler

Parameters:

callbacks - - the array of Callbacks, each representing a control for user input, as specified in JAAS framework

Throws:

javax.security.auth.callback.UnsupportedCallbackException - if at least one of the Callbacks is not supported and cannot be displayed

See Also:

setParentFrame(java.awt.Frame)