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
dccp_state_name(const int state)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
dccp_set_state(struct sock * sk,const int state)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
dccp_finish_passive_close(struct sock * sk)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
dccp_done(struct sock * sk)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
dccp_packet_name(const int type)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
dccp_sk_destruct(struct sock * sk)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
dccp_init_sock(struct sock * sk,const __u8 ctl_sock_initialized)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
dccp_destroy_sock(struct sock * sk)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
dccp_listen_start(struct sock * sk,int backlog)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
dccp_need_reset(int state)252 static inline int dccp_need_reset(int state)
253 {
254 return state != DCCP_CLOSED && state != DCCP_LISTEN &&
255 state != DCCP_REQUESTING;
256 }
257
dccp_disconnect(struct sock * sk,int flags)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 dp->dccps_hc_rx_ccid = NULL;
284
285 __skb_queue_purge(&sk->sk_receive_queue);
286 __skb_queue_purge(&sk->sk_write_queue);
287 if (sk->sk_send_head != NULL) {
288 __kfree_skb(sk->sk_send_head);
289 sk->sk_send_head = NULL;
290 }
291
292 inet->inet_dport = 0;
293
294 if (!(sk->sk_userlocks & SOCK_BINDADDR_LOCK))
295 inet_reset_saddr(sk);
296
297 sk->sk_shutdown = 0;
298 sock_reset_flag(sk, SOCK_DONE);
299
300 icsk->icsk_backoff = 0;
301 inet_csk_delack_init(sk);
302 __sk_dst_reset(sk);
303
304 WARN_ON(inet->inet_num && !icsk->icsk_bind_hash);
305
306 sk->sk_error_report(sk);
307 return err;
308 }
309
310 EXPORT_SYMBOL_GPL(dccp_disconnect);
311
312 /*
313 * Wait for a DCCP event.
314 *
315 * Note that we don't need to lock the socket, as the upper poll layers
316 * take care of normal races (between the test and the event) and we don't
317 * go look at any of the socket buffers directly.
318 */
dccp_poll(struct file * file,struct socket * sock,poll_table * wait)319 unsigned int dccp_poll(struct file *file, struct socket *sock,
320 poll_table *wait)
321 {
322 unsigned int mask;
323 struct sock *sk = sock->sk;
324
325 sock_poll_wait(file, sk_sleep(sk), wait);
326 if (sk->sk_state == DCCP_LISTEN)
327 return inet_csk_listen_poll(sk);
328
329 /* Socket is not locked. We are protected from async events
330 by poll logic and correct handling of state changes
331 made by another threads is impossible in any case.
332 */
333
334 mask = 0;
335 if (sk->sk_err)
336 mask = POLLERR;
337
338 if (sk->sk_shutdown == SHUTDOWN_MASK || sk->sk_state == DCCP_CLOSED)
339 mask |= POLLHUP;
340 if (sk->sk_shutdown & RCV_SHUTDOWN)
341 mask |= POLLIN | POLLRDNORM | POLLRDHUP;
342
343 /* Connected? */
344 if ((1 << sk->sk_state) & ~(DCCPF_REQUESTING | DCCPF_RESPOND)) {
345 if (atomic_read(&sk->sk_rmem_alloc) > 0)
346 mask |= POLLIN | POLLRDNORM;
347
348 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
349 if (sk_stream_is_writeable(sk)) {
350 mask |= POLLOUT | POLLWRNORM;
351 } else { /* send SIGIO later */
352 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
353 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
354
355 /* Race breaker. If space is freed after
356 * wspace test but before the flags are set,
357 * IO signal will be lost.
358 */
359 if (sk_stream_is_writeable(sk))
360 mask |= POLLOUT | POLLWRNORM;
361 }
362 }
363 }
364 return mask;
365 }
366
367 EXPORT_SYMBOL_GPL(dccp_poll);
368
dccp_ioctl(struct sock * sk,int cmd,unsigned long arg)369 int dccp_ioctl(struct sock *sk, int cmd, unsigned long arg)
370 {
371 int rc = -ENOTCONN;
372
373 lock_sock(sk);
374
375 if (sk->sk_state == DCCP_LISTEN)
376 goto out;
377
378 switch (cmd) {
379 case SIOCINQ: {
380 struct sk_buff *skb;
381 unsigned long amount = 0;
382
383 skb = skb_peek(&sk->sk_receive_queue);
384 if (skb != NULL) {
385 /*
386 * We will only return the amount of this packet since
387 * that is all that will be read.
