Save sram context after changing MPU, DSP or core clocks
[linux-ginger.git] / net / dccp / proto.c
bloba156319fd0acd53a65cfae08992d97c27c9a1058
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 struct percpu_counter dccp_orphan_count;
44 EXPORT_SYMBOL_GPL(dccp_orphan_count);
46 struct inet_hashinfo dccp_hashinfo;
47 EXPORT_SYMBOL_GPL(dccp_hashinfo);
49 /* the maximum queue length for tx in packets. 0 is no limit */
50 int sysctl_dccp_tx_qlen __read_mostly = 5;
52 void dccp_set_state(struct sock *sk, const int state)
54 const int oldstate = sk->sk_state;
56 dccp_pr_debug("%s(%p) %s --> %s\n", dccp_role(sk), sk,
57 dccp_state_name(oldstate), dccp_state_name(state));
58 WARN_ON(state == oldstate);
60 switch (state) {
61 case DCCP_OPEN:
62 if (oldstate != DCCP_OPEN)
63 DCCP_INC_STATS(DCCP_MIB_CURRESTAB);
64 /* Client retransmits all Confirm options until entering OPEN */
65 if (oldstate == DCCP_PARTOPEN)
66 dccp_feat_list_purge(&dccp_sk(sk)->dccps_featneg);
67 break;
69 case DCCP_CLOSED:
70 if (oldstate == DCCP_OPEN || oldstate == DCCP_ACTIVE_CLOSEREQ ||
71 oldstate == DCCP_CLOSING)
72 DCCP_INC_STATS(DCCP_MIB_ESTABRESETS);
74 sk->sk_prot->unhash(sk);
75 if (inet_csk(sk)->icsk_bind_hash != NULL &&
76 !(sk->sk_userlocks & SOCK_BINDPORT_LOCK))
77 inet_put_port(sk);
78 /* fall through */
79 default:
80 if (oldstate == DCCP_OPEN)
81 DCCP_DEC_STATS(DCCP_MIB_CURRESTAB);
84 /* Change state AFTER socket is unhashed to avoid closed
85 * socket sitting in hash tables.
87 sk->sk_state = state;
90 EXPORT_SYMBOL_GPL(dccp_set_state);
92 static void dccp_finish_passive_close(struct sock *sk)
94 switch (sk->sk_state) {
95 case DCCP_PASSIVE_CLOSE:
96 /* Node (client or server) has received Close packet. */
97 dccp_send_reset(sk, DCCP_RESET_CODE_CLOSED);
98 dccp_set_state(sk, DCCP_CLOSED);
99 break;
100 case DCCP_PASSIVE_CLOSEREQ:
102 * Client received CloseReq. We set the `active' flag so that
103 * dccp_send_close() retransmits the Close as per RFC 4340, 8.3.
105 dccp_send_close(sk, 1);
106 dccp_set_state(sk, DCCP_CLOSING);
110 void dccp_done(struct sock *sk)
112 dccp_set_state(sk, DCCP_CLOSED);
113 dccp_clear_xmit_timers(sk);
115 sk->sk_shutdown = SHUTDOWN_MASK;
117 if (!sock_flag(sk, SOCK_DEAD))
118 sk->sk_state_change(sk);
119 else
120 inet_csk_destroy_sock(sk);
123 EXPORT_SYMBOL_GPL(dccp_done);
125 const char *dccp_packet_name(const int type)
127 static const char *const dccp_packet_names[] = {
128 [DCCP_PKT_REQUEST] = "REQUEST",
129 [DCCP_PKT_RESPONSE] = "RESPONSE",
130 [DCCP_PKT_DATA] = "DATA",
131 [DCCP_PKT_ACK] = "ACK",
132 [DCCP_PKT_DATAACK] = "DATAACK",
133 [DCCP_PKT_CLOSEREQ] = "CLOSEREQ",
134 [DCCP_PKT_CLOSE] = "CLOSE",
135 [DCCP_PKT_RESET] = "RESET",
136 [DCCP_PKT_SYNC] = "SYNC",
137 [DCCP_PKT_SYNCACK] = "SYNCACK",
140 if (type >= DCCP_NR_PKT_TYPES)
141 return "INVALID";
142 else
143 return dccp_packet_names[type];
146 EXPORT_SYMBOL_GPL(dccp_packet_name);
148 const char *dccp_state_name(const int state)
150 static const char *const dccp_state_names[] = {
151 [DCCP_OPEN] = "OPEN",
152 [DCCP_REQUESTING] = "REQUESTING",
153 [DCCP_PARTOPEN] = "PARTOPEN",
154 [DCCP_LISTEN] = "LISTEN",
155 [DCCP_RESPOND] = "RESPOND",
156 [DCCP_CLOSING] = "CLOSING",
157 [DCCP_ACTIVE_CLOSEREQ] = "CLOSEREQ",
158 [DCCP_PASSIVE_CLOSE] = "PASSIVE_CLOSE",
159 [DCCP_PASSIVE_CLOSEREQ] = "PASSIVE_CLOSEREQ",
160 [DCCP_TIME_WAIT] = "TIME_WAIT",
161 [DCCP_CLOSED] = "CLOSED",
164 if (state >= DCCP_MAX_STATES)
165 return "INVALID STATE!";
166 else
167 return dccp_state_names[state];
