4e5a9ff99fc3d08af5519369c9ab887b59fdb06c
[pandora-kernel.git] / include / net / inet_connection_sock.h
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
22 #include <net/inet_sock.h>
23 #include <net/request_sock.h>
24
25 #define INET_CSK_DEBUG 1
26
27 /* Cancel timers, when they are not required. */
28 #undef INET_CSK_CLEAR_TIMERS
29
30 struct inet_bind_bucket;
31 struct inet_hashinfo;
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, int ipfragok);
40         void        (*send_check)(struct sock *sk, int len,
41                                   struct sk_buff *skb);
42         int         (*rebuild_header)(struct sock *sk);
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         int         (*remember_stamp)(struct sock *sk);
48         __u16       net_header_len;
49         int         (*setsockopt)(struct sock *sk, int level, int optname, 
50                                   char __user *optval, int optlen);
51         int         (*getsockopt)(struct sock *sk, int level, int optname, 
52                                   char __user *optval, int __user *optlen);
53         void        (*addr2sockaddr)(struct sock *sk, struct sockaddr *);
54         int sockaddr_len;
55 };
56
57 /** inet_connection_sock - INET connection oriented sock
58  *
59  * @icsk_accept_queue:     FIFO of established children 
60  * @icsk_bind_hash:        Bind node
61  * @icsk_timeout:          Timeout
62  * @icsk_retransmit_timer: Resend (no ack)
63  * @icsk_rto:              Retransmit timeout
64  * @icsk_pmtu_cookie       Last pmtu seen by socket
65  * @icsk_ca_ops            Pluggable congestion control hook
66  * @icsk_af_ops            Operations which are AF_INET{4,6} specific
67  * @icsk_ca_state:         Congestion control state
68  * @icsk_retransmits:      Number of unrecovered [RTO] timeouts
69  * @icsk_pending:          Scheduled timer event
70  * @icsk_backoff:          Backoff
71  * @icsk_syn_retries:      Number of allowed SYN (or equivalent) retries
72  * @icsk_probes_out:       unanswered 0 window probes
73  * @icsk_ext_hdr_len:      Network protocol overhead (IP/IPv6 options)
74  * @icsk_ack:              Delayed ACK control data
75  * @icsk_mtup;             MTU probing control data
76  */
77 struct inet_connection_sock {
78         /* inet_sock has to be the first member! */
79         struct inet_sock          icsk_inet;
80         struct request_sock_queue icsk_accept_queue;
81         struct inet_bind_bucket   *icsk_bind_hash;
82         unsigned long             icsk_timeout;
83         struct timer_list         icsk_retransmit_timer;
84         struct timer_list         icsk_delack_timer;
85         __u32                     icsk_rto;
86         __u32                     icsk_pmtu_cookie;
87         const struct tcp_congestion_ops *icsk_ca_ops;
88         const struct inet_connection_sock_af_ops *icsk_af_ops;
89         unsigned int              (*icsk_sync_mss)(struct sock *sk, u32 pmtu);
90         __u8                      icsk_ca_state;
91         __u8                      icsk_retransmits;
92         __u8                      icsk_pending;
93         __u8                      icsk_backoff;
94         __u8                      icsk_syn_retries;
95         __u8                      icsk_probes_out;
96         __u16                     icsk_ext_hdr_len;
97         struct {
98                 __u8              pending;       /* ACK is pending                         */
99                 __u8              quick;         /* Scheduled number of quick acks         */
100                 __u8              pingpong;      /* The session is interactive             */
101                 __u8              blocked;       /* Delayed ACK was blocked by socket lock */
102                 __u32             ato;           /* Predicted tick of soft clock           */
103                 unsigned long     timeout;       /* Currently scheduled timeout            */
104                 __u32             lrcvtime;      /* timestamp of last received data packet */
105                 __u16             last_seg_size; /* Size of last incoming segment          */
106                 __u16             rcv_mss;       /* MSS used for delayed ACK decisions     */ 
107         } icsk_ack;
108         struct {
109                 int               enabled;
110
