net: Remove unnecessary inclusions of asm/semaphore.h
[linux-2.6/mini2440.git] / net / dccp / proto.c
blob9dfe2470962c7dd966f93243cdefb29b377f914e
1 /*
2 * net/dccp/proto.c
4 * An implementation of the DCCP protocol
5 * Arnaldo Carvalho de Melo <acme@conectiva.com.br>
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.
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>
25 #include <net/inet_sock.h>
26 #include <net/sock.h>
27 #include <net/xfrm.h>
29 #include <asm/ioctls.h>
30 #include <linux/spinlock.h>
31 #include <linux/timer.h>
32 #include <linux/delay.h>
33 #include <linux/poll.h>
35 #include "ccid.h"
36 #include "dccp.h"
37 #include "feat.h"
39 DEFINE_SNMP_STAT(struct dccp_mib, dccp_statistics) __read_mostly;
41 EXPORT_SYMBOL_GPL(dccp_statistics);
43 atomic_t dccp_orphan_count = ATOMIC_INIT(0);
45 EXPORT_SYMBOL_GPL(dccp_orphan_count);
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),
53 EXPORT_SYMBOL_GPL(dccp_hashinfo);
55 /* the maximum queue length for tx in packets. 0 is no limit */
56 int sysctl_dccp_tx_qlen __read_mostly = 5;
58 void dccp_set_state(struct sock *sk, const int state)
60 const int oldstate = sk->sk_state;
62 dccp_pr_debug("%s(%p) %s --> %s\n", dccp_role(sk), sk,
63 dccp_state_name(oldstate), dccp_state_name(state));
64 WARN_ON(state == oldstate);
66 switch (state) {
67 case DCCP_OPEN:
68 if (oldstate != DCCP_OPEN)
69 DCCP_INC_STATS(DCCP_MIB_CURRESTAB);
70 break;
72 case DCCP_CLOSED:
73 if (oldstate == DCCP_OPEN || oldstate == DCCP_ACTIVE_CLOSEREQ ||
74 oldstate == DCCP_CLOSING)
75 DCCP_INC_STATS(DCCP_MIB_ESTABRESETS);
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(sk);
81 /* fall through */
82 default:
83 if (oldstate == DCCP_OPEN)
84 DCCP_DEC_STATS(DCCP_MIB_CURRESTAB);
87 /* Change state AFTER socket is unhashed to avoid closed
88 * socket sitting in hash tables.
90 sk->sk_state = state;
93 EXPORT_SYMBOL_GPL(dccp_set_state);
95 static void dccp_finish_passive_close(struct sock *sk)
97 switch (sk->sk_state) {
98 case DCCP_PASSIVE_CLOSE:
99 /* Node (client or server) has received Close packet. */
100 dccp_send_reset(sk, DCCP_RESET_CODE_CLOSED);
101 dccp_set_state(sk, DCCP_CLOSED);
102 break;
103 case DCCP_PASSIVE_CLOSEREQ:
105 * Client received CloseReq. We set the `active' flag so that
106 * dccp_send_close() retransmits the Close as per RFC 4340, 8.3.
108 dccp_send_close(sk, 1);
109 dccp_set_state(sk, DCCP_CLOSING);
113 void dccp_done(struct sock *sk)
115 dccp_set_state(sk, DCCP_CLOSED);
116 dccp_clear_xmit_timers(sk);
118 sk->sk_shutdown = SHUTDOWN_MASK;
120 if (!sock_flag(sk, SOCK_DEAD))
121 sk->sk_state_change(sk);
122 else
123 inet_csk_destroy_sock(sk);
126 EXPORT_SYMBOL_GPL(dccp_done);
128 const char *dccp_packet_name(const int type)
130 static const char *dccp_packet_names[] = {
131 [DCCP_PKT_REQUEST] = "REQUEST",
132 [DCCP_PKT_RESPONSE] = "RESPONSE",
133 [DCCP_PKT_DATA] = "DATA",
134 [DCCP_PKT_ACK] = "ACK",
135 [DCCP_PKT_DATAACK] = "DATAACK",
136 [DCCP_PKT_CLOSEREQ] = "CLOSEREQ",
137 [DCCP_PKT_CLOSE] = "CLOSE",
138 [DCCP_PKT_RESET] = "RESET",
139 [DCCP_PKT_SYNC] = "SYNC",
140 [DCCP_PKT_SYNCACK] = "SYNCACK",
143 if (type >= DCCP_NR_PKT_TYPES)
144 return "INVALID";
145 else
146 return dccp_packet_names[type];
149 EXPORT_SYMBOL_GPL(dccp_packet_name);
151 const char *dccp_state_name(const int state)
153 static char *dccp_state_names[] = {
154 [DCCP_OPEN] = "OPEN",
155 [DCCP_REQUESTING] = "REQUESTING",
156 [DCCP_PARTOPEN] = "PARTOPEN",
157 [DCCP_LISTEN] = "LISTEN",
158 [DCCP_RESPOND] = "RESPOND",
159 [DCCP_CLOSING] = "CLOSING",
160 [DCCP_ACTIVE_CLOSEREQ] = "CLOSEREQ",
161 [DCCP_PASSIVE_CLOSE] = "PASSIVE_CLOSE",
162 [DCCP_PASSIVE_CLOSEREQ] = "PASSIVE_CLOSEREQ",
163 [DCCP_TIME_WAIT] = "TIME_WAIT",
164 [DCCP_CLOSED] = "CLOSED",
167 if (state >= DCCP_MAX_STATES)
168 return "INVALID STATE!";
