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  
call_fib4_notifier(struct notifier_block * nb,enum fib_event_type event_type,struct fib_notifier_info * info)11  int 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  
call_fib4_notifiers(struct net * net,enum fib_event_type event_type,struct fib_notifier_info * info)19  int 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  	net->ipv4.fib_seq++;
26  	return call_fib_notifiers(net, event_type, info);
27  }
28  
fib4_seq_read(struct net * net)29  static unsigned int fib4_seq_read(struct net *net)
30  {
31  	ASSERT_RTNL();
32  
33  	return net->ipv4.fib_seq + fib4_rules_seq_read(net);
34  }
35  
fib4_dump(struct net * net,struct notifier_block * nb,struct netlink_ext_ack * extack)36  static 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  
48  static 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  
fib4_notifier_init(struct net * net)55  int __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(&fib4_notifier_ops_template, net);
62  	if (IS_ERR(ops))
63  		return PTR_ERR(ops);
64  	net->ipv4.notifier_ops = ops;
65  
66  	return 0;
67  }
68  
fib4_notifier_exit(struct net * net)69  void __net_exit fib4_notifier_exit(struct net *net)
70  {
71  	fib_notifier_ops_unregister(net->ipv4.notifier_ops);
72  }
73