xref: /linux/net/tipc/socket.c (revision f3539c12d8196ce0a1993364d30b3a18908470d1)
1 /*
2  * net/tipc/socket.c: TIPC socket API
3  *
4  * Copyright (c) 2001-2007, 2012-2015, 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 <linux/rhashtable.h>
38 #include "core.h"
39 #include "name_table.h"
40 #include "node.h"
41 #include "link.h"
42 #include "name_distr.h"
43 #include "socket.h"
44 #include "bcast.h"
45 #include "netlink.h"
46 
47 #define SS_LISTENING		-1	/* socket is listening */
48 #define SS_READY		-2	/* socket is connectionless */
49 
50 #define CONN_TIMEOUT_DEFAULT	8000	/* default connect timeout = 8s */
51 #define CONN_PROBING_INTERVAL	msecs_to_jiffies(3600000)  /* [ms] => 1 h */
52 #define TIPC_FWD_MSG		1
53 #define TIPC_CONN_OK		0
54 #define TIPC_CONN_PROBING	1
55 #define TIPC_MAX_PORT		0xffffffff
56 #define TIPC_MIN_PORT		1
57 
58 /**
59  * struct tipc_sock - TIPC socket structure
60  * @sk: socket - interacts with 'port' and with user via the socket API
61  * @connected: non-zero if port is currently connected to a peer port
62  * @conn_type: TIPC type used when connection was established
63  * @conn_instance: TIPC instance used when connection was established
64  * @published: non-zero if port has one or more associated names
65  * @max_pkt: maximum packet size "hint" used when building messages sent by port
66  * @portid: unique port identity in TIPC socket hash table
67  * @phdr: preformatted message header used when sending messages
68  * @port_list: adjacent ports in TIPC's global list of ports
69  * @publications: list of publications for port
70  * @pub_count: total # of publications port has made during its lifetime
71  * @probing_state:
72  * @probing_intv:
73  * @conn_timeout: the time we can wait for an unresponded setup request
74  * @dupl_rcvcnt: number of bytes counted twice, in both backlog and rcv queue
75  * @link_cong: non-zero if owner must sleep because of link congestion
76  * @sent_unacked: # messages sent by socket, and not yet acked by peer
77  * @rcv_unacked: # messages read by user, but not yet acked back to peer
78  * @remote: 'connected' peer for dgram/rdm
79  * @node: hash table node
80  * @rcu: rcu struct for tipc_sock
81  */
82 struct tipc_sock {
83 	struct sock sk;
84 	int connected;
85 	u32 conn_type;
86 	u32 conn_instance;
87 	int published;
88 	u32 max_pkt;
89 	u32 portid;
90 	struct tipc_msg phdr;
91 	struct list_head sock_list;
92 	struct list_head publications;
93 	u32 pub_count;
94 	u32 probing_state;
95 	unsigned long probing_intv;
96 	uint conn_timeout;
97 	atomic_t dupl_rcvcnt;
98 	bool link_cong;
99 	u16 snt_unacked;
100 	u16 snd_win;
101 	u16 peer_caps;
102 	u16 rcv_unacked;
103 	u16 rcv_win;
104 	struct sockaddr_tipc remote;
105 	struct rhash_head node;
106 	struct rcu_head rcu;
107 };
108 
109 static int tipc_backlog_rcv(struct sock *sk, struct sk_buff *skb);
110 static void tipc_data_ready(struct sock *sk);
111 static void tipc_write_space(struct sock *sk);
112 static void tipc_sock_destruct(struct sock *sk);
113 static int tipc_release(struct socket *sock);
114 static int tipc_accept(struct socket *sock, struct socket *new_sock, int flags);
115 static int tipc_wait_for_sndmsg(struct socket *sock, long *timeo_p);
116 static void tipc_sk_timeout(unsigned long data);
117 static int tipc_sk_publish(struct tipc_sock *tsk, uint scope,
118 			   struct tipc_name_seq const *seq);
119 static int tipc_sk_withdraw(struct tipc_sock *tsk, uint scope,
120 			    struct tipc_name_seq const *seq);
121 static struct tipc_sock *tipc_sk_lookup(struct net *net, u32 portid);
122 static int tipc_sk_insert(struct tipc_sock *tsk);
123 static void tipc_sk_remove(struct tipc_sock *tsk);
124 static int __tipc_send_stream(struct socket *sock, struct msghdr *m,
125 			      size_t dsz);
126 static int __tipc_sendmsg(struct socket *sock, struct msghdr *m, size_t dsz);
127 
128 static const struct proto_ops packet_ops;
129 static const struct proto_ops stream_ops;
130 static const struct proto_ops msg_ops;
131 static struct proto tipc_proto;
132 
133 static const struct rhashtable_params tsk_rht_params;
134 
135 /*
136  * Revised TIPC socket locking policy:
137  *
138  * Most socket operations take the standard socket lock when they start
139  * and hold it until they finish (or until they need to sleep).  Acquiring
140  * this lock grants the owner exclusive access to the fields of the socket
141  * data structures, with the exception of the backlog queue.  A few socket
142  * operations can be done without taking the socket lock because they only
143  * read socket information that never changes during the life of the socket.
144  *
145  * Socket operations may acquire the lock for the associated TIPC port if they
146  * need to perform an operation on the port.  If any routine needs to acquire
147  * both the socket lock and the port lock it must take the socket lock first
148  * to avoid the risk of deadlock.
149  *
150  * The dispatcher handling incoming messages cannot grab the socket lock in
151  * the standard fashion, since invoked it runs at the BH level and cannot block.
152  * Instead, it checks to see if the socket lock is currently owned by someone,
153  * and either handles the message itself or adds it to the socket's backlog
154  * queue; in the latter case the queued message is processed once the process
155  * owning the socket lock releases it.
156  *
157  * NOTE: Releasing the socket lock while an operation is sleeping overcomes
158  * the problem of a blocked socket operation preventing any other operations
159  * from occurring.  However, applications must be careful if they have
160  * multiple threads trying to send (or receive) on the same socket, as these
161  * operations might interfere with each other.  For example, doing a connect
162  * and a receive at the same time might allow the receive to consume the
163  * ACK message meant for the connect.  While additional work could be done
164  * to try and overcome this, it doesn't seem to be worthwhile at the present.
165  *
166  * NOTE: Releasing the socket lock while an operation is sleeping also ensures
167  * that another operation that must be performed in a non-blocking manner is
168  * not delayed for very long because the lock has already been taken.
169  *
170  * NOTE: This code assumes that certain fields of a port/socket pair are
171  * constant over its lifetime; such fields can be examined without taking
172  * the socket lock and/or port lock, and do not need to be re-read even
173  * after resuming processing after waiting.  These fields include:
174  *   - socket type
175  *   - pointer to socket sk structure (aka tipc_sock structure)
176  *   - pointer to port structure
177  *   - port reference
178  */
179 
180 static u32 tsk_own_node(struct tipc_sock *tsk)
181 {
182 	return msg_prevnode(&tsk->phdr);
183 }
184 
185 static u32 tsk_peer_node(struct tipc_sock *tsk)
186 {
187 	return msg_destnode(&tsk->phdr);
188 }
189 
190 static u32 tsk_peer_port(struct tipc_sock *tsk)
191 {
192 	return msg_destport(&tsk->phdr);
193 }
194 
195 static  bool tsk_unreliable(struct tipc_sock *tsk)
196 {
197 	return msg_src_droppable(&tsk->phdr) != 0;
198 }
199 
200 static void tsk_set_unreliable(struct tipc_sock *tsk, bool unreliable)
201 {
202 	msg_set_src_droppable(&tsk->phdr, unreliable ? 1 : 0);
203 }
204 
205 static bool tsk_unreturnable(struct tipc_sock *tsk)
206 {
207 	return msg_dest_droppable(&tsk->phdr) != 0;
208 }
209 
210 static void tsk_set_unreturnable(struct tipc_sock *tsk, bool unreturnable)
211 {
212 	msg_set_dest_droppable(&tsk->phdr, unreturnable ? 1 : 0);
213 }
214 
215 static int tsk_importance(struct tipc_sock *tsk)
216 {
217 	return msg_importance(&tsk->phdr);
218 }
219 
220 static int tsk_set_importance(struct tipc_sock *tsk, int imp)
221 {
222 	if (imp > TIPC_CRITICAL_IMPORTANCE)
223 		return -EINVAL;
224 	msg_set_importance(&tsk->phdr, (u32)imp);
225 	return 0;
226 }
227 
228 static struct tipc_sock *tipc_sk(const struct sock *sk)
229 {
230 	return container_of(sk, struct tipc_sock, sk);
231 }
232 
233 static bool tsk_conn_cong(struct tipc_sock *tsk)
234 {
235 	return tsk->snt_unacked >= tsk->snd_win;
236 }
237 
238 /* tsk_blocks(): translate a buffer size in bytes to number of
239  * advertisable blocks, taking into account the ratio truesize(len)/len
240  * We can trust that this ratio is always < 4 for len >= FLOWCTL_BLK_SZ
241  */
242 static u16 tsk_adv_blocks(int len)
243 {
244 	return len / FLOWCTL_BLK_SZ / 4;
245 }
246 
247 /* tsk_inc(): increment counter for sent or received data
248  * - If block based flow control is not supported by peer we
249  *   fall back to message based ditto, incrementing the counter
250  */
251 static u16 tsk_inc(struct tipc_sock *tsk, int msglen)
252 {
253 	if (likely(tsk->peer_caps & TIPC_BLOCK_FLOWCTL))
254 		return ((msglen / FLOWCTL_BLK_SZ) + 1);
255 	return 1;
256 }
257 
258 /**
259  * tsk_advance_rx_queue - discard first buffer in socket receive queue
260  *
261  * Caller must hold socket lock
262  */
263 static void tsk_advance_rx_queue(struct sock *sk)
264 {
265 	kfree_skb(__skb_dequeue(&sk->sk_receive_queue));
266 }
267 
268 /* tipc_sk_respond() : send response message back to sender
269  */
270 static void tipc_sk_respond(struct sock *sk, struct sk_buff *skb, int err)
271 {
272 	u32 selector;
273 	u32 dnode;
274 	u32 onode = tipc_own_addr(sock_net(sk));
275 
276 	if (!tipc_msg_reverse(onode, &skb, err))
277 		return;
278 
279 	dnode = msg_destnode(buf_msg(skb));
280 	selector = msg_origport(buf_msg(skb));
281 	tipc_node_xmit_skb(sock_net(sk), skb, dnode, selector);
282 }
283 
284 /**
285  * tsk_rej_rx_queue - reject all buffers in socket receive queue
286  *
287  * Caller must hold socket lock
288  */
289 static void tsk_rej_rx_queue(struct sock *sk)
290 {
291 	struct sk_buff *skb;
292 
293 	while ((skb = __skb_dequeue(&sk->sk_receive_queue)))
294 		tipc_sk_respond(sk, skb, TIPC_ERR_NO_PORT);
295 }
296 
297 /* tsk_peer_msg - verify if message was sent by connected port's peer
298  *
299  * Handles cases where the node's network address has changed from
300  * the default of <0.0.0> to its configured setting.
