xref: /openbmc/linux/net/ipv4/tcp_diag.c (revision 2572f00d)
1 /*
2  * tcp_diag.c	Module for monitoring TCP transport protocols sockets.
3  *
4  * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
5  *
6  *	This program is free software; you can redistribute it and/or
7  *      modify it under the terms of the GNU General Public License
8  *      as published by the Free Software Foundation; either version
9  *      2 of the License, or (at your option) any later version.
10  */
11 
12 #include <linux/module.h>
13 #include <linux/inet_diag.h>
14 
15 #include <linux/tcp.h>
16 
17 #include <net/tcp.h>
18 
19 static void tcp_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
20 			      void *_info)
21 {
22 	struct tcp_info *info = _info;
23 
24 	if (sk_state_load(sk) == TCP_LISTEN) {
25 		r->idiag_rqueue = sk->sk_ack_backlog;
26 		r->idiag_wqueue = sk->sk_max_ack_backlog;
27 	} else if (sk->sk_type == SOCK_STREAM) {
28 		const struct tcp_sock *tp = tcp_sk(sk);
29 
30 		r->idiag_rqueue = max_t(int, tp->rcv_nxt - tp->copied_seq, 0);
31 		r->idiag_wqueue = tp->write_seq - tp->snd_una;
32 	}
33 	if (info)
34 		tcp_get_info(sk, info);
35 }
36 
37 static void tcp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
38 			  const struct inet_diag_req_v2 *r, struct nlattr *bc)
39 {
40 	inet_diag_dump_icsk(&tcp_hashinfo, skb, cb, r, bc);
41 }
42 
43 static int tcp_diag_dump_one(struct sk_buff *in_skb, const struct nlmsghdr *nlh,
44 			     const struct inet_diag_req_v2 *req)
45 {
46 	return inet_diag_dump_one_icsk(&tcp_hashinfo, in_skb, nlh, req);
47 }
48 
49 static const struct inet_diag_handler tcp_diag_handler = {
50 	.dump		 = tcp_diag_dump,
51 	.dump_one	 = tcp_diag_dump_one,
52 	.idiag_get_info	 = tcp_diag_get_info,
53 	.idiag_type	 = IPPROTO_TCP,
54 	.idiag_info_size = sizeof(struct tcp_info),
55 };
56 
57 static int __init tcp_diag_init(void)
58 {
59 	return inet_diag_register(&tcp_diag_handler);
60 }
61 
62 static void __exit tcp_diag_exit(void)
63 {
64 	inet_diag_unregister(&tcp_diag_handler);
65 }
66 
67 module_init(tcp_diag_init);
68 module_exit(tcp_diag_exit);
69 MODULE_LICENSE("GPL");
70 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-6 /* AF_INET - IPPROTO_TCP */);
71