170 EXPORT_SYMBOL_GPL(dccp_state_name);
172 int dccp_init_sock(struct sock *sk, const __u8 ctl_sock_initialized)
174 struct dccp_sock *dp = dccp_sk(sk);
175 struct inet_connection_sock *icsk = inet_csk(sk);
177 icsk->icsk_rto = DCCP_TIMEOUT_INIT;
178 icsk->icsk_syn_retries = sysctl_dccp_request_retries;
179 sk->sk_state = DCCP_CLOSED;
180 sk->sk_write_space = dccp_write_space;
181 icsk->icsk_sync_mss = dccp_sync_mss;
182 dp->dccps_mss_cache = 536;
183 dp->dccps_rate_last = jiffies;
184 dp->dccps_role = DCCP_ROLE_UNDEFINED;
185 dp->dccps_service = DCCP_SERVICE_CODE_IS_ABSENT;
186 dp->dccps_l_ack_ratio = dp->dccps_r_ack_ratio = 1;
188 dccp_init_xmit_timers(sk);
190 INIT_LIST_HEAD(&dp->dccps_featneg);
191 /* control socket doesn't need feat nego */
192 if (likely(ctl_sock_initialized))
193 return dccp_feat_init(sk);
194 return 0;
197 EXPORT_SYMBOL_GPL(dccp_init_sock);
199 void dccp_destroy_sock(struct sock *sk)
201 struct dccp_sock *dp = dccp_sk(sk);
204 * DCCP doesn't use sk_write_queue, just sk_send_head
205 * for retransmissions
207 if (sk->sk_send_head != NULL) {
208 kfree_skb(sk->sk_send_head);
209 sk->sk_send_head = NULL;
212 /* Clean up a referenced DCCP bind bucket. */
213 if (inet_csk(sk)->icsk_bind_hash != NULL)
214 inet_put_port(sk);
216 kfree(dp->dccps_service_list);
217 dp->dccps_service_list = NULL;
219 if (dp->dccps_hc_rx_ackvec != NULL) {
220 dccp_ackvec_free(dp->dccps_hc_rx_ackvec);
221 dp->dccps_hc_rx_ackvec = NULL;
223 ccid_hc_rx_delete(dp->dccps_hc_rx_ccid, sk);
224 ccid_hc_tx_delete(dp->dccps_hc_tx_ccid, sk);
225 dp->dccps_hc_rx_ccid = dp->dccps_hc_tx_ccid = NULL;
227 /* clean up feature negotiation state */
228 dccp_feat_list_purge(&dp->dccps_featneg);
231 EXPORT_SYMBOL_GPL(dccp_destroy_sock);
233 static inline int dccp_listen_start(struct sock *sk, int backlog)
235 struct dccp_sock *dp = dccp_sk(sk);
237 dp->dccps_role = DCCP_ROLE_LISTEN;
238 /* do not start to listen if feature negotiation setup fails */
239 if (dccp_feat_finalise_settings(dp))
240 return -EPROTO;
241 return inet_csk_listen_start(sk, backlog);
244 static inline int dccp_need_reset(int state)
246 return state != DCCP_CLOSED && state != DCCP_LISTEN &&
247 state != DCCP_REQUESTING;
250 int dccp_disconnect(struct sock *sk, int flags)
252 struct inet_connection_sock *icsk = inet_csk(sk);
253 struct inet_sock *inet = inet_sk(sk);
254 int err = 0;
255 const int old_state = sk->sk_state;
257 if (old_state != DCCP_CLOSED)
258 dccp_set_state(sk, DCCP_CLOSED);
261 * This corresponds to the ABORT function of RFC793, sec. 3.8
262 * TCP uses a RST segment, DCCP a Reset packet with Code 2, "Aborted".
264 if (old_state == DCCP_LISTEN) {
265 inet_csk_listen_stop(sk);
266 } else if (dccp_need_reset(old_state)) {
267 dccp_send_reset(sk, DCCP_RESET_CODE_ABORTED);
268 sk->sk_err = ECONNRESET;
269 } else if (old_state == DCCP_REQUESTING)
270 sk->sk_err = ECONNRESET;
272 dccp_clear_xmit_timers(sk);
274 __skb_queue_purge(&sk->sk_receive_queue);
275 __skb_queue_purge(&sk->sk_write_queue);
276 if (sk->sk_send_head != NULL) {
277 __kfree_skb(sk->sk_send_head);
278 sk->sk_send_head = NULL;
281 inet->dport = 0;
283 if (!(sk->sk_userlocks & SOCK_BINDADDR_LOCK))
284 inet_reset_saddr(sk);
286 sk->sk_shutdown = 0;
287 sock_reset_flag(sk, SOCK_DONE);
289 icsk->icsk_backoff = 0;
290 inet_csk_delack_init(sk);
291 __sk_dst_reset(sk);
293 WARN_ON(inet->num && !icsk->icsk_bind_hash);
295 sk->sk_error_report(sk);
296 return err;
299 EXPORT_SYMBOL_GPL(dccp_disconnect);
302 * Wait for a DCCP event.
