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[PATCH] fs/ocfs2/dlm/: make functions static
[linux-2.6.22.y-op.git] / net / dccp / proto.c
blob63b3fa20e14bbb718d3baa9a7a16c2bcb1a503bd
1 /*
2 * net/dccp/proto.c
3 *
4 * An implementation of the DCCP protocol
5 * Arnaldo Carvalho de Melo <acme@conectiva.com.br>
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 */
11
12 #include <linux/dccp.h>
13 #include <linux/module.h>
14 #include <linux/types.h>
15 #include <linux/sched.h>
16 #include <linux/kernel.h>
17 #include <linux/skbuff.h>
18 #include <linux/netdevice.h>
19 #include <linux/in.h>
20 #include <linux/if_arp.h>
21 #include <linux/init.h>
22 #include <linux/random.h>
23 #include <net/checksum.h>
24
25 #include <net/inet_sock.h>
26 #include <net/sock.h>
27 #include <net/xfrm.h>
28
29 #include <asm/semaphore.h>
30 #include <linux/spinlock.h>
31 #include <linux/timer.h>
32 #include <linux/delay.h>
33 #include <linux/poll.h>
34
35 #include "ccid.h"
36 #include "dccp.h"
37 #include "feat.h"
38
39 DEFINE_SNMP_STAT(struct dccp_mib, dccp_statistics) __read_mostly;
40
41 EXPORT_SYMBOL_GPL(dccp_statistics);
42
43 atomic_t dccp_orphan_count = ATOMIC_INIT(0);
44
45 EXPORT_SYMBOL_GPL(dccp_orphan_count);
46
47 struct inet_hashinfo __cacheline_aligned dccp_hashinfo = {
48 .lhash_lock = RW_LOCK_UNLOCKED,
49 .lhash_users = ATOMIC_INIT(0),
50 .lhash_wait = __WAIT_QUEUE_HEAD_INITIALIZER(dccp_hashinfo.lhash_wait),
51 };
52
53 EXPORT_SYMBOL_GPL(dccp_hashinfo);
54
55 /* the maximum queue length for tx in packets. 0 is no limit */
56 int sysctl_dccp_tx_qlen __read_mostly = 5;
57
58 void dccp_set_state(struct sock *sk, const int state)
59 {
60 const int oldstate = sk->sk_state;
61
62 dccp_pr_debug("%s(%p) %-10.10s -> %s\n",
63 dccp_role(sk), sk,
64 dccp_state_name(oldstate), dccp_state_name(state));
65 WARN_ON(state == oldstate);
66
67 switch (state) {
68 case DCCP_OPEN:
69 if (oldstate != DCCP_OPEN)
70 DCCP_INC_STATS(DCCP_MIB_CURRESTAB);
71 break;
72
73 case DCCP_CLOSED:
74 if (oldstate == DCCP_CLOSING || oldstate == DCCP_OPEN)
75 DCCP_INC_STATS(DCCP_MIB_ESTABRESETS);
76
77 sk->sk_prot->unhash(sk);
78 if (inet_csk(sk)->icsk_bind_hash != NULL &&
79 !(sk->sk_userlocks & SOCK_BINDPORT_LOCK))
80 inet_put_port(&dccp_hashinfo, sk);
81 /* fall through */
82 default:
83 if (oldstate == DCCP_OPEN)
84 DCCP_DEC_STATS(DCCP_MIB_CURRESTAB);
85 }
86
87 /* Change state AFTER socket is unhashed to avoid closed
88 * socket sitting in hash tables.
89 */
90 sk->sk_state = state;
91 }
92
93 EXPORT_SYMBOL_GPL(dccp_set_state);
94
95 void dccp_done(struct sock *sk)
96 {
97 dccp_set_state(sk, DCCP_CLOSED);
98 dccp_clear_xmit_timers(sk);
99
100 sk->sk_shutdown = SHUTDOWN_MASK;
101
102 if (!sock_flag(sk, SOCK_DEAD))
103 sk->sk_state_change(sk);
104 else
105 inet_csk_destroy_sock(sk);
106 }
107
108 EXPORT_SYMBOL_GPL(dccp_done);
109
110 const char *dccp_packet_name(const int type)
111 {
112 static const char *dccp_packet_names[] = {
113 [DCCP_PKT_REQUEST] = "REQUEST",
114 [DCCP_PKT_RESPONSE] = "RESPONSE",
115 [DCCP_PKT_DATA] = "DATA",
116 [DCCP_PKT_ACK] = "ACK",
117 [DCCP_PKT_DATAACK] = "DATAACK",
118 [DCCP_PKT_CLOSEREQ] = "CLOSEREQ",
119 [DCCP_PKT_CLOSE] = "CLOSE",
120 [DCCP_PKT_RESET] = "RESET",
121 [DCCP_PKT_SYNC] = "SYNC",
122 [DCCP_PKT_SYNCACK] = "SYNCACK",
123 };
124
125 if (type >= DCCP_NR_PKT_TYPES)
126 return "INVALID";
127 else
128 return dccp_packet_names[type];
129 }
130
