netdev - Re: [PATCH net-next RFC v5 4/4] net/sched: act_blockcast: Introduce blockcast tc action

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date: Thu, 23 Nov 2023 06:29:00 -0800
From: Marcelo Ricardo Leitner <mleitner@...hat.com>
To: Jamal Hadi Salim <jhs@...atatu.com>
Cc: Jiri Pirko <jiri@...nulli.us>, Victor Nogueira <victor@...atatu.com>, davem@...emloft.net, 
	edumazet@...gle.com, kuba@...nel.org, pabeni@...hat.com, 
	xiyou.wangcong@...il.com, vladbu@...dia.com, paulb@...dia.com, 
	pctammela@...atatu.com, netdev@...r.kernel.org, kernel@...atatu.com
Subject: Re: [PATCH net-next RFC v5 4/4] net/sched: act_blockcast: Introduce
 blockcast tc action

On Thu, Nov 23, 2023 at 08:37:13AM -0500, Jamal Hadi Salim wrote:
> On Thu, Nov 23, 2023 at 3:51 AM Jiri Pirko <jiri@...nulli.us> wrote:
> >
> > Fri, Nov 10, 2023 at 10:46:18PM CET, victor@...atatu.com wrote:
> > >This action takes advantage of the presence of tc block ports set in the
> > >datapath and multicasts a packet to ports on a block. By default, it will
> > >broadcast the packet to a block, that is send to all members of the block except
> > >the port in which the packet arrived on. However, the user may specify
> > >the option "tx_type all", which will send the packet to all members of the
> > >block indiscriminately.
> > >
> > >Example usage:
> > >    $ tc qdisc add dev ens7 ingress_block 22
> > >    $ tc qdisc add dev ens8 ingress_block 22
> > >
> > >Now we can add a filter to broadcast packets to ports on ingress block id 22:
> > >$ tc filter add block 22 protocol ip pref 25 \
> > >  flower dst_ip 192.168.0.0/16 action blockcast blockid 22
> >
> > Name the arg "block" so it is consistent with "filter add block". Make
> > sure this is aligned netlink-wise as well.
> >
> >
> > >
> > >Or if we wish to send to all ports in the block:
> > >$ tc filter add block 22 protocol ip pref 25 \
> > >  flower dst_ip 192.168.0.0/16 action blockcast blockid 22 tx_type all
> >
> > I read the discussion the the previous version again. I suggested this
> > to be part of mirred. Why exactly that was not addressed?
> >
>
> I am the one who pushed back (in that discussion). Actions should be

Me too, and actually I thought Jiri had agreed to it with some
remarks to be addressed (which I don't know if there were, I didn't
read this version yet).

> small and specific. Like i had said in that earlier discussion it was
> a mistake to make mirred do both mirror and redirect - they should
> have been two actions. So i feel like adding a block to mirred is
> adding more knobs. We are also going to add dev->group as a way to
> select what devices to mirror to. Should that be in mirred as well?
>
> cheers,
> jamal
>
> > Instead of:
> > $ tc filter add block 22 protocol ip pref 25 \
> >   flower dst_ip 192.168.0.0/16 action blockcast blockid 22
> > You'd have:
> > $ tc filter add block 22 protocol ip pref 25 \
> >   flower dst_ip 192.168.0.0/16 action mirred egress redirect block 22
> >
> > I don't see why we need special action for this.
> >
> > Regarding "tx_type all":
> > Do you expect to have another "tx_type"? Seems to me a bit odd. Why not
> > to have this as "no_src_skip" or some other similar arg, without value
> > acting as a bool (flag) on netlink level.
> >
> >
>