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Date: Fri, 11 Jul 2025 15:16:39 +0200
From: Florian Westphal <fw@strlen.de>
To: Phil Sutter <phil@nwl.cc>, Pablo Neira Ayuso <pablo@netfilter.org>,
	netfilter-devel@vger.kernel.org
Subject: Re: [nf-next RFC] netfilter: nf_tables: Feature ifname-based hook
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Phil Sutter <phil@nwl.cc> wrote:
> On Thu, Jul 10, 2025 at 12:43:03AM +0200, Pablo Neira Ayuso wrote:
> [...]
> > If you accept this suggestion, it is a matter of:
> > 
> > #1 revert the patch in nf.git for the incomplete event notification
> >    (you have three more patches pending for nf-next to complete this
> >     for control plane notifications).
> > #2 add event notifications to net/netfilter/core.c and nfnetlink_hook.
> 
> Since Florian wondered whether I am wasting my time with a quick attempt
> at #2, could you please confirm/deny whether this is a requirement for
> the default to name-based interface hooks or does the 'list hooks'
> extension satisfy the need for user space traceability?

My main point is that rtnetlink has a notifier for new/removed links,
see 'ip monitor.'.

So even if we want a 'nft hooks monitor', I don't see why kernel changes
are needed for it: subscribe to rtnetlink, then for a new link dump
the interfaces hooks *should* work.