Merge branch 'juju' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux13...
[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, ip_hdrlen(skb), sizeof(_tcph), &_tcph);
80         if (th == NULL) {
81                 *verdict = NF_DROP;
82                 return 0;
83         }
84
85         if (th->syn &&
86             (svc = ip_vs_service_get(skb->mark, ip_hdr(skb)->protocol,
87                                      ip_hdr(skb)->daddr, th->dest))) {
88                 if (ip_vs_todrop()) {
89                         /*
90                          * It seems that we are very loaded.
91                          * We have to drop this packet :(
92                          */
93                         ip_vs_service_put(svc);
94                         *verdict = NF_DROP;
95                         return 0;
96                 }
97
98                 /*
99                  * Let the virtual server select a real server for the
100                  * incoming connection, and create a connection entry.
101                  */
102                 *cpp = ip_vs_schedule(svc, skb);
103                 if (!*cpp) {
104                         *verdict = ip_vs_leave(svc, skb, pp);
105                         return 0;
106                 }
107                 ip_vs_service_put(svc);
108         }
109         return 1;
110 }
111
112
113 static inline void
114 tcp_fast_csum_update(struct tcphdr *tcph, __be32 oldip, __be32 newip,
115                      __be16 oldport, __be16 newport)
116 {
117         tcph->check =
118                 csum_fold(ip_vs_check_diff4(oldip, newip,
119                                  ip_vs_check_diff2(oldport, newport,
120                                                 ~csum_unfold(tcph->check))));
121 }
122
123
124 static int
125 tcp_snat_handler(struct sk_buff **pskb,
126                  struct ip_vs_protocol *pp, struct ip_vs_conn *cp)
127 {
128         struct tcphdr *tcph;
129         const unsigned int tcphoff = ip_hdrlen(*pskb);
130
131         /* csum_check requires unshared skb */
132         if (!ip_vs_make_skb_writable(pskb, tcphoff+sizeof(*tcph)))
133                 return 0;
134
135         if (unlikely(cp->app != NULL)) {
136                 /* Some checks before mangling */
137                 if (pp->csum_check && !pp->csum_check(*pskb, pp))
138                         return 0;
139
140                 /* Call application helper if needed */
141                 if (!ip_vs_app_pkt_out(cp, pskb))
142                         return 0;
143         }
144
145         tcph = (void *)ip_hdr(*pskb) + tcphoff;
146         tcph->source = cp->vport;
147
148         /* Adjust TCP checksums */
149         if (!cp->app) {
150                 /* Only port and addr are changed, do fast csum update */
151                 tcp_fast_csum_update(tcph, cp->daddr, cp->vaddr,
152                                      cp->dport, cp->vport);
153                 if ((*pskb)->ip_summed == CHECKSUM_COMPLETE)
154                         (*pskb)->ip_summed = CHECKSUM_NONE;
155         } else {
156                 /* full checksum calculation */
157                 tcph->check = 0;
158                 (*pskb)->csum = skb_checksum(*pskb, tcphoff,
159                                              (*pskb)->len - tcphoff, 0);
160                 tcph->check = csum_tcpudp_magic(cp->vaddr, cp->caddr,
161                                                 (*pskb)->len - tcphoff,
162                                                 cp->protocol,
163                                                 (*pskb)->csum);
164                 IP_VS_DBG(11, "O-pkt: %s O-csum=%d (+%zd)\n",
165                           pp->name, tcph->check,
166                           (char*)&(tcph->check) - (char*)tcph);
167         }
168         return 1;
169 }
170
171
172 static int
173 tcp_dnat_handler(struct sk_buff **pskb,
174                  struct ip_vs_protocol *pp, struct ip_vs_conn *cp)
175 {
176         struct tcphdr *tcph;
177         const unsigned int tcphoff = ip_hdrlen(*pskb);
178
179         /* csum_check requires unshared skb */
180         if (!ip_vs_make_skb_writable(pskb, tcphoff+sizeof(*tcph)))
181                 return 0;
182
183         if (unlikely(cp->app != NULL)) {
184                 /* Some checks before mangling */
185                 if (pp->csum_check && !pp->csum_check(*pskb, pp))
186                         return 0;
187
188                 /*
189                  *      Attempt ip_vs_app call.
