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Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
[mirror_ubuntu-jammy-kernel.git] / net / dccp / proto.c
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 <linux/slab.h>
24 #include <net/checksum.h>
25
26 #include <net/inet_sock.h>
27 #include <net/inet_common.h>
28 #include <net/sock.h>
29 #include <net/xfrm.h>
30
31 #include <asm/ioctls.h>
32 #include <linux/spinlock.h>
33 #include <linux/timer.h>
34 #include <linux/delay.h>
35 #include <linux/poll.h>
36
37 #include "ccid.h"
38 #include "dccp.h"
39 #include "feat.h"
40
41 DEFINE_SNMP_STAT(struct dccp_mib, dccp_statistics) __read_mostly;
42
43 EXPORT_SYMBOL_GPL(dccp_statistics);
44
45 struct percpu_counter dccp_orphan_count;
46 EXPORT_SYMBOL_GPL(dccp_orphan_count);
47
48 struct inet_hashinfo dccp_hashinfo;
49 EXPORT_SYMBOL_GPL(dccp_hashinfo);
50
51 /* the maximum queue length for tx in packets. 0 is no limit */
52 int sysctl_dccp_tx_qlen __read_mostly = 5;
53
54 #ifdef CONFIG_IP_DCCP_DEBUG
55 static const char *dccp_state_name(const int state)
56 {
57 static const char *const dccp_state_names[] = {
58 [DCCP_OPEN] = "OPEN",
59 [DCCP_REQUESTING] = "REQUESTING",
60 [DCCP_PARTOPEN] = "PARTOPEN",
61 [DCCP_LISTEN] = "LISTEN",
62 [DCCP_RESPOND] = "RESPOND",
63 [DCCP_CLOSING] = "CLOSING",
64 [DCCP_ACTIVE_CLOSEREQ] = "CLOSEREQ",
65 [DCCP_PASSIVE_CLOSE] = "PASSIVE_CLOSE",
66 [DCCP_PASSIVE_CLOSEREQ] = "PASSIVE_CLOSEREQ",
67 [DCCP_TIME_WAIT] = "TIME_WAIT",
68 [DCCP_CLOSED] = "CLOSED",
69 };
70
71 if (state >= DCCP_MAX_STATES)
72 return "INVALID STATE!";
73 else
74 return dccp_state_names[state];
75 }
76 #endif
77
78 void dccp_set_state(struct sock *sk, const int state)
79 {
80 const int oldstate = sk->sk_state;
81
82 dccp_pr_debug("%s(%p) %s --> %s\n", dccp_role(sk), sk,
83 dccp_state_name(oldstate), dccp_state_name(state));
84 WARN_ON(state == oldstate);
85
86 switch (state) {
87 case DCCP_OPEN:
88 if (oldstate != DCCP_OPEN)
89 DCCP_INC_STATS(DCCP_MIB_CURRESTAB);
90 /* Client retransmits all Confirm options until entering OPEN */
91 if (oldstate == DCCP_PARTOPEN)
92 dccp_feat_list_purge(&dccp_sk(sk)->dccps_featneg);
93 break;
94
95 case DCCP_CLOSED:
96 if (oldstate == DCCP_OPEN || oldstate == DCCP_ACTIVE_CLOSEREQ ||
97 oldstate == DCCP_CLOSING)
98 DCCP_INC_STATS(DCCP_MIB_ESTABRESETS);
99
100 sk->sk_prot->unhash(sk);
101 if (inet_csk(sk)->icsk_bind_hash != NULL &&
102 !(sk->sk_userlocks & SOCK_BINDPORT_LOCK))
103 inet_put_port(sk);
104 /* fall through */
105 default:
106 if (oldstate == DCCP_OPEN)
107 DCCP_DEC_STATS(DCCP_MIB_CURRESTAB);
108 }
109
110 /* Change state AFTER socket is unhashed to avoid closed
111 * socket sitting in hash tables.
112 */
113 sk->sk_state = state;
114 }
115
116 EXPORT_SYMBOL_GPL(dccp_set_state);
117
118 static void dccp_finish_passive_close(struct sock *sk)
119 {
120 switch (sk->sk_state) {
121 case DCCP_PASSIVE_CLOSE:
122 /* Node (client or server) has received Close packet. */
123 dccp_send_reset(sk, DCCP_RESET_CODE_CLOSED);
124 dccp_set_state(sk, DCCP_CLOSED);
125 break;
126 case DCCP_PASSIVE_CLOSEREQ:
127 /*
128 * Client received CloseReq. We set the `active' flag so that
129 * dccp_send_close() retransmits the Close as per RFC 4340, 8.3.
