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1/*
2 * net/tipc/socket.c: TIPC socket API
3 *
4 * Copyright (c) 2001-2007, 2012-2014, Ericsson AB
5 * Copyright (c) 2004-2008, 2010-2013, Wind River Systems
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions are met:
10 *
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the names of the copyright holders nor the names of its
17 * contributors may be used to endorse or promote products derived from
18 * this software without specific prior written permission.
19 *
20 * Alternatively, this software may be distributed under the terms of the
21 * GNU General Public License ("GPL") version 2 as published by the Free
22 * Software Foundation.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
25 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
28 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
32 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
34 * POSSIBILITY OF SUCH DAMAGE.
35 */
36
37#include "core.h"
38#include "port.h"
39
40#include <linux/export.h>
41
42#define SS_LISTENING -1 /* socket is listening */
43#define SS_READY -2 /* socket is connectionless */
44
45#define CONN_TIMEOUT_DEFAULT 8000 /* default connect timeout = 8s */
46
47static int backlog_rcv(struct sock *sk, struct sk_buff *skb);
48static void tipc_data_ready(struct sock *sk);
49static void tipc_write_space(struct sock *sk);
50static int tipc_release(struct socket *sock);
51static int tipc_accept(struct socket *sock, struct socket *new_sock, int flags);
52
53static const struct proto_ops packet_ops;
54static const struct proto_ops stream_ops;
55static const struct proto_ops msg_ops;
56
57static struct proto tipc_proto;
58static struct proto tipc_proto_kern;
59
60/*
61 * Revised TIPC socket locking policy:
62 *
63 * Most socket operations take the standard socket lock when they start
64 * and hold it until they finish (or until they need to sleep). Acquiring
65 * this lock grants the owner exclusive access to the fields of the socket
66 * data structures, with the exception of the backlog queue. A few socket
67 * operations can be done without taking the socket lock because they only
68 * read socket information that never changes during the life of the socket.
69 *
70 * Socket operations may acquire the lock for the associated TIPC port if they
71 * need to perform an operation on the port. If any routine needs to acquire
72 * both the socket lock and the port lock it must take the socket lock first
73 * to avoid the risk of deadlock.
74 *
75 * The dispatcher handling incoming messages cannot grab the socket lock in
76 * the standard fashion, since invoked it runs at the BH level and cannot block.
77 * Instead, it checks to see if the socket lock is currently owned by someone,
78 * and either handles the message itself or adds it to the socket's backlog
79 * queue; in the latter case the queued message is processed once the process
80 * owning the socket lock releases it.
81 *
82 * NOTE: Releasing the socket lock while an operation is sleeping overcomes
83 * the problem of a blocked socket operation preventing any other operations
84 * from occurring. However, applications must be careful if they have
85 * multiple threads trying to send (or receive) on the same socket, as these
86 * operations might interfere with each other. For example, doing a connect
87 * and a receive at the same time might allow the receive to consume the
88 * ACK message meant for the connect. While additional work could be done
89 * to try and overcome this, it doesn't seem to be worthwhile at the present.
90 *
91 * NOTE: Releasing the socket lock while an operation is sleeping also ensures
92 * that another operation that must be performed in a non-blocking manner is
93 * not delayed for very long because the lock has already been taken.
94 *
95 * NOTE: This code assumes that certain fields of a port/socket pair are
96 * constant over its lifetime; such fields can be examined without taking
97 * the socket lock and/or port lock, and do not need to be re-read even
98 * after resuming processing after waiting. These fields include:
99 * - socket type
100 * - pointer to socket sk structure (aka tipc_sock structure)
101 * - pointer to port structure
102 * - port reference
103 */
104
105#include "socket.h"
106
107/**
108 * advance_rx_queue - discard first buffer in socket receive queue
109 *
110 * Caller must hold socket lock
111 */
112static void advance_rx_queue(struct sock *sk)
113{
114 kfree_skb(__skb_dequeue(&sk->sk_receive_queue));
115}
116
117/**
118 * reject_rx_queue - reject all buffers in socket receive queue
119 *
120 * Caller must hold socket lock
121 */
122static void reject_rx_queue(struct sock *sk)
123{
124 struct sk_buff *buf;
125
126 while ((buf = __skb_dequeue(&sk->sk_receive_queue)))
127 tipc_reject_msg(buf, TIPC_ERR_NO_PORT);
128}
129
130/**
131 * tipc_sk_create - create a TIPC socket
132 * @net: network namespace (must be default network)
133 * @sock: pre-allocated socket structure
134 * @protocol: protocol indicator (must be 0)
135 * @kern: caused by kernel or by userspace?
136 *
137 * This routine creates additional data structures used by the TIPC socket,
138 * initializes them, and links them together.
139 *
140 * Returns 0 on success, errno otherwise
141 */
142static int tipc_sk_create(struct net *net, struct socket *sock,
143 int protocol, int kern)
144{
145 const struct proto_ops *ops;
146 socket_state state;
147 struct sock *sk;
148 struct tipc_sock *tsk;
149 struct tipc_port *port;
150 u32 ref;
151
152 /* Validate arguments */
153 if (unlikely(protocol != 0))
154 return -EPROTONOSUPPORT;
155
156 switch (sock->type) {
157 case SOCK_STREAM:
158 ops = &stream_ops;
159 state = SS_UNCONNECTED;
160 break;
161 case SOCK_SEQPACKET:
162 ops = &packet_ops;
163 state = SS_UNCONNECTED;
164 break;
165 case SOCK_DGRAM:
166 case SOCK_RDM:
167 ops = &msg_ops;
168 state = SS_READY;
169 break;
170 default:
171 return -EPROTOTYPE;
172 }
173
174 /* Allocate socket's protocol area */
175 if (!kern)
176 sk = sk_alloc(net, AF_TIPC, GFP_KERNEL, &tipc_proto);
177 else
178 sk = sk_alloc(net, AF_TIPC, GFP_KERNEL, &tipc_proto_kern);
179
180 if (sk == NULL)
181 return -ENOMEM;
182
183 tsk = tipc_sk(sk);
184 port = &tsk->port;
185
186 ref = tipc_port_init(port, TIPC_LOW_IMPORTANCE);
187 if (!ref) {
188 pr_warn("Socket registration failed, ref. table exhausted\n");
189 sk_free(sk);
190 return -ENOMEM;
191 }
192
193 /* Finish initializing socket data structures */
194 sock->ops = ops;
195 sock->state = state;
196
197 sock_init_data(sock, sk);
198 sk->sk_backlog_rcv = backlog_rcv;
199 sk->sk_rcvbuf = sysctl_tipc_rmem[1];
200 sk->sk_data_ready = tipc_data_ready;
201 sk->sk_write_space = tipc_write_space;
202 tipc_sk(sk)->conn_timeout = CONN_TIMEOUT_DEFAULT;
203 tipc_port_unlock(port);
204
205 if (sock->state == SS_READY) {
206 tipc_port_set_unreturnable(port, true);
207 if (sock->type == SOCK_DGRAM)
208 tipc_port_set_unreliable(port, true);
209 }
210 return 0;
211}
212
213/**
214 * tipc_sock_create_local - create TIPC socket from inside TIPC module
215 * @type: socket type - SOCK_RDM or SOCK_SEQPACKET
216 *
217 * We cannot use sock_creat_kern here because it bumps module user count.
218 * Since socket owner and creator is the same module we must make sure
219 * that module count remains zero for module local sockets, otherwise
220 * we cannot do rmmod.
221 *
222 * Returns 0 on success, errno otherwise
223 */
224int tipc_sock_create_local(int type, struct socket **res)
225{
226 int rc;
227
228 rc = sock_create_lite(AF_TIPC, type, 0, res);
229 if (rc < 0) {
230 pr_err("Failed to create kernel socket\n");
231 return rc;
232 }
233 tipc_sk_create(&init_net, *res, 0, 1);
234
235 return 0;
236}
237
238/**
239 * tipc_sock_release_local - release socket created by tipc_sock_create_local
240 * @sock: the socket to be released.
241 *
242 * Module reference count is not incremented when such sockets are created,
243 * so we must keep it from being decremented when they are released.
244 */
245void tipc_sock_release_local(struct socket *sock)
246{
247 tipc_release(sock);
248 sock->ops = NULL;
249 sock_release(sock);
250}
251
252/**
253 * tipc_sock_accept_local - accept a connection on a socket created
254 * with tipc_sock_create_local. Use this function to avoid that
255 * module reference count is inadvertently incremented.
256 *
257 * @sock: the accepting socket
258 * @newsock: reference to the new socket to be created
259 * @flags: socket flags
260 */
261
262int tipc_sock_accept_local(struct socket *sock, struct socket **newsock,
263 int flags)
264{
265 struct sock *sk = sock->sk;
266 int ret;
267
268 ret = sock_create_lite(sk->sk_family, sk->sk_type,
269 sk->sk_protocol, newsock);
270 if (ret < 0)
271 return ret;
272
273 ret = tipc_accept(sock, *newsock, flags);
274 if (ret < 0) {
275 sock_release(*newsock);
276 return ret;
277 }
278 (*newsock)->ops = sock->ops;
279 return ret;
280}
281
282/**
283 * tipc_release - destroy a TIPC socket
284 * @sock: socket to destroy
285 *
286 * This routine cleans up any messages that are still queued on the socket.
287 * For DGRAM and RDM socket types, all queued messages are rejected.
288 * For SEQPACKET and STREAM socket types, the first message is rejected
289 * and any others are discarded. (If the first message on a STREAM socket
290 * is partially-read, it is discarded and the next one is rejected instead.)
291 *
292 * NOTE: Rejected messages are not necessarily returned to the sender! They
293 * are returned or discarded according to the "destination droppable" setting
294 * specified for the message by the sender.
295 *
296 * Returns 0 on success, errno otherwise
297 */
298static int tipc_release(struct socket *sock)
299{
300 struct sock *sk = sock->sk;
301 struct tipc_sock *tsk;
302 struct tipc_port *port;
303 struct sk_buff *buf;
304
305 /*
306 * Exit if socket isn't fully initialized (occurs when a failed accept()
307 * releases a pre-allocated child socket that was never used)
308 */
309 if (sk == NULL)
310 return 0;
311
312 tsk = tipc_sk(sk);
313 port = &tsk->port;
314 lock_sock(sk);
315
316 /*
317 * Reject all unreceived messages, except on an active connection
318 * (which disconnects locally & sends a 'FIN+' to peer)
319 */
320 while (sock->state != SS_DISCONNECTING) {
321 buf = __skb_dequeue(&sk->sk_receive_queue);
322 if (buf == NULL)
323 break;
324 if (TIPC_SKB_CB(buf)->handle != NULL)
325 kfree_skb(buf);
326 else {
327 if ((sock->state == SS_CONNECTING) ||
328 (sock->state == SS_CONNECTED)) {
329 sock->state = SS_DISCONNECTING;
330 tipc_port_disconnect(port->ref);
331 }
332 tipc_reject_msg(buf, TIPC_ERR_NO_PORT);
333 }
334 }
335
336 /* Destroy TIPC port; also disconnects an active connection and
337 * sends a 'FIN-' to peer.
338 */
339 tipc_port_destroy(port);
340
341 /* Discard any remaining (connection-based) messages in receive queue */
342 __skb_queue_purge(&sk->sk_receive_queue);
343
344 /* Reject any messages that accumulated in backlog queue */
345 sock->state = SS_DISCONNECTING;
346 release_sock(sk);
347
348 sock_put(sk);
349 sock->sk = NULL;
350
351 return 0;
352}
353
354/**
355 * tipc_bind - associate or disassocate TIPC name(s) with a socket
356 * @sock: socket structure
357 * @uaddr: socket address describing name(s) and desired operation
358 * @uaddr_len: size of socket address data structure
359 *
360 * Name and name sequence binding is indicated using a positive scope value;
361 * a negative scope value unbinds the specified name. Specifying no name
362 * (i.e. a socket address length of 0) unbinds all names from the socket.
363 *
364 * Returns 0 on success, errno otherwise
365 *
366 * NOTE: This routine doesn't need to take the socket lock since it doesn't
367 * access any non-constant socket information.
368 */
369static int tipc_bind(struct socket *sock, struct sockaddr *uaddr,
370 int uaddr_len)
371{
372 struct sock *sk = sock->sk;
373 struct sockaddr_tipc *addr = (struct sockaddr_tipc *)uaddr;
374 struct tipc_sock *tsk = tipc_sk(sk);
375 int res = -EINVAL;
376
377 lock_sock(sk);
378 if (unlikely(!uaddr_len)) {
379 res = tipc_withdraw(&tsk->port, 0, NULL);
380 goto exit;
381 }
382
383 if (uaddr_len < sizeof(struct sockaddr_tipc)) {
384 res = -EINVAL;
385 goto exit;
386 }
387 if (addr->family != AF_TIPC) {
388 res = -EAFNOSUPPORT;
389 goto exit;
390 }
391
392 if (addr->addrtype == TIPC_ADDR_NAME)
393 addr->addr.nameseq.upper = addr->addr.nameseq.lower;
394 else if (addr->addrtype != TIPC_ADDR_NAMESEQ) {
395 res = -EAFNOSUPPORT;
396 goto exit;
397 }
398
399 if ((addr->addr.nameseq.type < TIPC_RESERVED_TYPES) &&
400 (addr->addr.nameseq.type != TIPC_TOP_SRV) &&
401 (addr->addr.nameseq.type != TIPC_CFG_SRV)) {
402 res = -EACCES;
403 goto exit;
404 }
405
406 res = (addr->scope > 0) ?
407 tipc_publish(&tsk->port, addr->scope, &addr->addr.nameseq) :
408 tipc_withdraw(&tsk->port, -addr->scope, &addr->addr.nameseq);
409exit:
410 release_sock(sk);
411 return res;
412}
413
414/**
415 * tipc_getname - get port ID of socket or peer socket
416 * @sock: socket structure
417 * @uaddr: area for returned socket address
418 * @uaddr_len: area for returned length of socket address
419 * @peer: 0 = own ID, 1 = current peer ID, 2 = current/former peer ID
420 *
421 * Returns 0 on success, errno otherwise
422 *
423 * NOTE: This routine doesn't need to take the socket lock since it only
424 * accesses socket information that is unchanging (or which changes in
425 * a completely predictable manner).
426 */
427static int tipc_getname(struct socket *sock, struct sockaddr *uaddr,
428 int *uaddr_len, int peer)
429{
430 struct sockaddr_tipc *addr = (struct sockaddr_tipc *)uaddr;
431 struct tipc_sock *tsk = tipc_sk(sock->sk);
432
433 memset(addr, 0, sizeof(*addr));
434 if (peer) {
435 if ((sock->state != SS_CONNECTED) &&
436 ((peer != 2) || (sock->state != SS_DISCONNECTING)))
437 return -ENOTCONN;
438 addr->addr.id.ref = tipc_port_peerport(&tsk->port);
439 addr->addr.id.node = tipc_port_peernode(&tsk->port);
440 } else {
441 addr->addr.id.ref = tsk->port.ref;
442 addr->addr.id.node = tipc_own_addr;
443 }
444
445 *uaddr_len = sizeof(*addr);
446 addr->addrtype = TIPC_ADDR_ID;
447 addr->family = AF_TIPC;
448 addr->scope = 0;
449 addr->addr.name.domain = 0;
450
451 return 0;
452}
453
454/**
455 * tipc_poll - read and possibly block on pollmask
456 * @file: file structure associated with the socket
457 * @sock: socket for which to calculate the poll bits
458 * @wait: ???
459 *
460 * Returns pollmask value
461 *
462 * COMMENTARY:
463 * It appears that the usual socket locking mechanisms are not useful here
464 * since the pollmask info is potentially out-of-date the moment this routine
465 * exits. TCP and other protocols seem to rely on higher level poll routines
466 * to handle any preventable race conditions, so TIPC will do the same ...
467 *
468 * TIPC sets the returned events as follows:
469 *
470 * socket state flags set
471 * ------------ ---------
472 * unconnected no read flags
473 * POLLOUT if port is not congested
474 *
475 * connecting POLLIN/POLLRDNORM if ACK/NACK in rx queue
476 * no write flags
477 *
478 * connected POLLIN/POLLRDNORM if data in rx queue
479 * POLLOUT if port is not congested
480 *
481 * disconnecting POLLIN/POLLRDNORM/POLLHUP
482 * no write flags
483 *
484 * listening POLLIN if SYN in rx queue
485 * no write flags
486 *
487 * ready POLLIN/POLLRDNORM if data in rx queue
488 * [connectionless] POLLOUT (since port cannot be congested)
489 *
490 * IMPORTANT: The fact that a read or write operation is indicated does NOT
491 * imply that the operation will succeed, merely that it should be performed
492 * and will not block.
