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 <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David Ahern 2018-10-15 18:56:45 -07:00 committed by David S. Miller
parent 13e38901d4
commit bae9a78b17

View File

@ -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;