1 /*
2 * NET Generic infrastructure for INET connection oriented protocols.
3 *
4 * Definitions for inet_connection_sock
5 *
6 * Authors: Many people, see the TCP sources
7 *
8 * From code originally in TCP
9 *
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.
14 */
15 #ifndef _INET_CONNECTION_SOCK_H
16 #define _INET_CONNECTION_SOCK_H
17
18 #include <linux/compiler.h>
19 #include <linux/string.h>
20 #include <linux/timer.h>
21 #include <linux/poll.h>
22
23 #include <net/inet_sock.h>
24 #include <net/request_sock.h>
25
26 #define INET_CSK_DEBUG 1
27
28 /* Cancel timers, when they are not required. */
29 #undef INET_CSK_CLEAR_TIMERS
30
31 struct inet_bind_bucket;
32 struct tcp_congestion_ops;
33
34 /*
35 * Pointers to address related TCP functions
36 * (i.e. things that depend on the address family)
37 */
38 struct inet_connection_sock_af_ops {
39 int (*queue_xmit)(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);
47 u16 net_header_len;
48 u16 net_frag_header_len;
49 u16 sockaddr_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);
54 #ifdef CONFIG_COMPAT
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);
61 #endif
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 };
66
67 /** inet_connection_sock - INET connection oriented sock
68 *
69 * @icsk_accept_queue: FIFO of established children
70 * @icsk_bind_hash: Bind node
71 * @icsk_timeout: Timeout
72 * @icsk_retransmit_timer: Resend (no ack)
73 * @icsk_rto: Retransmit timeout
74 * @icsk_pmtu_cookie Last pmtu seen by socket
75 * @icsk_ca_ops Pluggable congestion control hook
76 * @icsk_af_ops Operations which are AF_INET{4,6} specific
77 * @icsk_ca_state: Congestion control state
78 * @icsk_retransmits: Number of unrecovered [RTO] timeouts
79 * @icsk_pending: Scheduled timer event
80 * @icsk_backoff: Backoff
81 * @icsk_syn_retries: Number of allowed SYN (or equivalent) retries
82 * @icsk_probes_out: unanswered 0 window probes
83 * @icsk_ext_hdr_len: Network protocol overhead (IP/IPv6 options)
84 * @icsk_ack: Delayed ACK control data
85 * @icsk_mtup; MTU probing control data
86 */
87 struct inet_connection_sock {
88 /* inet_sock has to be the first member! */
89 struct inet_sock icsk_inet;
90 struct request_sock_queue icsk_accept_queue;
91 struct inet_bind_bucket *icsk_bind_hash;
92 unsigned long icsk_timeout;
93 struct timer_list icsk_retransmit_timer;
94 struct timer_list icsk_delack_timer;
95 __u32 icsk_rto;
96 __u32 icsk_pmtu_cookie;
97 const struct tcp_congestion_ops *icsk_ca_ops;
98 const struct inet_connection_sock_af_ops *icsk_af_ops;
99 unsigned int (*icsk_sync_mss)(struct sock *sk, u32 pmtu);
100 __u8 icsk_ca_state;
101 __u8 icsk_retransmits;
102 __u8 icsk_pending;
103 __u8 icsk_backoff;
104 __u8 icsk_syn_retries;
105 __u8 icsk_probes_out;
106 __u16 icsk_ext_hdr_len;
107 struct {
108 __u8 pending; /* ACK is pending */
109 __u8 quick; /* Scheduled number of quick acks */
110 __u8 pingpong; /* The session is interactive */
111 __u8 blocked; /* Delayed ACK was blocked by socket lock */
112 __u32 ato; /* Predicted tick of soft clock */
113 unsigned long timeout; /* Currently scheduled timeout */
114 __u32 lrcvtime; /* timestamp of last received data packet */
115 __u16 last_seg_size; /* Size of last incoming segment */
116 __u16 rcv_mss; /* MSS used for delayed ACK decisions */
117 } icsk_ack;
118 struct {
119 int enabled;
120
121 /* Range of MTUs to search */
122 int search_high;
123 int search_low;
124
125 /* Information on the current probe. */
126 int probe_size;
127 } icsk_mtup;
128 u32 icsk_ca_priv[16];
129 u32 icsk_user_timeout;
130 #define ICSK_CA_PRIV_SIZE (16 * sizeof(u32))
131 };
132
133 #define ICSK_TIME_RETRANS 1 /* Retransmit timer */
134 #define ICSK_TIME_DACK 2 /* Delayed ack timer */
135 #define ICSK_TIME_PROBE0 3 /* Zero window probe timer */
