net: Add support for filtering neigh dump by master device
Add support for filtering neighbor dumps by master device by adding
the NDA_MASTER attribute to the dump request. A new netlink flag,
NLM_F_DUMP_FILTERED, is added to indicate the kernel supports the
request and output is filtered as requested.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Acked-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/neighbour.c b/net/core/neighbour.c
index 2b515ba..8c57fdf 100644
--- a/net/core/neighbour.c
+++ b/net/core/neighbour.c
@@ -2235,14 +2235,42 @@
__neigh_notify(neigh, RTM_NEWNEIGH, 0);
}
+static bool neigh_master_filtered(struct net_device *dev, int master_idx)
+{
+ struct net_device *master;
+
+ if (!master_idx)
+ return false;
+
+ master = netdev_master_upper_dev_get(dev);
+ if (!master || master->ifindex != master_idx)
+ return true;
+
+ return false;
+}
+
static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb,
struct netlink_callback *cb)
{
struct net *net = sock_net(skb->sk);
+ const struct nlmsghdr *nlh = cb->nlh;
+ struct nlattr *tb[NDA_MAX + 1];
struct neighbour *n;
int rc, h, s_h = cb->args[1];
int idx, s_idx = idx = cb->args[2];
struct neigh_hash_table *nht;
+ int filter_master_idx = 0;
+ unsigned int flags = NLM_F_MULTI;
+ int err;
+
+ err = nlmsg_parse(nlh, sizeof(struct ndmsg), tb, NDA_MAX, NULL);
+ if (!err) {
+ if (tb[NDA_MASTER])
+ filter_master_idx = nla_get_u32(tb[NDA_MASTER]);
+
+ if (filter_master_idx)
+ flags |= NLM_F_DUMP_FILTERED;
+ }
rcu_read_lock_bh();
nht = rcu_dereference_bh(tbl->nht);
@@ -2255,12 +2283,14 @@
n = rcu_dereference_bh(n->next)) {
if (!net_eq(dev_net(n->dev), net))
continue;
+ if (neigh_master_filtered(n->dev, filter_master_idx))
+ continue;
if (idx < s_idx)
goto next;
if (neigh_fill_info(skb, n, NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq,
RTM_NEWNEIGH,
- NLM_F_MULTI) < 0) {
+ flags) < 0) {
rc = -1;
goto out;
}