1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * net/dccp/proto.c
4 *
5 * An implementation of the DCCP protocol
6 * Arnaldo Carvalho de Melo <acme@conectiva.com.br>
7 */
8
9 #include <linux/dccp.h>
10 #include <linux/module.h>
11 #include <linux/types.h>
12 #include <linux/sched.h>
13 #include <linux/kernel.h>
14 #include <linux/skbuff.h>
15 #include <linux/netdevice.h>
16 #include <linux/in.h>
17 #include <linux/if_arp.h>
18 #include <linux/init.h>
19 #include <linux/random.h>
20 #include <linux/slab.h>
21 #include <net/checksum.h>
22
23 #include <net/inet_sock.h>
24 #include <net/inet_common.h>
25 #include <net/sock.h>
26 #include <net/xfrm.h>
27
28 #include <asm/ioctls.h>
29 #include <linux/spinlock.h>
30 #include <linux/timer.h>
31 #include <linux/delay.h>
32 #include <linux/poll.h>
33
34 #include "ccid.h"
35 #include "dccp.h"
36 #include "feat.h"
37
38 #define CREATE_TRACE_POINTS
39 #include "trace.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 inet_sk_set_state(sk, 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 const int old_state = sk->sk_state;
264
265 if (old_state != DCCP_CLOSED)
266 dccp_set_state(sk, DCCP_CLOSED);
267
268 /*
269 * This corresponds to the ABORT function of RFC793, sec. 3.8
270 * TCP uses a RST segment, DCCP a Reset packet with Code 2, "Aborted".
271 */
272 if (old_state == DCCP_LISTEN) {
273 inet_csk_listen_stop(sk);
274 } else if (dccp_need_reset(old_state)) {
275 dccp_send_reset(sk, DCCP_RESET_CODE_ABORTED);
276 sk->sk_err = ECONNRESET;
277 } else if (old_state == DCCP_REQUESTING)
278 sk->sk_err = ECONNRESET;
279
280 dccp_clear_xmit_timers(sk);
281 ccid_hc_rx_delete(dp->dccps_hc_rx_ccid, sk);
282 dp->dccps_hc_rx_ccid = NULL;
283
284 __skb_queue_purge(&sk->sk_receive_queue);
285 __skb_queue_purge(&sk->sk_write_queue);
286 if (sk->sk_send_head != NULL) {
287 __kfree_skb(sk->sk_send_head);
288 sk->sk_send_head = NULL;
289 }
290
291 inet->inet_dport = 0;
292
293 if (!(sk->sk_userlocks & SOCK_BINDADDR_LOCK))
294 inet_reset_saddr(sk);
295
296 sk->sk_shutdown = 0;
297 sock_reset_flag(sk, SOCK_DONE);
298
299 icsk->icsk_backoff = 0;
300 inet_csk_delack_init(sk);
301 __sk_dst_reset(sk);
302
303 WARN_ON(inet->inet_num && !icsk->icsk_bind_hash);
304
305 sk->sk_error_report(sk);
306 return 0;
307 }
308
309 EXPORT_SYMBOL_GPL(dccp_disconnect);
310
311 /*
312 * Wait for a DCCP event.
313 *
314 * Note that we don't need to lock the socket, as the upper poll layers
315 * take care of normal races (between the test and the event) and we don't
316 * go look at any of the socket buffers directly.
317 */
dccp_poll(struct file * file,struct socket * sock,poll_table * wait)318 __poll_t dccp_poll(struct file *file, struct socket *sock,
319 poll_table *wait)
320 {
321 __poll_t mask;
322 struct sock *sk = sock->sk;
323
324 sock_poll_wait(file, sock, wait);
325 if (sk->sk_state == DCCP_LISTEN)
326 return inet_csk_listen_poll(sk);
327
328 /* Socket is not locked. We are protected from async events
329 by poll logic and correct handling of state changes
330 made by another threads is impossible in any case.
331 */
332
333 mask = 0;
334 if (sk->sk_err)
335 mask = EPOLLERR;
336
337 if (sk->sk_shutdown == SHUTDOWN_MASK || sk->sk_state == DCCP_CLOSED)
338 mask |= EPOLLHUP;
339 if (sk->sk_shutdown & RCV_SHUTDOWN)
340 mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP;
341
342 /* Connected? */
343 if ((1 << sk->sk_state) & ~(DCCPF_REQUESTING | DCCPF_RESPOND)) {
344 if (atomic_read(&sk->sk_rmem_alloc) > 0)
345 mask |= EPOLLIN | EPOLLRDNORM;
346
347 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
348 if (sk_stream_is_writeable(sk)) {
349 mask |= EPOLLOUT | EPOLLWRNORM;
350 } else { /* send SIGIO later */
351 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
352 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
353
354 /* Race breaker. If space is freed after
355 * wspace test but before the flags are set,
356 * IO signal will be lost.
