Re: [PATCHv3 net-next 06/10] openvswitch: Allow matching on conntrack mark

[Pravin Shelar <pshelar@nicira.com>]

On Tue, Aug 11, 2015 at 3:59 PM, Joe Stringer <joestringer@nicira.com> wrote:
> From: Justin Pettit <jpettit@nicira.com>
>
> Allow matching and setting the conntrack mark field. As with conntrack
> state and zone, these are populated by executing the ct() action. Unlike
> these, the ct_mark is also a writable field. The set_field() action may
> be used to modify the mark, which will take effect on the most recent
> conntrack entry.
>
> E.g.: actions:ct(zone=0),ct(zone=1),set_field(1->ct_mark)
>
> This will perform conntrack lookup in zone 0, then lookup in zone 1,
> then modify the mark for the entry in zone 1. The mark for the entry in
> zone 0 is unchanged. The conntrack entry itself must be committed using
> the "commit" flag in the conntrack action flags for this change to persist.
>
> Signed-off-by: Justin Pettit <jpettit@nicira.com>
> Signed-off-by: Joe Stringer <joestringer@nicira.com>
> ---
...

>
> +int ovs_ct_set_mark(struct sk_buff *skb, struct sw_flow_key *key,
> +                   u32 ct_mark, u32 mask)
> +{
> +#ifdef CONFIG_NF_CONNTRACK_MARK
> +       enum ip_conntrack_info ctinfo;
> +       struct nf_conn *ct;
> +       u32 new_mark;
> +
> +       /* This must happen directly after lookup/commit. */
> +       ct = nf_ct_get(skb, &ctinfo);
> +       if (!ct)
> +               return -EINVAL;
> +
> +       new_mark = ct_mark | (ct->mark & ~(mask));
> +       if (ct->mark != new_mark) {
> +               ct->mark = new_mark;
> +               nf_conntrack_event_cache(IPCT_MARK, ct);
> +               key->ct.mark = ct_mark;
> +       }
> +

Is it fine to set just set mark and not initialize reset of key->ct members?