304 * Note that we don't need to lock the socket, as the upper poll layers
305 * take care of normal races (between the test and the event) and we don't
306 * go look at any of the socket buffers directly.
308 unsigned int dccp_poll(struct file *file, struct socket *sock,
309 poll_table *wait)
311 unsigned int mask;
312 struct sock *sk = sock->sk;
314 sock_poll_wait(file, sk->sk_sleep, wait);
315 if (sk->sk_state == DCCP_LISTEN)
316 return inet_csk_listen_poll(sk);
318 /* Socket is not locked. We are protected from async events
319 by poll logic and correct handling of state changes
320 made by another threads is impossible in any case.
323 mask = 0;
324 if (sk->sk_err)
325 mask = POLLERR;
327 if (sk->sk_shutdown == SHUTDOWN_MASK || sk->sk_state == DCCP_CLOSED)
328 mask |= POLLHUP;
329 if (sk->sk_shutdown & RCV_SHUTDOWN)
330 mask |= POLLIN | POLLRDNORM | POLLRDHUP;
332 /* Connected? */
333 if ((1 << sk->sk_state) & ~(DCCPF_REQUESTING | DCCPF_RESPOND)) {
334 if (atomic_read(&sk->sk_rmem_alloc) > 0)
335 mask |= POLLIN | POLLRDNORM;
337 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
338 if (sk_stream_wspace(sk) >= sk_stream_min_wspace(sk)) {
339 mask |= POLLOUT | POLLWRNORM;
340 } else { /* send SIGIO later */
341 set_bit(SOCK_ASYNC_NOSPACE,
342 &sk->sk_socket->flags);
343 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
345 /* Race breaker. If space is freed after
346 * wspace test but before the flags are set,
347 * IO signal will be lost.
349 if (sk_stream_wspace(sk) >= sk_stream_min_wspace(sk))
350 mask |= POLLOUT | POLLWRNORM;
354 return mask;
357 EXPORT_SYMBOL_GPL(dccp_poll);
359 int dccp_ioctl(struct sock *sk, int cmd, unsigned long arg)
361 int rc = -ENOTCONN;
363 lock_sock(sk);
365 if (sk->sk_state == DCCP_LISTEN)
366 goto out;
368 switch (cmd) {
369 case SIOCINQ: {
370 struct sk_buff *skb;
371 unsigned long amount = 0;
373 skb = skb_peek(&sk->sk_receive_queue);
374 if (skb != NULL) {
376 * We will only return the amount of this packet since
377 * that is all that will be read.
379 amount = skb->len;
381 rc = put_user(amount, (int __user *)arg);
383 break;
384 default:
385 rc = -ENOIOCTLCMD;
386 break;
388 out:
389 release_sock(sk);
390 return rc;
393 EXPORT_SYMBOL_GPL(dccp_ioctl);
395 static int dccp_setsockopt_service(struct sock *sk, const __be32 service,
396 char __user *optval, unsigned int optlen)
398 struct dccp_sock *dp = dccp_sk(sk);
399 struct dccp_service_list *sl = NULL;
401 if (service == DCCP_SERVICE_INVALID_VALUE ||
402 optlen > DCCP_SERVICE_LIST_MAX_LEN * sizeof(u32))
403 return -EINVAL;
405 if (optlen > sizeof(service)) {
406 sl = kmalloc(optlen, GFP_KERNEL);
407 if (sl == NULL)
408 return -ENOMEM;
410 sl->dccpsl_nr = optlen / sizeof(u32) - 1;
411 if (copy_from_user(sl->dccpsl_list,
412 optval + sizeof(service),
413 optlen - sizeof(service)) ||
414 dccp_list_has_service(sl, DCCP_SERVICE_INVALID_VALUE)) {
415 kfree(sl);
416 return -EFAULT;
420 lock_sock(sk);
421 dp->dccps_service = service;
423 kfree(dp->dccps_service_list);
425 dp->dccps_service_list = sl;
426 release_sock(sk);
427 return 0;
430 static int dccp_setsockopt_cscov(struct sock *sk, int cscov, bool rx)
432 u8 *list, len;
433 int i, rc;
435 if (cscov < 0 || cscov > 15)
436 return -EINVAL;
438 * Populate a list of permissible values, in the range cscov...15. This
439 * is necessary since feature negotiation of single values only works if
440 * both sides incidentally choose the same value. Since the list starts
441 * lowest-value first, negotiation will pick the smallest shared value.
