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/net.h>
  14 #include <linux/sock_diag.h>
  15 #include <linux/inet_diag.h>
  16
  17 #include <linux/tcp.h>
  18
  19 #include <net/tcp.h>
  20
  21 static void tcp_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
  22                               void *_info)
  23 {
  24         struct tcp_info *info = _info;
  25
  26         if (sk_state_load(sk) == TCP_LISTEN) {
  27                 r->idiag_rqueue = sk->sk_ack_backlog;
  28                 r->idiag_wqueue = sk->sk_max_ack_backlog;
  29         } else if (sk->sk_type == SOCK_STREAM) {
  30                 const struct tcp_sock *tp = tcp_sk(sk);
  31
  32                 r->idiag_rqueue = max_t(int, tp->rcv_nxt - tp->copied_seq, 0);
  33                 r->idiag_wqueue = tp->write_seq - tp->snd_una;
  34         }
  35         if (info)
  36                 tcp_get_info(sk, info);
  37 }
  38
  39 static void tcp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
  40                           const struct inet_diag_req_v2 *r, struct nlattr *bc)
  41 {
  42         inet_diag_dump_icsk(&tcp_hashinfo, skb, cb, r, bc);
  43 }
  44
  45 static int tcp_diag_dump_one(struct sk_buff *in_skb, const struct nlmsghdr *nlh,
  46                              const struct inet_diag_req_v2 *req)
  47 {
  48         return inet_diag_dump_one_icsk(&tcp_hashinfo, in_skb, nlh, req);
  49 }
  50
  51 #ifdef CONFIG_INET_DIAG_DESTROY
  52 static int tcp_diag_destroy(struct sk_buff *in_skb,
  53                             const struct inet_diag_req_v2 *req)
  54 {
  55         struct net *net = sock_net(in_skb->sk);
  56         struct sock *sk = inet_diag_find_one_icsk(net, &tcp_hashinfo, req);
  57         int err;
  58
  59         if (IS_ERR(sk))
  60                 return PTR_ERR(sk);
  61
  62         err = sock_diag_destroy(sk, ECONNABORTED);
  63
  64         sock_gen_put(sk);
  65
  66         return err;
  67 }
  68 #endif
  69
  70 static const struct inet_diag_handler tcp_diag_handler = {
  71         .dump            = tcp_diag_dump,
  72         .dump_one        = tcp_diag_dump_one,
  73         .idiag_get_info  = tcp_diag_get_info,
  74         .idiag_type      = IPPROTO_TCP,
  75         .idiag_info_size = sizeof(struct tcp_info),
  76 #ifdef CONFIG_INET_DIAG_DESTROY
  77         .destroy         = tcp_diag_destroy,
  78 #endif
  79 };
  80
  81 static int __init tcp_diag_init(void)
  82 {
  83         return inet_diag_register(&tcp_diag_handler);
  84 }
  85
  86 static void __exit tcp_diag_exit(void)
  87 {
  88         inet_diag_unregister(&tcp_diag_handler);
  89 }
  90
  91 module_init(tcp_diag_init);
  92 module_exit(tcp_diag_exit);
  93 MODULE_LICENSE("GPL");
  94 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-6 /* AF_INET - IPPROTO_TCP */);