131 EXPORT_SYMBOL_GPL(dccp_packet_name);
132
133 const char *dccp_state_name(const int state)
134 {
135 static char *dccp_state_names[] = {
136 [DCCP_OPEN] = "OPEN",
137 [DCCP_REQUESTING] = "REQUESTING",
138 [DCCP_PARTOPEN] = "PARTOPEN",
139 [DCCP_LISTEN] = "LISTEN",
140 [DCCP_RESPOND] = "RESPOND",
141 [DCCP_CLOSING] = "CLOSING",
142 [DCCP_TIME_WAIT] = "TIME_WAIT",
143 [DCCP_CLOSED] = "CLOSED",
144 };
145
146 if (state >= DCCP_MAX_STATES)
147 return "INVALID STATE!";
148 else
149 return dccp_state_names[state];
150 }
151
152 EXPORT_SYMBOL_GPL(dccp_state_name);
153
154 void dccp_hash(struct sock *sk)
155 {
156 inet_hash(&dccp_hashinfo, sk);
157 }
158
159 EXPORT_SYMBOL_GPL(dccp_hash);
160
161 void dccp_unhash(struct sock *sk)
162 {
163 inet_unhash(&dccp_hashinfo, sk);
164 }
165
166 EXPORT_SYMBOL_GPL(dccp_unhash);
167
168 int dccp_init_sock(struct sock *sk, const __u8 ctl_sock_initialized)
169 {
170 struct dccp_sock *dp = dccp_sk(sk);
171 struct dccp_minisock *dmsk = dccp_msk(sk);
172 struct inet_connection_sock *icsk = inet_csk(sk);
173
174 dccp_minisock_init(&dp->dccps_minisock);
175 do_gettimeofday(&dp->dccps_epoch);
176
177 /*
178 * FIXME: We're hardcoding the CCID, and doing this at this point makes
179 * the listening (master) sock get CCID control blocks, which is not
180 * necessary, but for now, to not mess with the test userspace apps,
181 * lets leave it here, later the real solution is to do this in a
182 * setsockopt(CCIDs-I-want/accept). -acme
183 */
184 if (likely(ctl_sock_initialized)) {
185 int rc = dccp_feat_init(dmsk);
186
187 if (rc)
188 return rc;
189
190 if (dmsk->dccpms_send_ack_vector) {
191 dp->dccps_hc_rx_ackvec = dccp_ackvec_alloc(GFP_KERNEL);
192 if (dp->dccps_hc_rx_ackvec == NULL)
193 return -ENOMEM;
194 }
195 dp->dccps_hc_rx_ccid = ccid_hc_rx_new(dmsk->dccpms_rx_ccid,
196 sk, GFP_KERNEL);
197 dp->dccps_hc_tx_ccid = ccid_hc_tx_new(dmsk->dccpms_tx_ccid,
198 sk, GFP_KERNEL);
199 if (unlikely(dp->dccps_hc_rx_ccid == NULL ||
200 dp->dccps_hc_tx_ccid == NULL)) {
201 ccid_hc_rx_delete(dp->dccps_hc_rx_ccid, sk);
202 ccid_hc_tx_delete(dp->dccps_hc_tx_ccid, sk);
203 if (dmsk->dccpms_send_ack_vector) {
204 dccp_ackvec_free(dp->dccps_hc_rx_ackvec);
205 dp->dccps_hc_rx_ackvec = NULL;
206 }
207 dp->dccps_hc_rx_ccid = dp->dccps_hc_tx_ccid = NULL;
208 return -ENOMEM;
209 }
210 } else {
211 /* control socket doesn't need feat nego */
212 INIT_LIST_HEAD(&dmsk->dccpms_pending);
213 INIT_LIST_HEAD(&dmsk->dccpms_conf);
214 }
215
216 dccp_init_xmit_timers(sk);
217 icsk->icsk_rto = DCCP_TIMEOUT_INIT;
218 icsk->icsk_syn_retries = sysctl_dccp_request_retries;
219 sk->sk_state = DCCP_CLOSED;
220 sk->sk_write_space = dccp_write_space;
221 icsk->icsk_sync_mss = dccp_sync_mss;
222 dp->dccps_mss_cache = 536;
223 dp->dccps_role = DCCP_ROLE_UNDEFINED;
224 dp->dccps_service = DCCP_SERVICE_CODE_IS_ABSENT;
225 dp->dccps_l_ack_ratio = dp->dccps_r_ack_ratio = 1;
226
227 return 0;
228 }
229
230 EXPORT_SYMBOL_GPL(dccp_init_sock);
231
232 int dccp_destroy_sock(struct sock *sk)
233 {
234 struct dccp_sock *dp = dccp_sk(sk);
235 struct dccp_minisock *dmsk = dccp_msk(sk);
236
237 /*
238 * DCCP doesn't use sk_write_queue, just sk_send_head
239 * for retransmissions
240 */
241 if (sk->sk_send_head != NULL) {
242 kfree_skb(sk->sk_send_head);
243 sk->sk_send_head = NULL;
244 }
245
246 /* Clean up a referenced DCCP bind bucket. */
247 if (inet_csk(sk)->icsk_bind_hash != NULL)
