From bae9a78b17b87a7cef56cf492916007a58f65172 Mon Sep 17 00:00:00 2001 From: David Ahern Date: Mon, 15 Oct 2018 18:56:45 -0700 Subject: [PATCH] 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: David Ahern Signed-off-by: David S. Miller --- net/mpls/af_mpls.c | 42 +++++++++++++++++++++++++++++++++++++++++- 1 file changed, 41 insertions(+), 1 deletion(-) diff --git a/net/mpls/af_mpls.c b/net/mpls/af_mpls.c index bfcb4759c9ee..48f4cbd9fb38 100644 --- a/net/mpls/af_mpls.c +++ b/net/mpls/af_mpls.c @@ -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; -- 2.30.2