388 */
389 amount = skb->len;
390 }
391 rc = put_user(amount, (int __user *)arg);
392 }
393 break;
394 default:
395 rc = -ENOIOCTLCMD;
396 break;
397 }
398 out:
399 release_sock(sk);
400 return rc;
401 }
402
403 EXPORT_SYMBOL_GPL(dccp_ioctl);
404
dccp_setsockopt_service(struct sock * sk,const __be32 service,char __user * optval,unsigned int optlen)405 static int dccp_setsockopt_service(struct sock *sk, const __be32 service,
406 char __user *optval, unsigned int optlen)
407 {
408 struct dccp_sock *dp = dccp_sk(sk);
409 struct dccp_service_list *sl = NULL;
410
411 if (service == DCCP_SERVICE_INVALID_VALUE ||
412 optlen > DCCP_SERVICE_LIST_MAX_LEN * sizeof(u32))
413 return -EINVAL;
414
415 if (optlen > sizeof(service)) {
416 sl = kmalloc(optlen, GFP_KERNEL);
417 if (sl == NULL)
418 return -ENOMEM;
419
420 sl->dccpsl_nr = optlen / sizeof(u32) - 1;
421 if (copy_from_user(sl->dccpsl_list,
422 optval + sizeof(service),
423 optlen - sizeof(service)) ||
424 dccp_list_has_service(sl, DCCP_SERVICE_INVALID_VALUE)) {
425 kfree(sl);
426 return -EFAULT;
427 }
428 }
429
430 lock_sock(sk);
431 dp->dccps_service = service;
432
433 kfree(dp->dccps_service_list);
434
435 dp->dccps_service_list = sl;
436 release_sock(sk);
437 return 0;
438 }
439
dccp_setsockopt_cscov(struct sock * sk,int cscov,bool rx)440 static int dccp_setsockopt_cscov(struct sock *sk, int cscov, bool rx)
441 {
442 u8 *list, len;
443 int i, rc;
444
445 if (cscov < 0 || cscov > 15)
446 return -EINVAL;
447 /*
448 * Populate a list of permissible values, in the range cscov...15. This
449 * is necessary since feature negotiation of single values only works if
450 * both sides incidentally choose the same value. Since the list starts
451 * lowest-value first, negotiation will pick the smallest shared value.
452 */
453 if (cscov == 0)
454 return 0;
455 len = 16 - cscov;
456
457 list = kmalloc(len, GFP_KERNEL);
458 if (list == NULL)
459 return -ENOBUFS;
460
461 for (i = 0; i < len; i++)
462 list[i] = cscov++;
463
464 rc = dccp_feat_register_sp(sk, DCCPF_MIN_CSUM_COVER, rx, list, len);
465
466 if (rc == 0) {
467 if (rx)
468 dccp_sk(sk)->dccps_pcrlen = cscov;
469 else
470 dccp_sk(sk)->dccps_pcslen = cscov;
471 }
472 kfree(list);
473 return rc;
474 }
475
dccp_setsockopt_ccid(struct sock * sk,int type,char __user * optval,unsigned int optlen)476 static int dccp_setsockopt_ccid(struct sock *sk, int type,
477 char __user *optval, unsigned int optlen)
478 {
479 u8 *val;
480 int rc = 0;
481
482 if (optlen < 1 || optlen > DCCP_FEAT_MAX_SP_VALS)
483 return -EINVAL;
484
485 val = memdup_user(optval, optlen);
486 if (IS_ERR(val))
487 return PTR_ERR(val);
488
489 lock_sock(sk);
490 if (type == DCCP_SOCKOPT_TX_CCID || type == DCCP_SOCKOPT_CCID)
491 rc = dccp_feat_register_sp(sk, DCCPF_CCID, 1, val, optlen);
492
493 if (!rc && (type == DCCP_SOCKOPT_RX_CCID || type == DCCP_SOCKOPT_CCID))
494 rc = dccp_feat_register_sp(sk, DCCPF_CCID, 0, val, optlen);
495 release_sock(sk);
496
497 kfree(val);
498 return rc;
499 }
500
do_dccp_setsockopt(struct sock * sk,int level,int optname,char __user * optval,unsigned int optlen)501 static int do_dccp_setsockopt(struct sock *sk, int level, int optname,
502 char __user *optval, unsigned int optlen)
503 {
504 struct dccp_sock *dp = dccp_sk(sk);
505 int val, err = 0;
506
507 switch (optname) {
508 case DCCP_SOCKOPT_PACKET_SIZE:
509 DCCP_WARN("sockopt(PACKET_SIZE) is deprecated: fix your app\n");
510 return 0;
511 case DCCP_SOCKOPT_CHANGE_L:
512 case DCCP_SOCKOPT_CHANGE_R:
513 DCCP_WARN("sockopt(CHANGE_L/R) is deprecated: fix your app\n");
514 return 0;
515 case DCCP_SOCKOPT_CCID:
516 case DCCP_SOCKOPT_RX_CCID:
517 case DCCP_SOCKOPT_TX_CCID:
518 return dccp_setsockopt_ccid(sk, optname, optval, optlen);
519 }
520
521 if (optlen < (int)sizeof(int))
522 return -EINVAL;
