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Date: Mon, 4 Dec 2023 14:01:15 +0100
From: Florian Westphal <fw@strlen.de>
To: Maciej =?utf-8?Q?=C5=BBenczykowski?= <zenczykowski@gmail.com>
Cc: Pablo Neira Ayuso <pablo@netfilter.org>,
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Subject: Re: does nft 'tcp option ... exists' work?
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Maciej Żenczykowski <zenczykowski@gmail.com> wrote:
> wrt. the fix, perhaps this should be fixed both in the kernel and in userspace?
> it seems wrong to have unpredictable endian-ness dependent kernel logic,
> but a userspace fix/workaround would be easier to deploy...

Right.

> Is there some way I could feed raw nf bytecode in via nft syntax (if
> no... should support for this be added?) ?

You could try this:

tcp option @34,8,8 == 34

(where 34 is the kind/option you are looking for).