169 else
170 return dccp_state_names[state];
173 EXPORT_SYMBOL_GPL(dccp_state_name);
175 int dccp_init_sock(struct sock *sk, const __u8 ctl_sock_initialized)
177 struct dccp_sock *dp = dccp_sk(sk);
178 struct dccp_minisock *dmsk = dccp_msk(sk);
179 struct inet_connection_sock *icsk = inet_csk(sk);
181 dccp_minisock_init(&dp->dccps_minisock);
183 icsk->icsk_rto = DCCP_TIMEOUT_INIT;
184 icsk->icsk_syn_retries = sysctl_dccp_request_retries;
185 sk->sk_state = DCCP_CLOSED;
186 sk->sk_write_space = dccp_write_space;
187 icsk->icsk_sync_mss = dccp_sync_mss;
188 dp->dccps_mss_cache = 536;
189 dp->dccps_rate_last = jiffies;
190 dp->dccps_role = DCCP_ROLE_UNDEFINED;
191 dp->dccps_service = DCCP_SERVICE_CODE_IS_ABSENT;
192 dp->dccps_l_ack_ratio = dp->dccps_r_ack_ratio = 1;
194 dccp_init_xmit_timers(sk);
197 * FIXME: We're hardcoding the CCID, and doing this at this point makes
198 * the listening (master) sock get CCID control blocks, which is not
199 * necessary, but for now, to not mess with the test userspace apps,
200 * lets leave it here, later the real solution is to do this in a
201 * setsockopt(CCIDs-I-want/accept). -acme
203 if (likely(ctl_sock_initialized)) {
204 int rc = dccp_feat_init(dmsk);
206 if (rc)
207 return rc;
209 if (dmsk->dccpms_send_ack_vector) {
210 dp->dccps_hc_rx_ackvec = dccp_ackvec_alloc(GFP_KERNEL);
211 if (dp->dccps_hc_rx_ackvec == NULL)
212 return -ENOMEM;
214 dp->dccps_hc_rx_ccid = ccid_hc_rx_new(dmsk->dccpms_rx_ccid,
215 sk, GFP_KERNEL);
216 dp->dccps_hc_tx_ccid = ccid_hc_tx_new(dmsk->dccpms_tx_ccid,
217 sk, GFP_KERNEL);
218 if (unlikely(dp->dccps_hc_rx_ccid == NULL ||
219 dp->dccps_hc_tx_ccid == NULL)) {
220 ccid_hc_rx_delete(dp->dccps_hc_rx_ccid, sk);
221 ccid_hc_tx_delete(dp->dccps_hc_tx_ccid, sk);
222 if (dmsk->dccpms_send_ack_vector) {
223 dccp_ackvec_free(dp->dccps_hc_rx_ackvec);
224 dp->dccps_hc_rx_ackvec = NULL;
226 dp->dccps_hc_rx_ccid = dp->dccps_hc_tx_ccid = NULL;
227 return -ENOMEM;
229 } else {
230 /* control socket doesn't need feat nego */
231 INIT_LIST_HEAD(&dmsk->dccpms_pending);
232 INIT_LIST_HEAD(&dmsk->dccpms_conf);
235 return 0;
238 EXPORT_SYMBOL_GPL(dccp_init_sock);
240 int dccp_destroy_sock(struct sock *sk)
242 struct dccp_sock *dp = dccp_sk(sk);
243 struct dccp_minisock *dmsk = dccp_msk(sk);
246 * DCCP doesn't use sk_write_queue, just sk_send_head
247 * for retransmissions
249 if (sk->sk_send_head != NULL) {
250 kfree_skb(sk->sk_send_head);
251 sk->sk_send_head = NULL;
254 /* Clean up a referenced DCCP bind bucket. */
255 if (inet_csk(sk)->icsk_bind_hash != NULL)
256 inet_put_port(sk);
258 kfree(dp->dccps_service_list);
259 dp->dccps_service_list = NULL;
261 if (dmsk->dccpms_send_ack_vector) {
262 dccp_ackvec_free(dp->dccps_hc_rx_ackvec);
263 dp->dccps_hc_rx_ackvec = NULL;
265 ccid_hc_rx_delete(dp->dccps_hc_rx_ccid, sk);
266 ccid_hc_tx_delete(dp->dccps_hc_tx_ccid, sk);
267 dp->dccps_hc_rx_ccid = dp->dccps_hc_tx_ccid = NULL;
269 /* clean up feature negotiation state */
270 dccp_feat_clean(dmsk);
272 return 0;
275 EXPORT_SYMBOL_GPL(dccp_destroy_sock);
277 static inline int dccp_listen_start(struct sock *sk, int backlog)
279 struct dccp_sock *dp = dccp_sk(sk);
281 dp->dccps_role = DCCP_ROLE_LISTEN;
282 return inet_csk_listen_start(sk, backlog);
285 static inline int dccp_need_reset(int state)
287 return state != DCCP_CLOSED && state != DCCP_LISTEN &&
288 state != DCCP_REQUESTING;
291 int dccp_disconnect(struct sock *sk, int flags)
293 struct inet_connection_sock *icsk = inet_csk(sk);
294 struct inet_sock *inet = inet_sk(sk);
295 int err = 0;
296 const int old_state = sk->sk_state;
298 if (old_state != DCCP_CLOSED)
299 dccp_set_state(sk, DCCP_CLOSED);
302 * This corresponds to the ABORT function of RFC793, sec. 3.8
303 * TCP uses a RST segment, DCCP a Reset packet with Code 2, "Aborted".
