From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Hemminger Subject: Re: [PATCH net] net: netlink: filter particular protocols from analyzers Date: Thu, 5 Sep 2013 11:57:55 -0700 Message-ID: <20130905115755.7aec533c@nehalam.linuxnetplumber.net> References: <1378396127-8342-1-git-send-email-dborkman@redhat.com> <20130905.144442.2085221662776542385.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: dborkman@redhat.com, netdev@vger.kernel.org, dborkmann@redhat.com To: David Miller Return-path: Received: from mail-pd0-f169.google.com ([209.85.192.169]:56394 "EHLO mail-pd0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756072Ab3IES57 (ORCPT ); Thu, 5 Sep 2013 14:57:59 -0400 Received: by mail-pd0-f169.google.com with SMTP id r10so2225339pdi.28 for ; Thu, 05 Sep 2013 11:57:58 -0700 (PDT) In-Reply-To: <20130905.144442.2085221662776542385.davem@davemloft.net> Sender: netdev-owner@vger.kernel.org List-ID: On Thu, 05 Sep 2013 14:44:42 -0400 (EDT) David Miller wrote: > From: Daniel Borkmann > Date: Thu, 5 Sep 2013 17:48:47 +0200 > > > From: Daniel Borkmann > > > > Fix finer-grained control and let only a whitelist of allowed netlink > > protocols pass, in our case related to networking. If later on, other > > subsystems decide they want to add their protocol as well to the list > > of allowed protocols they shall simply add it. While at it, we also > > need to tell what protocol is in use otherwise BPF_S_ANC_PROTOCOL can > > not pick it up (as it's not filled out). > > > > Signed-off-by: Daniel Borkmann > > This takes away functionality that I'd be more interesting in using, > namely being able to listen to all netlink protocols using one tap. > > Seriously, when I first saw this feature, that was the first way I'd > imagine myself using it, as a tcpdump for netlink traffic, all of > it. > > If I just want to hear all netlink traffic, don't make me be forced to > know every single NETLINK_* protocol value and have to open that many > sockets just to do so. > > It also makes it so that I can't listen to userlevel custom netlink > protocols, another minus of filtering. > > At the very least, allow an sk_protocol of zero or similar to have this > meaning of "everything". > > I'm not applying this patch, sorry. > -- > To unsubscribe from this list: send the line "unsubscribe netdev" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html If you want filtering, why not add BPF (sk_filter) support to this?