Sriram Yagnaraman <sriram.yagnaraman@xxxxxxxx> wrote:
> > -----Original Message-----
> > From: Florian Westphal <fw@xxxxxxxxx>
> > Sent: Friday, 24 February 2023 00:02
> > To: Sriram Yagnaraman <sriram.yagnaraman@xxxxxxxx>
> > Cc: netfilter-devel@xxxxxxxxxxxxxxx; Florian Westphal <fw@xxxxxxxxx>; Pablo
> > Neira Ayuso <pablo@xxxxxxxxxxxxx>
> > Subject: Re: [PATCH nf-next] netfilter: bridge: introduce broute meta
> > statement
> >
> > Sriram Yagnaraman <sriram.yagnaraman@xxxxxxxx> wrote:
> > > +void nft_meta_bridge_set_eval(const struct nft_expr *expr,
> > > + struct nft_regs *regs,
> > > + const struct nft_pktinfo *pkt)
> >
> > static?
> >
> > > +{
> > > + dest = eth_hdr(skb)->h_dest;
> > > + if (skb->pkt_type == PACKET_HOST &&
> > > + !ether_addr_equal(skb->dev->dev_addr, dest) &&
> > > + ether_addr_equal(p->br->dev->dev_addr, dest))
> > > + skb->pkt_type = PACKET_OTHERHOST;
> >
> > We already support override of skb->pkt_type, I would prefer if users to this
> > explicitly from their ruleset if they need it.
>
> Ok, that is better, I will remove this chunk.
>
> >
> > > + priv->key = ntohl(nla_get_be32(tb[NFTA_META_KEY]));
> >
> > I think you need to check for !tb[NFTA_META_KEY] and bail out before this
> > line.
>
> We already validate this in nft_meta_bridge_select_ops(), isn’t that enough?
Right, thats enough.
> > > + switch (priv->key) {
> > > + case NFT_META_BRI_BROUTE:
> > > + len = sizeof(u8);
> > > + break;
> >
> > Can you bail out if this is called from something else than PREROUTING hook?
> >
> > You can look at nft_tproxy.c or similar on how to do this.
>
> nft_meta_set_validate() already checks meta statements can only be used in the PREROUTING hook. Isn't that enough?
It only restricts NFT_META_PKTTYPE.
