blackberry.com
BlackBerry Dynamics
Runtime library for iOS applications
from the application developer portal
Public Member Functions | Properties

GDUtility Class Reference

BlackBerry Dynamics authentication token request. More...

#import <GDUtility.h>

List of all members.

Public Member Functions

Properties


Detailed Description

The BlackBerry Dynamics authentication token mechanism enables applications to utilize the user identification that takes place during BlackBerry Dynamics authorization processing. This enables an application server at the enterprise to authenticate the user without the need for entry of any additional credentials at the device or desktop.

See below for an overall description of the BlackBerry Dynamics authentication token mechanism. This class includes the programming interface for requesting tokens.

See also:
authorize (GDiOS) for more details of BlackBerry Dynamics authorization processing.
Authentication Token Back-End API

BlackBerry Dynamics Authentication Token Mechanism

The BlackBerry Dynamics platform includes rigorous authentication of the end user. This is used when, for example, identifying whether the user is entitled to run the current application, and when applying security policies.

The BlackBerry Dynamics Authentication Token (BlackBerry Dynamics auth) mechanism enables applications to take advantage of the authentication processes of the platform.

BlackBerry Dynamics auth tokens can be requested by the application on the device or desktop. A token will only be issued if authorization processing has completed, and the end user's identity has been authenticated.

Once a token has been issued, the application can send the token to an application server at the back end. The token can then be checked by the application server, using a verification service provided by the BlackBerry Dynamics infrastructure.

The sequence of programming interfaces used in BlackBerry Dynamics auth is as follows.

  1. The mobile application calls getGDAuthToken:serverName to request a token.
  2. All being well, a token is issued and the onGDAuthTokenSuccess callback is invoked and passed the new token.
  3. The application sends the token to the application server, using an HTTP request, socket, or other method. In the same communication, the application sends the email address or other end user identifier for which it is activated as a BlackBerry Dynamics application.
  4. The application server checks that the token is valid by calling the verification service in the Authentication Token Back-End API, hosted by an enterprise BlackBerry Dynamics server. (The server could be a BlackBerry Proxy or Good Proxy instance.)
  5. The response from the verification service includes the end user identifier, if the token is valid. The application server can check that the value from the verification service is the same as that originally sent by the mobile application.

This sequence validates the end user's identity, and the application server can therefore grant access to resources and other permissions.

Calling the verification service doesn't cause the token to be consumed.

Note that a BlackBerry Dynamics application can obtain the identifier of the end user from the GDAppConfigKeyUserId value in the collection returned by the getApplicationConfig (GDiOS) function.

Challenge Strings

A challenge string can be included in a BlackBerry Dynamics auth token request. The same challenge string will then be provided to the application server, in the response from the verification service.

The challenge string could have a number of uses for application developers. A typical usage could be to tie an instance of authentication to a previous access request, as follows:

  1. A mobile application attempts to access a resource on an application server.
  2. The application server generates a random challenge string.
  3. The application server responds to the mobile application with a denial of access message that includes the random challenge string.
  4. The mobile application requests a BlackBerry Dynamics auth token, and passes the value from the denial of access message as the challenge string.
  5. The mobile application again attempts to access the resource on the application server, but this time includes the BlackBerry Dynamics auth token in the request.
  6. The application server sends the token to the verification service, which responds that the token is valid. The response includes the challenge string.
  7. The application server checks that the challenge string from the verification service is the same as the random challenge string initially sent to the mobile application in the denial of access message.

In the above, a new random challenge string is generated on every resource access attempt. This has the effect of making the BlackBerry Dynamics auth tokens one-use. A more advanced algorithm might be to store the token and challenge string in the server, as a session identifier. To end a session, the server could delete the stored token and challenge string, effectively forcing the application to generate a new token, based on a new challenge string, when it next connected.

The verification service provides the challenge string to the application server in an HTTP header, which limits the character set that can be utilized safely. All letters and numerals in the ASCII range 32 to 126 can be utilized safely. Use of other characters isn't supported.


Member Function Documentation

- (void) getGDAuthToken: (NSString *)  challenge
serverName: (NSString *)  serverName 

Call this function to request a new BlackBerry Dynamics authentication token. Pass the challenge string and server name as parameters.

See under BlackBerry Dynamics Authentication Token Mechanism, above, for background on tokens and the challenge string.

This function requests a BlackBerry Dynamics authentication token from the BlackBerry Dynamics runtime. The runtime might connect to the BlackBerry Dynamics infrastructure installed at the enterprise in order to service the request.

The request is asynchronous. If the request succeeds, the token will be passed to the onGDAuthTokenSuccess callback in the delegate. If the attempt fails, an error will be passed to the onGDAuthTokenFailure callback in the delegate instead.

The delegate property must be set before this function is called.

Parameters:
challengeNSString containing the challenge string for the token. The challenge string can be empty.
serverNameNSString containing additional identification, by convention the fully qualified domain name of the application server for which a token is being requested. Whatever value is passed here will also be returned to the server as part of the token validation response.

Property Documentation

- (id<GDAuthTokenDelegate>) gdAuthDelegate [read, write, assign]

BlackBerry Dynamics authentication token requests are asynchronous. When a request succeeds or fails, a callback in the application code is invoked by the BlackBerry Dynamics runtime.

Set this property to an instance of a class in the application that contains the code for the required callbacks, i.e. a class that implements the GDAuthTokenDelegate protocol.


The documentation for this class was generated from the following file: