Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc
[linux-2.6] / net / ipv4 / ipvs / ip_vs_proto_tcp.c
1 /*
2  * ip_vs_proto_tcp.c:   TCP load balancing support for IPVS
3  *
4  * Version:     $Id: ip_vs_proto_tcp.c,v 1.3 2002/11/30 01:50:35 wensong Exp $
5  *
6  * Authors:     Wensong Zhang <wensong@linuxvirtualserver.org>
7  *              Julian Anastasov <ja@ssi.bg>
8  *
9  *              This program is free software; you can redistribute it and/or
10  *              modify it under the terms of the GNU General Public License
11  *              as published by the Free Software Foundation; either version
12  *              2 of the License, or (at your option) any later version.
13  *
14  * Changes:
15  *
16  */
17
18 #include <linux/kernel.h>
19 #include <linux/ip.h>
20 #include <linux/tcp.h>                  /* for tcphdr */
21 #include <net/ip.h>
22 #include <net/tcp.h>                    /* for csum_tcpudp_magic */
23 #include <linux/netfilter_ipv4.h>
24
25 #include <net/ip_vs.h>
26
27
28 static struct ip_vs_conn *
29 tcp_conn_in_get(const struct sk_buff *skb, struct ip_vs_protocol *pp,
30                 const struct iphdr *iph, unsigned int proto_off, int inverse)
31 {
32         __be16 _ports[2], *pptr;
33
34         pptr = skb_header_pointer(skb, proto_off, sizeof(_ports), _ports);
35         if (pptr == NULL)
36                 return NULL;
37
38         if (likely(!inverse)) {
39                 return ip_vs_conn_in_get(iph->protocol,
40                                          iph->saddr, pptr[0],
41                                          iph->daddr, pptr[1]);
42         } else {
43                 return ip_vs_conn_in_get(iph->protocol,
44                                          iph->daddr, pptr[1],
45                                          iph->saddr, pptr[0]);
46         }
47 }
48
49 static struct ip_vs_conn *
50 tcp_conn_out_get(const struct sk_buff *skb, struct ip_vs_protocol *pp,
51                  const struct iphdr *iph, unsigned int proto_off, int inverse)
52 {
53         __be16 _ports[2], *pptr;
54
55         pptr = skb_header_pointer(skb, proto_off, sizeof(_ports), _ports);
56         if (pptr == NULL)
57                 return NULL;
58
59         if (likely(!inverse)) {
60                 return ip_vs_conn_out_get(iph->protocol,
61                                           iph->saddr, pptr[0],
62                                           iph->daddr, pptr[1]);
63         } else {
64                 return ip_vs_conn_out_get(iph->protocol,
65                                           iph->daddr, pptr[1],
66                                           iph->saddr, pptr[0]);
67         }
68 }
69
70
71 static int
72 tcp_conn_schedule(struct sk_buff *skb,
73                   struct ip_vs_protocol *pp,
74                   int *verdict, struct ip_vs_conn **cpp)
75 {
76         struct ip_vs_service *svc;
77         struct tcphdr _tcph, *th;
78
79         th = skb_header_pointer(skb, skb->nh.iph->ihl*4,
80                                 sizeof(_tcph), &_tcph);
81         if (th == NULL) {
82                 *verdict = NF_DROP;
83                 return 0;
84         }
85
86         if (th->syn &&
87             (svc = ip_vs_service_get(skb->nfmark, skb->nh.iph->protocol,
88                                      skb->nh.iph->daddr, th->dest))) {
89                 if (ip_vs_todrop()) {
90                         /*
91                          * It seems that we are very loaded.
92                          * We have to drop this packet :(
93                          */
94                         ip_vs_service_put(svc);
95                         *verdict = NF_DROP;
96                         return 0;
97                 }
98
99                 /*
100                  * Let the virtual server select a real server for the
101                  * incoming connection, and create a connection entry.
102                  */
103                 *cpp = ip_vs_schedule(svc, skb);
104                 if (!*cpp) {
105                         *verdict = ip_vs_leave(svc, skb, pp);
106                         return 0;
107                 }
108                 ip_vs_service_put(svc);
109         }
110         return 1;
111 }
112
113
114 static inline void
115 tcp_fast_csum_update(struct tcphdr *tcph, __be32 oldip, __be32 newip,
116                      __be16 oldport, __be16 newport)
117 {
118         tcph->check =
119                 ip_vs_check_diff(~oldip, newip,
120                                  ip_vs_check_diff(oldport ^ htons(0xFFFF),
121                                                   newport, tcph->check));
122 }
123
124
125 static int
126 tcp_snat_handler(struct sk_buff **pskb,
127                  struct ip_vs_protocol *pp, struct ip_vs_conn *cp)
128 {
129         struct tcphdr *tcph;
130         unsigned int tcphoff = (*pskb)->nh.iph->ihl * 4;
131
132         /* csum_check requires unshared skb */
133         if (!ip_vs_make_skb_writable(pskb, tcphoff+sizeof(*tcph)))
134                 return 0;
135
136         if (unlikely(cp->app != NULL)) {
137                 /* Some checks before mangling */
138                 if (pp->csum_check && !pp->csum_check(*pskb, pp))
139                         return 0;
140
141                 /* Call application helper if needed */
142                 if (!ip_vs_app_pkt_out(cp, pskb))
143                         return 0;
144         }
145
146         tcph = (void *)(*pskb)->nh.iph + tcphoff;
147         tcph->source = cp->vport;
148
149         /* Adjust TCP checksums */
150         if (!cp->app) {
151                 /* Only port and addr are changed, do fast csum update */
152                 tcp_fast_csum_update(tcph, cp->daddr, cp->vaddr,
153                                      cp->dport, cp->vport);
154                 if ((*pskb)->ip_summed == CHECKSUM_COMPLETE)
155                         (*pskb)->ip_summed = CHECKSUM_NONE;
156         } else {
157                 /* full checksum calculation */
158                 tcph->check = 0;
159                 (*pskb)->csum = skb_checksum(*pskb, tcphoff,
160                                              (*pskb)->len - tcphoff, 0);
161                 tcph->check = csum_tcpudp_magic(cp->vaddr, cp->caddr,
162                                                 (*pskb)->len - tcphoff,
163                                                 cp->protocol,
164                                                 (*pskb)->csum);
165                 IP_VS_DBG(11, "O-pkt: %s O-csum=%d (+%zd)\n",
166                           pp->name, tcph->check,
167                           (char*)&(tcph->check) - (char*)tcph);
168         }
169         return 1;
170 }
171
172
173 static int
174 tcp_dnat_handler(struct sk_buff **pskb,
175                  struct ip_vs_protocol *pp, struct ip_vs_conn *cp)
176 {
177         struct tcphdr *tcph;
178         unsigned int tcphoff = (*pskb)->nh.iph->ihl * 4;
179
180         /* csum_check requires unshared skb */
181         if (!ip_vs_make_skb_writable(pskb, tcphoff+sizeof(*tcph)))
182                 return 0;
183
184         if (unlikely(cp->app != NULL)) {
185                 /* Some checks before mangling */
186                 if (pp->csum_check && !pp->csum_check(*pskb, pp))
187                         return 0;
188
189                 /*
190                  *      Attempt ip_vs_app call.
191                  *      It will fix ip_vs_conn and iph ack_seq stuff
192                  */
193                 if (!ip_vs_app_pkt_in(cp, pskb))
194                         return 0;
195         }
196
197         tcph = (void *)(*pskb)->nh.iph + tcphoff;
198         tcph->dest = cp->dport;
199
200         /*
201          *      Adjust TCP checksums
202          */
203         if (!cp->app) {
204                 /* Only port and addr are changed, do fast csum update */
205                 tcp_fast_csum_update(tcph, cp->vaddr, cp->daddr,
206                                      cp->vport, cp->dport);
207                 if ((*pskb)->ip_summed == CHECKSUM_COMPLETE)
208                         (*pskb)->ip_summed = CHECKSUM_NONE;
209         } else {
210                 /* full checksum calculation */
211                 tcph->check = 0;
212                 (*pskb)->csum = skb_checksum(*pskb, tcphoff,
213                                              (*pskb)->len - tcphoff, 0);
214                 tcph->check = csum_tcpudp_magic(cp->caddr, cp->daddr,
215                                                 (*pskb)->len - tcphoff,
216                                                 cp->protocol,
217                                                 (*pskb)->csum);
218                 (*pskb)->ip_summed = CHECKSUM_UNNECESSARY;
219         }
220         return 1;
221 }
222
223
224 static int
225 tcp_csum_check(struct sk_buff *skb, struct ip_vs_protocol *pp)
226 {
227         unsigned int tcphoff = skb->nh.iph->ihl*4;
228
229         switch (skb->ip_summed) {
230         case CHECKSUM_NONE:
231                 skb->csum = skb_checksum(skb, tcphoff, skb->len - tcphoff, 0);
232         case CHECKSUM_COMPLETE:
233                 if (csum_tcpudp_magic(skb->nh.iph->saddr, skb->nh.iph->daddr,
234                                       skb->len - tcphoff,
235                                       skb->nh.iph->protocol, skb->csum)) {
236                         IP_VS_DBG_RL_PKT(0, pp, skb, 0,
237                                          "Failed checksum for");
238                         return 0;
239                 }
240                 break;
241         default:
242                 /* No need to checksum. */
243                 break;
244         }
245
246         return 1;
247 }
248
249
250 #define TCP_DIR_INPUT           0
251 #define TCP_DIR_OUTPUT          4
252 #define TCP_DIR_INPUT_ONLY      8
253
254 static const int tcp_state_off[IP_VS_DIR_LAST] = {
255         [IP_VS_DIR_INPUT]               =       TCP_DIR_INPUT,
256         [IP_VS_DIR_OUTPUT]              =       TCP_DIR_OUTPUT,
257         [IP_VS_DIR_INPUT_ONLY]          =       TCP_DIR_INPUT_ONLY,
258 };
259
260 /*
261  *      Timeout table[state]
262  */
263 static int tcp_timeouts[IP_VS_TCP_S_LAST+1] = {
264         [IP_VS_TCP_S_NONE]              =       2*HZ,
265         [IP_VS_TCP_S_ESTABLISHED]       =       15*60*HZ,
266         [IP_VS_TCP_S_SYN_SENT]          =       2*60*HZ,
267         [IP_VS_TCP_S_SYN_RECV]          =       1*60*HZ,
268         [IP_VS_TCP_S_FIN_WAIT]          =       2*60*HZ,
269         [IP_VS_TCP_S_TIME_WAIT]         =       2*60*HZ,
270         [IP_VS_TCP_S_CLOSE]             =       10*HZ,
271         [IP_VS_TCP_S_CLOSE_WAIT]        =       60*HZ,
272         [IP_VS_TCP_S_LAST_ACK]          =       30*HZ,