523
524 if (get_user(val, (int __user *)optval))
525 return -EFAULT;
526
527 if (optname == DCCP_SOCKOPT_SERVICE)
528 return dccp_setsockopt_service(sk, val, optval, optlen);
529
530 lock_sock(sk);
531 switch (optname) {
532 case DCCP_SOCKOPT_SERVER_TIMEWAIT:
533 if (dp->dccps_role != DCCP_ROLE_SERVER)
534 err = -EOPNOTSUPP;
535 else
536 dp->dccps_server_timewait = (val != 0);
537 break;
538 case DCCP_SOCKOPT_SEND_CSCOV:
539 err = dccp_setsockopt_cscov(sk, val, false);
540 break;
541 case DCCP_SOCKOPT_RECV_CSCOV:
542 err = dccp_setsockopt_cscov(sk, val, true);
543 break;
544 case DCCP_SOCKOPT_QPOLICY_ID:
545 if (sk->sk_state != DCCP_CLOSED)
546 err = -EISCONN;
547 else if (val < 0 || val >= DCCPQ_POLICY_MAX)
548 err = -EINVAL;
549 else
550 dp->dccps_qpolicy = val;
551 break;
552 case DCCP_SOCKOPT_QPOLICY_TXQLEN:
553 if (val < 0)
554 err = -EINVAL;
555 else
556 dp->dccps_tx_qlen = val;
557 break;
558 default:
559 err = -ENOPROTOOPT;
560 break;
561 }
562 release_sock(sk);
563
564 return err;
565 }
566
dccp_setsockopt(struct sock * sk,int level,int optname,char __user * optval,unsigned int optlen)567 int dccp_setsockopt(struct sock *sk, int level, int optname,
568 char __user *optval, unsigned int optlen)
569 {
570 if (level != SOL_DCCP)
571 return inet_csk(sk)->icsk_af_ops->setsockopt(sk, level,
572 optname, optval,
573 optlen);
574 return do_dccp_setsockopt(sk, level, optname, optval, optlen);
575 }
576
577 EXPORT_SYMBOL_GPL(dccp_setsockopt);
578
579 #ifdef CONFIG_COMPAT
compat_dccp_setsockopt(struct sock * sk,int level,int optname,char __user * optval,unsigned int optlen)580 int compat_dccp_setsockopt(struct sock *sk, int level, int optname,
581 char __user *optval, unsigned int optlen)
582 {
583 if (level != SOL_DCCP)
584 return inet_csk_compat_setsockopt(sk, level, optname,
585 optval, optlen);
586 return do_dccp_setsockopt(sk, level, optname, optval, optlen);
587 }
588
589 EXPORT_SYMBOL_GPL(compat_dccp_setsockopt);
590 #endif
591
dccp_getsockopt_service(struct sock * sk,int len,__be32 __user * optval,int __user * optlen)592 static int dccp_getsockopt_service(struct sock *sk, int len,
593 __be32 __user *optval,
594 int __user *optlen)
595 {
596 const struct dccp_sock *dp = dccp_sk(sk);
597 const struct dccp_service_list *sl;
598 int err = -ENOENT, slen = 0, total_len = sizeof(u32);
599
600 lock_sock(sk);
601 if ((sl = dp->dccps_service_list) != NULL) {
602 slen = sl->dccpsl_nr * sizeof(u32);
603 total_len += slen;
604 }
605
606 err = -EINVAL;
607 if (total_len > len)
608 goto out;
609
610 err = 0;
611 if (put_user(total_len, optlen) ||
612 put_user(dp->dccps_service, optval) ||
613 (sl != NULL && copy_to_user(optval + 1, sl->dccpsl_list, slen)))
614 err = -EFAULT;
615 out:
616 release_sock(sk);
617 return err;
618 }
619
do_dccp_getsockopt(struct sock * sk,int level,int optname,char __user * optval,int __user * optlen)620 static int do_dccp_getsockopt(struct sock *sk, int level, int optname,
621 char __user *optval, int __user *optlen)
622 {
623 struct dccp_sock *dp;
624 int val, len;
625
626 if (get_user(len, optlen))
627 return -EFAULT;
628
629 if (len < (int)sizeof(int))
630 return -EINVAL;
631
632 dp = dccp_sk(sk);
633
634 switch (optname) {
635 case DCCP_SOCKOPT_PACKET_SIZE:
636 DCCP_WARN("sockopt(PACKET_SIZE) is deprecated: fix your app\n");
637 return 0;
638 case DCCP_SOCKOPT_SERVICE:
639 return dccp_getsockopt_service(sk, len,
640 (__be32 __user *)optval, optlen);
641 case DCCP_SOCKOPT_GET_CUR_MPS:
642 val = dp->dccps_mss_cache;
643 break;
644 case DCCP_SOCKOPT_AVAILABLE_CCIDS:
645 return ccid_getsockopt_builtin_ccids(sk, len, optval, optlen);
646 case DCCP_SOCKOPT_TX_CCID:
647 val = ccid_get_current_tx_ccid(dp);
648 if (val < 0)
649 return -ENOPROTOOPT;
650 break;
651 case DCCP_SOCKOPT_RX_CCID:
652 val = ccid_get_current_rx_ccid(dp);
653 if (val < 0)
654 return -ENOPROTOOPT;
655 break;
656 case DCCP_SOCKOPT_SERVER_TIMEWAIT:
657 val = dp->dccps_server_timewait;
658 break;
659 case DCCP_SOCKOPT_SEND_CSCOV:
660 val = dp->dccps_pcslen;
661 break;
662 case DCCP_SOCKOPT_RECV_CSCOV:
663 val = dp->dccps_pcrlen;
664 break;
665 case DCCP_SOCKOPT_QPOLICY_ID:
666 val = dp->dccps_qpolicy;
667 break;
668 case DCCP_SOCKOPT_QPOLICY_TXQLEN:
669 val = dp->dccps_tx_qlen;
670 break;
671 case 128 ... 191:
672 return ccid_hc_rx_getsockopt(dp->dccps_hc_rx_ccid, sk, optname,
673 len, (u32 __user *)optval, optlen);
674 case 192 ... 255:
675 return ccid_hc_tx_getsockopt(dp->dccps_hc_tx_ccid, sk, optname,
676 len, (u32 __user *)optval, optlen);
677 default:
678 return -ENOPROTOOPT;
679 }
680
681 len = sizeof(val);
682 if (put_user(len, optlen) || copy_to_user(optval, &val, len))
683 return -EFAULT;
684
685 return 0;
686 }
687
dccp_getsockopt(struct sock * sk,int level,int optname,char __user * optval,int __user * optlen)688 int dccp_getsockopt(struct sock *sk, int level, int optname,
689 char __user *optval, int __user *optlen)
690 {
691 if (level != SOL_DCCP)
692 return inet_csk(sk)->icsk_af_ops->getsockopt(sk, level,
693 optname, optval,
694 optlen);
695 return do_dccp_getsockopt(sk, level, optname, optval, optlen);
696 }
697
698 EXPORT_SYMBOL_GPL(dccp_getsockopt);
699
700 #ifdef CONFIG_COMPAT
compat_dccp_getsockopt(struct sock * sk,int level,int optname,char __user * optval,int __user * optlen)701 int compat_dccp_getsockopt(struct sock *sk, int level, int optname,
702 char __user *optval, int __user *optlen)
703 {
704 if (level != SOL_DCCP)
705 return inet_csk_compat_getsockopt(sk, level, optname,
706 optval, optlen);
707 return do_dccp_getsockopt(sk, level, optname, optval, optlen);
708 }
709
710 EXPORT_SYMBOL_GPL(compat_dccp_getsockopt);
711 #endif
712
dccp_msghdr_parse(struct msghdr * msg,struct sk_buff * skb)713 static int dccp_msghdr_parse(struct msghdr *msg, struct sk_buff *skb)
714 {
715 struct cmsghdr *cmsg;
716
717 /*
718 * Assign an (opaque) qpolicy priority value to skb->priority.
719 *
720 * We are overloading this skb field for use with the qpolicy subystem.
721 * The skb->priority is normally used for the SO_PRIORITY option, which
722 * is initialised from sk_priority. Since the assignment of sk_priority
723 * to skb->priority happens later (on layer 3), we overload this field
724 * for use with queueing priorities as long as the skb is on layer 4.
725 * The default priority value (if nothing is set) is 0.
726 */
727 skb->priority = 0;
728
729 for_each_cmsghdr(cmsg, msg) {
730 if (!CMSG_OK(msg, cmsg))
731 return -EINVAL;
732
733 if (cmsg->cmsg_level != SOL_DCCP)
734 continue;
735
736 if (cmsg->cmsg_type <= DCCP_SCM_QPOLICY_MAX &&
737 !dccp_qpolicy_param_ok(skb->sk, cmsg->cmsg_type))
738 return -EINVAL;
739
740 switch (cmsg->cmsg_type) {
741 case DCCP_SCM_PRIORITY:
742 if (cmsg->cmsg_len != CMSG_LEN(sizeof(__u32)))
743 return -EINVAL;
744 skb->priority = *(__u32 *)CMSG_DATA(cmsg);
745 break;
746 default:
747 return -EINVAL;
748 }
749 }
750 return 0;
751 }
752
dccp_sendmsg(struct sock * sk,struct msghdr * msg,size_t len)753 int dccp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
754 {
755 const struct dccp_sock *dp = dccp_sk(sk);
756 const int flags = msg->msg_flags;
757 const int noblock = flags & MSG_DONTWAIT;
758 struct sk_buff *skb;
759 int rc, size;
760 long timeo;
761
762 if (len > dp->dccps_mss_cache)
763 return -EMSGSIZE;
764
765 lock_sock(sk);
766
767 if (dccp_qpolicy_full(sk)) {
768 rc = -EAGAIN;
769 goto out_release;
770 }
771
772 timeo = sock_sndtimeo(sk, noblock);
773
774 /*
775 * We have to use sk_stream_wait_connect here to set sk_write_pending,
776 * so that the trick in dccp_rcv_request_sent_state_process.