305 if (old_state == DCCP_LISTEN) {
306 inet_csk_listen_stop(sk);
307 } else if (dccp_need_reset(old_state)) {
308 dccp_send_reset(sk, DCCP_RESET_CODE_ABORTED);
309 sk->sk_err = ECONNRESET;
310 } else if (old_state == DCCP_REQUESTING)
311 sk->sk_err = ECONNRESET;
313 dccp_clear_xmit_timers(sk);
314 __skb_queue_purge(&sk->sk_receive_queue);
315 if (sk->sk_send_head != NULL) {
316 __kfree_skb(sk->sk_send_head);
317 sk->sk_send_head = NULL;
320 inet->dport = 0;
322 if (!(sk->sk_userlocks & SOCK_BINDADDR_LOCK))
323 inet_reset_saddr(sk);
325 sk->sk_shutdown = 0;
326 sock_reset_flag(sk, SOCK_DONE);
328 icsk->icsk_backoff = 0;
329 inet_csk_delack_init(sk);
330 __sk_dst_reset(sk);
332 BUG_TRAP(!inet->num || icsk->icsk_bind_hash);
334 sk->sk_error_report(sk);
335 return err;
338 EXPORT_SYMBOL_GPL(dccp_disconnect);
341 * Wait for a DCCP event.
343 * Note that we don't need to lock the socket, as the upper poll layers
344 * take care of normal races (between the test and the event) and we don't
345 * go look at any of the socket buffers directly.
347 unsigned int dccp_poll(struct file *file, struct socket *sock,
348 poll_table *wait)
350 unsigned int mask;
351 struct sock *sk = sock->sk;
353 poll_wait(file, sk->sk_sleep, wait);
354 if (sk->sk_state == DCCP_LISTEN)
355 return inet_csk_listen_poll(sk);
357 /* Socket is not locked. We are protected from async events
358 by poll logic and correct handling of state changes
359 made by another threads is impossible in any case.
362 mask = 0;
363 if (sk->sk_err)
364 mask = POLLERR;
366 if (sk->sk_shutdown == SHUTDOWN_MASK || sk->sk_state == DCCP_CLOSED)
367 mask |= POLLHUP;
368 if (sk->sk_shutdown & RCV_SHUTDOWN)
369 mask |= POLLIN | POLLRDNORM | POLLRDHUP;
371 /* Connected? */
372 if ((1 << sk->sk_state) & ~(DCCPF_REQUESTING | DCCPF_RESPOND)) {
373 if (atomic_read(&sk->sk_rmem_alloc) > 0)
374 mask |= POLLIN | POLLRDNORM;
376 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
377 if (sk_stream_wspace(sk) >= sk_stream_min_wspace(sk)) {
378 mask |= POLLOUT | POLLWRNORM;
379 } else { /* send SIGIO later */
380 set_bit(SOCK_ASYNC_NOSPACE,
381 &sk->sk_socket->flags);
382 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
384 /* Race breaker. If space is freed after
385 * wspace test but before the flags are set,
386 * IO signal will be lost.
388 if (sk_stream_wspace(sk) >= sk_stream_min_wspace(sk))
389 mask |= POLLOUT | POLLWRNORM;
393 return mask;
396 EXPORT_SYMBOL_GPL(dccp_poll);
398 int dccp_ioctl(struct sock *sk, int cmd, unsigned long arg)
400 int rc = -ENOTCONN;
402 lock_sock(sk);
404 if (sk->sk_state == DCCP_LISTEN)
405 goto out;
407 switch (cmd) {
408 case SIOCINQ: {
409 struct sk_buff *skb;
410 unsigned long amount = 0;
412 skb = skb_peek(&sk->sk_receive_queue);
413 if (skb != NULL) {
415 * We will only return the amount of this packet since
416 * that is all that will be read.