136 #define ICSK_TIME_EARLY_RETRANS 4 /* Early retransmit timer */
137 #define ICSK_TIME_LOSS_PROBE 5 /* Tail loss probe timer */
138
inet_csk(const struct sock * sk)139 static inline struct inet_connection_sock *inet_csk(const struct sock *sk)
140 {
141 return (struct inet_connection_sock *)sk;
142 }
143
inet_csk_ca(const struct sock * sk)144 static inline void *inet_csk_ca(const struct sock *sk)
145 {
146 return (void *)inet_csk(sk)->icsk_ca_priv;
147 }
148
149 extern struct sock *inet_csk_clone_lock(const struct sock *sk,
150 const struct request_sock *req,
151 const gfp_t priority);
152
153 enum inet_csk_ack_state_t {
154 ICSK_ACK_SCHED = 1,
155 ICSK_ACK_TIMER = 2,
156 ICSK_ACK_PUSHED = 4,
157 ICSK_ACK_PUSHED2 = 8
158 };
159
160 extern void inet_csk_init_xmit_timers(struct sock *sk,
161 void (*retransmit_handler)(unsigned long),
162 void (*delack_handler)(unsigned long),
163 void (*keepalive_handler)(unsigned long));
164 extern void inet_csk_clear_xmit_timers(struct sock *sk);
165
inet_csk_schedule_ack(struct sock * sk)166 static inline void inet_csk_schedule_ack(struct sock *sk)
167 {
168 inet_csk(sk)->icsk_ack.pending |= ICSK_ACK_SCHED;
169 }
170
inet_csk_ack_scheduled(const struct sock * sk)171 static inline int inet_csk_ack_scheduled(const struct sock *sk)
172 {
173 return inet_csk(sk)->icsk_ack.pending & ICSK_ACK_SCHED;
174 }
175
inet_csk_delack_init(struct sock * sk)176 static inline void inet_csk_delack_init(struct sock *sk)
177 {
178 memset(&inet_csk(sk)->icsk_ack, 0, sizeof(inet_csk(sk)->icsk_ack));
179 }
180
181 extern void inet_csk_delete_keepalive_timer(struct sock *sk);
182 extern void inet_csk_reset_keepalive_timer(struct sock *sk, unsigned long timeout);
183
184 #ifdef INET_CSK_DEBUG
185 extern const char inet_csk_timer_bug_msg[];
186 #endif
187
inet_csk_clear_xmit_timer(struct sock * sk,const int what)188 static inline void inet_csk_clear_xmit_timer(struct sock *sk, const int what)
189 {
190 struct inet_connection_sock *icsk = inet_csk(sk);
191
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);
196 #endif
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);
201 #endif
202 }
203 #ifdef INET_CSK_DEBUG
204 else {
205 pr_debug("%s", inet_csk_timer_bug_msg);
206 }
207 #endif
208 }
209
210 /*
211 * Reset the retransmission timer
212 */
inet_csk_reset_xmit_timer(struct sock * sk,const int what,unsigned long when,const unsigned long max_when)213 static inline void inet_csk_reset_xmit_timer(struct sock *sk, const int what,
214 unsigned long when,
215 const unsigned long max_when)
216 {
217 struct inet_connection_sock *icsk = inet_csk(sk);
218
219 if (when > max_when) {
220 #ifdef INET_CSK_DEBUG
221 pr_debug("reset_xmit_timer: sk=%p %d when=0x%lx, caller=%p\n",
222 sk, what, when, current_text_addr());
223 #endif
224 when = max_when;
225 }
226
227 if (what == ICSK_TIME_RETRANS || what == ICSK_TIME_PROBE0 ||
228 what == ICSK_TIME_EARLY_RETRANS || what == ICSK_TIME_LOSS_PROBE) {
229 icsk->icsk_pending = what;
230 icsk->icsk_timeout = jiffies + when;
231 sk_reset_timer(sk, &icsk->icsk_retransmit_timer, icsk->icsk_timeout);
232 } else if (what == ICSK_TIME_DACK) {
233 icsk->icsk_ack.pending |= ICSK_ACK_TIMER;
234 icsk->icsk_ack.timeout = jiffies + when;
235 sk_reset_timer(sk, &icsk->icsk_delack_timer, icsk->icsk_ack.timeout);
236 }
237 #ifdef INET_CSK_DEBUG
238 else {
239 pr_debug("%s", inet_csk_timer_bug_msg);
240 }
241 #endif
242 }
243
244 extern struct sock *inet_csk_accept(struct sock *sk, int flags, int *err);
245
246 extern struct request_sock *inet_csk_search_req(const struct sock *sk,
247 struct request_sock ***prevp,
248 const __be16 rport,
249 const __be32 raddr,
250 const __be32 laddr);
251 extern int inet_csk_bind_conflict(const struct sock *sk,
252 const struct inet_bind_bucket *tb, bool relax);
