2 * NET Generic infrastructure for INET connection oriented protocols.
4 * Definitions for inet_connection_sock
6 * Authors: Many people, see the TCP sources
8 * From code originally in TCP
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.
15 #ifndef _INET_CONNECTION_SOCK_H
16 #define _INET_CONNECTION_SOCK_H
18 #include <linux/compiler.h>
19 #include <linux/string.h>
20 #include <linux/timer.h>
21 #include <linux/poll.h>
23 #include <net/inet_sock.h>
24 #include <net/request_sock.h>
26 #define INET_CSK_DEBUG 1
28 /* Cancel timers, when they are not required. */
29 #undef INET_CSK_CLEAR_TIMERS
31 struct inet_bind_bucket;
32 struct tcp_congestion_ops;
35 * Pointers to address related TCP functions
36 * (i.e. things that depend on the address family)
38 struct inet_connection_sock_af_ops {
39 int (*queue_xmit)(struct sock *sk, struct sk_buff *skb, struct flowi *fl);
40 void (*send_check)(struct sock *sk, struct sk_buff *skb);
41 int (*rebuild_header)(struct sock *sk);
42 void (*sk_rx_dst_set)(struct sock *sk, const struct sk_buff *skb);
43 int (*conn_request)(struct sock *sk, struct sk_buff *skb);
44 struct sock *(*syn_recv_sock)(const struct sock *sk, struct sk_buff *skb,
45 struct request_sock *req,
46 struct dst_entry *dst,
47 struct request_sock *req_unhash,
50 u16 net_frag_header_len;
52 int (*setsockopt)(struct sock *sk, int level, int optname,
53 char __user *optval, unsigned int optlen);
54 int (*getsockopt)(struct sock *sk, int level, int optname,
55 char __user *optval, int __user *optlen);
57 int (*compat_setsockopt)(struct sock *sk,
58 int level, int optname,
59 char __user *optval, unsigned int optlen);
60 int (*compat_getsockopt)(struct sock *sk,
61 int level, int optname,
62 char __user *optval, int __user *optlen);
64 void (*addr2sockaddr)(struct sock *sk, struct sockaddr *);
65 int (*bind_conflict)(const struct sock *sk,
66 const struct inet_bind_bucket *tb,
67 bool relax, bool soreuseport_ok);
68 void (*mtu_reduced)(struct sock *sk);
71 /** inet_connection_sock - INET connection oriented sock
73 * @icsk_accept_queue: FIFO of established children
74 * @icsk_bind_hash: Bind node
75 * @icsk_timeout: Timeout
76 * @icsk_retransmit_timer: Resend (no ack)
77 * @icsk_rto: Retransmit timeout
78 * @icsk_pmtu_cookie Last pmtu seen by socket
79 * @icsk_ca_ops Pluggable congestion control hook
80 * @icsk_af_ops Operations which are AF_INET{4,6} specific
81 * @icsk_ca_state: Congestion control state
82 * @icsk_retransmits: Number of unrecovered [RTO] timeouts
83 * @icsk_pending: Scheduled timer event
84 * @icsk_backoff: Backoff
85 * @icsk_syn_retries: Number of allowed SYN (or equivalent) retries
86 * @icsk_probes_out: unanswered 0 window probes
87 * @icsk_ext_hdr_len: Network protocol overhead (IP/IPv6 options)
88 * @icsk_ack: Delayed ACK control data
89 * @icsk_mtup; MTU probing control data
91 struct inet_connection_sock {
92 /* inet_sock has to be the first member! */
93 struct inet_sock icsk_inet;
94 struct request_sock_queue icsk_accept_queue;
95 struct inet_bind_bucket *icsk_bind_hash;
96 unsigned long icsk_timeout;
97 struct timer_list icsk_retransmit_timer;
98 struct timer_list icsk_delack_timer;
100 __u32 icsk_pmtu_cookie;
101 const struct tcp_congestion_ops *icsk_ca_ops;
