1 /* SPDX-License-Identifier: GPL-2.0-or-later */
3 * NET Generic infrastructure for INET connection oriented protocols.
5 * Definitions for inet_connection_sock
7 * Authors: Many people, see the TCP sources
9 * From code originally in TCP
11 #ifndef _INET_CONNECTION_SOCK_H
12 #define _INET_CONNECTION_SOCK_H
14 #include <linux/compiler.h>
15 #include <linux/string.h>
16 #include <linux/timer.h>
17 #include <linux/poll.h>
18 #include <linux/kernel.h>
19 #include <linux/sockptr.h>
21 #include <net/inet_sock.h>
22 #include <net/request_sock.h>
24 /* Cancel timers, when they are not required. */
25 #undef INET_CSK_CLEAR_TIMERS
27 struct inet_bind_bucket
;
28 struct tcp_congestion_ops
;
31 * Pointers to address related TCP functions
32 * (i.e. things that depend on the address family)
34 struct inet_connection_sock_af_ops
{
35 int (*queue_xmit
)(struct sock
*sk
, struct sk_buff
*skb
, struct flowi
*fl
);
36 void (*send_check
)(struct sock
*sk
, struct sk_buff
*skb
);
37 int (*rebuild_header
)(struct sock
*sk
);
38 void (*sk_rx_dst_set
)(struct sock
*sk
, const struct sk_buff
*skb
);
39 int (*conn_request
)(struct sock
*sk
, struct sk_buff
*skb
);
40 struct sock
*(*syn_recv_sock
)(const struct sock
*sk
, struct sk_buff
*skb
,
41 struct request_sock
*req
,
42 struct dst_entry
*dst
,
43 struct request_sock
*req_unhash
,
46 u16 net_frag_header_len
;
48 int (*setsockopt
)(struct sock
*sk
, int level
, int optname
,
49 sockptr_t optval
, unsigned int optlen
);
50 int (*getsockopt
)(struct sock
*sk
, int level
, int optname
,
51 char __user
*optval
, int __user
*optlen
);
52 void (*addr2sockaddr
)(struct sock
*sk
, struct sockaddr
*);
53 void (*mtu_reduced
)(struct sock
*sk
);
56 /** inet_connection_sock - INET connection oriented sock
58 * @icsk_accept_queue: FIFO of established children
59 * @icsk_bind_hash: Bind node
60 * @icsk_timeout: Timeout
61 * @icsk_retransmit_timer: Resend (no ack)
62 * @icsk_rto: Retransmit timeout
63 * @icsk_pmtu_cookie Last pmtu seen by socket
64 * @icsk_ca_ops Pluggable congestion control hook
65 * @icsk_af_ops Operations which are AF_INET{4,6} specific
66 * @icsk_ulp_ops Pluggable ULP control hook
67 * @icsk_ulp_data ULP private data
68 * @icsk_clean_acked Clean acked data hook
69 * @icsk_listen_portaddr_node hash to the portaddr listener hashtable
70 * @icsk_ca_state: Congestion control state
71 * @icsk_retransmits: Number of unrecovered [RTO] timeouts
72 * @icsk_pending: Scheduled timer event
73 * @icsk_backoff: Backoff
74 * @icsk_syn_retries: Number of allowed SYN (or equivalent) retries
75 * @icsk_probes_out: unanswered 0 window probes
76 * @icsk_ext_hdr_len: Network protocol overhead (IP/IPv6 options)
77 * @icsk_ack: Delayed ACK control data
78 * @icsk_mtup; MTU probing control data
80 struct inet_connection_sock
{
81 /* inet_sock has to be the first member! */
82 struct inet_sock icsk_inet
;
83 struct request_sock_queue icsk_accept_queue
;
84 struct inet_bind_bucket
*icsk_bind_hash
;
85 unsigned long icsk_timeout
;
86 struct timer_list icsk_retransmit_timer
;
87 struct timer_list icsk_delack_timer
;
89 __u32 icsk_pmtu_cookie
;
90 const struct tcp_congestion_ops
*icsk_ca_ops
;
91 const struct inet_connection_sock_af_ops
*icsk_af_ops
;
92 const struct tcp_ulp_ops
*icsk_ulp_ops
;
93 void __rcu
*icsk_ulp_data
;
94 void (*icsk_clean_acked
)(struct sock
*sk
, u32 acked_seq
);
95 struct hlist_node icsk_listen_portaddr_node
;
96 unsigned int (*icsk_sync_mss
)(struct sock