130 */
131 dccp_send_close(sk, 1);
132 dccp_set_state(sk, DCCP_CLOSING);
133 }
134 }
135
136 void dccp_done(struct sock *sk)
137 {
138 dccp_set_state(sk, DCCP_CLOSED);
139 dccp_clear_xmit_timers(sk);
140
141 sk->sk_shutdown = SHUTDOWN_MASK;
142
143 if (!sock_flag(sk, SOCK_DEAD))
144 sk->sk_state_change(sk);
145 else
146 inet_csk_destroy_sock(sk);
147 }
148
149 EXPORT_SYMBOL_GPL(dccp_done);
150
151 const char *dccp_packet_name(const int type)
152 {
153 static const char *const dccp_packet_names[] = {
154 [DCCP_PKT_REQUEST] = "REQUEST",
155 [DCCP_PKT_RESPONSE] = "RESPONSE",
156 [DCCP_PKT_DATA] = "DATA",
157 [DCCP_PKT_ACK] = "ACK",
158 [DCCP_PKT_DATAACK] = "DATAACK",
159 [DCCP_PKT_CLOSEREQ] = "CLOSEREQ",
160 [DCCP_PKT_CLOSE] = "CLOSE",
161 [DCCP_PKT_RESET] = "RESET",
162 [DCCP_PKT_SYNC] = "SYNC",
163 [DCCP_PKT_SYNCACK] = "SYNCACK",
164 };
165
166 if (type >= DCCP_NR_PKT_TYPES)
167 return "INVALID";
168 else
169 return dccp_packet_names[type];
170 }
171
172 EXPORT_SYMBOL_GPL(dccp_packet_name);
173
174 static void dccp_sk_destruct(struct sock *sk)
175 {
176 struct dccp_sock *dp = dccp_sk(sk);
177
178 ccid_hc_tx_delete(dp->dccps_hc_tx_ccid, sk);
179 dp->dccps_hc_tx_ccid = NULL;
180 inet_sock_destruct(sk);
181 }
182
183 int dccp_init_sock(struct sock *sk, const __u8 ctl_sock_initialized)
184 {
185 struct dccp_sock *dp = dccp_sk(sk);
186 struct inet_connection_sock *icsk = inet_csk(sk);
187
188 icsk->icsk_rto = DCCP_TIMEOUT_INIT;
189 icsk->icsk_syn_retries = sysctl_dccp_request_retries;
190 sk->sk_state = DCCP_CLOSED;
191 sk->sk_write_space = dccp_write_space;
192 sk->sk_destruct = dccp_sk_destruct;
193 icsk->icsk_sync_mss = dccp_sync_mss;
194 dp->dccps_mss_cache = 536;
195 dp->dccps_rate_last = jiffies;
196 dp->dccps_role = DCCP_ROLE_UNDEFINED;
197 dp->dccps_service = DCCP_SERVICE_CODE_IS_ABSENT;
198 dp->dccps_tx_qlen = sysctl_dccp_tx_qlen;
199
200 dccp_init_xmit_timers(sk);
201
202 INIT_LIST_HEAD(&dp->dccps_featneg);
203 /* control socket doesn't need feat nego */
204 if (likely(ctl_sock_initialized))
205 return dccp_feat_init(sk);
206 return 0;
207 }
208
209 EXPORT_SYMBOL_GPL(dccp_init_sock);
210
211 void dccp_destroy_sock(struct sock *sk)
212 {
213 struct dccp_sock *dp = dccp_sk(sk);
214
215 __skb_queue_purge(&sk->sk_write_queue);
216 if (sk->sk_send_head != NULL) {
217 kfree_skb(sk->sk_send_head);
218 sk->sk_send_head = NULL;
219 }
220
221 /* Clean up a referenced DCCP bind bucket. */
222 if (inet_csk(sk)->icsk_bind_hash != NULL)
223 inet_put_port(sk);
224
225 kfree(dp->dccps_service_list);
226 dp->dccps_service_list = NULL;
227
228 if (dp->dccps_hc_rx_ackvec != NULL) {
229 dccp_ackvec_free(dp->dccps_hc_rx_ackvec);
230 dp->dccps_hc_rx_ackvec = NULL;
231 }
232 ccid_hc_rx_delete(dp->dccps_hc_rx_ccid, sk);
233 dp->dccps_hc_rx_ccid = NULL;
234
235 /* clean up feature negotiation state */
236 dccp_feat_list_purge(&dp->dccps_featneg);
237 }
238
239 EXPORT_SYMBOL_GPL(dccp_destroy_sock);
240
241 static inline int dccp_listen_start(struct sock *sk, int backlog)
242 {
243 struct dccp_sock *dp = dccp_sk(sk);
244
245 dp->dccps_role = DCCP_ROLE_LISTEN;
246 /* do not start to listen if feature negotiation setup fails */
247 if (dccp_feat_finalise_settings(dp))
248 return -EPROTO;
249 return inet_csk_listen_start(sk, backlog);
250 }
251
252 static inline int dccp_need_reset(int state)
253 {
254 return state != DCCP_CLOSED && state != DCCP_LISTEN &&
255 state != DCCP_REQUESTING;
256 }
257
258 int dccp_disconnect(struct sock *sk, int flags)
259 {
260 struct inet_connection_sock *icsk = inet_csk(sk);
261 struct inet_sock *inet = inet_sk(sk);
262 struct dccp_sock *dp = dccp_sk(sk);
263 int err = 0;
264 const int old_state = sk->sk_state;
265
266 if (old_state != DCCP_CLOSED)
267 dccp_set_state(sk, DCCP_CLOSED);
268
269 /*
270 * This corresponds to the ABORT function of RFC793, sec. 3.8
271 * TCP uses a RST segment, DCCP a Reset packet with Code 2, "Aborted".
272 */
273 if (old_state == DCCP_LISTEN) {
274 inet_csk_listen_stop(sk);
275 } else if (dccp_need_reset(old_state)) {
276 dccp_send_reset(sk, DCCP_RESET_CODE_ABORTED);
277 sk->sk_err = ECONNRESET;
278 } else if (old_state == DCCP_REQUESTING)
279 sk->sk_err = ECONNRESET;
280
281 dccp_clear_xmit_timers(sk);
282 ccid_hc_rx_delete(dp->dccps_hc_rx_ccid, sk);
283 ccid_hc_tx_delete(dp->dccps_hc_tx_ccid, sk);
284 dp->dccps_hc_rx_ccid = NULL;
285 dp->dccps_hc_tx_ccid = NULL;
286
287 __skb_queue_purge(&sk->sk_receive_queue);
288 __skb_queue_purge(&sk->sk_write_queue);
289 if (sk->sk_send_head != NULL) {
290 __kfree_skb(sk->sk_send_head);
291 sk->sk_send_head = NULL;
292 }
293
294 inet->inet_dport = 0;
295
296 if (!(sk->sk_userlocks & SOCK_BINDADDR_LOCK))
297 inet_reset_saddr(sk);
298
299 sk->sk_shutdown = 0;
300 sock_reset_flag(sk, SOCK_DONE);
301
302 icsk->icsk_backoff = 0;
303 inet_csk_delack_init(sk);
304 __sk_dst_reset(sk);
305
306 WARN_ON(inet->inet_num && !icsk->icsk_bind_hash);
307
308 sk->sk_error_report(sk);
309 return err;
310 }
311
312 EXPORT_SYMBOL_GPL(dccp_disconnect);
313
314 /*
315 * Wait for a DCCP event.
