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Date:   Wed, 15 Nov 2023 10:27:34 +0100
From:   Pablo Neira Ayuso <pablo@netfilter.org>
To:     Netfilter Development <netfilter-devel@vger.kernel.org>
Subject: Re: libnfnetlink dependency elimination (doc)
Message-ID: <ZVSPBsJOILgw3c0m@calendula>
References: <20231112065922.3414-1-duncan_roe@optusnet.com.au>
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On Wed, Nov 15, 2023 at 10:04:47AM +1100, Duncan Roe wrote:
> Hi Pablo,
> 
> On Tue, Nov 14, 2023 at 04:24:11PM +0100, Pablo Neira Ayuso wrote:
> > On Sun, Nov 12, 2023 at 05:59:21PM +1100, Duncan Roe wrote:
> > > Some of these documented changes haven't happened yet.
> >
> > Then we have to start by changes first, not the other way around.
> 
> Yes I know that, obviously:)
> 
> The point here is that nfnl_rcvbufsiz() has been advertised in the main page of
> libnetfilter_queue HTML for a long time and there are likely a number of systems
> out there that use it. When libnfnetlink is removed, libnetfilter_queue will
> have to provide nfnl_rcvbufsiz() or those systems will start failing.

There is nfq_fd() and setsockopt() that you can use:

        setsockopt(fd, SOL_SOCKET, SO_RCVBUFFORCE, &size, socklen);
        setsockopt(fd, SOL_SOCKET, SO_RCVBUF, &size, socklen);

libnfnetlink is **deprecated** and it will be removed at some point,
the git log shows that it has less and less users.

main libnfnetlink users are the libnetfilter_* libraries.

No new application should be using libnfnetlink in 2023.