Re: [RFC PATCH net-next 5/5] bridge: vlan lwt dst_metadata hooks in ingress and egress paths

[Roopa Prabhu]

On 1/22/17, 4:15 AM, Nikolay Aleksandrov wrote:
> On 21/01/17 06:46, Roopa Prabhu wrote:
>> From: Roopa Prabhu 
>>
>> - ingress hook:
>> - if port is a lwt tunnel port, use tunnel info in
>>   attached dst_metadata to map it to a local vlan
>> - egress hook:
>> - if port is a lwt tunnel port, use tunnel info attached to
>>   vlan to set dst_metadata on the skb
>>
>> CC: Nikolay Aleksandrov 
>> Signed-off-by: Roopa Prabhu 
>> ---
>> CC'ing Nikolay for some more eyes as he has been trying to keep the
>> bridge driver fast path lite.
>>
>>  net/bridge/br_input.c   |4 
>>  net/bridge/br_private.h |4 
>>  net/bridge/br_vlan.c|   55 
>> +++
>>  3 files changed, 63 insertions(+)
>>
>> diff --git a/net/bridge/br_input.c b/net/bridge/br_input.c
>> index 83f356f..96602a1 100644
>> --- a/net/bridge/br_input.c
>> +++ b/net/bridge/br_input.c
>> @@ -262,6 +262,10 @@ rx_handler_result_t br_handle_frame(struct sk_buff 
>> **pskb)
>>  return RX_HANDLER_CONSUMED;
>>  
>>  p = br_port_get_rcu(skb->dev);
>> +if (p->flags & BR_LWT_VLAN) {
>> +if (br_handle_ingress_vlan_tunnel(skb, p, 
>> nbp_vlan_group_rcu(p)))
>> +goto drop;
>> +}
> Is there any reason to do this so early (perhaps netfilter?) ? If not, you 
> can push it to the vlan __allowed_ingress
> (and rename that function to something else, it does a hundred additional 
> things)
> and avoid this check for all packets if vlans are disabled, thus people using 
> non-vlan filtering
> bridge won't have an additional test in their fast path
>
>
yes, forgot to mention it in the commit log. I had it close to 
__allowed_ingress in my first version...had to move it up here
because br_nf_pre_routing/br_nf_pre_routing_finish reset the dst...and hence 
already late..

Re: [RFC PATCH net-next 5/5] bridge: vlan lwt dst_metadata hooks in ingress and egress paths

[Nikolay Aleksandrov]

On 21/01/17 06:46, Roopa Prabhu wrote:
> From: Roopa Prabhu 
> 
> - ingress hook:
> - if port is a lwt tunnel port, use tunnel info in
>   attached dst_metadata to map it to a local vlan
> - egress hook:
> - if port is a lwt tunnel port, use tunnel info attached to
>   vlan to set dst_metadata on the skb
> 
> CC: Nikolay Aleksandrov 
> Signed-off-by: Roopa Prabhu 
> ---
> CC'ing Nikolay for some more eyes as he has been trying to keep the
> bridge driver fast path lite.
> 
>  net/bridge/br_input.c   |4 
>  net/bridge/br_private.h |4 
>  net/bridge/br_vlan.c|   55 
> +++
>  3 files changed, 63 insertions(+)
> 
> diff --git a/net/bridge/br_input.c b/net/bridge/br_input.c
> index 83f356f..96602a1 100644
> --- a/net/bridge/br_input.c
> +++ b/net/bridge/br_input.c
> @@ -262,6 +262,10 @@ rx_handler_result_t br_handle_frame(struct sk_buff 
> **pskb)
>   return RX_HANDLER_CONSUMED;
>  
>   p = br_port_get_rcu(skb->dev);
> + if (p->flags & BR_LWT_VLAN) {
> + if (br_handle_ingress_vlan_tunnel(skb, p, 
> nbp_vlan_group_rcu(p)))
> + goto drop;
> + }