*sk
, u32 pmtu
);
100 __u8 icsk_retransmits
;
103 __u8 icsk_syn_retries
;
104 __u8 icsk_probes_out
;
105 __u16 icsk_ext_hdr_len
;
107 __u8 pending
; /* ACK is pending */
108 __u8 quick
; /* Scheduled number of quick acks */
109 __u8 pingpong
; /* The session is interactive */
110 __u8 blocked
; /* Delayed ACK was blocked by socket lock */
111 __u32 ato
; /* Predicted tick of soft clock */
112 unsigned long timeout
; /* Currently scheduled timeout */
113 __u32 lrcvtime
; /* timestamp of last received data packet */
114 __u16 last_seg_size
; /* Size of last incoming segment */
115 __u16 rcv_mss
; /* MSS used for delayed ACK decisions */
120 /* Range of MTUs to search */
124 /* Information on the current probe. */
129 u32 icsk_user_timeout
;
131 u64 icsk_ca_priv
[104 / sizeof(u64
)];
132 #define ICSK_CA_PRIV_SIZE (13 * sizeof(u64))
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 */
140 #define ICSK_TIME_REO_TIMEOUT 6 /* Reordering timer */
142 static inline struct inet_connection_sock
*inet_csk(const struct sock
*sk
)
144 return (struct inet_connection_sock
*)sk
;
147 static inline void *inet_csk_ca(const struct sock
*sk
)
149 return (void *)inet_csk(sk
)->icsk_ca_priv
;
152 struct sock
*inet_csk_clone_lock(const struct sock
*sk
,
153 const struct request_sock
*req
,
154 const gfp_t priority
);
156 enum inet_csk_ack_state_t
{
160 ICSK_ACK_PUSHED2
= 8,
161 ICSK_ACK_NOW
= 16 /* Send the next ACK immediately (once) */
164 void inet_csk_init_xmit_timers(struct sock
*sk
,
165 void (*retransmit_handler
)(struct timer_list
*),
166 void (*delack_handler
)(struct timer_list
*),
167 void (*keepalive_handler
)(struct timer_list
*));
168 void inet_csk_clear_xmit_timers(struct sock
*sk
);
170 static inline void inet_csk_schedule_ack(struct sock
*sk
)
172 inet_csk(sk
)->icsk_ack
.pending
|= ICSK_ACK_SCHED
;
175 static inline int inet_csk_ack_scheduled(const struct sock
*sk
)
177 return inet_csk(sk
)->icsk_ack
.pending
& ICSK_ACK_SCHED
;
180 static inline void inet_csk_delack_init(struct sock
*sk
)
182 memset(&inet_csk(sk
)->icsk_ack
, 0, sizeof(inet_csk(sk
)->icsk_ack
));
185 void inet_csk_delete_keepalive_timer(struct sock
*sk
);
186 void inet_csk_reset_keepalive_timer(struct sock
*sk
, unsigned long timeout
);
188 static inline void inet_csk_clear_xmit_timer(struct sock
*sk
, const int what
)
190 struct inet_connection_sock
*icsk
= inet_csk(sk
);
192 if (what
== ICSK_TIME_RETRANS
|| what
== ICSK_TIME_PROBE0
) {
193 icsk
->icsk_pending
= 0;
194 #ifdef INET_CSK_CLEAR_TIMERS
195 sk_stop_timer(sk
, &icsk
->icsk_retransmit_timer
);
197 } else if (what
== ICSK_TIME_DACK
) {
198 icsk
->icsk_ack
.blocked
= icsk
->icsk_ack
.pending
= 0;
199 #ifdef INET_CSK_CLEAR_TIMERS
200 sk_stop_timer(sk
, &icsk
->icsk_delack_timer
);
203 pr_debug("inet_csk BUG: unknown timer value\n");
208 * Reset the retransmission timer
210 static inline void inet_csk_reset_xmit_timer(struct sock
*sk
, const int what
,
212 const unsigned long max_when
)
214 struct inet_connection_sock
*icsk
= inet_csk(sk
);
216 if (when
> max_when
) {
217 pr_debug("reset_xmit_timer: sk=%p %d when=0x%lx, caller=%p\n",
218 sk
, what
, when
, (void *)_THIS_IP_
);
222 if (what
== ICSK_TIME_RETRANS
|| what
== ICSK_TIME_PROBE0
||
223 what
== ICSK_TIME_EARLY_RETRANS
|| what
== ICSK_TIME_LOSS_PROBE
||
224 what
== ICSK_TIME_REO_TIMEOUT
) {
225 icsk
->icsk_pending
= what
;
226 icsk
->icsk_timeout
= jiffies
+ when
;
227 sk_reset_timer(sk
, &icsk