777 */
778 /* Wait for a connection to finish. */
779 if ((1 << sk->sk_state) & ~(DCCPF_OPEN | DCCPF_PARTOPEN))
780 if ((rc = sk_stream_wait_connect(sk, &timeo)) != 0)
781 goto out_release;
782
783 size = sk->sk_prot->max_header + len;
784 release_sock(sk);
785 skb = sock_alloc_send_skb(sk, size, noblock, &rc);
786 lock_sock(sk);
787 if (skb == NULL)
788 goto out_release;
789
790 if (sk->sk_state == DCCP_CLOSED) {
791 rc = -ENOTCONN;
792 goto out_discard;
793 }
794
795 skb_reserve(skb, sk->sk_prot->max_header);
796 rc = memcpy_from_msg(skb_put(skb, len), msg, len);
797 if (rc != 0)
798 goto out_discard;
799
800 rc = dccp_msghdr_parse(msg, skb);
801 if (rc != 0)
802 goto out_discard;
803
804 dccp_qpolicy_push(sk, skb);
805 /*
806 * The xmit_timer is set if the TX CCID is rate-based and will expire
807 * when congestion control permits to release further packets into the
808 * network. Window-based CCIDs do not use this timer.
809 */
810 if (!timer_pending(&dp->dccps_xmit_timer))
811 dccp_write_xmit(sk);
812 out_release:
813 release_sock(sk);
814 return rc ? : len;
815 out_discard:
816 kfree_skb(skb);
817 goto out_release;
818 }
819
820 EXPORT_SYMBOL_GPL(dccp_sendmsg);
821
dccp_recvmsg(struct sock * sk,struct msghdr * msg,size_t len,int nonblock,int flags,int * addr_len)822 int dccp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int nonblock,
823 int flags, int *addr_len)
824 {
825 const struct dccp_hdr *dh;
826 long timeo;
827
828 lock_sock(sk);
829
830 if (sk->sk_state == DCCP_LISTEN) {
831 len = -ENOTCONN;
832 goto out;
833 }
834
835 timeo = sock_rcvtimeo(sk, nonblock);
836
837 do {
838 struct sk_buff *skb = skb_peek(&sk->sk_receive_queue);
839
840 if (skb == NULL)
841 goto verify_sock_status;
842
843 dh = dccp_hdr(skb);
844
845 switch (dh->dccph_type) {
846 case DCCP_PKT_DATA:
847 case DCCP_PKT_DATAACK:
848 goto found_ok_skb;
849
850 case DCCP_PKT_CLOSE:
851 case DCCP_PKT_CLOSEREQ:
852 if (!(flags & MSG_PEEK))
853 dccp_finish_passive_close(sk);
854 /* fall through */
855 case DCCP_PKT_RESET:
856 dccp_pr_debug("found fin (%s) ok!\n",
857 dccp_packet_name(dh->dccph_type));
858 len = 0;
859 goto found_fin_ok;
860 default:
861 dccp_pr_debug("packet_type=%s\n",
862 dccp_packet_name(dh->dccph_type));
863 sk_eat_skb(sk, skb);
864 }
865 verify_sock_status:
866 if (sock_flag(sk, SOCK_DONE)) {
867 len = 0;
868 break;
869 }
870
871 if (sk->sk_err) {
872 len = sock_error(sk);
873 break;
874 }
875
876 if (sk->sk_shutdown & RCV_SHUTDOWN) {
877 len = 0;
878 break;
879 }
880
881 if (sk->sk_state == DCCP_CLOSED) {
882 if (!sock_flag(sk, SOCK_DONE)) {
883 /* This occurs when user tries to read
884 * from never connected socket.
