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