301  */
302 static bool tsk_peer_msg(struct tipc_sock *tsk, struct tipc_msg *msg)
303 {
304 	struct tipc_net *tn = net_generic(sock_net(&tsk->sk), tipc_net_id);
305 	u32 peer_port = tsk_peer_port(tsk);
306 	u32 orig_node;
307 	u32 peer_node;
308 
309 	if (unlikely(!tsk->connected))
310 		return false;
311 
312 	if (unlikely(msg_origport(msg) != peer_port))
313 		return false;
314 
315 	orig_node = msg_orignode(msg);
316 	peer_node = tsk_peer_node(tsk);
317 
318 	if (likely(orig_node == peer_node))
319 		return true;
320 
321 	if (!orig_node && (peer_node == tn->own_addr))
322 		return true;
323 
324 	if (!peer_node && (orig_node == tn->own_addr))
325 		return true;
326 
327 	return false;
328 }
329 
330 /**
331  * tipc_sk_create - create a TIPC socket
332  * @net: network namespace (must be default network)
333  * @sock: pre-allocated socket structure
334  * @protocol: protocol indicator (must be 0)
335  * @kern: caused by kernel or by userspace?
336  *
337  * This routine creates additional data structures used by the TIPC socket,
338  * initializes them, and links them together.
339  *
340  * Returns 0 on success, errno otherwise
341  */
342 static int tipc_sk_create(struct net *net, struct socket *sock,
343 			  int protocol, int kern)
344 {
345 	struct tipc_net *tn;
346 	const struct proto_ops *ops;
347 	socket_state state;
348 	struct sock *sk;
349 	struct tipc_sock *tsk;
350 	struct tipc_msg *msg;
351 
352 	/* Validate arguments */
353 	if (unlikely(protocol != 0))
354 		return -EPROTONOSUPPORT;
355 
356 	switch (sock->type) {
357 	case SOCK_STREAM:
358 		ops = &stream_ops;
359 		state = SS_UNCONNECTED;
360 		break;
361 	case SOCK_SEQPACKET:
362 		ops = &packet_ops;
363 		state = SS_UNCONNECTED;
364 		break;
365 	case SOCK_DGRAM:
366 	case SOCK_RDM:
367 		ops = &msg_ops;
368 		state = SS_READY;
369 		break;
370 	default:
371 		return -EPROTOTYPE;
372 	}
373 
374 	/* Allocate socket's protocol area */
375 	sk = sk_alloc(net, AF_TIPC, GFP_KERNEL, &tipc_proto, kern);
376 	if (sk == NULL)
377 		return -ENOMEM;
378 
379 	tsk = tipc_sk(sk);
380 	tsk->max_pkt = MAX_PKT_DEFAULT;
381 	INIT_LIST_HEAD(&tsk->publications);
382 	msg = &tsk->phdr;
383 	tn = net_generic(sock_net(sk), tipc_net_id);
384 	tipc_msg_init(tn->own_addr, msg, TIPC_LOW_IMPORTANCE, TIPC_NAMED_MSG,
385 		      NAMED_H_SIZE, 0);
386 
387 	/* Finish initializing socket data structures */
388 	sock->ops = ops;
389 	sock->state = state;
390 	sock_init_data(sock, sk);
391 	if (tipc_sk_insert(tsk)) {
392 		pr_warn("Socket create failed; port number exhausted\n");
393 		return -EINVAL;
394 	}
395 	msg_set_origport(msg, tsk->portid);
396 	setup_timer(&sk->sk_timer, tipc_sk_timeout, (unsigned long)tsk);
397 	sk->sk_backlog_rcv = tipc_backlog_rcv;
398 	sk->sk_rcvbuf = sysctl_tipc_rmem[1];
399 	sk->sk_data_ready = tipc_data_ready;
400 	sk->sk_write_space = tipc_write_space;
401 	sk->sk_destruct = tipc_sock_destruct;
402 	tsk->conn_timeout = CONN_TIMEOUT_DEFAULT;
403 	atomic_set(&tsk->dupl_rcvcnt, 0);
404 
405 	/* Start out with safe limits until we receive an advertised window */
406 	tsk->snd_win = tsk_adv_blocks(RCVBUF_MIN);
407 	tsk->rcv_win = tsk->snd_win;
408 
409 	if (sock->state == SS_READY) {
410 		tsk_set_unreturnable(tsk, true);
411 		if (sock->type == SOCK_DGRAM)
412 			tsk_set_unreliable(tsk, true);
413 	}
414 	return 0;
415 }
416 
417 static void tipc_sk_callback(struct rcu_head *head)
418 {
419 	struct tipc_sock *tsk = container_of(head, struct tipc_sock, rcu);
420 
421 	sock_put(&tsk->sk);
422 }
423 
424 /**
425  * tipc_release - destroy a TIPC socket
426  * @sock: socket to destroy
427  *
428  * This routine cleans up any messages that are still queued on the socket.
429  * For DGRAM and RDM socket types, all queued messages are rejected.
430  * For SEQPACKET and STREAM socket types, the first message is rejected
431  * and any others are discarded.  (If the first message on a STREAM socket
432  * is partially-read, it is discarded and the next one is rejected instead.)
433  *
434  * NOTE: Rejected messages are not necessarily returned to the sender!  They
435  * are returned or discarded according to the "destination droppable" setting
436  * specified for the message by the sender.
437  *
438  * Returns 0 on success, errno otherwise
439  */
440 static int tipc_release(struct socket *sock)
441 {
442 	struct sock *sk = sock->sk;
443 	struct net *net;
444 	struct tipc_sock *tsk;
445 	struct sk_buff *skb;
446 	u32 dnode;
447 
448 	/*
449 	 * Exit if socket isn't fully initialized (occurs when a failed accept()
450 	 * releases a pre-allocated child socket that was never used)
451 	 */
452 	if (sk == NULL)
453 		return 0;
454 
455 	net = sock_net(sk);
456 	tsk = tipc_sk(sk);
457 	lock_sock(sk);
458 
459 	/*
460 	 * Reject all unreceived messages, except on an active connection
461 	 * (which disconnects locally & sends a 'FIN+' to peer)
462 	 */
463 	dnode = tsk_peer_node(tsk);
464 	while (sock->state != SS_DISCONNECTING) {
465 		skb = __skb_dequeue(&sk->sk_receive_queue);
466 		if (skb == NULL)
467 			break;
468 		if (TIPC_SKB_CB(skb)->handle != NULL)
469 			kfree_skb(skb);
470 		else {
471 			if ((sock->state == SS_CONNECTING) ||
472 			    (sock->state == SS_CONNECTED)) {
473 				sock->state = SS_DISCONNECTING;
474 				tsk->connected = 0;
475 				tipc_node_remove_conn(net, dnode, tsk->portid);
476 			}
477 			tipc_sk_respond(sk, skb, TIPC_ERR_NO_PORT);
478 		}
479 	}
480 
481 	tipc_sk_withdraw(tsk, 0, NULL);
482 	sk_stop_timer(sk, &sk->sk_timer);
483 	tipc_sk_remove(tsk);
484 	if (tsk->connected) {
485 		skb = tipc_msg_create(TIPC_CRITICAL_IMPORTANCE,
486 				      TIPC_CONN_MSG, SHORT_H_SIZE, 0, dnode,
487 				      tsk_own_node(tsk), tsk_peer_port(tsk),
488 				      tsk->portid, TIPC_ERR_NO_PORT);
489 		if (skb)
490 			tipc_node_xmit_skb(net, skb, dnode, tsk->portid);
491 		tipc_node_remove_conn(net, dnode, tsk->portid);
492 	}
493 
494 	/* Reject any messages that accumulated in backlog queue */
495 	sock->state = SS_DISCONNECTING;
496 	release_sock(sk);
497 
498 	call_rcu(&tsk->rcu, tipc_sk_callback);
499 	sock->sk = NULL;
500 
501 	return 0;
502 }
503 
504 /**
505  * tipc_bind - associate or disassocate TIPC name(s) with a socket
506  * @sock: socket structure
507  * @uaddr: socket address describing name(s) and desired operation
508  * @uaddr_len: size of socket address data structure
509  *
510  * Name and name sequence binding is indicated using a positive scope value;
511  * a negative scope value unbinds the specified name.  Specifying no name
512  * (i.e. a socket address length of 0) unbinds all names from the socket.
513  *
514  * Returns 0 on success, errno otherwise
515  *
516  * NOTE: This routine doesn't need to take the socket lock since it doesn't
517  *       access any non-constant socket information.
518  */
519 static int tipc_bind(struct socket *sock, struct sockaddr *uaddr,
520 		     int uaddr_len)
521 {
522 	struct sock *sk = sock->sk;
523 	struct sockaddr_tipc *addr = (struct sockaddr_tipc *)uaddr;
524 	struct tipc_sock *tsk = tipc_sk(sk);
525 	int res = -EINVAL;
526 
527 	lock_sock(sk);
528 	if (unlikely(!uaddr_len)) {
529 		res = tipc_sk_withdraw(tsk, 0, NULL);
530 		goto exit;
531 	}
532 
533 	if (uaddr_len < sizeof(struct sockaddr_tipc)) {
534 		res = -EINVAL;
535 		goto exit;
536 	}
537 	if (addr->family != AF_TIPC) {
538 		res = -EAFNOSUPPORT;
539 		goto exit;
540 	}
541 
542 	if (addr->addrtype == TIPC_ADDR_NAME)
543 		addr->addr.nameseq.upper = addr->addr.nameseq.lower;
544 	else if (addr->addrtype != TIPC_ADDR_NAMESEQ) {
545 		res = -EAFNOSUPPORT;
546 		goto exit;
547 	}
548 
549 	if ((addr->addr.nameseq.type < TIPC_RESERVED_TYPES) &&
550 	    (addr->addr.nameseq.type != TIPC_TOP_SRV) &&
551 	    (addr->addr.nameseq.type != TIPC_CFG_SRV)) {
552 		res = -EACCES;
553 		goto exit;
554 	}
555 
556 	res = (addr->scope > 0) ?
557 		tipc_sk_publish(tsk, addr->scope, &addr->addr.nameseq) :
558 		tipc_sk_withdraw(tsk, -addr->scope, &addr->addr.nameseq);
559 exit:
560 	release_sock(sk);
561 	return res;
562 }
563 
564 /**
565  * tipc_getname - get port ID of socket or peer socket
566  * @sock: socket structure
567  * @uaddr: area for returned socket address
568  * @uaddr_len: area for returned length of socket address
569  * @peer: 0 = own ID, 1 = current peer ID, 2 = current/former peer ID
570  *
571  * Returns 0 on success, errno otherwise
572  *
573  * NOTE: This routine doesn't need to take the socket lock since it only
574  *       accesses socket information that is unchanging (or which changes in
575  *       a completely predictable manner).