102 const struct inet_connection_sock_af_ops *icsk_af_ops;
103 unsigned int (*icsk_sync_mss)(struct sock *sk, u32 pmtu);
104 __u8 icsk_ca_state:6,
105 icsk_ca_setsockopt:1,
106 icsk_ca_dst_locked:1;
107 __u8 icsk_retransmits;
110 __u8 icsk_syn_retries;
111 __u8 icsk_probes_out;
112 __u16 icsk_ext_hdr_len;
114 __u8 pending; /* ACK is pending */
115 __u8 quick; /* Scheduled number of quick acks */
116 __u8 pingpong; /* The session is interactive */
117 __u8 blocked; /* Delayed ACK was blocked by socket lock */
118 __u32 ato; /* Predicted tick of soft clock */
119 unsigned long timeout; /* Currently scheduled timeout */
120 __u32 lrcvtime; /* timestamp of last received data packet */
121 __u16 last_seg_size; /* Size of last incoming segment */
122 __u16 rcv_mss; /* MSS used for delayed ACK decisions */
127 /* Range of MTUs to search */
131 /* Information on the current probe. */
136 u32 icsk_user_timeout;
138 u64 icsk_ca_priv[88 / sizeof(u64)];
139 #define ICSK_CA_PRIV_SIZE (11 * sizeof(u64))
142 #define ICSK_TIME_RETRANS 1 /* Retransmit timer */
143 #define ICSK_TIME_DACK 2 /* Delayed ack timer */
144 #define ICSK_TIME_PROBE0 3 /* Zero window probe timer */
145 #define ICSK_TIME_EARLY_RETRANS 4 /* Early retransmit timer */
146 #define ICSK_TIME_LOSS_PROBE 5 /* Tail loss probe timer */
148 static inline struct inet_connection_sock *inet_csk(const struct sock *sk)
150 return (struct inet_connection_sock *)sk;
153 static inline void *inet_csk_ca(const struct sock *sk)
155 return (void *)inet_csk(sk)->icsk_ca_priv;
158 struct sock *inet_csk_clone_lock(const struct sock *sk,
159 const struct request_sock *req,
160 const gfp_t priority);
162 enum inet_csk_ack_state_t {
169 void inet_csk_init_xmit_timers(struct sock *sk,
170 void (*retransmit_handler)(unsigned long),
171 void (*delack_handler)(unsigned long),
172 void (*keepalive_handler)(unsigned long));
173 void inet_csk_clear_xmit_timers(struct sock *sk);
175 static inline void inet_csk_schedule_ack(struct sock *sk)
177 inet_csk(sk)->icsk_ack.pending |= ICSK_ACK_SCHED;
180 static inline int inet_csk_ack_scheduled(const struct sock *sk)
182 return inet_csk(sk)->icsk_ack.pending & ICSK_ACK_SCHED;
185 static inline void inet_csk_delack_init(struct sock *sk)
187 memset(&inet_csk(sk)->icsk_ack, 0, sizeof(inet_csk(sk)->icsk_ack));
190 void inet_csk_delete_keepalive_timer(struct sock *sk);
191 void inet_csk_reset_keepalive_timer(struct sock *sk, unsigned long timeout);
193 #ifdef INET_CSK_DEBUG
194 extern const char inet_csk_timer_bug_msg[];
197 static inline void inet_csk_clear_xmit_timer(struct sock *sk, const int what)
199 struct inet_connection_sock *icsk = inet_csk(sk);
201 if (what == ICSK_TIME_RETRANS || what == ICSK_TIME_PROBE0) {
202 icsk->icsk_pending = 0;
203 #ifdef INET_CSK_CLEAR_TIMERS
204 sk_stop_timer(sk, &icsk->icsk_retransmit_timer);
206 } else if (what == ICSK_TIME_DACK) {
207 icsk->icsk_ack.blocked = icsk->icsk_ack.pending = 0;
208 #ifdef INET_CSK_CLEAR_TIMERS
209 sk_stop_timer(sk, &icsk->icsk_delack_timer);
212 #ifdef INET_CSK_DEBUG
214 pr_debug("%s", inet_csk_timer_bug_msg);
220 * Reset the retransmission timer
222 static inline void inet_csk_reset_xmit_timer(struct sock *sk, const int what,
224 const unsigned long max_when)