Is there any reason to do this so early (perhaps netfilter?) ? If not, you can 
push it to the vlan __allowed_ingress
(and rename that function to something else, it does a hundred additional 
things)
and avoid this check for all packets if vlans are disabled, thus people using 
non-vlan filtering
bridge won't have an additional test in their fast path

>  
>   if (unlikely(is_link_local_ether_addr(dest))) {
>   u16 fwd_mask = p->br->group_fwd_mask_required;
> diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
> index f68e360..68a23c5 100644
> --- a/net/bridge/br_private.h
> +++ b/net/bridge/br_private.h
> @@ -804,6 +804,10 @@ int __vlan_tunnel_info_del(struct net_bridge_vlan_group 
> *vg,
>  int nbp_vlan_tunnel_info_add(struct net_bridge_port *port, u16 vid, u32 
> tun_id);
>  bool vlan_tunnel_id_isrange(struct net_bridge_vlan *v_end,
>   struct net_bridge_vlan *v);
> +int br_handle_ingress_vlan_tunnel(struct sk_buff *skb, struct 
> net_bridge_port *p,
> +   struct net_bridge_vlan_group *vg);
> +int br_handle_egress_vlan_tunnel(struct sk_buff *skb,
> +  struct net_bridge_vlan *vlan);
>  
>  static inline struct net_bridge_vlan_group *br_vlan_group(
>   const struct net_bridge *br)
> diff --git a/net/bridge/br_vlan.c b/net/bridge/br_vlan.c
> index 2040f08..6cf2344 100644
> --- a/net/bridge/br_vlan.c
> +++ b/net/bridge/br_vlan.c
> @@ -405,6 +405,11 @@ struct sk_buff *br_handle_vlan(struct net_bridge *br,
>  
>   if (v->flags & BRIDGE_VLAN_INFO_UNTAGGED)
>   skb->vlan_tci = 0;
> +
> + if (br_handle_egress_vlan_tunnel(skb, v)) {
> + kfree_skb(skb);
> + return NULL;
> + }
>  out:
>   return skb;
>  }
> @@ -1213,3 +1218,53 @@ int nbp_vlan_tunnel_info_delete(struct net_bridge_port 
> *port, u16 vid)
>  
>   return 0;
>  }
> +
> +int br_handle_ingress_vlan_tunnel(struct sk_buff *skb,
> +   struct net_bridge_port *p,
> +   struct net_bridge_vlan_group *vg)
> +{
> + struct ip_tunnel_info *tinfo = skb_tunnel_info(skb);
> + struct net_bridge_vlan *vlan;
> +
> + if (!vg || !tinfo)
> + return 0;
> +
> + /* if already tagged, ignore */
> + if (skb_vlan_tagged(skb))
> + return 0;
> +
> + /* lookup vid, given tunnel id */
> + vlan = br_vlan_tunnel_lookup(>tunnel_hash, tinfo->key.tun_id);
> + if (!vlan)
> + return 0;
> +
> + skb_dst_drop(skb);
> +
> + __vlan_hwaccel_put_tag(skb, p->br->vlan_proto, vlan->vid);
> +
> + return 0;
> +}
> +
> +int br_handle_egress_vlan_tunnel(struct sk_buff *skb,
> +  struct net_bridge_vlan *vlan)
> +{
> + __be32 tun_id;
> + int err;
> +
> + if (!vlan || !vlan->tinfo.tunnel_id)
> + return 0;
> +
> + if (unlikely(!skb_vlan_tag_present(skb)))
> + return 0;
> +
> + skb_dst_drop(skb);
> + tun_id = tunnel_id_to_key32(vlan->tinfo.tunnel_id);
> +
> + err = skb_vlan_pop(skb);
> + if (err)
> + return err;
> +
> + skb_dst_set(skb, dst_clone(>tinfo.tunnel_dst->dst));
> +
> + return 0;
> +}
>