885 */
886 len = -ENOTCONN;
887 break;
888 }
889 len = 0;
890 break;
891 }
892
893 if (!timeo) {
894 len = -EAGAIN;
895 break;
896 }
897
898 if (signal_pending(current)) {
899 len = sock_intr_errno(timeo);
900 break;
901 }
902
903 sk_wait_data(sk, &timeo, NULL);
904 continue;
905 found_ok_skb:
906 if (len > skb->len)
907 len = skb->len;
908 else if (len < skb->len)
909 msg->msg_flags |= MSG_TRUNC;
910
911 if (skb_copy_datagram_msg(skb, 0, msg, len)) {
912 /* Exception. Bailout! */
913 len = -EFAULT;
914 break;
915 }
916 if (flags & MSG_TRUNC)
917 len = skb->len;
918 found_fin_ok:
919 if (!(flags & MSG_PEEK))
920 sk_eat_skb(sk, skb);
921 break;
922 } while (1);
923 out:
924 release_sock(sk);
925 return len;
926 }
927
928 EXPORT_SYMBOL_GPL(dccp_recvmsg);
929
inet_dccp_listen(struct socket * sock,int backlog)930 int inet_dccp_listen(struct socket *sock, int backlog)
931 {
932 struct sock *sk = sock->sk;
933 unsigned char old_state;
934 int err;
935
936 lock_sock(sk);
937
938 err = -EINVAL;
939 if (sock->state != SS_UNCONNECTED || sock->type != SOCK_DCCP)
940 goto out;
941
942 old_state = sk->sk_state;
943 if (!((1 << old_state) & (DCCPF_CLOSED | DCCPF_LISTEN)))
944 goto out;
945
946 /* Really, if the socket is already in listen state
947 * we can only allow the backlog to be adjusted.
948 */
949 if (old_state != DCCP_LISTEN) {
950 /*
951 * FIXME: here it probably should be sk->sk_prot->listen_start
952 * see tcp_listen_start
953 */
954 err = dccp_listen_start(sk, backlog);
955 if (err)
956 goto out;
957 }
958 sk->sk_max_ack_backlog = backlog;
959 err = 0;
960
961 out:
962 release_sock(sk);
963 return err;
964 }
965
966 EXPORT_SYMBOL_GPL(inet_dccp_listen);
967
dccp_terminate_connection(struct sock * sk)968 static void dccp_terminate_connection(struct sock *sk)
969 {
970 u8 next_state = DCCP_CLOSED;
971
972 switch (sk->sk_state) {
973 case DCCP_PASSIVE_CLOSE:
974 case DCCP_PASSIVE_CLOSEREQ:
975 dccp_finish_passive_close(sk);
976 break;
977 case DCCP_PARTOPEN:
978 dccp_pr_debug("Stop PARTOPEN timer (%p)\n", sk);
979 inet_csk_clear_xmit_timer(sk, ICSK_TIME_DACK);
980 /* fall through */
981 case DCCP_OPEN:
982 dccp_send_close(sk, 1);
983
984 if (dccp_sk(sk)->dccps_role == DCCP_ROLE_SERVER &&
985 !dccp_sk(sk)->dccps_server_timewait)
986 next_state = DCCP_ACTIVE_CLOSEREQ;
987 else
988 next_state = DCCP_CLOSING;
989 /* fall through */
990 default:
991 dccp_set_state(sk, next_state);
992 }
993 }
994
dccp_close(struct sock * sk,long timeout)995 void dccp_close(struct sock *sk, long timeout)
996 {
997 struct dccp_sock *dp = dccp_sk(sk);
998 struct sk_buff *skb;
999 u32 data_was_unread = 0;
1000 int state;
1001
1002 lock_sock(sk);
1003
1004 sk->sk_shutdown = SHUTDOWN_MASK;
1005
1006 if (sk->sk_state == DCCP_LISTEN) {
1007 dccp_set_state(sk, DCCP_CLOSED);
1008
1009 /* Special case. */
1010 inet_csk_listen_stop(sk);
1011
1012 goto adjudge_to_death;
1013 }
1014
1015 sk_stop_timer(sk, &dp->dccps_xmit_timer);
1016
1017 /*
1018 * We need to flush the recv. buffs. We do this only on the
1019 * descriptor close, not protocol-sourced closes, because the
1020 *reader process may not have drained the data yet!
1021 */
1022 while ((skb = __skb_dequeue(&sk->sk_receive_queue)) != NULL) {
1023 data_was_unread += skb->len;
1024 __kfree_skb(skb);
1025 }
1026
1027 /* If socket has been already reset kill it. */
1028 if (sk->sk_state == DCCP_CLOSED)
1029 goto adjudge_to_death;
1030
1031 if (data_was_unread) {
1032 /* Unread data was tossed, send an appropriate Reset Code */
1033 DCCP_WARN("ABORT with %u bytes unread\n", data_was_unread);
1034 dccp_send_reset(sk, DCCP_RESET_CODE_ABORTED);
1035 dccp_set_state(sk, DCCP_CLOSED);
1036 } else if (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime) {
1037 /* Check zero linger _after_ checking for unread data. */
1038 sk->sk_prot->disconnect(sk, 0);
1039 } else if (sk->sk_state != DCCP_CLOSED) {
1040 /*
1041 * Normal connection termination. May need to wait if there are
1042 * still packets in the TX queue that are delayed by the CCID.
