236 lines
		
	
	
		
			6.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			236 lines
		
	
	
		
			6.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
 | |
|  * INET		An implementation of the TCP/IP protocol suite for the LINUX
 | |
|  *		operating system.  INET is implemented using the  BSD Socket
 | |
|  *		interface as the means of communication with the user level.
 | |
|  *
 | |
|  *		Definitions for a generic INET TIMEWAIT sock
 | |
|  *
 | |
|  *		From code originally in net/tcp.h
 | |
|  *
 | |
|  *		This program is free software; you can redistribute it and/or
 | |
|  *		modify it under the terms of the GNU General Public License
 | |
|  *		as published by the Free Software Foundation; either version
 | |
|  *		2 of the License, or (at your option) any later version.
 | |
|  */
 | |
| #ifndef _INET_TIMEWAIT_SOCK_
 | |
| #define _INET_TIMEWAIT_SOCK_
 | |
| 
 | |
| 
 | |
| #include <linux/kmemcheck.h>
 | |
| #include <linux/list.h>
 | |
| #include <linux/module.h>
 | |
| #include <linux/timer.h>
 | |
| #include <linux/types.h>
 | |
| #include <linux/workqueue.h>
 | |
| 
 | |
| #include <net/inet_sock.h>
 | |
| #include <net/sock.h>
 | |
| #include <net/tcp_states.h>
 | |
| #include <net/timewait_sock.h>
 | |
| 
 | |
| #include <asm/atomic.h>
 | |
| 
 | |
| struct inet_hashinfo;
 | |
| 
 | |
| #define INET_TWDR_RECYCLE_SLOTS_LOG	5
 | |
| #define INET_TWDR_RECYCLE_SLOTS		(1 << INET_TWDR_RECYCLE_SLOTS_LOG)
 | |
| 
 | |
| /*
 | |
|  * If time > 4sec, it is "slow" path, no recycling is required,
 | |
|  * so that we select tick to get range about 4 seconds.
 | |
|  */
 | |
| #if HZ <= 16 || HZ > 4096
 | |
| # error Unsupported: HZ <= 16 or HZ > 4096
 | |
| #elif HZ <= 32
 | |
| # define INET_TWDR_RECYCLE_TICK (5 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
 | |
| #elif HZ <= 64
 | |
| # define INET_TWDR_RECYCLE_TICK (6 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
 | |
| #elif HZ <= 128
 | |
| # define INET_TWDR_RECYCLE_TICK (7 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
 | |
| #elif HZ <= 256
 | |
| # define INET_TWDR_RECYCLE_TICK (8 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
 | |
| #elif HZ <= 512
 | |
| # define INET_TWDR_RECYCLE_TICK (9 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
 | |
| #elif HZ <= 1024
 | |
| # define INET_TWDR_RECYCLE_TICK (10 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
 | |
| #elif HZ <= 2048
 | |
| # define INET_TWDR_RECYCLE_TICK (11 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
 | |
| #else
 | |
| # define INET_TWDR_RECYCLE_TICK (12 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
 | |
| #endif
 | |
| 
 | |
| /* TIME_WAIT reaping mechanism. */
 | |
| #define INET_TWDR_TWKILL_SLOTS	8 /* Please keep this a power of 2. */
 | |
| 
 | |
| #define INET_TWDR_TWKILL_QUOTA 100
 | |
| 
 | |
| struct inet_timewait_death_row {
 | |
| 	/* Short-time timewait calendar */
 | |
| 	int			twcal_hand;
 | |
| 	unsigned long		twcal_jiffie;
 | |
| 	struct timer_list	twcal_timer;
 | |
| 	struct hlist_head	twcal_row[INET_TWDR_RECYCLE_SLOTS];
 | |
| 
 | |
| 	spinlock_t		death_lock;
 | |
| 	int			tw_count;
 | |
| 	int			period;
 | |
| 	u32			thread_slots;
 | |
| 	struct work_struct	twkill_work;
 | |
| 	struct timer_list	tw_timer;
 | |
| 	int			slot;
 | |
| 	struct hlist_head	cells[INET_TWDR_TWKILL_SLOTS];
 | |
| 	struct inet_hashinfo 	*hashinfo;
 | |
| 	int			sysctl_tw_recycle;
 | |
| 	int			sysctl_max_tw_buckets;
 | |
| };
 | |
| 
 | |
| extern void inet_twdr_hangman(unsigned long data);
 | |
| extern void inet_twdr_twkill_work(struct work_struct *work);
 | |
| extern void inet_twdr_twcal_tick(unsigned long data);
 | |
| 
 | |
| #if (BITS_PER_LONG == 64)
 | |
| #define INET_TIMEWAIT_ADDRCMP_ALIGN_BYTES 8
 | |
| #else
 | |
| #define INET_TIMEWAIT_ADDRCMP_ALIGN_BYTES 4
 | |
| #endif
 | |
| 
 | |
| struct inet_bind_bucket;
 | |
| 
 | |
| /*
 | |
|  * This is a TIME_WAIT sock. It works around the memory consumption
 | |
|  * problems of sockets in such a state on heavily loaded servers, but
 | |
|  * without violating the protocol specification.