273         [IP_VS_TCP_S_LISTEN]            =       2*60*HZ,
274         [IP_VS_TCP_S_SYNACK]            =       120*HZ,
275         [IP_VS_TCP_S_LAST]              =       2*HZ,
276 };
277
278 static char * tcp_state_name_table[IP_VS_TCP_S_LAST+1] = {
279         [IP_VS_TCP_S_NONE]              =       "NONE",
280         [IP_VS_TCP_S_ESTABLISHED]       =       "ESTABLISHED",
281         [IP_VS_TCP_S_SYN_SENT]          =       "SYN_SENT",
282         [IP_VS_TCP_S_SYN_RECV]          =       "SYN_RECV",
283         [IP_VS_TCP_S_FIN_WAIT]          =       "FIN_WAIT",
284         [IP_VS_TCP_S_TIME_WAIT]         =       "TIME_WAIT",
285         [IP_VS_TCP_S_CLOSE]             =       "CLOSE",
286         [IP_VS_TCP_S_CLOSE_WAIT]        =       "CLOSE_WAIT",
287         [IP_VS_TCP_S_LAST_ACK]          =       "LAST_ACK",
288         [IP_VS_TCP_S_LISTEN]            =       "LISTEN",
289         [IP_VS_TCP_S_SYNACK]            =       "SYNACK",
290         [IP_VS_TCP_S_LAST]              =       "BUG!",
291 };
292
293 #define sNO IP_VS_TCP_S_NONE
294 #define sES IP_VS_TCP_S_ESTABLISHED
295 #define sSS IP_VS_TCP_S_SYN_SENT
296 #define sSR IP_VS_TCP_S_SYN_RECV
297 #define sFW IP_VS_TCP_S_FIN_WAIT
298 #define sTW IP_VS_TCP_S_TIME_WAIT
299 #define sCL IP_VS_TCP_S_CLOSE
300 #define sCW IP_VS_TCP_S_CLOSE_WAIT
301 #define sLA IP_VS_TCP_S_LAST_ACK
302 #define sLI IP_VS_TCP_S_LISTEN
303 #define sSA IP_VS_TCP_S_SYNACK
304
305 struct tcp_states_t {
306         int next_state[IP_VS_TCP_S_LAST];
307 };
308
309 static const char * tcp_state_name(int state)
310 {
311         if (state >= IP_VS_TCP_S_LAST)
312                 return "ERR!";
313         return tcp_state_name_table[state] ? tcp_state_name_table[state] : "?";
314 }
315
316 static struct tcp_states_t tcp_states [] = {
317 /*      INPUT */
318 /*        sNO, sES, sSS, sSR, sFW, sTW, sCL, sCW, sLA, sLI, sSA */
319 /*syn*/ {{sSR, sES, sES, sSR, sSR, sSR, sSR, sSR, sSR, sSR, sSR }},
320 /*fin*/ {{sCL, sCW, sSS, sTW, sTW, sTW, sCL, sCW, sLA, sLI, sTW }},
321 /*ack*/ {{sCL, sES, sSS, sES, sFW, sTW, sCL, sCW, sCL, sLI, sES }},
322 /*rst*/ {{sCL, sCL, sCL, sSR, sCL, sCL, sCL, sCL, sLA, sLI, sSR }},
323
324 /*      OUTPUT */
325 /*        sNO, sES, sSS, sSR, sFW, sTW, sCL, sCW, sLA, sLI, sSA */
326 /*syn*/ {{sSS, sES, sSS, sSR, sSS, sSS, sSS, sSS, sSS, sLI, sSR }},
327 /*fin*/ {{sTW, sFW, sSS, sTW, sFW, sTW, sCL, sTW, sLA, sLI, sTW }},
328 /*ack*/ {{sES, sES, sSS, sES, sFW, sTW, sCL, sCW, sLA, sES, sES }},
329 /*rst*/ {{sCL, sCL, sSS, sCL, sCL, sTW, sCL, sCL, sCL, sCL, sCL }},
330
331 /*      INPUT-ONLY */
332 /*        sNO, sES, sSS, sSR, sFW, sTW, sCL, sCW, sLA, sLI, sSA */
333 /*syn*/ {{sSR, sES, sES, sSR, sSR, sSR, sSR, sSR, sSR, sSR, sSR }},
334 /*fin*/ {{sCL, sFW, sSS, sTW, sFW, sTW, sCL, sCW, sLA, sLI, sTW }},
335 /*ack*/ {{sCL, sES, sSS, sES, sFW, sTW, sCL, sCW, sCL, sLI, sES }},
336 /*rst*/ {{sCL, sCL, sCL, sSR, sCL, sCL, sCL, sCL, sLA, sLI, sCL }},
337 };
338
339 static struct tcp_states_t tcp_states_dos [] = {
340 /*      INPUT */
341 /*        sNO, sES, sSS, sSR, sFW, sTW, sCL, sCW, sLA, sLI, sSA */
342 /*syn*/ {{sSR, sES, sES, sSR, sSR, sSR, sSR, sSR, sSR, sSR, sSA }},
343 /*fin*/ {{sCL, sCW, sSS, sTW, sTW, sTW, sCL, sCW, sLA, sLI, sSA }},
344 /*ack*/ {{sCL, sES, sSS, sSR, sFW, sTW, sCL, sCW, sCL, sLI, sSA }},
