[RFC PATCH bridge 1/5] bridge: Add vlan check to forwarding path
From: Vlad Yasevich <hidden>
Date: 2012-08-23 19:29:58
Subsystem:
ethernet bridge, networking [general], the rest · Maintainers:
Nikolay Aleksandrov, Ido Schimmel, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
When forwarding packets make sure vlan matches any configured vlan for the port. Signed-off-by: Vlad Yasevich <redacted> --- net/bridge/br_forward.c | 17 ++++++++++++++++- net/bridge/br_input.c | 8 ++++++++ net/bridge/br_private.h | 2 ++ 3 files changed, 26 insertions(+), 1 deletions(-)
diff --git a/net/bridge/br_forward.c b/net/bridge/br_forward.c
index e9466d4..ab81954 100644
--- a/net/bridge/br_forward.c
+++ b/net/bridge/br_forward.c@@ -26,11 +26,26 @@ static int deliver_clone(const struct net_bridge_port *prev, void (*__packet_hook)(const struct net_bridge_port *p, struct sk_buff *skb)); -/* Don't forward packets to originating port or forwarding diasabled */ +/* check to see that the vlan is allowed to be forwarded on this interface */ +static inline int vlan_match(const struct net_bridge_port *p, + const struct sk_buff *skb) +{ + unsigned long *vlan_map = rcu_dereference(p->vlan_map); + unsigned short vid = vlan_tx_tag_get(skb) & VLAN_VID_MASK; + + /* The map keeps the vlans off by 1 so adjust for that */ + return (vlan_map && vlan_tx_tag_present(skb) && + test_bit(vid+1, vlan_map)); +} + +/* Don't forward packets to originating port or forwarding diasabled. + */ static inline int should_deliver(const struct net_bridge_port *p, const struct sk_buff *skb) { + return (((p->flags & BR_HAIRPIN_MODE) || skb->dev != p->dev) && + vlan_match(p, skb) && p->state == BR_STATE_FORWARDING); }
diff --git a/net/bridge/br_input.c b/net/bridge/br_input.c
index 76f15fd..b7ca3b3 100644
--- a/net/bridge/br_input.c
+++ b/net/bridge/br_input.c@@ -53,10 +53,18 @@ int br_handle_frame_finish(struct sk_buff *skb) struct net_bridge_fdb_entry *dst; struct net_bridge_mdb_entry *mdst; struct sk_buff *skb2; + unsigned long *vlan_map; if (!p || p->state == BR_STATE_DISABLED) goto drop; + /* If VLAN filter is configured on the port, make sure we accept + * only traffic matching the VLAN filter. + */ + vlan_map = rcu_dereference(p->vlan_map); + if (vlan_map && !test_bit((skb->vlan_tci & VLAN_VID_MASK), vlan_map)) + goto drop; + /* insert into forwarding database after filtering to avoid spoofing */ br = p->br; br_fdb_update(br, p, eth_hdr(skb)->h_source);
diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
index a768b24..8da90e8 100644
--- a/net/bridge/br_private.h
+++ b/net/bridge/br_private.h@@ -152,6 +152,8 @@ struct net_bridge_port #ifdef CONFIG_NET_POLL_CONTROLLER struct netpoll *np; #endif + unsigned long __rcu *vlan_map; + }; #define br_port_exists(dev) (dev->priv_flags & IFF_BRIDGE_PORT)
--
1.7.7.6