316 *
317 * Note that we don't need to lock the socket, as the upper poll layers
318 * take care of normal races (between the test and the event) and we don't
319 * go look at any of the socket buffers directly.
320 */
321 __poll_t dccp_poll(struct file *file, struct socket *sock,
322 poll_table *wait)
323 {
324 __poll_t mask;
325 struct sock *sk = sock->sk;
326
327 sock_poll_wait(file, sk_sleep(sk), wait);
328 if (sk->sk_state == DCCP_LISTEN)
329 return inet_csk_listen_poll(sk);
330
331 /* Socket is not locked. We are protected from async events
332 by poll logic and correct handling of state changes
333 made by another threads is impossible in any case.
334 */
335
336 mask = 0;
337 if (sk->sk_err)
338 mask = POLLERR;
339
340 if (sk->sk_shutdown == SHUTDOWN_MASK || sk->sk_state == DCCP_CLOSED)
341 mask |= POLLHUP;
342 if (sk->sk_shutdown & RCV_SHUTDOWN)
343 mask |= POLLIN | POLLRDNORM | POLLRDHUP;
344
345 /* Connected? */
346 if ((1 << sk->sk_state) & ~(DCCPF_REQUESTING | DCCPF_RESPOND)) {
347 if (atomic_read(&sk->sk_rmem_alloc) > 0)
348 mask |= POLLIN | POLLRDNORM;
349
350 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
351 if (sk_stream_is_writeable(sk)) {
352 mask |= POLLOUT | POLLWRNORM;
353 } else { /* send SIGIO later */
354 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
355 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
356
357 /* Race breaker. If space is freed after
358 * wspace test but before the flags are set,
359 * IO signal will be lost.
360 */
361 if (sk_stream_is_writeable(sk))
362 mask |= POLLOUT | POLLWRNORM;
363 }
364 }
365 }
366 return mask;
367 }
368
369 EXPORT_SYMBOL_GPL(dccp_poll);
370
371 int dccp_ioctl(struct sock *sk, int cmd, unsigned long arg)
372 {
373 int rc = -ENOTCONN;
374
375 lock_sock(sk);
376
377 if (sk->sk_state == DCCP_LISTEN)
378 goto out;
379
380 switch (cmd) {
381 case SIOCINQ: {
382 struct sk_buff *skb;
383 unsigned long amount = 0;
384
385 skb = skb_peek(&sk->sk_receive_queue);
386 if (skb != NULL) {
387 /*
388 * We will only return the amount of this packet since
389 * that is all that will be read.
390 */
391 amount = skb->len;
392 }
393 rc = put_user(amount, (int __user *)arg);
394 }
395 break;
396 default:
397 rc = -ENOIOCTLCMD;
398 break;
399 }
400 out:
401 release_sock(sk);
402 return rc;
403 }
404
405 EXPORT_SYMBOL_GPL(dccp_ioctl);
406
407 static int dccp_setsockopt_service(struct sock *sk, const __be32 service,
408 char __user *optval, unsigned int optlen)
409 {
410 struct dccp_sock *dp = dccp_sk(sk);
411 struct dccp_service_list *sl = NULL;
412
413 if (service == DCCP_SERVICE_INVALID_VALUE ||
414 optlen > DCCP_SERVICE_LIST_MAX_LEN * sizeof(u32))
415 return -EINVAL;
416
417 if (optlen > sizeof(service)) {
418 sl = kmalloc(optlen, GFP_KERNEL);
419 if (sl == NULL)
420 return -ENOMEM;
421
422 sl->dccpsl_nr = optlen / sizeof(u32) - 1;
423 if (copy_from_user(sl->dccpsl_list,
424 optval + sizeof(service),
425 optlen - sizeof(service)) ||
426 dccp_list_has_service(sl, DCCP_SERVICE_INVALID_VALUE)) {
427 kfree(sl);
428 return -EFAULT;
429 }
430 }
431
432 lock_sock(sk);
433 dp->dccps_service = service;
434
435 kfree(dp->dccps_service_list);
436
437 dp->dccps_service_list = sl;
438 release_sock(sk);
439 return 0;
440 }
441
442 static int dccp_setsockopt_cscov(struct sock *sk, int cscov, bool rx)
443 {
444 u8 *list, len;
445 int i, rc;
446
447 if (cscov < 0 || cscov > 15)
448 return -EINVAL;
449 /*
450 * Populate a list of permissible values, in the range cscov...15. This
451 * is necessary since feature negotiation of single values only works if
452 * both sides incidentally choose the same value. Since the list starts
453 * lowest-value first, negotiation will pick the smallest shared value.