418 amount = skb->len;
420 rc = put_user(amount, (int __user *)arg);
422 break;
423 default:
424 rc = -ENOIOCTLCMD;
425 break;
427 out:
428 release_sock(sk);
429 return rc;
432 EXPORT_SYMBOL_GPL(dccp_ioctl);
434 static int dccp_setsockopt_service(struct sock *sk, const __be32 service,
435 char __user *optval, int optlen)
437 struct dccp_sock *dp = dccp_sk(sk);
438 struct dccp_service_list *sl = NULL;
440 if (service == DCCP_SERVICE_INVALID_VALUE ||
441 optlen > DCCP_SERVICE_LIST_MAX_LEN * sizeof(u32))
442 return -EINVAL;
444 if (optlen > sizeof(service)) {
445 sl = kmalloc(optlen, GFP_KERNEL);
446 if (sl == NULL)
447 return -ENOMEM;
449 sl->dccpsl_nr = optlen / sizeof(u32) - 1;
450 if (copy_from_user(sl->dccpsl_list,
451 optval + sizeof(service),
452 optlen - sizeof(service)) ||
453 dccp_list_has_service(sl, DCCP_SERVICE_INVALID_VALUE)) {
454 kfree(sl);
455 return -EFAULT;
459 lock_sock(sk);
460 dp->dccps_service = service;
462 kfree(dp->dccps_service_list);
464 dp->dccps_service_list = sl;
465 release_sock(sk);
466 return 0;
469 /* byte 1 is feature. the rest is the preference list */
470 static int dccp_setsockopt_change(struct sock *sk, int type,
471 struct dccp_so_feat __user *optval)
473 struct dccp_so_feat opt;
474 u8 *val;
475 int rc;
477 if (copy_from_user(&opt, optval, sizeof(opt)))
478 return -EFAULT;
480 val = kmalloc(opt.dccpsf_len, GFP_KERNEL);
481 if (!val)
482 return -ENOMEM;
484 if (copy_from_user(val, opt.dccpsf_val, opt.dccpsf_len)) {
485 rc = -EFAULT;
486 goto out_free_val;
489 rc = dccp_feat_change(dccp_msk(sk), type, opt.dccpsf_feat,
490 val, opt.dccpsf_len, GFP_KERNEL);
491 if (rc)
492 goto out_free_val;
494 out:
495 return rc;
497 out_free_val:
498 kfree(val);
499 goto out;
502 static int do_dccp_setsockopt(struct sock *sk, int level, int optname,
503 char __user *optval, int optlen)
505 struct dccp_sock *dp = dccp_sk(sk);
506 int val, err = 0;
508 if (optlen < sizeof(int))
509 return -EINVAL;
511 if (get_user(val, (int __user *)optval))
512 return -EFAULT;
514 if (optname == DCCP_SOCKOPT_SERVICE)
515 return dccp_setsockopt_service(sk, val, optval, optlen);
517 lock_sock(sk);
518 switch (optname) {
519 case DCCP_SOCKOPT_PACKET_SIZE:
520 DCCP_WARN("sockopt(PACKET_SIZE) is deprecated: fix your app\n");
521 err = 0;
522 break;
523 case DCCP_SOCKOPT_CHANGE_L:
524 if (optlen != sizeof(struct dccp_so_feat))
525 err = -EINVAL;
526 else
527 err = dccp_setsockopt_change(sk, DCCPO_CHANGE_L,
528 (struct dccp_so_feat __user *)
529 optval);
530 break;
531 case DCCP_SOCKOPT_CHANGE_R:
532 if (optlen != sizeof(struct dccp_so_feat))
533 err = -EINVAL;
534 else
535 err = dccp_setsockopt_change(sk, DCCPO_CHANGE_R,
536 (struct dccp_so_feat __user *)
537 optval);
538 break;
539 case DCCP_SOCKOPT_SERVER_TIMEWAIT:
540 if (dp->dccps_role != DCCP_ROLE_SERVER)
541 err = -EOPNOTSUPP;
542 else
543 dp->dccps_server_timewait = (val != 0);
544 break;
545 case DCCP_SOCKOPT_SEND_CSCOV: /* sender side, RFC 4340, sec. 9.2 */
546 if (val < 0 || val > 15)
547 err = -EINVAL;
548 else
549 dp->dccps_pcslen = val;
550 break;
551 case DCCP_SOCKOPT_RECV_CSCOV: /* receiver side, RFC 4340 sec. 9.2.1 */
552 if (val < 0 || val > 15)
553 err = -EINVAL;
554 else {
555 dp->dccps_pcrlen = val;
556 /* FIXME: add feature negotiation,
557 * ChangeL(MinimumChecksumCoverage, val) */
559 break;
560 default:
561 err = -ENOPROTOOPT;
562 break;
565 release_sock(sk);
566 return err;
569 int dccp_setsockopt(struct sock *sk, int level, int optname,
570 char __user *optval, int optlen)
572 if (level != SOL_DCCP)
573 return inet_csk(sk)->icsk_af_ops->setsockopt(sk, level,
574 optname, optval,
575 optlen);
576 return do_dccp_setsockopt(sk, level, optname, optval, optlen);