443 if (cscov == 0)
444 return 0;
445 len = 16 - cscov;
447 list = kmalloc(len, GFP_KERNEL);
448 if (list == NULL)
449 return -ENOBUFS;
451 for (i = 0; i < len; i++)
452 list[i] = cscov++;
454 rc = dccp_feat_register_sp(sk, DCCPF_MIN_CSUM_COVER, rx, list, len);
456 if (rc == 0) {
457 if (rx)
458 dccp_sk(sk)->dccps_pcrlen = cscov;
459 else
460 dccp_sk(sk)->dccps_pcslen = cscov;
462 kfree(list);
463 return rc;
466 static int dccp_setsockopt_ccid(struct sock *sk, int type,
467 char __user *optval, unsigned int optlen)
469 u8 *val;
470 int rc = 0;
472 if (optlen < 1 || optlen > DCCP_FEAT_MAX_SP_VALS)
473 return -EINVAL;
475 val = kmalloc(optlen, GFP_KERNEL);
476 if (val == NULL)
477 return -ENOMEM;
479 if (copy_from_user(val, optval, optlen)) {
480 kfree(val);
481 return -EFAULT;
484 lock_sock(sk);
485 if (type == DCCP_SOCKOPT_TX_CCID || type == DCCP_SOCKOPT_CCID)
486 rc = dccp_feat_register_sp(sk, DCCPF_CCID, 1, val, optlen);
488 if (!rc && (type == DCCP_SOCKOPT_RX_CCID || type == DCCP_SOCKOPT_CCID))
489 rc = dccp_feat_register_sp(sk, DCCPF_CCID, 0, val, optlen);
490 release_sock(sk);
492 kfree(val);
493 return rc;
496 static int do_dccp_setsockopt(struct sock *sk, int level, int optname,
497 char __user *optval, unsigned int optlen)
499 struct dccp_sock *dp = dccp_sk(sk);
500 int val, err = 0;
502 switch (optname) {
503 case DCCP_SOCKOPT_PACKET_SIZE:
504 DCCP_WARN("sockopt(PACKET_SIZE) is deprecated: fix your app\n");
505 return 0;
506 case DCCP_SOCKOPT_CHANGE_L:
507 case DCCP_SOCKOPT_CHANGE_R:
508 DCCP_WARN("sockopt(CHANGE_L/R) is deprecated: fix your app\n");
509 return 0;
510 case DCCP_SOCKOPT_CCID:
511 case DCCP_SOCKOPT_RX_CCID:
512 case DCCP_SOCKOPT_TX_CCID:
513 return dccp_setsockopt_ccid(sk, optname, optval, optlen);
516 if (optlen < (int)sizeof(int))
517 return -EINVAL;
519 if (get_user(val, (int __user *)optval))
520 return -EFAULT;
522 if (optname == DCCP_SOCKOPT_SERVICE)
523 return dccp_setsockopt_service(sk, val, optval, optlen);
525 lock_sock(sk);
526 switch (optname) {
527 case DCCP_SOCKOPT_SERVER_TIMEWAIT:
528 if (dp->dccps_role != DCCP_ROLE_SERVER)
529 err = -EOPNOTSUPP;
530 else
531 dp->dccps_server_timewait = (val != 0);
532 break;
533 case DCCP_SOCKOPT_SEND_CSCOV:
534 err = dccp_setsockopt_cscov(sk, val, false);
535 break;
536 case DCCP_SOCKOPT_RECV_CSCOV:
537 err = dccp_setsockopt_cscov(sk, val, true);
538 break;
539 default:
540 err = -ENOPROTOOPT;
541 break;
543 release_sock(sk);
545 return err;
548 int dccp_setsockopt(struct sock *sk, int level, int optname,
549 char __user *optval, unsigned int optlen)
551 if (level != SOL_DCCP)
552 return inet_csk(sk)->icsk_af_ops->setsockopt(sk, level,
553 optname, optval,
554 optlen);
555 return do_dccp_setsockopt(sk, level, optname, optval, optlen);
558 EXPORT_SYMBOL_GPL(dccp_setsockopt);
560 #ifdef CONFIG_COMPAT
561 int compat_dccp_setsockopt(struct sock *sk, int level, int optname,
562 char __user *optval, unsigned int optlen)
564 if (level != SOL_DCCP)
565 return inet_csk_compat_setsockopt(sk, level, optname,
566 optval, optlen);
567 return do_dccp_setsockopt(sk, level, optname, optval, optlen);
570 EXPORT_SYMBOL_GPL(compat_dccp_setsockopt);
571 #endif
573 static int dccp_getsockopt_service(struct sock *sk, int len,
574 __be32 __user *optval,
575 int __user *optlen)
577 const struct dccp_sock *dp = dccp_sk(sk);
578 const struct dccp_service_list *sl;
579 int err = -ENOENT, slen = 0, total_len = sizeof(u32);