493 */
494static unsigned int tipc_poll(struct file *file, struct socket *sock,
495 poll_table *wait)
496{
497 struct sock *sk = sock->sk;
498 struct tipc_sock *tsk = tipc_sk(sk);
499 u32 mask = 0;
500
501 sock_poll_wait(file, sk_sleep(sk), wait);
502
503 switch ((int)sock->state) {
504 case SS_UNCONNECTED:
505 if (!tsk->port.congested)
506 mask |= POLLOUT;
507 break;
508 case SS_READY:
509 case SS_CONNECTED:
510 if (!tsk->port.congested)
511 mask |= POLLOUT;
512 /* fall thru' */
513 case SS_CONNECTING:
514 case SS_LISTENING:
515 if (!skb_queue_empty(&sk->sk_receive_queue))
516 mask |= (POLLIN | POLLRDNORM);
517 break;
518 case SS_DISCONNECTING:
519 mask = (POLLIN | POLLRDNORM | POLLHUP);
520 break;
521 }
522
523 return mask;
524}
525
526/**
527 * dest_name_check - verify user is permitted to send to specified port name
528 * @dest: destination address
529 * @m: descriptor for message to be sent
530 *
531 * Prevents restricted configuration commands from being issued by
532 * unauthorized users.
533 *
534 * Returns 0 if permission is granted, otherwise errno
535 */
536static int dest_name_check(struct sockaddr_tipc *dest, struct msghdr *m)
537{
538 struct tipc_cfg_msg_hdr hdr;
539
540 if (likely(dest->addr.name.name.type >= TIPC_RESERVED_TYPES))
541 return 0;
542 if (likely(dest->addr.name.name.type == TIPC_TOP_SRV))
543 return 0;
544 if (likely(dest->addr.name.name.type != TIPC_CFG_SRV))
545 return -EACCES;
546
547 if (!m->msg_iovlen || (m->msg_iov[0].iov_len < sizeof(hdr)))
548 return -EMSGSIZE;
549 if (copy_from_user(&hdr, m->msg_iov[0].iov_base, sizeof(hdr)))
550 return -EFAULT;
551 if ((ntohs(hdr.tcm_type) & 0xC000) && (!capable(CAP_NET_ADMIN)))
552 return -EACCES;
553
554 return 0;
555}
556
557static int tipc_wait_for_sndmsg(struct socket *sock, long *timeo_p)
558{
559 struct sock *sk = sock->sk;
560 struct tipc_sock *tsk = tipc_sk(sk);
561 DEFINE_WAIT(wait);
562 int done;
563
564 do {
565 int err = sock_error(sk);
566 if (err)
567 return err;
568 if (sock->state == SS_DISCONNECTING)
569 return -EPIPE;
570 if (!*timeo_p)
571 return -EAGAIN;
572 if (signal_pending(current))
573 return sock_intr_errno(*timeo_p);
574
575 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
576 done = sk_wait_event(sk, timeo_p, !tsk->port.congested);
577 finish_wait(sk_sleep(sk), &wait);
578 } while (!done);
579 return 0;
580}
581
582
583/**
584 * tipc_sendmsg - send message in connectionless manner
585 * @iocb: if NULL, indicates that socket lock is already held
586 * @sock: socket structure
587 * @m: message to send
588 * @total_len: length of message
589 *
590 * Message must have an destination specified explicitly.
591 * Used for SOCK_RDM and SOCK_DGRAM messages,
592 * and for 'SYN' messages on SOCK_SEQPACKET and SOCK_STREAM connections.
593 * (Note: 'SYN+' is prohibited on SOCK_STREAM.)
594 *
595 * Returns the number of bytes sent on success, or errno otherwise
596 */
597static int tipc_sendmsg(struct kiocb *iocb, struct socket *sock,
598 struct msghdr *m, size_t total_len)
599{
600 struct sock *sk = sock->sk;
601 struct tipc_sock *tsk = tipc_sk(sk);
602 struct tipc_port *port = &tsk->port;
603 DECLARE_SOCKADDR(struct sockaddr_tipc *, dest, m->msg_name);
604 int needs_conn;
605 long timeo;
606 int res = -EINVAL;
607
608 if (unlikely(!dest))
609 return -EDESTADDRREQ;
610 if (unlikely((m->msg_namelen < sizeof(*dest)) ||
611 (dest->family != AF_TIPC)))
612 return -EINVAL;
613 if (total_len > TIPC_MAX_USER_MSG_SIZE)
614 return -EMSGSIZE;
615
616 if (iocb)
617 lock_sock(sk);
618
619 needs_conn = (sock->state != SS_READY);
620 if (unlikely(needs_conn)) {
621 if (sock->state == SS_LISTENING) {
622 res = -EPIPE;
623 goto exit;
624 }
625 if (sock->state != SS_UNCONNECTED) {
626 res = -EISCONN;
627 goto exit;
628 }
629 if (tsk->port.published) {
630 res = -EOPNOTSUPP;
631 goto exit;
632 }
633 if (dest->addrtype == TIPC_ADDR_NAME) {
634 tsk->port.conn_type = dest->addr.name.name.type;
635 tsk->port.conn_instance = dest->addr.name.name.instance;
636 }
637
638 /* Abort any pending connection attempts (very unlikely) */
639 reject_rx_queue(sk);
640 }
641
642 timeo = sock_sndtimeo(sk, m->msg_flags & MSG_DONTWAIT);
643 do {
644 if (dest->addrtype == TIPC_ADDR_NAME) {
645 res = dest_name_check(dest, m);
646 if (res)
647 break;
648 res = tipc_send2name(port,
649 &dest->addr.name.name,
650 dest->addr.name.domain,
651 m->msg_iov,
652 total_len);
653 } else if (dest->addrtype == TIPC_ADDR_ID) {
654 res = tipc_send2port(port,
655 &dest->addr.id,
656 m->msg_iov,
657 total_len);
658 } else if (dest->addrtype == TIPC_ADDR_MCAST) {
659 if (needs_conn) {
660 res = -EOPNOTSUPP;
661 break;
662 }
663 res = dest_name_check(dest, m);
664 if (res)
665 break;
666 res = tipc_port_mcast_xmit(port,
667 &dest->addr.nameseq,
668 m->msg_iov,
669 total_len);
670 }
671 if (likely(res != -ELINKCONG)) {
672 if (needs_conn && (res >= 0))
673 sock->state = SS_CONNECTING;
674 break;
675 }
676 res = tipc_wait_for_sndmsg(sock, &timeo);
677 if (res)
678 break;
679 } while (1);
680
681exit:
682 if (iocb)
683 release_sock(sk);
684 return res;
685}
686
687static int tipc_wait_for_sndpkt(struct socket *sock, long *timeo_p)
688{
689 struct sock *sk = sock->sk;
690 struct tipc_sock *tsk = tipc_sk(sk);
691 struct tipc_port *port = &tsk->port;
692 DEFINE_WAIT(wait);
693 int done;
694
695 do {
696 int err = sock_error(sk);
697 if (err)
698 return err;
699 if (sock->state == SS_DISCONNECTING)
700 return -EPIPE;
701 else if (sock->state != SS_CONNECTED)
702 return -ENOTCONN;
703 if (!*timeo_p)
704 return -EAGAIN;
705 if (signal_pending(current))
706 return sock_intr_errno(*timeo_p);
707
708 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
709 done = sk_wait_event(sk, timeo_p,
710 (!port->congested || !port->connected));
711 finish_wait(sk_sleep(sk), &wait);
712 } while (!done);
713 return 0;
714}
715
716/**
717 * tipc_send_packet - send a connection-oriented message
718 * @iocb: if NULL, indicates that socket lock is already held
719 * @sock: socket structure
720 * @m: message to send
721 * @total_len: length of message
722 *
723 * Used for SOCK_SEQPACKET messages and SOCK_STREAM data.
724 *
725 * Returns the number of bytes sent on success, or errno otherwise
726 */
727static int tipc_send_packet(struct kiocb *iocb, struct socket *sock,
728 struct msghdr *m, size_t total_len)
729{
730 struct sock *sk = sock->sk;
731 struct tipc_sock *tsk = tipc_sk(sk);
732 DECLARE_SOCKADDR(struct sockaddr_tipc *, dest, m->msg_name);
733 int res = -EINVAL;
734 long timeo;
735
736 /* Handle implied connection establishment */
737 if (unlikely(dest))
738 return tipc_sendmsg(iocb, sock, m, total_len);
739
740 if (total_len > TIPC_MAX_USER_MSG_SIZE)
741 return -EMSGSIZE;
742
743 if (iocb)
744 lock_sock(sk);
745
746 if (unlikely(sock->state != SS_CONNECTED)) {
747 if (sock->state == SS_DISCONNECTING)
748 res = -EPIPE;
749 else
750 res = -ENOTCONN;
751 goto exit;
752 }
753
754 timeo = sock_sndtimeo(sk, m->msg_flags & MSG_DONTWAIT);
755 do {
756 res = tipc_send(&tsk->port, m->msg_iov, total_len);
757 if (likely(res != -ELINKCONG))
758 break;
759 res = tipc_wait_for_sndpkt(sock, &timeo);
760 if (res)
761 break;
762 } while (1);
763exit:
764 if (iocb)
765 release_sock(sk);
766 return res;
767}
768
769/**
770 * tipc_send_stream - send stream-oriented data
771 * @iocb: (unused)
772 * @sock: socket structure
773 * @m: data to send
774 * @total_len: total length of data to be sent
775 *
776 * Used for SOCK_STREAM data.
777 *
778 * Returns the number of bytes sent on success (or partial success),
779 * or errno if no data sent
780 */
781static int tipc_send_stream(struct kiocb *iocb, struct socket *sock,
782 struct msghdr *m, size_t total_len)
783{
784 struct sock *sk = sock->sk;
785 struct tipc_sock *tsk = tipc_sk(sk);
786 struct msghdr my_msg;
787 struct iovec my_iov;
788 struct iovec *curr_iov;
789 int curr_iovlen;
790 char __user *curr_start;
791 u32 hdr_size;
792 int curr_left;
793 int bytes_to_send;
794 int bytes_sent;
795 int res;
796
797 lock_sock(sk);
798
799 /* Handle special cases where there is no connection */
800 if (unlikely(sock->state != SS_CONNECTED)) {
801 if (sock->state == SS_UNCONNECTED)
802 res = tipc_send_packet(NULL, sock, m, total_len);
803 else
804 res = sock->state == SS_DISCONNECTING ? -EPIPE : -ENOTCONN;
805 goto exit;
806 }
807
808 if (unlikely(m->msg_name)) {
809 res = -EISCONN;
810 goto exit;
811 }
812
813 if (total_len > (unsigned int)INT_MAX) {
814 res = -EMSGSIZE;
815 goto exit;
816 }
817
818 /*
819 * Send each iovec entry using one or more messages
820 *
821 * Note: This algorithm is good for the most likely case
822 * (i.e. one large iovec entry), but could be improved to pass sets
823 * of small iovec entries into send_packet().
824 */
825 curr_iov = m->msg_iov;
826 curr_iovlen = m->msg_iovlen;
827 my_msg.msg_iov = &my_iov;
828 my_msg.msg_iovlen = 1;
829 my_msg.msg_flags = m->msg_flags;
830 my_msg.msg_name = NULL;
831 bytes_sent = 0;
832
833 hdr_size = msg_hdr_sz(&tsk->port.phdr);
834
835 while (curr_iovlen--) {
836 curr_start = curr_iov->iov_base;
837 curr_left = curr_iov->iov_len;
838
839 while (curr_left) {
840 bytes_to_send = tsk->port.max_pkt - hdr_size;
841 if (bytes_to_send > TIPC_MAX_USER_MSG_SIZE)
842 bytes_to_send = TIPC_MAX_USER_MSG_SIZE;
843 if (curr_left < bytes_to_send)
844 bytes_to_send = curr_left;
845 my_iov.iov_base = curr_start;
846 my_iov.iov_len = bytes_to_send;
847 res = tipc_send_packet(NULL, sock, &my_msg,
848 bytes_to_send);
849 if (res < 0) {
850 if (bytes_sent)
851 res = bytes_sent;
852 goto exit;
853 }
854 curr_left -= bytes_to_send;
855 curr_start += bytes_to_send;
856 bytes_sent += bytes_to_send;
857 }
858
859 curr_iov++;
860 }
861 res = bytes_sent;
862exit:
863 release_sock(sk);
864 return res;
865}
866
867/**
868 * auto_connect - complete connection setup to a remote port
869 * @tsk: tipc socket structure
870 * @msg: peer's response message
871 *
872 * Returns 0 on success, errno otherwise
873 */
874static int auto_connect(struct tipc_sock *tsk, struct tipc_msg *msg)
875{
876 struct tipc_port *port = &tsk->port;
877 struct socket *sock = tsk->sk.sk_socket;
878 struct tipc_portid peer;
879
880 peer.ref = msg_origport(msg);
881 peer.node = msg_orignode(msg);
882
883 __tipc_port_connect(port->ref, port, &peer);
884
885 if (msg_importance(msg) > TIPC_CRITICAL_IMPORTANCE)
886 return -EINVAL;
887 msg_set_importance(&port->phdr, (u32)msg_importance(msg));
888 sock->state = SS_CONNECTED;
889 return 0;
890}
891
892/**
893 * set_orig_addr - capture sender's address for received message
894 * @m: descriptor for message info
895 * @msg: received message header
896 *
897 * Note: Address is not captured if not requested by receiver.
898 */
899static void set_orig_addr(struct msghdr *m, struct tipc_msg *msg)
900{
901 DECLARE_SOCKADDR(struct sockaddr_tipc *, addr, m->msg_name);
902
903 if (addr) {
904 addr->family = AF_TIPC;
905 addr->addrtype = TIPC_ADDR_ID;
906 memset(&addr->addr, 0, sizeof(addr->addr));
907 addr->addr.id.ref = msg_origport(msg);
908 addr->addr.id.node = msg_orignode(msg);
909 addr->addr.name.domain = 0; /* could leave uninitialized */
910 addr->scope = 0; /* could leave uninitialized */
911 m->msg_namelen = sizeof(struct sockaddr_tipc);
912 }
913}
914
915/**
916 * anc_data_recv - optionally capture ancillary data for received message
917 * @m: descriptor for message info
918 * @msg: received message header
919 * @tport: TIPC port associated with message
920 *
921 * Note: Ancillary data is not captured if not requested by receiver.
