1// SPDX-License-Identifier: GPL-2.0
2#include <linux/rtnetlink.h>
3#include <linux/notifier.h>
4#include <linux/socket.h>
5#include <linux/kernel.h>
6#include <linux/export.h>
7#include <net/net_namespace.h>
8#include <net/fib_notifier.h>
9#include <net/ip_fib.h>
10
11int call_fib4_notifier(struct notifier_block *nb,
12 enum fib_event_type event_type,
13 struct fib_notifier_info *info)
14{
15 info->family = AF_INET;
16 return call_fib_notifier(nb, event_type, info);
17}
18
19int call_fib4_notifiers(struct net *net, enum fib_event_type event_type,
20 struct fib_notifier_info *info)
21{
22 ASSERT_RTNL();
23
24 info->family = AF_INET;
25 /* Paired with READ_ONCE() in fib4_seq_read() */
26 WRITE_ONCE(net->ipv4.fib_seq, net->ipv4.fib_seq + 1);
27 return call_fib_notifiers(net, event_type, info);
28}
29
30static unsigned int fib4_seq_read(const struct net *net)
31{
32 /* Paired with WRITE_ONCE() in call_fib4_notifiers() */
33 return READ_ONCE(net->ipv4.fib_seq) + fib4_rules_seq_read(net);
34}
35
36static int fib4_dump(struct net *net, struct notifier_block *nb,
37 struct netlink_ext_ack *extack)
38{
39 int err;
40
41 err = fib4_rules_dump(net, nb, extack);
42 if (err)
43 return err;
44
45 return fib_notify(net, nb, extack);
46}
47
48static const struct fib_notifier_ops fib4_notifier_ops_template = {
49 .family = AF_INET,
50 .fib_seq_read = fib4_seq_read,
51 .fib_dump = fib4_dump,
52 .owner = THIS_MODULE,
53};
54
55int __net_init fib4_notifier_init(struct net *net)
56{
57 struct fib_notifier_ops *ops;
58
59 net->ipv4.fib_seq = 0;
60
61 ops = fib_notifier_ops_register(tmpl: &fib4_notifier_ops_template, net);
62 if (IS_ERR(ptr: ops))
63 return PTR_ERR(ptr: ops);
64 net->ipv4.notifier_ops = ops;
65
66 return 0;
67}
68
69void __net_exit fib4_notifier_exit(struct net *net)
70{
71 fib_notifier_ops_unregister(ops: net->ipv4.notifier_ops);
72}
73