111                 /* Range of MTUs to search */
112                 int               search_high;
113                 int               search_low;
114
115                 /* Information on the current probe. */
116                 int               probe_size;
117         } icsk_mtup;
118         u32                       icsk_ca_priv[16];
119 #define ICSK_CA_PRIV_SIZE       (16 * sizeof(u32))
120 };
121
122 #define ICSK_TIME_RETRANS       1       /* Retransmit timer */
123 #define ICSK_TIME_DACK          2       /* Delayed ack timer */
124 #define ICSK_TIME_PROBE0        3       /* Zero window probe timer */
125 #define ICSK_TIME_KEEPOPEN      4       /* Keepalive timer */
126
127 static inline struct inet_connection_sock *inet_csk(const struct sock *sk)
128 {
129         return (struct inet_connection_sock *)sk;
130 }
131
132 static inline void *inet_csk_ca(const struct sock *sk)
133 {
134         return (void *)inet_csk(sk)->icsk_ca_priv;
135 }
136
137 extern struct sock *inet_csk_clone(struct sock *sk,
138                                    const struct request_sock *req,
139                                    const gfp_t priority);
140
141 enum inet_csk_ack_state_t {
142         ICSK_ACK_SCHED  = 1,
143         ICSK_ACK_TIMER  = 2,
144         ICSK_ACK_PUSHED = 4
145 };
146
147 extern void inet_csk_init_xmit_timers(struct sock *sk,
148                                       void (*retransmit_handler)(unsigned long),
149                                       void (*delack_handler)(unsigned long),
150                                       void (*keepalive_handler)(unsigned long));
151 extern void inet_csk_clear_xmit_timers(struct sock *sk);
152
153 static inline void inet_csk_schedule_ack(struct sock *sk)
154 {
155         inet_csk(sk)->icsk_ack.pending |= ICSK_ACK_SCHED;
156 }
157
158 static inline int inet_csk_ack_scheduled(const struct sock *sk)
159 {
160         return inet_csk(sk)->icsk_ack.pending & ICSK_ACK_SCHED;
161 }
162
163 static inline void inet_csk_delack_init(struct sock *sk)
164 {
165         memset(&inet_csk(sk)->icsk_ack, 0, sizeof(inet_csk(sk)->icsk_ack));
166 }
167
168 extern void inet_csk_delete_keepalive_timer(struct sock *sk);
169 extern void inet_csk_reset_keepalive_timer(struct sock *sk, unsigned long timeout);
170
171 #ifdef INET_CSK_DEBUG
172 extern const char inet_csk_timer_bug_msg[];
173 #endif
174
175 static inline void inet_csk_clear_xmit_timer(struct sock *sk, const int what)
176 {
177         struct inet_connection_sock *icsk = inet_csk(sk);
178         
179         if (what == ICSK_TIME_RETRANS || what == ICSK_TIME_PROBE0) {
180                 icsk->icsk_pending = 0;
181 #ifdef INET_CSK_CLEAR_TIMERS
182                 sk_stop_timer(sk, &icsk->icsk_retransmit_timer);
183 #endif
184         } else if (what == ICSK_TIME_DACK) {
185                 icsk->icsk_ack.blocked = icsk->icsk_ack.pending = 0;
186 #ifdef INET_CSK_CLEAR_TIMERS
187                 sk_stop_timer(sk, &icsk->icsk_delack_timer);
188 #endif
189         }
190 #ifdef INET_CSK_DEBUG
191         else {
192                 pr_debug("%s", inet_csk_timer_bug_msg);
193         }
194 #endif
195 }
196
197 /*
198  *      Reset the retransmission timer
199  */
200 static inline void inet_csk_reset_xmit_timer(struct sock *sk, const int what,
201                                              unsigned long when,
202                                              const unsigned long max_when)
203 {
204         struct inet_connection_sock *icsk = inet_csk(sk);
205
206         if (when > max_when) {
207 #ifdef INET_CSK_DEBUG
208                 pr_debug("reset_xmit_timer: sk=%p %d when=0x%lx, caller=%p\n",
209                          sk, what, when, current_text_addr());
210 #endif
211                 when = max_when;
212         }
213
214         if (what == ICSK_TIME_RETRANS || what == ICSK_TIME_PROBE0) {
215                 icsk->icsk_pending = what;
216                 icsk->icsk_timeout = jiffies + when;
217                 sk_reset_timer(sk, &icsk->icsk_retransmit_timer, icsk->icsk_timeout);
218         } else if (what == ICSK_TIME_DACK) {
219                 icsk->icsk_ack.pending |= ICSK_ACK_TIMER;
220                 icsk->icsk_ack.timeout = jiffies + when;
221                 sk_reset_timer(sk, &icsk->icsk_delack_timer, icsk->icsk_ack.timeout);
222         }
223 #ifdef INET_CSK_DEBUG
