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 int (*conn_request)(struct sock *sk, struct sk_buff *skb);
43 struct sock *(*syn_recv_sock)(struct sock *sk, struct sk_buff *skb,
44 struct request_sock *req,
45 struct dst_entry *dst);
46 struct inet_peer *(*get_peer)(struct sock *sk, bool *release_it);
47 u16 net_header_len;
48 u16 sockaddr_len;
49 int (*setsockopt)(struct sock *sk, int level, int optname,
50 char __user *optval, unsigned int optlen);
51 int (*getsockopt)(struct sock *sk, int level, int optname,
52 char __user *optval, int __user *optlen);
53 #ifdef CONFIG_COMPAT
54 int (*compat_setsockopt)(struct sock *sk,
55 int level, int optname,
56 char __user *optval, unsigned int optlen);
57 int (*compat_getsockopt)(struct sock *sk,
58 int level, int optname,
59 char __user *optval, int __user *optlen);
60 #endif
61 void (*addr2sockaddr)(struct sock *sk, struct sockaddr *);
62 int (*bind_conflict)(const struct sock *sk,
63 const struct inet_bind_bucket *tb);
64 };
65
66 /** inet_connection_sock - INET connection oriented sock
67 *
68 * @icsk_accept_queue: FIFO of established children
69 * @icsk_bind_hash: Bind node
70 * @icsk_timeout: Timeout
71 * @icsk_retransmit_timer: Resend (no ack)
72 * @icsk_rto: Retransmit timeout
73 * @icsk_pmtu_cookie Last pmtu seen by socket
74 * @icsk_ca_ops Pluggable congestion control hook
75 * @icsk_af_ops Operations which are AF_INET{4,6} specific
76 * @icsk_ca_state: Congestion control state
77 * @icsk_retransmits: Number of unrecovered [RTO] timeouts
78 * @icsk_pending: Scheduled timer event
79 * @icsk_backoff: Backoff
80 * @icsk_syn_retries: Number of allowed SYN (or equivalent) retries
81 * @icsk_probes_out: unanswered 0 window probes
82 * @icsk_ext_hdr_len: Network protocol overhead (IP/IPv6 options)
83 * @icsk_ack: Delayed ACK control data
84 * @icsk_mtup; MTU probing control data
85 */
86 struct inet_connection_sock {
87 /* inet_sock has to be the first member! */
88 struct inet_sock icsk_inet;
89 struct request_sock_queue icsk_accept_queue;
90 struct inet_bind_bucket *icsk_bind_hash;
91 unsigned long icsk_timeout;
92 struct timer_list icsk_retransmit_timer;
93 struct timer_list icsk_delack_timer;
94 __u32 icsk_rto;
95 __u32 icsk_pmtu_cookie;
96 const struct tcp_congestion_ops *icsk_ca_ops;
97 const struct inet_connection_sock_af_ops *icsk_af_ops;
98 unsigned int (*icsk_sync_mss)(struct sock *sk, u32 pmtu);
99 __u8 icsk_ca_state;
100 __u8 icsk_retransmits;
101 __u8 icsk_pending;
102 __u8 icsk_backoff;
103 __u8 icsk_syn_retries;
104 __u8 icsk_probes_out;
105 __u16 icsk_ext_hdr_len;
106 struct {
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 */
116 } icsk_ack;
117 struct {
118 int enabled;
119
120 /* Range of MTUs to search */
121 int search_high;
122 int search_low;
123
124 /* Information on the current probe. */
125 int probe_size;
126 } icsk_mtup;
127 u32 icsk_ca_priv[16];
128 u32 icsk_user_timeout;
129 #define ICSK_CA_PRIV_SIZE (16 * sizeof(u32))
130 };
131
132 #define ICSK_TIME_RETRANS 1 /* Retransmit timer */
133 #define ICSK_TIME_DACK 2 /* Delayed ack timer */
134 #define ICSK_TIME_PROBE0 3 /* Zero window probe timer */
135
inet_csk(const struct sock * sk)136 static inline struct inet_connection_sock *inet_csk(const struct sock *sk)
137 {
138 return (struct inet_connection_sock *)sk;
139 }
140
inet_csk_ca(const struct sock * sk)141 static inline void *inet_csk_ca(const struct sock *sk)
142 {
143 return (void *)inet_csk(sk)->icsk_ca_priv;
144 }
145