576  */
577 static int tipc_getname(struct socket *sock, struct sockaddr *uaddr,
578 			int *uaddr_len, int peer)
579 {
580 	struct sockaddr_tipc *addr = (struct sockaddr_tipc *)uaddr;
581 	struct tipc_sock *tsk = tipc_sk(sock->sk);
582 	struct tipc_net *tn = net_generic(sock_net(sock->sk), tipc_net_id);
583 
584 	memset(addr, 0, sizeof(*addr));
585 	if (peer) {
586 		if ((sock->state != SS_CONNECTED) &&
587 			((peer != 2) || (sock->state != SS_DISCONNECTING)))
588 			return -ENOTCONN;
589 		addr->addr.id.ref = tsk_peer_port(tsk);
590 		addr->addr.id.node = tsk_peer_node(tsk);
591 	} else {
592 		addr->addr.id.ref = tsk->portid;
593 		addr->addr.id.node = tn->own_addr;
594 	}
595 
596 	*uaddr_len = sizeof(*addr);
597 	addr->addrtype = TIPC_ADDR_ID;
598 	addr->family = AF_TIPC;
599 	addr->scope = 0;
600 	addr->addr.name.domain = 0;
601 
602 	return 0;
603 }
604 
605 /**
606  * tipc_poll - read and possibly block on pollmask
607  * @file: file structure associated with the socket
608  * @sock: socket for which to calculate the poll bits
609  * @wait: ???
610  *
611  * Returns pollmask value
612  *
613  * COMMENTARY:
614  * It appears that the usual socket locking mechanisms are not useful here
615  * since the pollmask info is potentially out-of-date the moment this routine
616  * exits.  TCP and other protocols seem to rely on higher level poll routines
617  * to handle any preventable race conditions, so TIPC will do the same ...
618  *
619  * TIPC sets the returned events as follows:
620  *
621  * socket state		flags set
622  * ------------		---------
623  * unconnected		no read flags
624  *			POLLOUT if port is not congested
625  *
626  * connecting		POLLIN/POLLRDNORM if ACK/NACK in rx queue
627  *			no write flags
628  *
629  * connected		POLLIN/POLLRDNORM if data in rx queue
630  *			POLLOUT if port is not congested
631  *
632  * disconnecting	POLLIN/POLLRDNORM/POLLHUP
633  *			no write flags
634  *
635  * listening		POLLIN if SYN in rx queue
636  *			no write flags
637  *
638  * ready		POLLIN/POLLRDNORM if data in rx queue
639  * [connectionless]	POLLOUT (since port cannot be congested)
640  *
641  * IMPORTANT: The fact that a read or write operation is indicated does NOT
642  * imply that the operation will succeed, merely that it should be performed
643  * and will not block.
644  */
645 static unsigned int tipc_poll(struct file *file, struct socket *sock,
646 			      poll_table *wait)
647 {
648 	struct sock *sk = sock->sk;
649 	struct tipc_sock *tsk = tipc_sk(sk);
650 	u32 mask = 0;
651 
652 	sock_poll_wait(file, sk_sleep(sk), wait);
653 
654 	switch ((int)sock->state) {
655 	case SS_UNCONNECTED:
656 		if (!tsk->link_cong)
657 			mask |= POLLOUT;
658 		break;
659 	case SS_READY:
660 	case SS_CONNECTED:
661 		if (!tsk->link_cong && !tsk_conn_cong(tsk))
662 			mask |= POLLOUT;
663 		/* fall thru' */
664 	case SS_CONNECTING:
665 	case SS_LISTENING:
666 		if (!skb_queue_empty(&sk->sk_receive_queue))
667 			mask |= (POLLIN | POLLRDNORM);
668 		break;
669 	case SS_DISCONNECTING:
670 		mask = (POLLIN | POLLRDNORM | POLLHUP);
671 		break;
672 	}
673 
674 	return mask;
675 }
676 
677 /**
678  * tipc_sendmcast - send multicast message
679  * @sock: socket structure
680  * @seq: destination address
681  * @msg: message to send
682  * @dsz: total length of message data
683  * @timeo: timeout to wait for wakeup
684  *
685  * Called from function tipc_sendmsg(), which has done all sanity checks
686  * Returns the number of bytes sent on success, or errno
687  */
688 static int tipc_sendmcast(struct  socket *sock, struct tipc_name_seq *seq,
689 			  struct msghdr *msg, size_t dsz, long timeo)
690 {
691 	struct sock *sk = sock->sk;
692 	struct tipc_sock *tsk = tipc_sk(sk);
693 	struct net *net = sock_net(sk);
694 	struct tipc_msg *mhdr = &tsk->phdr;
695 	struct sk_buff_head pktchain;
696 	struct iov_iter save = msg->msg_iter;
697 	uint mtu;
698 	int rc;
699 
700 	msg_set_type(mhdr, TIPC_MCAST_MSG);
701 	msg_set_lookup_scope(mhdr, TIPC_CLUSTER_SCOPE);
702 	msg_set_destport(mhdr, 0);
703 	msg_set_destnode(mhdr, 0);
704 	msg_set_nametype(mhdr, seq->type);
705 	msg_set_namelower(mhdr, seq->lower);
706 	msg_set_nameupper(mhdr, seq->upper);
707 	msg_set_hdr_sz(mhdr, MCAST_H_SIZE);
708 
709 	skb_queue_head_init(&pktchain);
710 
711 new_mtu:
712 	mtu = tipc_bcast_get_mtu(net);
713 	rc = tipc_msg_build(mhdr, msg, 0, dsz, mtu, &pktchain);
714 	if (unlikely(rc < 0))
715 		return rc;
716 
717 	do {
718 		rc = tipc_bcast_xmit(net, &pktchain);
719 		if (likely(!rc))
720 			return dsz;
721 
722 		if (rc == -ELINKCONG) {
723 			tsk->link_cong = 1;
724 			rc = tipc_wait_for_sndmsg(sock, &timeo);
725 			if (!rc)
726 				continue;
727 		}
728 		__skb_queue_purge(&pktchain);
729 		if (rc == -EMSGSIZE) {
730 			msg->msg_iter = save;
731 			goto new_mtu;
732 		}
733 		break;
734 	} while (1);
735 	return rc;
736 }
737 
738 /**
739  * tipc_sk_mcast_rcv - Deliver multicast messages to all destination sockets
740  * @arrvq: queue with arriving messages, to be cloned after destination lookup
741  * @inputq: queue with cloned messages, delivered to socket after dest lookup
742  *
743  * Multi-threaded: parallel calls with reference to same queues may occur
744  */
745 void tipc_sk_mcast_rcv(struct net *net, struct sk_buff_head *arrvq,
746 		       struct sk_buff_head *inputq)
747 {
748 	struct tipc_msg *msg;
749 	struct tipc_plist dports;
750 	u32 portid;
751 	u32 scope = TIPC_CLUSTER_SCOPE;
752 	struct sk_buff_head tmpq;
753 	uint hsz;
754 	struct sk_buff *skb, *_skb;
755 
756 	__skb_queue_head_init(&tmpq);
757 	tipc_plist_init(&dports);
758 
759 	skb = tipc_skb_peek(arrvq, &inputq->lock);
760 	for (; skb; skb = tipc_skb_peek(arrvq, &inputq->lock)) {
761 		msg = buf_msg(skb);
762 		hsz = skb_headroom(skb) + msg_hdr_sz(msg);
763 
764 		if (in_own_node(net, msg_orignode(msg)))
765 			scope = TIPC_NODE_SCOPE;
766 
767 		/* Create destination port list and message clones: */
768 		tipc_nametbl_mc_translate(net,
769 					  msg_nametype(msg), msg_namelower(msg),
770 					  msg_nameupper(msg), scope, &dports);
771 		portid = tipc_plist_pop(&dports);
772 		for (; portid; portid = tipc_plist_pop(&dports)) {
773 			_skb = __pskb_copy(skb, hsz, GFP_ATOMIC);
774 			if (_skb) {
775 				msg_set_destport(buf_msg(_skb), portid);
776 				__skb_queue_tail(&tmpq, _skb);
777 				continue;
778 			}
779 			pr_warn("Failed to clone mcast rcv buffer\n");
780 		}
781 		/* Append to inputq if not already done by other thread */
782 		spin_lock_bh(&inputq->lock);
783 		if (skb_peek(arrvq) == skb) {
784 			skb_queue_splice_tail_init(&tmpq, inputq);
785 			kfree_skb(__skb_dequeue(arrvq));
786 		}
787 		spin_unlock_bh(&inputq->lock);
788 		__skb_queue_purge(&tmpq);
789 		kfree_skb(skb);
790 	}
791 	tipc_sk_rcv(net, inputq);
792 }
793 
794 /**
795  * tipc_sk_proto_rcv - receive a connection mng protocol message
796  * @tsk: receiving socket
797  * @skb: pointer to message buffer.
798  */
799 static void tipc_sk_proto_rcv(struct tipc_sock *tsk, struct sk_buff *skb,
800 			      struct sk_buff_head *xmitq)
801 {
802 	struct sock *sk = &tsk->sk;
803 	u32 onode = tsk_own_node(tsk);
804 	struct tipc_msg *hdr = buf_msg(skb);
805 	int mtyp = msg_type(hdr);
806 	bool conn_cong;
807 
808 	/* Ignore if connection cannot be validated: */
809 	if (!tsk_peer_msg(tsk, hdr))
810 		goto exit;
811 
812 	tsk->probing_state = TIPC_CONN_OK;
813 
814 	if (mtyp == CONN_PROBE) {
815 		msg_set_type(hdr, CONN_PROBE_REPLY);
816 		if (tipc_msg_reverse(onode, &skb, TIPC_OK))
817 			__skb_queue_tail(xmitq, skb);
818 		return;
819 	} else if (mtyp == CONN_ACK) {
820 		conn_cong = tsk_conn_cong(tsk);
821 		tsk->snt_unacked -= msg_conn_ack(hdr);
822 		if (tsk->peer_caps & TIPC_BLOCK_FLOWCTL)
823 			tsk->snd_win = msg_adv_win(hdr);
824 		if (conn_cong)
825 			sk->sk_write_space(sk);
826 	} else if (mtyp != CONN_PROBE_REPLY) {
827 		pr_warn("Received unknown CONN_PROTO msg\n");
828 	}
829 exit:
830 	kfree_skb(skb);
831 }
832 
833 static int tipc_wait_for_sndmsg(struct socket *sock, long *timeo_p)
834 {
835 	struct sock *sk = sock->sk;
836 	struct tipc_sock *tsk = tipc_sk(sk);
837 	DEFINE_WAIT(wait);
838 	int done;
839 
840 	do {
841 		int err = sock_error(sk);
842 		if (err)
843 			return err;
844 		if (sock->state == SS_DISCONNECTING)
845 			return -EPIPE;
846 		if (!*timeo_p)
847 			return -EAGAIN;
848 		if (signal_pending(current))
849 			return sock_intr_errno(*timeo_p);
850 
851 		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
852 		done = sk_wait_event(sk, timeo_p, !tsk->link_cong);
853 		finish_wait(sk_sleep(sk), &wait);
854 	} while (!done);
855 	return 0;
856 }
857 
858 /**
859  * tipc_sendmsg - send message in connectionless manner
860  * @sock: socket structure
861  * @m: message to send
862  * @dsz: amount of user data to be sent
863  *
864  * Message must have an destination specified explicitly.