922 *
923 * Returns 0 if successful, otherwise errno
924 */
925static int anc_data_recv(struct msghdr *m, struct tipc_msg *msg,
926 struct tipc_port *tport)
927{
928 u32 anc_data[3];
929 u32 err;
930 u32 dest_type;
931 int has_name;
932 int res;
933
934 if (likely(m->msg_controllen == 0))
935 return 0;
936
937 /* Optionally capture errored message object(s) */
938 err = msg ? msg_errcode(msg) : 0;
939 if (unlikely(err)) {
940 anc_data[0] = err;
941 anc_data[1] = msg_data_sz(msg);
942 res = put_cmsg(m, SOL_TIPC, TIPC_ERRINFO, 8, anc_data);
943 if (res)
944 return res;
945 if (anc_data[1]) {
946 res = put_cmsg(m, SOL_TIPC, TIPC_RETDATA, anc_data[1],
947 msg_data(msg));
948 if (res)
949 return res;
950 }
951 }
952
953 /* Optionally capture message destination object */
954 dest_type = msg ? msg_type(msg) : TIPC_DIRECT_MSG;
955 switch (dest_type) {
956 case TIPC_NAMED_MSG:
957 has_name = 1;
958 anc_data[0] = msg_nametype(msg);
959 anc_data[1] = msg_namelower(msg);
960 anc_data[2] = msg_namelower(msg);
961 break;
962 case TIPC_MCAST_MSG:
963 has_name = 1;
964 anc_data[0] = msg_nametype(msg);
965 anc_data[1] = msg_namelower(msg);
966 anc_data[2] = msg_nameupper(msg);
967 break;
968 case TIPC_CONN_MSG:
969 has_name = (tport->conn_type != 0);
970 anc_data[0] = tport->conn_type;
971 anc_data[1] = tport->conn_instance;
972 anc_data[2] = tport->conn_instance;
973 break;
974 default:
975 has_name = 0;
976 }
977 if (has_name) {
978 res = put_cmsg(m, SOL_TIPC, TIPC_DESTNAME, 12, anc_data);
979 if (res)
980 return res;
981 }
982
983 return 0;
984}
985
986static int tipc_wait_for_rcvmsg(struct socket *sock, long timeo)
987{
988 struct sock *sk = sock->sk;
989 DEFINE_WAIT(wait);
990 int err;
991
992 for (;;) {
993 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
994 if (timeo && skb_queue_empty(&sk->sk_receive_queue)) {
995 if (sock->state == SS_DISCONNECTING) {
996 err = -ENOTCONN;
997 break;
998 }
999 release_sock(sk);
1000 timeo = schedule_timeout(timeo);
1001 lock_sock(sk);
1002 }
1003 err = 0;
1004 if (!skb_queue_empty(&sk->sk_receive_queue))
1005 break;
1006 err = sock_intr_errno(timeo);
1007 if (signal_pending(current))
1008 break;
1009 err = -EAGAIN;
1010 if (!timeo)
1011 break;
1012 }
1013 finish_wait(sk_sleep(sk), &wait);
1014 return err;
1015}
1016
1017/**
1018 * tipc_recvmsg - receive packet-oriented message
1019 * @iocb: (unused)
1020 * @m: descriptor for message info
1021 * @buf_len: total size of user buffer area
1022 * @flags: receive flags
1023 *
1024 * Used for SOCK_DGRAM, SOCK_RDM, and SOCK_SEQPACKET messages.
1025 * If the complete message doesn't fit in user area, truncate it.
1026 *
1027 * Returns size of returned message data, errno otherwise
1028 */
1029static int tipc_recvmsg(struct kiocb *iocb, struct socket *sock,
1030 struct msghdr *m, size_t buf_len, int flags)
1031{
1032 struct sock *sk = sock->sk;
1033 struct tipc_sock *tsk = tipc_sk(sk);
1034 struct tipc_port *port = &tsk->port;
1035 struct sk_buff *buf;
1036 struct tipc_msg *msg;
1037 long timeo;
1038 unsigned int sz;
1039 u32 err;
1040 int res;
1041
1042 /* Catch invalid receive requests */
1043 if (unlikely(!buf_len))
1044 return -EINVAL;
1045
1046 lock_sock(sk);
1047
1048 if (unlikely(sock->state == SS_UNCONNECTED)) {
1049 res = -ENOTCONN;
1050 goto exit;
1051 }
1052
1053 timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
1054restart:
1055
1056 /* Look for a message in receive queue; wait if necessary */
1057 res = tipc_wait_for_rcvmsg(sock, timeo);
1058 if (res)
1059 goto exit;
1060
1061 /* Look at first message in receive queue */
1062 buf = skb_peek(&sk->sk_receive_queue);
1063 msg = buf_msg(buf);
1064 sz = msg_data_sz(msg);
1065 err = msg_errcode(msg);
1066
1067 /* Discard an empty non-errored message & try again */
1068 if ((!sz) && (!err)) {
1069 advance_rx_queue(sk);
1070 goto restart;
1071 }
1072
1073 /* Capture sender's address (optional) */
1074 set_orig_addr(m, msg);
1075
1076 /* Capture ancillary data (optional) */
1077 res = anc_data_recv(m, msg, port);
1078 if (res)
1079 goto exit;
1080
1081 /* Capture message data (if valid) & compute return value (always) */
1082 if (!err) {
1083 if (unlikely(buf_len < sz)) {
1084 sz = buf_len;
1085 m->msg_flags |= MSG_TRUNC;
1086 }
1087 res = skb_copy_datagram_iovec(buf, msg_hdr_sz(msg),
1088 m->msg_iov, sz);
1089 if (res)
1090 goto exit;
1091 res = sz;
1092 } else {
1093 if ((sock->state == SS_READY) ||
1094 ((err == TIPC_CONN_SHUTDOWN) || m->msg_control))
1095 res = 0;
1096 else
1097 res = -ECONNRESET;
1098 }
1099
1100 /* Consume received message (optional) */
1101 if (likely(!(flags & MSG_PEEK))) {
1102 if ((sock->state != SS_READY) &&
1103 (++port->conn_unacked >= TIPC_FLOW_CONTROL_WIN))
1104 tipc_acknowledge(port->ref, port->conn_unacked);
1105 advance_rx_queue(sk);
1106 }
1107exit:
1108 release_sock(sk);
1109 return res;
1110}
1111
1112/**
1113 * tipc_recv_stream - receive stream-oriented data
1114 * @iocb: (unused)
1115 * @m: descriptor for message info
1116 * @buf_len: total size of user buffer area
1117 * @flags: receive flags
1118 *
1119 * Used for SOCK_STREAM messages only. If not enough data is available
1120 * will optionally wait for more; never truncates data.
1121 *
1122 * Returns size of returned message data, errno otherwise
1123 */
1124static int tipc_recv_stream(struct kiocb *iocb, struct socket *sock,
1125 struct msghdr *m, size_t buf_len, int flags)
1126{
1127 struct sock *sk = sock->sk;
1128 struct tipc_sock *tsk = tipc_sk(sk);
1129 struct tipc_port *port = &tsk->port;
1130 struct sk_buff *buf;
1131 struct tipc_msg *msg;
1132 long timeo;
1133 unsigned int sz;
1134 int sz_to_copy, target, needed;
1135 int sz_copied = 0;
1136 u32 err;
1137 int res = 0;
1138
1139 /* Catch invalid receive attempts */
1140 if (unlikely(!buf_len))
1141 return -EINVAL;
1142
1143 lock_sock(sk);
1144
1145 if (unlikely(sock->state == SS_UNCONNECTED)) {
1146 res = -ENOTCONN;
1147 goto exit;
1148 }
1149
1150 target = sock_rcvlowat(sk, flags & MSG_WAITALL, buf_len);
1151 timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
1152
1153restart:
1154 /* Look for a message in receive queue; wait if necessary */
1155 res = tipc_wait_for_rcvmsg(sock, timeo);
1156 if (res)
1157 goto exit;
1158
1159 /* Look at first message in receive queue */
1160 buf = skb_peek(&sk->sk_receive_queue);
1161 msg = buf_msg(buf);
1162 sz = msg_data_sz(msg);
1163 err = msg_errcode(msg);
1164
1165 /* Discard an empty non-errored message & try again */
1166 if ((!sz) && (!err)) {
1167 advance_rx_queue(sk);
1168 goto restart;
1169 }
1170
1171 /* Optionally capture sender's address & ancillary data of first msg */
1172 if (sz_copied == 0) {
1173 set_orig_addr(m, msg);
1174 res = anc_data_recv(m, msg, port);
1175 if (res)
1176 goto exit;
1177 }
1178
1179 /* Capture message data (if valid) & compute return value (always) */
1180 if (!err) {
1181 u32 offset = (u32)(unsigned long)(TIPC_SKB_CB(buf)->handle);
1182
1183 sz -= offset;
1184 needed = (buf_len - sz_copied);
1185 sz_to_copy = (sz <= needed) ? sz : needed;
1186
1187 res = skb_copy_datagram_iovec(buf, msg_hdr_sz(msg) + offset,
1188 m->msg_iov, sz_to_copy);
1189 if (res)
1190 goto exit;
1191
1192 sz_copied += sz_to_copy;
1193
1194 if (sz_to_copy < sz) {
1195 if (!(flags & MSG_PEEK))
1196 TIPC_SKB_CB(buf)->handle =
1197 (void *)(unsigned long)(offset + sz_to_copy);
1198 goto exit;
1199 }
1200 } else {
1201 if (sz_copied != 0)
1202 goto exit; /* can't add error msg to valid data */
1203
1204 if ((err == TIPC_CONN_SHUTDOWN) || m->msg_control)
1205 res = 0;
1206 else
1207 res = -ECONNRESET;
1208 }
1209
1210 /* Consume received message (optional) */
1211 if (likely(!(flags & MSG_PEEK))) {
1212 if (unlikely(++port->conn_unacked >= TIPC_FLOW_CONTROL_WIN))
1213 tipc_acknowledge(port->ref, port->conn_unacked);
1214 advance_rx_queue(sk);
1215 }
1216
1217 /* Loop around if more data is required */
1218 if ((sz_copied < buf_len) && /* didn't get all requested data */
1219 (!skb_queue_empty(&sk->sk_receive_queue) ||
1220 (sz_copied < target)) && /* and more is ready or required */
1221 (!(flags & MSG_PEEK)) && /* and aren't just peeking at data */
1222 (!err)) /* and haven't reached a FIN */
1223 goto restart;
1224
1225exit:
1226 release_sock(sk);
1227 return sz_copied ? sz_copied : res;
1228}
1229
1230/**
1231 * tipc_write_space - wake up thread if port congestion is released
1232 * @sk: socket
1233 */
1234static void tipc_write_space(struct sock *sk)
1235{
1236 struct socket_wq *wq;
1237
1238 rcu_read_lock();
1239 wq = rcu_dereference(sk->sk_wq);
1240 if (wq_has_sleeper(wq))
1241 wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
1242 POLLWRNORM | POLLWRBAND);
1243 rcu_read_unlock();
1244}
1245
1246/**
1247 * tipc_data_ready - wake up threads to indicate messages have been received
1248 * @sk: socket
1249 * @len: the length of messages
1250 */
1251static void tipc_data_ready(struct sock *sk)
1252{
1253 struct socket_wq *wq;
1254
1255 rcu_read_lock();
1256 wq = rcu_dereference(sk->sk_wq);
1257 if (wq_has_sleeper(wq))
1258 wake_up_interruptible_sync_poll(&wq->wait, POLLIN |
1259 POLLRDNORM | POLLRDBAND);
1260 rcu_read_unlock();
1261}
1262
1263/**
1264 * filter_connect - Handle all incoming messages for a connection-based socket
1265 * @tsk: TIPC socket
1266 * @msg: message
1267 *
1268 * Returns TIPC error status code and socket error status code
1269 * once it encounters some errors
1270 */
1271static u32 filter_connect(struct tipc_sock *tsk, struct sk_buff **buf)
1272{
1273 struct sock *sk = &tsk->sk;
1274 struct tipc_port *port = &tsk->port;
1275 struct socket *sock = sk->sk_socket;
1276 struct tipc_msg *msg = buf_msg(*buf);
1277
1278 u32 retval = TIPC_ERR_NO_PORT;
1279 int res;
1280
1281 if (msg_mcast(msg))
1282 return retval;
1283
1284 switch ((int)sock->state) {
1285 case SS_CONNECTED:
1286 /* Accept only connection-based messages sent by peer */
1287 if (msg_connected(msg) && tipc_port_peer_msg(port, msg)) {
1288 if (unlikely(msg_errcode(msg))) {
1289 sock->state = SS_DISCONNECTING;
1290 __tipc_port_disconnect(port);
1291 }
1292 retval = TIPC_OK;
1293 }
1294 break;
1295 case SS_CONNECTING:
1296 /* Accept only ACK or NACK message */
1297 if (unlikely(msg_errcode(msg))) {
1298 sock->state = SS_DISCONNECTING;
1299 sk->sk_err = ECONNREFUSED;
1300 retval = TIPC_OK;
1301 break;
1302 }
1303
1304 if (unlikely(!msg_connected(msg)))
1305 break;
1306
1307 res = auto_connect(tsk, msg);
1308 if (res) {
1309 sock->state = SS_DISCONNECTING;
1310 sk->sk_err = -res;
1311 retval = TIPC_OK;
1312 break;
1313 }
1314
1315 /* If an incoming message is an 'ACK-', it should be
1316 * discarded here because it doesn't contain useful
1317 * data. In addition, we should try to wake up
1318 * connect() routine if sleeping.
1319 */
1320 if (msg_data_sz(msg) == 0) {
1321 kfree_skb(*buf);
1322 *buf = NULL;
1323 if (waitqueue_active(sk_sleep(sk)))
1324 wake_up_interruptible(sk_sleep(sk));
1325 }
1326 retval = TIPC_OK;
1327 break;
1328 case SS_LISTENING:
1329 case SS_UNCONNECTED:
1330 /* Accept only SYN message */
1331 if (!msg_connected(msg) && !(msg_errcode(msg)))
1332 retval = TIPC_OK;
1333 break;
1334 case SS_DISCONNECTING:
1335 break;
1336 default:
1337 pr_err("Unknown socket state %u\n", sock->state);
1338 }
1339 return retval;
1340}
1341
1342/**
1343 * rcvbuf_limit - get proper overload limit of socket receive queue
1344 * @sk: socket
1345 * @buf: message
1346 *
1347 * For all connection oriented messages, irrespective of importance,
1348 * the default overload value (i.e. 67MB) is set as limit.
1349 *
1350 * For all connectionless messages, by default new queue limits are
1351 * as belows:
1352 *
1353 * TIPC_LOW_IMPORTANCE (4 MB)
1354 * TIPC_MEDIUM_IMPORTANCE (8 MB)
1355 * TIPC_HIGH_IMPORTANCE (16 MB)
1356 * TIPC_CRITICAL_IMPORTANCE (32 MB)
1357 *
1358 * Returns overload limit according to corresponding message importance
1359 */
1360static unsigned int rcvbuf_limit(struct sock *sk, struct sk_buff *buf)
1361{
1362 struct tipc_msg *msg = buf_msg(buf);
1363
1364 if (msg_connected(msg))
1365 return sysctl_tipc_rmem[2];
1366
1367 return sk->sk_rcvbuf >> TIPC_CRITICAL_IMPORTANCE <<
1368 msg_importance(msg);
1369}
1370
1371/**
1372 * filter_rcv - validate incoming message
1373 * @sk: socket
1374 * @buf: message
1375 *
1376 * Enqueues message on receive queue if acceptable; optionally handles
1377 * disconnect indication for a connected socket.
1378 *
1379 * Called with socket lock already taken; port lock may also be taken.
1380 *
1381 * Returns TIPC error status code (TIPC_OK if message is not to be rejected)
1382 */
1383static u32 filter_rcv(struct sock *sk, struct sk_buff *buf)
1384{
1385 struct socket *sock = sk->sk_socket;
1386 struct tipc_sock *tsk = tipc_sk(sk);
1387 struct tipc_msg *msg = buf_msg(buf);
1388 unsigned int limit = rcvbuf_limit(sk, buf);
1389 u32 res = TIPC_OK;
1390
1391 /* Reject message if it is wrong sort of message for socket */
1392 if (msg_type(msg) > TIPC_DIRECT_MSG)
1393 return TIPC_ERR_NO_PORT;
1394
1395 if (sock->state == SS_READY) {
1396 if (msg_connected(msg))
1397 return TIPC_ERR_NO_PORT;
1398 } else {
1399 res = filter_connect(tsk, &buf);
1400 if (res != TIPC_OK || buf == NULL)
1401 return res;
1402 }
1403
1404 /* Reject message if there isn't room to queue it */
1405 if (sk_rmem_alloc_get(sk) + buf->truesize >= limit)
1406 return TIPC_ERR_OVERLOAD;
1407
1408 /* Enqueue message */
1409 TIPC_SKB_CB(buf)->handle = NULL;
1410 __skb_queue_tail(&sk->sk_receive_queue, buf);
1411 skb_set_owner_r(buf, sk);
1412
1413 sk->sk_data_ready(sk);
1414 return TIPC_OK;
1415}
1416
1417/**
1418 * backlog_rcv - handle incoming message from backlog queue
1419 * @sk: socket
1420 * @buf: message
1421 *
1422 * Caller must hold socket lock, but not port lock.
1423 *
1424 * Returns 0
1425 */
1426static int backlog_rcv(struct sock *sk, struct sk_buff *buf)
1427{
1428 u32 res;
1429
1430 res = filter_rcv(sk, buf);
1431 if (res)
1432 tipc_reject_msg(buf, res);
1433 return 0;
1434}
1435
1436/**
1437 * tipc_sk_rcv - handle incoming message
1438 * @sk: socket receiving message
1439 * @buf: message
1440 *
1441 * Called with port lock already taken.
