From: Ian Pilcher <arequipeno@gmail.com>
To: "netfilter@vger.kernel.org" <netfilter@vger.kernel.org>
Subject: How to determine type of nftables set
Date: Mon, 8 Dec 2025 17:32:27 -0600 [thread overview]
Message-ID: <067a7b31-699f-4642-af16-9062c69e9fe2@gmail.com> (raw)
I am working on an application that will be working with pre-existing
(created by the system administrator) netfilter sets. These sets should
contain either IPv4 of IPv6 addresses.
How can my application determine what type of address a particular set
holds? I can query the set and get a NFT_MSG_GETSET message back, but
it's murky after that.
The message contains a NFTA_SET_KEY_TYPE attribute, which looks
promising, but I can't find anything telling me how to interpret it.
ChatGPT says that I should just look at the NFTA_SET_KEY_LEN attribute,
but that doesn't seem reliable; how would I distinguish a 32-bit IPv4
address from 2 16-bit ports?
Short of digging through the source code of nft, how am I supposed to do
this?
TIA!
--
========================================================================
If your user interface is intuitive in retrospect ... it isn't intuitive
========================================================================
next reply other threads:[~2025-12-08 23:32 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-12-08 23:32 Ian Pilcher [this message]
2025-12-11 12:55 ` How to determine type of nftables set Florian Westphal
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