From mboxrd@z Thu Jan 1 00:00:00 1970 From: Patrick McHardy Subject: Re: [PATCH] entry_data Date: Mon, 19 Jun 2006 19:34:47 +0200 Message-ID: <4496E037.2000706@trash.net> References: <200606050029.08602.max@nucleus.it> <448FD0F6.3010506@anduras.de> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Cc: Massimiliano Hofer , netfilter-devel@lists.netfilter.org Return-path: To: Sven Anders In-Reply-To: <448FD0F6.3010506@anduras.de> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: netfilter-devel-bounces@lists.netfilter.org Errors-To: netfilter-devel-bounces@lists.netfilter.org List-Id: netfilter-devel.vger.kernel.org Sven Anders wrote: > Massimiliano Hofer schrieb: > >>Hi, >>here is my proposed patch for an API change that supports entry specific data. >> >>As explained in my previous posts the purpose of this patch is to give matches >>the opportunity to store entry specific data. Several matches already achieve >>this reserving some space in the data fields, but these come from userspace >>and I don't think it is the Right Way(TM) to do it. > > > Does this mean we can reuse these fields for other puroposes without breaking > compatibility with iptables? Yes, userspace ignores these fields. I still haven't really made up my mind about this patch yet. I don't like the void ** approach very much, but I didn't got around to thinking about something better yet. Please stay patient with me :) > I'm particularly interested in adding a negation to the "limit" match and I > think the match is using one of these special data fields... > > > /* Ugly, ugly fucker. */ > > struct xt_rateinfo *master; > > If this gives us the possibility to add the negation, who do we distinguish > between the old and new limit version. In other words: Who do we reach a maximum > compatibility? IIRC userspace zeroes this field, so you could just do the usual "0 -> no inversion, 1 -> inversion" thing and it would behave correctly for both old and new userspace. But you need check yourself if this is indeed true, I'm not really sure.