357 */
358 if (sk_stream_is_writeable(sk))
359 mask |= EPOLLOUT | EPOLLWRNORM;
360 }
361 }
362 }
363 return mask;
364 }
365
366 EXPORT_SYMBOL_GPL(dccp_poll);
367
dccp_ioctl(struct sock * sk,int cmd,unsigned long arg)368 int dccp_ioctl(struct sock *sk, int cmd, unsigned long arg)
369 {
370 int rc = -ENOTCONN;
371
372 lock_sock(sk);
373
374 if (sk->sk_state == DCCP_LISTEN)
375 goto out;
376
377 switch (cmd) {
378 case SIOCINQ: {
379 struct sk_buff *skb;
380 unsigned long amount = 0;
381
382 skb = skb_peek(&sk->sk_receive_queue);
383 if (skb != NULL) {
384 /*
385 * We will only return the amount of this packet since
386 * that is all that will be read.
387 */
388 amount = skb->len;
389 }
390 rc = put_user(amount, (int __user *)arg);
391 }
392 break;
393 default:
394 rc = -ENOIOCTLCMD;
395 break;
396 }
397 out:
398 release_sock(sk);
399 return rc;
400 }
401
402 EXPORT_SYMBOL_GPL(dccp_ioctl);
403
dccp_setsockopt_service(struct sock * sk,const __be32 service,char __user * optval,unsigned int optlen)404 static int dccp_setsockopt_service(struct sock *sk, const __be32 service,
405 char __user *optval, unsigned int optlen)
406 {
407 struct dccp_sock *dp = dccp_sk(sk);
408 struct dccp_service_list *sl = NULL;
409
410 if (service == DCCP_SERVICE_INVALID_VALUE ||
411 optlen > DCCP_SERVICE_LIST_MAX_LEN * sizeof(u32))
412 return -EINVAL;
413
414 if (optlen > sizeof(service)) {
415 sl = kmalloc(optlen, GFP_KERNEL);
416 if (sl == NULL)
417 return -ENOMEM;
418
419 sl->dccpsl_nr = optlen / sizeof(u32) - 1;
420 if (copy_from_user(sl->dccpsl_list,
421 optval + sizeof(service),
422 optlen - sizeof(service)) ||
423 dccp_list_has_service(sl, DCCP_SERVICE_INVALID_VALUE)) {
424 kfree(sl);
425 return -EFAULT;
426 }
427 }
428
429 lock_sock(sk);
430 dp->dccps_service = service;
431
432 kfree(dp->dccps_service_list);
433
434 dp->dccps_service_list = sl;
435 release_sock(sk);
436 return 0;
437 }
438
dccp_setsockopt_cscov(struct sock * sk,int cscov,bool rx)439 static int dccp_setsockopt_cscov(struct sock *sk, int cscov, bool rx)
440 {
441 u8 *list, len;
442 int i, rc;
443
444 if (cscov < 0 || cscov > 15)
445 return -EINVAL;
446 /*
447 * Populate a list of permissible values, in the range cscov...15. This
448 * is necessary since feature negotiation of single values only works if
449 * both sides incidentally choose the same value. Since the list starts
450 * lowest-value first, negotiation will pick the smallest shared value.
451 */
452 if (cscov == 0)
453 return 0;
454 len = 16 - cscov;
455
456 list = kmalloc(len, GFP_KERNEL);
457 if (list == NULL)
458 return -ENOBUFS;
459
460 for (i = 0; i < len; i++)
461 list[i] = cscov++;
462
463 rc = dccp_feat_register_sp(sk, DCCPF_MIN_CSUM_COVER, rx, list, len);
464
465 if (rc == 0) {
466 if (rx)
467 dccp_sk(sk)->dccps_pcrlen = cscov;
468 else
469 dccp_sk(sk)->dccps_pcslen = cscov;
470 }
471 kfree(list);
472 return rc;
473 }
474
dccp_setsockopt_ccid(struct sock * sk,int type,char __user * optval,unsigned int optlen)475 static int dccp_setsockopt_ccid(struct sock *sk, int type,
476 char __user *optval, unsigned int optlen)
477 {
478 u8 *val;
479 int rc = 0;
480
481 if (optlen < 1 || optlen > DCCP_FEAT_MAX_SP_VALS)
482 return -EINVAL;
483
484 val = memdup_user(optval, optlen);
485 if (IS_ERR(val))
486 return PTR_ERR(val);
487
488 lock_sock(sk);
489 if (type == DCCP_SOCKOPT_TX_CCID || type == DCCP_SOCKOPT_CCID)
490 rc = dccp_feat_register_sp(sk, DCCPF_CCID, 1, val, optlen);
491
492 if (!rc && (type == DCCP_SOCKOPT_RX_CCID || type == DCCP_SOCKOPT_CCID))
493 rc = dccp_feat_register_sp(sk, DCCPF_CCID, 0, val, optlen);