865  * Used for SOCK_RDM and SOCK_DGRAM messages,
866  * and for 'SYN' messages on SOCK_SEQPACKET and SOCK_STREAM connections.
867  * (Note: 'SYN+' is prohibited on SOCK_STREAM.)
868  *
869  * Returns the number of bytes sent on success, or errno otherwise
870  */
871 static int tipc_sendmsg(struct socket *sock,
872 			struct msghdr *m, size_t dsz)
873 {
874 	struct sock *sk = sock->sk;
875 	int ret;
876 
877 	lock_sock(sk);
878 	ret = __tipc_sendmsg(sock, m, dsz);
879 	release_sock(sk);
880 
881 	return ret;
882 }
883 
884 static int __tipc_sendmsg(struct socket *sock, struct msghdr *m, size_t dsz)
885 {
886 	DECLARE_SOCKADDR(struct sockaddr_tipc *, dest, m->msg_name);
887 	struct sock *sk = sock->sk;
888 	struct tipc_sock *tsk = tipc_sk(sk);
889 	struct net *net = sock_net(sk);
890 	struct tipc_msg *mhdr = &tsk->phdr;
891 	u32 dnode, dport;
892 	struct sk_buff_head pktchain;
893 	struct sk_buff *skb;
894 	struct tipc_name_seq *seq;
895 	struct iov_iter save;
896 	u32 mtu;
897 	long timeo;
898 	int rc;
899 
900 	if (dsz > TIPC_MAX_USER_MSG_SIZE)
901 		return -EMSGSIZE;
902 	if (unlikely(!dest)) {
903 		if (tsk->connected && sock->state == SS_READY)
904 			dest = &tsk->remote;
905 		else
906 			return -EDESTADDRREQ;
907 	} else if (unlikely(m->msg_namelen < sizeof(*dest)) ||
908 		   dest->family != AF_TIPC) {
909 		return -EINVAL;
910 	}
911 	if (unlikely(sock->state != SS_READY)) {
912 		if (sock->state == SS_LISTENING)
913 			return -EPIPE;
914 		if (sock->state != SS_UNCONNECTED)
915 			return -EISCONN;
916 		if (tsk->published)
917 			return -EOPNOTSUPP;
918 		if (dest->addrtype == TIPC_ADDR_NAME) {
919 			tsk->conn_type = dest->addr.name.name.type;
920 			tsk->conn_instance = dest->addr.name.name.instance;
921 		}
922 	}
923 	seq = &dest->addr.nameseq;
924 	timeo = sock_sndtimeo(sk, m->msg_flags & MSG_DONTWAIT);
925 
926 	if (dest->addrtype == TIPC_ADDR_MCAST) {
927 		return tipc_sendmcast(sock, seq, m, dsz, timeo);
928 	} else if (dest->addrtype == TIPC_ADDR_NAME) {
929 		u32 type = dest->addr.name.name.type;
930 		u32 inst = dest->addr.name.name.instance;
931 		u32 domain = dest->addr.name.domain;
932 
933 		dnode = domain;
934 		msg_set_type(mhdr, TIPC_NAMED_MSG);
935 		msg_set_hdr_sz(mhdr, NAMED_H_SIZE);
936 		msg_set_nametype(mhdr, type);
937 		msg_set_nameinst(mhdr, inst);
938 		msg_set_lookup_scope(mhdr, tipc_addr_scope(domain));
939 		dport = tipc_nametbl_translate(net, type, inst, &dnode);
940 		msg_set_destnode(mhdr, dnode);
941 		msg_set_destport(mhdr, dport);
942 		if (unlikely(!dport && !dnode))
943 			return -EHOSTUNREACH;
944 	} else if (dest->addrtype == TIPC_ADDR_ID) {
945 		dnode = dest->addr.id.node;
946 		msg_set_type(mhdr, TIPC_DIRECT_MSG);
947 		msg_set_lookup_scope(mhdr, 0);
948 		msg_set_destnode(mhdr, dnode);
949 		msg_set_destport(mhdr, dest->addr.id.ref);
950 		msg_set_hdr_sz(mhdr, BASIC_H_SIZE);
951 	}
952 
953 	skb_queue_head_init(&pktchain);
954 	save = m->msg_iter;
955 new_mtu:
956 	mtu = tipc_node_get_mtu(net, dnode, tsk->portid);
957 	rc = tipc_msg_build(mhdr, m, 0, dsz, mtu, &pktchain);
958 	if (rc < 0)
959 		return rc;
960 
961 	do {
962 		skb = skb_peek(&pktchain);
963 		TIPC_SKB_CB(skb)->wakeup_pending = tsk->link_cong;
964 		rc = tipc_node_xmit(net, &pktchain, dnode, tsk->portid);
965 		if (likely(!rc)) {
966 			if (sock->state != SS_READY)
967 				sock->state = SS_CONNECTING;
968 			return dsz;
969 		}
970 		if (rc == -ELINKCONG) {
971 			tsk->link_cong = 1;
972 			rc = tipc_wait_for_sndmsg(sock, &timeo);
973 			if (!rc)
974 				continue;
975 		}
976 		__skb_queue_purge(&pktchain);
977 		if (rc == -EMSGSIZE) {
978 			m->msg_iter = save;
979 			goto new_mtu;
980 		}
981 		break;
982 	} while (1);
983 
984 	return rc;
985 }
986 
987 static int tipc_wait_for_sndpkt(struct socket *sock, long *timeo_p)
988 {
989 	struct sock *sk = sock->sk;
990 	struct tipc_sock *tsk = tipc_sk(sk);
991 	DEFINE_WAIT(wait);
992 	int done;
993 
994 	do {
995 		int err = sock_error(sk);
996 		if (err)
997 			return err;
998 		if (sock->state == SS_DISCONNECTING)
999 			return -EPIPE;
1000 		else if (sock->state != SS_CONNECTED)
1001 			return -ENOTCONN;
1002 		if (!*timeo_p)
1003 			return -EAGAIN;
1004 		if (signal_pending(current))
1005 			return sock_intr_errno(*timeo_p);
1006 
1007 		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1008 		done = sk_wait_event(sk, timeo_p,
1009 				     (!tsk->link_cong &&
1010 				      !tsk_conn_cong(tsk)) ||
1011 				     !tsk->connected);
1012 		finish_wait(sk_sleep(sk), &wait);
1013 	} while (!done);
1014 	return 0;
1015 }
1016 
1017 /**
1018  * tipc_send_stream - send stream-oriented data
1019  * @sock: socket structure
1020  * @m: data to send
1021  * @dsz: total length of data to be transmitted
1022  *
1023  * Used for SOCK_STREAM data.
1024  *
1025  * Returns the number of bytes sent on success (or partial success),
1026  * or errno if no data sent
1027  */
1028 static int tipc_send_stream(struct socket *sock, struct msghdr *m, size_t dsz)
1029 {
1030 	struct sock *sk = sock->sk;
1031 	int ret;
1032 
1033 	lock_sock(sk);
1034 	ret = __tipc_send_stream(sock, m, dsz);
1035 	release_sock(sk);
1036 
1037 	return ret;
1038 }
1039 
1040 static int __tipc_send_stream(struct socket *sock, struct msghdr *m, size_t dsz)
1041 {
1042 	struct sock *sk = sock->sk;
1043 	struct net *net = sock_net(sk);
1044 	struct tipc_sock *tsk = tipc_sk(sk);
1045 	struct tipc_msg *mhdr = &tsk->phdr;
1046 	struct sk_buff_head pktchain;
1047 	DECLARE_SOCKADDR(struct sockaddr_tipc *, dest, m->msg_name);
1048 	u32 portid = tsk->portid;
1049 	int rc = -EINVAL;
1050 	long timeo;
1051 	u32 dnode;
1052 	uint mtu, send, sent = 0;
1053 	struct iov_iter save;
1054 	int hlen = MIN_H_SIZE;
1055 
1056 	/* Handle implied connection establishment */
1057 	if (unlikely(dest)) {
1058 		rc = __tipc_sendmsg(sock, m, dsz);
1059 		hlen = msg_hdr_sz(mhdr);
1060 		if (dsz && (dsz == rc))
1061 			tsk->snt_unacked = tsk_inc(tsk, dsz + hlen);
1062 		return rc;
1063 	}
1064 	if (dsz > (uint)INT_MAX)
1065 		return -EMSGSIZE;
1066 
1067 	if (unlikely(sock->state != SS_CONNECTED)) {
1068 		if (sock->state == SS_DISCONNECTING)
1069 			return -EPIPE;
1070 		else
1071 			return -ENOTCONN;
1072 	}
1073 
1074 	timeo = sock_sndtimeo(sk, m->msg_flags & MSG_DONTWAIT);
1075 	dnode = tsk_peer_node(tsk);
1076 	skb_queue_head_init(&pktchain);
1077 
1078 next:
1079 	save = m->msg_iter;
1080 	mtu = tsk->max_pkt;
1081 	send = min_t(uint, dsz - sent, TIPC_MAX_USER_MSG_SIZE);
1082 	rc = tipc_msg_build(mhdr, m, sent, send, mtu, &pktchain);
1083 	if (unlikely(rc < 0))
1084 		return rc;
1085 
1086 	do {
1087 		if (likely(!tsk_conn_cong(tsk))) {
1088 			rc = tipc_node_xmit(net, &pktchain, dnode, portid);
1089 			if (likely(!rc)) {
1090 				tsk->snt_unacked += tsk_inc(tsk, send + hlen);
1091 				sent += send;
1092 				if (sent == dsz)
1093 					return dsz;
1094 				goto next;
1095 			}
1096 			if (rc == -EMSGSIZE) {
1097 				__skb_queue_purge(&pktchain);
1098 				tsk->max_pkt = tipc_node_get_mtu(net, dnode,
1099 								 portid);
1100 				m->msg_iter = save;
1101 				goto next;
1102 			}
1103 			if (rc != -ELINKCONG)
1104 				break;
1105 
1106 			tsk->link_cong = 1;
1107 		}
1108 		rc = tipc_wait_for_sndpkt(sock, &timeo);
1109 	} while (!rc);
1110 
1111 	__skb_queue_purge(&pktchain);
1112 	return sent ? sent : rc;
1113 }
1114 
1115 /**
1116  * tipc_send_packet - send a connection-oriented message
1117  * @sock: socket structure
1118  * @m: message to send
1119  * @dsz: length of data to be transmitted
1120  *
1121  * Used for SOCK_SEQPACKET messages.
