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)(struct sock *sk, struct sk_buff *skb,
45 struct request_sock *req,
46 struct dst_entry *dst);
48 u16 net_frag_header_len;
50 int (*setsockopt)(struct sock *sk, int level, int optname,
51 char __user *optval, unsigned int optlen);
52 int (*getsockopt)(struct sock *sk, int level, int optname,
53 char __user *optval, int __user *optlen);
55 int (*compat_setsockopt)(struct sock *sk,
56 int level, int optname,
57 char __user *optval, unsigned int optlen);
58 int (*compat_getsockopt)(struct sock *sk,
59 int level, int optname,
60 char __user *optval, int __user *optlen);
62 void (*addr2sockaddr)(struct sock *sk, struct sockaddr *);
63 int (*bind_conflict)(const struct sock *sk,
64 const struct inet_bind_bucket *tb, bool relax);
65 void (*mtu_reduced)(struct sock *sk);
68 /** inet_connection_sock - INET connection oriented sock
70 * @icsk_accept_queue: FIFO of established children
71 * @icsk_bind_hash: Bind node
72 * @icsk_timeout: Timeout
73 * @icsk_retransmit_timer: Resend (no ack)
74 * @icsk_rto: Retransmit timeout
75 * @icsk_pmtu_cookie Last pmtu seen by socket
76 * @icsk_ca_ops Pluggable congestion control hook
77 * @icsk_af_ops Operations which are AF_INET{4,6} specific
78 * @icsk_ca_state: Congestion control state
79 * @icsk_retransmits: Number of unrecovered [RTO] timeouts
80 * @icsk_pending: Scheduled timer event
81 * @icsk_backoff: Backoff
82 * @icsk_syn_retries: Number of allowed SYN (or equivalent) retries
83 * @icsk_probes_out: unanswered 0 window probes
84 * @icsk_ext_hdr_len: Network protocol overhead (IP/IPv6 options)
85 * @icsk_ack: Delayed ACK control data
86 * @icsk_mtup; MTU probing control data
88 struct inet_connection_sock {
89 /* inet_sock has to be the first member! */
90 struct inet_sock icsk_inet;
91 struct request_sock_queue icsk_accept_queue;
92 struct inet_bind_bucket *icsk_bind_hash;
93 unsigned long icsk_timeout;
94 struct timer_list icsk_retransmit_timer;
95 struct timer_list icsk_delack_timer;
97 __u32 icsk_pmtu_cookie;
98 const struct tcp_congestion_ops *icsk_ca_ops;
99 const struct inet_connection_sock_af_ops *icsk_af_ops;
100 unsigned int (*icsk_sync_mss)(struct sock *sk, u32 pmtu);
101 __u8 icsk_ca_state:7,
102 icsk_ca_dst_locked:1;
103 __u8 icsk_retransmits;
106 __u8 icsk_syn_retries;
107 __u8 icsk_probes_out;
108 __u16 icsk_ext_hdr_len;
110 __u8 pending; /* ACK is pending */
111 __u8 quick; /* Scheduled number of quick acks */
112 __u8 pingpong; /* The session is interactive */
113 __u8 blocked; /* Delayed ACK was blocked by socket lock */
114 __u32 ato; /* Predicted tick of soft clock */
115 unsigned long timeout; /* Currently scheduled timeout */
116 __u32 lrcvtime; /* timestamp of last received data packet */
117 __u16 last_seg_size; /* Size of last incoming segment */
118 __u16 rcv_mss; /* MSS used for delayed ACK decisions */
123 /* Range of MTUs to search */
127 /* Information on the current probe. */
130 u32 icsk_ca_priv[16];
131 u32 icsk_user_timeout;
132 #define ICSK_CA_PRIV_SIZE (16 * sizeof(u32))
135 #define ICSK_TIME_RETRANS 1 /* Retransmit timer */
136 #define ICSK_TIME_DACK 2 /* Delayed ack timer */