494 release_sock(sk);
495
496 kfree(val);
497 return rc;
498 }
499
do_dccp_setsockopt(struct sock * sk,int level,int optname,char __user * optval,unsigned int optlen)500 static int do_dccp_setsockopt(struct sock *sk, int level, int optname,
501 char __user *optval, unsigned int optlen)
502 {
503 struct dccp_sock *dp = dccp_sk(sk);
504 int val, err = 0;
505
506 switch (optname) {
507 case DCCP_SOCKOPT_PACKET_SIZE:
508 DCCP_WARN("sockopt(PACKET_SIZE) is deprecated: fix your app\n");
509 return 0;
510 case DCCP_SOCKOPT_CHANGE_L:
511 case DCCP_SOCKOPT_CHANGE_R:
512 DCCP_WARN("sockopt(CHANGE_L/R) is deprecated: fix your app\n");
513 return 0;
514 case DCCP_SOCKOPT_CCID:
515 case DCCP_SOCKOPT_RX_CCID:
516 case DCCP_SOCKOPT_TX_CCID:
517 return dccp_setsockopt_ccid(sk, optname, optval, optlen);
518 }
519
520 if (optlen < (int)sizeof(int))
521 return -EINVAL;
522
523 if (get_user(val, (int __user *)optval))
524 return -EFAULT;
525
526 if (optname == DCCP_SOCKOPT_SERVICE)
527 return dccp_setsockopt_service(sk, val, optval, optlen);
528
529 lock_sock(sk);
530 switch (optname) {
531 case DCCP_SOCKOPT_SERVER_TIMEWAIT:
532 if (dp->dccps_role != DCCP_ROLE_SERVER)
533 err = -EOPNOTSUPP;
534 else
535 dp->dccps_server_timewait = (val != 0);
536 break;
537 case DCCP_SOCKOPT_SEND_CSCOV:
538 err = dccp_setsockopt_cscov(sk, val, false);
539 break;
540 case DCCP_SOCKOPT_RECV_CSCOV:
541 err = dccp_setsockopt_cscov(sk, val, true);
542 break;
543 case DCCP_SOCKOPT_QPOLICY_ID:
544 if (sk->sk_state != DCCP_CLOSED)
545 err = -EISCONN;
546 else if (val < 0 || val >= DCCPQ_POLICY_MAX)
547 err = -EINVAL;
548 else
549 dp->dccps_qpolicy = val;
550 break;
551 case DCCP_SOCKOPT_QPOLICY_TXQLEN:
552 if (val < 0)
553 err = -EINVAL;
554 else
555 dp->dccps_tx_qlen = val;
556 break;
557 default:
558 err = -ENOPROTOOPT;
559 break;
560 }
561 release_sock(sk);
562
563 return err;
564 }
565
dccp_setsockopt(struct sock * sk,int level,int optname,char __user * optval,unsigned int optlen)566 int dccp_setsockopt(struct sock *sk, int level, int optname,
567 char __user *optval, unsigned int optlen)
568 {
569 if (level != SOL_DCCP)
570 return inet_csk(sk)->icsk_af_ops->setsockopt(sk, level,
571 optname, optval,
572 optlen);
573 return do_dccp_setsockopt(sk, level, optname, optval, optlen);
574 }
575
576 EXPORT_SYMBOL_GPL(dccp_setsockopt);
577
578 #ifdef CONFIG_COMPAT
compat_dccp_setsockopt(struct sock * sk,int level,int optname,char __user * optval,unsigned int optlen)579 int compat_dccp_setsockopt(struct sock *sk, int level, int optname,
580 char __user *optval, unsigned int optlen)
581 {
582 if (level != SOL_DCCP)
583 return inet_csk_compat_setsockopt(sk, level, optname,
584 optval, optlen);
585 return do_dccp_setsockopt(sk, level, optname, optval, optlen);
586 }
587
588 EXPORT_SYMBOL_GPL(compat_dccp_setsockopt);
589 #endif
590
dccp_getsockopt_service(struct sock * sk,int len,__be32 __user * optval,int __user * optlen)591 static int dccp_getsockopt_service(struct sock *sk, int len,
592 __be32 __user *optval,
593 int __user *optlen)
594 {
595 const struct dccp_sock *dp = dccp_sk(sk);
596 const struct dccp_service_list *sl;
597 int err = -ENOENT, slen = 0, total_len = sizeof(u32);
598
599 lock_sock(sk);
600 if ((sl = dp->dccps_service_list) != NULL) {
601 slen = sl->dccpsl_nr * sizeof(u32);
602 total_len += slen;
603 }
604
605 err = -EINVAL;
606 if (total_len > len)
607 goto out;
608
609 err = 0;
610 if (put_user(total_len, optlen) ||
611 put_user(dp->dccps_service, optval) ||
612 (sl != NULL && copy_to_user(optval + 1, sl->dccpsl_list, slen)))
613 err = -EFAULT;
614 out:
615 release_sock(sk);
616 return err;
617 }
618
do_dccp_getsockopt(struct sock * sk,int level,int optname,char __user * optval,int __user * optlen)619 static int do_dccp_getsockopt(struct sock *sk, int level, int optname,
620 char __user *optval, int __user *optlen)
621 {
622 struct dccp_sock *dp;
623 int val, len;
624
625 if (get_user(len, optlen))
626 return -EFAULT;
627
628 if (len < (int)sizeof(int))
629 return -EINVAL;
630
631 dp = dccp_sk(sk);
632
633 switch (optname) {
634 case DCCP_SOCKOPT_PACKET_SIZE:
635 DCCP_WARN("sockopt(PACKET_SIZE) is deprecated: fix your app\n");
636 return 0;
637 case DCCP_SOCKOPT_SERVICE:
638 return dccp_getsockopt_service(sk, len,
639 (__be32 __user *)optval, optlen);
640 case DCCP_SOCKOPT_GET_CUR_MPS:
641 val = dp->dccps_mss_cache;
642 break;
643 case DCCP_SOCKOPT_AVAILABLE_CCIDS:
644 return ccid_getsockopt_builtin_ccids(sk, len, optval, optlen);
645 case DCCP_SOCKOPT_TX_CCID:
646 val = ccid_get_current_tx_ccid(dp);
647 if (val < 0)
648 return -ENOPROTOOPT;
649 break;
650 case DCCP_SOCKOPT_RX_CCID:
651 val = ccid_get_current_rx_ccid(dp);
652 if (val < 0)
653 return -ENOPROTOOPT;
654 break;
655 case DCCP_SOCKOPT_SERVER_TIMEWAIT:
656 val = dp->dccps_server_timewait;
657 break;
658 case DCCP_SOCKOPT_SEND_CSCOV:
659 val = dp->dccps_pcslen;
660 break;
661 case DCCP_SOCKOPT_RECV_CSCOV:
662 val = dp->dccps_pcrlen;
663 break;
664 case DCCP_SOCKOPT_QPOLICY_ID:
665 val = dp->dccps_qpolicy;
666 break;
667 case DCCP_SOCKOPT_QPOLICY_TXQLEN:
668 val = dp->dccps_tx_qlen;
669 break;
670 case 128 ... 191:
671 return ccid_hc_rx_getsockopt(dp->dccps_hc_rx_ccid, sk, optname,
672 len, (u32 __user *)optval, optlen);
673 case 192 ... 255:
674 return ccid_hc_tx_getsockopt(dp->dccps_hc_tx_ccid, sk, optname,
675 len, (u32 __user *)optval, optlen);
676 default:
677 return -ENOPROTOOPT;
678 }
679
680 len = sizeof(val);
681 if (put_user(len, optlen) || copy_to_user(optval, &val, len))
682 return -EFAULT;
683
684 return 0;
685 }
686
dccp_getsockopt(struct sock * sk,int level,int optname,char __user * optval,int __user * optlen)687 int dccp_getsockopt(struct sock *sk, int level, int optname,
688 char __user *optval, int __user *optlen)
689 {
690 if (level != SOL_DCCP)
691 return inet_csk(sk)->icsk_af_ops->getsockopt(sk, level,
692 optname, optval,
693 optlen);
694 return do_dccp_getsockopt(sk, level, optname, optval, optlen);
695 }
696
697 EXPORT_SYMBOL_GPL(dccp_getsockopt);
698
699 #ifdef CONFIG_COMPAT
compat_dccp_getsockopt(struct sock * sk,int level,int optname,char __user * optval,int __user * optlen)700 int compat_dccp_getsockopt(struct sock *sk, int level, int optname,
701 char __user *optval, int __user *optlen)
702 {
703 if (level != SOL_DCCP)
704 return inet_csk_compat_getsockopt(sk, level, optname,
705 optval, optlen);
706 return do_dccp_getsockopt(sk, level, optname, optval, optlen);
707 }
708
709 EXPORT_SYMBOL_GPL(compat_dccp_getsockopt);
710 #endif
711
dccp_msghdr_parse(struct msghdr * msg,struct sk_buff * skb)712 static int dccp_msghdr_parse(struct msghdr *msg, struct sk_buff *skb)
713 {
714 struct cmsghdr *cmsg;
715
716 /*
717 * Assign an (opaque) qpolicy priority value to skb->priority.
718 *
719 * We are overloading this skb field for use with the qpolicy subystem.
720 * The skb->priority is normally used for the SO_PRIORITY option, which
721 * is initialised from sk_priority. Since the assignment of sk_priority
722 * to skb->priority happens later (on layer 3), we overload this field
723 * for use with queueing priorities as long as the skb is on layer 4.
724 * The default priority value (if nothing is set) is 0.
