Re: [squid-users] Blocking Web bugs?

Hi Kevin !!

Thanks for the answer .... I was afraid of something like that, but it
is good to know it anyway ...

Regards,
Carlos.

2005/8/13, Kevin <kkadow@gmail.com>:
> On 8/12/05, Carlos Zottmann <carlos.zottmann@gmail.com> wrote:
> > Does anyone know a way to block web bugs (0x0 gifs) with squid?
>
> Interesting question.
>
> Since the function of a web bug is fulfilled when the URL is retrieved
> from the remote server, and since Squid can't see the GIF's dimensions
> until after the object is received, I'd say it's technically impossible
> to effectively block web bugs using Squid, short of composing a regular
> expression to match all likely tracking bug URLs (watch out for false
> positives).
>
> You could certainly modify Squid (or any caching proxy) to detect when
> a received image has dimensions below a certain minimum, and react by
> forcing any _future_ requests for that object to be served from cache
> regardless of the headers supplied by the server or a cookie or other
> header requested by the client. This wouldn't help the first time any
> user triggers a web bug, but would effectively keep private any future
> requests for that same exact URL.
>
> Kevin Kadow
>
Received on Mon Aug 15 2005 - 05:49:31 MDT