bridge: mcast: add support for more router port information dumping

Allow for more multicast router port information to be dumped such as
timer and type attributes. For that that purpose we need to extend the
MDBA_ROUTER_PORT attribute similar to how it was done for the mdb entries
recently. The new format is thus:
[MDBA_ROUTER_PORT] = { <- nested attribute
    u32 ifindex <- router port ifindex for user-space compatibility
    [MDBA_ROUTER_PATTR attributes]
}
This way it remains compatible with older users (they'll simply retrieve
the u32 in the beginning) and new users can parse the remaining
attributes. It would also allow to add future extensions to the router
port without breaking compatibility.

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/uapi/linux/if_bridge.h b/include/uapi/linux/if_bridge.h
index 74ee03a47e79ea4818ae52c5ac2037eade35845e..0536eefff9bfee41c0de6088f38cf84b1d29a12f 100644 (file)
--- a/include/uapi/linux/if_bridge.h
+++ b/include/uapi/linux/if_bridge.h
@@ -144,7 +144,10 @@ struct bridge_vlan_info {
  *     }
  * }
  * [MDBA_ROUTER] = {
- *    [MDBA_ROUTER_PORT]
+ *    [MDBA_ROUTER_PORT] = {
+ *        u32 ifindex
+ *        [MDBA_ROUTER_PATTR attributes]
+ *    }
  * }
  */
 enum {
@@ -192,6 +195,15 @@ enum {
 };
 #define MDBA_ROUTER_MAX (__MDBA_ROUTER_MAX - 1)
 
+/* router port attributes */
+enum {
+       MDBA_ROUTER_PATTR_UNSPEC,
+       MDBA_ROUTER_PATTR_TIMER,
+       MDBA_ROUTER_PATTR_TYPE,
+       __MDBA_ROUTER_PATTR_MAX
+};
+#define MDBA_ROUTER_PATTR_MAX (__MDBA_ROUTER_PATTR_MAX - 1)
+
 struct br_port_msg {
        __u8  family;
        __u32 ifindex;

diff --git a/net/bridge/br_mdb.c b/net/bridge/br_mdb.c
index 73786e2fe0653e9e560aa40b755ee9fc4ef349d7..253bc77eda3bd1106021a7d93ba6854964f0a935 100644 (file)
--- a/net/bridge/br_mdb.c
+++ b/net/bridge/br_mdb.c
@@ -20,7 +20,7 @@ static int br_rports_fill_info(struct sk_buff *skb, struct netlink_callback *cb,
 {
        struct net_bridge *br = netdev_priv(dev);
        struct net_bridge_port *p;
-       struct nlattr *nest;
+       struct nlattr *nest, *port_nest;
 
        if (!br->multicast_router || hlist_empty(&br->router_list))
                return 0;
@@ -30,8 +30,20 @@ static int br_rports_fill_info(struct sk_buff *skb, struct netlink_callback *cb,
                return -EMSGSIZE;
 
        hlist_for_each_entry_rcu(p, &br->router_list, rlist) {
-               if (p && nla_put_u32(skb, MDBA_ROUTER_PORT, p->dev->ifindex))
+               if (!p)
+                       continue;
+               port_nest = nla_nest_start(skb, MDBA_ROUTER_PORT);
+               if (!port_nest)
                        goto fail;
+               if (nla_put_nohdr(skb, sizeof(u32), &p->dev->ifindex) ||
+                   nla_put_u32(skb, MDBA_ROUTER_PATTR_TIMER,
+                               br_timer_value(&p->multicast_router_timer)) ||
+                   nla_put_u8(skb, MDBA_ROUTER_PATTR_TYPE,
+                              p->multicast_router)) {
+                       nla_nest_cancel(skb, port_nest);
+                       goto fail;
+               }
+               nla_nest_end(skb, port_nest);
        }
 
        nla_nest_end(skb, nest);