725 */
726 skb->priority = 0;
727
728 for_each_cmsghdr(cmsg, msg) {
729 if (!CMSG_OK(msg, cmsg))
730 return -EINVAL;
731
732 if (cmsg->cmsg_level != SOL_DCCP)
733 continue;
734
735 if (cmsg->cmsg_type <= DCCP_SCM_QPOLICY_MAX &&
736 !dccp_qpolicy_param_ok(skb->sk, cmsg->cmsg_type))
737 return -EINVAL;
738
739 switch (cmsg->cmsg_type) {
740 case DCCP_SCM_PRIORITY:
741 if (cmsg->cmsg_len != CMSG_LEN(sizeof(__u32)))
742 return -EINVAL;
743 skb->priority = *(__u32 *)CMSG_DATA(cmsg);
744 break;
745 default:
746 return -EINVAL;
747 }
748 }
749 return 0;
750 }
751
dccp_sendmsg(struct sock * sk,struct msghdr * msg,size_t len)752 int dccp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
753 {
754 const struct dccp_sock *dp = dccp_sk(sk);
755 const int flags = msg->msg_flags;
756 const int noblock = flags & MSG_DONTWAIT;
757 struct sk_buff *skb;
758 int rc, size;
759 long timeo;
760
761 trace_dccp_probe(sk, len);
762
763 if (len > dp->dccps_mss_cache)
764 return -EMSGSIZE;
765
766 lock_sock(sk);
767
768 if (dccp_qpolicy_full(sk)) {
769 rc = -EAGAIN;
770 goto out_release;
771 }
772
773 timeo = sock_sndtimeo(sk, noblock);
774
775 /*
776 * We have to use sk_stream_wait_connect here to set sk_write_pending,
777 * so that the trick in dccp_rcv_request_sent_state_process.
778 */
779 /* Wait for a connection to finish. */
780 if ((1 << sk->sk_state) & ~(DCCPF_OPEN | DCCPF_PARTOPEN))
781 if ((rc = sk_stream_wait_connect(sk, &timeo)) != 0)
782 goto out_release;
783
784 size = sk->sk_prot->max_header + len;
785 release_sock(sk);
786 skb = sock_alloc_send_skb(sk, size, noblock, &rc);
787 lock_sock(sk);
788 if (skb == NULL)
789 goto out_release;
790
791 if (sk->sk_state == DCCP_CLOSED) {
792 rc = -ENOTCONN;
793 goto out_discard;
794 }
795
796 skb_reserve(skb, sk->sk_prot->max_header);
797 rc = memcpy_from_msg(skb_put(skb, len), msg, len);
798 if (rc != 0)
799 goto out_discard;
800
801 rc = dccp_msghdr_parse(msg, skb);
802 if (rc != 0)
803 goto out_discard;
804
805 dccp_qpolicy_push(sk, skb);
806 /*
807 * The xmit_timer is set if the TX CCID is rate-based and will expire
808 * when congestion control permits to release further packets into the
809 * network. Window-based CCIDs do not use this timer.
810 */
811 if (!timer_pending(&dp->dccps_xmit_timer))
812 dccp_write_xmit(sk);
813 out_release:
814 release_sock(sk);
815 return rc ? : len;
816 out_discard:
817 kfree_skb(skb);
818 goto out_release;
819 }
820
821 EXPORT_SYMBOL_GPL(dccp_sendmsg);
822
dccp_recvmsg(struct sock * sk,struct msghdr * msg,size_t len,int nonblock,int flags,int * addr_len)823 int dccp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int nonblock,
824 int flags, int *addr_len)
825 {
826 const struct dccp_hdr *dh;
827 long timeo;
828
829 lock_sock(sk);
830
831 if (sk->sk_state == DCCP_LISTEN) {
832 len = -ENOTCONN;
833 goto out;
834 }
835
836 timeo = sock_rcvtimeo(sk, nonblock);
837
838 do {
839 struct sk_buff *skb = skb_peek(&sk->sk_receive_queue);
840
841 if (skb == NULL)
842 goto verify_sock_status;
843
844 dh = dccp_hdr(skb);
845
846 switch (dh->dccph_type) {
847 case DCCP_PKT_DATA:
848 case DCCP_PKT_DATAACK:
849 goto found_ok_skb;
850
851 case DCCP_PKT_CLOSE:
852 case DCCP_PKT_CLOSEREQ:
853 if (!(flags & MSG_PEEK))
854 dccp_finish_passive_close(sk);
855 /* fall through */
856 case DCCP_PKT_RESET:
857 dccp_pr_debug("found fin (%s) ok!\n",
858 dccp_packet_name(dh->dccph_type));
859 len = 0;
860 goto found_fin_ok;
861 default:
862 dccp_pr_debug("packet_type=%s\n",
863 dccp_packet_name(dh->dccph_type));
864 sk_eat_skb(sk, skb);
865 }
866 verify_sock_status:
867 if (sock_flag(sk, SOCK_DONE)) {
868 len = 0;
869 break;
870 }
871
872 if (sk->sk_err) {
873 len = sock_error(sk);
874 break;
875 }
876
877 if (sk->sk_shutdown & RCV_SHUTDOWN) {
878 len = 0;
879 break;
880 }
881
882 if (sk->sk_state == DCCP_CLOSED) {
883 if (!sock_flag(sk, SOCK_DONE)) {
884 /* This occurs when user tries to read
885 * from never connected socket.
