net/ipv4/tcp_diag.c

   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
  13 #include <linux/module.h>
  14 #include <linux/inet_diag.h>
  15
  16 #include <linux/tcp.h>
  17
  18 #include <net/tcp.h>
  19
  20 static void tcp_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
  21                               void *_info)
  22 {
  23         const struct tcp_sock *tp = tcp_sk(sk);
  24         struct tcp_info *info = _info;
  25
  26         if (sk->sk_state == TCP_LISTEN) {
  27                 r->idiag_rqueue = sk->sk_ack_backlog;
  28                 r->idiag_wqueue = sk->sk_max_ack_backlog;
  29         } else {
  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 != NULL)
  34                 tcp_get_info(sk, info);
  35 }
  36
  37 static const struct inet_diag_handler tcp_diag_handler = {
  38         .idiag_hashinfo  = &tcp_hashinfo,
  39         .idiag_get_info  = tcp_diag_get_info,
  40         .idiag_type      = TCPDIAG_GETSOCK,
  41         .idiag_info_size = sizeof(struct tcp_info),
  42 };
  43
  44 static int __init tcp_diag_init(void)
  45 {
  46         return inet_diag_register(&tcp_diag_handler);
  47 }
  48
  49 static void __exit tcp_diag_exit(void)
  50 {
  51         inet_diag_unregister(&tcp_diag_handler);
  52 }
  53
  54 module_init(tcp_diag_init);
  55 module_exit(tcp_diag_exit);
  56 MODULE_LICENSE("GPL");
  57 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_INET_DIAG, TCPDIAG_GETSOCK);