579 EXPORT_SYMBOL_GPL(dccp_setsockopt);
581 #ifdef CONFIG_COMPAT
582 int compat_dccp_setsockopt(struct sock *sk, int level, int optname,
583 char __user *optval, int optlen)
585 if (level != SOL_DCCP)
586 return inet_csk_compat_setsockopt(sk, level, optname,
587 optval, optlen);
588 return do_dccp_setsockopt(sk, level, optname, optval, optlen);
591 EXPORT_SYMBOL_GPL(compat_dccp_setsockopt);
592 #endif
594 static int dccp_getsockopt_service(struct sock *sk, int len,
595 __be32 __user *optval,
596 int __user *optlen)
598 const struct dccp_sock *dp = dccp_sk(sk);
599 const struct dccp_service_list *sl;
600 int err = -ENOENT, slen = 0, total_len = sizeof(u32);
602 lock_sock(sk);
603 if ((sl = dp->dccps_service_list) != NULL) {
604 slen = sl->dccpsl_nr * sizeof(u32);
605 total_len += slen;
608 err = -EINVAL;
609 if (total_len > len)
610 goto out;
612 err = 0;
613 if (put_user(total_len, optlen) ||
614 put_user(dp->dccps_service, optval) ||
615 (sl != NULL && copy_to_user(optval + 1, sl->dccpsl_list, slen)))
616 err = -EFAULT;
617 out:
618 release_sock(sk);
619 return err;
622 static int do_dccp_getsockopt(struct sock *sk, int level, int optname,
623 char __user *optval, int __user *optlen)
625 struct dccp_sock *dp;
626 int val, len;
628 if (get_user(len, optlen))
629 return -EFAULT;
631 if (len < (int)sizeof(int))
632 return -EINVAL;
634 dp = dccp_sk(sk);
636 switch (optname) {
637 case DCCP_SOCKOPT_PACKET_SIZE:
638 DCCP_WARN("sockopt(PACKET_SIZE) is deprecated: fix your app\n");
639 return 0;
640 case DCCP_SOCKOPT_SERVICE:
641 return dccp_getsockopt_service(sk, len,
642 (__be32 __user *)optval, optlen);
643 case DCCP_SOCKOPT_GET_CUR_MPS:
644 val = dp->dccps_mss_cache;
645 break;
646 case DCCP_SOCKOPT_SERVER_TIMEWAIT:
647 val = dp->dccps_server_timewait;
648 break;
649 case DCCP_SOCKOPT_SEND_CSCOV:
650 val = dp->dccps_pcslen;
651 break;
652 case DCCP_SOCKOPT_RECV_CSCOV:
653 val = dp->dccps_pcrlen;
654 break;
655 case 128 ... 191:
656 return ccid_hc_rx_getsockopt(dp->dccps_hc_rx_ccid, sk, optname,
657 len, (u32 __user *)optval, optlen);
658 case 192 ... 255:
659 return ccid_hc_tx_getsockopt(dp->dccps_hc_tx_ccid, sk, optname,
660 len, (u32 __user *)optval, optlen);
661 default:
662 return -ENOPROTOOPT;
665 len = sizeof(val);
666 if (put_user(len, optlen) || copy_to_user(optval, &val, len))
667 return -EFAULT;
669 return 0;
672 int dccp_getsockopt(struct sock *sk, int level, int optname,
673 char __user *optval, int __user *optlen)
675 if (level != SOL_DCCP)
676 return inet_csk(sk)->icsk_af_ops->getsockopt(sk, level,
677 optname, optval,
678 optlen);
679 return do_dccp_getsockopt(sk, level, optname, optval, optlen);
682 EXPORT_SYMBOL_GPL(dccp_getsockopt);
684 #ifdef CONFIG_COMPAT
685 int compat_dccp_getsockopt(struct sock *sk, int level, int optname,
686 char __user *optval, int __user *optlen)
688 if (level != SOL_DCCP)
689 return inet_csk_compat_getsockopt(sk, level, optname,
690 optval, optlen);
691 return do_dccp_getsockopt(sk, level, optname, optval, optlen);
694 EXPORT_SYMBOL_GPL(compat_dccp_getsockopt);
695 #endif
697 int dccp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
698 size_t len)
700 const struct dccp_sock *dp = dccp_sk(sk);
701 const int flags = msg->msg_flags;
702 const int noblock = flags & MSG_DONTWAIT;
703 struct sk_buff *skb;
704 int rc, size;
705 long timeo;
707 if (len > dp->dccps_mss_cache)
708 return -EMSGSIZE;
710 lock_sock(sk);
712 if (sysctl_dccp_tx_qlen &&
713 (sk->sk_write_queue.qlen >= sysctl_dccp_tx_qlen)) {
714 rc = -EAGAIN;
715 goto out_release;
718 timeo = sock_sndtimeo(sk, noblock);
721 * We have to use sk_stream_wait_connect here to set sk_write_pending,
722 * so that the trick in dccp_rcv_request_sent_state_process.