248 inet_put_port(&dccp_hashinfo, sk);
249
250 kfree(dp->dccps_service_list);
251 dp->dccps_service_list = NULL;
252
253 if (dmsk->dccpms_send_ack_vector) {
254 dccp_ackvec_free(dp->dccps_hc_rx_ackvec);
255 dp->dccps_hc_rx_ackvec = NULL;
256 }
257 ccid_hc_rx_delete(dp->dccps_hc_rx_ccid, sk);
258 ccid_hc_tx_delete(dp->dccps_hc_tx_ccid, sk);
259 dp->dccps_hc_rx_ccid = dp->dccps_hc_tx_ccid = NULL;
260
261 /* clean up feature negotiation state */
262 dccp_feat_clean(dmsk);
263
264 return 0;
265 }
266
267 EXPORT_SYMBOL_GPL(dccp_destroy_sock);
268
269 static inline int dccp_listen_start(struct sock *sk, int backlog)
270 {
271 struct dccp_sock *dp = dccp_sk(sk);
272
273 dp->dccps_role = DCCP_ROLE_LISTEN;
274 return inet_csk_listen_start(sk, backlog);
275 }
276
277 int dccp_disconnect(struct sock *sk, int flags)
278 {
279 struct inet_connection_sock *icsk = inet_csk(sk);
280 struct inet_sock *inet = inet_sk(sk);
281 int err = 0;
282 const int old_state = sk->sk_state;
283
284 if (old_state != DCCP_CLOSED)
285 dccp_set_state(sk, DCCP_CLOSED);
286
287 /* ABORT function of RFC793 */
288 if (old_state == DCCP_LISTEN) {
289 inet_csk_listen_stop(sk);
290 /* FIXME: do the active reset thing */
291 } else if (old_state == DCCP_REQUESTING)
292 sk->sk_err = ECONNRESET;
293
294 dccp_clear_xmit_timers(sk);
295 __skb_queue_purge(&sk->sk_receive_queue);
296 if (sk->sk_send_head != NULL) {
297 __kfree_skb(sk->sk_send_head);
298 sk->sk_send_head = NULL;
299 }
300
301 inet->dport = 0;
302
303 if (!(sk->sk_userlocks & SOCK_BINDADDR_LOCK))
304 inet_reset_saddr(sk);
305
306 sk->sk_shutdown = 0;
307 sock_reset_flag(sk, SOCK_DONE);
308
309 icsk->icsk_backoff = 0;
310 inet_csk_delack_init(sk);
311 __sk_dst_reset(sk);
312
313 BUG_TRAP(!inet->num || icsk->icsk_bind_hash);
314
315 sk->sk_error_report(sk);
316 return err;
317 }
318
319 EXPORT_SYMBOL_GPL(dccp_disconnect);
320
321 /*
322 * Wait for a DCCP event.
323 *
324 * Note that we don't need to lock the socket, as the upper poll layers
325 * take care of normal races (between the test and the event) and we don't
326 * go look at any of the socket buffers directly.
327 */
328 unsigned int dccp_poll(struct file *file, struct socket *sock,
329 poll_table *wait)
330 {
331 unsigned int mask;
332 struct sock *sk = sock->sk;
333
334 poll_wait(file, sk->sk_sleep, wait);
335 if (sk->sk_state == DCCP_LISTEN)
336 return inet_csk_listen_poll(sk);
337
338 /* Socket is not locked. We are protected from async events
339 by poll logic and correct handling of state changes
340 made by another threads is impossible in any case.
341 */
342
343 mask = 0;
344 if (sk->sk_err)
345 mask = POLLERR;
346
347 if (sk->sk_shutdown == SHUTDOWN_MASK || sk->sk_state == DCCP_CLOSED)
348 mask |= POLLHUP;
349 if (sk->sk_shutdown & RCV_SHUTDOWN)
350 mask |= POLLIN | POLLRDNORM | POLLRDHUP;
351
352 /* Connected? */
353 if ((1 << sk->sk_state) & ~(DCCPF_REQUESTING | DCCPF_RESPOND)) {
354 if (atomic_read(&sk->sk_rmem_alloc) > 0)
355 mask |= POLLIN | POLLRDNORM;
356
357 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
358 if (sk_stream_wspace(sk) >= sk_stream_min_wspace(sk)) {
359 mask |= POLLOUT | POLLWRNORM;
360 } else { /* send SIGIO later */
361 set_bit(SOCK_ASYNC_NOSPACE,
362 &sk->sk_socket->flags);
363 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
364
365 /* Race breaker. If space is freed after
366 * wspace test but before the flags are set,
367 * IO signal will be lost.