1122  *
1123  * Returns the number of bytes sent on success, or errno otherwise
1124  */
1125 static int tipc_send_packet(struct socket *sock, struct msghdr *m, size_t dsz)
1126 {
1127 	if (dsz > TIPC_MAX_USER_MSG_SIZE)
1128 		return -EMSGSIZE;
1129 
1130 	return tipc_send_stream(sock, m, dsz);
1131 }
1132 
1133 /* tipc_sk_finish_conn - complete the setup of a connection
1134  */
1135 static void tipc_sk_finish_conn(struct tipc_sock *tsk, u32 peer_port,
1136 				u32 peer_node)
1137 {
1138 	struct sock *sk = &tsk->sk;
1139 	struct net *net = sock_net(sk);
1140 	struct tipc_msg *msg = &tsk->phdr;
1141 
1142 	msg_set_destnode(msg, peer_node);
1143 	msg_set_destport(msg, peer_port);
1144 	msg_set_type(msg, TIPC_CONN_MSG);
1145 	msg_set_lookup_scope(msg, 0);
1146 	msg_set_hdr_sz(msg, SHORT_H_SIZE);
1147 
1148 	tsk->probing_intv = CONN_PROBING_INTERVAL;
1149 	tsk->probing_state = TIPC_CONN_OK;
1150 	tsk->connected = 1;
1151 	sk_reset_timer(sk, &sk->sk_timer, jiffies + tsk->probing_intv);
1152 	tipc_node_add_conn(net, peer_node, tsk->portid, peer_port);
1153 	tsk->max_pkt = tipc_node_get_mtu(net, peer_node, tsk->portid);
1154 	tsk->peer_caps = tipc_node_get_capabilities(net, peer_node);
1155 	if (tsk->peer_caps & TIPC_BLOCK_FLOWCTL)
1156 		return;
1157 
1158 	/* Fall back to message based flow control */
1159 	tsk->rcv_win = FLOWCTL_MSG_WIN;
1160 	tsk->snd_win = FLOWCTL_MSG_WIN;
1161 }
1162 
1163 /**
1164  * set_orig_addr - capture sender's address for received message
1165  * @m: descriptor for message info
1166  * @msg: received message header
1167  *
1168  * Note: Address is not captured if not requested by receiver.
1169  */
1170 static void set_orig_addr(struct msghdr *m, struct tipc_msg *msg)
1171 {
1172 	DECLARE_SOCKADDR(struct sockaddr_tipc *, addr, m->msg_name);
1173 
1174 	if (addr) {
1175 		addr->family = AF_TIPC;
1176 		addr->addrtype = TIPC_ADDR_ID;
1177 		memset(&addr->addr, 0, sizeof(addr->addr));
1178 		addr->addr.id.ref = msg_origport(msg);
1179 		addr->addr.id.node = msg_orignode(msg);
1180 		addr->addr.name.domain = 0;	/* could leave uninitialized */
1181 		addr->scope = 0;		/* could leave uninitialized */
1182 		m->msg_namelen = sizeof(struct sockaddr_tipc);
1183 	}
1184 }
1185 
1186 /**
1187  * tipc_sk_anc_data_recv - optionally capture ancillary data for received message
1188  * @m: descriptor for message info
1189  * @msg: received message header
1190  * @tsk: TIPC port associated with message
1191  *
1192  * Note: Ancillary data is not captured if not requested by receiver.
1193  *
1194  * Returns 0 if successful, otherwise errno
1195  */
1196 static int tipc_sk_anc_data_recv(struct msghdr *m, struct tipc_msg *msg,
1197 				 struct tipc_sock *tsk)
1198 {
1199 	u32 anc_data[3];
1200 	u32 err;
1201 	u32 dest_type;
1202 	int has_name;
1203 	int res;
1204 
1205 	if (likely(m->msg_controllen == 0))
1206 		return 0;
1207 
1208 	/* Optionally capture errored message object(s) */
1209 	err = msg ? msg_errcode(msg) : 0;
1210 	if (unlikely(err)) {
1211 		anc_data[0] = err;
1212 		anc_data[1] = msg_data_sz(msg);
1213 		res = put_cmsg(m, SOL_TIPC, TIPC_ERRINFO, 8, anc_data);
1214 		if (res)
1215 			return res;
1216 		if (anc_data[1]) {
1217 			res = put_cmsg(m, SOL_TIPC, TIPC_RETDATA, anc_data[1],
1218 				       msg_data(msg));
1219 			if (res)
1220 				return res;
1221 		}
1222 	}
1223 
1224 	/* Optionally capture message destination object */
1225 	dest_type = msg ? msg_type(msg) : TIPC_DIRECT_MSG;
1226 	switch (dest_type) {
1227 	case TIPC_NAMED_MSG:
1228 		has_name = 1;
1229 		anc_data[0] = msg_nametype(msg);
1230 		anc_data[1] = msg_namelower(msg);
1231 		anc_data[2] = msg_namelower(msg);
1232 		break;
1233 	case TIPC_MCAST_MSG:
1234 		has_name = 1;
1235 		anc_data[0] = msg_nametype(msg);
1236 		anc_data[1] = msg_namelower(msg);
1237 		anc_data[2] = msg_nameupper(msg);
1238 		break;
1239 	case TIPC_CONN_MSG:
1240 		has_name = (tsk->conn_type != 0);
1241 		anc_data[0] = tsk->conn_type;
1242 		anc_data[1] = tsk->conn_instance;
1243 		anc_data[2] = tsk->conn_instance;
1244 		break;
1245 	default:
1246 		has_name = 0;
1247 	}
1248 	if (has_name) {
1249 		res = put_cmsg(m, SOL_TIPC, TIPC_DESTNAME, 12, anc_data);
1250 		if (res)
1251 			return res;
1252 	}
1253 
1254 	return 0;
1255 }
1256 
1257 static void tipc_sk_send_ack(struct tipc_sock *tsk)
1258 {
1259 	struct net *net = sock_net(&tsk->sk);
1260 	struct sk_buff *skb = NULL;
1261 	struct tipc_msg *msg;
1262 	u32 peer_port = tsk_peer_port(tsk);
1263 	u32 dnode = tsk_peer_node(tsk);
1264 
1265 	if (!tsk->connected)
1266 		return;
1267 	skb = tipc_msg_create(CONN_MANAGER, CONN_ACK, INT_H_SIZE, 0,
1268 			      dnode, tsk_own_node(tsk), peer_port,
1269 			      tsk->portid, TIPC_OK);
1270 	if (!skb)
1271 		return;
1272 	msg = buf_msg(skb);
1273 	msg_set_conn_ack(msg, tsk->rcv_unacked);
1274 	tsk->rcv_unacked = 0;
1275 
1276 	/* Adjust to and advertize the correct window limit */
1277 	if (tsk->peer_caps & TIPC_BLOCK_FLOWCTL) {
1278 		tsk->rcv_win = tsk_adv_blocks(tsk->sk.sk_rcvbuf);
1279 		msg_set_adv_win(msg, tsk->rcv_win);
1280 	}
1281 	tipc_node_xmit_skb(net, skb, dnode, msg_link_selector(msg));
1282 }
1283 
1284 static int tipc_wait_for_rcvmsg(struct socket *sock, long *timeop)
1285 {
1286 	struct sock *sk = sock->sk;
1287 	DEFINE_WAIT(wait);
1288 	long timeo = *timeop;
1289 	int err;
1290 
1291 	for (;;) {
1292 		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1293 		if (timeo && skb_queue_empty(&sk->sk_receive_queue)) {
1294 			if (sock->state == SS_DISCONNECTING) {
1295 				err = -ENOTCONN;
1296 				break;
1297 			}
1298 			release_sock(sk);
1299 			timeo = schedule_timeout(timeo);
1300 			lock_sock(sk);
1301 		}
1302 		err = 0;
1303 		if (!skb_queue_empty(&sk->sk_receive_queue))
1304 			break;
1305 		err = -EAGAIN;
1306 		if (!timeo)
1307 			break;
1308 		err = sock_intr_errno(timeo);
1309 		if (signal_pending(current))
1310 			break;
1311 	}
1312 	finish_wait(sk_sleep(sk), &wait);
1313 	*timeop = timeo;
1314 	return err;
1315 }
1316 
1317 /**
1318  * tipc_recvmsg - receive packet-oriented message
1319  * @m: descriptor for message info
1320  * @buf_len: total size of user buffer area
1321  * @flags: receive flags
1322  *
1323  * Used for SOCK_DGRAM, SOCK_RDM, and SOCK_SEQPACKET messages.
1324  * If the complete message doesn't fit in user area, truncate it.