345 /*rst*/ {{sCL, sCL, sCL, sSR, sCL, sCL, sCL, sCL, sLA, sLI, sCL }},
346
347 /*      OUTPUT */
348 /*        sNO, sES, sSS, sSR, sFW, sTW, sCL, sCW, sLA, sLI, sSA */
349 /*syn*/ {{sSS, sES, sSS, sSA, sSS, sSS, sSS, sSS, sSS, sLI, sSA }},
350 /*fin*/ {{sTW, sFW, sSS, sTW, sFW, sTW, sCL, sTW, sLA, sLI, sTW }},
351 /*ack*/ {{sES, sES, sSS, sES, sFW, sTW, sCL, sCW, sLA, sES, sES }},
352 /*rst*/ {{sCL, sCL, sSS, sCL, sCL, sTW, sCL, sCL, sCL, sCL, sCL }},
353
354 /*      INPUT-ONLY */
355 /*        sNO, sES, sSS, sSR, sFW, sTW, sCL, sCW, sLA, sLI, sSA */
356 /*syn*/ {{sSA, sES, sES, sSR, sSA, sSA, sSA, sSA, sSA, sSA, sSA }},
357 /*fin*/ {{sCL, sFW, sSS, sTW, sFW, sTW, sCL, sCW, sLA, sLI, sTW }},
358 /*ack*/ {{sCL, sES, sSS, sES, sFW, sTW, sCL, sCW, sCL, sLI, sES }},
359 /*rst*/ {{sCL, sCL, sCL, sSR, sCL, sCL, sCL, sCL, sLA, sLI, sCL }},
360 };
361
362 static struct tcp_states_t *tcp_state_table = tcp_states;
363
364
365 static void tcp_timeout_change(struct ip_vs_protocol *pp, int flags)
366 {
367         int on = (flags & 1);           /* secure_tcp */
368
369         /*
370         ** FIXME: change secure_tcp to independent sysctl var
371         ** or make it per-service or per-app because it is valid
372         ** for most if not for all of the applications. Something
373         ** like "capabilities" (flags) for each object.
374         */
375         tcp_state_table = (on? tcp_states_dos : tcp_states);
376 }
377
378 static int
379 tcp_set_state_timeout(struct ip_vs_protocol *pp, char *sname, int to)
380 {
381         return ip_vs_set_state_timeout(pp->timeout_table, IP_VS_TCP_S_LAST,
382                                        tcp_state_name_table, sname, to);
383 }
384
385 static inline int tcp_state_idx(struct tcphdr *th)
386 {
387         if (th->rst)
388                 return 3;
389         if (th->syn)
390                 return 0;
391         if (th->fin)
392                 return 1;
393         if (th->ack)
394                 return 2;
395         return -1;
396 }
397
398 static inline void
399 set_tcp_state(struct ip_vs_protocol *pp, struct ip_vs_conn *cp,
400               int direction, struct tcphdr *th)
401 {
402         int state_idx;
403         int new_state = IP_VS_TCP_S_CLOSE;
404         int state_off = tcp_state_off[direction];
405
406         /*
407          *    Update state offset to INPUT_ONLY if necessary
408          *    or delete NO_OUTPUT flag if output packet detected
409          */
410         if (cp->flags & IP_VS_CONN_F_NOOUTPUT) {
411                 if (state_off == TCP_DIR_OUTPUT)
412                         cp->flags &= ~IP_VS_CONN_F_NOOUTPUT;
413                 else
414                         state_off = TCP_DIR_INPUT_ONLY;
415         }
416
417         if ((state_idx = tcp_state_idx(th)) < 0) {
418                 IP_VS_DBG(8, "tcp_state_idx=%d!!!\n", state_idx);
419                 goto tcp_state_out;
420         }
421
422         new_state = tcp_state_table[state_off+state_idx].next_state[cp->state];
423
424   tcp_state_out:
425         if (new_state != cp->state) {
426                 struct ip_vs_dest *dest = cp->dest;
427
428                 IP_VS_DBG(8, "%s %s [%c%c%c%c] %u.%u.%u.%u:%d->"
429                           "%u.%u.%u.%u:%d state: %s->%s conn->refcnt:%d\n",
430                           pp->name,
431                           (state_off==TCP_DIR_OUTPUT)?"output ":"input ",
