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Date:   Thu, 27 Apr 2023 12:57:30 +0200
From:   Phil Sutter <phil@nwl.cc>
To:     Pablo Neira Ayuso <pablo@netfilter.org>
Cc:     Florian Westphal <fw@strlen.de>, netfilter-devel@vger.kernel.org
Subject: Re: [nf-next PATCH v2] netfilter: nf_tables: Introduce
 NFTA_RULE_ACTUAL_EXPR
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Hi Pablo,

On Wed, Apr 26, 2023 at 09:58:44PM +0200, Pablo Neira Ayuso wrote:
[...]
> My proposal:

Thanks for returning to this. Your approach requires to define a minimum
version from which on forward-compat is guaranteed. I was trying to
avoid this requirement though so things would work for "unknown user
space".

Currently, the only offending extension is ebt_among since it doesn't
exist (and never did) in non-native form. If I implement among extension
parsing (even in non-functional form), my original approach would work.
This also means having a minimum version for full compat, but it affects
ebtables (actually, use of ebt_among) only.

Cheers, Phil