1442 *
1443 * Returns TIPC error status code (TIPC_OK if message is not to be rejected)
1444 */
1445u32 tipc_sk_rcv(struct sock *sk, struct sk_buff *buf)
1446{
1447 u32 res;
1448
1449 /*
1450 * Process message if socket is unlocked; otherwise add to backlog queue
1451 *
1452 * This code is based on sk_receive_skb(), but must be distinct from it
1453 * since a TIPC-specific filter/reject mechanism is utilized
1454 */
1455 bh_lock_sock(sk);
1456 if (!sock_owned_by_user(sk)) {
1457 res = filter_rcv(sk, buf);
1458 } else {
1459 if (sk_add_backlog(sk, buf, rcvbuf_limit(sk, buf)))
1460 res = TIPC_ERR_OVERLOAD;
1461 else
1462 res = TIPC_OK;
1463 }
1464 bh_unlock_sock(sk);
1465
1466 return res;
1467}
1468
1469static int tipc_wait_for_connect(struct socket *sock, long *timeo_p)
1470{
1471 struct sock *sk = sock->sk;
1472 DEFINE_WAIT(wait);
1473 int done;
1474
1475 do {
1476 int err = sock_error(sk);
1477 if (err)
1478 return err;
1479 if (!*timeo_p)
1480 return -ETIMEDOUT;
1481 if (signal_pending(current))
1482 return sock_intr_errno(*timeo_p);
1483
1484 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1485 done = sk_wait_event(sk, timeo_p, sock->state != SS_CONNECTING);
1486 finish_wait(sk_sleep(sk), &wait);
1487 } while (!done);
1488 return 0;
1489}
1490
1491/**
1492 * tipc_connect - establish a connection to another TIPC port
1493 * @sock: socket structure
1494 * @dest: socket address for destination port
1495 * @destlen: size of socket address data structure
1496 * @flags: file-related flags associated with socket
1497 *
1498 * Returns 0 on success, errno otherwise
1499 */
1500static int tipc_connect(struct socket *sock, struct sockaddr *dest,
1501 int destlen, int flags)
1502{
1503 struct sock *sk = sock->sk;
1504 struct sockaddr_tipc *dst = (struct sockaddr_tipc *)dest;
1505 struct msghdr m = {NULL,};
1506 long timeout = (flags & O_NONBLOCK) ? 0 : tipc_sk(sk)->conn_timeout;
1507 socket_state previous;
1508 int res;
1509
1510 lock_sock(sk);
1511
1512 /* For now, TIPC does not allow use of connect() with DGRAM/RDM types */
1513 if (sock->state == SS_READY) {
1514 res = -EOPNOTSUPP;
1515 goto exit;
1516 }
1517
1518 /*
1519 * Reject connection attempt using multicast address
1520 *
1521 * Note: send_msg() validates the rest of the address fields,
1522 * so there's no need to do it here
1523 */
1524 if (dst->addrtype == TIPC_ADDR_MCAST) {
1525 res = -EINVAL;
1526 goto exit;
1527 }
1528
1529 previous = sock->state;
1530 switch (sock->state) {
1531 case SS_UNCONNECTED:
1532 /* Send a 'SYN-' to destination */
1533 m.msg_name = dest;
1534 m.msg_namelen = destlen;
1535
1536 /* If connect is in non-blocking case, set MSG_DONTWAIT to
1537 * indicate send_msg() is never blocked.
1538 */
1539 if (!timeout)
1540 m.msg_flags = MSG_DONTWAIT;
1541
1542 res = tipc_sendmsg(NULL, sock, &m, 0);
1543 if ((res < 0) && (res != -EWOULDBLOCK))
1544 goto exit;
1545
1546 /* Just entered SS_CONNECTING state; the only
1547 * difference is that return value in non-blocking
1548 * case is EINPROGRESS, rather than EALREADY.
1549 */
1550 res = -EINPROGRESS;
1551 case SS_CONNECTING:
1552 if (previous == SS_CONNECTING)
1553 res = -EALREADY;
1554 if (!timeout)
1555 goto exit;
1556 timeout = msecs_to_jiffies(timeout);
1557 /* Wait until an 'ACK' or 'RST' arrives, or a timeout occurs */
1558 res = tipc_wait_for_connect(sock, &timeout);
1559 break;
1560 case SS_CONNECTED:
1561 res = -EISCONN;
1562 break;
1563 default:
1564 res = -EINVAL;
1565 break;
1566 }
1567exit:
1568 release_sock(sk);
1569 return res;
1570}
1571
1572/**
1573 * tipc_listen - allow socket to listen for incoming connections
1574 * @sock: socket structure
1575 * @len: (unused)
1576 *
1577 * Returns 0 on success, errno otherwise
1578 */
1579static int tipc_listen(struct socket *sock, int len)
1580{
1581 struct sock *sk = sock->sk;
1582 int res;
1583
1584 lock_sock(sk);
1585
1586 if (sock->state != SS_UNCONNECTED)
1587 res = -EINVAL;
1588 else {
1589 sock->state = SS_LISTENING;
1590 res = 0;
1591 }
1592
1593 release_sock(sk);
1594 return res;
1595}
1596
1597static int tipc_wait_for_accept(struct socket *sock, long timeo)
1598{
1599 struct sock *sk = sock->sk;
1600 DEFINE_WAIT(wait);
1601 int err;
1602
1603 /* True wake-one mechanism for incoming connections: only
1604 * one process gets woken up, not the 'whole herd'.
1605 * Since we do not 'race & poll' for established sockets
1606 * anymore, the common case will execute the loop only once.
1607 */
1608 for (;;) {
1609 prepare_to_wait_exclusive(sk_sleep(sk), &wait,
1610 TASK_INTERRUPTIBLE);
1611 if (timeo && skb_queue_empty(&sk->sk_receive_queue)) {
1612 release_sock(sk);
1613 timeo = schedule_timeout(timeo);
1614 lock_sock(sk);
1615 }
1616 err = 0;
1617 if (!skb_queue_empty(&sk->sk_receive_queue))
1618 break;
1619 err = -EINVAL;
1620 if (sock->state != SS_LISTENING)
1621 break;
1622 err = sock_intr_errno(timeo);
1623 if (signal_pending(current))
1624 break;
1625 err = -EAGAIN;
1626 if (!timeo)
1627 break;
1628 }
1629 finish_wait(sk_sleep(sk), &wait);
1630 return err;
1631}
1632
1633/**
1634 * tipc_accept - wait for connection request
1635 * @sock: listening socket
1636 * @newsock: new socket that is to be connected
1637 * @flags: file-related flags associated with socket
1638 *
1639 * Returns 0 on success, errno otherwise
1640 */
1641static int tipc_accept(struct socket *sock, struct socket *new_sock, int flags)
1642{
1643 struct sock *new_sk, *sk = sock->sk;
1644 struct sk_buff *buf;
1645 struct tipc_port *new_port;
1646 struct tipc_msg *msg;
1647 struct tipc_portid peer;
1648 u32 new_ref;
1649 long timeo;
1650 int res;
1651
1652 lock_sock(sk);
1653
1654 if (sock->state != SS_LISTENING) {
1655 res = -EINVAL;
1656 goto exit;
1657 }
1658 timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
1659 res = tipc_wait_for_accept(sock, timeo);
1660 if (res)
1661 goto exit;
1662
1663 buf = skb_peek(&sk->sk_receive_queue);
1664
1665 res = tipc_sk_create(sock_net(sock->sk), new_sock, 0, 1);
1666 if (res)
1667 goto exit;
1668
1669 new_sk = new_sock->sk;
1670 new_port = &tipc_sk(new_sk)->port;
1671 new_ref = new_port->ref;
1672 msg = buf_msg(buf);
1673
1674 /* we lock on new_sk; but lockdep sees the lock on sk */
1675 lock_sock_nested(new_sk, SINGLE_DEPTH_NESTING);
1676
1677 /*
1678 * Reject any stray messages received by new socket
1679 * before the socket lock was taken (very, very unlikely)
1680 */
1681 reject_rx_queue(new_sk);
1682
1683 /* Connect new socket to it's peer */
1684 peer.ref = msg_origport(msg);
1685 peer.node = msg_orignode(msg);
1686 tipc_port_connect(new_ref, &peer);
1687 new_sock->state = SS_CONNECTED;
1688
1689 tipc_port_set_importance(new_port, msg_importance(msg));
1690 if (msg_named(msg)) {
1691 new_port->conn_type = msg_nametype(msg);
1692 new_port->conn_instance = msg_nameinst(msg);
1693 }
1694
1695 /*
1696 * Respond to 'SYN-' by discarding it & returning 'ACK'-.
1697 * Respond to 'SYN+' by queuing it on new socket.
1698 */
1699 if (!msg_data_sz(msg)) {
1700 struct msghdr m = {NULL,};
1701
1702 advance_rx_queue(sk);
1703 tipc_send_packet(NULL, new_sock, &m, 0);
1704 } else {
1705 __skb_dequeue(&sk->sk_receive_queue);
1706 __skb_queue_head(&new_sk->sk_receive_queue, buf);
1707 skb_set_owner_r(buf, new_sk);
1708 }
1709 release_sock(new_sk);
1710exit:
1711 release_sock(sk);
1712 return res;
1713}
1714
1715/**
1716 * tipc_shutdown - shutdown socket connection
1717 * @sock: socket structure
1718 * @how: direction to close (must be SHUT_RDWR)
1719 *
1720 * Terminates connection (if necessary), then purges socket's receive queue.
1721 *
1722 * Returns 0 on success, errno otherwise
1723 */
1724static int tipc_shutdown(struct socket *sock, int how)
1725{
1726 struct sock *sk = sock->sk;
1727 struct tipc_sock *tsk = tipc_sk(sk);
1728 struct tipc_port *port = &tsk->port;
1729 struct sk_buff *buf;
1730 int res;
1731
1732 if (how != SHUT_RDWR)
1733 return -EINVAL;
1734
1735 lock_sock(sk);
1736
1737 switch (sock->state) {
1738 case SS_CONNECTING:
1739 case SS_CONNECTED:
1740
1741restart:
1742 /* Disconnect and send a 'FIN+' or 'FIN-' message to peer */
1743 buf = __skb_dequeue(&sk->sk_receive_queue);
1744 if (buf) {
1745 if (TIPC_SKB_CB(buf)->handle != NULL) {
1746 kfree_skb(buf);
1747 goto restart;
1748 }
1749 tipc_port_disconnect(port->ref);
1750 tipc_reject_msg(buf, TIPC_CONN_SHUTDOWN);
1751 } else {
1752 tipc_port_shutdown(port->ref);
1753 }
1754
1755 sock->state = SS_DISCONNECTING;
1756
1757 /* fall through */
1758
1759 case SS_DISCONNECTING:
1760
1761 /* Discard any unreceived messages */
1762 __skb_queue_purge(&sk->sk_receive_queue);
1763
1764 /* Wake up anyone sleeping in poll */
1765 sk->sk_state_change(sk);
1766 res = 0;
1767 break;
1768
1769 default:
1770 res = -ENOTCONN;
1771 }
1772
1773 release_sock(sk);
1774 return res;
1775}
1776
1777/**
1778 * tipc_setsockopt - set socket option
1779 * @sock: socket structure
1780 * @lvl: option level
1781 * @opt: option identifier
1782 * @ov: pointer to new option value
1783 * @ol: length of option value
1784 *
1785 * For stream sockets only, accepts and ignores all IPPROTO_TCP options
1786 * (to ease compatibility).
1787 *
1788 * Returns 0 on success, errno otherwise
1789 */
1790static int tipc_setsockopt(struct socket *sock, int lvl, int opt,
1791 char __user *ov, unsigned int ol)
1792{
1793 struct sock *sk = sock->sk;
1794 struct tipc_sock *tsk = tipc_sk(sk);
1795 struct tipc_port *port = &tsk->port;
1796 u32 value;
1797 int res;
1798
1799 if ((lvl == IPPROTO_TCP) && (sock->type == SOCK_STREAM))
1800 return 0;
1801 if (lvl != SOL_TIPC)
1802 return -ENOPROTOOPT;
1803 if (ol < sizeof(value))
1804 return -EINVAL;
1805 res = get_user(value, (u32 __user *)ov);
1806 if (res)
1807 return res;
1808
1809 lock_sock(sk);
1810
1811 switch (opt) {
1812 case TIPC_IMPORTANCE:
1813 tipc_port_set_importance(port, value);
1814 break;
1815 case TIPC_SRC_DROPPABLE:
1816 if (sock->type != SOCK_STREAM)
1817 tipc_port_set_unreliable(port, value);
1818 else
1819 res = -ENOPROTOOPT;
1820 break;
1821 case TIPC_DEST_DROPPABLE:
1822 tipc_port_set_unreturnable(port, value);
1823 break;
1824 case TIPC_CONN_TIMEOUT:
1825 tipc_sk(sk)->conn_timeout = value;
1826 /* no need to set "res", since already 0 at this point */
1827 break;
1828 default:
1829 res = -EINVAL;
1830 }
1831
1832 release_sock(sk);
1833
1834 return res;
1835}
1836
1837/**
1838 * tipc_getsockopt - get socket option
1839 * @sock: socket structure
1840 * @lvl: option level
1841 * @opt: option identifier
1842 * @ov: receptacle for option value
1843 * @ol: receptacle for length of option value
1844 *
1845 * For stream sockets only, returns 0 length result for all IPPROTO_TCP options
1846 * (to ease compatibility).