190                  *      It will fix ip_vs_conn and iph ack_seq stuff
191                  */
192                 if (!ip_vs_app_pkt_in(cp, pskb))
193                         return 0;
194         }
195
196         tcph = (void *)ip_hdr(*pskb) + tcphoff;
197         tcph->dest = cp->dport;
198
199         /*
200          *      Adjust TCP checksums
201          */
202         if (!cp->app) {
203                 /* Only port and addr are changed, do fast csum update */
204                 tcp_fast_csum_update(tcph, cp->vaddr, cp->daddr,
205                                      cp->vport, cp->dport);
206                 if ((*pskb)->ip_summed == CHECKSUM_COMPLETE)
207                         (*pskb)->ip_summed = CHECKSUM_NONE;
208         } else {
209                 /* full checksum calculation */
210                 tcph->check = 0;
211                 (*pskb)->csum = skb_checksum(*pskb, tcphoff,
212                                              (*pskb)->len - tcphoff, 0);
213                 tcph->check = csum_tcpudp_magic(cp->caddr, cp->daddr,
214                                                 (*pskb)->len - tcphoff,
215                                                 cp->protocol,
216                                                 (*pskb)->csum);
217                 (*pskb)->ip_summed = CHECKSUM_UNNECESSARY;
218         }
219         return 1;
220 }
221
222
223 static int
224 tcp_csum_check(struct sk_buff *skb, struct ip_vs_protocol *pp)
225 {
226         const unsigned int tcphoff = ip_hdrlen(skb);
227
228         switch (skb->ip_summed) {
229         case CHECKSUM_NONE:
230                 skb->csum = skb_checksum(skb, tcphoff, skb->len - tcphoff, 0);
231         case CHECKSUM_COMPLETE:
232                 if (csum_tcpudp_magic(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr,
233                                       skb->len - tcphoff,
234                                       ip_hdr(skb)->protocol, skb->csum)) {
235                         IP_VS_DBG_RL_PKT(0, pp, skb, 0,
236                                          "Failed checksum for");
237                         return 0;
238                 }
239                 break;
240         default:
241                 /* No need to checksum. */
242                 break;
243         }
244
245         return 1;
246 }
247
248
249 #define TCP_DIR_INPUT           0
250 #define TCP_DIR_OUTPUT          4
251 #define TCP_DIR_INPUT_ONLY      8
252
253 static const int tcp_state_off[IP_VS_DIR_LAST] = {
254         [IP_VS_DIR_INPUT]               =       TCP_DIR_INPUT,
255         [IP_VS_DIR_OUTPUT]              =       TCP_DIR_OUTPUT,
256         [IP_VS_DIR_INPUT_ONLY]          =       TCP_DIR_INPUT_ONLY,
