Re: [nf-next RFC] netfilter: nf_tables: Feature ifname-based hook registration

[Phil Sutter <phil@nwl.cc>]

Florian!

On Fri, Jul 04, 2025 at 04:04:39PM +0200, Florian Westphal wrote:
> Phil Sutter <phil@nwl.cc> wrote:
> > Please keep in mind we already have 'nft list hooks' which provides
> > hints in that direction. It does not show which flowtable/chain actually
> > binds to a given device, though.
> 
> Its possible to extend it:
> - add NF_HOOK_OP_NFT_FT to enum nf_hook_ops_type
> - add
> 
> static int nfnl_hook_put_nft_ft_info(struct sk_buff *nlskb,
>                                    const struct nfnl_dump_hook_data *ctx,
>                                    unsigned int seq,
>                                    struct nf_flowtable *ft)
> 
> to nfnetlink_hook.c
> 
> it can use container_of to get to the nft_flowtable struct.
> It might be possibe to share some code with nfnl_hook_put_nft_chain_info
> and reuse some of the same netlink attributes.
> 
> - call it from nfnl_hook_dump_one.
> 
> I think it would use useful to have, independent of "eth*" support.

I entirely missed the fact that 'list hooks' output sucks with
flowtables only and is fine with chains! Thanks for the quick howto,
I'll implement this next week.

Thanks, Phil