432                           th->syn? 'S' : '.',
433                           th->fin? 'F' : '.',
434                           th->ack? 'A' : '.',
435                           th->rst? 'R' : '.',
436                           NIPQUAD(cp->daddr), ntohs(cp->dport),
437                           NIPQUAD(cp->caddr), ntohs(cp->cport),
438                           tcp_state_name(cp->state),
439                           tcp_state_name(new_state),
440                           atomic_read(&cp->refcnt));
441                 if (dest) {
442                         if (!(cp->flags & IP_VS_CONN_F_INACTIVE) &&
443                             (new_state != IP_VS_TCP_S_ESTABLISHED)) {
444                                 atomic_dec(&dest->activeconns);
445                                 atomic_inc(&dest->inactconns);
446                                 cp->flags |= IP_VS_CONN_F_INACTIVE;
447                         } else if ((cp->flags & IP_VS_CONN_F_INACTIVE) &&
448                                    (new_state == IP_VS_TCP_S_ESTABLISHED)) {
449                                 atomic_inc(&dest->activeconns);
450                                 atomic_dec(&dest->inactconns);
451                                 cp->flags &= ~IP_VS_CONN_F_INACTIVE;
452                         }
453                 }
454         }
455
456         cp->timeout = pp->timeout_table[cp->state = new_state];
457 }
458
459
460 /*
461  *      Handle state transitions
462  */
463 static int
464 tcp_state_transition(struct ip_vs_conn *cp, int direction,
465                      const struct sk_buff *skb,
466                      struct ip_vs_protocol *pp)
467 {
468         struct tcphdr _tcph, *th;
469
470         th = skb_header_pointer(skb, skb->nh.iph->ihl*4,
471                                 sizeof(_tcph), &_tcph);
472         if (th == NULL)
473                 return 0;
474
475         spin_lock(&cp->lock);
476         set_tcp_state(pp, cp, direction, th);
477         spin_unlock(&cp->lock);
478
479         return 1;
480 }
481
482
483 /*
484  *      Hash table for TCP application incarnations
485  */
486 #define TCP_APP_TAB_BITS        4
487 #define TCP_APP_TAB_SIZE        (1 << TCP_APP_TAB_BITS)
488 #define TCP_APP_TAB_MASK        (TCP_APP_TAB_SIZE - 1)
489
490 static struct list_head tcp_apps[TCP_APP_TAB_SIZE];
491 static DEFINE_SPINLOCK(tcp_app_lock);
492
493 static inline __u16 tcp_app_hashkey(__u16 port)
494 {
495         return ((port >> TCP_APP_TAB_BITS) ^ port) & TCP_APP_TAB_MASK;
496 }
497
498
499 static int tcp_register_app(struct ip_vs_app *inc)
500 {
501         struct ip_vs_app *i;
502         __u16 hash, port = inc->port;
503         int ret = 0;
504
505         hash = tcp_app_hashkey(port);
506
507         spin_lock_bh(&tcp_app_lock);
508         list_for_each_entry(i, &tcp_apps[hash], p_list) {
509                 if (i->port == port) {
510                         ret = -EEXIST;
511                         goto out;
512                 }
513         }
514         list_add(&inc->p_list, &tcp_apps[hash]);
515         atomic_inc(&ip_vs_protocol_tcp.appcnt);
516
517   out:
518         spin_unlock_bh(&tcp_app_lock);
519         return ret;
520 }
521
522
523 static void
524 tcp_unregister_app(struct ip_vs_app *inc)
525 {
526         spin_lock_bh(&tcp_app_lock);