1325  *
1326  * Returns size of returned message data, errno otherwise
1327  */
1328 static int tipc_recvmsg(struct socket *sock, struct msghdr *m, size_t buf_len,
1329 			int flags)
1330 {
1331 	struct sock *sk = sock->sk;
1332 	struct tipc_sock *tsk = tipc_sk(sk);
1333 	struct sk_buff *buf;
1334 	struct tipc_msg *msg;
1335 	long timeo;
1336 	unsigned int sz;
1337 	u32 err;
1338 	int res, hlen;
1339 
1340 	/* Catch invalid receive requests */
1341 	if (unlikely(!buf_len))
1342 		return -EINVAL;
1343 
1344 	lock_sock(sk);
1345 
1346 	if (unlikely(sock->state == SS_UNCONNECTED)) {
1347 		res = -ENOTCONN;
1348 		goto exit;
1349 	}
1350 
1351 	timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
1352 restart:
1353 
1354 	/* Look for a message in receive queue; wait if necessary */
1355 	res = tipc_wait_for_rcvmsg(sock, &timeo);
1356 	if (res)
1357 		goto exit;
1358 
1359 	/* Look at first message in receive queue */
1360 	buf = skb_peek(&sk->sk_receive_queue);
1361 	msg = buf_msg(buf);
1362 	sz = msg_data_sz(msg);
1363 	hlen = msg_hdr_sz(msg);
1364 	err = msg_errcode(msg);
1365 
1366 	/* Discard an empty non-errored message & try again */
1367 	if ((!sz) && (!err)) {
1368 		tsk_advance_rx_queue(sk);
1369 		goto restart;
1370 	}
1371 
1372 	/* Capture sender's address (optional) */
1373 	set_orig_addr(m, msg);
1374 
1375 	/* Capture ancillary data (optional) */
1376 	res = tipc_sk_anc_data_recv(m, msg, tsk);
1377 	if (res)
1378 		goto exit;
1379 
1380 	/* Capture message data (if valid) & compute return value (always) */
1381 	if (!err) {
1382 		if (unlikely(buf_len < sz)) {
1383 			sz = buf_len;
1384 			m->msg_flags |= MSG_TRUNC;
1385 		}
1386 		res = skb_copy_datagram_msg(buf, hlen, m, sz);
1387 		if (res)
1388 			goto exit;
1389 		res = sz;
1390 	} else {
1391 		if ((sock->state == SS_READY) ||
1392 		    ((err == TIPC_CONN_SHUTDOWN) || m->msg_control))
1393 			res = 0;
1394 		else
1395 			res = -ECONNRESET;
1396 	}
1397 
1398 	if (unlikely(flags & MSG_PEEK))
1399 		goto exit;
1400 
1401 	if (likely(sock->state != SS_READY)) {
1402 		tsk->rcv_unacked += tsk_inc(tsk, hlen + sz);
1403 		if (unlikely(tsk->rcv_unacked >= (tsk->rcv_win / 4)))
1404 			tipc_sk_send_ack(tsk);
1405 	}
1406 	tsk_advance_rx_queue(sk);
1407 exit:
1408 	release_sock(sk);
1409 	return res;
1410 }
1411 
1412 /**
1413  * tipc_recv_stream - receive stream-oriented data
1414  * @m: descriptor for message info
1415  * @buf_len: total size of user buffer area
1416  * @flags: receive flags
1417  *
1418  * Used for SOCK_STREAM messages only.  If not enough data is available
1419  * will optionally wait for more; never truncates data.
1420  *
1421  * Returns size of returned message data, errno otherwise
1422  */
1423 static int tipc_recv_stream(struct socket *sock, struct msghdr *m,
1424 			    size_t buf_len, int flags)
1425 {
1426 	struct sock *sk = sock->sk;
1427 	struct tipc_sock *tsk = tipc_sk(sk);
1428 	struct sk_buff *buf;
1429 	struct tipc_msg *msg;
1430 	long timeo;
1431 	unsigned int sz;
1432 	int sz_to_copy, target, needed;
1433 	int sz_copied = 0;
1434 	u32 err;
1435 	int res = 0, hlen;
1436 
1437 	/* Catch invalid receive attempts */
1438 	if (unlikely(!buf_len))
1439 		return -EINVAL;
1440 
1441 	lock_sock(sk);
1442 
1443 	if (unlikely(sock->state == SS_UNCONNECTED)) {
1444 		res = -ENOTCONN;
1445 		goto exit;
1446 	}
1447 
1448 	target = sock_rcvlowat(sk, flags & MSG_WAITALL, buf_len);
1449 	timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
1450 
1451 restart:
1452 	/* Look for a message in receive queue; wait if necessary */
1453 	res = tipc_wait_for_rcvmsg(sock, &timeo);
1454 	if (res)
1455 		goto exit;
1456 
1457 	/* Look at first message in receive queue */
1458 	buf = skb_peek(&sk->sk_receive_queue);
1459 	msg = buf_msg(buf);
1460 	sz = msg_data_sz(msg);
1461 	hlen = msg_hdr_sz(msg);
1462 	err = msg_errcode(msg);
1463 
1464 	/* Discard an empty non-errored message & try again */
1465 	if ((!sz) && (!err)) {
1466 		tsk_advance_rx_queue(sk);
1467 		goto restart;
1468 	}
1469 
1470 	/* Optionally capture sender's address & ancillary data of first msg */
1471 	if (sz_copied == 0) {
1472 		set_orig_addr(m, msg);
1473 		res = tipc_sk_anc_data_recv(m, msg, tsk);
1474 		if (res)
1475 			goto exit;
1476 	}
1477 
1478 	/* Capture message data (if valid) & compute return value (always) */
1479 	if (!err) {
1480 		u32 offset = (u32)(unsigned long)(TIPC_SKB_CB(buf)->handle);
1481 
1482 		sz -= offset;
1483 		needed = (buf_len - sz_copied);
1484 		sz_to_copy = (sz <= needed) ? sz : needed;
1485 
1486 		res = skb_copy_datagram_msg(buf, hlen + offset, m, sz_to_copy);
1487 		if (res)
1488 			goto exit;
1489 
1490 		sz_copied += sz_to_copy;
1491 
1492 		if (sz_to_copy < sz) {
1493 			if (!(flags & MSG_PEEK))
1494 				TIPC_SKB_CB(buf)->handle =
1495 				(void *)(unsigned long)(offset + sz_to_copy);
1496 			goto exit;
1497 		}
1498 	} else {
1499 		if (sz_copied != 0)
1500 			goto exit; /* can't add error msg to valid data */
1501 
1502 		if ((err == TIPC_CONN_SHUTDOWN) || m->msg_control)
1503 			res = 0;
1504 		else
1505 			res = -ECONNRESET;
1506 	}
1507 
1508 	if (unlikely(flags & MSG_PEEK))
1509 		goto exit;
1510 
1511 	tsk->rcv_unacked += tsk_inc(tsk, hlen + sz);
1512 	if (unlikely(tsk->rcv_unacked >= (tsk->rcv_win / 4)))
1513 		tipc_sk_send_ack(tsk);
1514 	tsk_advance_rx_queue(sk);
1515 
1516 	/* Loop around if more data is required */
1517 	if ((sz_copied < buf_len) &&	/* didn't get all requested data */
1518 	    (!skb_queue_empty(&sk->sk_receive_queue) ||
1519 	    (sz_copied < target)) &&	/* and more is ready or required */
1520 	    (!err))			/* and haven't reached a FIN */
1521 		goto restart;
1522 
1523 exit:
1524 	release_sock(sk);
1525 	return sz_copied ? sz_copied : res;
1526 }
1527 
1528 /**
1529  * tipc_write_space - wake up thread if port congestion is released
1530  * @sk: socket
1531  */
1532 static void tipc_write_space(struct sock *sk)
1533 {
1534 	struct socket_wq *wq;
1535 
1536 	rcu_read_lock();
1537 	wq = rcu_dereference(sk->sk_wq);
1538 	if (skwq_has_sleeper(wq))
1539 		wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
1540 						POLLWRNORM | POLLWRBAND);
1541 	rcu_read_unlock();
1542 }
1543 
1544 /**
1545  * tipc_data_ready - wake up threads to indicate messages have been received
1546  * @sk: socket
1547  * @len: the length of messages
1548  */
1549 static void tipc_data_ready(struct sock *sk)
1550 {
1551 	struct socket_wq *wq;
1552 
1553 	rcu_read_lock();
1554 	wq = rcu_dereference(sk->sk_wq);
1555 	if (skwq_has_sleeper(wq))
1556 		wake_up_interruptible_sync_poll(&wq->wait, POLLIN |
1557 						POLLRDNORM | POLLRDBAND);
1558 	rcu_read_unlock();
1559 }
1560 
1561 static void tipc_sock_destruct(struct sock *sk)
1562 {
1563 	__skb_queue_purge(&sk->sk_receive_queue);
1564 }
1565 
1566 /**
1567  * filter_connect - Handle all incoming messages for a connection-based socket
1568  * @tsk: TIPC socket
1569  * @skb: pointer to message buffer. Set to NULL if buffer is consumed
1570  *
1571  * Returns true if everything ok, false otherwise
1572  */
1573 static bool filter_connect(struct tipc_sock *tsk, struct sk_buff *skb)
1574 {
1575 	struct sock *sk = &tsk->sk;
1576 	struct net *net = sock_net(sk);
1577 	struct socket *sock = sk->sk_socket;
1578 	struct tipc_msg *hdr = buf_msg(skb);
1579 
1580 	if (unlikely(msg_mcast(hdr)))
1581 		return false;
1582 
1583 	switch ((int)sock->state) {
1584 	case SS_CONNECTED:
1585 
1586 		/* Accept only connection-based messages sent by peer */
1587 		if (unlikely(!tsk_peer_msg(tsk, hdr)))
1588 			return false;
1589 
1590 		if (unlikely(msg_errcode(hdr))) {
1591 			sock->state = SS_DISCONNECTING;
1592 			tsk->connected = 0;
1593 			/* Let timer expire on it's own */
1594 			tipc_node_remove_conn(net, tsk_peer_node(tsk),
1595 					      tsk->portid);
1596 		}
1597 		return true;
1598 
1599 	case SS_CONNECTING:
1600 
1601 		/* Accept only ACK or NACK message */
1602 		if (unlikely(!msg_connected(hdr)))
1603 			return false;
1604 
1605 		if (unlikely(msg_errcode(hdr))) {
1606 			sock->state = SS_DISCONNECTING;
1607 			sk->sk_err = ECONNREFUSED;
1608 			return true;
1609 		}
1610 
1611 		if (unlikely(!msg_isdata(hdr))) {
1612 			sock->state = SS_DISCONNECTING;
1613 			sk->sk_err = EINVAL;
1614 			return true;
1615 		}
1616 
1617 		tipc_sk_finish_conn(tsk, msg_origport(hdr), msg_orignode(hdr));
1618 		msg_set_importance(&tsk->phdr, msg_importance(hdr));
1619 		sock->state = SS_CONNECTED;
1620 
1621 		/* If 'ACK+' message, add to socket receive queue */
1622 		if (msg_data_sz(hdr))
1623 			return true;
1624 
1625 		/* If empty 'ACK-' message, wake up sleeping connect() */
1626 		if (waitqueue_active(sk_sleep(sk)))
1627 			wake_up_interruptible(sk_sleep(sk));
1628 
1629 		/* 'ACK-' message is neither accepted nor rejected: */
1630 		msg_set_dest_droppable(hdr, 1);
1631 		return false;
1632 
1633 	case SS_LISTENING:
1634 	case SS_UNCONNECTED:
1635 
1636 		/* Accept only SYN message */
1637 		if (!msg_connected(hdr) && !(msg_errcode(hdr)))
1638 			return true;
1639 		break;
1640 	case SS_DISCONNECTING:
1641 		break;
1642 	default:
1643 		pr_err("Unknown socket state %u\n", sock->state);
1644 	}
1645 	return false;
1646 }
1647 
1648 /**
1649  * rcvbuf_limit - get proper overload limit of socket receive queue
1650  * @sk: socket
1651  * @skb: message
1652  *
1653  * For connection oriented messages, irrespective of importance,
1654  * default queue limit is 2 MB.