581 lock_sock(sk);
582 if ((sl = dp->dccps_service_list) != NULL) {
583 slen = sl->dccpsl_nr * sizeof(u32);
584 total_len += slen;
587 err = -EINVAL;
588 if (total_len > len)
589 goto out;
591 err = 0;
592 if (put_user(total_len, optlen) ||
593 put_user(dp->dccps_service, optval) ||
594 (sl != NULL && copy_to_user(optval + 1, sl->dccpsl_list, slen)))
595 err = -EFAULT;
596 out:
597 release_sock(sk);
598 return err;
601 static int do_dccp_getsockopt(struct sock *sk, int level, int optname,
602 char __user *optval, int __user *optlen)
604 struct dccp_sock *dp;
605 int val, len;
607 if (get_user(len, optlen))
608 return -EFAULT;
610 if (len < (int)sizeof(int))
611 return -EINVAL;
613 dp = dccp_sk(sk);
615 switch (optname) {
616 case DCCP_SOCKOPT_PACKET_SIZE:
617 DCCP_WARN("sockopt(PACKET_SIZE) is deprecated: fix your app\n");
618 return 0;
619 case DCCP_SOCKOPT_SERVICE:
620 return dccp_getsockopt_service(sk, len,
621 (__be32 __user *)optval, optlen);
622 case DCCP_SOCKOPT_GET_CUR_MPS:
623 val = dp->dccps_mss_cache;
624 break;
625 case DCCP_SOCKOPT_AVAILABLE_CCIDS:
626 return ccid_getsockopt_builtin_ccids(sk, len, optval, optlen);
627 case DCCP_SOCKOPT_TX_CCID:
628 val = ccid_get_current_tx_ccid(dp);
629 if (val < 0)
630 return -ENOPROTOOPT;
631 break;
632 case DCCP_SOCKOPT_RX_CCID:
633 val = ccid_get_current_rx_ccid(dp);
634 if (val < 0)
635 return -ENOPROTOOPT;
636 break;
637 case DCCP_SOCKOPT_SERVER_TIMEWAIT:
638 val = dp->dccps_server_timewait;
639 break;
640 case DCCP_SOCKOPT_SEND_CSCOV:
641 val = dp->dccps_pcslen;
642 break;
643 case DCCP_SOCKOPT_RECV_CSCOV:
644 val = dp->dccps_pcrlen;
645 break;
646 case 128 ... 191:
647 return ccid_hc_rx_getsockopt(dp->dccps_hc_rx_ccid, sk, optname,
648 len, (u32 __user *)optval, optlen);
649 case 192 ... 255:
650 return ccid_hc_tx_getsockopt(dp->dccps_hc_tx_ccid, sk, optname,
651 len, (u32 __user *)optval, optlen);
652 default:
653 return -ENOPROTOOPT;
656 len = sizeof(val);
657 if (put_user(len, optlen) || copy_to_user(optval, &val, len))
658 return -EFAULT;
660 return 0;
663 int dccp_getsockopt(struct sock *sk, int level, int optname,
664 char __user *optval, int __user *optlen)
666 if (level != SOL_DCCP)
667 return inet_csk(sk)->icsk_af_ops->getsockopt(sk, level,
668 optname, optval,
669 optlen);
670 return do_dccp_getsockopt(sk, level, optname, optval, optlen);
673 EXPORT_SYMBOL_GPL(dccp_getsockopt);
675 #ifdef CONFIG_COMPAT
676 int compat_dccp_getsockopt(struct sock *sk, int level, int optname,
677 char __user *optval, int __user *optlen)
679 if (level != SOL_DCCP)
680 return inet_csk_compat_getsockopt(sk, level, optname,
681 optval, optlen);
682 return do_dccp_getsockopt(sk, level, optname, optval, optlen);
685 EXPORT_SYMBOL_GPL(compat_dccp_getsockopt);
686 #endif
688 int dccp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
689 size_t len)
691 const struct dccp_sock *dp = dccp_sk(sk);
692 const int flags = msg->msg_flags;
693 const int noblock = flags & MSG_DONTWAIT;
694 struct sk_buff *skb;
695 int rc, size;
696 long timeo;
698 if (len > dp->dccps_mss_cache)
699 return -EMSGSIZE;
701 lock_sock(sk);
703 if (sysctl_dccp_tx_qlen &&
704 (sk->sk_write_queue.qlen >= sysctl_dccp_tx_qlen)) {
705 rc = -EAGAIN;
706 goto out_release;
709 timeo = sock_sndtimeo(sk, noblock);
712 * We have to use sk_stream_wait_connect here to set sk_write_pending,
713 * so that the trick in dccp_rcv_request_sent_state_process.