454 */
455 if (cscov == 0)
456 return 0;
457 len = 16 - cscov;
458
459 list = kmalloc(len, GFP_KERNEL);
460 if (list == NULL)
461 return -ENOBUFS;
462
463 for (i = 0; i < len; i++)
464 list[i] = cscov++;
465
466 rc = dccp_feat_register_sp(sk, DCCPF_MIN_CSUM_COVER, rx, list, len);
467
468 if (rc == 0) {
469 if (rx)
470 dccp_sk(sk)->dccps_pcrlen = cscov;
471 else
472 dccp_sk(sk)->dccps_pcslen = cscov;
473 }
474 kfree(list);
475 return rc;
476 }
477
478 static int dccp_setsockopt_ccid(struct sock *sk, int type,
479 char __user *optval, unsigned int optlen)
480 {
481 u8 *val;
482 int rc = 0;
483
484 if (optlen < 1 || optlen > DCCP_FEAT_MAX_SP_VALS)
485 return -EINVAL;
486
487 val = memdup_user(optval, optlen);
488 if (IS_ERR(val))
489 return PTR_ERR(val);
490
491 lock_sock(sk);
492 if (type == DCCP_SOCKOPT_TX_CCID || type == DCCP_SOCKOPT_CCID)
493 rc = dccp_feat_register_sp(sk, DCCPF_CCID, 1, val, optlen);
494
495 if (!rc && (type == DCCP_SOCKOPT_RX_CCID || type == DCCP_SOCKOPT_CCID))
496 rc = dccp_feat_register_sp(sk, DCCPF_CCID, 0, val, optlen);
497 release_sock(sk);
498
499 kfree(val);
500 return rc;
501 }
502
503 static int do_dccp_setsockopt(struct sock *sk, int level, int optname,
504 char __user *optval, unsigned int optlen)
505 {
506 struct dccp_sock *dp = dccp_sk(sk);
507 int val, err = 0;
508
509 switch (optname) {
510 case DCCP_SOCKOPT_PACKET_SIZE:
511 DCCP_WARN("sockopt(PACKET_SIZE) is deprecated: fix your app\n");
512 return 0;
513 case DCCP_SOCKOPT_CHANGE_L:
514 case DCCP_SOCKOPT_CHANGE_R:
515 DCCP_WARN("sockopt(CHANGE_L/R) is deprecated: fix your app\n");
516 return 0;
517 case DCCP_SOCKOPT_CCID:
518 case DCCP_SOCKOPT_RX_CCID:
519 case DCCP_SOCKOPT_TX_CCID:
520 return dccp_setsockopt_ccid(sk, optname, optval, optlen);
521 }
522
523 if (optlen < (int)sizeof(int))
524 return -EINVAL;
525
526 if (get_user(val, (int __user *)optval))
527 return -EFAULT;
528
529 if (optname == DCCP_SOCKOPT_SERVICE)
530 return dccp_setsockopt_service(sk, val, optval, optlen);
531
532 lock_sock(sk);
533 switch (optname) {
534 case DCCP_SOCKOPT_SERVER_TIMEWAIT:
535 if (dp->dccps_role != DCCP_ROLE_SERVER)
536 err = -EOPNOTSUPP;
537 else
538 dp->dccps_server_timewait = (val != 0);
539 break;
540 case DCCP_SOCKOPT_SEND_CSCOV:
541 err = dccp_setsockopt_cscov(sk, val, false);
542 break;
543 case DCCP_SOCKOPT_RECV_CSCOV:
544 err = dccp_setsockopt_cscov(sk, val, true);
545 break;
546 case DCCP_SOCKOPT_QPOLICY_ID:
547 if (sk->sk_state != DCCP_CLOSED)
548 err = -EISCONN;
549 else if (val < 0 || val >= DCCPQ_POLICY_MAX)
550 err = -EINVAL;
551 else
552 dp->dccps_qpolicy = val;
553 break;
554 case DCCP_SOCKOPT_QPOLICY_TXQLEN:
555 if (val < 0)
556 err = -EINVAL;
557 else
558 dp->dccps_tx_qlen = val;
559 break;
560 default:
561 err = -ENOPROTOOPT;
562 break;
563 }
564 release_sock(sk);
565
566 return err;
567 }
568
569 int dccp_setsockopt(struct sock *sk, int level, int optname,
570 char __user *optval, unsigned int optlen)
571 {
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);
577 }
578
579 EXPORT_SYMBOL_GPL(dccp_setsockopt);
580
581 #ifdef CONFIG_COMPAT
582 int compat_dccp_setsockopt(struct sock *sk, int level, int optname,
583 char __user *optval, unsigned int optlen)
584 {
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);
589 }
590
591 EXPORT_SYMBOL_GPL(compat_dccp_setsockopt);
592 #endif
593
594 static int dccp_getsockopt_service(struct sock *sk, int len,
595 __be32 __user *optval,
596 int __user *optlen)
597 {
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);
601
602 lock_sock(sk);
603 if ((sl = dp->dccps_service_list) != NULL) {
604 slen = sl->dccpsl_nr * sizeof(u32);
605 total_len += slen;
606 }
607
608 err = -EINVAL;
609 if (total_len > len)
610 goto out;
611
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;
620 }
621
622 static int do_dccp_getsockopt(struct sock *sk, int level, int optname,
623 char __user *optval, int __user *optlen)
624 {
625 struct dccp_sock *dp;
626 int val, len;
627
628 if (get_user(len, optlen))
629 return -EFAULT;
630
631 if (len < (int)sizeof(int))
632 return -EINVAL;
633
634 dp = dccp_sk(sk);
635
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_AVAILABLE_CCIDS:
647 return ccid_getsockopt_builtin_ccids(sk, len, optval, optlen);
648 case DCCP_SOCKOPT_TX_CCID:
649 val = ccid_get_current_tx_ccid(dp);
650 if (val < 0)
651 return -ENOPROTOOPT;
652 break;
