On Mon, 2014-06-09 at 08:52 -0700, Stephen Hemminger wrote:
> On Mon, 9 Jun 2014 20:34:46 +0900
> Toshiaki Makita <makita.toshiaki@xxxxxxxxxxxxx> wrote:
>
> > An 802.1ad bridge must forward the Nearest Customer Bridge group addresses.
> > 01-80-C2-00-00-00
> > 01-80-C2-00-00-0B
> > 01-80-C2-00-00-0C
> > 01-80-C2-00-00-0D
> > 01-80-C2-00-00-0F
> > (For details, see IEEE 802.1Q-2011 8.6.3.)
> >
> > An exception is the br->group_addr, which needs to be passed to the higher
> > layer entity so that STP works.
> >
> > Signed-off-by: Toshiaki Makita <makita.toshiaki@xxxxxxxxxxxxx>
> > ---
> > net/bridge/br_input.c | 15 ++++++++++++++-
> > net/bridge/br_private.h | 10 ++++++++++
> > 2 files changed, 24 insertions(+), 1 deletion(-)
> >
> > diff --git a/net/bridge/br_input.c b/net/bridge/br_input.c
> > index 04d6348..b05d419 100644
> > --- a/net/bridge/br_input.c
> > +++ b/net/bridge/br_input.c
> > @@ -194,13 +194,26 @@ rx_handler_result_t br_handle_frame(struct sk_buff **pskb)
> > case 0x00: /* Bridge Group Address */
> > /* If STP is turned off,
> > then must forward to keep loop detection */
> > - if (p->br->stp_enabled == BR_NO_STP)
> > + if (p->br->stp_enabled == BR_NO_STP ||
> > + (br_vlan_enabled(p->br) &&
> > + br_vlan_get_proto(p->br) == htons(ETH_P_8021AD) &&
> > + p->br->group_addr[5] != dest[5]))
> > goto forward;
> > break;
> >
> > case 0x01: /* IEEE MAC (Pause) */
> > goto drop;
> >
> > + case 0x0B:
> > + case 0x0C:
> > + case 0x0D:
> > + case 0x0F:
> > + /* The Nearest Customer Bridge group address */
> > + if (br_vlan_enabled(p->br) &&
> > + br_vlan_get_proto(p->br) == htons(ETH_P_8021AD) &&
> > + p->br->group_addr[5] != dest[5])
> > + goto forward;
> > + /* fall through */
> > default:
> > /* Allow selective forwarding for most other protocols */
> > if (p->br->group_fwd_mask & (1u << dest[5]))
> > diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
> > index b65fee9..65204c2 100644
> > --- a/net/bridge/br_private.h
> > +++ b/net/bridge/br_private.h
> > @@ -647,6 +647,11 @@ static inline int br_vlan_enabled(struct net_bridge *br)
> > {
> > return br->vlan_enabled;
> > }
> > +
> > +static inline __be16 br_vlan_get_proto(struct net_bridge *br)
> > +{
> > + return br->vlan_proto;
> > +}
> > #else
> > static inline bool br_allowed_ingress(struct net_bridge *br,
> > struct net_port_vlans *v,
> > @@ -742,6 +747,11 @@ static inline int br_vlan_enabled(struct net_bridge *br)
> > {
> > return 0;
> > }
> > +
> > +static inline __be16 br_vlan_get_proto(struct net_bridge *br)
> > +{
> > + return 0;
> > +}
> > #endif
> >
> > /* br_netfilter.c */
>
> Rather than special casing this around vlan filtering, I would prefer
> the code always forward these packets, or manipulate group_fwd_mask
> to allow it that way.
These addresses must be forwarded only if the bridge is an S-VLAN
bridge. When it is a C-VLAN bridge or a .1D bridge, they may not be
forwarded. So, I don't think we can forward them always.
Using group_fwd_mask is a bit complicated. If we use it to forward them,
user can optionally turn off forwarding ability of those addresses...
but we maybe need another information (named like group_fwd_mask_set)
that indicates which bit is set by user. (We have to set group_fwd_mask
automatically when we set vlan_proto to 88a8.)
Is this way acceptable?
Thanks,
Toshiaki Makita