1043 */
1044 dccp_flush_write_queue(sk, &timeout);
1045 dccp_terminate_connection(sk);
1046 }
1047
1048 /*
1049 * Flush write queue. This may be necessary in several cases:
1050 * - we have been closed by the peer but still have application data;
1051 * - abortive termination (unread data or zero linger time),
1052 * - normal termination but queue could not be flushed within time limit
1053 */
1054 __skb_queue_purge(&sk->sk_write_queue);
1055
1056 sk_stream_wait_close(sk, timeout);
1057
1058 adjudge_to_death:
1059 state = sk->sk_state;
1060 sock_hold(sk);
1061 sock_orphan(sk);
1062
1063 /*
1064 * It is the last release_sock in its life. It will remove backlog.
1065 */
1066 release_sock(sk);
1067 /*
1068 * Now socket is owned by kernel and we acquire BH lock
1069 * to finish close. No need to check for user refs.
1070 */
1071 local_bh_disable();
1072 bh_lock_sock(sk);
1073 WARN_ON(sock_owned_by_user(sk));
1074
1075 percpu_counter_inc(sk->sk_prot->orphan_count);
1076
1077 /* Have we already been destroyed by a softirq or backlog? */
1078 if (state != DCCP_CLOSED && sk->sk_state == DCCP_CLOSED)
1079 goto out;
1080
1081 if (sk->sk_state == DCCP_CLOSED)
1082 inet_csk_destroy_sock(sk);
1083
1084 /* Otherwise, socket is reprieved until protocol close. */
1085
1086 out:
1087 bh_unlock_sock(sk);
1088 local_bh_enable();
1089 sock_put(sk);
1090 }
1091
1092 EXPORT_SYMBOL_GPL(dccp_close);
1093
dccp_shutdown(struct sock * sk,int how)1094 void dccp_shutdown(struct sock *sk, int how)
1095 {
1096 dccp_pr_debug("called shutdown(%x)\n", how);
1097 }
1098
1099 EXPORT_SYMBOL_GPL(dccp_shutdown);
1100
dccp_mib_init(void)1101 static inline int __init dccp_mib_init(void)
1102 {
1103 dccp_statistics = alloc_percpu(struct dccp_mib);
1104 if (!dccp_statistics)
1105 return -ENOMEM;
1106 return 0;
1107 }
1108
dccp_mib_exit(void)1109 static inline void dccp_mib_exit(void)
1110 {
1111 free_percpu(dccp_statistics);
1112 }
1113
1114 static int thash_entries;
1115 module_param(thash_entries, int, 0444);
1116 MODULE_PARM_DESC(thash_entries, "Number of ehash buckets");
1117
1118 #ifdef CONFIG_IP_DCCP_DEBUG
1119 bool dccp_debug;
1120 module_param(dccp_debug, bool, 0644);
1121 MODULE_PARM_DESC(dccp_debug, "Enable debug messages");
1122
1123 EXPORT_SYMBOL_GPL(dccp_debug);
1124 #endif
1125
dccp_init(void)1126 static int __init dccp_init(void)
1127 {
1128 unsigned long goal;
1129 int ehash_order, bhash_order, i;
1130 int rc;
1131
1132 BUILD_BUG_ON(sizeof(struct dccp_skb_cb) >
1133 FIELD_SIZEOF(struct sk_buff, cb));
1134 rc = percpu_counter_init(&dccp_orphan_count, 0, GFP_KERNEL);
1135 if (rc)
1136 goto out_fail;
1137 rc = -ENOBUFS;
1138 inet_hashinfo_init(&dccp_hashinfo);
1139 dccp_hashinfo.bind_bucket_cachep =
1140 kmem_cache_create("dccp_bind_bucket",
1141 sizeof(struct inet_bind_bucket), 0,
1142 SLAB_HWCACHE_ALIGN, NULL);
1143 if (!dccp_hashinfo.bind_bucket_cachep)
1144 goto out_free_percpu;
1145
1146 /*
1147 * Size and allocate the main established and bind bucket
1148 * hash tables.
1149 *
1150 * The methodology is similar to that of the buffer cache.