146 extern struct sock *inet_csk_clone_lock(const struct sock *sk,
147 const struct request_sock *req,
148 const gfp_t priority);
149
150 enum inet_csk_ack_state_t {
151 ICSK_ACK_SCHED = 1,
152 ICSK_ACK_TIMER = 2,
153 ICSK_ACK_PUSHED = 4,
154 ICSK_ACK_PUSHED2 = 8
155 };
156
157 extern void inet_csk_init_xmit_timers(struct sock *sk,
158 void (*retransmit_handler)(unsigned long),
159 void (*delack_handler)(unsigned long),
160 void (*keepalive_handler)(unsigned long));
161 extern void inet_csk_clear_xmit_timers(struct sock *sk);
162
inet_csk_schedule_ack(struct sock * sk)163 static inline void inet_csk_schedule_ack(struct sock *sk)
164 {
165 inet_csk(sk)->icsk_ack.pending |= ICSK_ACK_SCHED;
166 }
167
inet_csk_ack_scheduled(const struct sock * sk)168 static inline int inet_csk_ack_scheduled(const struct sock *sk)
169 {
170 return inet_csk(sk)->icsk_ack.pending & ICSK_ACK_SCHED;
171 }
172
inet_csk_delack_init(struct sock * sk)173 static inline void inet_csk_delack_init(struct sock *sk)
174 {
175 memset(&inet_csk(sk)->icsk_ack, 0, sizeof(inet_csk(sk)->icsk_ack));
176 }
177
178 extern void inet_csk_delete_keepalive_timer(struct sock *sk);
179 extern void inet_csk_reset_keepalive_timer(struct sock *sk, unsigned long timeout);
180
181 #ifdef INET_CSK_DEBUG
182 extern const char inet_csk_timer_bug_msg[];
183 #endif
184
inet_csk_clear_xmit_timer(struct sock * sk,const int what)185 static inline void inet_csk_clear_xmit_timer(struct sock *sk, const int what)
186 {
187 struct inet_connection_sock *icsk = inet_csk(sk);
188
189 if (what == ICSK_TIME_RETRANS || what == ICSK_TIME_PROBE0) {
190 icsk->icsk_pending = 0;
191 #ifdef INET_CSK_CLEAR_TIMERS
192 sk_stop_timer(sk, &icsk->icsk_retransmit_timer);
193 #endif
194 } else if (what == ICSK_TIME_DACK) {
195 icsk->icsk_ack.blocked = icsk->icsk_ack.pending = 0;
196 #ifdef INET_CSK_CLEAR_TIMERS
197 sk_stop_timer(sk, &icsk->icsk_delack_timer);
198 #endif
199 }
200 #ifdef INET_CSK_DEBUG
201 else {
202 pr_debug("%s", inet_csk_timer_bug_msg);
203 }
204 #endif
205 }
206
207 /*
208 * Reset the retransmission timer
209 */
inet_csk_reset_xmit_timer(struct sock * sk,const int what,unsigned long when,const unsigned long max_when)210 static inline void inet_csk_reset_xmit_timer(struct sock *sk, const int what,
211 unsigned long when,
212 const unsigned long max_when)
213 {
214 struct inet_connection_sock *icsk = inet_csk(sk);
215
216 if (when > max_when) {
217 #ifdef INET_CSK_DEBUG
218 pr_debug("reset_xmit_timer: sk=%p %d when=0x%lx, caller=%p\n",
219 sk, what, when, current_text_addr());
220 #endif
221 when = max_when;
222 }
223
224 if (what == ICSK_TIME_RETRANS || what == ICSK_TIME_PROBE0) {
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);
232 }
233 #ifdef INET_CSK_DEBUG
234 else {
235 pr_debug("%s", inet_csk_timer_bug_msg);
236 }
237 #endif
238 }
239
240 extern struct sock *inet_csk_accept(struct sock *sk, int flags, int *err);
241
242 extern struct request_sock *inet_csk_search_req(const struct sock *sk,
243 struct request_sock ***prevp,
244 const __be16 rport,
245 const __be32 raddr,
246 const __be32 laddr);
247 extern int inet_csk_bind_conflict(const struct sock *sk,
248 const struct inet_bind_bucket *tb);
249 extern int inet_csk_get_port(struct sock *sk, unsigned short snum);
250
251 extern struct dst_entry* inet_csk_route_req(struct sock *sk,
252 struct flowi4 *fl4,
253 const struct request_sock *req);
254 extern struct dst_entry* inet_csk_route_child_sock(struct sock *sk,