253 extern int inet_csk_get_port(struct sock *sk, unsigned short snum);
254
255 extern struct dst_entry* inet_csk_route_req(struct sock *sk,
256 struct flowi4 *fl4,
257 const struct request_sock *req);
258 extern struct dst_entry* inet_csk_route_child_sock(struct sock *sk,
259 struct sock *newsk,
260 const struct request_sock *req);
261
inet_csk_reqsk_queue_add(struct sock * sk,struct request_sock * req,struct sock * child)262 static inline void inet_csk_reqsk_queue_add(struct sock *sk,
263 struct request_sock *req,
264 struct sock *child)
265 {
266 reqsk_queue_add(&inet_csk(sk)->icsk_accept_queue, req, sk, child);
267 }
268
269 extern void inet_csk_reqsk_queue_hash_add(struct sock *sk,
270 struct request_sock *req,
271 unsigned long timeout);
272
inet_csk_reqsk_queue_removed(struct sock * sk,struct request_sock * req)273 static inline void inet_csk_reqsk_queue_removed(struct sock *sk,
274 struct request_sock *req)
275 {
276 if (reqsk_queue_removed(&inet_csk(sk)->icsk_accept_queue, req) == 0)
277 inet_csk_delete_keepalive_timer(sk);
278 }
279
inet_csk_reqsk_queue_added(struct sock * sk,const unsigned long timeout)280 static inline void inet_csk_reqsk_queue_added(struct sock *sk,
281 const unsigned long timeout)
282 {
283 if (reqsk_queue_added(&inet_csk(sk)->icsk_accept_queue) == 0)
284 inet_csk_reset_keepalive_timer(sk, timeout);
285 }
286
inet_csk_reqsk_queue_len(const struct sock * sk)287 static inline int inet_csk_reqsk_queue_len(const struct sock *sk)
288 {
289 return reqsk_queue_len(&inet_csk(sk)->icsk_accept_queue);
290 }
291
inet_csk_reqsk_queue_young(const struct sock * sk)292 static inline int inet_csk_reqsk_queue_young(const struct sock *sk)
293 {
294 return reqsk_queue_len_young(&inet_csk(sk)->icsk_accept_queue);
295 }
296
inet_csk_reqsk_queue_is_full(const struct sock * sk)297 static inline int inet_csk_reqsk_queue_is_full(const struct sock *sk)
298 {
299 return reqsk_queue_is_full(&inet_csk(sk)->icsk_accept_queue);
300 }
301
inet_csk_reqsk_queue_unlink(struct sock * sk,struct request_sock * req,struct request_sock ** prev)302 static inline void inet_csk_reqsk_queue_unlink(struct sock *sk,
303 struct request_sock *req,
304 struct request_sock **prev)
305 {
306 reqsk_queue_unlink(&inet_csk(sk)->icsk_accept_queue, req, prev);
307 }
308
inet_csk_reqsk_queue_drop(struct sock * sk,struct request_sock * req,struct request_sock ** prev)309 static inline void inet_csk_reqsk_queue_drop(struct sock *sk,
310 struct request_sock *req,
311 struct request_sock **prev)
312 {
313 inet_csk_reqsk_queue_unlink(sk, req, prev);
314 inet_csk_reqsk_queue_removed(sk, req);
315 reqsk_free(req);
316 }
317
318 extern void inet_csk_reqsk_queue_prune(struct sock *parent,
319 const unsigned long interval,
320 const unsigned long timeout,
321 const unsigned long max_rto);
322
323 extern void inet_csk_destroy_sock(struct sock *sk);
324 extern void inet_csk_prepare_forced_close(struct sock *sk);
325
326 /*
327 * LISTEN is a special case for poll..
328 */
inet_csk_listen_poll(const struct sock * sk)329 static inline unsigned int inet_csk_listen_poll(const struct sock *sk)
330 {
331 return !reqsk_queue_empty(&inet_csk(sk)->icsk_accept_queue) ?
332 (POLLIN | POLLRDNORM) : 0;
333 }
334
335 extern int inet_csk_listen_start(struct sock *sk, const int nr_table_entries);
336 extern void inet_csk_listen_stop(struct sock *sk);
337
338 extern void inet_csk_addr2sockaddr(struct sock *sk, struct sockaddr *uaddr);
339
340 extern int inet_csk_compat_getsockopt(struct sock *sk, int level, int optname,
341 char __user *optval, int __user *optlen);
342 extern int inet_csk_compat_setsockopt(struct sock *sk, int level, int optname,
343 char __user *optval, unsigned int optlen);
344
345 extern struct dst_entry *inet_csk_update_pmtu(struct sock *sk, u32 mtu);
346 #endif /* _INET_CONNECTION_SOCK_H */
347