On Fri, Sep 13, 2024 at 12:41:01PM +0200, Florian Westphal wrote: > Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> wrote: > > On Fri, Sep 13, 2024 at 12:23:47PM +0200, Florian Westphal wrote: > > > Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> wrote: > > > > tproxy action must be terminal since the intent of the user to steal the > > > > traffic and redirect to the port. > > > > Align this behaviour to iptables to make it easier to migrate by issuing > > > > NF_ACCEPT for packets that are redirect to userspace process socket. > > > > Otherwise, NF_DROP packet if socket transparent flag is not set on. > > > > > > The nonterminal behaviour is intentional. This change will likely > > > break existing setups. > > > > > > nft add rule filter divert tcp dport 80 tproxy to :50080 meta mark set 1 accept > > > > > > This is a documented example. > > > > Ouch. Example could have been: > > > > nft add rule filter divert tcp dport 80 socket transparent meta set 1 tproxy to :50080 > > Yes, but its not the same. > > With the statements switched, all tcp dport 80 have the mark set. > With original example, the mark is set only if tproxy found a > transparent sk. Indeed, thanks for correcting me. I'm remembering now why this was done to provide to address the ugly mark hack that xt_TPROXY provides. While this is making harder to migrate, making it non-terminal is allowing to make more handling such as ct/meta marking after it. I think we just have to document this in man nft(8).