1847 *
1848 * Returns 0 on success, errno otherwise
1849 */
1850static int tipc_getsockopt(struct socket *sock, int lvl, int opt,
1851 char __user *ov, int __user *ol)
1852{
1853 struct sock *sk = sock->sk;
1854 struct tipc_sock *tsk = tipc_sk(sk);
1855 struct tipc_port *port = &tsk->port;
1856 int len;
1857 u32 value;
1858 int res;
1859
1860 if ((lvl == IPPROTO_TCP) && (sock->type == SOCK_STREAM))
1861 return put_user(0, ol);
1862 if (lvl != SOL_TIPC)
1863 return -ENOPROTOOPT;
1864 res = get_user(len, ol);
1865 if (res)
1866 return res;
1867
1868 lock_sock(sk);
1869
1870 switch (opt) {
1871 case TIPC_IMPORTANCE:
1872 value = tipc_port_importance(port);
1873 break;
1874 case TIPC_SRC_DROPPABLE:
1875 value = tipc_port_unreliable(port);
1876 break;
1877 case TIPC_DEST_DROPPABLE:
1878 value = tipc_port_unreturnable(port);
1879 break;
1880 case TIPC_CONN_TIMEOUT:
1881 value = tipc_sk(sk)->conn_timeout;
1882 /* no need to set "res", since already 0 at this point */
1883 break;
1884 case TIPC_NODE_RECVQ_DEPTH:
1885 value = 0; /* was tipc_queue_size, now obsolete */
1886 break;
1887 case TIPC_SOCK_RECVQ_DEPTH:
1888 value = skb_queue_len(&sk->sk_receive_queue);
1889 break;
1890 default:
1891 res = -EINVAL;
1892 }
1893
1894 release_sock(sk);
1895
1896 if (res)
1897 return res; /* "get" failed */
1898
1899 if (len < sizeof(value))
1900 return -EINVAL;
1901
1902 if (copy_to_user(ov, &value, sizeof(value)))
1903 return -EFAULT;
1904
1905 return put_user(sizeof(value), ol);
1906}
1907
1908/* Protocol switches for the various types of TIPC sockets */
1909
1910static const struct proto_ops msg_ops = {
1911 .owner = THIS_MODULE,
1912 .family = AF_TIPC,
1913 .release = tipc_release,
1914 .bind = tipc_bind,
1915 .connect = tipc_connect,
1916 .socketpair = sock_no_socketpair,
1917 .accept = sock_no_accept,
1918 .getname = tipc_getname,
1919 .poll = tipc_poll,
1920 .ioctl = sock_no_ioctl,
1921 .listen = sock_no_listen,
1922 .shutdown = tipc_shutdown,
1923 .setsockopt = tipc_setsockopt,
1924 .getsockopt = tipc_getsockopt,
1925 .sendmsg = tipc_sendmsg,
1926 .recvmsg = tipc_recvmsg,
1927 .mmap = sock_no_mmap,
1928 .sendpage = sock_no_sendpage
1929};
1930
1931static const struct proto_ops packet_ops = {
1932 .owner = THIS_MODULE,
1933 .family = AF_TIPC,
1934 .release = tipc_release,
1935 .bind = tipc_bind,
1936 .connect = tipc_connect,
1937 .socketpair = sock_no_socketpair,
1938 .accept = tipc_accept,
1939 .getname = tipc_getname,
1940 .poll = tipc_poll,
1941 .ioctl = sock_no_ioctl,
1942 .listen = tipc_listen,
1943 .shutdown = tipc_shutdown,
1944 .setsockopt = tipc_setsockopt,
1945 .getsockopt = tipc_getsockopt,
1946 .sendmsg = tipc_send_packet,
1947 .recvmsg = tipc_recvmsg,
1948 .mmap = sock_no_mmap,
1949 .sendpage = sock_no_sendpage
1950};
1951
1952static const struct proto_ops stream_ops = {
1953 .owner = THIS_MODULE,
1954 .family = AF_TIPC,
1955 .release = tipc_release,
1956 .bind = tipc_bind,
1957 .connect = tipc_connect,
1958 .socketpair = sock_no_socketpair,
1959 .accept = tipc_accept,
1960 .getname = tipc_getname,
1961 .poll = tipc_poll,
1962 .ioctl = sock_no_ioctl,
1963 .listen = tipc_listen,
1964 .shutdown = tipc_shutdown,
1965 .setsockopt = tipc_setsockopt,
1966 .getsockopt = tipc_getsockopt,
1967 .sendmsg = tipc_send_stream,
1968 .recvmsg = tipc_recv_stream,
1969 .mmap = sock_no_mmap,
1970 .sendpage = sock_no_sendpage
1971};
1972
1973static const struct net_proto_family tipc_family_ops = {
1974 .owner = THIS_MODULE,
1975 .family = AF_TIPC,
1976 .create = tipc_sk_create
1977};
1978
1979static struct proto tipc_proto = {
1980 .name = "TIPC",
1981 .owner = THIS_MODULE,
1982 .obj_size = sizeof(struct tipc_sock),
1983 .sysctl_rmem = sysctl_tipc_rmem
1984};
1985
1986static struct proto tipc_proto_kern = {
1987 .name = "TIPC",
1988 .obj_size = sizeof(struct tipc_sock),
1989 .sysctl_rmem = sysctl_tipc_rmem
1990};
1991
1992/**
1993 * tipc_socket_init - initialize TIPC socket interface
1994 *
1995 * Returns 0 on success, errno otherwise
1996 */
1997int tipc_socket_init(void)
1998{
1999 int res;
2000
2001 res = proto_register(&tipc_proto, 1);
2002 if (res) {
2003 pr_err("Failed to register TIPC protocol type\n");
2004 goto out;
2005 }
2006
2007 res = sock_register(&tipc_family_ops);
2008 if (res) {
2009 pr_err("Failed to register TIPC socket type\n");
2010 proto_unregister(&tipc_proto);
2011 goto out;
2012 }
2013 out:
2014 return res;
2015}
2016
2017/**
2018 * tipc_socket_stop - stop TIPC socket interface
2019 */
2020void tipc_socket_stop(void)
2021{
2022 sock_unregister(tipc_family_ops.family);
2023 proto_unregister(&tipc_proto);
2024}
1/*
2 * net/tipc/socket.c: TIPC socket API
3 *
4 * Copyright (c) 2001-2007, Ericsson AB
5 * Copyright (c) 2004-2008, 2010-2011, Wind River Systems
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions are met:
10 *
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the names of the copyright holders nor the names of its
17 * contributors may be used to endorse or promote products derived from
18 * this software without specific prior written permission.
19 *
20 * Alternatively, this software may be distributed under the terms of the
21 * GNU General Public License ("GPL") version 2 as published by the Free
22 * Software Foundation.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
25 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
28 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
32 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
34 * POSSIBILITY OF SUCH DAMAGE.
35 */
36
37#include <net/sock.h>
38
39#include "core.h"
40#include "port.h"
41
42#define SS_LISTENING -1 /* socket is listening */
43#define SS_READY -2 /* socket is connectionless */
44
45#define OVERLOAD_LIMIT_BASE 5000
46#define CONN_TIMEOUT_DEFAULT 8000 /* default connect timeout = 8s */
47
48struct tipc_sock {
49 struct sock sk;
50 struct tipc_port *p;
51 struct tipc_portid peer_name;
52 long conn_timeout;
53};
54
55#define tipc_sk(sk) ((struct tipc_sock *)(sk))
56#define tipc_sk_port(sk) ((struct tipc_port *)(tipc_sk(sk)->p))
57
58#define tipc_rx_ready(sock) (!skb_queue_empty(&sock->sk->sk_receive_queue) || \
59 (sock->state == SS_DISCONNECTING))
60
61static int backlog_rcv(struct sock *sk, struct sk_buff *skb);
62static u32 dispatch(struct tipc_port *tport, struct sk_buff *buf);
63static void wakeupdispatch(struct tipc_port *tport);
64
65static const struct proto_ops packet_ops;
66static const struct proto_ops stream_ops;
67static const struct proto_ops msg_ops;
68
69static struct proto tipc_proto;
70
71static int sockets_enabled;
72
73static atomic_t tipc_queue_size = ATOMIC_INIT(0);
74
75/*
76 * Revised TIPC socket locking policy:
77 *
78 * Most socket operations take the standard socket lock when they start
79 * and hold it until they finish (or until they need to sleep). Acquiring
80 * this lock grants the owner exclusive access to the fields of the socket
81 * data structures, with the exception of the backlog queue. A few socket
82 * operations can be done without taking the socket lock because they only
83 * read socket information that never changes during the life of the socket.
84 *
85 * Socket operations may acquire the lock for the associated TIPC port if they
86 * need to perform an operation on the port. If any routine needs to acquire
87 * both the socket lock and the port lock it must take the socket lock first
88 * to avoid the risk of deadlock.
89 *
90 * The dispatcher handling incoming messages cannot grab the socket lock in
91 * the standard fashion, since invoked it runs at the BH level and cannot block.
92 * Instead, it checks to see if the socket lock is currently owned by someone,
93 * and either handles the message itself or adds it to the socket's backlog
94 * queue; in the latter case the queued message is processed once the process
95 * owning the socket lock releases it.
96 *
97 * NOTE: Releasing the socket lock while an operation is sleeping overcomes
98 * the problem of a blocked socket operation preventing any other operations
99 * from occurring. However, applications must be careful if they have
100 * multiple threads trying to send (or receive) on the same socket, as these
101 * operations might interfere with each other. For example, doing a connect
102 * and a receive at the same time might allow the receive to consume the
103 * ACK message meant for the connect. While additional work could be done
104 * to try and overcome this, it doesn't seem to be worthwhile at the present.
105 *
106 * NOTE: Releasing the socket lock while an operation is sleeping also ensures
107 * that another operation that must be performed in a non-blocking manner is
108 * not delayed for very long because the lock has already been taken.
109 *
110 * NOTE: This code assumes that certain fields of a port/socket pair are
111 * constant over its lifetime; such fields can be examined without taking
112 * the socket lock and/or port lock, and do not need to be re-read even
113 * after resuming processing after waiting. These fields include:
114 * - socket type
115 * - pointer to socket sk structure (aka tipc_sock structure)
116 * - pointer to port structure
117 * - port reference
118 */
119
120/**
121 * advance_rx_queue - discard first buffer in socket receive queue
122 *
123 * Caller must hold socket lock
124 */
125
126static void advance_rx_queue(struct sock *sk)
127{
128 buf_discard(__skb_dequeue(&sk->sk_receive_queue));
129 atomic_dec(&tipc_queue_size);
130}
131
132/**
133 * discard_rx_queue - discard all buffers in socket receive queue
134 *
135 * Caller must hold socket lock
136 */
137
138static void discard_rx_queue(struct sock *sk)
139{
140 struct sk_buff *buf;
141
142 while ((buf = __skb_dequeue(&sk->sk_receive_queue))) {
143 atomic_dec(&tipc_queue_size);
144 buf_discard(buf);
145 }
146}
147
148/**
149 * reject_rx_queue - reject all buffers in socket receive queue
150 *
151 * Caller must hold socket lock
152 */
153
154static void reject_rx_queue(struct sock *sk)
155{
156 struct sk_buff *buf;
157
158 while ((buf = __skb_dequeue(&sk->sk_receive_queue))) {
159 tipc_reject_msg(buf, TIPC_ERR_NO_PORT);
160 atomic_dec(&tipc_queue_size);
161 }
162}
163
164/**
165 * tipc_create - create a TIPC socket
166 * @net: network namespace (must be default network)
167 * @sock: pre-allocated socket structure
168 * @protocol: protocol indicator (must be 0)
169 * @kern: caused by kernel or by userspace?
170 *
171 * This routine creates additional data structures used by the TIPC socket,
172 * initializes them, and links them together.
173 *
174 * Returns 0 on success, errno otherwise
175 */
176
177static int tipc_create(struct net *net, struct socket *sock, int protocol,
178 int kern)
179{
180 const struct proto_ops *ops;
181 socket_state state;
182 struct sock *sk;
183 struct tipc_port *tp_ptr;
184
185 /* Validate arguments */
186
187 if (!net_eq(net, &init_net))
188 return -EAFNOSUPPORT;
189
190 if (unlikely(protocol != 0))
191 return -EPROTONOSUPPORT;
192
193 switch (sock->type) {
194 case SOCK_STREAM:
195 ops = &stream_ops;
196 state = SS_UNCONNECTED;
197 break;
198 case SOCK_SEQPACKET:
199 ops = &packet_ops;
200 state = SS_UNCONNECTED;
201 break;
202 case SOCK_DGRAM:
203 case SOCK_RDM:
204 ops = &msg_ops;
205 state = SS_READY;
206 break;
207 default:
208 return -EPROTOTYPE;
209 }
210
211 /* Allocate socket's protocol area */
212
213 sk = sk_alloc(net, AF_TIPC, GFP_KERNEL, &tipc_proto);
214 if (sk == NULL)
215 return -ENOMEM;
216
217 /* Allocate TIPC port for socket to use */
218
219 tp_ptr = tipc_createport_raw(sk, &dispatch, &wakeupdispatch,
220 TIPC_LOW_IMPORTANCE);
221 if (unlikely(!tp_ptr)) {
222 sk_free(sk);
223 return -ENOMEM;
224 }
225
226 /* Finish initializing socket data structures */
227
228 sock->ops = ops;
229 sock->state = state;
230
231 sock_init_data(sock, sk);
232 sk->sk_backlog_rcv = backlog_rcv;
233 tipc_sk(sk)->p = tp_ptr;
234 tipc_sk(sk)->conn_timeout = msecs_to_jiffies(CONN_TIMEOUT_DEFAULT);
235
236 spin_unlock_bh(tp_ptr->lock);
237
238 if (sock->state == SS_READY) {
239 tipc_set_portunreturnable(tp_ptr->ref, 1);
240 if (sock->type == SOCK_DGRAM)
241 tipc_set_portunreliable(tp_ptr->ref, 1);
242 }
243
244 return 0;
245}
246
247/**
248 * release - destroy a TIPC socket
249 * @sock: socket to destroy
250 *
251 * This routine cleans up any messages that are still queued on the socket.
252 * For DGRAM and RDM socket types, all queued messages are rejected.
253 * For SEQPACKET and STREAM socket types, the first message is rejected
254 * and any others are discarded. (If the first message on a STREAM socket
255 * is partially-read, it is discarded and the next one is rejected instead.)
256 *
257 * NOTE: Rejected messages are not necessarily returned to the sender! They
258 * are returned or discarded according to the "destination droppable" setting
259 * specified for the message by the sender.
260 *
261 * Returns 0 on success, errno otherwise
262 */
263
264static int release(struct socket *sock)
265{
266 struct sock *sk = sock->sk;
267 struct tipc_port *tport;
268 struct sk_buff *buf;
269 int res;
270
271 /*
272 * Exit if socket isn't fully initialized (occurs when a failed accept()
273 * releases a pre-allocated child socket that was never used)
274 */
275
276 if (sk == NULL)
277 return 0;
278
279 tport = tipc_sk_port(sk);
280 lock_sock(sk);
281
282 /*
283 * Reject all unreceived messages, except on an active connection
284 * (which disconnects locally & sends a 'FIN+' to peer)
285 */
286
287 while (sock->state != SS_DISCONNECTING) {
288 buf = __skb_dequeue(&sk->sk_receive_queue);
289 if (buf == NULL)
290 break;
291 atomic_dec(&tipc_queue_size);
292 if (TIPC_SKB_CB(buf)->handle != 0)
293 buf_discard(buf);
294 else {
295 if ((sock->state == SS_CONNECTING) ||
296 (sock->state == SS_CONNECTED)) {
297 sock->state = SS_DISCONNECTING;
298 tipc_disconnect(tport->ref);
299 }
300 tipc_reject_msg(buf, TIPC_ERR_NO_PORT);
301 }
302 }
303
304 /*
305 * Delete TIPC port; this ensures no more messages are queued
306 * (also disconnects an active connection & sends a 'FIN-' to peer)
307 */
308
309 res = tipc_deleteport(tport->ref);
310
311 /* Discard any remaining (connection-based) messages in receive queue */
312
313 discard_rx_queue(sk);
314
315 /* Reject any messages that accumulated in backlog queue */
316
317 sock->state = SS_DISCONNECTING;
318 release_sock(sk);
319
320 sock_put(sk);
321 sock->sk = NULL;
322
323 return res;
324}
325
326/**
327 * bind - associate or disassocate TIPC name(s) with a socket
328 * @sock: socket structure
329 * @uaddr: socket address describing name(s) and desired operation
330 * @uaddr_len: size of socket address data structure
331 *
332 * Name and name sequence binding is indicated using a positive scope value;
333 * a negative scope value unbinds the specified name. Specifying no name
334 * (i.e. a socket address length of 0) unbinds all names from the socket.
335 *
336 * Returns 0 on success, errno otherwise
337 *
338 * NOTE: This routine doesn't need to take the socket lock since it doesn't
339 * access any non-constant socket information.
340 */
341
342static int bind(struct socket *sock, struct sockaddr *uaddr, int uaddr_len)
343{
344 struct sockaddr_tipc *addr = (struct sockaddr_tipc *)uaddr;
345 u32 portref = tipc_sk_port(sock->sk)->ref;
346
347 if (unlikely(!uaddr_len))
348 return tipc_withdraw(portref, 0, NULL);
349
350 if (uaddr_len < sizeof(struct sockaddr_tipc))
351 return -EINVAL;
352 if (addr->family != AF_TIPC)
353 return -EAFNOSUPPORT;
354
355 if (addr->addrtype == TIPC_ADDR_NAME)
356 addr->addr.nameseq.upper = addr->addr.nameseq.lower;
357 else if (addr->addrtype != TIPC_ADDR_NAMESEQ)
358 return -EAFNOSUPPORT;
359
360 return (addr->scope > 0) ?
361 tipc_publish(portref, addr->scope, &addr->addr.nameseq) :
362 tipc_withdraw(portref, -addr->scope, &addr->addr.nameseq);
363}
364
365/**
366 * get_name - get port ID of socket or peer socket
367 * @sock: socket structure
368 * @uaddr: area for returned socket address
369 * @uaddr_len: area for returned length of socket address
370 * @peer: 0 = own ID, 1 = current peer ID, 2 = current/former peer ID
371 *
372 * Returns 0 on success, errno otherwise
373 *
374 * NOTE: This routine doesn't need to take the socket lock since it only
375 * accesses socket information that is unchanging (or which changes in
376 * a completely predictable manner).
377 */
378
379static int get_name(struct socket *sock, struct sockaddr *uaddr,
380 int *uaddr_len, int peer)
381{
382 struct sockaddr_tipc *addr = (struct sockaddr_tipc *)uaddr;
383 struct tipc_sock *tsock = tipc_sk(sock->sk);
384
385 memset(addr, 0, sizeof(*addr));
386 if (peer) {
387 if ((sock->state != SS_CONNECTED) &&
388 ((peer != 2) || (sock->state != SS_DISCONNECTING)))
389 return -ENOTCONN;
390 addr->addr.id.ref = tsock->peer_name.ref;
391 addr->addr.id.node = tsock->peer_name.node;
392 } else {
393 addr->addr.id.ref = tsock->p->ref;
394 addr->addr.id.node = tipc_own_addr;
395 }
396
397 *uaddr_len = sizeof(*addr);
398 addr->addrtype = TIPC_ADDR_ID;
399 addr->family = AF_TIPC;
400 addr->scope = 0;
401 addr->addr.name.domain = 0;
402
403 return 0;
404}
405
406/**
407 * poll - read and possibly block on pollmask
408 * @file: file structure associated with the socket
409 * @sock: socket for which to calculate the poll bits
410 * @wait: ???