1655  *
1656  * For connectionless messages, queue limits are based on message
1657  * importance as follows:
1658  *
1659  * TIPC_LOW_IMPORTANCE       (2 MB)
1660  * TIPC_MEDIUM_IMPORTANCE    (4 MB)
1661  * TIPC_HIGH_IMPORTANCE      (8 MB)
1662  * TIPC_CRITICAL_IMPORTANCE  (16 MB)
1663  *
1664  * Returns overload limit according to corresponding message importance
1665  */
1666 static unsigned int rcvbuf_limit(struct sock *sk, struct sk_buff *skb)
1667 {
1668 	struct tipc_sock *tsk = tipc_sk(sk);
1669 	struct tipc_msg *hdr = buf_msg(skb);
1670 
1671 	if (unlikely(!msg_connected(hdr)))
1672 		return sk->sk_rcvbuf << msg_importance(hdr);
1673 
1674 	if (likely(tsk->peer_caps & TIPC_BLOCK_FLOWCTL))
1675 		return sk->sk_rcvbuf;
1676 
1677 	return FLOWCTL_MSG_LIM;
1678 }
1679 
1680 /**
1681  * filter_rcv - validate incoming message
1682  * @sk: socket
1683  * @skb: pointer to message.
1684  *
1685  * Enqueues message on receive queue if acceptable; optionally handles
1686  * disconnect indication for a connected socket.
1687  *
1688  * Called with socket lock already taken
1689  *
1690  * Returns true if message was added to socket receive queue, otherwise false
1691  */
1692 static bool filter_rcv(struct sock *sk, struct sk_buff *skb,
1693 		       struct sk_buff_head *xmitq)
1694 {
1695 	struct socket *sock = sk->sk_socket;
1696 	struct tipc_sock *tsk = tipc_sk(sk);
1697 	struct tipc_msg *hdr = buf_msg(skb);
1698 	unsigned int limit = rcvbuf_limit(sk, skb);
1699 	int err = TIPC_OK;
1700 	int usr = msg_user(hdr);
1701 
1702 	if (unlikely(msg_user(hdr) == CONN_MANAGER)) {
1703 		tipc_sk_proto_rcv(tsk, skb, xmitq);
1704 		return false;
1705 	}
1706 
1707 	if (unlikely(usr == SOCK_WAKEUP)) {
1708 		kfree_skb(skb);
1709 		tsk->link_cong = 0;
1710 		sk->sk_write_space(sk);
1711 		return false;
1712 	}
1713 
1714 	/* Drop if illegal message type */
1715 	if (unlikely(msg_type(hdr) > TIPC_DIRECT_MSG)) {
1716 		kfree_skb(skb);
1717 		return false;
1718 	}
1719 
1720 	/* Reject if wrong message type for current socket state */
1721 	if (unlikely(sock->state == SS_READY)) {
1722 		if (msg_connected(hdr)) {
1723 			err = TIPC_ERR_NO_PORT;
1724 			goto reject;
1725 		}
1726 	} else if (unlikely(!filter_connect(tsk, skb))) {
1727 		err = TIPC_ERR_NO_PORT;
1728 		goto reject;
1729 	}
1730 
1731 	/* Reject message if there isn't room to queue it */
1732 	if (unlikely(sk_rmem_alloc_get(sk) + skb->truesize >= limit)) {
1733 		err = TIPC_ERR_OVERLOAD;
1734 		goto reject;
1735 	}
1736 
1737 	/* Enqueue message */
1738 	TIPC_SKB_CB(skb)->handle = NULL;
1739 	__skb_queue_tail(&sk->sk_receive_queue, skb);
1740 	skb_set_owner_r(skb, sk);
1741 
1742 	sk->sk_data_ready(sk);
1743 	return true;
1744 
1745 reject:
1746 	if (tipc_msg_reverse(tsk_own_node(tsk), &skb, err))
1747 		__skb_queue_tail(xmitq, skb);
1748 	return false;
1749 }
1750 
1751 /**
1752  * tipc_backlog_rcv - handle incoming message from backlog queue
1753  * @sk: socket
1754  * @skb: message
1755  *
1756  * Caller must hold socket lock
1757  *
1758  * Returns 0
1759  */
1760 static int tipc_backlog_rcv(struct sock *sk, struct sk_buff *skb)
1761 {
1762 	unsigned int truesize = skb->truesize;
1763 	struct sk_buff_head xmitq;
1764 	u32 dnode, selector;
1765 
1766 	__skb_queue_head_init(&xmitq);
1767 
1768 	if (likely(filter_rcv(sk, skb, &xmitq))) {
1769 		atomic_add(truesize, &tipc_sk(sk)->dupl_rcvcnt);
1770 		return 0;
1771 	}
1772 
1773 	if (skb_queue_empty(&xmitq))
1774 		return 0;
1775 
1776 	/* Send response/rejected message */
1777 	skb = __skb_dequeue(&xmitq);
1778 	dnode = msg_destnode(buf_msg(skb));
1779 	selector = msg_origport(buf_msg(skb));
1780 	tipc_node_xmit_skb(sock_net(sk), skb, dnode, selector);
1781 	return 0;
1782 }
1783 
1784 /**
1785  * tipc_sk_enqueue - extract all buffers with destination 'dport' from
1786  *                   inputq and try adding them to socket or backlog queue
1787  * @inputq: list of incoming buffers with potentially different destinations
1788  * @sk: socket where the buffers should be enqueued
1789  * @dport: port number for the socket
1790  *
1791  * Caller must hold socket lock
1792  */
1793 static void tipc_sk_enqueue(struct sk_buff_head *inputq, struct sock *sk,
1794 			    u32 dport, struct sk_buff_head *xmitq)
1795 {
1796 	unsigned long time_limit = jiffies + 2;
1797 	struct sk_buff *skb;
1798 	unsigned int lim;
1799 	atomic_t *dcnt;
1800 	u32 onode;
1801 
1802 	while (skb_queue_len(inputq)) {
1803 		if (unlikely(time_after_eq(jiffies, time_limit)))
1804 			return;
1805 
1806 		skb = tipc_skb_dequeue(inputq, dport);
1807 		if (unlikely(!skb))
1808 			return;
1809 
1810 		/* Add message directly to receive queue if possible */
1811 		if (!sock_owned_by_user(sk)) {
1812 			filter_rcv(sk, skb, xmitq);
1813 			continue;
1814 		}
1815 
1816 		/* Try backlog, compensating for double-counted bytes */
1817 		dcnt = &tipc_sk(sk)->dupl_rcvcnt;
1818 		if (!sk->sk_backlog.len)
1819 			atomic_set(dcnt, 0);
1820 		lim = rcvbuf_limit(sk, skb) + atomic_read(dcnt);
1821 		if (likely(!sk_add_backlog(sk, skb, lim)))
1822 			continue;
1823 
1824 		/* Overload => reject message back to sender */
1825 		onode = tipc_own_addr(sock_net(sk));
1826 		if (tipc_msg_reverse(onode, &skb, TIPC_ERR_OVERLOAD))
1827 			__skb_queue_tail(xmitq, skb);
1828 		break;
1829 	}
1830 }
1831 
1832 /**
1833  * tipc_sk_rcv - handle a chain of incoming buffers
1834  * @inputq: buffer list containing the buffers
1835  * Consumes all buffers in list until inputq is empty
1836  * Note: may be called in multiple threads referring to the same queue
1837  */
1838 void tipc_sk_rcv(struct net *net, struct sk_buff_head *inputq)
1839 {
1840 	struct sk_buff_head xmitq;
1841 	u32 dnode, dport = 0;
1842 	int err;
1843 	struct tipc_sock *tsk;
1844 	struct sock *sk;
1845 	struct sk_buff *skb;
1846 
1847 	__skb_queue_head_init(&xmitq);
1848 	while (skb_queue_len(inputq)) {
1849 		dport = tipc_skb_peek_port(inputq, dport);
1850 		tsk = tipc_sk_lookup(net, dport);
1851 
1852 		if (likely(tsk)) {
1853 			sk = &tsk->sk;
1854 			if (likely(spin_trylock_bh(&sk->sk_lock.slock))) {
1855 				tipc_sk_enqueue(inputq, sk, dport, &xmitq);
1856 				spin_unlock_bh(&sk->sk_lock.slock);
1857 			}
1858 			/* Send pending response/rejected messages, if any */
1859 			while ((skb = __skb_dequeue(&xmitq))) {
1860 				dnode = msg_destnode(buf_msg(skb));
1861 				tipc_node_xmit_skb(net, skb, dnode, dport);
1862 			}
1863 			sock_put(sk);
1864 			continue;
1865 		}
1866 
1867 		/* No destination socket => dequeue skb if still there */
1868 		skb = tipc_skb_dequeue(inputq, dport);
1869 		if (!skb)
1870 			return;
1871 
1872 		/* Try secondary lookup if unresolved named message */
1873 		err = TIPC_ERR_NO_PORT;
1874 		if (tipc_msg_lookup_dest(net, skb, &err))
1875 			goto xmit;
1876 
1877 		/* Prepare for message rejection */
1878 		if (!tipc_msg_reverse(tipc_own_addr(net), &skb, err))
1879 			continue;
1880 xmit:
1881 		dnode = msg_destnode(buf_msg(skb));
1882 		tipc_node_xmit_skb(net, skb, dnode, dport);
1883 	}
1884 }
1885 
1886 static int tipc_wait_for_connect(struct socket *sock, long *timeo_p)
1887 {
1888 	struct sock *sk = sock->sk;
1889 	DEFINE_WAIT(wait);
1890 	int done;
1891 
1892 	do {
1893 		int err = sock_error(sk);
1894 		if (err)
1895 			return err;
1896 		if (!*timeo_p)
1897 			return -ETIMEDOUT;
1898 		if (signal_pending(current))
1899 			return sock_intr_errno(*timeo_p);
1900 
1901 		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1902 		done = sk_wait_event(sk, timeo_p, sock->state != SS_CONNECTING);
1903 		finish_wait(sk_sleep(sk), &wait);
1904 	} while (!done);
1905 	return 0;
1906 }
1907 
1908 /**
1909  * tipc_connect - establish a connection to another TIPC port
1910  * @sock: socket structure
1911  * @dest: socket address for destination port
1912  * @destlen: size of socket address data structure
1913  * @flags: file-related flags associated with socket
1914  *
1915  * Returns 0 on success, errno otherwise
1916  */
1917 static int tipc_connect(struct socket *sock, struct sockaddr *dest,
1918 			int destlen, int flags)
1919 {
1920 	struct sock *sk = sock->sk;
1921 	struct tipc_sock *tsk = tipc_sk(sk);
1922 	struct sockaddr_tipc *dst = (struct sockaddr_tipc *)dest;
1923 	struct msghdr m = {NULL,};
1924 	long timeout = (flags & O_NONBLOCK) ? 0 : tsk->conn_timeout;
1925 	socket_state previous;
1926 	int res = 0;
1927 
1928 	lock_sock(sk);
1929 
1930 	/* DGRAM/RDM connect(), just save the destaddr */
1931 	if (sock->state == SS_READY) {
1932 		if (dst->family == AF_UNSPEC) {
1933 			memset(&tsk->remote, 0, sizeof(struct sockaddr_tipc));
1934 			tsk->connected = 0;
1935 		} else if (destlen != sizeof(struct sockaddr_tipc)) {
1936 			res = -EINVAL;
1937 		} else {
1938 			memcpy(&tsk->remote, dest, destlen);
1939 			tsk->connected = 1;
1940 		}
1941 		goto exit;
1942 	}
1943 
1944 	/*
1945 	 * Reject connection attempt using multicast address
1946 	 *
1947 	 * Note: send_msg() validates the rest of the address fields,
1948 	 *       so there's no need to do it here
1949 	 */
1950 	if (dst->addrtype == TIPC_ADDR_MCAST) {
1951 		res = -EINVAL;
1952 		goto exit;
1953 	}
1954 
1955 	previous = sock->state;
1956 	switch (sock->state) {
1957 	case SS_UNCONNECTED:
1958 		/* Send a 'SYN-' to destination */
1959 		m.msg_name = dest;
1960 		m.msg_namelen = destlen;
1961 
1962 		/* If connect is in non-blocking case, set MSG_DONTWAIT to
1963 		 * indicate send_msg() is never blocked.