886 */
887 len = -ENOTCONN;
888 break;
889 }
890 len = 0;
891 break;
892 }
893
894 if (!timeo) {
895 len = -EAGAIN;
896 break;
897 }
898
899 if (signal_pending(current)) {
900 len = sock_intr_errno(timeo);
901 break;
902 }
903
904 sk_wait_data(sk, &timeo, NULL);
905 continue;
906 found_ok_skb:
907 if (len > skb->len)
908 len = skb->len;
909 else if (len < skb->len)
910 msg->msg_flags |= MSG_TRUNC;
911
912 if (skb_copy_datagram_msg(skb, 0, msg, len)) {
913 /* Exception. Bailout! */
914 len = -EFAULT;
915 break;
916 }
917 if (flags & MSG_TRUNC)
918 len = skb->len;
919 found_fin_ok:
920 if (!(flags & MSG_PEEK))
921 sk_eat_skb(sk, skb);
922 break;
923 } while (1);
924 out:
925 release_sock(sk);
926 return len;
927 }
928
929 EXPORT_SYMBOL_GPL(dccp_recvmsg);
930
inet_dccp_listen(struct socket * sock,int backlog)931 int inet_dccp_listen(struct socket *sock, int backlog)
932 {
933 struct sock *sk = sock->sk;
934 unsigned char old_state;
935 int err;
936
937 lock_sock(sk);
938
939 err = -EINVAL;
940 if (sock->state != SS_UNCONNECTED || sock->type != SOCK_DCCP)
941 goto out;
942
943 old_state = sk->sk_state;
944 if (!((1 << old_state) & (DCCPF_CLOSED | DCCPF_LISTEN)))
945 goto out;
946
947 sk->sk_max_ack_backlog = backlog;
948 /* Really, if the socket is already in listen state
949 * we can only allow the backlog to be adjusted.
950 */
951 if (old_state != DCCP_LISTEN) {
952 /*
953 * FIXME: here it probably should be sk->sk_prot->listen_start
954 * see tcp_listen_start
955 */
956 err = dccp_listen_start(sk, backlog);
957 if (err)
958 goto out;
959 }
960 err = 0;
961
962 out:
963 release_sock(sk);
964 return err;
965 }
966
967 EXPORT_SYMBOL_GPL(inet_dccp_listen);
968
dccp_terminate_connection(struct sock * sk)969 static void dccp_terminate_connection(struct sock *sk)
970 {
971 u8 next_state = DCCP_CLOSED;
972
973 switch (sk->sk_state) {
974 case DCCP_PASSIVE_CLOSE:
975 case DCCP_PASSIVE_CLOSEREQ:
976 dccp_finish_passive_close(sk);
977 break;
978 case DCCP_PARTOPEN:
979 dccp_pr_debug("Stop PARTOPEN timer (%p)\n", sk);
980 inet_csk_clear_xmit_timer(sk, ICSK_TIME_DACK);
981 /* fall through */
982 case DCCP_OPEN:
983 dccp_send_close(sk, 1);
984
985 if (dccp_sk(sk)->dccps_role == DCCP_ROLE_SERVER &&
986 !dccp_sk(sk)->dccps_server_timewait)
987 next_state = DCCP_ACTIVE_CLOSEREQ;
988 else
989 next_state = DCCP_CLOSING;
990 /* fall through */
991 default:
992 dccp_set_state(sk, next_state);
993 }
994 }
995
dccp_close(struct sock * sk,long timeout)996 void dccp_close(struct sock *sk, long timeout)
997 {
998 struct dccp_sock *dp = dccp_sk(sk);
999 struct sk_buff *skb;
1000 u32 data_was_unread = 0;
1001 int state;
1002
1003 lock_sock(sk);
1004
1005 sk->sk_shutdown = SHUTDOWN_MASK;
1006
1007 if (sk->sk_state == DCCP_LISTEN) {
1008 dccp_set_state(sk, DCCP_CLOSED);
1009
1010 /* Special case. */
1011 inet_csk_listen_stop(sk);
1012
1013 goto adjudge_to_death;
1014 }
1015
1016 sk_stop_timer(sk, &dp->dccps_xmit_timer);
1017
1018 /*
1019 * We need to flush the recv. buffs. We do this only on the
1020 * descriptor close, not protocol-sourced closes, because the
1021 *reader process may not have drained the data yet!
1022 */
1023 while ((skb = __skb_dequeue(&sk->sk_receive_queue)) != NULL) {
1024 data_was_unread += skb->len;
1025 __kfree_skb(skb);
1026 }
1027
1028 /* If socket has been already reset kill it. */
1029 if (sk->sk_state == DCCP_CLOSED)
1030 goto adjudge_to_death;
1031
1032 if (data_was_unread) {
1033 /* Unread data was tossed, send an appropriate Reset Code */
1034 DCCP_WARN("ABORT with %u bytes unread\n", data_was_unread);
1035 dccp_send_reset(sk, DCCP_RESET_CODE_ABORTED);
1036 dccp_set_state(sk, DCCP_CLOSED);
1037 } else if (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime) {
1038 /* Check zero linger _after_ checking for unread data. */
1039 sk->sk_prot->disconnect(sk, 0);
1040 } else if (sk->sk_state != DCCP_CLOSED) {
1041 /*
1042 * Normal connection termination. May need to wait if there are
1043 * still packets in the TX queue that are delayed by the CCID.