653 case DCCP_SOCKOPT_RX_CCID:
654 val = ccid_get_current_rx_ccid(dp);
655 if (val < 0)
656 return -ENOPROTOOPT;
657 break;
658 case DCCP_SOCKOPT_SERVER_TIMEWAIT:
659 val = dp->dccps_server_timewait;
660 break;
661 case DCCP_SOCKOPT_SEND_CSCOV:
662 val = dp->dccps_pcslen;
663 break;
664 case DCCP_SOCKOPT_RECV_CSCOV:
665 val = dp->dccps_pcrlen;
666 break;
667 case DCCP_SOCKOPT_QPOLICY_ID:
668 val = dp->dccps_qpolicy;
669 break;
670 case DCCP_SOCKOPT_QPOLICY_TXQLEN:
671 val = dp->dccps_tx_qlen;
672 break;
673 case 128 ... 191:
674 return ccid_hc_rx_getsockopt(dp->dccps_hc_rx_ccid, sk, optname,
675 len, (u32 __user *)optval, optlen);
676 case 192 ... 255:
677 return ccid_hc_tx_getsockopt(dp->dccps_hc_tx_ccid, sk, optname,
678 len, (u32 __user *)optval, optlen);
679 default:
680 return -ENOPROTOOPT;
681 }
682
683 len = sizeof(val);
684 if (put_user(len, optlen) || copy_to_user(optval, &val, len))
685 return -EFAULT;
686
687 return 0;
688 }
689
690 int dccp_getsockopt(struct sock *sk, int level, int optname,
691 char __user *optval, int __user *optlen)
692 {
693 if (level != SOL_DCCP)
694 return inet_csk(sk)->icsk_af_ops->getsockopt(sk, level,
695 optname, optval,
696 optlen);
697 return do_dccp_getsockopt(sk, level, optname, optval, optlen);
698 }
699
700 EXPORT_SYMBOL_GPL(dccp_getsockopt);
701
702 #ifdef CONFIG_COMPAT
703 int compat_dccp_getsockopt(struct sock *sk, int level, int optname,
704 char __user *optval, int __user *optlen)
705 {
706 if (level != SOL_DCCP)
707 return inet_csk_compat_getsockopt(sk, level, optname,
708 optval, optlen);
709 return do_dccp_getsockopt(sk, level, optname, optval, optlen);
710 }
711
712 EXPORT_SYMBOL_GPL(compat_dccp_getsockopt);
713 #endif
714
715 static int dccp_msghdr_parse(struct msghdr *msg, struct sk_buff *skb)
716 {
717 struct cmsghdr *cmsg;
718
719 /*
720 * Assign an (opaque) qpolicy priority value to skb->priority.
721 *
722 * We are overloading this skb field for use with the qpolicy subystem.
723 * The skb->priority is normally used for the SO_PRIORITY option, which
724 * is initialised from sk_priority. Since the assignment of sk_priority
725 * to skb->priority happens later (on layer 3), we overload this field
726 * for use with queueing priorities as long as the skb is on layer 4.
727 * The default priority value (if nothing is set) is 0.
728 */
729 skb->priority = 0;
730
731 for_each_cmsghdr(cmsg, msg) {
732 if (!CMSG_OK(msg, cmsg))
733 return -EINVAL;
734
735 if (cmsg->cmsg_level != SOL_DCCP)
736 continue;
737
738 if (cmsg->cmsg_type <= DCCP_SCM_QPOLICY_MAX &&
739 !dccp_qpolicy_param_ok(skb->sk, cmsg->cmsg_type))
740 return -EINVAL;
741
742 switch (cmsg->cmsg_type) {
743 case DCCP_SCM_PRIORITY:
744 if (cmsg->cmsg_len != CMSG_LEN(sizeof(__u32)))
745 return -EINVAL;
746 skb->priority = *(__u32 *)CMSG_DATA(cmsg);
747 break;
748 default:
749 return -EINVAL;
750 }
751 }
752 return 0;
753 }
754
755 int dccp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
756 {
757 const struct dccp_sock *dp = dccp_sk(sk);
758 const int flags = msg->msg_flags;
759 const int noblock = flags & MSG_DONTWAIT;
760 struct sk_buff *skb;
761 int rc, size;
762 long timeo;
763
764 if (len > dp->dccps_mss_cache)
765 return -EMSGSIZE;
766
767 lock_sock(sk);
768
769 if (dccp_qpolicy_full(sk)) {
770 rc = -EAGAIN;
771 goto out_release;
772 }
773
774 timeo = sock_sndtimeo(sk, noblock);
775
776 /*
777 * We have to use sk_stream_wait_connect here to set sk_write_pending,
778 * so that the trick in dccp_rcv_request_sent_state_process.
779 */
780 /* Wait for a connection to finish. */
781 if ((1 << sk->sk_state) & ~(DCCPF_OPEN | DCCPF_PARTOPEN))
782 if ((rc = sk_stream_wait_connect(sk, &timeo)) != 0)
783 goto out_release;
784
785 size = sk->sk_prot->max_header + len;
786 release_sock(sk);
787 skb = sock_alloc_send_skb(sk, size, noblock, &rc);
788 lock_sock(sk);
789 if (skb == NULL)
790 goto out_release;
791
792 skb_reserve(skb, sk->sk_prot->max_header);
793 rc = memcpy_from_msg(skb_put(skb, len), msg, len);
794 if (rc != 0)
795 goto out_discard;
796
797 rc = dccp_msghdr_parse(msg, skb);
798 if (rc != 0)
799 goto out_discard;
800
801 dccp_qpolicy_push(sk, skb);
802 /*
803 * The xmit_timer is set if the TX CCID is rate-based and will expire
804 * when congestion control permits to release further packets into the
805 * network. Window-based CCIDs do not use this timer.