411 *
412 * Returns pollmask value
413 *
414 * COMMENTARY:
415 * It appears that the usual socket locking mechanisms are not useful here
416 * since the pollmask info is potentially out-of-date the moment this routine
417 * exits. TCP and other protocols seem to rely on higher level poll routines
418 * to handle any preventable race conditions, so TIPC will do the same ...
419 *
420 * TIPC sets the returned events as follows:
421 *
422 * socket state flags set
423 * ------------ ---------
424 * unconnected no read flags
425 * no write flags
426 *
427 * connecting POLLIN/POLLRDNORM if ACK/NACK in rx queue
428 * no write flags
429 *
430 * connected POLLIN/POLLRDNORM if data in rx queue
431 * POLLOUT if port is not congested
432 *
433 * disconnecting POLLIN/POLLRDNORM/POLLHUP
434 * no write flags
435 *
436 * listening POLLIN if SYN in rx queue
437 * no write flags
438 *
439 * ready POLLIN/POLLRDNORM if data in rx queue
440 * [connectionless] POLLOUT (since port cannot be congested)
441 *
442 * IMPORTANT: The fact that a read or write operation is indicated does NOT
443 * imply that the operation will succeed, merely that it should be performed
444 * and will not block.
445 */
446
447static unsigned int poll(struct file *file, struct socket *sock,
448 poll_table *wait)
449{
450 struct sock *sk = sock->sk;
451 u32 mask = 0;
452
453 poll_wait(file, sk_sleep(sk), wait);
454
455 switch ((int)sock->state) {
456 case SS_READY:
457 case SS_CONNECTED:
458 if (!tipc_sk_port(sk)->congested)
459 mask |= POLLOUT;
460 /* fall thru' */
461 case SS_CONNECTING:
462 case SS_LISTENING:
463 if (!skb_queue_empty(&sk->sk_receive_queue))
464 mask |= (POLLIN | POLLRDNORM);
465 break;
466 case SS_DISCONNECTING:
467 mask = (POLLIN | POLLRDNORM | POLLHUP);
468 break;
469 }
470
471 return mask;
472}
473
474/**
475 * dest_name_check - verify user is permitted to send to specified port name
476 * @dest: destination address
477 * @m: descriptor for message to be sent
478 *
479 * Prevents restricted configuration commands from being issued by
480 * unauthorized users.
481 *
482 * Returns 0 if permission is granted, otherwise errno
483 */
484
485static int dest_name_check(struct sockaddr_tipc *dest, struct msghdr *m)
486{
487 struct tipc_cfg_msg_hdr hdr;
488
489 if (likely(dest->addr.name.name.type >= TIPC_RESERVED_TYPES))
490 return 0;
491 if (likely(dest->addr.name.name.type == TIPC_TOP_SRV))
492 return 0;
493 if (likely(dest->addr.name.name.type != TIPC_CFG_SRV))
494 return -EACCES;
495
496 if (!m->msg_iovlen || (m->msg_iov[0].iov_len < sizeof(hdr)))
497 return -EMSGSIZE;
498 if (copy_from_user(&hdr, m->msg_iov[0].iov_base, sizeof(hdr)))
499 return -EFAULT;
500 if ((ntohs(hdr.tcm_type) & 0xC000) && (!capable(CAP_NET_ADMIN)))
501 return -EACCES;
502
503 return 0;
504}
505
506/**
507 * send_msg - send message in connectionless manner
508 * @iocb: if NULL, indicates that socket lock is already held
509 * @sock: socket structure
510 * @m: message to send
511 * @total_len: length of message
512 *
513 * Message must have an destination specified explicitly.
514 * Used for SOCK_RDM and SOCK_DGRAM messages,
515 * and for 'SYN' messages on SOCK_SEQPACKET and SOCK_STREAM connections.
516 * (Note: 'SYN+' is prohibited on SOCK_STREAM.)
517 *
518 * Returns the number of bytes sent on success, or errno otherwise
519 */
520
521static int send_msg(struct kiocb *iocb, struct socket *sock,
522 struct msghdr *m, size_t total_len)
523{
524 struct sock *sk = sock->sk;
525 struct tipc_port *tport = tipc_sk_port(sk);
526 struct sockaddr_tipc *dest = (struct sockaddr_tipc *)m->msg_name;
527 int needs_conn;
528 int res = -EINVAL;
529
530 if (unlikely(!dest))
531 return -EDESTADDRREQ;
532 if (unlikely((m->msg_namelen < sizeof(*dest)) ||
533 (dest->family != AF_TIPC)))
534 return -EINVAL;
535 if ((total_len > TIPC_MAX_USER_MSG_SIZE) ||
536 (m->msg_iovlen > (unsigned)INT_MAX))
537 return -EMSGSIZE;
538
539 if (iocb)
540 lock_sock(sk);
541
542 needs_conn = (sock->state != SS_READY);
543 if (unlikely(needs_conn)) {
544 if (sock->state == SS_LISTENING) {
545 res = -EPIPE;
546 goto exit;
547 }
548 if (sock->state != SS_UNCONNECTED) {
549 res = -EISCONN;
550 goto exit;
551 }
552 if ((tport->published) ||
553 ((sock->type == SOCK_STREAM) && (total_len != 0))) {
554 res = -EOPNOTSUPP;
555 goto exit;
556 }
557 if (dest->addrtype == TIPC_ADDR_NAME) {
558 tport->conn_type = dest->addr.name.name.type;
559 tport->conn_instance = dest->addr.name.name.instance;
560 }
561
562 /* Abort any pending connection attempts (very unlikely) */
563
564 reject_rx_queue(sk);
565 }
566
567 do {
568 if (dest->addrtype == TIPC_ADDR_NAME) {
569 res = dest_name_check(dest, m);
570 if (res)
571 break;
572 res = tipc_send2name(tport->ref,
573 &dest->addr.name.name,
574 dest->addr.name.domain,
575 m->msg_iovlen,
576 m->msg_iov,
577 total_len);
578 } else if (dest->addrtype == TIPC_ADDR_ID) {
579 res = tipc_send2port(tport->ref,
580 &dest->addr.id,
581 m->msg_iovlen,
582 m->msg_iov,
583 total_len);
584 } else if (dest->addrtype == TIPC_ADDR_MCAST) {
585 if (needs_conn) {
586 res = -EOPNOTSUPP;
587 break;
588 }
589 res = dest_name_check(dest, m);
590 if (res)
591 break;
592 res = tipc_multicast(tport->ref,
593 &dest->addr.nameseq,
594 m->msg_iovlen,
595 m->msg_iov,
596 total_len);
597 }
598 if (likely(res != -ELINKCONG)) {
599 if (needs_conn && (res >= 0))
600 sock->state = SS_CONNECTING;
601 break;
602 }
603 if (m->msg_flags & MSG_DONTWAIT) {
604 res = -EWOULDBLOCK;
605 break;
606 }
607 release_sock(sk);
608 res = wait_event_interruptible(*sk_sleep(sk),
609 !tport->congested);
610 lock_sock(sk);
611 if (res)
612 break;
613 } while (1);
614
615exit:
616 if (iocb)
617 release_sock(sk);
618 return res;
619}
620
621/**
622 * send_packet - send a connection-oriented message
623 * @iocb: if NULL, indicates that socket lock is already held
624 * @sock: socket structure
625 * @m: message to send
626 * @total_len: length of message
627 *
628 * Used for SOCK_SEQPACKET messages and SOCK_STREAM data.
629 *
630 * Returns the number of bytes sent on success, or errno otherwise
631 */
632
633static int send_packet(struct kiocb *iocb, struct socket *sock,
634 struct msghdr *m, size_t total_len)
635{
636 struct sock *sk = sock->sk;
637 struct tipc_port *tport = tipc_sk_port(sk);
638 struct sockaddr_tipc *dest = (struct sockaddr_tipc *)m->msg_name;
639 int res;
640
641 /* Handle implied connection establishment */
642
643 if (unlikely(dest))
644 return send_msg(iocb, sock, m, total_len);
645
646 if ((total_len > TIPC_MAX_USER_MSG_SIZE) ||
647 (m->msg_iovlen > (unsigned)INT_MAX))
648 return -EMSGSIZE;
649
650 if (iocb)
651 lock_sock(sk);
652
653 do {
654 if (unlikely(sock->state != SS_CONNECTED)) {
655 if (sock->state == SS_DISCONNECTING)
656 res = -EPIPE;
657 else
658 res = -ENOTCONN;
659 break;
660 }
661
662 res = tipc_send(tport->ref, m->msg_iovlen, m->msg_iov,
663 total_len);
664 if (likely(res != -ELINKCONG))
665 break;
666 if (m->msg_flags & MSG_DONTWAIT) {
667 res = -EWOULDBLOCK;
668 break;
669 }
670 release_sock(sk);
671 res = wait_event_interruptible(*sk_sleep(sk),
672 (!tport->congested || !tport->connected));
673 lock_sock(sk);
674 if (res)
675 break;
676 } while (1);
677
678 if (iocb)
679 release_sock(sk);
680 return res;
681}
682
683/**
684 * send_stream - send stream-oriented data
685 * @iocb: (unused)
686 * @sock: socket structure
687 * @m: data to send
688 * @total_len: total length of data to be sent
689 *
690 * Used for SOCK_STREAM data.
691 *
692 * Returns the number of bytes sent on success (or partial success),
693 * or errno if no data sent
694 */
695
696static int send_stream(struct kiocb *iocb, struct socket *sock,
697 struct msghdr *m, size_t total_len)
698{
699 struct sock *sk = sock->sk;
700 struct tipc_port *tport = tipc_sk_port(sk);
701 struct msghdr my_msg;
702 struct iovec my_iov;
703 struct iovec *curr_iov;
704 int curr_iovlen;
705 char __user *curr_start;
706 u32 hdr_size;
707 int curr_left;
708 int bytes_to_send;
709 int bytes_sent;
710 int res;
711
712 lock_sock(sk);
713
714 /* Handle special cases where there is no connection */
715
716 if (unlikely(sock->state != SS_CONNECTED)) {
717 if (sock->state == SS_UNCONNECTED) {
718 res = send_packet(NULL, sock, m, total_len);
719 goto exit;
720 } else if (sock->state == SS_DISCONNECTING) {
721 res = -EPIPE;
722 goto exit;
723 } else {
724 res = -ENOTCONN;
725 goto exit;
726 }
727 }
728
729 if (unlikely(m->msg_name)) {
730 res = -EISCONN;
731 goto exit;
732 }
733
734 if ((total_len > (unsigned)INT_MAX) ||
735 (m->msg_iovlen > (unsigned)INT_MAX)) {
736 res = -EMSGSIZE;
737 goto exit;
738 }
739
740 /*
741 * Send each iovec entry using one or more messages
742 *
743 * Note: This algorithm is good for the most likely case
744 * (i.e. one large iovec entry), but could be improved to pass sets
745 * of small iovec entries into send_packet().
746 */
747
748 curr_iov = m->msg_iov;
749 curr_iovlen = m->msg_iovlen;
750 my_msg.msg_iov = &my_iov;
751 my_msg.msg_iovlen = 1;
752 my_msg.msg_flags = m->msg_flags;
753 my_msg.msg_name = NULL;
754 bytes_sent = 0;
755
756 hdr_size = msg_hdr_sz(&tport->phdr);
757
758 while (curr_iovlen--) {
759 curr_start = curr_iov->iov_base;
760 curr_left = curr_iov->iov_len;
761
762 while (curr_left) {
763 bytes_to_send = tport->max_pkt - hdr_size;
764 if (bytes_to_send > TIPC_MAX_USER_MSG_SIZE)
765 bytes_to_send = TIPC_MAX_USER_MSG_SIZE;
766 if (curr_left < bytes_to_send)
767 bytes_to_send = curr_left;
768 my_iov.iov_base = curr_start;
769 my_iov.iov_len = bytes_to_send;
770 res = send_packet(NULL, sock, &my_msg, bytes_to_send);
771 if (res < 0) {
772 if (bytes_sent)
773 res = bytes_sent;
774 goto exit;
775 }
776 curr_left -= bytes_to_send;
777 curr_start += bytes_to_send;
778 bytes_sent += bytes_to_send;
779 }
780
781 curr_iov++;
782 }
783 res = bytes_sent;
784exit:
785 release_sock(sk);
786 return res;
787}
788
789/**
790 * auto_connect - complete connection setup to a remote port
791 * @sock: socket structure
792 * @msg: peer's response message
793 *
794 * Returns 0 on success, errno otherwise
795 */
796
797static int auto_connect(struct socket *sock, struct tipc_msg *msg)
798{
799 struct tipc_sock *tsock = tipc_sk(sock->sk);
800
801 if (msg_errcode(msg)) {
802 sock->state = SS_DISCONNECTING;
803 return -ECONNREFUSED;
804 }
805
806 tsock->peer_name.ref = msg_origport(msg);
807 tsock->peer_name.node = msg_orignode(msg);
808 tipc_connect2port(tsock->p->ref, &tsock->peer_name);
809 tipc_set_portimportance(tsock->p->ref, msg_importance(msg));
810 sock->state = SS_CONNECTED;
811 return 0;
812}
813
814/**
815 * set_orig_addr - capture sender's address for received message
816 * @m: descriptor for message info
817 * @msg: received message header
818 *
819 * Note: Address is not captured if not requested by receiver.
820 */
821
822static void set_orig_addr(struct msghdr *m, struct tipc_msg *msg)
823{
824 struct sockaddr_tipc *addr = (struct sockaddr_tipc *)m->msg_name;
825
826 if (addr) {
827 addr->family = AF_TIPC;
828 addr->addrtype = TIPC_ADDR_ID;
829 addr->addr.id.ref = msg_origport(msg);
830 addr->addr.id.node = msg_orignode(msg);
831 addr->addr.name.domain = 0; /* could leave uninitialized */
832 addr->scope = 0; /* could leave uninitialized */
833 m->msg_namelen = sizeof(struct sockaddr_tipc);
834 }
835}
836
837/**
838 * anc_data_recv - optionally capture ancillary data for received message
839 * @m: descriptor for message info
840 * @msg: received message header
841 * @tport: TIPC port associated with message
842 *
843 * Note: Ancillary data is not captured if not requested by receiver.
844 *
845 * Returns 0 if successful, otherwise errno
846 */
847
848static int anc_data_recv(struct msghdr *m, struct tipc_msg *msg,
849 struct tipc_port *tport)
850{
851 u32 anc_data[3];
852 u32 err;
853 u32 dest_type;
854 int has_name;
855 int res;
856
857 if (likely(m->msg_controllen == 0))
858 return 0;
859
860 /* Optionally capture errored message object(s) */
861
862 err = msg ? msg_errcode(msg) : 0;
863 if (unlikely(err)) {
864 anc_data[0] = err;
865 anc_data[1] = msg_data_sz(msg);
866 res = put_cmsg(m, SOL_TIPC, TIPC_ERRINFO, 8, anc_data);
867 if (res)
868 return res;
869 if (anc_data[1]) {
870 res = put_cmsg(m, SOL_TIPC, TIPC_RETDATA, anc_data[1],
871 msg_data(msg));
872 if (res)
873 return res;
874 }
875 }
876
877 /* Optionally capture message destination object */
878
879 dest_type = msg ? msg_type(msg) : TIPC_DIRECT_MSG;
880 switch (dest_type) {
881 case TIPC_NAMED_MSG:
882 has_name = 1;
883 anc_data[0] = msg_nametype(msg);
884 anc_data[1] = msg_namelower(msg);
885 anc_data[2] = msg_namelower(msg);
886 break;
887 case TIPC_MCAST_MSG:
888 has_name = 1;
889 anc_data[0] = msg_nametype(msg);
890 anc_data[1] = msg_namelower(msg);
891 anc_data[2] = msg_nameupper(msg);
892 break;
893 case TIPC_CONN_MSG:
894 has_name = (tport->conn_type != 0);
895 anc_data[0] = tport->conn_type;
896 anc_data[1] = tport->conn_instance;
897 anc_data[2] = tport->conn_instance;
898 break;
899 default:
900 has_name = 0;
901 }
902 if (has_name) {
903 res = put_cmsg(m, SOL_TIPC, TIPC_DESTNAME, 12, anc_data);
904 if (res)
905 return res;
906 }
907
908 return 0;
909}
910
911/**
912 * recv_msg - receive packet-oriented message
913 * @iocb: (unused)
914 * @m: descriptor for message info
915 * @buf_len: total size of user buffer area
916 * @flags: receive flags
917 *
918 * Used for SOCK_DGRAM, SOCK_RDM, and SOCK_SEQPACKET messages.