1044 */
1045 dccp_flush_write_queue(sk, &timeout);
1046 dccp_terminate_connection(sk);
1047 }
1048
1049 /*
1050 * Flush write queue. This may be necessary in several cases:
1051 * - we have been closed by the peer but still have application data;
1052 * - abortive termination (unread data or zero linger time),
1053 * - normal termination but queue could not be flushed within time limit
1054 */
1055 __skb_queue_purge(&sk->sk_write_queue);
1056
1057 sk_stream_wait_close(sk, timeout);
1058
1059 adjudge_to_death:
1060 state = sk->sk_state;
1061 sock_hold(sk);
1062 sock_orphan(sk);
1063
1064 /*
1065 * It is the last release_sock in its life. It will remove backlog.
1066 */
1067 release_sock(sk);
1068 /*
1069 * Now socket is owned by kernel and we acquire BH lock
1070 * to finish close. No need to check for user refs.
1071 */
1072 local_bh_disable();
1073 bh_lock_sock(sk);
1074 WARN_ON(sock_owned_by_user(sk));
1075
1076 percpu_counter_inc(sk->sk_prot->orphan_count);
1077
1078 /* Have we already been destroyed by a softirq or backlog? */
1079 if (state != DCCP_CLOSED && sk->sk_state == DCCP_CLOSED)
1080 goto out;
1081
1082 if (sk->sk_state == DCCP_CLOSED)
1083 inet_csk_destroy_sock(sk);
1084
1085 /* Otherwise, socket is reprieved until protocol close. */
1086
1087 out:
1088 bh_unlock_sock(sk);
1089 local_bh_enable();
1090 sock_put(sk);
1091 }
1092
1093 EXPORT_SYMBOL_GPL(dccp_close);
1094
dccp_shutdown(struct sock * sk,int how)1095 void dccp_shutdown(struct sock *sk, int how)
1096 {
1097 dccp_pr_debug("called shutdown(%x)\n", how);
1098 }
1099
1100 EXPORT_SYMBOL_GPL(dccp_shutdown);
1101
dccp_mib_init(void)1102 static inline int __init dccp_mib_init(void)
1103 {
1104 dccp_statistics = alloc_percpu(struct dccp_mib);
1105 if (!dccp_statistics)
1106 return -ENOMEM;
1107 return 0;
1108 }
1109
dccp_mib_exit(void)1110 static inline void dccp_mib_exit(void)
1111 {
1112 free_percpu(dccp_statistics);
1113 }
1114
1115 static int thash_entries;
1116 module_param(thash_entries, int, 0444);
1117 MODULE_PARM_DESC(thash_entries, "Number of ehash buckets");
1118
1119 #ifdef CONFIG_IP_DCCP_DEBUG
1120 bool dccp_debug;
1121 module_param(dccp_debug, bool, 0644);
1122 MODULE_PARM_DESC(dccp_debug, "Enable debug messages");
1123
1124 EXPORT_SYMBOL_GPL(dccp_debug);
1125 #endif
1126
dccp_init(void)1127 static int __init dccp_init(void)
1128 {
1129 unsigned long goal;
1130 unsigned long nr_pages = totalram_pages();
1131 int ehash_order, bhash_order, i;
1132 int rc;
1133
1134 BUILD_BUG_ON(sizeof(struct dccp_skb_cb) >
1135 FIELD_SIZEOF(struct sk_buff, cb));
1136 rc = percpu_counter_init(&dccp_orphan_count, 0, GFP_KERNEL);
1137 if (rc)
1138 goto out_fail;
1139 inet_hashinfo_init(&dccp_hashinfo);
1140 rc = inet_hashinfo2_init_mod(&dccp_hashinfo);
1141 if (rc)
1142 goto out_fail;
1143 rc = -ENOBUFS;
1144 dccp_hashinfo.bind_bucket_cachep =
1145 kmem_cache_create("dccp_bind_bucket",
1146 sizeof(struct inet_bind_bucket), 0,
1147 SLAB_HWCACHE_ALIGN, NULL);
1148 if (!dccp_hashinfo.bind_bucket_cachep)
1149 goto out_free_percpu;
1150
1151 /*
1152 * Size and allocate the main established and bind bucket
1153 * hash tables.
1154 *
1155 * The methodology is similar to that of the buffer cache.