527         atomic_dec(&ip_vs_protocol_tcp.appcnt);
528         list_del(&inc->p_list);
529         spin_unlock_bh(&tcp_app_lock);
530 }
531
532
533 static int
534 tcp_app_conn_bind(struct ip_vs_conn *cp)
535 {
536         int hash;
537         struct ip_vs_app *inc;
538         int result = 0;
539
540         /* Default binding: bind app only for NAT */
541         if (IP_VS_FWD_METHOD(cp) != IP_VS_CONN_F_MASQ)
542                 return 0;
543
544         /* Lookup application incarnations and bind the right one */
545         hash = tcp_app_hashkey(cp->vport);
546
547         spin_lock(&tcp_app_lock);
548         list_for_each_entry(inc, &tcp_apps[hash], p_list) {
549                 if (inc->port == cp->vport) {
550                         if (unlikely(!ip_vs_app_inc_get(inc)))
551                                 break;
552                         spin_unlock(&tcp_app_lock);
553
554                         IP_VS_DBG(9, "%s: Binding conn %u.%u.%u.%u:%u->"
555                                   "%u.%u.%u.%u:%u to app %s on port %u\n",
556                                   __FUNCTION__,
557                                   NIPQUAD(cp->caddr), ntohs(cp->cport),
558                                   NIPQUAD(cp->vaddr), ntohs(cp->vport),
559                                   inc->name, ntohs(inc->port));
560                         cp->app = inc;
561                         if (inc->init_conn)
562                                 result = inc->init_conn(inc, cp);
563                         goto out;
564                 }
565         }
566         spin_unlock(&tcp_app_lock);
567
568   out:
569         return result;
570 }
571
572
573 /*
574  *      Set LISTEN timeout. (ip_vs_conn_put will setup timer)
575  */
576 void ip_vs_tcp_conn_listen(struct ip_vs_conn *cp)
577 {
578         spin_lock(&cp->lock);
579         cp->state = IP_VS_TCP_S_LISTEN;
580         cp->timeout = ip_vs_protocol_tcp.timeout_table[IP_VS_TCP_S_LISTEN];
581         spin_unlock(&cp->lock);
582 }
583
584
585 static void ip_vs_tcp_init(struct ip_vs_protocol *pp)
586 {
587         IP_VS_INIT_HASH_TABLE(tcp_apps);
588         pp->timeout_table = tcp_timeouts;
589 }
590
591
592 static void ip_vs_tcp_exit(struct ip_vs_protocol *pp)
593 {
594 }
595
596
597 struct ip_vs_protocol ip_vs_protocol_tcp = {
598         .name =                 "TCP",
599         .protocol =             IPPROTO_TCP,
600         .dont_defrag =          0,
601         .appcnt =               ATOMIC_INIT(0),
602         .init =                 ip_vs_tcp_init,
603         .exit =                 ip_vs_tcp_exit,
604         .register_app =         tcp_register_app,
605         .unregister_app =       tcp_unregister_app,
606         .conn_schedule =        tcp_conn_schedule,
607         .conn_in_get =          tcp_conn_in_get,
608         .conn_out_get =         tcp_conn_out_get,
609         .snat_handler =         tcp_snat_handler,
610         .dnat_handler =         tcp_dnat_handler,
611         .csum_check =           tcp_csum_check,
612         .state_name =           tcp_state_name,
613         .state_transition =     tcp_state_transition,
614         .app_conn_bind =        tcp_app_conn_bind,
615         .debug_packet =         ip_vs_tcpudp_debug_packet,
616         .timeout_change =       tcp_timeout_change,
617         .set_state_timeout =    tcp_set_state_timeout,
618 };