1 /*
2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
5 *
6 * Definitions for a generic INET TIMEWAIT sock
7 *
8 * From code originally in net/tcp.h
9 *
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License
12 * as published by the Free Software Foundation; either version
13 * 2 of the License, or (at your option) any later version.
14 */
15 #ifndef _INET_TIMEWAIT_SOCK_
16 #define _INET_TIMEWAIT_SOCK_
17
18
19 #include <linux/kmemcheck.h>
20 #include <linux/list.h>
21 #include <linux/timer.h>
22 #include <linux/types.h>
23 #include <linux/workqueue.h>
24
25 #include <net/inet_sock.h>
26 #include <net/sock.h>
27 #include <net/tcp_states.h>
28 #include <net/timewait_sock.h>
29
30 #include <linux/atomic.h>
31
32 struct inet_hashinfo;
33
34 struct inet_timewait_death_row {
35 atomic_t tw_count;
36
37 struct inet_hashinfo *hashinfo ____cacheline_aligned_in_smp;
38 int sysctl_tw_recycle;
39 int sysctl_max_tw_buckets;
40 };
41
42 struct inet_bind_bucket;
43
44 /*
45 * This is a TIME_WAIT sock. It works around the memory consumption
46 * problems of sockets in such a state on heavily loaded servers, but
47 * without violating the protocol specification.
48 */
49 struct inet_timewait_sock {
50 /*
51 * Now struct sock also uses sock_common, so please just
52 * don't add nothing before this first member (__tw_common) --acme
53 */
54 struct sock_common __tw_common;
55 #define tw_family __tw_common.skc_family
56 #define tw_state __tw_common.skc_state
57 #define tw_reuse __tw_common.skc_reuse
58 #define tw_reuseport __tw_common.skc_reuseport
59 #define tw_ipv6only __tw_common.skc_ipv6only
60 #define tw_bound_dev_if __tw_common.skc_bound_dev_if
61 #define tw_node __tw_common.skc_nulls_node
62 #define tw_bind_node __tw_common.skc_bind_node
63 #define tw_refcnt __tw_common.skc_refcnt
64 #define tw_hash __tw_common.skc_hash
65 #define tw_prot __tw_common.skc_prot
66 #define tw_net __tw_common.skc_net
67 #define tw_daddr __tw_common.skc_daddr
68 #define tw_v6_daddr __tw_common.skc_v6_daddr
69 #define tw_rcv_saddr __tw_common.skc_rcv_saddr
70 #define tw_v6_rcv_saddr __tw_common.skc_v6_rcv_saddr
71 #define tw_dport __tw_common.skc_dport
72 #define tw_num __tw_common.skc_num
73 #define tw_cookie __tw_common.skc_cookie
74 #define tw_dr __tw_common.skc_tw_dr
75
76 int tw_timeout;
77 volatile unsigned char tw_substate;
78 unsigned char tw_rcv_wscale;
79
80 /* Socket demultiplex comparisons on incoming packets. */
81 /* these three are in inet_sock */
82 __be16 tw_sport;
83 kmemcheck_bitfield_begin(flags);
84 /* And these are ours. */
85 unsigned int tw_kill : 1,
86 tw_transparent : 1,
87 tw_flowlabel : 20,
88 tw_pad : 2, /* 2 bits hole */
89 tw_tos : 8;
90 kmemcheck_bitfield_end(flags);
91 struct timer_list tw_timer;
92 struct inet_bind_bucket *tw_tb;
93 };
94 #define tw_tclass tw_tos
95
inet_twsk(const struct sock * sk)96 static inline struct inet_timewait_sock *inet_twsk(const struct sock *sk)
97 {
98 return (struct inet_timewait_sock *)sk;
99 }
100
101 void inet_twsk_free(struct inet_timewait_sock *tw);
102 void inet_twsk_put(struct inet_timewait_sock *tw);
103
104 void inet_twsk_bind_unhash(struct inet_timewait_sock *tw,
105 struct inet_hashinfo *hashinfo);
106
107 struct inet_timewait_sock *inet_twsk_alloc(const struct sock *sk,
108 struct inet_timewait_death_row *dr,
109 const int state);
110
111 void __inet_twsk_hashdance(struct inet_timewait_sock *tw, struct sock *sk,
112 struct inet_hashinfo *hashinfo);
113
114 void __inet_twsk_schedule(struct inet_timewait_sock *tw, int timeo,
115 bool rearm);
116
inet_twsk_schedule(struct inet_timewait_sock * tw,int timeo)117 static inline void inet_twsk_schedule(struct inet_timewait_sock *tw, int timeo)
118 {
119 __inet_twsk_schedule(tw, timeo, false);
120 }
121
inet_twsk_reschedule(struct inet_timewait_sock * tw,int timeo)122 static inline void inet_twsk_reschedule(struct inet_timewait_sock *tw, int timeo)
123 {
124 __inet_twsk_schedule(tw, timeo, true);
125 }
126
127 void inet_twsk_deschedule_put(struct inet_timewait_sock *tw);
128
129 void inet_twsk_purge(struct inet_hashinfo *hashinfo,
130 struct inet_timewait_death_row *twdr, int family);
131
132 static inline
twsk_net(const struct inet_timewait_sock * twsk)133 struct net *twsk_net(const struct inet_timewait_sock *twsk)
134 {
135 return read_pnet(&twsk->tw_net);
136 }
137
138 static inline
twsk_net_set(struct inet_timewait_sock * twsk,struct net * net)139 void twsk_net_set(struct inet_timewait_sock *twsk, struct net *net)
140 {
141 write_pnet(&twsk->tw_net, net);
142 }
143 #endif /* _INET_TIMEWAIT_SOCK_ */
144