Commit bae9a78b authored by David Ahern's avatar David Ahern Committed by David S. Miller
Browse files

net/mpls: Plumb support for filtering route dumps 



Implement kernel side filtering of routes by egress device index and
protocol. MPLS uses only a single table and route type.

Signed-off-by: default avatarDavid Ahern <dsahern@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 13e38901

net/mpls/af_mpls.c

+41 −1
Original line number Diff line number Diff line
@@ -2067,12 +2067,35 @@ static int mpls_valid_fib_dump_req(struct net *net, const struct nlmsghdr *nlh, 
}

#endif



static bool mpls_rt_uses_dev(struct mpls_route *rt,

			     const struct net_device *dev)

{

	struct net_device *nh_dev;



	if (rt->rt_nhn == 1) {

		struct mpls_nh *nh = rt->rt_nh;



		nh_dev = rtnl_dereference(nh->nh_dev);

		if (dev == nh_dev)

			return true;

	} else {

		for_nexthops(rt) {

			nh_dev = rtnl_dereference(nh->nh_dev);

			if (nh_dev == dev)

				return true;

		} endfor_nexthops(rt);

	}



	return false;

}



static int mpls_dump_routes(struct sk_buff *skb, struct netlink_callback *cb)

{

	const struct nlmsghdr *nlh = cb->nlh;

	struct net *net = sock_net(skb->sk);

	struct mpls_route __rcu **platform_label;

	struct fib_dump_filter filter = {};

	unsigned int flags = NLM_F_MULTI;

	size_t platform_labels;

	unsigned int index;
@@ -2084,6 +2107,14 @@ static int mpls_dump_routes(struct sk_buff *skb, struct netlink_callback *cb) 
		err = mpls_valid_fib_dump_req(net, nlh, &filter, cb->extack);

		if (err < 0)

			return err;



		/* for MPLS, there is only 1 table with fixed type and flags.

		 * If either are set in the filter then return nothing.

		 */

		if ((filter.table_id && filter.table_id != RT_TABLE_MAIN) ||

		    (filter.rt_type && filter.rt_type != RTN_UNICAST) ||

		     filter.flags)

			return skb->len;

	}



	index = cb->args[0];
@@ -2092,15 +2123,24 @@ static int mpls_dump_routes(struct sk_buff *skb, struct netlink_callback *cb) 


	platform_label = rtnl_dereference(net->mpls.platform_label);

	platform_labels = net->mpls.platform_labels;



	if (filter.filter_set)

		flags |= NLM_F_DUMP_FILTERED;



	for (; index < platform_labels; index++) {

		struct mpls_route *rt;



		rt = rtnl_dereference(platform_label[index]);

		if (!rt)

			continue;



		if ((filter.dev && !mpls_rt_uses_dev(rt, filter.dev)) ||

		    (filter.protocol && rt->rt_protocol != filter.protocol))

			continue;



		if (mpls_dump_route(skb, NETLINK_CB(cb->skb).portid,

				    cb->nlh->nlmsg_seq, RTM_NEWROUTE,

				    index, rt, NLM_F_MULTI) < 0)

				    index, rt, flags) < 0)

			break;

	}

	cb->args[0] = index;