715 /* Wait for a connection to finish. */
716 if ((1 << sk->sk_state) & ~(DCCPF_OPEN | DCCPF_PARTOPEN))
717 if ((rc = sk_stream_wait_connect(sk, &timeo)) != 0)
718 goto out_release;
720 size = sk->sk_prot->max_header + len;
721 release_sock(sk);
722 skb = sock_alloc_send_skb(sk, size, noblock, &rc);
723 lock_sock(sk);
724 if (skb == NULL)
725 goto out_release;
727 skb_reserve(skb, sk->sk_prot->max_header);
728 rc = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
729 if (rc != 0)
730 goto out_discard;
732 skb_queue_tail(&sk->sk_write_queue, skb);
733 dccp_write_xmit(sk,0);
734 out_release:
735 release_sock(sk);
736 return rc ? : len;
737 out_discard:
738 kfree_skb(skb);
739 goto out_release;
742 EXPORT_SYMBOL_GPL(dccp_sendmsg);
744 int dccp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
745 size_t len, int nonblock, int flags, int *addr_len)
747 const struct dccp_hdr *dh;
748 long timeo;
750 lock_sock(sk);
752 if (sk->sk_state == DCCP_LISTEN) {
753 len = -ENOTCONN;
754 goto out;
757 timeo = sock_rcvtimeo(sk, nonblock);
759 do {
760 struct sk_buff *skb = skb_peek(&sk->sk_receive_queue);
762 if (skb == NULL)
763 goto verify_sock_status;
765 dh = dccp_hdr(skb);
767 switch (dh->dccph_type) {
768 case DCCP_PKT_DATA:
769 case DCCP_PKT_DATAACK:
770 goto found_ok_skb;
772 case DCCP_PKT_CLOSE:
773 case DCCP_PKT_CLOSEREQ:
774 if (!(flags & MSG_PEEK))
775 dccp_finish_passive_close(sk);
776 /* fall through */
777 case DCCP_PKT_RESET:
778 dccp_pr_debug("found fin (%s) ok!\n",
779 dccp_packet_name(dh->dccph_type));
780 len = 0;
781 goto found_fin_ok;
782 default:
783 dccp_pr_debug("packet_type=%s\n",
784 dccp_packet_name(dh->dccph_type));
785 sk_eat_skb(sk, skb, 0);
787 verify_sock_status:
788 if (sock_flag(sk, SOCK_DONE)) {
789 len = 0;
790 break;
793 if (sk->sk_err) {
794 len = sock_error(sk);
795 break;
798 if (sk->sk_shutdown & RCV_SHUTDOWN) {
799 len = 0;
800 break;
803 if (sk->sk_state == DCCP_CLOSED) {
804 if (!sock_flag(sk, SOCK_DONE)) {
805 /* This occurs when user tries to read
806 * from never connected socket.
808 len = -ENOTCONN;
809 break;
811 len = 0;
812 break;
815 if (!timeo) {
816 len = -EAGAIN;
817 break;
820 if (signal_pending(current)) {
821 len = sock_intr_errno(timeo);
822 break;
825 sk_wait_data(sk, &timeo);
826 continue;
827 found_ok_skb:
828 if (len > skb->len)
829 len = skb->len;
830 else if (len < skb->len)
831 msg->msg_flags |= MSG_TRUNC;
833 if (skb_copy_datagram_iovec(skb, 0, msg->msg_iov, len)) {
834 /* Exception. Bailout! */
835 len = -EFAULT;
836 break;
838 found_fin_ok:
839 if (!(flags & MSG_PEEK))
840 sk_eat_skb(sk, skb, 0);
841 break;
842 } while (1);
843 out:
844 release_sock(sk);
845 return len;
848 EXPORT_SYMBOL_GPL(dccp_recvmsg);
850 int inet_dccp_listen(struct socket *sock, int backlog)
852 struct sock *sk = sock->sk;
853 unsigned char old_state;
854 int err;
856 lock_sock(sk);
858 err = -EINVAL;
859 if (sock->state != SS_UNCONNECTED || sock->type != SOCK_DCCP)
860 goto out;
862 old_state = sk->sk_state;
863 if (!((1 << old_state) & (DCCPF_CLOSED | DCCPF_LISTEN)))
864 goto out;
866 /* Really, if the socket is already in listen state
867 * we can only allow the backlog to be adjusted.
869 if (old_state != DCCP_LISTEN) {
871 * FIXME: here it probably should be sk->sk_prot->listen_start
872 * see tcp_listen_start
874 err = dccp_listen_start(sk, backlog);
875 if (err)
876 goto out;
878 sk->sk_max_ack_backlog = backlog;
879 err = 0;
881 out:
882 release_sock(sk);
883 return err;
886 EXPORT_SYMBOL_GPL(inet_dccp_listen);
888 static void dccp_terminate_connection(struct sock *sk)
890 u8 next_state = DCCP_CLOSED;
892 switch (sk->sk_state) {
893 case DCCP_PASSIVE_CLOSE:
894 case DCCP_PASSIVE_CLOSEREQ:
895 dccp_finish_passive_close(sk);
896 break;
897 case DCCP_PARTOPEN:
898 dccp_pr_debug("Stop PARTOPEN timer (%p)\n", sk);
899 inet_csk_clear_xmit_timer(sk, ICSK_TIME_DACK);
900 /* fall through */
901 case DCCP_OPEN:
902 dccp_send_close(sk, 1);
904 if (dccp_sk(sk)->dccps_role == DCCP_ROLE_SERVER &&
905 !dccp_sk(sk)->dccps_server_timewait)
906 next_state = DCCP_ACTIVE_CLOSEREQ;
907 else
908 next_state = DCCP_CLOSING;
909 /* fall through */
910 default:
911 dccp_set_state(sk, next_state);
915 void dccp_close(struct sock *sk, long timeout)
917 struct dccp_sock *dp = dccp_sk(sk);
918 struct sk_buff *skb;
919 u32 data_was_unread = 0;
920 int state;
922 lock_sock(sk);
924 sk->sk_shutdown = SHUTDOWN_MASK;
926 if (sk->sk_state == DCCP_LISTEN) {
927 dccp_set_state(sk, DCCP_CLOSED);
929 /* Special case. */
930 inet_csk_listen_stop(sk);
932 goto adjudge_to_death;
935 sk_stop_timer(sk, &dp->dccps_xmit_timer);
938 * We need to flush the recv. buffs. We do this only on the
939 * descriptor close, not protocol-sourced closes, because the
940 *reader process may not have drained the data yet!
