include/net/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
  26 struct 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  */
  33 struct 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_kill         : 1,
  69                                 tw_transparent  : 1,
  70                                 tw_flowlabel    : 20,
  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 };
  78 #define tw_tclass tw_tos
  79
  80 static inline struct inet_timewait_sock *inet_twsk(const struct sock *sk)
  81 {
  82         return (struct inet_timewait_sock *)sk;
  83 }
  84
  85 void inet_twsk_free(struct inet_timewait_sock *tw);
  86 void inet_twsk_put(struct inet_timewait_sock *tw);
  87
  88 void inet_twsk_bind_unhash(struct inet_timewait_sock *tw,
  89                            struct inet_hashinfo *hashinfo);
  90
  91 struct inet_timewait_sock *inet_twsk_alloc(const struct sock *sk,
  92                                            struct inet_timewait_death_row *dr,
  93                                            const int state);
  94
  95 void inet_twsk_hashdance(struct inet_timewait_sock *tw, struct sock *sk,
  96                          struct inet_hashinfo *hashinfo);
  97
  98 void __inet_twsk_schedule(struct inet_timewait_sock *tw, int timeo,
  99                           bool rearm);
 100
 101 static inline void inet_twsk_schedule(struct inet_timewait_sock *tw, int timeo)
 102 {
 103         __inet_twsk_schedule(tw, timeo, false);
 104 }
 105
 106 static inline void inet_twsk_reschedule(struct inet_timewait_sock *tw, int timeo)
 107 {
 108         __inet_twsk_schedule(tw, timeo, true);
 109 }
 110
 111 void inet_twsk_deschedule_put(struct inet_timewait_sock *tw);
 112
 113 void inet_twsk_purge(struct inet_hashinfo *hashinfo, int family);
 114
 115 static inline
 116 struct net *twsk_net(const struct inet_timewait_sock *twsk)
 117 {
 118         return read_pnet(&twsk->tw_net);
 119 }
 120
 121 static inline
 122 void twsk_net_set(struct inet_timewait_sock *twsk, struct net *net)
 123 {
 124         write_pnet(&twsk->tw_net, net);
 125 }
 126 #endif  /* _INET_TIMEWAIT_SOCK_ */