368 */
369 if (sk_stream_wspace(sk) >= sk_stream_min_wspace(sk))
370 mask |= POLLOUT | POLLWRNORM;
371 }
372 }
373 }
374 return mask;
375 }
376
377 EXPORT_SYMBOL_GPL(dccp_poll);
378
379 int dccp_ioctl(struct sock *sk, int cmd, unsigned long arg)
380 {
381 dccp_pr_debug("entry\n");
382 return -ENOIOCTLCMD;
383 }
384
385 EXPORT_SYMBOL_GPL(dccp_ioctl);
386
387 static int dccp_setsockopt_service(struct sock *sk, const __be32 service,
388 char __user *optval, int optlen)
389 {
390 struct dccp_sock *dp = dccp_sk(sk);
391 struct dccp_service_list *sl = NULL;
392
393 if (service == DCCP_SERVICE_INVALID_VALUE ||
394 optlen > DCCP_SERVICE_LIST_MAX_LEN * sizeof(u32))
395 return -EINVAL;
396
397 if (optlen > sizeof(service)) {
398 sl = kmalloc(optlen, GFP_KERNEL);
399 if (sl == NULL)
400 return -ENOMEM;
401
402 sl->dccpsl_nr = optlen / sizeof(u32) - 1;
403 if (copy_from_user(sl->dccpsl_list,
404 optval + sizeof(service),
405 optlen - sizeof(service)) ||
406 dccp_list_has_service(sl, DCCP_SERVICE_INVALID_VALUE)) {
407 kfree(sl);
408 return -EFAULT;
409 }
410 }
411
412 lock_sock(sk);
413 dp->dccps_service = service;
414
415 kfree(dp->dccps_service_list);
416
417 dp->dccps_service_list = sl;
418 release_sock(sk);
419 return 0;
420 }
421
422 /* byte 1 is feature. the rest is the preference list */
423 static int dccp_setsockopt_change(struct sock *sk, int type,
424 struct dccp_so_feat __user *optval)
425 {
426 struct dccp_so_feat opt;
427 u8 *val;
428 int rc;
429
430 if (copy_from_user(&opt, optval, sizeof(opt)))
431 return -EFAULT;
432
433 val = kmalloc(opt.dccpsf_len, GFP_KERNEL);
434 if (!val)
435 return -ENOMEM;
436
437 if (copy_from_user(val, opt.dccpsf_val, opt.dccpsf_len)) {
438 rc = -EFAULT;
439 goto out_free_val;
440 }
441
442 rc = dccp_feat_change(dccp_msk(sk), type, opt.dccpsf_feat,
443 val, opt.dccpsf_len, GFP_KERNEL);
444 if (rc)
445 goto out_free_val;
446
447 out:
448 return rc;
449
450 out_free_val:
451 kfree(val);
452 goto out;
453 }
454
455 static int do_dccp_setsockopt(struct sock *sk, int level, int optname,
456 char __user *optval, int optlen)
457 {
458 struct dccp_sock *dp = dccp_sk(sk);
459 int val, err = 0;
460
461 if (optlen < sizeof(int))
462 return -EINVAL;
463
464 if (get_user(val, (int __user *)optval))
465 return -EFAULT;
466
467 if (optname == DCCP_SOCKOPT_SERVICE)
468 return dccp_setsockopt_service(sk, val, optval, optlen);
469
470 lock_sock(sk);
471 switch (optname) {
472 case DCCP_SOCKOPT_PACKET_SIZE:
473 DCCP_WARN("sockopt(PACKET_SIZE) is deprecated: fix your app\n");
474 err = 0;
475 break;
476 case DCCP_SOCKOPT_CHANGE_L:
477 if (optlen != sizeof(struct dccp_so_feat))
478 err = -EINVAL;
479 else
480 err = dccp_setsockopt_change(sk, DCCPO_CHANGE_L,
481 (struct dccp_so_feat __user *)
482 optval);
483 break;
484 case DCCP_SOCKOPT_CHANGE_R:
485 if (optlen != sizeof(struct dccp_so_feat))
486 err = -EINVAL;
487 else
488 err = dccp_setsockopt_change(sk, DCCPO_CHANGE_R,
489 (struct dccp_so_feat __user *)
490 optval);
491 break;
492 case DCCP_SOCKOPT_SEND_CSCOV: /* sender side, RFC 4340, sec. 9.2 */
493 if (val < 0 || val > 15)
494 err = -EINVAL;
495 else
496 dp->dccps_pcslen = val;
497 break;
498 case DCCP_SOCKOPT_RECV_CSCOV: /* receiver side, RFC 4340 sec. 9.2.1 */
499 if (val < 0 || val > 15)
500 err = -EINVAL;
501 else {
502 dp->dccps_pcrlen = val;
503 /* FIXME: add feature negotiation,
504 * ChangeL(MinimumChecksumCoverage, val) */
505 }
506 break;
507 default:
508 err = -ENOPROTOOPT;
509 break;
510 }
511
512 release_sock(sk);
513 return err;
514 }
515
516 int dccp_setsockopt(struct sock *sk, int level, int optname,
517 char __user *optval, int optlen)
518 {
519 if (level != SOL_DCCP)
520 return inet_csk(sk)->icsk_af_ops->setsockopt(sk, level,
521 optname, optval,
522 optlen);