255 struct sock *newsk,
256 const struct request_sock *req);
257
inet_csk_reqsk_queue_add(struct sock * sk,struct request_sock * req,struct sock * child)258 static inline void inet_csk_reqsk_queue_add(struct sock *sk,
259 struct request_sock *req,
260 struct sock *child)
261 {
262 reqsk_queue_add(&inet_csk(sk)->icsk_accept_queue, req, sk, child);
263 }
264
265 extern void inet_csk_reqsk_queue_hash_add(struct sock *sk,
266 struct request_sock *req,
267 unsigned long timeout);
268
inet_csk_reqsk_queue_removed(struct sock * sk,struct request_sock * req)269 static inline void inet_csk_reqsk_queue_removed(struct sock *sk,
270 struct request_sock *req)
271 {
272 if (reqsk_queue_removed(&inet_csk(sk)->icsk_accept_queue, req) == 0)
273 inet_csk_delete_keepalive_timer(sk);
274 }
275
inet_csk_reqsk_queue_added(struct sock * sk,const unsigned long timeout)276 static inline void inet_csk_reqsk_queue_added(struct sock *sk,
277 const unsigned long timeout)
278 {
279 if (reqsk_queue_added(&inet_csk(sk)->icsk_accept_queue) == 0)
280 inet_csk_reset_keepalive_timer(sk, timeout);
281 }
282
inet_csk_reqsk_queue_len(const struct sock * sk)283 static inline int inet_csk_reqsk_queue_len(const struct sock *sk)
284 {
285 return reqsk_queue_len(&inet_csk(sk)->icsk_accept_queue);
286 }
287
inet_csk_reqsk_queue_young(const struct sock * sk)288 static inline int inet_csk_reqsk_queue_young(const struct sock *sk)
289 {
290 return reqsk_queue_len_young(&inet_csk(sk)->icsk_accept_queue);
291 }
292
inet_csk_reqsk_queue_is_full(const struct sock * sk)293 static inline int inet_csk_reqsk_queue_is_full(const struct sock *sk)
294 {
295 return reqsk_queue_is_full(&inet_csk(sk)->icsk_accept_queue);
296 }
297
inet_csk_reqsk_queue_unlink(struct sock * sk,struct request_sock * req,struct request_sock ** prev)298 static inline void inet_csk_reqsk_queue_unlink(struct sock *sk,
299 struct request_sock *req,
300 struct request_sock **prev)
301 {
302 reqsk_queue_unlink(&inet_csk(sk)->icsk_accept_queue, req, prev);
303 }
304
inet_csk_reqsk_queue_drop(struct sock * sk,struct request_sock * req,struct request_sock ** prev)305 static inline void inet_csk_reqsk_queue_drop(struct sock *sk,
306 struct request_sock *req,
307 struct request_sock **prev)
308 {
309 inet_csk_reqsk_queue_unlink(sk, req, prev);
310 inet_csk_reqsk_queue_removed(sk, req);
311 reqsk_free(req);
312 }
313
314 extern void inet_csk_reqsk_queue_prune(struct sock *parent,
315 const unsigned long interval,
316 const unsigned long timeout,
317 const unsigned long max_rto);
318
319 extern void inet_csk_destroy_sock(struct sock *sk);
320 extern void inet_csk_prepare_forced_close(struct sock *sk);
321
322 /*
323 * LISTEN is a special case for poll..
324 */
inet_csk_listen_poll(const struct sock * sk)325 static inline unsigned int inet_csk_listen_poll(const struct sock *sk)
326 {
327 return !reqsk_queue_empty(&inet_csk(sk)->icsk_accept_queue) ?
328 (POLLIN | POLLRDNORM) : 0;
329 }
330
331 extern int inet_csk_listen_start(struct sock *sk, const int nr_table_entries);
332 extern void inet_csk_listen_stop(struct sock *sk);
333
334 extern void inet_csk_addr2sockaddr(struct sock *sk, struct sockaddr *uaddr);
335
336 extern int inet_csk_compat_getsockopt(struct sock *sk, int level, int optname,
337 char __user *optval, int __user *optlen);
338 extern int inet_csk_compat_setsockopt(struct sock *sk, int level, int optname,
339 char __user *optval, unsigned int optlen);
340 #endif /* _INET_CONNECTION_SOCK_H */
341