724 /* Wait for a connection to finish. */
725 if ((1 << sk->sk_state) & ~(DCCPF_OPEN | DCCPF_PARTOPEN))
726 if ((rc = sk_stream_wait_connect(sk, &timeo)) != 0)
727 goto out_release;
729 size = sk->sk_prot->max_header + len;
730 release_sock(sk);
731 skb = sock_alloc_send_skb(sk, size, noblock, &rc);
732 lock_sock(sk);
733 if (skb == NULL)
734 goto out_release;
736 skb_reserve(skb, sk->sk_prot->max_header);
737 rc = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
738 if (rc != 0)
739 goto out_discard;
741 skb_queue_tail(&sk->sk_write_queue, skb);
742 dccp_write_xmit(sk,0);
743 out_release:
744 release_sock(sk);
745 return rc ? : len;
746 out_discard:
747 kfree_skb(skb);
748 goto out_release;
751 EXPORT_SYMBOL_GPL(dccp_sendmsg);
753 int dccp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
754 size_t len, int nonblock, int flags, int *addr_len)
756 const struct dccp_hdr *dh;
757 long timeo;
759 lock_sock(sk);
761 if (sk->sk_state == DCCP_LISTEN) {
762 len = -ENOTCONN;
763 goto out;
766 timeo = sock_rcvtimeo(sk, nonblock);
768 do {
769 struct sk_buff *skb = skb_peek(&sk->sk_receive_queue);
771 if (skb == NULL)
772 goto verify_sock_status;
774 dh = dccp_hdr(skb);
776 switch (dh->dccph_type) {
777 case DCCP_PKT_DATA:
778 case DCCP_PKT_DATAACK:
779 goto found_ok_skb;
781 case DCCP_PKT_CLOSE:
782 case DCCP_PKT_CLOSEREQ:
783 if (!(flags & MSG_PEEK))
784 dccp_finish_passive_close(sk);
785 /* fall through */
786 case DCCP_PKT_RESET:
787 dccp_pr_debug("found fin (%s) ok!\n",
788 dccp_packet_name(dh->dccph_type));
789 len = 0;
790 goto found_fin_ok;
791 default:
792 dccp_pr_debug("packet_type=%s\n",
793 dccp_packet_name(dh->dccph_type));
794 sk_eat_skb(sk, skb, 0);
796 verify_sock_status:
797 if (sock_flag(sk, SOCK_DONE)) {
798 len = 0;
799 break;
802 if (sk->sk_err) {
803 len = sock_error(sk);
804 break;
807 if (sk->sk_shutdown & RCV_SHUTDOWN) {
808 len = 0;
809 break;
812 if (sk->sk_state == DCCP_CLOSED) {
813 if (!sock_flag(sk, SOCK_DONE)) {
814 /* This occurs when user tries to read
815 * from never connected socket.
817 len = -ENOTCONN;
818 break;
820 len = 0;
821 break;
824 if (!timeo) {
825 len = -EAGAIN;
826 break;
829 if (signal_pending(current)) {
830 len = sock_intr_errno(timeo);
831 break;
834 sk_wait_data(sk, &timeo);
835 continue;
836 found_ok_skb:
837 if (len > skb->len)
838 len = skb->len;
839 else if (len < skb->len)
840 msg->msg_flags |= MSG_TRUNC;
842 if (skb_copy_datagram_iovec(skb, 0, msg->msg_iov, len)) {
843 /* Exception. Bailout! */
844 len = -EFAULT;
845 break;
847 found_fin_ok:
848 if (!(flags & MSG_PEEK))
849 sk_eat_skb(sk, skb, 0);
850 break;
851 } while (1);
852 out:
853 release_sock(sk);
854 return len;
857 EXPORT_SYMBOL_GPL(dccp_recvmsg);
859 int inet_dccp_listen(struct socket *sock, int backlog)
861 struct sock *sk = sock->sk;
862 unsigned char old_state;
863 int err;
865 lock_sock(sk);
867 err = -EINVAL;
868 if (sock->state != SS_UNCONNECTED || sock->type != SOCK_DCCP)
869 goto out;
871 old_state = sk->sk_state;
872 if (!((1 << old_state) & (DCCPF_CLOSED | DCCPF_LISTEN)))
873 goto out;
875 /* Really, if the socket is already in listen state
876 * we can only allow the backlog to be adjusted.