942 while ((skb = __skb_dequeue(&sk->sk_receive_queue)) != NULL) {
943 data_was_unread += skb->len;
944 __kfree_skb(skb);
947 if (data_was_unread) {
948 /* Unread data was tossed, send an appropriate Reset Code */
949 DCCP_WARN("DCCP: ABORT -- %u bytes unread\n", data_was_unread);
950 dccp_send_reset(sk, DCCP_RESET_CODE_ABORTED);
951 dccp_set_state(sk, DCCP_CLOSED);
952 } else if (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime) {
953 /* Check zero linger _after_ checking for unread data. */
954 sk->sk_prot->disconnect(sk, 0);
955 } else if (sk->sk_state != DCCP_CLOSED) {
956 dccp_terminate_connection(sk);
959 sk_stream_wait_close(sk, timeout);
961 adjudge_to_death:
962 state = sk->sk_state;
963 sock_hold(sk);
964 sock_orphan(sk);
967 * It is the last release_sock in its life. It will remove backlog.
969 release_sock(sk);
971 * Now socket is owned by kernel and we acquire BH lock
972 * to finish close. No need to check for user refs.
974 local_bh_disable();
975 bh_lock_sock(sk);
976 WARN_ON(sock_owned_by_user(sk));
978 percpu_counter_inc(sk->sk_prot->orphan_count);
980 /* Have we already been destroyed by a softirq or backlog? */
981 if (state != DCCP_CLOSED && sk->sk_state == DCCP_CLOSED)
982 goto out;
984 if (sk->sk_state == DCCP_CLOSED)
985 inet_csk_destroy_sock(sk);
987 /* Otherwise, socket is reprieved until protocol close. */
989 out:
990 bh_unlock_sock(sk);
991 local_bh_enable();
992 sock_put(sk);
995 EXPORT_SYMBOL_GPL(dccp_close);
997 void dccp_shutdown(struct sock *sk, int how)
999 dccp_pr_debug("called shutdown(%x)\n", how);
1002 EXPORT_SYMBOL_GPL(dccp_shutdown);
1004 static inline int dccp_mib_init(void)
1006 return snmp_mib_init((void**)dccp_statistics, sizeof(struct dccp_mib));
1009 static inline void dccp_mib_exit(void)
1011 snmp_mib_free((void**)dccp_statistics);
1014 static int thash_entries;
1015 module_param(thash_entries, int, 0444);
1016 MODULE_PARM_DESC(thash_entries, "Number of ehash buckets");
1018 #ifdef CONFIG_IP_DCCP_DEBUG
1019 int dccp_debug;
1020 module_param(dccp_debug, bool, 0644);
1021 MODULE_PARM_DESC(dccp_debug, "Enable debug messages");
1023 EXPORT_SYMBOL_GPL(dccp_debug);
1024 #endif
1026 static int __init dccp_init(void)
1028 unsigned long goal;
1029 int ehash_order, bhash_order, i;
1030 int rc;
1032 BUILD_BUG_ON(sizeof(struct dccp_skb_cb) >
1033 FIELD_SIZEOF(struct sk_buff, cb));
1034 rc = percpu_counter_init(&dccp_orphan_count, 0);
1035 if (rc)
1036 goto out;
1037 rc = -ENOBUFS;
1038 inet_hashinfo_init(&dccp_hashinfo);
1039 dccp_hashinfo.bind_bucket_cachep =
1040 kmem_cache_create("dccp_bind_bucket",
1041 sizeof(struct inet_bind_bucket), 0,
1042 SLAB_HWCACHE_ALIGN, NULL);
1043 if (!dccp_hashinfo.bind_bucket_cachep)
1044 goto out_free_percpu;
1047 * Size and allocate the main established and bind bucket
1048 * hash tables.
1050 * The methodology is similar to that of the buffer cache.