 | |
|  */
 | |
| struct inet_timewait_sock {
 | |
| 	/*
 | |
| 	 * Now struct sock also uses sock_common, so please just
 | |
| 	 * don't add nothing before this first member (__tw_common) --acme
 | |
| 	 */
 | |
| 	struct sock_common	__tw_common;
 | |
| #define tw_family		__tw_common.skc_family
 | |
| #define tw_state		__tw_common.skc_state
 | |
| #define tw_reuse		__tw_common.skc_reuse
 | |
| #define tw_bound_dev_if		__tw_common.skc_bound_dev_if
 | |
| #define tw_node			__tw_common.skc_nulls_node
 | |
| #define tw_bind_node		__tw_common.skc_bind_node
 | |
| #define tw_refcnt		__tw_common.skc_refcnt
 | |
| #define tw_hash			__tw_common.skc_hash
 | |
| #define tw_prot			__tw_common.skc_prot
 | |
| #define tw_net			__tw_common.skc_net
 | |
| 	int			tw_timeout;
 | |
| 	volatile unsigned char	tw_substate;
 | |
| 	/* 3 bits hole, try to pack */
 | |
| 	unsigned char		tw_rcv_wscale;
 | |
| 	/* Socket demultiplex comparisons on incoming packets. */
 | |
| 	/* these five are in inet_sock */
 | |
| 	__be16			tw_sport;
 | |
| 	__be32			tw_daddr __attribute__((aligned(INET_TIMEWAIT_ADDRCMP_ALIGN_BYTES)));
 | |
| 	__be32			tw_rcv_saddr;
 | |
| 	__be16			tw_dport;
 | |
| 	__u16			tw_num;
 | |
| 	kmemcheck_bitfield_begin(flags);
 | |
| 	/* And these are ours. */
 | |
| 	unsigned int		tw_ipv6only     : 1,
 | |
| 				tw_transparent  : 1,
 | |
| 				tw_pad		: 14,	/* 14 bits hole */
 | |
| 				tw_ipv6_offset  : 16;
 | |
| 	kmemcheck_bitfield_end(flags);
 | |
| 	unsigned long		tw_ttd;
 | |
| 	struct inet_bind_bucket	*tw_tb;
 | |
| 	struct hlist_node	tw_death_node;
 | |
| };
 | |
| 
 | |
| static inline void inet_twsk_add_node_rcu(struct inet_timewait_sock *tw,
 | |
| 				      struct hlist_nulls_head *list)
 | |
| {
 | |
| 	hlist_nulls_add_head_rcu(&tw->tw_node, list);
 | |
| }
 | |
| 
 | |
| static inline void inet_twsk_add_bind_node(struct inet_timewait_sock *tw,
 | |
| 					   struct hlist_head *list)
 | |
| {
 | |
| 	hlist_add_head(&tw->tw_bind_node, list);
 | |
| }
 | |
| 
 | |
| static inline int inet_twsk_dead_hashed(const struct inet_timewait_sock *tw)
 | |
| {
 | |
| 	return !hlist_unhashed(&tw->tw_death_node);
 | |
| }
 | |
| 
 | |
| static inline void inet_twsk_dead_node_init(struct inet_timewait_sock *tw)
 | |
| {
 | |
| 	tw->tw_death_node.pprev = NULL;
 | |
| }
 | |
| 
 | |
| static inline void __inet_twsk_del_dead_node(struct inet_timewait_sock *tw)