878 if (old_state != DCCP_LISTEN) {
880 * FIXME: here it probably should be sk->sk_prot->listen_start
881 * see tcp_listen_start
883 err = dccp_listen_start(sk, backlog);
884 if (err)
885 goto out;
887 sk->sk_max_ack_backlog = backlog;
888 err = 0;
890 out:
891 release_sock(sk);
892 return err;
895 EXPORT_SYMBOL_GPL(inet_dccp_listen);
897 static void dccp_terminate_connection(struct sock *sk)
899 u8 next_state = DCCP_CLOSED;
901 switch (sk->sk_state) {
902 case DCCP_PASSIVE_CLOSE:
903 case DCCP_PASSIVE_CLOSEREQ:
904 dccp_finish_passive_close(sk);
905 break;
906 case DCCP_PARTOPEN:
907 dccp_pr_debug("Stop PARTOPEN timer (%p)\n", sk);
908 inet_csk_clear_xmit_timer(sk, ICSK_TIME_DACK);
909 /* fall through */
910 case DCCP_OPEN:
911 dccp_send_close(sk, 1);
913 if (dccp_sk(sk)->dccps_role == DCCP_ROLE_SERVER &&
914 !dccp_sk(sk)->dccps_server_timewait)
915 next_state = DCCP_ACTIVE_CLOSEREQ;
916 else
917 next_state = DCCP_CLOSING;
918 /* fall through */
919 default:
920 dccp_set_state(sk, next_state);
924 void dccp_close(struct sock *sk, long timeout)
926 struct dccp_sock *dp = dccp_sk(sk);
927 struct sk_buff *skb;
928 u32 data_was_unread = 0;
929 int state;
931 lock_sock(sk);
933 sk->sk_shutdown = SHUTDOWN_MASK;
935 if (sk->sk_state == DCCP_LISTEN) {
936 dccp_set_state(sk, DCCP_CLOSED);
938 /* Special case. */
939 inet_csk_listen_stop(sk);
941 goto adjudge_to_death;
944 sk_stop_timer(sk, &dp->dccps_xmit_timer);
947 * We need to flush the recv. buffs. We do this only on the
948 * descriptor close, not protocol-sourced closes, because the
949 *reader process may not have drained the data yet!
951 while ((skb = __skb_dequeue(&sk->sk_receive_queue)) != NULL) {
952 data_was_unread += skb->len;
953 __kfree_skb(skb);
956 if (data_was_unread) {
957 /* Unread data was tossed, send an appropriate Reset Code */
958 DCCP_WARN("DCCP: ABORT -- %u bytes unread\n", data_was_unread);
959 dccp_send_reset(sk, DCCP_RESET_CODE_ABORTED);
960 dccp_set_state(sk, DCCP_CLOSED);
961 } else if (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime) {
962 /* Check zero linger _after_ checking for unread data. */
963 sk->sk_prot->disconnect(sk, 0);
964 } else if (sk->sk_state != DCCP_CLOSED) {
965 dccp_terminate_connection(sk);
968 sk_stream_wait_close(sk, timeout);
970 adjudge_to_death:
971 state = sk->sk_state;
972 sock_hold(sk);
973 sock_orphan(sk);
974 atomic_inc(sk->sk_prot->orphan_count);
977 * It is the last release_sock in its life. It will remove backlog.
979 release_sock(sk);
981 * Now socket is owned by kernel and we acquire BH lock
982 * to finish close. No need to check for user refs.
984 local_bh_disable();
985 bh_lock_sock(sk);
986 BUG_TRAP(!sock_owned_by_user(sk));
988 /* Have we already been destroyed by a softirq or backlog? */
989 if (state != DCCP_CLOSED && sk->sk_state == DCCP_CLOSED)
990 goto out;
992 if (sk->sk_state == DCCP_CLOSED)
993 inet_csk_destroy_sock(sk);
995 /* Otherwise, socket is reprieved until protocol close. */
997 out:
998 bh_unlock_sock(sk);
999 local_bh_enable();
1000 sock_put(sk);
1003 EXPORT_SYMBOL_GPL(dccp_close);
1005 void dccp_shutdown(struct sock *sk, int how)
1007 dccp_pr_debug("called shutdown(%x)\n", how);
1010 EXPORT_SYMBOL_GPL(dccp_shutdown);
1012 static inline int dccp_mib_init(void)
1014 return snmp_mib_init((void**)dccp_statistics, sizeof(struct dccp_mib));
1017 static inline void dccp_mib_exit(void)
1019 snmp_mib_free((void**)dccp_statistics);
1022 static int thash_entries;
1023 module_param(thash_entries, int, 0444);
1024 MODULE_PARM_DESC(thash_entries, "Number of ehash buckets");
1026 #ifdef CONFIG_IP_DCCP_DEBUG
1027 int dccp_debug;
1028 module_param(dccp_debug, bool, 0444);
1029 MODULE_PARM_DESC(dccp_debug, "Enable debug messages");
1031 EXPORT_SYMBOL_GPL(dccp_debug);
1032 #endif
1034 static int __init dccp_init(void)
1036 unsigned long goal;
1037 int ehash_order, bhash_order, i;
1038 int rc = -ENOBUFS;
1040 BUILD_BUG_ON(sizeof(struct dccp_skb_cb) >
1041 FIELD_SIZEOF(struct sk_buff, cb));
1043 dccp_hashinfo.bind_bucket_cachep =
1044 kmem_cache_create("dccp_bind_bucket",
1045 sizeof(struct inet_bind_bucket), 0,
1046 SLAB_HWCACHE_ALIGN, NULL);
1047 if (!dccp_hashinfo.bind_bucket_cachep)
1048 goto out;
1051 * Size and allocate the main established and bind bucket
1052 * hash tables.