257 };
258
259 /*
260  *      Timeout table[state]
261  */
262 static int tcp_timeouts[IP_VS_TCP_S_LAST+1] = {
263         [IP_VS_TCP_S_NONE]              =       2*HZ,
264         [IP_VS_TCP_S_ESTABLISHED]       =       15*60*HZ,
265         [IP_VS_TCP_S_SYN_SENT]          =       2*60*HZ,
266         [IP_VS_TCP_S_SYN_RECV]          =       1*60*HZ,
267         [IP_VS_TCP_S_FIN_WAIT]          =       2*60*HZ,
268         [IP_VS_TCP_S_TIME_WAIT]         =       2*60*HZ,
269         [IP_VS_TCP_S_CLOSE]             =       10*HZ,
270         [IP_VS_TCP_S_CLOSE_WAIT]        =       60*HZ,
271         [IP_VS_TCP_S_LAST_ACK]          =       30*HZ,
272         [IP_VS_TCP_S_LISTEN]            =       2*60*HZ,
273         [IP_VS_TCP_S_SYNACK]            =       120*HZ,
274         [IP_VS_TCP_S_LAST]              =       2*HZ,
275 };
276
277 static char * tcp_state_name_table[IP_VS_TCP_S_LAST+1] = {
278         [IP_VS_TCP_S_NONE]              =       "NONE",
279         [IP_VS_TCP_S_ESTABLISHED]       =       "ESTABLISHED",
280         [IP_VS_TCP_S_SYN_SENT]          =       "SYN_SENT",
281         [IP_VS_TCP_S_SYN_RECV]          =       "SYN_RECV",
282         [IP_VS_TCP_S_FIN_WAIT]          =       "FIN_WAIT",
283         [IP_VS_TCP_S_TIME_WAIT]         =       "TIME_WAIT",
284         [IP_VS_TCP_S_CLOSE]             =       "CLOSE",
285         [IP_VS_TCP_S_CLOSE_WAIT]        =       "CLOSE_WAIT",
286         [IP_VS_TCP_S_LAST_ACK]          =       "LAST_ACK",
287         [IP_VS_TCP_S_LISTEN]            =       "LISTEN",
288         [IP_VS_TCP_S_SYNACK]            =       "SYNACK",
289         [IP_VS_TCP_S_LAST]              =       "BUG!",
290 };
291
292 #define sNO IP_VS_TCP_S_NONE
293 #define sES IP_VS_TCP_S_ESTABLISHED
294 #define sSS IP_VS_TCP_S_SYN_SENT
295 #define sSR IP_VS_TCP_S_SYN_RECV
296 #define sFW IP_VS_TCP_S_FIN_WAIT
297 #define sTW IP_VS_TCP_S_TIME_WAIT
298 #define sCL IP_VS_TCP_S_CLOSE
299 #define sCW IP_VS_TCP_S_CLOSE_WAIT
300 #define sLA IP_VS_TCP_S_LAST_ACK
301 #define sLI IP_VS_TCP_S_LISTEN
302 #define sSA IP_VS_TCP_S_SYNACK
303
304 struct tcp_states_t {
305         int next_state[IP_VS_TCP_S_LAST];
306 };
307
308 static const char * tcp_state_name(int state)
309 {
310         if (state >= IP_VS_TCP_S_LAST)
311                 return "ERR!";
312         return tcp_state_name_table[state] ? tcp_state_name_table[state] : "?";
313 }
314
315 static struct tcp_states_t tcp_states [] = {
316 /*      INPUT */
317 /*        sNO, sES, sSS, sSR, sFW, sTW, sCL, sCW, sLA, sLI, sSA */
318 /*syn*/ {{sSR, sES, sES, sSR, sSR, sSR, sSR, sSR, sSR, sSR, sSR }},
319 /*fin*/ {{sCL, sCW, sSS, sTW, sTW, sTW, sCL, sCW, sLA, sLI, sTW }},