523 return do_dccp_setsockopt(sk, level, optname, optval, optlen);
524 }
525
526 EXPORT_SYMBOL_GPL(dccp_setsockopt);
527
528 #ifdef CONFIG_COMPAT
529 int compat_dccp_setsockopt(struct sock *sk, int level, int optname,
530 char __user *optval, int optlen)
531 {
532 if (level != SOL_DCCP)
533 return inet_csk_compat_setsockopt(sk, level, optname,
534 optval, optlen);
535 return do_dccp_setsockopt(sk, level, optname, optval, optlen);
536 }
537
538 EXPORT_SYMBOL_GPL(compat_dccp_setsockopt);
539 #endif
540
541 static int dccp_getsockopt_service(struct sock *sk, int len,
542 __be32 __user *optval,
543 int __user *optlen)
544 {
545 const struct dccp_sock *dp = dccp_sk(sk);
546 const struct dccp_service_list *sl;
547 int err = -ENOENT, slen = 0, total_len = sizeof(u32);
548
549 lock_sock(sk);
550 if ((sl = dp->dccps_service_list) != NULL) {
551 slen = sl->dccpsl_nr * sizeof(u32);
552 total_len += slen;
553 }
554
555 err = -EINVAL;
556 if (total_len > len)
557 goto out;
558
559 err = 0;
560 if (put_user(total_len, optlen) ||
561 put_user(dp->dccps_service, optval) ||
562 (sl != NULL && copy_to_user(optval + 1, sl->dccpsl_list, slen)))
563 err = -EFAULT;
564 out:
565 release_sock(sk);
566 return err;
567 }
568
569 static int do_dccp_getsockopt(struct sock *sk, int level, int optname,
570 char __user *optval, int __user *optlen)
571 {
572 struct dccp_sock *dp;
573 int val, len;
574
575 if (get_user(len, optlen))
576 return -EFAULT;
577
578 if (len < sizeof(int))
579 return -EINVAL;
580
581 dp = dccp_sk(sk);
582
583 switch (optname) {
584 case DCCP_SOCKOPT_PACKET_SIZE:
585 DCCP_WARN("sockopt(PACKET_SIZE) is deprecated: fix your app\n");
586 return 0;
587 case DCCP_SOCKOPT_SERVICE:
588 return dccp_getsockopt_service(sk, len,
589 (__be32 __user *)optval, optlen);
590 case DCCP_SOCKOPT_SEND_CSCOV:
591 val = dp->dccps_pcslen;
592 break;
593 case DCCP_SOCKOPT_RECV_CSCOV:
594 val = dp->dccps_pcrlen;
595 break;
596 case 128 ... 191:
597 return ccid_hc_rx_getsockopt(dp->dccps_hc_rx_ccid, sk, optname,
598 len, (u32 __user *)optval, optlen);
599 case 192 ... 255:
600 return ccid_hc_tx_getsockopt(dp->dccps_hc_tx_ccid, sk, optname,
601 len, (u32 __user *)optval, optlen);
602 default:
603 return -ENOPROTOOPT;
604 }
605
606 if (put_user(len, optlen) || copy_to_user(optval, &val, len))
607 return -EFAULT;
608
609 return 0;
610 }
611
612 int dccp_getsockopt(struct sock *sk, int level, int optname,
613 char __user *optval, int __user *optlen)
614 {
615 if (level != SOL_DCCP)
616 return inet_csk(sk)->icsk_af_ops->getsockopt(sk, level,
617 optname, optval,
618 optlen);
619 return do_dccp_getsockopt(sk, level, optname, optval, optlen);
620 }
621
622 EXPORT_SYMBOL_GPL(dccp_getsockopt);
623
624 #ifdef CONFIG_COMPAT
625 int compat_dccp_getsockopt(struct sock *sk, int level, int optname,
626 char __user *optval, int __user *optlen)
627 {
628 if (level != SOL_DCCP)
629 return inet_csk_compat_getsockopt(sk, level, optname,
630 optval, optlen);
631 return do_dccp_getsockopt(sk, level, optname, optval, optlen);
632 }
633
634 EXPORT_SYMBOL_GPL(compat_dccp_getsockopt);
635 #endif
636
637 int dccp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
638 size_t len)
639 {
640 const struct dccp_sock *dp = dccp_sk(sk);
641 const int flags = msg->msg_flags;
642 const int noblock = flags & MSG_DONTWAIT;
643 struct sk_buff *skb;
644 int rc, size;
645 long timeo;
646
647 if (len > dp->dccps_mss_cache)
648 return -EMSGSIZE;
649
650 lock_sock(sk);
651
652 if (sysctl_dccp_tx_qlen &&
653 (sk->sk_write_queue.qlen >= sysctl_dccp_tx_qlen)) {
654 rc = -EAGAIN;
655 goto out_release;
656 }
657
658 timeo = sock_sndtimeo(sk, noblock);
659
660 /*
661 * We have to use sk_stream_wait_connect here to set sk_write_pending,
662 * so that the trick in dccp_rcv_request_sent_state_process.