226 struct inet_connection_sock *icsk = inet_csk(sk);
228 if (when > max_when) {
229 #ifdef INET_CSK_DEBUG
230 pr_debug("reset_xmit_timer: sk=%p %d when=0x%lx, caller=%p\n",
231 sk, what, when, current_text_addr());
236 if (what == ICSK_TIME_RETRANS || what == ICSK_TIME_PROBE0 ||
237 what == ICSK_TIME_EARLY_RETRANS || what == ICSK_TIME_LOSS_PROBE) {
238 icsk->icsk_pending = what;
239 icsk->icsk_timeout = jiffies + when;
240 sk_reset_timer(sk, &icsk->icsk_retransmit_timer, icsk->icsk_timeout);
241 } else if (what == ICSK_TIME_DACK) {
242 icsk->icsk_ack.pending |= ICSK_ACK_TIMER;
243 icsk->icsk_ack.timeout = jiffies + when;
244 sk_reset_timer(sk, &icsk->icsk_delack_timer, icsk->icsk_ack.timeout);
246 #ifdef INET_CSK_DEBUG
248 pr_debug("%s", inet_csk_timer_bug_msg);
253 static inline unsigned long
254 inet_csk_rto_backoff(const struct inet_connection_sock *icsk,
255 unsigned long max_when)
257 u64 when = (u64)icsk->icsk_rto << icsk->icsk_backoff;
259 return (unsigned long)min_t(u64, when, max_when);
262 struct sock *inet_csk_accept(struct sock *sk, int flags, int *err);
264 int inet_csk_bind_conflict(const struct sock *sk,
265 const struct inet_bind_bucket *tb, bool relax,
266 bool soreuseport_ok);
267 int inet_csk_get_port(struct sock *sk, unsigned short snum);
269 struct dst_entry *inet_csk_route_req(const struct sock *sk, struct flowi4 *fl4,
270 const struct request_sock *req);
271 struct dst_entry *inet_csk_route_child_sock(const struct sock *sk,
273 const struct request_sock *req);
275 struct sock *inet_csk_reqsk_queue_add(struct sock *sk,
276 struct request_sock *req,
278 void inet_csk_reqsk_queue_hash_add(struct sock *sk, struct request_sock *req,
279 unsigned long timeout);
280 struct sock *inet_csk_complete_hashdance(struct sock *sk, struct sock *child,
281 struct request_sock *req,
284 static inline void inet_csk_reqsk_queue_added(struct sock *sk)
286 reqsk_queue_added(&inet_csk(sk)->icsk_accept_queue);
289 static inline int inet_csk_reqsk_queue_len(const struct sock *sk)
291 return reqsk_queue_len(&inet_csk(sk)->icsk_accept_queue);
294 static inline int inet_csk_reqsk_queue_is_full(const struct sock *sk)
296 return inet_csk_reqsk_queue_len(sk) >= sk->sk_max_ack_backlog;
299 void inet_csk_reqsk_queue_drop(struct sock *sk, struct request_sock *req);
300 void inet_csk_reqsk_queue_drop_and_put(struct sock *sk, struct request_sock *req);
302 void inet_csk_destroy_sock(struct sock *sk);
303 void inet_csk_prepare_forced_close(struct sock *sk);
306 * LISTEN is a special case for poll..
308 static inline unsigned int inet_csk_listen_poll(const struct sock *sk)
310 return !reqsk_queue_empty(&inet_csk(sk)->icsk_accept_queue) ?
311 (POLLIN | POLLRDNORM) : 0;
314 int inet_csk_listen_start(struct sock *sk, int backlog);
315 void inet_csk_listen_stop(struct sock *sk);
317 void inet_csk_addr2sockaddr(struct sock *sk, struct sockaddr *uaddr);
319 int inet_csk_compat_getsockopt(struct sock *sk, int level, int optname,
320 char __user *optval, int __user *optlen);
321 int inet_csk_compat_setsockopt(struct sock *sk, int level, int optname,
322 char __user *optval, unsigned int optlen);
324 struct dst_entry *inet_csk_update_pmtu(struct sock *sk, u32 mtu);
325 #endif /* _INET_CONNECTION_SOCK_H */