137 #define ICSK_TIME_PROBE0 3 /* Zero window probe timer */
138 #define ICSK_TIME_EARLY_RETRANS 4 /* Early retransmit timer */
139 #define ICSK_TIME_LOSS_PROBE 5 /* Tail loss probe timer */
141 static inline struct inet_connection_sock *inet_csk(const struct sock *sk)
143 return (struct inet_connection_sock *)sk;
146 static inline void *inet_csk_ca(const struct sock *sk)
148 return (void *)inet_csk(sk)->icsk_ca_priv;
151 struct sock *inet_csk_clone_lock(const struct sock *sk,
152 const struct request_sock *req,
153 const gfp_t priority);
155 enum inet_csk_ack_state_t {
162 void inet_csk_init_xmit_timers(struct sock *sk,
163 void (*retransmit_handler)(unsigned long),
164 void (*delack_handler)(unsigned long),
165 void (*keepalive_handler)(unsigned long));
166 void inet_csk_clear_xmit_timers(struct sock *sk);
168 static inline void inet_csk_schedule_ack(struct sock *sk)
170 inet_csk(sk)->icsk_ack.pending |= ICSK_ACK_SCHED;
173 static inline int inet_csk_ack_scheduled(const struct sock *sk)
175 return inet_csk(sk)->icsk_ack.pending & ICSK_ACK_SCHED;
178 static inline void inet_csk_delack_init(struct sock *sk)
180 memset(&inet_csk(sk)->icsk_ack, 0, sizeof(inet_csk(sk)->icsk_ack));
183 void inet_csk_delete_keepalive_timer(struct sock *sk);
184 void inet_csk_reset_keepalive_timer(struct sock *sk, unsigned long timeout);
186 #ifdef INET_CSK_DEBUG
187 extern const char inet_csk_timer_bug_msg[];
190 static inline void inet_csk_clear_xmit_timer(struct sock *sk, const int what)
192 struct inet_connection_sock *icsk = inet_csk(sk);
194 if (what == ICSK_TIME_RETRANS || what == ICSK_TIME_PROBE0) {
195 icsk->icsk_pending = 0;
196 #ifdef INET_CSK_CLEAR_TIMERS
197 sk_stop_timer(sk, &icsk->icsk_retransmit_timer);
199 } else if (what == ICSK_TIME_DACK) {
200 icsk->icsk_ack.blocked = icsk->icsk_ack.pending = 0;
201 #ifdef INET_CSK_CLEAR_TIMERS
202 sk_stop_timer(sk, &icsk->icsk_delack_timer);
205 #ifdef INET_CSK_DEBUG
207 pr_debug("%s", inet_csk_timer_bug_msg);
213 * Reset the retransmission timer
215 static inline void inet_csk_reset_xmit_timer(struct sock *sk, const int what,
217 const unsigned long max_when)
219 struct inet_connection_sock *icsk = inet_csk(sk);
221 if (when > max_when) {
222 #ifdef INET_CSK_DEBUG
223 pr_debug("reset_xmit_timer: sk=%p %d when=0x%lx, caller=%p\n",
224 sk, what, when, current_text_addr());
229 if (what == ICSK_TIME_RETRANS || what == ICSK_TIME_PROBE0 ||
230 what == ICSK_TIME_EARLY_RETRANS || what == ICSK_TIME_LOSS_PROBE) {
231 icsk->icsk_pending = what;
232 icsk->icsk_timeout = jiffies + when;
233 sk_reset_timer(sk, &icsk->icsk_retransmit_timer, icsk->icsk_timeout);
234 } else if (what == ICSK_TIME_DACK) {
235 icsk->icsk_ack.pending |= ICSK_ACK_TIMER;
236 icsk->icsk_ack.timeout = jiffies + when;
237 sk_reset_timer(sk, &icsk->icsk_delack_timer, icsk->icsk_ack.timeout);
239 #ifdef INET_CSK_DEBUG
241 pr_debug("%s", inet_csk_timer_bug_msg);
246 static inline unsigned long
247 inet_csk_rto_backoff(const struct inet_connection_sock *icsk,
248 unsigned long max_when)
250 u64 when = (u64)icsk->icsk_rto << icsk->icsk_backoff;
252 return (unsigned long)min_t(u64, when, max_when);