320 /*ack*/ {{sCL, sES, sSS, sES, sFW, sTW, sCL, sCW, sCL, sLI, sES }},
321 /*rst*/ {{sCL, sCL, sCL, sSR, sCL, sCL, sCL, sCL, sLA, sLI, sSR }},
322
323 /*      OUTPUT */
324 /*        sNO, sES, sSS, sSR, sFW, sTW, sCL, sCW, sLA, sLI, sSA */
325 /*syn*/ {{sSS, sES, sSS, sSR, sSS, sSS, sSS, sSS, sSS, sLI, sSR }},
326 /*fin*/ {{sTW, sFW, sSS, sTW, sFW, sTW, sCL, sTW, sLA, sLI, sTW }},
327 /*ack*/ {{sES, sES, sSS, sES, sFW, sTW, sCL, sCW, sLA, sES, sES }},
328 /*rst*/ {{sCL, sCL, sSS, sCL, sCL, sTW, sCL, sCL, sCL, sCL, sCL }},
329
330 /*      INPUT-ONLY */
331 /*        sNO, sES, sSS, sSR, sFW, sTW, sCL, sCW, sLA, sLI, sSA */
332 /*syn*/ {{sSR, sES, sES, sSR, sSR, sSR, sSR, sSR, sSR, sSR, sSR }},
333 /*fin*/ {{sCL, sFW, sSS, sTW, sFW, sTW, sCL, sCW, sLA, sLI, sTW }},
334 /*ack*/ {{sCL, sES, sSS, sES, sFW, sTW, sCL, sCW, sCL, sLI, sES }},
335 /*rst*/ {{sCL, sCL, sCL, sSR, sCL, sCL, sCL, sCL, sLA, sLI, sCL }},
336 };
337
338 static struct tcp_states_t tcp_states_dos [] = {
339 /*      INPUT */
340 /*        sNO, sES, sSS, sSR, sFW, sTW, sCL, sCW, sLA, sLI, sSA */
341 /*syn*/ {{sSR, sES, sES, sSR, sSR, sSR, sSR, sSR, sSR, sSR, sSA }},
342 /*fin*/ {{sCL, sCW, sSS, sTW, sTW, sTW, sCL, sCW, sLA, sLI, sSA }},
343 /*ack*/ {{sCL, sES, sSS, sSR, sFW, sTW, sCL, sCW, sCL, sLI, sSA }},
344 /*rst*/ {{sCL, sCL, sCL, sSR, sCL, sCL, sCL, sCL, sLA, sLI, sCL }},
345
346 /*      OUTPUT */
347 /*        sNO, sES, sSS, sSR, sFW, sTW, sCL, sCW, sLA, sLI, sSA */
348 /*syn*/ {{sSS, sES, sSS, sSA, sSS, sSS, sSS, sSS, sSS, sLI, sSA }},
349 /*fin*/ {{sTW, sFW, sSS, sTW, sFW, sTW, sCL, sTW, sLA, sLI, sTW }},
350 /*ack*/ {{sES, sES, sSS, sES, sFW, sTW, sCL, sCW, sLA, sES, sES }},
351 /*rst*/ {{sCL, sCL, sSS, sCL, sCL, sTW, sCL, sCL, sCL, sCL, sCL }},
352
353 /*      INPUT-ONLY */
354 /*        sNO, sES, sSS, sSR, sFW, sTW, sCL, sCW, sLA, sLI, sSA */
355 /*syn*/ {{sSA, sES, sES, sSR, sSA, sSA, sSA, sSA, sSA, sSA, sSA }},
356 /*fin*/ {{sCL, sFW, sSS, sTW, sFW, sTW, sCL, sCW, sLA, sLI, sTW }},
357 /*ack*/ {{sCL, sES, sSS, sES, sFW, sTW, sCL, sCW, sCL, sLI, sES }},
358 /*rst*/ {{sCL, sCL, sCL, sSR, sCL, sCL, sCL, sCL, sLA, sLI, sCL }},
359 };
360
361 static struct tcp_states_t *tcp_state_table = tcp_states;
362
363
364 static void tcp_timeout_change(struct ip_vs_protocol *pp, int flags)
365 {
366         int on = (flags & 1);           /* secure_tcp */
367
368         /*
369         ** FIXME: change secure_tcp to independent sysctl var
370         ** or make it per-service or per-app because it is valid
371         ** for most if not for all of the applications. Something
372         ** like "capabilities" (flags) for each object.
