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@xxxxxxxxx>: > On 8/12/05, Carlos Zottmann <carlos.zottmann@xxxxxxxxx> 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 >