 | |
| {
 | |
| 	__hlist_del(&tw->tw_death_node);
 | |
| 	inet_twsk_dead_node_init(tw);
 | |
| }
 | |
| 
 | |
| static inline int inet_twsk_del_dead_node(struct inet_timewait_sock *tw)
 | |
| {
 | |
| 	if (inet_twsk_dead_hashed(tw)) {
 | |
| 		__inet_twsk_del_dead_node(tw);
 | |
| 		return 1;
 | |
| 	}
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| #define inet_twsk_for_each(tw, node, head) \
 | |
| 	hlist_nulls_for_each_entry(tw, node, head, tw_node)
 | |
| 
 | |
| #define inet_twsk_for_each_inmate(tw, node, jail) \
 | |
| 	hlist_for_each_entry(tw, node, jail, tw_death_node)
 | |
| 
 | |
| #define inet_twsk_for_each_inmate_safe(tw, node, safe, jail) \
 | |
| 	hlist_for_each_entry_safe(tw, node, safe, jail, tw_death_node)
 | |
| 
 | |
| static inline struct inet_timewait_sock *inet_twsk(const struct sock *sk)
 | |
| {
 | |
| 	return (struct inet_timewait_sock *)sk;
 | |
| }
 | |
| 
 | |
| static inline __be32 inet_rcv_saddr(const struct sock *sk)
 | |
| {
 | |
| 	return likely(sk->sk_state != TCP_TIME_WAIT) ?
 | |
| 		inet_sk(sk)->rcv_saddr : inet_twsk(sk)->tw_rcv_saddr;
 | |
| }
 | |
| 
 | |
| extern void inet_twsk_put(struct inet_timewait_sock *tw);
 | |
| 
 | |
| extern struct inet_timewait_sock *inet_twsk_alloc(const struct sock *sk,
 | |
| 						  const int state);
 | |
| 
 | |
| extern void __inet_twsk_hashdance(struct inet_timewait_sock *tw,
 | |
| 				  struct sock *sk,
 | |
| 				  struct inet_hashinfo *hashinfo);
 | |
| 
 | |
| extern void inet_twsk_schedule(struct inet_timewait_sock *tw,
 | |
| 			       struct inet_timewait_death_row *twdr,
 | |
| 			       const int timeo, const int timewait_len);
 | |
| extern void inet_twsk_deschedule(struct inet_timewait_sock *tw,
 | |
| 				 struct inet_timewait_death_row *twdr);
 | |
| 
 | |
| extern void inet_twsk_purge(struct net *net, struct inet_hashinfo *hashinfo,
 | |
| 			    struct inet_timewait_death_row *twdr, int family);
 | |
| 
 | |
| static inline
 | |
| struct net *twsk_net(const struct inet_timewait_sock *twsk)
 | |
| {
 | |
| #ifdef CONFIG_NET_NS
 | |
| 	return twsk->tw_net;
 | |
| #else
 | |
| 	return &init_net;
 | |
| #endif
 | |
| }
 | |
| 
 | |
| static inline
 | |
| void twsk_net_set(struct inet_timewait_sock *twsk, struct net *net)
 | |
| {
 | |
| #ifdef CONFIG_NET_NS
 | |
| 	twsk->tw_net = net;
 | |
| #endif
 | |
| }
 | |
| #endif	/* _INET_TIMEWAIT_SOCK_ */
 |