1151 */
1152 if (totalram_pages >= (128 * 1024))
1153 goal = totalram_pages >> (21 - PAGE_SHIFT);
1154 else
1155 goal = totalram_pages >> (23 - PAGE_SHIFT);
1156
1157 if (thash_entries)
1158 goal = (thash_entries *
1159 sizeof(struct inet_ehash_bucket)) >> PAGE_SHIFT;
1160 for (ehash_order = 0; (1UL << ehash_order) < goal; ehash_order++)
1161 ;
1162 do {
1163 unsigned long hash_size = (1UL << ehash_order) * PAGE_SIZE /
1164 sizeof(struct inet_ehash_bucket);
1165
1166 while (hash_size & (hash_size - 1))
1167 hash_size--;
1168 dccp_hashinfo.ehash_mask = hash_size - 1;
1169 dccp_hashinfo.ehash = (struct inet_ehash_bucket *)
1170 __get_free_pages(GFP_ATOMIC|__GFP_NOWARN, ehash_order);
1171 } while (!dccp_hashinfo.ehash && --ehash_order > 0);
1172
1173 if (!dccp_hashinfo.ehash) {
1174 DCCP_CRIT("Failed to allocate DCCP established hash table");
1175 goto out_free_bind_bucket_cachep;
1176 }
1177
1178 for (i = 0; i <= dccp_hashinfo.ehash_mask; i++)
1179 INIT_HLIST_NULLS_HEAD(&dccp_hashinfo.ehash[i].chain, i);
1180
1181 if (inet_ehash_locks_alloc(&dccp_hashinfo))
1182 goto out_free_dccp_ehash;
1183
1184 bhash_order = ehash_order;
1185
1186 do {
1187 dccp_hashinfo.bhash_size = (1UL << bhash_order) * PAGE_SIZE /
1188 sizeof(struct inet_bind_hashbucket);
1189 if ((dccp_hashinfo.bhash_size > (64 * 1024)) &&
1190 bhash_order > 0)
1191 continue;
1192 dccp_hashinfo.bhash = (struct inet_bind_hashbucket *)
1193 __get_free_pages(GFP_ATOMIC|__GFP_NOWARN, bhash_order);
1194 } while (!dccp_hashinfo.bhash && --bhash_order >= 0);
1195
1196 if (!dccp_hashinfo.bhash) {
1197 DCCP_CRIT("Failed to allocate DCCP bind hash table");
1198 goto out_free_dccp_locks;
1199 }
1200
1201 for (i = 0; i < dccp_hashinfo.bhash_size; i++) {
1202 spin_lock_init(&dccp_hashinfo.bhash[i].lock);
1203 INIT_HLIST_HEAD(&dccp_hashinfo.bhash[i].chain);
1204 }
1205
1206 rc = dccp_mib_init();
1207 if (rc)
1208 goto out_free_dccp_bhash;
1209
1210 rc = dccp_ackvec_init();
1211 if (rc)
1212 goto out_free_dccp_mib;
1213
1214 rc = dccp_sysctl_init();
1215 if (rc)
1216 goto out_ackvec_exit;
1217
1218 rc = ccid_initialize_builtins();
1219 if (rc)
1220 goto out_sysctl_exit;
1221
1222 dccp_timestamping_init();
1223
1224 return 0;
1225
1226 out_sysctl_exit:
1227 dccp_sysctl_exit();
1228 out_ackvec_exit:
1229 dccp_ackvec_exit();
1230 out_free_dccp_mib:
1231 dccp_mib_exit();
1232 out_free_dccp_bhash:
1233 free_pages((unsigned long)dccp_hashinfo.bhash, bhash_order);
1234 out_free_dccp_locks:
1235 inet_ehash_locks_free(&dccp_hashinfo);
1236 out_free_dccp_ehash:
1237 free_pages((unsigned long)dccp_hashinfo.ehash, ehash_order);
1238 out_free_bind_bucket_cachep:
1239 kmem_cache_destroy(dccp_hashinfo.bind_bucket_cachep);
1240 out_free_percpu:
1241 percpu_counter_destroy(&dccp_orphan_count);
1242 out_fail:
1243 dccp_hashinfo.bhash = NULL;
1244 dccp_hashinfo.ehash = NULL;
1245 dccp_hashinfo.bind_bucket_cachep = NULL;
1246 return rc;
1247 }
1248
dccp_fini(void)1249 static void __exit dccp_fini(void)
1250 {
1251 ccid_cleanup_builtins();
1252 dccp_mib_exit();
1253 free_pages((unsigned long)dccp_hashinfo.bhash,
1254 get_order(dccp_hashinfo.bhash_size *
1255 sizeof(struct inet_bind_hashbucket)));
1256 free_pages((unsigned long)dccp_hashinfo.ehash,
1257 get_order((dccp_hashinfo.ehash_mask + 1) *
1258 sizeof(struct inet_ehash_bucket)));
1259 inet_ehash_locks_free(&dccp_hashinfo);
1260 kmem_cache_destroy(dccp_hashinfo.bind_bucket_cachep);
1261 dccp_ackvec_exit();
1262 dccp_sysctl_exit();
1263 percpu_counter_destroy(&dccp_orphan_count);
1264 }
1265
1266 module_init(dccp_init);
1267 module_exit(dccp_fini);
1268
1269 MODULE_LICENSE("GPL");
1270 MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@conectiva.com.br>");
1271 MODULE_DESCRIPTION("DCCP - Datagram Congestion Controlled Protocol");
1272