373         */
374         tcp_state_table = (on? tcp_states_dos : tcp_states);
375 }
376
377 static int
378 tcp_set_state_timeout(struct ip_vs_protocol *pp, char *sname, int to)
379 {
380         return ip_vs_set_state_timeout(pp->timeout_table, IP_VS_TCP_S_LAST,
381                                        tcp_state_name_table, sname, to);
382 }
383
384 static inline int tcp_state_idx(struct tcphdr *th)
385 {
386         if (th->rst)
387                 return 3;
388         if (th->syn)
389                 return 0;
390         if (th->fin)
391                 return 1;
392         if (th->ack)
393                 return 2;
394         return -1;
395 }
396
397 static inline void
398 set_tcp_state(struct ip_vs_protocol *pp, struct ip_vs_conn *cp,
399               int direction, struct tcphdr *th)
400 {
401         int state_idx;
402         int new_state = IP_VS_TCP_S_CLOSE;
403         int state_off = tcp_state_off[direction];
404
405         /*
406          *    Update state offset to INPUT_ONLY if necessary
407          *    or delete NO_OUTPUT flag if output packet detected
408          */
409         if (cp->flags & IP_VS_CONN_F_NOOUTPUT) {
410                 if (state_off == TCP_DIR_OUTPUT)
411                         cp->flags &= ~IP_VS_CONN_F_NOOUTPUT;
412                 else
413                         state_off = TCP_DIR_INPUT_ONLY;
414         }
415
416         if ((state_idx = tcp_state_idx(th)) < 0) {
417                 IP_VS_DBG(8, "tcp_state_idx=%d!!!\n", state_idx);
418                 goto tcp_state_out;
419         }
420
421         new_state = tcp_state_table[state_off+state_idx].next_state[cp->state];
422
423   tcp_state_out:
424         if (new_state != cp->state) {
425                 struct ip_vs_dest *dest = cp->dest;
426
427                 IP_VS_DBG(8, "%s %s [%c%c%c%c] %u.%u.%u.%u:%d->"
428                           "%u.%u.%u.%u:%d state: %s->%s conn->refcnt:%d\n",
429                           pp->name,
430                           (state_off==TCP_DIR_OUTPUT)?"output ":"input ",
431                           th->syn? 'S' : '.',
432                           th->fin? 'F' : '.',
433                           th->ack? 'A' : '.',
434                           th->rst? 'R' : '.',
435                           NIPQUAD(cp->daddr), ntohs(cp->dport),
436                           NIPQUAD(cp->caddr), ntohs(cp->cport),
437                           tcp_state_name(cp->state),
438                           tcp_state_name(new_state),
439                           atomic_read(&cp->refcnt));
440                 if (dest) {
441                         if (!(cp->flags & IP_VS_CONN_F_INACTIVE) &&
442                             (new_state != IP_VS_TCP_S_ESTABLISHED)) {
443                                 atomic_dec(&dest->activeconns);
444                                 atomic_inc(&dest->inactconns);
445                                 cp->flags |= IP_VS_CONN_F_INACTIVE;
446                         } else if ((cp->flags & IP_VS_CONN_F_INACTIVE) &&
447                                    (new_state == IP_VS_TCP_S_ESTABLISHED)) {
448                                 atomic_inc(&dest->activeconns);
449                                 atomic_dec(&dest->inactconns);
450                                 cp->flags &= ~IP_VS_CONN_F_INACTIVE;
451                         }
452                 }
453         }
454
455         cp->timeout = pp->timeout_table[cp->state = new_state];
456 }
457
458
459 /*
460  *      Handle state transitions
461  */
462 static int
463 tcp_state_transition(struct ip_vs_conn *cp, int direction,
464                      const struct sk_buff *skb,
465                      struct ip_vs_protocol *pp)
466 {
467         struct tcphdr _tcph, *th;
468
469         th = skb_header_pointer(skb, ip_hdrlen(skb), sizeof(_tcph), &_tcph);
470         if (th == NULL)
471                 return 0;
472
473         spin_lock(&cp->lock);
474         set_tcp_state(pp, cp, direction, th);
475         spin_unlock(&cp->lock);
476
477         return 1;
478 }
479
480
481 /*
482  *      Hash table for TCP application incarnations
483  */
484 #define TCP_APP_TAB_BITS        4
485 #define TCP_APP_TAB_SIZE        (1 << TCP_APP_TAB_BITS)
486 #define TCP_APP_TAB_MASK        (TCP_APP_TAB_SIZE - 1)
487
488 static struct list_head tcp_apps[TCP_APP_TAB_SIZE];
489 static DEFINE_SPINLOCK(tcp_app_lock);
490
491 static inline __u16 tcp_app_hashkey(__be16 port)
492 {
493         return (((__force u16)port >> TCP_APP_TAB_BITS) ^ (__force u16)port)
494                 & TCP_APP_TAB_MASK;
495 }
496
497
498 static int tcp_register_app(struct ip_vs_app *inc)
499 {
500         struct ip_vs_app *i;
501         __u16 hash;
502         __be16 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 };