1156 */
1157 if (nr_pages >= (128 * 1024))
1158 goal = nr_pages >> (21 - PAGE_SHIFT);
1159 else
1160 goal = nr_pages >> (23 - PAGE_SHIFT);
1161
1162 if (thash_entries)
1163 goal = (thash_entries *
1164 sizeof(struct inet_ehash_bucket)) >> PAGE_SHIFT;
1165 for (ehash_order = 0; (1UL << ehash_order) < goal; ehash_order++)
1166 ;
1167 do {
1168 unsigned long hash_size = (1UL << ehash_order) * PAGE_SIZE /
1169 sizeof(struct inet_ehash_bucket);
1170
1171 while (hash_size & (hash_size - 1))
1172 hash_size--;
1173 dccp_hashinfo.ehash_mask = hash_size - 1;
1174 dccp_hashinfo.ehash = (struct inet_ehash_bucket *)
1175 __get_free_pages(GFP_ATOMIC|__GFP_NOWARN, ehash_order);
1176 } while (!dccp_hashinfo.ehash && --ehash_order > 0);
1177
1178 if (!dccp_hashinfo.ehash) {
1179 DCCP_CRIT("Failed to allocate DCCP established hash table");
1180 goto out_free_bind_bucket_cachep;
1181 }
1182
1183 for (i = 0; i <= dccp_hashinfo.ehash_mask; i++)
1184 INIT_HLIST_NULLS_HEAD(&dccp_hashinfo.ehash[i].chain, i);
1185
1186 if (inet_ehash_locks_alloc(&dccp_hashinfo))
1187 goto out_free_dccp_ehash;
1188
1189 bhash_order = ehash_order;
1190
1191 do {
1192 dccp_hashinfo.bhash_size = (1UL << bhash_order) * PAGE_SIZE /
1193 sizeof(struct inet_bind_hashbucket);
1194 if ((dccp_hashinfo.bhash_size > (64 * 1024)) &&
1195 bhash_order > 0)
1196 continue;
1197 dccp_hashinfo.bhash = (struct inet_bind_hashbucket *)
1198 __get_free_pages(GFP_ATOMIC|__GFP_NOWARN, bhash_order);
1199 } while (!dccp_hashinfo.bhash && --bhash_order >= 0);
1200
1201 if (!dccp_hashinfo.bhash) {
1202 DCCP_CRIT("Failed to allocate DCCP bind hash table");
1203 goto out_free_dccp_locks;
1204 }
1205
1206 for (i = 0; i < dccp_hashinfo.bhash_size; i++) {
1207 spin_lock_init(&dccp_hashinfo.bhash[i].lock);
1208 INIT_HLIST_HEAD(&dccp_hashinfo.bhash[i].chain);
1209 }
1210
1211 rc = dccp_mib_init();
1212 if (rc)
1213 goto out_free_dccp_bhash;
1214
1215 rc = dccp_ackvec_init();
1216 if (rc)
1217 goto out_free_dccp_mib;
1218
1219 rc = dccp_sysctl_init();
1220 if (rc)
1221 goto out_ackvec_exit;
1222
1223 rc = ccid_initialize_builtins();
1224 if (rc)
1225 goto out_sysctl_exit;
1226
1227 dccp_timestamping_init();
1228
1229 return 0;
1230
1231 out_sysctl_exit:
1232 dccp_sysctl_exit();
1233 out_ackvec_exit:
1234 dccp_ackvec_exit();
1235 out_free_dccp_mib:
1236 dccp_mib_exit();
1237 out_free_dccp_bhash:
1238 free_pages((unsigned long)dccp_hashinfo.bhash, bhash_order);
1239 out_free_dccp_locks:
1240 inet_ehash_locks_free(&dccp_hashinfo);
1241 out_free_dccp_ehash:
1242 free_pages((unsigned long)dccp_hashinfo.ehash, ehash_order);
1243 out_free_bind_bucket_cachep:
1244 kmem_cache_destroy(dccp_hashinfo.bind_bucket_cachep);
1245 out_free_percpu:
1246 percpu_counter_destroy(&dccp_orphan_count);
1247 out_fail:
1248 dccp_hashinfo.bhash = NULL;
1249 dccp_hashinfo.ehash = NULL;
1250 dccp_hashinfo.bind_bucket_cachep = NULL;
1251 return rc;
1252 }
1253
dccp_fini(void)1254 static void __exit dccp_fini(void)
1255 {
1256 ccid_cleanup_builtins();
1257 dccp_mib_exit();
1258 free_pages((unsigned long)dccp_hashinfo.bhash,
1259 get_order(dccp_hashinfo.bhash_size *
1260 sizeof(struct inet_bind_hashbucket)));
1261 free_pages((unsigned long)dccp_hashinfo.ehash,
1262 get_order((dccp_hashinfo.ehash_mask + 1) *
1263 sizeof(struct inet_ehash_bucket)));
1264 inet_ehash_locks_free(&dccp_hashinfo);
1265 kmem_cache_destroy(dccp_hashinfo.bind_bucket_cachep);
1266 dccp_ackvec_exit();
1267 dccp_sysctl_exit();
1268 percpu_counter_destroy(&dccp_orphan_count);
1269 }
1270
1271 module_init(dccp_init);
1272 module_exit(dccp_fini);
1273
1274 MODULE_LICENSE("GPL");
1275 MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@conectiva.com.br>");
1276 MODULE_DESCRIPTION("DCCP - Datagram Congestion Controlled Protocol");
1277