224         else {
225                 pr_debug("%s", inet_csk_timer_bug_msg);
226         }
227 #endif
228 }
229
230 extern struct sock *inet_csk_accept(struct sock *sk, int flags, int *err);
231
232 extern struct request_sock *inet_csk_search_req(const struct sock *sk,
233                                                 struct request_sock ***prevp,
234                                                 const __u16 rport,
235                                                 const __u32 raddr,
236                                                 const __u32 laddr);
237 extern int inet_csk_bind_conflict(const struct sock *sk,
238                                   const struct inet_bind_bucket *tb);
239 extern int inet_csk_get_port(struct inet_hashinfo *hashinfo,
240                              struct sock *sk, unsigned short snum,
241                              int (*bind_conflict)(const struct sock *sk,
242                                                   const struct inet_bind_bucket *tb));
243
244 extern struct dst_entry* inet_csk_route_req(struct sock *sk,
245                                             const struct request_sock *req);
246
247 static inline void inet_csk_reqsk_queue_add(struct sock *sk,
248                                             struct request_sock *req,
249                                             struct sock *child)
250 {
251         reqsk_queue_add(&inet_csk(sk)->icsk_accept_queue, req, sk, child);
252 }
253
254 extern void inet_csk_reqsk_queue_hash_add(struct sock *sk,
255                                           struct request_sock *req,
256                                           unsigned long timeout);
257
258 static inline void inet_csk_reqsk_queue_removed(struct sock *sk,
259                                                 struct request_sock *req)
260 {
261         if (reqsk_queue_removed(&inet_csk(sk)->icsk_accept_queue, req) == 0)
262                 inet_csk_delete_keepalive_timer(sk);
263 }
264
265 static inline void inet_csk_reqsk_queue_added(struct sock *sk,
266                                               const unsigned long timeout)
267 {
268         if (reqsk_queue_added(&inet_csk(sk)->icsk_accept_queue) == 0)
269                 inet_csk_reset_keepalive_timer(sk, timeout);
270 }
271
272 static inline int inet_csk_reqsk_queue_len(const struct sock *sk)
273 {
274         return reqsk_queue_len(&inet_csk(sk)->icsk_accept_queue);
275 }
276
277 static inline int inet_csk_reqsk_queue_young(const struct sock *sk)
278 {
279         return reqsk_queue_len_young(&inet_csk(sk)->icsk_accept_queue);
280 }
281
282 static inline int inet_csk_reqsk_queue_is_full(const struct sock *sk)
283 {
284         return reqsk_queue_is_full(&inet_csk(sk)->icsk_accept_queue);
285 }
286
287 static inline void inet_csk_reqsk_queue_unlink(struct sock *sk,
288                                                struct request_sock *req,
289                                                struct request_sock **prev)
290 {
291         reqsk_queue_unlink(&inet_csk(sk)->icsk_accept_queue, req, prev);
292 }
293
294 static inline void inet_csk_reqsk_queue_drop(struct sock *sk,
295                                              struct request_sock *req,
296                                              struct request_sock **prev)
297 {
298         inet_csk_reqsk_queue_unlink(sk, req, prev);
299         inet_csk_reqsk_queue_removed(sk, req);
300         reqsk_free(req);
301 }
302
303 extern void inet_csk_reqsk_queue_prune(struct sock *parent,
304                                        const unsigned long interval,
305                                        const unsigned long timeout,
306                                        const unsigned long max_rto);
307
308 extern void inet_csk_destroy_sock(struct sock *sk);
309
310 /*
311  * LISTEN is a special case for poll..
312  */
313 static inline unsigned int inet_csk_listen_poll(const struct sock *sk)
314 {
315         return !reqsk_queue_empty(&inet_csk(sk)->icsk_accept_queue) ?
316                         (POLLIN | POLLRDNORM) : 0;
317 }
318
319 extern int  inet_csk_listen_start(struct sock *sk, const int nr_table_entries);
320 extern void inet_csk_listen_stop(struct sock *sk);
321
322 extern void inet_csk_addr2sockaddr(struct sock *sk, struct sockaddr *uaddr);
323
324 #endif /* _INET_CONNECTION_SOCK_H */