->icsk_retransmit_timer
, icsk
->icsk_timeout
);
228 } else if (what
== ICSK_TIME_DACK
) {
229 icsk
->icsk_ack
.pending
|= ICSK_ACK_TIMER
;
230 icsk
->icsk_ack
.timeout
= jiffies
+ when
;
231 sk_reset_timer(sk
, &icsk
->icsk_delack_timer
, icsk
->icsk_ack
.timeout
);
233 pr_debug("inet_csk BUG: unknown timer value\n");
237 static inline unsigned long
238 inet_csk_rto_backoff(const struct inet_connection_sock
*icsk
,
239 unsigned long max_when
)
241 u64 when
= (u64
)icsk
->icsk_rto
<< icsk
->icsk_backoff
;
243 return (unsigned long)min_t(u64
, when
, max_when
);
246 struct sock
*inet_csk_accept(struct sock
*sk
, int flags
, int *err
, bool kern
);
248 int inet_csk_get_port(struct sock
*sk
, unsigned short snum
);
250 struct dst_entry
*inet_csk_route_req(const struct sock
*sk
, struct flowi4
*fl4
,
251 const struct request_sock
*req
);
252 struct dst_entry
*inet_csk_route_child_sock(const struct sock
*sk
,
254 const struct request_sock
*req
);
256 struct sock
*inet_csk_reqsk_queue_add(struct sock
*sk
,
257 struct request_sock
*req
,
259 void inet_csk_reqsk_queue_hash_add(struct sock
*sk
, struct request_sock
*req
,
260 unsigned long timeout
);
261 struct sock
*inet_csk_complete_hashdance(struct sock
*sk
, struct sock
*child
,
262 struct request_sock
*req
,
265 static inline void inet_csk_reqsk_queue_added(struct sock
*sk
)
267 reqsk_queue_added(&inet_csk(sk
)->icsk_accept_queue
);
270 static inline int inet_csk_reqsk_queue_len(const struct sock
*sk
)
272 return reqsk_queue_len(&inet_csk(sk
)->icsk_accept_queue
);
275 static inline int inet_csk_reqsk_queue_is_full(const struct sock
*sk
)
277 return inet_csk_reqsk_queue_len(sk
) >= sk
->sk_max_ack_backlog
;
280 void inet_csk_reqsk_queue_drop(struct sock
*sk
, struct request_sock
*req
);
281 void inet_csk_reqsk_queue_drop_and_put(struct sock
*sk
, struct request_sock
*req
);
283 static inline void inet_csk_prepare_for_destroy_sock(struct sock
*sk
)
285 /* The below has to be done to allow calling inet_csk_destroy_sock */
286 sock_set_flag(sk
, SOCK_DEAD
);
287 percpu_counter_inc(sk
->sk_prot
->orphan_count
);
290 void inet_csk_destroy_sock(struct sock
*sk
);
291 void inet_csk_prepare_forced_close(struct sock
*sk
);
294 * LISTEN is a special case for poll..
296 static inline __poll_t
inet_csk_listen_poll(const struct sock
*sk
)
298 return !reqsk_queue_empty(&inet_csk(sk
)->icsk_accept_queue
) ?
299 (EPOLLIN
| EPOLLRDNORM
) : 0;
302 int inet_csk_listen_start(struct sock
*sk
, int backlog
);
303 void inet_csk_listen_stop(struct sock
*sk
);
305 void inet_csk_addr2sockaddr(struct sock
*sk
, struct sockaddr
*uaddr
);
307 struct dst_entry
*inet_csk_update_pmtu(struct sock
*sk
, u32 mtu
);
309 #define TCP_PINGPONG_THRESH 3
311 static inline void inet_csk_enter_pingpong_mode(struct sock
*sk
)
313 inet_csk(sk
)->icsk_ack
.pingpong
= TCP_PINGPONG_THRESH
;
316 static inline void inet_csk_exit_pingpong_mode(struct sock
*sk
)
318 inet_csk(sk
)->icsk_ack
.pingpong
= 0;
321 static inline bool inet_csk_in_pingpong_mode(struct sock
*sk
)
323 return inet_csk(sk
)->icsk_ack
.pingpong
>= TCP_PINGPONG_THRESH
;
326 static inline void inet_csk_inc_pingpong_cnt(struct sock
*sk
)
328 struct inet_connection_sock
*icsk
= inet_csk(sk
);
330 if (icsk
->icsk_ack
.pingpong
< U8_MAX
)
331 icsk
->icsk_ack
.pingpong
++;
334 static inline bool inet_csk_has_ulp(struct sock
*sk
)
336 return inet_sk(sk
)->is_icsk
&& !!inet_csk(sk
)->icsk_ulp_ops
;
339 #endif /* _INET_CONNECTION_SOCK_H */