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 #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         const struct tcp_sock *tp = tcp_sk(sk);
  23         struct tcp_info *info = _info;
  24
  25         if (sk->sk_state == TCP_LISTEN) {
  26                 r->idiag_rqueue = sk->sk_ack_backlog;
  27                 r->idiag_wqueue = sk->sk_max_ack_backlog;
  28         } else {
  29                 r->idiag_rqueue = max_t(int, tp->rcv_nxt - tp->copied_seq, 0);
  30                 r->idiag_wqueue = tp->write_seq - tp->snd_una;
  31         }
  32         if (info != NULL)
  33                 tcp_get_info(sk, info);
  34 }
  35
  36 static void tcp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
  37                           struct inet_diag_req_v2 *r, struct nlattr *bc)
  38 {
  39         inet_diag_dump_icsk(&tcp_hashinfo, skb, cb, r, bc);
  40 }
  41
  42 static int tcp_diag_dump_one(struct sk_buff *in_skb, const struct nlmsghdr *nlh,
  43                              struct inet_diag_req_v2 *req)
  44 {
  45         return inet_diag_dump_one_icsk(&tcp_hashinfo, in_skb, nlh, req);
  46 }
  47
  48 static const struct inet_diag_handler tcp_diag_handler = {
  49         .dump            = tcp_diag_dump,
  50         .dump_one        = tcp_diag_dump_one,
  51         .idiag_get_info  = tcp_diag_get_info,
  52         .idiag_type      = IPPROTO_TCP,
  53 };
  54
  55 static int __init tcp_diag_init(void)
  56 {
  57         return inet_diag_register(&tcp_diag_handler);
  58 }
  59
  60 static void __exit tcp_diag_exit(void)
  61 {
  62         inet_diag_unregister(&tcp_diag_handler);
  63 }
  64
  65 module_init(tcp_diag_init);
  66 module_exit(tcp_diag_exit);
  67 MODULE_LICENSE("GPL");
  68 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-6 /* AF_INET - IPPROTO_TCP */);