663 */
664 /* Wait for a connection to finish. */
665 if ((1 << sk->sk_state) & ~(DCCPF_OPEN | DCCPF_PARTOPEN | DCCPF_CLOSING))
666 if ((rc = sk_stream_wait_connect(sk, &timeo)) != 0)
667 goto out_release;
668
669 size = sk->sk_prot->max_header + len;
670 release_sock(sk);
671 skb = sock_alloc_send_skb(sk, size, noblock, &rc);
672 lock_sock(sk);
673 if (skb == NULL)
674 goto out_release;
675
676 skb_reserve(skb, sk->sk_prot->max_header);
677 rc = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
678 if (rc != 0)
679 goto out_discard;
680
681 skb_queue_tail(&sk->sk_write_queue, skb);
682 dccp_write_xmit(sk,0);
683 out_release:
684 release_sock(sk);
685 return rc ? : len;
686 out_discard:
687 kfree_skb(skb);
688 goto out_release;
689 }
690
691 EXPORT_SYMBOL_GPL(dccp_sendmsg);
692
693 int dccp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
694 size_t len, int nonblock, int flags, int *addr_len)
695 {
696 const struct dccp_hdr *dh;
697 long timeo;
698
699 lock_sock(sk);
700
701 if (sk->sk_state == DCCP_LISTEN) {
702 len = -ENOTCONN;
703 goto out;
704 }
705
706 timeo = sock_rcvtimeo(sk, nonblock);
707
708 do {
709 struct sk_buff *skb = skb_peek(&sk->sk_receive_queue);
710
711 if (skb == NULL)
712 goto verify_sock_status;
713
714 dh = dccp_hdr(skb);
715
716 if (dh->dccph_type == DCCP_PKT_DATA ||
717 dh->dccph_type == DCCP_PKT_DATAACK)
718 goto found_ok_skb;
719
720 if (dh->dccph_type == DCCP_PKT_RESET ||
721 dh->dccph_type == DCCP_PKT_CLOSE) {
722 dccp_pr_debug("found fin ok!\n");
723 len = 0;
724 goto found_fin_ok;
725 }
726 dccp_pr_debug("packet_type=%s\n",
727 dccp_packet_name(dh->dccph_type));
728 sk_eat_skb(sk, skb, 0);
729 verify_sock_status:
730 if (sock_flag(sk, SOCK_DONE)) {
731 len = 0;
732 break;
733 }
734
735 if (sk->sk_err) {
736 len = sock_error(sk);
737 break;
738 }
739
740 if (sk->sk_shutdown & RCV_SHUTDOWN) {
741 len = 0;
742 break;
743 }
744
745 if (sk->sk_state == DCCP_CLOSED) {
746 if (!sock_flag(sk, SOCK_DONE)) {
747 /* This occurs when user tries to read
748 * from never connected socket.
749 */
750 len = -ENOTCONN;
751 break;
752 }
753 len = 0;
754 break;
755 }
756
757 if (!timeo) {
758 len = -EAGAIN;
759 break;
760 }
761
762 if (signal_pending(current)) {
763 len = sock_intr_errno(timeo);
764 break;
765 }
766
767 sk_wait_data(sk, &timeo);
768 continue;
769 found_ok_skb:
770 if (len > skb->len)
771 len = skb->len;
772 else if (len < skb->len)
773 msg->msg_flags |= MSG_TRUNC;
774
775 if (skb_copy_datagram_iovec(skb, 0, msg->msg_iov, len)) {
776 /* Exception. Bailout! */
777 len = -EFAULT;
778 break;
779 }
780 found_fin_ok:
781 if (!(flags & MSG_PEEK))
782 sk_eat_skb(sk, skb, 0);
783 break;
784 } while (1);
785 out:
786 release_sock(sk);
787 return len;
788 }
789
790 EXPORT_SYMBOL_GPL(dccp_recvmsg);
791
792 int inet_dccp_listen(struct socket *sock, int backlog)
793 {
794 struct sock *sk = sock->sk;
795 unsigned char old_state;
796 int err;
797
798 lock_sock(sk);
799
800 err = -EINVAL;
801 if (sock->state != SS_UNCONNECTED || sock->type != SOCK_DCCP)
802 goto out;
803
804 old_state = sk->sk_state;
805 if (!((1 << old_state) & (DCCPF_CLOSED | DCCPF_LISTEN)))
806 goto out;
807
808 /* Really, if the socket is already in listen state
809 * we can only allow the backlog to be adjusted.
810 */
811 if (old_state != DCCP_LISTEN) {
812 /*
813 * FIXME: here it probably should be sk->sk_prot->listen_start
814 * see tcp_listen_start
815 */
816 err = dccp_listen_start(sk, backlog);
817 if (err)
818 goto out;
819 }
820 sk->sk_max_ack_backlog = backlog;
821 err = 0;
822
823 out:
824 release_sock(sk);
825 return err;
826 }
827
828 EXPORT_SYMBOL_GPL(inet_dccp_listen);
829
830 static const unsigned char dccp_new_state[] = {
831 /* current state: new state: action: */
832 [0] = DCCP_CLOSED,
833 [DCCP_OPEN] = DCCP_CLOSING | DCCP_ACTION_FIN,
834 [DCCP_REQUESTING] = DCCP_CLOSED,
835 [DCCP_PARTOPEN] = DCCP_CLOSING | DCCP_ACTION_FIN,
836 [DCCP_LISTEN] = DCCP_CLOSED,
837 [DCCP_RESPOND] = DCCP_CLOSED,
838 [DCCP_CLOSING] = DCCP_CLOSED,
839 [DCCP_TIME_WAIT] = DCCP_CLOSED,
840 [DCCP_CLOSED] = DCCP_CLOSED,
841 };
842
843 static int dccp_close_state(struct sock *sk)
844 {
845 const int next = dccp_new_state[sk->sk_state];
846 const int ns = next & DCCP_STATE_MASK;
847
848 if (ns != sk->sk_state)
849 dccp_set_state(sk, ns);
850
851 return next & DCCP_ACTION_FIN;
852 }
853
854 void dccp_close(struct sock *sk, long timeout)
855 {
856 struct dccp_sock *dp = dccp_sk(sk);
857 struct sk_buff *skb;
858 int state;
859
860 lock_sock(sk);
861
862 sk->sk_shutdown = SHUTDOWN_MASK;
863
864 if (sk->sk_state == DCCP_LISTEN) {
865 dccp_set_state(sk, DCCP_CLOSED);
866
867 /* Special case. */
868 inet_csk_listen_stop(sk);
869
870 goto adjudge_to_death;
871 }
872
873 sk_stop_timer(sk, &dp->dccps_xmit_timer);
874
875 /*
876 * We need to flush the recv. buffs. We do this only on the
877 * descriptor close, not protocol-sourced closes, because the
878 *reader process may not have drained the data yet!