1054 * The methodology is similar to that of the buffer cache.
1056 if (num_physpages >= (128 * 1024))
1057 goal = num_physpages >> (21 - PAGE_SHIFT);
1058 else
1059 goal = num_physpages >> (23 - PAGE_SHIFT);
1061 if (thash_entries)
1062 goal = (thash_entries *
1063 sizeof(struct inet_ehash_bucket)) >> PAGE_SHIFT;
1064 for (ehash_order = 0; (1UL << ehash_order) < goal; ehash_order++)
1066 do {
1067 dccp_hashinfo.ehash_size = (1UL << ehash_order) * PAGE_SIZE /
1068 sizeof(struct inet_ehash_bucket);
1069 while (dccp_hashinfo.ehash_size &
1070 (dccp_hashinfo.ehash_size - 1))
1071 dccp_hashinfo.ehash_size--;
1072 dccp_hashinfo.ehash = (struct inet_ehash_bucket *)
1073 __get_free_pages(GFP_ATOMIC, ehash_order);
1074 } while (!dccp_hashinfo.ehash && --ehash_order > 0);
1076 if (!dccp_hashinfo.ehash) {
1077 DCCP_CRIT("Failed to allocate DCCP established hash table");
1078 goto out_free_bind_bucket_cachep;
1081 for (i = 0; i < dccp_hashinfo.ehash_size; i++) {
1082 INIT_HLIST_HEAD(&dccp_hashinfo.ehash[i].chain);
1083 INIT_HLIST_HEAD(&dccp_hashinfo.ehash[i].twchain);
1086 if (inet_ehash_locks_alloc(&dccp_hashinfo))
1087 goto out_free_dccp_ehash;
1089 bhash_order = ehash_order;
1091 do {
1092 dccp_hashinfo.bhash_size = (1UL << bhash_order) * PAGE_SIZE /
1093 sizeof(struct inet_bind_hashbucket);
1094 if ((dccp_hashinfo.bhash_size > (64 * 1024)) &&
1095 bhash_order > 0)
1096 continue;
1097 dccp_hashinfo.bhash = (struct inet_bind_hashbucket *)
1098 __get_free_pages(GFP_ATOMIC, bhash_order);
1099 } while (!dccp_hashinfo.bhash && --bhash_order >= 0);
1101 if (!dccp_hashinfo.bhash) {
1102 DCCP_CRIT("Failed to allocate DCCP bind hash table");
1103 goto out_free_dccp_locks;
1106 for (i = 0; i < dccp_hashinfo.bhash_size; i++) {
1107 spin_lock_init(&dccp_hashinfo.bhash[i].lock);
1108 INIT_HLIST_HEAD(&dccp_hashinfo.bhash[i].chain);
1111 rc = dccp_mib_init();
1112 if (rc)
1113 goto out_free_dccp_bhash;
1115 rc = dccp_ackvec_init();
1116 if (rc)
1117 goto out_free_dccp_mib;
1119 rc = dccp_sysctl_init();
1120 if (rc)
1121 goto out_ackvec_exit;
1123 dccp_timestamping_init();
1124 out:
1125 return rc;
1126 out_ackvec_exit:
1127 dccp_ackvec_exit();
1128 out_free_dccp_mib:
1129 dccp_mib_exit();
1130 out_free_dccp_bhash:
1131 free_pages((unsigned long)dccp_hashinfo.bhash, bhash_order);
1132 dccp_hashinfo.bhash = NULL;
1133 out_free_dccp_locks:
1134 inet_ehash_locks_free(&dccp_hashinfo);
1135 out_free_dccp_ehash:
1136 free_pages((unsigned long)dccp_hashinfo.ehash, ehash_order);
1137 dccp_hashinfo.ehash = NULL;
1138 out_free_bind_bucket_cachep:
1139 kmem_cache_destroy(dccp_hashinfo.bind_bucket_cachep);
1140 dccp_hashinfo.bind_bucket_cachep = NULL;
1141 goto out;
1144 static void __exit dccp_fini(void)
1146 dccp_mib_exit();
1147 free_pages((unsigned long)dccp_hashinfo.bhash,
1148 get_order(dccp_hashinfo.bhash_size *
1149 sizeof(struct inet_bind_hashbucket)));
1150 free_pages((unsigned long)dccp_hashinfo.ehash,
1151 get_order(dccp_hashinfo.ehash_size *
1152 sizeof(struct inet_ehash_bucket)));
1153 inet_ehash_locks_free(&dccp_hashinfo);
1154 kmem_cache_destroy(dccp_hashinfo.bind_bucket_cachep);
1155 dccp_ackvec_exit();
1156 dccp_sysctl_exit();
1159 module_init(dccp_init);
1160 module_exit(dccp_fini);
1162 MODULE_LICENSE("GPL");
1163 MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@conectiva.com.br>");
1164 MODULE_DESCRIPTION("DCCP - Datagram Congestion Controlled Protocol");