From mboxrd@z Thu Jan 1 00:00:00 1970 From: "John T. Williams" Subject: Re: filtering .mp3 packets Date: Wed, 27 Apr 2005 18:57:03 -0400 Message-ID: <001a01c54b7c$6da1b7f0$660aa8c0@descartes2> References: Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: Sender: linux-newbie-owner@vger.kernel.org List-Id: Content-Type: text/plain; charset="us-ascii" To: linux-newbie@vger.kernel.org I don't know mp3 format, but surely they all have a header that is identifiable? I mean where they store information about the mp3 such as speed and title and such. Surely you could id an mp3 from that information. and terminate the stream. ----- Original Message ----- From: "J." To: Sent: Wednesday, April 27, 2005 3:51 PM Subject: Re: filtering .mp3 packets > On Wed, 27 Apr 2005, simon wrote: > > hello Bill > > > > >>We've been having some difficulty finding the vocabulary to describe > > >>filtering content (for example .mp3 files) over TCP-IP. We would like to > > >>set up our Linux server to do some "trapping" of packets containing .mp3 > > >>files with an eye toward using Linux enabled routing to clean our campus > > >>of an overwhelming dose of music downloads and trading. To do this > > >>exploration, I need to know what I should call the process I'm trying to > > >>perform. Any vocabulary that you can suggest? > > >> > > >>Bill Stanard > > > > may be you can write a kernel module using the netfilter to perform that... > > netfilter is a very powerful way to build every kind of filter. > > you can find some informations here : > > http://www.ouah.org/p61-0x0d_Hacking_the_Linux_Kernel_Network_Stack.txt > > > > regards > > > > simon > Wednesday, April 27 21:36:30 > > Problem is not catching the actual TCP packets, but classifying them like: > This TCP packet is 100% sure, a packet that contains a piece of mp3 data . > > Try to encode a mp3 file, split it into very tiny chunks, remove all but > one, and see if you can guess if it's a mp3 file.. > > There is also encryption to deal with, terrible implemented TCP stacks in > cheap modems and routers when trying to reassemble a whole stream, > disecting, guessing different protocols and levels.. It's definitively > a challenge so to speak.. > > J. > > -- > Don't worry Ma'am. We're university students, - we know what we're doing. > > - > To unsubscribe from this list: send the line "unsubscribe linux-newbie" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.linux-learn.org/faqs - To unsubscribe from this list: send the line "unsubscribe linux-newbie" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.linux-learn.org/faqs