806 */
807 if (!timer_pending(&dp->dccps_xmit_timer))
808 dccp_write_xmit(sk);
809 out_release:
810 release_sock(sk);
811 return rc ? : len;
812 out_discard:
813 kfree_skb(skb);
814 goto out_release;
815 }
816
817 EXPORT_SYMBOL_GPL(dccp_sendmsg);
818
819 int dccp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int nonblock,
820 int flags, int *addr_len)
821 {
822 const struct dccp_hdr *dh;
823 long timeo;
824
825 lock_sock(sk);
826
827 if (sk->sk_state == DCCP_LISTEN) {
828 len = -ENOTCONN;
829 goto out;
830 }
831
832 timeo = sock_rcvtimeo(sk, nonblock);
833
834 do {
835 struct sk_buff *skb = skb_peek(&sk->sk_receive_queue);
836
837 if (skb == NULL)
838 goto verify_sock_status;
839
840 dh = dccp_hdr(skb);
841
842 switch (dh->dccph_type) {
843 case DCCP_PKT_DATA:
844 case DCCP_PKT_DATAACK:
845 goto found_ok_skb;
846
847 case DCCP_PKT_CLOSE:
848 case DCCP_PKT_CLOSEREQ:
849 if (!(flags & MSG_PEEK))
850 dccp_finish_passive_close(sk);
851 /* fall through */
852 case DCCP_PKT_RESET:
853 dccp_pr_debug("found fin (%s) ok!\n",
854 dccp_packet_name(dh->dccph_type));
855 len = 0;
856 goto found_fin_ok;
857 default:
858 dccp_pr_debug("packet_type=%s\n",
859 dccp_packet_name(dh->dccph_type));
860 sk_eat_skb(sk, skb);
861 }
862 verify_sock_status:
863 if (sock_flag(sk, SOCK_DONE)) {
864 len = 0;
865 break;
866 }
867
868 if (sk->sk_err) {
869 len = sock_error(sk);
870 break;
871 }
872
873 if (sk->sk_shutdown & RCV_SHUTDOWN) {
874 len = 0;
875 break;
876 }
877
878 if (sk->sk_state == DCCP_CLOSED) {
879 if (!sock_flag(sk, SOCK_DONE)) {
880 /* This occurs when user tries to read
881 * from never connected socket.
882 */
883 len = -ENOTCONN;
884 break;
885 }
886 len = 0;
887 break;
888 }
889
890 if (!timeo) {
891 len = -EAGAIN;
892 break;
893 }
894
895 if (signal_pending(current)) {
896 len = sock_intr_errno(timeo);
897 break;
898 }
899
900 sk_wait_data(sk, &timeo, NULL);
901 continue;
902 found_ok_skb:
903 if (len > skb->len)
904 len = skb->len;
905 else if (len < skb->len)
906 msg->msg_flags |= MSG_TRUNC;
907
908 if (skb_copy_datagram_msg(skb, 0, msg, len)) {
909 /* Exception. Bailout! */
910 len = -EFAULT;
911 break;
912 }
913 if (flags & MSG_TRUNC)
914 len = skb->len;
915 found_fin_ok:
916 if (!(flags & MSG_PEEK))
917 sk_eat_skb(sk, skb);
918 break;
919 } while (1);
920 out:
921 release_sock(sk);
922 return len;
923 }
924
925 EXPORT_SYMBOL_GPL(dccp_recvmsg);
926
927 int inet_dccp_listen(struct socket *sock, int backlog)
928 {
929 struct sock *sk = sock->sk;
930 unsigned char old_state;
931 int err;
932
933 lock_sock(sk);
934
935 err = -EINVAL;
936 if (sock->state != SS_UNCONNECTED || sock->type != SOCK_DCCP)
937 goto out;
938
939 old_state = sk->sk_state;
940 if (!((1 << old_state) & (DCCPF_CLOSED | DCCPF_LISTEN)))
941 goto out;
942
943 /* Really, if the socket is already in listen state
944 * we can only allow the backlog to be adjusted.
945 */
946 if (old_state != DCCP_LISTEN) {
947 /*
948 * FIXME: here it probably should be sk->sk_prot->listen_start
949 * see tcp_listen_start
950 */
951 err = dccp_listen_start(sk, backlog);
952 if (err)
953 goto out;
954 }
955 sk->sk_max_ack_backlog = backlog;
956 err = 0;
957
958 out:
959 release_sock(sk);
960 return err;
961 }
962
963 EXPORT_SYMBOL_GPL(inet_dccp_listen);
964
965 static void dccp_terminate_connection(struct sock *sk)
966 {
967 u8 next_state = DCCP_CLOSED;
968
969 switch (sk->sk_state) {
970 case DCCP_PASSIVE_CLOSE:
971 case DCCP_PASSIVE_CLOSEREQ:
972 dccp_finish_passive_close(sk);
973 break;
974 case DCCP_PARTOPEN:
975 dccp_pr_debug("Stop PARTOPEN timer (%p)\n", sk);
976 inet_csk_clear_xmit_timer(sk, ICSK_TIME_DACK);
977 /* fall through */
978 case DCCP_OPEN:
979 dccp_send_close(sk, 1);
980
981 if (dccp_sk(sk)->dccps_role == DCCP_ROLE_SERVER &&
982 !dccp_sk(sk)->dccps_server_timewait)
983 next_state = DCCP_ACTIVE_CLOSEREQ;
984 else
985 next_state = DCCP_CLOSING;
986 /* fall through */
987 default:
988 dccp_set_state(sk, next_state);
989 }
990 }
991
992 void dccp_close(struct sock *sk, long timeout)
993 {
994 struct dccp_sock *dp = dccp_sk(sk);
995 struct sk_buff *skb;
996 u32 data_was_unread = 0;
997 int state;
998
999 lock_sock(sk);
1000
1001 sk->sk_shutdown = SHUTDOWN_MASK;
1002
1003 if (sk->sk_state == DCCP_LISTEN) {
1004 dccp_set_state(sk, DCCP_CLOSED);
1005
1006 /* Special case. */
1007 inet_csk_listen_stop(sk);
1008
1009 goto adjudge_to_death;
1010 }
1011
1012 sk_stop_timer(sk, &dp->dccps_xmit_timer);
1013
1014 /*
1015 * We need to flush the recv. buffs. We do this only on the
1016 * descriptor close, not protocol-sourced closes, because the
1017 *reader process may not have drained the data yet!