1052 if (totalram_pages >= (128 * 1024))
1053 goal = totalram_pages >> (21 - PAGE_SHIFT);
1054 else
1055 goal = totalram_pages >> (23 - PAGE_SHIFT);
1057 if (thash_entries)
1058 goal = (thash_entries *
1059 sizeof(struct inet_ehash_bucket)) >> PAGE_SHIFT;
1060 for (ehash_order = 0; (1UL << ehash_order) < goal; ehash_order++)
1062 do {
1063 dccp_hashinfo.ehash_size = (1UL << ehash_order) * PAGE_SIZE /
1064 sizeof(struct inet_ehash_bucket);
1065 while (dccp_hashinfo.ehash_size &
1066 (dccp_hashinfo.ehash_size - 1))
1067 dccp_hashinfo.ehash_size--;
1068 dccp_hashinfo.ehash = (struct inet_ehash_bucket *)
1069 __get_free_pages(GFP_ATOMIC|__GFP_NOWARN, ehash_order);
1070 } while (!dccp_hashinfo.ehash && --ehash_order > 0);
1072 if (!dccp_hashinfo.ehash) {
1073 DCCP_CRIT("Failed to allocate DCCP established hash table");
1074 goto out_free_bind_bucket_cachep;
1077 for (i = 0; i < dccp_hashinfo.ehash_size; i++) {
1078 INIT_HLIST_NULLS_HEAD(&dccp_hashinfo.ehash[i].chain, i);
1079 INIT_HLIST_NULLS_HEAD(&dccp_hashinfo.ehash[i].twchain, i);
1082 if (inet_ehash_locks_alloc(&dccp_hashinfo))
1083 goto out_free_dccp_ehash;
1085 bhash_order = ehash_order;
1087 do {
1088 dccp_hashinfo.bhash_size = (1UL << bhash_order) * PAGE_SIZE /
1089 sizeof(struct inet_bind_hashbucket);
1090 if ((dccp_hashinfo.bhash_size > (64 * 1024)) &&
1091 bhash_order > 0)
1092 continue;
1093 dccp_hashinfo.bhash = (struct inet_bind_hashbucket *)
1094 __get_free_pages(GFP_ATOMIC|__GFP_NOWARN, bhash_order);
1095 } while (!dccp_hashinfo.bhash && --bhash_order >= 0);
1097 if (!dccp_hashinfo.bhash) {
1098 DCCP_CRIT("Failed to allocate DCCP bind hash table");
1099 goto out_free_dccp_locks;
1102 for (i = 0; i < dccp_hashinfo.bhash_size; i++) {
1103 spin_lock_init(&dccp_hashinfo.bhash[i].lock);
1104 INIT_HLIST_HEAD(&dccp_hashinfo.bhash[i].chain);
1107 rc = dccp_mib_init();
1108 if (rc)
1109 goto out_free_dccp_bhash;
1111 rc = dccp_ackvec_init();
1112 if (rc)
1113 goto out_free_dccp_mib;
1115 rc = dccp_sysctl_init();
1116 if (rc)
1117 goto out_ackvec_exit;
1119 rc = ccid_initialize_builtins();
1120 if (rc)
1121 goto out_sysctl_exit;
1123 dccp_timestamping_init();
1124 out:
1125 return rc;
1126 out_sysctl_exit:
1127 dccp_sysctl_exit();
1128 out_ackvec_exit:
1129 dccp_ackvec_exit();
1130 out_free_dccp_mib:
1131 dccp_mib_exit();
1132 out_free_dccp_bhash:
1133 free_pages((unsigned long)dccp_hashinfo.bhash, bhash_order);
1134 dccp_hashinfo.bhash = NULL;
1135 out_free_dccp_locks:
1136 inet_ehash_locks_free(&dccp_hashinfo);
1137 out_free_dccp_ehash:
1138 free_pages((unsigned long)dccp_hashinfo.ehash, ehash_order);
1139 dccp_hashinfo.ehash = NULL;
1140 out_free_bind_bucket_cachep:
1141 kmem_cache_destroy(dccp_hashinfo.bind_bucket_cachep);
1142 dccp_hashinfo.bind_bucket_cachep = NULL;
1143 out_free_percpu:
1144 percpu_counter_destroy(&dccp_orphan_count);
1145 goto out;
1148 static void __exit dccp_fini(void)
1150 ccid_cleanup_builtins();
1151 dccp_mib_exit();
1152 free_pages((unsigned long)dccp_hashinfo.bhash,
1153 get_order(dccp_hashinfo.bhash_size *
1154 sizeof(struct inet_bind_hashbucket)));
1155 free_pages((unsigned long)dccp_hashinfo.ehash,
1156 get_order(dccp_hashinfo.ehash_size *
1157 sizeof(struct inet_ehash_bucket)));
1158 inet_ehash_locks_free(&dccp_hashinfo);
1159 kmem_cache_destroy(dccp_hashinfo.bind_bucket_cachep);
1160 dccp_ackvec_exit();
1161 dccp_sysctl_exit();
1162 percpu_counter_destroy(&dccp_orphan_count);
1165 module_init(dccp_init);
1166 module_exit(dccp_fini);
1168 MODULE_LICENSE("GPL");
1169 MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@conectiva.com.br>");
1170 MODULE_DESCRIPTION("DCCP - Datagram Congestion Controlled Protocol");