include/net/inet_timewait_sock.h

0001 /* SPDX-License-Identifier: GPL-2.0-or-later */
0002 /*
0003  * INET     An implementation of the TCP/IP protocol suite for the LINUX
0004  *      operating system.  INET is implemented using the  BSD Socket
0005  *      interface as the means of communication with the user level.
0006  *
0007  *      Definitions for a generic INET TIMEWAIT sock
0008  *
0009  *      From code originally in net/tcp.h
0010  */
0011 #ifndef _INET_TIMEWAIT_SOCK_
0012 #define _INET_TIMEWAIT_SOCK_
0013
0014 #include <linux/list.h>
0015 #include <linux/timer.h>
0016 #include <linux/types.h>
0017 #include <linux/workqueue.h>
0018
0019 #include <net/inet_sock.h>
0020 #include <net/sock.h>
0021 #include <net/tcp_states.h>
0022 #include <net/timewait_sock.h>
0023
0024 #include <linux/atomic.h>
0025
0026 struct inet_bind_bucket;
0027
0028 /*
0029  * This is a TIME_WAIT sock. It works around the memory consumption
0030  * problems of sockets in such a state on heavily loaded servers, but
0031  * without violating the protocol specification.
0032  */
0033 struct inet_timewait_sock {
0034     /*
0035      * Now struct sock also uses sock_common, so please just
0036      * don't add nothing before this first member (__tw_common) --acme
0037      */
0038     struct sock_common  __tw_common;
0039 #define tw_family       __tw_common.skc_family
0040 #define tw_state        __tw_common.skc_state
0041 #define tw_reuse        __tw_common.skc_reuse
0042 #define tw_reuseport        __tw_common.skc_reuseport
0043 #define tw_ipv6only     __tw_common.skc_ipv6only
0044 #define tw_bound_dev_if     __tw_common.skc_bound_dev_if
0045 #define tw_node         __tw_common.skc_nulls_node
0046 #define tw_bind_node        __tw_common.skc_bind_node
0047 #define tw_refcnt       __tw_common.skc_refcnt
0048 #define tw_hash         __tw_common.skc_hash
0049 #define tw_prot         __tw_common.skc_prot
0050 #define tw_net          __tw_common.skc_net
0051 #define tw_daddr            __tw_common.skc_daddr
0052 #define tw_v6_daddr     __tw_common.skc_v6_daddr
0053 #define tw_rcv_saddr        __tw_common.skc_rcv_saddr
0054 #define tw_v6_rcv_saddr     __tw_common.skc_v6_rcv_saddr
0055 #define tw_dport        __tw_common.skc_dport
0056 #define tw_num          __tw_common.skc_num
0057 #define tw_cookie       __tw_common.skc_cookie
0058 #define tw_dr           __tw_common.skc_tw_dr
0059
0060     __u32           tw_mark;
0061     volatile unsigned char  tw_substate;
0062     unsigned char       tw_rcv_wscale;
0063
0064     /* Socket demultiplex comparisons on incoming packets. */
0065     /* these three are in inet_sock */
0066     __be16          tw_sport;
0067     /* And these are ours. */
0068     unsigned int        tw_transparent  : 1,
0069                 tw_flowlabel    : 20,
0070                 tw_pad      : 3,    /* 3 bits hole */
0071                 tw_tos      : 8;
0072     u32         tw_txhash;
0073     u32         tw_priority;
0074     struct timer_list   tw_timer;
0075     struct inet_bind_bucket *tw_tb;
0076 };
0077 #define tw_tclass tw_tos
0078
0079 static inline struct inet_timewait_sock *inet_twsk(const struct sock *sk)
0080 {
0081     return (struct inet_timewait_sock *)sk;
0082 }
0083
0084 void inet_twsk_free(struct inet_timewait_sock *tw);
0085 void inet_twsk_put(struct inet_timewait_sock *tw);
0086
0087 void inet_twsk_bind_unhash(struct inet_timewait_sock *tw,
0088                struct inet_hashinfo *hashinfo);
0089
0090 struct inet_timewait_sock *inet_twsk_alloc(const struct sock *sk,
0091                        struct inet_timewait_death_row *dr,
0092                        const int state);
0093
0094 void inet_twsk_hashdance(struct inet_timewait_sock *tw, struct sock *sk,
0095              struct inet_hashinfo *hashinfo);
0096
0097 void __inet_twsk_schedule(struct inet_timewait_sock *tw, int timeo,
0098               bool rearm);
0099
0100 static inline void inet_twsk_schedule(struct inet_timewait_sock *tw, int timeo)
0101 {
0102     __inet_twsk_schedule(tw, timeo, false);
0103 }
0104
0105 static inline void inet_twsk_reschedule(struct inet_timewait_sock *tw, int timeo)
0106 {
0107     __inet_twsk_schedule(tw, timeo, true);
0108 }
0109
0110 void inet_twsk_deschedule_put(struct inet_timewait_sock *tw);
0111
0112 void inet_twsk_purge(struct inet_hashinfo *hashinfo, int family);
0113
0114 static inline
0115 struct net *twsk_net(const struct inet_timewait_sock *twsk)
0116 {
0117     return read_pnet(&twsk->tw_net);
0118 }
0119
0120 static inline
0121 void twsk_net_set(struct inet_timewait_sock *twsk, struct net *net)
0122 {
0123     write_pnet(&twsk->tw_net, net);
0124 }
0125 #endif  /* _INET_TIMEWAIT_SOCK_ */