1018 */
1019 while ((skb = __skb_dequeue(&sk->sk_receive_queue)) != NULL) {
1020 data_was_unread += skb->len;
1021 __kfree_skb(skb);
1022 }
1023
1024 /* If socket has been already reset kill it. */
1025 if (sk->sk_state == DCCP_CLOSED)
1026 goto adjudge_to_death;
1027
1028 if (data_was_unread) {
1029 /* Unread data was tossed, send an appropriate Reset Code */
1030 DCCP_WARN("ABORT with %u bytes unread\n", data_was_unread);
1031 dccp_send_reset(sk, DCCP_RESET_CODE_ABORTED);
1032 dccp_set_state(sk, DCCP_CLOSED);
1033 } else if (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime) {
1034 /* Check zero linger _after_ checking for unread data. */
1035 sk->sk_prot->disconnect(sk, 0);
1036 } else if (sk->sk_state != DCCP_CLOSED) {
1037 /*
1038 * Normal connection termination. May need to wait if there are
1039 * still packets in the TX queue that are delayed by the CCID.
1040 */
1041 dccp_flush_write_queue(sk, &timeout);
1042 dccp_terminate_connection(sk);
1043 }
1044
1045 /*
1046 * Flush write queue. This may be necessary in several cases:
1047 * - we have been closed by the peer but still have application data;
1048 * - abortive termination (unread data or zero linger time),
1049 * - normal termination but queue could not be flushed within time limit
1050 */
1051 __skb_queue_purge(&sk->sk_write_queue);
1052
1053 sk_stream_wait_close(sk, timeout);
1054
1055 adjudge_to_death:
1056 state = sk->sk_state;
1057 sock_hold(sk);
1058 sock_orphan(sk);
1059
1060 /*
1061 * It is the last release_sock in its life. It will remove backlog.
1062 */
1063 release_sock(sk);
1064 /*
1065 * Now socket is owned by kernel and we acquire BH lock
1066 * to finish close. No need to check for user refs.
1067 */
1068 local_bh_disable();
1069 bh_lock_sock(sk);
1070 WARN_ON(sock_owned_by_user(sk));
1071
1072 percpu_counter_inc(sk->sk_prot->orphan_count);
1073
1074 /* Have we already been destroyed by a softirq or backlog? */
1075 if (state != DCCP_CLOSED && sk->sk_state == DCCP_CLOSED)
1076 goto out;
1077
1078 if (sk->sk_state == DCCP_CLOSED)
1079 inet_csk_destroy_sock(sk);
1080
1081 /* Otherwise, socket is reprieved until protocol close. */
1082
1083 out:
1084 bh_unlock_sock(sk);
1085 local_bh_enable();
1086 sock_put(sk);
1087 }
1088
1089 EXPORT_SYMBOL_GPL(dccp_close);
1090
1091 void dccp_shutdown(struct sock *sk, int how)
1092 {
1093 dccp_pr_debug("called shutdown(%x)\n", how);
1094 }
1095
1096 EXPORT_SYMBOL_GPL(dccp_shutdown);
1097
1098 static inline int __init dccp_mib_init(void)
1099 {
1100 dccp_statistics = alloc_percpu(struct dccp_mib);
1101 if (!dccp_statistics)
1102 return -ENOMEM;
1103 return 0;
1104 }
1105
1106 static inline void dccp_mib_exit(void)
1107 {
1108 free_percpu(dccp_statistics);
1109 }
1110
1111 static int thash_entries;
1112 module_param(thash_entries, int, 0444);
1113 MODULE_PARM_DESC(thash_entries, "Number of ehash buckets");
1114
1115 #ifdef CONFIG_IP_DCCP_DEBUG
1116 bool dccp_debug;
1117 module_param(dccp_debug, bool, 0644);
1118 MODULE_PARM_DESC(dccp_debug, "Enable debug messages");
1119
1120 EXPORT_SYMBOL_GPL(dccp_debug);
1121 #endif
1122
1123 static int __init dccp_init(void)
1124 {
1125 unsigned long goal;
1126 int ehash_order, bhash_order, i;
1127 int rc;
1128
1129 BUILD_BUG_ON(sizeof(struct dccp_skb_cb) >
1130 FIELD_SIZEOF(struct sk_buff, cb));
1131 rc = percpu_counter_init(&dccp_orphan_count, 0, GFP_KERNEL);
1132 if (rc)
1133 goto out_fail;
1134 rc = -ENOBUFS;
1135 inet_hashinfo_init(&dccp_hashinfo);
1136 dccp_hashinfo.bind_bucket_cachep =
1137 kmem_cache_create("dccp_bind_bucket",
1138 sizeof(struct inet_bind_bucket), 0,
1139 SLAB_HWCACHE_ALIGN, NULL);
1140 if (!dccp_hashinfo.bind_bucket_cachep)
1141 goto out_free_percpu;
1142
1143 /*
1144 * Size and allocate the main established and bind bucket
1145 * hash tables.
