For our application, we would like to prevent users
from requesting application resources directly.
E.g. browsing to http://localhost/app/method.do?id=5&type=3
instead of actually clicking on a link that the application provides.
You can do that without any code writing.
You must only install an application firewall in front of your Web application.
The application firewall must have a session manager feature to enable or
disable browsing on a specific page.
This feature is sometimes called "Dynamic White Page".
When actived, only specific URLs (start pages defined by administrator) can be
used to enter in the web app.
Best Regards,
Roberto GABERGI (mailto:roberto.gabergi@axiliance.com)
AXILIANCE - http://www.axiliance.com
Web Application Firewall, Citrix ICA Security and Web Single Sign-On
-----Message d'origine-----
De : Kevin Conaway [mailto:kevin.conaway@gmail.com]
Envoyé : mardi 1 mars 2005 16:20
À : webappsec@securityfocus.com
Objet : Preventing direct URL access in a J2EE environment
For our application, we would like to prevent users from requesting application
resources directly. E.g. browsing to
http://localhost/app/method.do?id=5&type=3 instead of actually clicking on a
link that the application provides.
We would like to do this without a major impact on our code. I was thinking of
using the following scenario:
- Currently we have tag libraries that help build all our URLS. These tag
libraries would be modified to include a strong cryptographic token that is
unique to each URL/User combination. - The token/URL combination would be
stored in the application context for a pre-determined amount of time.
- Next, we would use a Servlet filter to intercept the URL. First, deny URLS
requested without tokens. If a token is passed, verify that matches the token
stored in the application context for the requested URL.
For the token, I was considering using SecureRandom to generate a random number
and compute a hash of the random number and the URI being requested. This
would be stored along with with URI and the user Id.
Could anyone point out any pitfalls I need to be aware of, or if I'm going
about things the wrong way?
Thanks
Kevin
