An introduction to OAuth

1. A (20 minutes)
introduction to
Oauth.

2. Roadmap
 Defining Oauth
 Why Oauth?
 Background
 Terminology
 Workflow
 Live Example
 References
 Q&A

3. Defining Oauth
”Oauth provides a method for users to
grant third-party access to their resources
without sharing their passwords. It also
passwords
provides a way to grant limited access (in
scope, duration, etc …)”

4. Why Oauth?
 Traditional client-server authentication model.
Client - Photos
- Wall
- Friends
Credential
Client - Tweets.
- Tags
Application - Position
Credential
Client
- Job
- Expertise
- CV
Credential

5. Why Oauth?
 Issues with traditional client-service auth model
 Users share their credentials (password) with
the application for each service
 Application needs as many credentials as
services
 Once the application get the user password
there is no way to invalid the access to the
user's resources … unless user changes his
password
 Application has the same privileges as the user.

6. Background
 Based on well-established practices of many
propietary industry protocols.
 Google AuthSub
 Yahoo BBAuth
 Flickr API
 Focused on website services but also desktop
applications, mobile devices or set-top boxes.

7. Background
 OpenID 2006 Blaine Cook descentralized
digital idetification standard.
 OpenAuth 2006 Chris Messina no sharing
password and login agnostic.
 OpenAuth Google 2007
 AOL's implements OpenAuth protocol 2007
 OauthCore 1.0 Revision 2009
 Oauth Core 1.0 RFC 2010
 Present-Future … OAuth 2.0 Draft
http://tools.ietf.org/html/draft-ietf-oauth-v2-26

8. Terminology
consumer Service provider
user

9. Workflow
Goal: Print on demand our last
Service provider
Summer photos through a web
application that we previously
uploaded to Facebook.
Step 1 –User access to Print
Service.
Step 2 – Print Service gives you
the choice to access to Facebook
to get your photos.
Step 3 – You were redirected to
Facebook login page
Step 4 – Once you are logged in
you authorized the Print Service
to access your photos on
Facebook.
Step 5 – You are redirected to
the Print Service where you
access your photos. Consumer User

10. Workflow
 Redirection-based authorization.
Credentials types.
 Get temporary credentials
 Obtain authorization from the resources
owner.
 Get token credentials (request token +
secret).

11. Live Example
 Give authorization to Wordpress to post on your
Facebook's wall and your Twitter account.

12. References
 Official page. http://oauth.net/
 Beginner's guide to Oauth
http://oauth.net/documentation/getting-started/
 Google Oauth
https://developers.google.com/accounts/
 Getting Started with OAuth 2.0 by Ryan Boyd
 Programming Social Applications: Building Viral
Experiences with OpenSocial, OAuth, OpenID,
and Distributed Web Frameworks by Jonathan
LeBlanc

13. Q&A