1146 *
1147 * The methodology is similar to that of the buffer cache.
1148 */
1149 if (totalram_pages >= (128 * 1024))
1150 goal = totalram_pages >> (21 - PAGE_SHIFT);
1151 else
1152 goal = totalram_pages >> (23 - PAGE_SHIFT);
1153
1154 if (thash_entries)
1155 goal = (thash_entries *
1156 sizeof(struct inet_ehash_bucket)) >> PAGE_SHIFT;
1157 for (ehash_order = 0; (1UL << ehash_order) < goal; ehash_order++)
1158 ;
1159 do {
1160 unsigned long hash_size = (1UL << ehash_order) * PAGE_SIZE /
1161 sizeof(struct inet_ehash_bucket);
1162
1163 while (hash_size & (hash_size - 1))
1164 hash_size--;
1165 dccp_hashinfo.ehash_mask = hash_size - 1;
1166 dccp_hashinfo.ehash = (struct inet_ehash_bucket *)
1167 __get_free_pages(GFP_ATOMIC|__GFP_NOWARN, ehash_order);
1168 } while (!dccp_hashinfo.ehash && --ehash_order > 0);
1169
1170 if (!dccp_hashinfo.ehash) {
1171 DCCP_CRIT("Failed to allocate DCCP established hash table");
1172 goto out_free_bind_bucket_cachep;
1173 }
1174
1175 for (i = 0; i <= dccp_hashinfo.ehash_mask; i++)
1176 INIT_HLIST_NULLS_HEAD(&dccp_hashinfo.ehash[i].chain, i);
1177
1178 if (inet_ehash_locks_alloc(&dccp_hashinfo))
1179 goto out_free_dccp_ehash;
1180
1181 bhash_order = ehash_order;
1182
1183 do {
1184 dccp_hashinfo.bhash_size = (1UL << bhash_order) * PAGE_SIZE /
1185 sizeof(struct inet_bind_hashbucket);
1186 if ((dccp_hashinfo.bhash_size > (64 * 1024)) &&
1187 bhash_order > 0)
1188 continue;
1189 dccp_hashinfo.bhash = (struct inet_bind_hashbucket *)
1190 __get_free_pages(GFP_ATOMIC|__GFP_NOWARN, bhash_order);
1191 } while (!dccp_hashinfo.bhash && --bhash_order >= 0);
1192
1193 if (!dccp_hashinfo.bhash) {
1194 DCCP_CRIT("Failed to allocate DCCP bind hash table");
1195 goto out_free_dccp_locks;
1196 }
1197
1198 for (i = 0; i < dccp_hashinfo.bhash_size; i++) {
1199 spin_lock_init(&dccp_hashinfo.bhash[i].lock);
1200 INIT_HLIST_HEAD(&dccp_hashinfo.bhash[i].chain);
1201 }
1202
1203 rc = dccp_mib_init();
1204 if (rc)
1205 goto out_free_dccp_bhash;
1206
1207 rc = dccp_ackvec_init();
1208 if (rc)
1209 goto out_free_dccp_mib;
1210
1211 rc = dccp_sysctl_init();
1212 if (rc)
1213 goto out_ackvec_exit;
1214
1215 rc = ccid_initialize_builtins();
1216 if (rc)
1217 goto out_sysctl_exit;
1218
1219 dccp_timestamping_init();
1220
1221 return 0;
1222
1223 out_sysctl_exit:
1224 dccp_sysctl_exit();
1225 out_ackvec_exit:
1226 dccp_ackvec_exit();
1227 out_free_dccp_mib:
1228 dccp_mib_exit();
1229 out_free_dccp_bhash:
1230 free_pages((unsigned long)dccp_hashinfo.bhash, bhash_order);
1231 out_free_dccp_locks:
1232 inet_ehash_locks_free(&dccp_hashinfo);
1233 out_free_dccp_ehash:
1234 free_pages((unsigned long)dccp_hashinfo.ehash, ehash_order);
1235 out_free_bind_bucket_cachep:
1236 kmem_cache_destroy(dccp_hashinfo.bind_bucket_cachep);
1237 out_free_percpu:
1238 percpu_counter_destroy(&dccp_orphan_count);
1239 out_fail:
1240 dccp_hashinfo.bhash = NULL;
1241 dccp_hashinfo.ehash = NULL;
1242 dccp_hashinfo.bind_bucket_cachep = NULL;
1243 return rc;
1244 }
1245
1246 static void __exit dccp_fini(void)
1247 {
1248 ccid_cleanup_builtins();
1249 dccp_mib_exit();
1250 free_pages((unsigned long)dccp_hashinfo.bhash,
1251 get_order(dccp_hashinfo.bhash_size *
1252 sizeof(struct inet_bind_hashbucket)));
1253 free_pages((unsigned long)dccp_hashinfo.ehash,
1254 get_order((dccp_hashinfo.ehash_mask + 1) *
1255 sizeof(struct inet_ehash_bucket)));
1256 inet_ehash_locks_free(&dccp_hashinfo);
1257 kmem_cache_destroy(dccp_hashinfo.bind_bucket_cachep);
1258 dccp_ackvec_exit();
1259 dccp_sysctl_exit();
1260 percpu_counter_destroy(&dccp_orphan_count);
1261 }
1262
1263 module_init(dccp_init);
1264 module_exit(dccp_fini);
1265
1266 MODULE_LICENSE("GPL");
1267 MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@conectiva.com.br>");
1268 MODULE_DESCRIPTION("DCCP - Datagram Congestion Controlled Protocol");
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