Thank you both for your replies.

On 9/2/2011 6:55 AM, Phil Ames wrote:
> On Thu, Sep 1, 2011 at 12:56 AM, Joachim Fritschi 
> <[email protected] <mailto:[email protected]>> wrote:
>
>     Am 31.08.2011 23 <tel:31.08.2011%2023>:30, schrieb Lars Huttar:
>
>         1) When the first unauthenticated request comes in:
>         - give the user a cookie with a unique id (I think this would
>         have to be
>         separate from the CASTGC, but I'm not sure)
>         - store the content of their POST data somewhere, tied to that id.
>
>     Sound like a bad idea because storing post data would be pretty
>     much an invite of an attack in my eyes. LimitRequestBody which is
>     the only Apache setting to limit the size of POSTs to my knowledge
>     is by default unlimited with the addition of the 300s default
>     Timeout? Your idea would allow would allow a pretty easy memory
>     exaustion attack (DoS)
>
>
> Yes, this is primarily why this feature or a variant is not currently 
> implemented.  There are some other possible workarounds, i.e. encode 
> the POST data in the URL and somehow signal back to mod_auth_cas to 
> rewrite the request as such, but I think this is bound to be more 
> complicated, and won't scale to large POST bodies.

That was my thought too.

>
>     In my eyes you should simply adjust your client to the cas setup
>     and make it cas aware:
>
>     1. Do a non POST hit on the webserver (mod_auth_cas protected) and
>     check if your cookie/login is still valid. If not do the normal
>     login and your simple hit will arrive at the server. (doing a dir
>     list or something simple you can think of in terms of server load)
>
>     2. Now you are sure you have a valid login/ticket. Now you
>     transfer you POST data. If something goes wrong. GOTO 1
>
>
> I'd suggest this approach if possible.

Unfortunately the client is COTS software. I've asked the company for 
such a modification -- i.e. start with a simple GET request so that the 
authorization can finish before sending important POST data -- but they 
have a huge number of customers, and I have little reason to expect this 
to happen in the near future.

>     Just a pragmatic solution i would think. Another crazy idea could
>     be to obtain a Proxy Ticket for your application. It's basically
>     made for working with automated backend work of servers
>     (webservices,imap etc.)
>

Can you give any more details on what this would mean?

Thanks,
Lars


-- 
You are currently subscribed to [email protected] as: 
[email protected]
To unsubscribe, change settings or access archives, see 
http://www.ja-sig.org/wiki/display/JSG/cas-user

Reply via email to