919 * If the complete message doesn't fit in user area, truncate it.
920 *
921 * Returns size of returned message data, errno otherwise
922 */
923
924static int recv_msg(struct kiocb *iocb, struct socket *sock,
925 struct msghdr *m, size_t buf_len, int flags)
926{
927 struct sock *sk = sock->sk;
928 struct tipc_port *tport = tipc_sk_port(sk);
929 struct sk_buff *buf;
930 struct tipc_msg *msg;
931 long timeout;
932 unsigned int sz;
933 u32 err;
934 int res;
935
936 /* Catch invalid receive requests */
937
938 if (unlikely(!buf_len))
939 return -EINVAL;
940
941 lock_sock(sk);
942
943 if (unlikely(sock->state == SS_UNCONNECTED)) {
944 res = -ENOTCONN;
945 goto exit;
946 }
947
948 timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
949restart:
950
951 /* Look for a message in receive queue; wait if necessary */
952
953 while (skb_queue_empty(&sk->sk_receive_queue)) {
954 if (sock->state == SS_DISCONNECTING) {
955 res = -ENOTCONN;
956 goto exit;
957 }
958 if (timeout <= 0L) {
959 res = timeout ? timeout : -EWOULDBLOCK;
960 goto exit;
961 }
962 release_sock(sk);
963 timeout = wait_event_interruptible_timeout(*sk_sleep(sk),
964 tipc_rx_ready(sock),
965 timeout);
966 lock_sock(sk);
967 }
968
969 /* Look at first message in receive queue */
970
971 buf = skb_peek(&sk->sk_receive_queue);
972 msg = buf_msg(buf);
973 sz = msg_data_sz(msg);
974 err = msg_errcode(msg);
975
976 /* Complete connection setup for an implied connect */
977
978 if (unlikely(sock->state == SS_CONNECTING)) {
979 res = auto_connect(sock, msg);
980 if (res)
981 goto exit;
982 }
983
984 /* Discard an empty non-errored message & try again */
985
986 if ((!sz) && (!err)) {
987 advance_rx_queue(sk);
988 goto restart;
989 }
990
991 /* Capture sender's address (optional) */
992
993 set_orig_addr(m, msg);
994
995 /* Capture ancillary data (optional) */
996
997 res = anc_data_recv(m, msg, tport);
998 if (res)
999 goto exit;
1000
1001 /* Capture message data (if valid) & compute return value (always) */
1002
1003 if (!err) {
1004 if (unlikely(buf_len < sz)) {
1005 sz = buf_len;
1006 m->msg_flags |= MSG_TRUNC;
1007 }
1008 res = skb_copy_datagram_iovec(buf, msg_hdr_sz(msg),
1009 m->msg_iov, sz);
1010 if (res)
1011 goto exit;
1012 res = sz;
1013 } else {
1014 if ((sock->state == SS_READY) ||
1015 ((err == TIPC_CONN_SHUTDOWN) || m->msg_control))
1016 res = 0;
1017 else
1018 res = -ECONNRESET;
1019 }
1020
1021 /* Consume received message (optional) */
1022
1023 if (likely(!(flags & MSG_PEEK))) {
1024 if ((sock->state != SS_READY) &&
1025 (++tport->conn_unacked >= TIPC_FLOW_CONTROL_WIN))
1026 tipc_acknowledge(tport->ref, tport->conn_unacked);
1027 advance_rx_queue(sk);
1028 }
1029exit:
1030 release_sock(sk);
1031 return res;
1032}
1033
1034/**
1035 * recv_stream - receive stream-oriented data
1036 * @iocb: (unused)
1037 * @m: descriptor for message info
1038 * @buf_len: total size of user buffer area
1039 * @flags: receive flags
1040 *
1041 * Used for SOCK_STREAM messages only. If not enough data is available
1042 * will optionally wait for more; never truncates data.
1043 *
1044 * Returns size of returned message data, errno otherwise
1045 */
1046
1047static int recv_stream(struct kiocb *iocb, struct socket *sock,
1048 struct msghdr *m, size_t buf_len, int flags)
1049{
1050 struct sock *sk = sock->sk;
1051 struct tipc_port *tport = tipc_sk_port(sk);
1052 struct sk_buff *buf;
1053 struct tipc_msg *msg;
1054 long timeout;
1055 unsigned int sz;
1056 int sz_to_copy, target, needed;
1057 int sz_copied = 0;
1058 u32 err;
1059 int res = 0;
1060
1061 /* Catch invalid receive attempts */
1062
1063 if (unlikely(!buf_len))
1064 return -EINVAL;
1065
1066 lock_sock(sk);
1067
1068 if (unlikely((sock->state == SS_UNCONNECTED) ||
1069 (sock->state == SS_CONNECTING))) {
1070 res = -ENOTCONN;
1071 goto exit;
1072 }
1073
1074 target = sock_rcvlowat(sk, flags & MSG_WAITALL, buf_len);
1075 timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
1076restart:
1077
1078 /* Look for a message in receive queue; wait if necessary */
1079
1080 while (skb_queue_empty(&sk->sk_receive_queue)) {
1081 if (sock->state == SS_DISCONNECTING) {
1082 res = -ENOTCONN;
1083 goto exit;
1084 }
1085 if (timeout <= 0L) {
1086 res = timeout ? timeout : -EWOULDBLOCK;
1087 goto exit;
1088 }
1089 release_sock(sk);
1090 timeout = wait_event_interruptible_timeout(*sk_sleep(sk),
1091 tipc_rx_ready(sock),
1092 timeout);
1093 lock_sock(sk);
1094 }
1095
1096 /* Look at first message in receive queue */
1097
1098 buf = skb_peek(&sk->sk_receive_queue);
1099 msg = buf_msg(buf);
1100 sz = msg_data_sz(msg);
1101 err = msg_errcode(msg);
1102
1103 /* Discard an empty non-errored message & try again */
1104
1105 if ((!sz) && (!err)) {
1106 advance_rx_queue(sk);
1107 goto restart;
1108 }
1109
1110 /* Optionally capture sender's address & ancillary data of first msg */
1111
1112 if (sz_copied == 0) {
1113 set_orig_addr(m, msg);
1114 res = anc_data_recv(m, msg, tport);
1115 if (res)
1116 goto exit;
1117 }
1118
1119 /* Capture message data (if valid) & compute return value (always) */
1120
1121 if (!err) {
1122 u32 offset = (u32)(unsigned long)(TIPC_SKB_CB(buf)->handle);
1123
1124 sz -= offset;
1125 needed = (buf_len - sz_copied);
1126 sz_to_copy = (sz <= needed) ? sz : needed;
1127
1128 res = skb_copy_datagram_iovec(buf, msg_hdr_sz(msg) + offset,
1129 m->msg_iov, sz_to_copy);
1130 if (res)
1131 goto exit;
1132
1133 sz_copied += sz_to_copy;
1134
1135 if (sz_to_copy < sz) {
1136 if (!(flags & MSG_PEEK))
1137 TIPC_SKB_CB(buf)->handle =
1138 (void *)(unsigned long)(offset + sz_to_copy);
1139 goto exit;
1140 }
1141 } else {
1142 if (sz_copied != 0)
1143 goto exit; /* can't add error msg to valid data */
1144
1145 if ((err == TIPC_CONN_SHUTDOWN) || m->msg_control)
1146 res = 0;
1147 else
1148 res = -ECONNRESET;
1149 }
1150
1151 /* Consume received message (optional) */
1152
1153 if (likely(!(flags & MSG_PEEK))) {
1154 if (unlikely(++tport->conn_unacked >= TIPC_FLOW_CONTROL_WIN))
1155 tipc_acknowledge(tport->ref, tport->conn_unacked);
1156 advance_rx_queue(sk);
1157 }
1158
1159 /* Loop around if more data is required */
1160
1161 if ((sz_copied < buf_len) && /* didn't get all requested data */
1162 (!skb_queue_empty(&sk->sk_receive_queue) ||
1163 (sz_copied < target)) && /* and more is ready or required */
1164 (!(flags & MSG_PEEK)) && /* and aren't just peeking at data */
1165 (!err)) /* and haven't reached a FIN */
1166 goto restart;
1167
1168exit:
1169 release_sock(sk);
1170 return sz_copied ? sz_copied : res;
1171}
1172
1173/**
1174 * rx_queue_full - determine if receive queue can accept another message
1175 * @msg: message to be added to queue
1176 * @queue_size: current size of queue
1177 * @base: nominal maximum size of queue
1178 *
1179 * Returns 1 if queue is unable to accept message, 0 otherwise
1180 */
1181
1182static int rx_queue_full(struct tipc_msg *msg, u32 queue_size, u32 base)
1183{
1184 u32 threshold;
1185 u32 imp = msg_importance(msg);
1186
1187 if (imp == TIPC_LOW_IMPORTANCE)
1188 threshold = base;
1189 else if (imp == TIPC_MEDIUM_IMPORTANCE)
1190 threshold = base * 2;
1191 else if (imp == TIPC_HIGH_IMPORTANCE)
1192 threshold = base * 100;
1193 else
1194 return 0;
1195
1196 if (msg_connected(msg))
1197 threshold *= 4;
1198
1199 return queue_size >= threshold;
1200}
1201
1202/**
1203 * filter_rcv - validate incoming message
1204 * @sk: socket
1205 * @buf: message
1206 *
1207 * Enqueues message on receive queue if acceptable; optionally handles
1208 * disconnect indication for a connected socket.
1209 *
1210 * Called with socket lock already taken; port lock may also be taken.
1211 *
1212 * Returns TIPC error status code (TIPC_OK if message is not to be rejected)
1213 */
1214
1215static u32 filter_rcv(struct sock *sk, struct sk_buff *buf)
1216{
1217 struct socket *sock = sk->sk_socket;
1218 struct tipc_msg *msg = buf_msg(buf);
1219 u32 recv_q_len;
1220
1221 /* Reject message if it is wrong sort of message for socket */
1222
1223 /*
1224 * WOULD IT BE BETTER TO JUST DISCARD THESE MESSAGES INSTEAD?
1225 * "NO PORT" ISN'T REALLY THE RIGHT ERROR CODE, AND THERE MAY
1226 * BE SECURITY IMPLICATIONS INHERENT IN REJECTING INVALID TRAFFIC
1227 */
1228
1229 if (sock->state == SS_READY) {
1230 if (msg_connected(msg))
1231 return TIPC_ERR_NO_PORT;
1232 } else {
1233 if (msg_mcast(msg))
1234 return TIPC_ERR_NO_PORT;
1235 if (sock->state == SS_CONNECTED) {
1236 if (!msg_connected(msg))
1237 return TIPC_ERR_NO_PORT;
1238 } else if (sock->state == SS_CONNECTING) {
1239 if (!msg_connected(msg) && (msg_errcode(msg) == 0))
1240 return TIPC_ERR_NO_PORT;
1241 } else if (sock->state == SS_LISTENING) {
1242 if (msg_connected(msg) || msg_errcode(msg))
1243 return TIPC_ERR_NO_PORT;
1244 } else if (sock->state == SS_DISCONNECTING) {
1245 return TIPC_ERR_NO_PORT;
1246 } else /* (sock->state == SS_UNCONNECTED) */ {
1247 if (msg_connected(msg) || msg_errcode(msg))
1248 return TIPC_ERR_NO_PORT;
1249 }
1250 }
1251
1252 /* Reject message if there isn't room to queue it */
1253
1254 recv_q_len = (u32)atomic_read(&tipc_queue_size);
1255 if (unlikely(recv_q_len >= OVERLOAD_LIMIT_BASE)) {
1256 if (rx_queue_full(msg, recv_q_len, OVERLOAD_LIMIT_BASE))
1257 return TIPC_ERR_OVERLOAD;
1258 }
1259 recv_q_len = skb_queue_len(&sk->sk_receive_queue);
1260 if (unlikely(recv_q_len >= (OVERLOAD_LIMIT_BASE / 2))) {
1261 if (rx_queue_full(msg, recv_q_len, OVERLOAD_LIMIT_BASE / 2))
1262 return TIPC_ERR_OVERLOAD;
1263 }
1264
1265 /* Enqueue message (finally!) */
1266
1267 TIPC_SKB_CB(buf)->handle = 0;
1268 atomic_inc(&tipc_queue_size);
1269 __skb_queue_tail(&sk->sk_receive_queue, buf);
1270
1271 /* Initiate connection termination for an incoming 'FIN' */
1272
1273 if (unlikely(msg_errcode(msg) && (sock->state == SS_CONNECTED))) {
1274 sock->state = SS_DISCONNECTING;
1275 tipc_disconnect_port(tipc_sk_port(sk));
1276 }
1277
1278 if (waitqueue_active(sk_sleep(sk)))
1279 wake_up_interruptible(sk_sleep(sk));
1280 return TIPC_OK;
1281}
1282
1283/**
1284 * backlog_rcv - handle incoming message from backlog queue
1285 * @sk: socket
1286 * @buf: message
1287 *
1288 * Caller must hold socket lock, but not port lock.
1289 *
1290 * Returns 0
1291 */
1292
1293static int backlog_rcv(struct sock *sk, struct sk_buff *buf)
1294{
1295 u32 res;
1296
1297 res = filter_rcv(sk, buf);
1298 if (res)
1299 tipc_reject_msg(buf, res);
1300 return 0;
1301}
1302
1303/**
1304 * dispatch - handle incoming message
1305 * @tport: TIPC port that received message
1306 * @buf: message
1307 *
1308 * Called with port lock already taken.
1309 *
1310 * Returns TIPC error status code (TIPC_OK if message is not to be rejected)
1311 */
1312
1313static u32 dispatch(struct tipc_port *tport, struct sk_buff *buf)
1314{
1315 struct sock *sk = (struct sock *)tport->usr_handle;
1316 u32 res;
1317
1318 /*
1319 * Process message if socket is unlocked; otherwise add to backlog queue
1320 *
1321 * This code is based on sk_receive_skb(), but must be distinct from it
1322 * since a TIPC-specific filter/reject mechanism is utilized
1323 */
1324
1325 bh_lock_sock(sk);
1326 if (!sock_owned_by_user(sk)) {
1327 res = filter_rcv(sk, buf);
1328 } else {
1329 if (sk_add_backlog(sk, buf))
1330 res = TIPC_ERR_OVERLOAD;
1331 else
1332 res = TIPC_OK;
1333 }
1334 bh_unlock_sock(sk);
1335
1336 return res;
1337}
1338
1339/**
1340 * wakeupdispatch - wake up port after congestion
1341 * @tport: port to wakeup
1342 *
1343 * Called with port lock already taken.