879 */
880 /* FIXME: check for unread data */
881 while ((skb = __skb_dequeue(&sk->sk_receive_queue)) != NULL) {
882 __kfree_skb(skb);
883 }
884
885 if (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime) {
886 /* Check zero linger _after_ checking for unread data. */
887 sk->sk_prot->disconnect(sk, 0);
888 } else if (dccp_close_state(sk)) {
889 dccp_send_close(sk, 1);
890 }
891
892 sk_stream_wait_close(sk, timeout);
893
894 adjudge_to_death:
895 state = sk->sk_state;
896 sock_hold(sk);
897 sock_orphan(sk);
898 atomic_inc(sk->sk_prot->orphan_count);
899
900 /*
901 * It is the last release_sock in its life. It will remove backlog.
902 */
903 release_sock(sk);
904 /*
905 * Now socket is owned by kernel and we acquire BH lock
906 * to finish close. No need to check for user refs.
907 */
908 local_bh_disable();
909 bh_lock_sock(sk);
910 BUG_TRAP(!sock_owned_by_user(sk));
911
912 /* Have we already been destroyed by a softirq or backlog? */
913 if (state != DCCP_CLOSED && sk->sk_state == DCCP_CLOSED)
914 goto out;
915
916 /*
917 * The last release_sock may have processed the CLOSE or RESET
918 * packet moving sock to CLOSED state, if not we have to fire
919 * the CLOSE/CLOSEREQ retransmission timer, see "8.3. Termination"
920 * in draft-ietf-dccp-spec-11. -acme
921 */
922 if (sk->sk_state == DCCP_CLOSING) {
923 /* FIXME: should start at 2 * RTT */
924 /* Timer for repeating the CLOSE/CLOSEREQ until an answer. */
925 inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
926 inet_csk(sk)->icsk_rto,
927 DCCP_RTO_MAX);
928 #if 0
929 /* Yeah, we should use sk->sk_prot->orphan_count, etc */
930 dccp_set_state(sk, DCCP_CLOSED);
931 #endif
932 }
933
934 if (sk->sk_state == DCCP_CLOSED)
935 inet_csk_destroy_sock(sk);
936
937 /* Otherwise, socket is reprieved until protocol close. */
938
939 out:
940 bh_unlock_sock(sk);
941 local_bh_enable();
942 sock_put(sk);
943 }
944
945 EXPORT_SYMBOL_GPL(dccp_close);
946
947 void dccp_shutdown(struct sock *sk, int how)
948 {
949 dccp_pr_debug("entry\n");
950 }
951
952 EXPORT_SYMBOL_GPL(dccp_shutdown);
953
954 static int __init dccp_mib_init(void)
955 {
956 int rc = -ENOMEM;
957
958 dccp_statistics[0] = alloc_percpu(struct dccp_mib);
959 if (dccp_statistics[0] == NULL)
960 goto out;
961
962 dccp_statistics[1] = alloc_percpu(struct dccp_mib);
963 if (dccp_statistics[1] == NULL)
964 goto out_free_one;
965
966 rc = 0;
967 out:
968 return rc;
969 out_free_one:
970 free_percpu(dccp_statistics[0]);
971 dccp_statistics[0] = NULL;
972 goto out;
973
974 }
975
976 static void dccp_mib_exit(void)
977 {
978 free_percpu(dccp_statistics[0]);
979 free_percpu(dccp_statistics[1]);
980 dccp_statistics[0] = dccp_statistics[1] = NULL;
981 }
982
983 static int thash_entries;
984 module_param(thash_entries, int, 0444);
985 MODULE_PARM_DESC(thash_entries, "Number of ehash buckets");
986
987 #ifdef CONFIG_IP_DCCP_DEBUG
988 int dccp_debug;
989 module_param(dccp_debug, int, 0444);
990 MODULE_PARM_DESC(dccp_debug, "Enable debug messages");
991
992 EXPORT_SYMBOL_GPL(dccp_debug);
993 #endif
994
995 static int __init dccp_init(void)
996 {
997 unsigned long goal;
998 int ehash_order, bhash_order, i;
999 int rc = -ENOBUFS;
1000
1001 dccp_hashinfo.bind_bucket_cachep =
1002 kmem_cache_create("dccp_bind_bucket",
1003 sizeof(struct inet_bind_bucket), 0,
1004 SLAB_HWCACHE_ALIGN, NULL, NULL);
1005 if (!dccp_hashinfo.bind_bucket_cachep)
1006 goto out;
1007
1008 /*
1009 * Size and allocate the main established and bind bucket
1010 * hash tables.
