1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 * INET An implementation of the TCP/IP protocol suite for the LINUX
4 * operating system. INET is implemented using the BSD Socket
5 * interface as the means of communication with the user level.
6 *
7 * Definitions for a generic INET TIMEWAIT sock
8 *
9 * From code originally in net/tcp.h
10 */
11#ifndef _INET_TIMEWAIT_SOCK_
12#define _INET_TIMEWAIT_SOCK_
13
14#include <linux/list.h>
15#include <linux/timer.h>
16#include <linux/types.h>
17#include <linux/workqueue.h>
18
19#include <net/inet_sock.h>
20#include <net/sock.h>
21#include <net/tcp_states.h>
22#include <net/timewait_sock.h>
23
24#include <linux/atomic.h>
25
26struct inet_bind_bucket;
27
28/*
29 * This is a TIME_WAIT sock. It works around the memory consumption
30 * problems of sockets in such a state on heavily loaded servers, but
31 * without violating the protocol specification.
32 */
33struct inet_timewait_sock {
34 /*
35 * Now struct sock also uses sock_common, so please just
36 * don't add nothing before this first member (__tw_common) --acme
37 */
38 struct sock_common __tw_common;
39#define tw_family __tw_common.skc_family
40#define tw_state __tw_common.skc_state
41#define tw_reuse __tw_common.skc_reuse
42#define tw_reuseport __tw_common.skc_reuseport
43#define tw_ipv6only __tw_common.skc_ipv6only
44#define tw_bound_dev_if __tw_common.skc_bound_dev_if
45#define tw_node __tw_common.skc_nulls_node
46#define tw_bind_node __tw_common.skc_bind_node
47#define tw_refcnt __tw_common.skc_refcnt
48#define tw_hash __tw_common.skc_hash
49#define tw_prot __tw_common.skc_prot
50#define tw_net __tw_common.skc_net
51#define tw_daddr __tw_common.skc_daddr
52#define tw_v6_daddr __tw_common.skc_v6_daddr
53#define tw_rcv_saddr __tw_common.skc_rcv_saddr
54#define tw_v6_rcv_saddr __tw_common.skc_v6_rcv_saddr
55#define tw_dport __tw_common.skc_dport
56#define tw_num __tw_common.skc_num
57#define tw_cookie __tw_common.skc_cookie
58#define tw_dr __tw_common.skc_tw_dr
59
60 __u32 tw_mark;
61 volatile unsigned char tw_substate;
62 unsigned char tw_rcv_wscale;
63
64 /* Socket demultiplex comparisons on incoming packets. */
65 /* these three are in inet_sock */
66 __be16 tw_sport;
67 /* And these are ours. */
68 unsigned int tw_transparent : 1,
69 tw_flowlabel : 20,
70 tw_usec_ts : 1,
71 tw_pad : 2, /* 2 bits hole */
72 tw_tos : 8;
73 u32 tw_txhash;
74 u32 tw_priority;
75 struct timer_list tw_timer;
76 struct inet_bind_bucket *tw_tb;
77 struct inet_bind2_bucket *tw_tb2;
78};
79#define tw_tclass tw_tos
80
81static inline struct inet_timewait_sock *inet_twsk(const struct sock *sk)
82{
83 return (struct inet_timewait_sock *)sk;
84}
85
86void inet_twsk_free(struct inet_timewait_sock *tw);
87void inet_twsk_put(struct inet_timewait_sock *tw);
88
89void inet_twsk_bind_unhash(struct inet_timewait_sock *tw,
90 struct inet_hashinfo *hashinfo);
91
92struct inet_timewait_sock *inet_twsk_alloc(const struct sock *sk,
93 struct inet_timewait_death_row *dr,
94 const int state);
95
96void inet_twsk_hashdance(struct inet_timewait_sock *tw, struct sock *sk,
97 struct inet_hashinfo *hashinfo);
98
99void __inet_twsk_schedule(struct inet_timewait_sock *tw, int timeo,
100 bool rearm);
101
102static inline void inet_twsk_schedule(struct inet_timewait_sock *tw, int timeo)
103{
104 __inet_twsk_schedule(tw, timeo, rearm: false);
105}
106
107static inline void inet_twsk_reschedule(struct inet_timewait_sock *tw, int timeo)
108{
109 __inet_twsk_schedule(tw, timeo, rearm: true);
110}
111
112void inet_twsk_deschedule_put(struct inet_timewait_sock *tw);
113
114void inet_twsk_purge(struct inet_hashinfo *hashinfo, int family);
115
116static inline
117struct net *twsk_net(const struct inet_timewait_sock *twsk)
118{
119 return read_pnet(pnet: &twsk->tw_net);
120}
121
122static inline
123void twsk_net_set(struct inet_timewait_sock *twsk, struct net *net)
124{
125 write_pnet(pnet: &twsk->tw_net, net);
126}
127#endif /* _INET_TIMEWAIT_SOCK_ */
128

source code of linux/include/net/inet_timewait_sock.h