1344 */
1345
1346static void wakeupdispatch(struct tipc_port *tport)
1347{
1348 struct sock *sk = (struct sock *)tport->usr_handle;
1349
1350 if (waitqueue_active(sk_sleep(sk)))
1351 wake_up_interruptible(sk_sleep(sk));
1352}
1353
1354/**
1355 * connect - establish a connection to another TIPC port
1356 * @sock: socket structure
1357 * @dest: socket address for destination port
1358 * @destlen: size of socket address data structure
1359 * @flags: file-related flags associated with socket
1360 *
1361 * Returns 0 on success, errno otherwise
1362 */
1363
1364static int connect(struct socket *sock, struct sockaddr *dest, int destlen,
1365 int flags)
1366{
1367 struct sock *sk = sock->sk;
1368 struct sockaddr_tipc *dst = (struct sockaddr_tipc *)dest;
1369 struct msghdr m = {NULL,};
1370 struct sk_buff *buf;
1371 struct tipc_msg *msg;
1372 long timeout;
1373 int res;
1374
1375 lock_sock(sk);
1376
1377 /* For now, TIPC does not allow use of connect() with DGRAM/RDM types */
1378
1379 if (sock->state == SS_READY) {
1380 res = -EOPNOTSUPP;
1381 goto exit;
1382 }
1383
1384 /* For now, TIPC does not support the non-blocking form of connect() */
1385
1386 if (flags & O_NONBLOCK) {
1387 res = -EOPNOTSUPP;
1388 goto exit;
1389 }
1390
1391 /* Issue Posix-compliant error code if socket is in the wrong state */
1392
1393 if (sock->state == SS_LISTENING) {
1394 res = -EOPNOTSUPP;
1395 goto exit;
1396 }
1397 if (sock->state == SS_CONNECTING) {
1398 res = -EALREADY;
1399 goto exit;
1400 }
1401 if (sock->state != SS_UNCONNECTED) {
1402 res = -EISCONN;
1403 goto exit;
1404 }
1405
1406 /*
1407 * Reject connection attempt using multicast address
1408 *
1409 * Note: send_msg() validates the rest of the address fields,
1410 * so there's no need to do it here
1411 */
1412
1413 if (dst->addrtype == TIPC_ADDR_MCAST) {
1414 res = -EINVAL;
1415 goto exit;
1416 }
1417
1418 /* Reject any messages already in receive queue (very unlikely) */
1419
1420 reject_rx_queue(sk);
1421
1422 /* Send a 'SYN-' to destination */
1423
1424 m.msg_name = dest;
1425 m.msg_namelen = destlen;
1426 res = send_msg(NULL, sock, &m, 0);
1427 if (res < 0)
1428 goto exit;
1429
1430 /* Wait until an 'ACK' or 'RST' arrives, or a timeout occurs */
1431
1432 timeout = tipc_sk(sk)->conn_timeout;
1433 release_sock(sk);
1434 res = wait_event_interruptible_timeout(*sk_sleep(sk),
1435 (!skb_queue_empty(&sk->sk_receive_queue) ||
1436 (sock->state != SS_CONNECTING)),
1437 timeout ? timeout : MAX_SCHEDULE_TIMEOUT);
1438 lock_sock(sk);
1439
1440 if (res > 0) {
1441 buf = skb_peek(&sk->sk_receive_queue);
1442 if (buf != NULL) {
1443 msg = buf_msg(buf);
1444 res = auto_connect(sock, msg);
1445 if (!res) {
1446 if (!msg_data_sz(msg))
1447 advance_rx_queue(sk);
1448 }
1449 } else {
1450 if (sock->state == SS_CONNECTED)
1451 res = -EISCONN;
1452 else
1453 res = -ECONNREFUSED;
1454 }
1455 } else {
1456 if (res == 0)
1457 res = -ETIMEDOUT;
1458 else
1459 ; /* leave "res" unchanged */
1460 sock->state = SS_DISCONNECTING;
1461 }
1462
1463exit:
1464 release_sock(sk);
1465 return res;
1466}
1467
1468/**
1469 * listen - allow socket to listen for incoming connections
1470 * @sock: socket structure
1471 * @len: (unused)
1472 *
1473 * Returns 0 on success, errno otherwise
1474 */
1475
1476static int listen(struct socket *sock, int len)
1477{
1478 struct sock *sk = sock->sk;
1479 int res;
1480
1481 lock_sock(sk);
1482
1483 if (sock->state == SS_READY)
1484 res = -EOPNOTSUPP;
1485 else if (sock->state != SS_UNCONNECTED)
1486 res = -EINVAL;
1487 else {
1488 sock->state = SS_LISTENING;
1489 res = 0;
1490 }
1491
1492 release_sock(sk);
1493 return res;
1494}
1495
1496/**
1497 * accept - wait for connection request
1498 * @sock: listening socket
1499 * @newsock: new socket that is to be connected
1500 * @flags: file-related flags associated with socket
1501 *
1502 * Returns 0 on success, errno otherwise
1503 */
1504
1505static int accept(struct socket *sock, struct socket *new_sock, int flags)
1506{
1507 struct sock *sk = sock->sk;
1508 struct sk_buff *buf;
1509 int res;
1510
1511 lock_sock(sk);
1512
1513 if (sock->state == SS_READY) {
1514 res = -EOPNOTSUPP;
1515 goto exit;
1516 }
1517 if (sock->state != SS_LISTENING) {
1518 res = -EINVAL;
1519 goto exit;
1520 }
1521
1522 while (skb_queue_empty(&sk->sk_receive_queue)) {
1523 if (flags & O_NONBLOCK) {
1524 res = -EWOULDBLOCK;
1525 goto exit;
1526 }
1527 release_sock(sk);
1528 res = wait_event_interruptible(*sk_sleep(sk),
1529 (!skb_queue_empty(&sk->sk_receive_queue)));
1530 lock_sock(sk);
1531 if (res)
1532 goto exit;
1533 }
1534
1535 buf = skb_peek(&sk->sk_receive_queue);
1536
1537 res = tipc_create(sock_net(sock->sk), new_sock, 0, 0);
1538 if (!res) {
1539 struct sock *new_sk = new_sock->sk;
1540 struct tipc_sock *new_tsock = tipc_sk(new_sk);
1541 struct tipc_port *new_tport = new_tsock->p;
1542 u32 new_ref = new_tport->ref;
1543 struct tipc_msg *msg = buf_msg(buf);
1544
1545 lock_sock(new_sk);
1546
1547 /*
1548 * Reject any stray messages received by new socket
1549 * before the socket lock was taken (very, very unlikely)
1550 */
1551
1552 reject_rx_queue(new_sk);
1553
1554 /* Connect new socket to it's peer */
1555
1556 new_tsock->peer_name.ref = msg_origport(msg);
1557 new_tsock->peer_name.node = msg_orignode(msg);
1558 tipc_connect2port(new_ref, &new_tsock->peer_name);
1559 new_sock->state = SS_CONNECTED;
1560
1561 tipc_set_portimportance(new_ref, msg_importance(msg));
1562 if (msg_named(msg)) {
1563 new_tport->conn_type = msg_nametype(msg);
1564 new_tport->conn_instance = msg_nameinst(msg);
1565 }
1566
1567 /*
1568 * Respond to 'SYN-' by discarding it & returning 'ACK'-.
1569 * Respond to 'SYN+' by queuing it on new socket.
1570 */
1571
1572 if (!msg_data_sz(msg)) {
1573 struct msghdr m = {NULL,};
1574
1575 advance_rx_queue(sk);
1576 send_packet(NULL, new_sock, &m, 0);
1577 } else {
1578 __skb_dequeue(&sk->sk_receive_queue);
1579 __skb_queue_head(&new_sk->sk_receive_queue, buf);
1580 }
1581 release_sock(new_sk);
1582 }
1583exit:
1584 release_sock(sk);
1585 return res;
1586}
1587
1588/**
1589 * shutdown - shutdown socket connection
1590 * @sock: socket structure
1591 * @how: direction to close (must be SHUT_RDWR)
1592 *
1593 * Terminates connection (if necessary), then purges socket's receive queue.
1594 *
1595 * Returns 0 on success, errno otherwise
1596 */
1597
1598static int shutdown(struct socket *sock, int how)
1599{
1600 struct sock *sk = sock->sk;
1601 struct tipc_port *tport = tipc_sk_port(sk);
1602 struct sk_buff *buf;
1603 int res;
1604
1605 if (how != SHUT_RDWR)
1606 return -EINVAL;
1607
1608 lock_sock(sk);
1609
1610 switch (sock->state) {
1611 case SS_CONNECTING:
1612 case SS_CONNECTED:
1613
1614 /* Disconnect and send a 'FIN+' or 'FIN-' message to peer */
1615restart:
1616 buf = __skb_dequeue(&sk->sk_receive_queue);
1617 if (buf) {
1618 atomic_dec(&tipc_queue_size);
1619 if (TIPC_SKB_CB(buf)->handle != 0) {
1620 buf_discard(buf);
1621 goto restart;
1622 }
1623 tipc_disconnect(tport->ref);
1624 tipc_reject_msg(buf, TIPC_CONN_SHUTDOWN);
1625 } else {
1626 tipc_shutdown(tport->ref);
1627 }
1628
1629 sock->state = SS_DISCONNECTING;
1630
1631 /* fall through */
1632
1633 case SS_DISCONNECTING:
1634
1635 /* Discard any unreceived messages; wake up sleeping tasks */
1636
1637 discard_rx_queue(sk);
1638 if (waitqueue_active(sk_sleep(sk)))
1639 wake_up_interruptible(sk_sleep(sk));
1640 res = 0;
1641 break;
1642
1643 default:
1644 res = -ENOTCONN;
1645 }
1646
1647 release_sock(sk);
1648 return res;
1649}
1650
1651/**
1652 * setsockopt - set socket option
1653 * @sock: socket structure
1654 * @lvl: option level
1655 * @opt: option identifier
1656 * @ov: pointer to new option value
1657 * @ol: length of option value
1658 *
1659 * For stream sockets only, accepts and ignores all IPPROTO_TCP options
1660 * (to ease compatibility).
1661 *
1662 * Returns 0 on success, errno otherwise
1663 */
1664
1665static int setsockopt(struct socket *sock,
1666 int lvl, int opt, char __user *ov, unsigned int ol)
1667{
1668 struct sock *sk = sock->sk;
1669 struct tipc_port *tport = tipc_sk_port(sk);
1670 u32 value;
1671 int res;
1672
1673 if ((lvl == IPPROTO_TCP) && (sock->type == SOCK_STREAM))
1674 return 0;
1675 if (lvl != SOL_TIPC)
1676 return -ENOPROTOOPT;
1677 if (ol < sizeof(value))
1678 return -EINVAL;
1679 res = get_user(value, (u32 __user *)ov);
1680 if (res)
1681 return res;
1682
1683 lock_sock(sk);
1684
1685 switch (opt) {
1686 case TIPC_IMPORTANCE:
1687 res = tipc_set_portimportance(tport->ref, value);
1688 break;
1689 case TIPC_SRC_DROPPABLE:
1690 if (sock->type != SOCK_STREAM)
1691 res = tipc_set_portunreliable(tport->ref, value);
1692 else
1693 res = -ENOPROTOOPT;
1694 break;
1695 case TIPC_DEST_DROPPABLE:
1696 res = tipc_set_portunreturnable(tport->ref, value);
1697 break;
1698 case TIPC_CONN_TIMEOUT:
1699 tipc_sk(sk)->conn_timeout = msecs_to_jiffies(value);
1700 /* no need to set "res", since already 0 at this point */
1701 break;
1702 default:
1703 res = -EINVAL;
1704 }
1705
1706 release_sock(sk);
1707
1708 return res;
1709}
1710
1711/**
1712 * getsockopt - get socket option
1713 * @sock: socket structure
1714 * @lvl: option level
1715 * @opt: option identifier
1716 * @ov: receptacle for option value
1717 * @ol: receptacle for length of option value
1718 *
1719 * For stream sockets only, returns 0 length result for all IPPROTO_TCP options
1720 * (to ease compatibility).
1721 *
1722 * Returns 0 on success, errno otherwise
1723 */
1724
1725static int getsockopt(struct socket *sock,
1726 int lvl, int opt, char __user *ov, int __user *ol)
1727{
1728 struct sock *sk = sock->sk;
1729 struct tipc_port *tport = tipc_sk_port(sk);
1730 int len;
1731 u32 value;
1732 int res;
1733
1734 if ((lvl == IPPROTO_TCP) && (sock->type == SOCK_STREAM))
1735 return put_user(0, ol);
1736 if (lvl != SOL_TIPC)
1737 return -ENOPROTOOPT;
1738 res = get_user(len, ol);
1739 if (res)
1740 return res;
1741
1742 lock_sock(sk);
1743
1744 switch (opt) {
1745 case TIPC_IMPORTANCE:
1746 res = tipc_portimportance(tport->ref, &value);
1747 break;
1748 case TIPC_SRC_DROPPABLE:
1749 res = tipc_portunreliable(tport->ref, &value);
1750 break;
1751 case TIPC_DEST_DROPPABLE:
1752 res = tipc_portunreturnable(tport->ref, &value);
1753 break;
1754 case TIPC_CONN_TIMEOUT:
1755 value = jiffies_to_msecs(tipc_sk(sk)->conn_timeout);
1756 /* no need to set "res", since already 0 at this point */
1757 break;
1758 case TIPC_NODE_RECVQ_DEPTH:
1759 value = (u32)atomic_read(&tipc_queue_size);
1760 break;
1761 case TIPC_SOCK_RECVQ_DEPTH:
1762 value = skb_queue_len(&sk->sk_receive_queue);
1763 break;
1764 default:
1765 res = -EINVAL;
1766 }
1767
1768 release_sock(sk);
1769
1770 if (res)
1771 return res; /* "get" failed */
1772
1773 if (len < sizeof(value))
1774 return -EINVAL;
1775
1776 if (copy_to_user(ov, &value, sizeof(value)))
1777 return -EFAULT;
1778
1779 return put_user(sizeof(value), ol);
1780}
1781
1782/**
1783 * Protocol switches for the various types of TIPC sockets
1784 */
1785
1786static const struct proto_ops msg_ops = {
1787 .owner = THIS_MODULE,
1788 .family = AF_TIPC,
1789 .release = release,
1790 .bind = bind,
1791 .connect = connect,
1792 .socketpair = sock_no_socketpair,
1793 .accept = accept,
1794 .getname = get_name,
1795 .poll = poll,
1796 .ioctl = sock_no_ioctl,
1797 .listen = listen,
1798 .shutdown = shutdown,
1799 .setsockopt = setsockopt,
1800 .getsockopt = getsockopt,
1801 .sendmsg = send_msg,
1802 .recvmsg = recv_msg,
1803 .mmap = sock_no_mmap,
1804 .sendpage = sock_no_sendpage
1805};
1806
1807static const struct proto_ops packet_ops = {
1808 .owner = THIS_MODULE,
1809 .family = AF_TIPC,
1810 .release = release,
1811 .bind = bind,
1812 .connect = connect,
1813 .socketpair = sock_no_socketpair,
1814 .accept = accept,
1815 .getname = get_name,
1816 .poll = poll,
1817 .ioctl = sock_no_ioctl,
1818 .listen = listen,
1819 .shutdown = shutdown,
1820 .setsockopt = setsockopt,
1821 .getsockopt = getsockopt,
1822 .sendmsg = send_packet,
1823 .recvmsg = recv_msg,
1824 .mmap = sock_no_mmap,
1825 .sendpage = sock_no_sendpage
1826};
1827
1828static const struct proto_ops stream_ops = {
1829 .owner = THIS_MODULE,
1830 .family = AF_TIPC,
1831 .release = release,
1832 .bind = bind,
1833 .connect = connect,
1834 .socketpair = sock_no_socketpair,
1835 .accept = accept,
1836 .getname = get_name,
1837 .poll = poll,
1838 .ioctl = sock_no_ioctl,
1839 .listen = listen,
1840 .shutdown = shutdown,
1841 .setsockopt = setsockopt,
1842 .getsockopt = getsockopt,
1843 .sendmsg = send_stream,
1844 .recvmsg = recv_stream,
1845 .mmap = sock_no_mmap,
1846 .sendpage = sock_no_sendpage
1847};
1848
1849static const struct net_proto_family tipc_family_ops = {
1850 .owner = THIS_MODULE,
1851 .family = AF_TIPC,
1852 .create = tipc_create
1853};
1854
1855static struct proto tipc_proto = {
1856 .name = "TIPC",
1857 .owner = THIS_MODULE,
1858 .obj_size = sizeof(struct tipc_sock)
1859};
1860
1861/**
1862 * tipc_socket_init - initialize TIPC socket interface
1863 *
1864 * Returns 0 on success, errno otherwise
1865 */
1866int tipc_socket_init(void)
1867{
1868 int res;
1869
1870 res = proto_register(&tipc_proto, 1);
1871 if (res) {
1872 err("Failed to register TIPC protocol type\n");
1873 goto out;
1874 }
1875
1876 res = sock_register(&tipc_family_ops);
1877 if (res) {
1878 err("Failed to register TIPC socket type\n");
1879 proto_unregister(&tipc_proto);
1880 goto out;
1881 }
1882
1883 sockets_enabled = 1;
1884 out:
1885 return res;
1886}
1887
1888/**
1889 * tipc_socket_stop - stop TIPC socket interface
1890 */
1891
1892void tipc_socket_stop(void)
1893{
1894 if (!sockets_enabled)
1895 return;
1896
1897 sockets_enabled = 0;
1898 sock_unregister(tipc_family_ops.family);
1899 proto_unregister(&tipc_proto);
1900}
1901