inet_timewait_sock.h

  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_tx_queue_mapping	__tw_common.skc_tx_queue_mapping
 49#define tw_rx_queue_mapping	__tw_common.skc_rx_queue_mapping
 50#define tw_hash			__tw_common.skc_hash
 51#define tw_prot			__tw_common.skc_prot
 52#define tw_net			__tw_common.skc_net
 53#define tw_daddr        	__tw_common.skc_daddr
 54#define tw_v6_daddr		__tw_common.skc_v6_daddr
 55#define tw_rcv_saddr    	__tw_common.skc_rcv_saddr
 56#define tw_v6_rcv_saddr    	__tw_common.skc_v6_rcv_saddr
 57#define tw_dport		__tw_common.skc_dport
 58#define tw_num			__tw_common.skc_num
 59#define tw_cookie		__tw_common.skc_cookie
 60#define tw_dr			__tw_common.skc_tw_dr
 61
 62	__u32			tw_mark;
 63	unsigned char		tw_substate;
 64	unsigned char		tw_rcv_wscale;
 65
 66	/* Socket demultiplex comparisons on incoming packets. */
 67	/* these three are in inet_sock */
 68	__be16			tw_sport;
 69	/* And these are ours. */
 70	unsigned int		tw_transparent  : 1,
 71				tw_flowlabel	: 20,
 72				tw_usec_ts	: 1,
 73				tw_connect_bind	: 1,
 74				tw_pad		: 1,	/* 1 bit hole */
 75				tw_tos		: 8;
 76	u32			tw_txhash;
 77	u32			tw_priority;
 78	/**
 79	 * @tw_reuse_stamp: Time of entry into %TCP_TIME_WAIT state in msec.
 80	 */
 81	u32			tw_entry_stamp;
 82	struct timer_list	tw_timer;
 83	struct inet_bind_bucket	*tw_tb;
 84	struct inet_bind2_bucket	*tw_tb2;
 85#if IS_ENABLED(CONFIG_INET_PSP)
 86	struct psp_assoc __rcu	  *psp_assoc;
 87#endif
 88#ifdef CONFIG_SOCK_VALIDATE_XMIT
 89	struct sk_buff*		(*tw_validate_xmit_skb)(struct sock *sk,
 90							struct net_device *dev,
 91							struct sk_buff *skb);
 92#endif
 93};
 94#define tw_tclass tw_tos
 95
 96static inline struct inet_timewait_sock *inet_twsk(const struct sock *sk)
 97{
 98	return (struct inet_timewait_sock *)sk;
 99}
100
101void inet_twsk_free(struct inet_timewait_sock *tw);
102void inet_twsk_put(struct inet_timewait_sock *tw);
103
104void inet_twsk_bind_unhash(struct inet_timewait_sock *tw,
105			   struct inet_hashinfo *hashinfo);
106
107struct inet_timewait_sock *inet_twsk_alloc(const struct sock *sk,
108					   struct inet_timewait_death_row *dr,
109					   const int state);
110
111void inet_twsk_hashdance_schedule(struct inet_timewait_sock *tw,
112				  struct sock *sk,
113				  struct inet_hashinfo *hashinfo,
114				  int timeo);
115
116void __inet_twsk_schedule(struct inet_timewait_sock *tw, int timeo,
117			  bool rearm);
118
119static inline void inet_twsk_reschedule(struct inet_timewait_sock *tw, int timeo)
120{
121	__inet_twsk_schedule(tw, timeo, true);
122}
123
124void inet_twsk_deschedule_put(struct inet_timewait_sock *tw);
125
126void inet_twsk_purge(struct inet_hashinfo *hashinfo);
127
128static inline
129struct net *twsk_net(const struct inet_timewait_sock *twsk)
130{
131	return read_pnet(&twsk->tw_net);
132}
133
134static inline
135void twsk_net_set(struct inet_timewait_sock *twsk, struct net *net)
136{
137	write_pnet(&twsk->tw_net, net);
138}
139#endif	/* _INET_TIMEWAIT_SOCK_ */