On Tue, Sep 28, 2010 at 4:17 PM, Roger Kitain
<roger.kitain@oracle.com> wrote:
Comments inline..
On 9/28/10 2:56 PM, Alexander Smirnov wrote:
The #2 approach is already here, it's JSF view state field. It would be
make even stronger by some random string added to its value, but that
doesn't require any change in spec; the format of state field is up to
implementation.
random value.
The #1 is also available as custom view parameter, but we can make it
more convinient as implicit view parameter and metadata control
included in all ( or selected ) navigation links and views. It would
leverage already existing JSF 2.0 features. As well as view parameters
processed in the separate ExternalContext method, they are portlet-safe.
Hmm... They are probably many ways to slice and dice this problem.
I think we were looking for a more automatic solution then having to introduce
more burden on page authors or application developers.
On 09/21/2010 10:15 AM, Roger Kitain wrote:
There are two proposals for enhancing CSRF attacks in JSF. We need to
pick one.
Proposal 1: Form Action URL Approach (Approach provided by Kito Mann)
This approach does the following: - Token is generated on the
server consisting (minimally) of a randomly generated "secret key
(stored in session).
- ViewHandler.getActionURL method must include the token parameter
named "javax.faces.Token", and whose value is the token value.
- At render time this token will be included in Form's action URL -
and it will be
posted back to the server.
- Restore View Phase processing compares the incoming token request
parameter value
with the token value generated from the secret key in the session.
Spec Document Modifications:
Section 7.5.1:
getActionURL:
"The URL must contain the parameter constant defined by
ResponseStateManager.VIEW_TOKEN_PARAM
The value of this parameter must be a cryptographically produced value
minimally consisting
of a "secret key". The "secret key" is a random generated value that was
stored in the session
(preferably around session creation time). Implementations may also
choose to combine other
values with the secret key to produce a more complex token."
Section 2.2.1
"Verify the "javax.faces.Token" request parameter value is the same as
the token value generated
from the "secret key" stored in the session. If the values do not
match, throw a meaningful
exception."
Proposal 2: Form Hidden Field Approach
This approach is similar to Approach 1, except a Form hidden field
"javax.faces.Token"
is used instead of appending to the Form's Action URL.
Spec Document Modifications:
Standard RenderKit Docs
- Form Rendering
"Render a hidden field named "javax.faces.Token" using the
ResponseStateManager.VIEW_TOKEN_PARAM
constant. The value of this hidden field is a cryptographically
produced value that must at least
consist of a "secret key". The "secret key" is a random generated
value that was stored in the
session (preferably around session creation time). Implementations may
also choose to combine
other values with the secret key to produce a more complex token."
Specification Document
Section 2.2.1
"Verify the "javax.faces.Token" request parameter value is the same as
the token value generated
from the "secret key" stored in the session. If the values do not
match, throw a FacesException.
For both approaches see:
[1]
https://javaserverfaces-spec-public.dev.java.net/issues/show_bug.cgi?id=869
Look at the two latest change bundles attached to the issue.
Please review by COB Friday as we have no time left for 2.1.
Kudos to Kito Mann for helping out with the implementation.
-roger