net: Enable kernel side filtering of route dumps
Update parsing of route dump request to enable kernel side filtering.
Allow filtering results by protocol (e.g., which routing daemon installed
the route), route type (e.g., unicast), table id and nexthop device. These
amount to the low hanging fruit, yet a huge improvement, for dumping
routes.
ip_valid_fib_dump_req is called with RTNL held, so __dev_get_by_index can
be used to look up the device index without taking a reference. From
there filter->dev is only used during dump loops with the lock still held.
Set NLM_F_DUMP_FILTERED in the answer_flags so the user knows the results
have been filtered should no entries be returned.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c
index a51fc35..5562c77 100644
--- a/net/ipv6/ip6_fib.c
+++ b/net/ipv6/ip6_fib.c
@@ -580,7 +580,7 @@ static int inet6_dump_fib(struct sk_buff *skb, struct netlink_callback *cb)
if (cb->strict_check) {
int err;
- err = ip_valid_fib_dump_req(net, nlh, &arg.filter, cb->extack);
+ err = ip_valid_fib_dump_req(net, nlh, &arg.filter, cb);
if (err < 0)
return err;
} else if (nlmsg_len(nlh) >= sizeof(struct rtmsg)) {