255 struct sock *inet_csk_accept(struct sock *sk, int flags, int *err);
257 struct request_sock *inet_csk_search_req(const struct sock *sk,
258 struct request_sock ***prevp,
262 int inet_csk_bind_conflict(const struct sock *sk,
263 const struct inet_bind_bucket *tb, bool relax);
264 int inet_csk_get_port(struct sock *sk, unsigned short snum);
266 struct dst_entry *inet_csk_route_req(struct sock *sk, struct flowi4 *fl4,
267 const struct request_sock *req);
268 struct dst_entry *inet_csk_route_child_sock(struct sock *sk, struct sock *newsk,
269 const struct request_sock *req);
271 static inline void inet_csk_reqsk_queue_add(struct sock *sk,
272 struct request_sock *req,
275 reqsk_queue_add(&inet_csk(sk)->icsk_accept_queue, req, sk, child);
278 void inet_csk_reqsk_queue_hash_add(struct sock *sk, struct request_sock *req,
279 unsigned long timeout);
281 static inline void inet_csk_reqsk_queue_removed(struct sock *sk,
282 struct request_sock *req)
284 if (reqsk_queue_removed(&inet_csk(sk)->icsk_accept_queue, req) == 0)
285 inet_csk_delete_keepalive_timer(sk);
288 static inline void inet_csk_reqsk_queue_added(struct sock *sk,
289 const unsigned long timeout)
291 if (reqsk_queue_added(&inet_csk(sk)->icsk_accept_queue) == 0)
292 inet_csk_reset_keepalive_timer(sk, timeout);
295 static inline int inet_csk_reqsk_queue_len(const struct sock *sk)
297 return reqsk_queue_len(&inet_csk(sk)->icsk_accept_queue);
300 static inline int inet_csk_reqsk_queue_young(const struct sock *sk)
302 return reqsk_queue_len_young(&inet_csk(sk)->icsk_accept_queue);
305 static inline int inet_csk_reqsk_queue_is_full(const struct sock *sk)
307 return reqsk_queue_is_full(&inet_csk(sk)->icsk_accept_queue);
310 static inline void inet_csk_reqsk_queue_unlink(struct sock *sk,
311 struct request_sock *req,
312 struct request_sock **prev)
314 reqsk_queue_unlink(&inet_csk(sk)->icsk_accept_queue, req, prev);
317 static inline void inet_csk_reqsk_queue_drop(struct sock *sk,
318 struct request_sock *req,
319 struct request_sock **prev)
321 inet_csk_reqsk_queue_unlink(sk, req, prev);
322 inet_csk_reqsk_queue_removed(sk, req);
326 void inet_csk_reqsk_queue_prune(struct sock *parent,
327 const unsigned long interval,
328 const unsigned long timeout,
329 const unsigned long max_rto);
331 void inet_csk_destroy_sock(struct sock *sk);
332 void inet_csk_prepare_forced_close(struct sock *sk);
335 * LISTEN is a special case for poll..
337 static inline unsigned int inet_csk_listen_poll(const struct sock *sk)
339 return !reqsk_queue_empty(&inet_csk(sk)->icsk_accept_queue) ?
340 (POLLIN | POLLRDNORM) : 0;
343 int inet_csk_listen_start(struct sock *sk, const int nr_table_entries);
344 void inet_csk_listen_stop(struct sock *sk);
346 void inet_csk_addr2sockaddr(struct sock *sk, struct sockaddr *uaddr);
348 int inet_csk_compat_getsockopt(struct sock *sk, int level, int optname,
349 char __user *optval, int __user *optlen);
350 int inet_csk_compat_setsockopt(struct sock *sk, int level, int optname,
351 char __user *optval, unsigned int optlen);
353 struct dst_entry *inet_csk_update_pmtu(struct sock *sk, u32 mtu);
354 #endif /* _INET_CONNECTION_SOCK_H */