1011 *
1012 * The methodology is similar to that of the buffer cache.
1013 */
1014 if (num_physpages >= (128 * 1024))
1015 goal = num_physpages >> (21 - PAGE_SHIFT);
1016 else
1017 goal = num_physpages >> (23 - PAGE_SHIFT);
1018
1019 if (thash_entries)
1020 goal = (thash_entries *
1021 sizeof(struct inet_ehash_bucket)) >> PAGE_SHIFT;
1022 for (ehash_order = 0; (1UL << ehash_order) < goal; ehash_order++)
1023 ;
1024 do {
1025 dccp_hashinfo.ehash_size = (1UL << ehash_order) * PAGE_SIZE /
1026 sizeof(struct inet_ehash_bucket);
1027 dccp_hashinfo.ehash_size >>= 1;
1028 while (dccp_hashinfo.ehash_size &
1029 (dccp_hashinfo.ehash_size - 1))
1030 dccp_hashinfo.ehash_size--;
1031 dccp_hashinfo.ehash = (struct inet_ehash_bucket *)
1032 __get_free_pages(GFP_ATOMIC, ehash_order);
1033 } while (!dccp_hashinfo.ehash && --ehash_order > 0);
1034
1035 if (!dccp_hashinfo.ehash) {
1036 DCCP_CRIT("Failed to allocate DCCP established hash table");
1037 goto out_free_bind_bucket_cachep;
1038 }
1039
1040 for (i = 0; i < (dccp_hashinfo.ehash_size << 1); i++) {
1041 rwlock_init(&dccp_hashinfo.ehash[i].lock);
1042 INIT_HLIST_HEAD(&dccp_hashinfo.ehash[i].chain);
1043 }
1044
1045 bhash_order = ehash_order;
1046
1047 do {
1048 dccp_hashinfo.bhash_size = (1UL << bhash_order) * PAGE_SIZE /
1049 sizeof(struct inet_bind_hashbucket);
1050 if ((dccp_hashinfo.bhash_size > (64 * 1024)) &&
1051 bhash_order > 0)
1052 continue;
1053 dccp_hashinfo.bhash = (struct inet_bind_hashbucket *)
1054 __get_free_pages(GFP_ATOMIC, bhash_order);
1055 } while (!dccp_hashinfo.bhash && --bhash_order >= 0);
1056
1057 if (!dccp_hashinfo.bhash) {
1058 DCCP_CRIT("Failed to allocate DCCP bind hash table");
1059 goto out_free_dccp_ehash;
1060 }
1061
1062 for (i = 0; i < dccp_hashinfo.bhash_size; i++) {
1063 spin_lock_init(&dccp_hashinfo.bhash[i].lock);
1064 INIT_HLIST_HEAD(&dccp_hashinfo.bhash[i].chain);
1065 }
1066
1067 rc = dccp_mib_init();
1068 if (rc)
1069 goto out_free_dccp_bhash;
1070
1071 rc = dccp_ackvec_init();
1072 if (rc)
1073 goto out_free_dccp_mib;
1074
1075 rc = dccp_sysctl_init();
1076 if (rc)
1077 goto out_ackvec_exit;
1078 out:
1079 return rc;
1080 out_ackvec_exit:
1081 dccp_ackvec_exit();
1082 out_free_dccp_mib:
1083 dccp_mib_exit();
1084 out_free_dccp_bhash:
1085 free_pages((unsigned long)dccp_hashinfo.bhash, bhash_order);
1086 dccp_hashinfo.bhash = NULL;
1087 out_free_dccp_ehash:
1088 free_pages((unsigned long)dccp_hashinfo.ehash, ehash_order);
1089 dccp_hashinfo.ehash = NULL;
1090 out_free_bind_bucket_cachep:
1091 kmem_cache_destroy(dccp_hashinfo.bind_bucket_cachep);
1092 dccp_hashinfo.bind_bucket_cachep = NULL;
1093 goto out;
1094 }
1095
1096 static void __exit dccp_fini(void)
1097 {
1098 dccp_mib_exit();
1099 free_pages((unsigned long)dccp_hashinfo.bhash,
1100 get_order(dccp_hashinfo.bhash_size *
1101 sizeof(struct inet_bind_hashbucket)));
1102 free_pages((unsigned long)dccp_hashinfo.ehash,
1103 get_order(dccp_hashinfo.ehash_size *
1104 sizeof(struct inet_ehash_bucket)));
1105 kmem_cache_destroy(dccp_hashinfo.bind_bucket_cachep);
1106 dccp_ackvec_exit();
1107 dccp_sysctl_exit();
1108 }
1109
1110 module_init(dccp_init);
1111 module_exit(dccp_fini);
1112
1113 MODULE_LICENSE("GPL");
1114 MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@conectiva.com.br>");
1115 MODULE_DESCRIPTION("DCCP - Datagram Congestion Controlled Protocol");
linux v2.6.22.y-op