Date: Mon, 21 Jun 1999 11:05:16 +0200 (MET DST) From: Luigi Rizzo <luigi@labinfo.iet.unipi.it> To: stan@osgroup.com Cc: hackers@FreeBSD.ORG Subject: Re: ipfilter (was: RE: Introduction) Message-ID: <199906210905.LAA21570@labinfo.iet.unipi.it> In-Reply-To: <01BEBB25.A7F332F0.stan@osgroup.com> from "Constantine Shkolny" at Jun 20, 99 02:03:01 pm
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> > this might ease life to those who want to replace ipfw with ipfilter > > for dummynet or similar things, if nothing else. > > Thank you, Luigi. Could you please help me with some basics? ... what i do in dummynet is to queue the packet (wheter it comes from ip_input() or ip_output() makes no difference) in the appropriate data structure for further processing, and return as if the firewall deleted the packet. Subsequently, when processing is done (in dummynet this means some time has passed and we get a timer interrupt, in your case i suppose your interrupt service routine would get called in this case), reinvoke the appropriate routine (p_input() or ip_output()) with the packet prepended with a header so that it can distinguish the processed packet from a new one and act differently. > If would be nice to have another hook point in a proper place _after_ > the re-assembly stage of ip_input(). It would not cause much overhead > if nobody has a hook installed. i did not have this problem with dummynet -- if you need the reassembly first, then probably you have to hook in ip_input() after the reassembly is done, ie between IP and the upper layer i guess. cheers luigi -----------------------------------+------------------------------------- Luigi RIZZO, luigi@iet.unipi.it . Dip. di Ing. dell'Informazione http://www.iet.unipi.it/~luigi/ . Universita` di Pisa TEL/FAX: +39-050-568.533/522 . via Diotisalvi 2, 56126 PISA (Italy) http://www.iet.unipi.it/~luigi/ngc99/ ==== First International Workshop on Networked Group Communication ==== -----------------------------------+------------------------------------- To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message
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