1964 		 */
1965 		if (!timeout)
1966 			m.msg_flags = MSG_DONTWAIT;
1967 
1968 		res = __tipc_sendmsg(sock, &m, 0);
1969 		if ((res < 0) && (res != -EWOULDBLOCK))
1970 			goto exit;
1971 
1972 		/* Just entered SS_CONNECTING state; the only
1973 		 * difference is that return value in non-blocking
1974 		 * case is EINPROGRESS, rather than EALREADY.
1975 		 */
1976 		res = -EINPROGRESS;
1977 	case SS_CONNECTING:
1978 		if (previous == SS_CONNECTING)
1979 			res = -EALREADY;
1980 		if (!timeout)
1981 			goto exit;
1982 		timeout = msecs_to_jiffies(timeout);
1983 		/* Wait until an 'ACK' or 'RST' arrives, or a timeout occurs */
1984 		res = tipc_wait_for_connect(sock, &timeout);
1985 		break;
1986 	case SS_CONNECTED:
1987 		res = -EISCONN;
1988 		break;
1989 	default:
1990 		res = -EINVAL;
1991 		break;
1992 	}
1993 exit:
1994 	release_sock(sk);
1995 	return res;
1996 }
1997 
1998 /**
1999  * tipc_listen - allow socket to listen for incoming connections
2000  * @sock: socket structure
2001  * @len: (unused)
2002  *
2003  * Returns 0 on success, errno otherwise
2004  */
2005 static int tipc_listen(struct socket *sock, int len)
2006 {
2007 	struct sock *sk = sock->sk;
2008 	int res;
2009 
2010 	lock_sock(sk);
2011 
2012 	if (sock->state != SS_UNCONNECTED)
2013 		res = -EINVAL;
2014 	else {
2015 		sock->state = SS_LISTENING;
2016 		res = 0;
2017 	}
2018 
2019 	release_sock(sk);
2020 	return res;
2021 }
2022 
2023 static int tipc_wait_for_accept(struct socket *sock, long timeo)
2024 {
2025 	struct sock *sk = sock->sk;
2026 	DEFINE_WAIT(wait);
2027 	int err;
2028 
2029 	/* True wake-one mechanism for incoming connections: only
2030 	 * one process gets woken up, not the 'whole herd'.
2031 	 * Since we do not 'race & poll' for established sockets
2032 	 * anymore, the common case will execute the loop only once.
2033 	*/
2034 	for (;;) {
2035 		prepare_to_wait_exclusive(sk_sleep(sk), &wait,
2036 					  TASK_INTERRUPTIBLE);
2037 		if (timeo && skb_queue_empty(&sk->sk_receive_queue)) {
2038 			release_sock(sk);
2039 			timeo = schedule_timeout(timeo);
2040 			lock_sock(sk);
2041 		}
2042 		err = 0;
2043 		if (!skb_queue_empty(&sk->sk_receive_queue))
2044 			break;
2045 		err = -EINVAL;
2046 		if (sock->state != SS_LISTENING)
2047 			break;
2048 		err = -EAGAIN;
2049 		if (!timeo)
2050 			break;
2051 		err = sock_intr_errno(timeo);
2052 		if (signal_pending(current))
2053 			break;
2054 	}
2055 	finish_wait(sk_sleep(sk), &wait);
2056 	return err;
2057 }
2058 
2059 /**
2060  * tipc_accept - wait for connection request
2061  * @sock: listening socket
2062  * @newsock: new socket that is to be connected
2063  * @flags: file-related flags associated with socket
2064  *
2065  * Returns 0 on success, errno otherwise
2066  */
2067 static int tipc_accept(struct socket *sock, struct socket *new_sock, int flags)
2068 {
2069 	struct sock *new_sk, *sk = sock->sk;
2070 	struct sk_buff *buf;
2071 	struct tipc_sock *new_tsock;
2072 	struct tipc_msg *msg;
2073 	long timeo;
2074 	int res;
2075 
2076 	lock_sock(sk);
2077 
2078 	if (sock->state != SS_LISTENING) {
2079 		res = -EINVAL;
2080 		goto exit;
2081 	}
2082 	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
2083 	res = tipc_wait_for_accept(sock, timeo);
2084 	if (res)
2085 		goto exit;
2086 
2087 	buf = skb_peek(&sk->sk_receive_queue);
2088 
2089 	res = tipc_sk_create(sock_net(sock->sk), new_sock, 0, 1);
2090 	if (res)
2091 		goto exit;
2092 	security_sk_clone(sock->sk, new_sock->sk);
2093 
2094 	new_sk = new_sock->sk;
2095 	new_tsock = tipc_sk(new_sk);
2096 	msg = buf_msg(buf);
2097 
2098 	/* we lock on new_sk; but lockdep sees the lock on sk */
2099 	lock_sock_nested(new_sk, SINGLE_DEPTH_NESTING);
2100 
2101 	/*
2102 	 * Reject any stray messages received by new socket
2103 	 * before the socket lock was taken (very, very unlikely)
2104 	 */
2105 	tsk_rej_rx_queue(new_sk);
2106 
2107 	/* Connect new socket to it's peer */
2108 	tipc_sk_finish_conn(new_tsock, msg_origport(msg), msg_orignode(msg));
2109 	new_sock->state = SS_CONNECTED;
2110 
2111 	tsk_set_importance(new_tsock, msg_importance(msg));
2112 	if (msg_named(msg)) {
2113 		new_tsock->conn_type = msg_nametype(msg);
2114 		new_tsock->conn_instance = msg_nameinst(msg);
2115 	}
2116 
2117 	/*
2118 	 * Respond to 'SYN-' by discarding it & returning 'ACK'-.
2119 	 * Respond to 'SYN+' by queuing it on new socket.
2120 	 */
2121 	if (!msg_data_sz(msg)) {
2122 		struct msghdr m = {NULL,};
2123 
2124 		tsk_advance_rx_queue(sk);
2125 		__tipc_send_stream(new_sock, &m, 0);
2126 	} else {
2127 		__skb_dequeue(&sk->sk_receive_queue);
2128 		__skb_queue_head(&new_sk->sk_receive_queue, buf);
2129 		skb_set_owner_r(buf, new_sk);
2130 	}
2131 	release_sock(new_sk);
2132 exit:
2133 	release_sock(sk);
2134 	return res;
2135 }
2136 
2137 /**
2138  * tipc_shutdown - shutdown socket connection
2139  * @sock: socket structure
2140  * @how: direction to close (must be SHUT_RDWR)
2141  *
2142  * Terminates connection (if necessary), then purges socket's receive queue.
2143  *
2144  * Returns 0 on success, errno otherwise
2145  */
2146 static int tipc_shutdown(struct socket *sock, int how)
2147 {
2148 	struct sock *sk = sock->sk;
2149 	struct net *net = sock_net(sk);
2150 	struct tipc_sock *tsk = tipc_sk(sk);
2151 	struct sk_buff *skb;
2152 	u32 dnode = tsk_peer_node(tsk);
2153 	u32 dport = tsk_peer_port(tsk);
2154 	u32 onode = tipc_own_addr(net);
2155 	u32 oport = tsk->portid;
2156 	int res;
2157 
2158 	if (how != SHUT_RDWR)
2159 		return -EINVAL;
2160 
2161 	lock_sock(sk);
2162 
2163 	switch (sock->state) {
2164 	case SS_CONNECTING:
2165 	case SS_CONNECTED:
2166 
2167 restart:
2168 		dnode = tsk_peer_node(tsk);
2169 
2170 		/* Disconnect and send a 'FIN+' or 'FIN-' message to peer */
2171 		skb = __skb_dequeue(&sk->sk_receive_queue);
2172 		if (skb) {
2173 			if (TIPC_SKB_CB(skb)->handle != NULL) {
2174 				kfree_skb(skb);
2175 				goto restart;
2176 			}
2177 			tipc_sk_respond(sk, skb, TIPC_CONN_SHUTDOWN);
2178 		} else {
2179 			skb = tipc_msg_create(TIPC_CRITICAL_IMPORTANCE,
2180 					      TIPC_CONN_MSG, SHORT_H_SIZE,
2181 					      0, dnode, onode, dport, oport,
2182 					      TIPC_CONN_SHUTDOWN);
2183 			if (skb)
2184 				tipc_node_xmit_skb(net, skb, dnode, tsk->portid);
2185 		}
2186 		tsk->connected = 0;
2187 		sock->state = SS_DISCONNECTING;
2188 		tipc_node_remove_conn(net, dnode, tsk->portid);
2189 		/* fall through */
2190 
2191 	case SS_DISCONNECTING:
2192 
2193 		/* Discard any unreceived messages */
2194 		__skb_queue_purge(&sk->sk_receive_queue);
2195 
2196 		/* Wake up anyone sleeping in poll */
2197 		sk->sk_state_change(sk);
2198 		res = 0;
2199 		break;
2200 
2201 	default:
2202 		res = -ENOTCONN;
2203 	}
2204 
2205 	release_sock(sk);
2206 	return res;
2207 }
2208 
2209 static void tipc_sk_timeout(unsigned long data)
2210 {
2211 	struct tipc_sock *tsk = (struct tipc_sock *)data;
2212 	struct sock *sk = &tsk->sk;
2213 	struct sk_buff *skb = NULL;
2214 	u32 peer_port, peer_node;
2215 	u32 own_node = tsk_own_node(tsk);
2216 
2217 	bh_lock_sock(sk);
2218 	if (!tsk->connected) {
2219 		bh_unlock_sock(sk);
2220 		goto exit;
2221 	}
2222 	peer_port = tsk_peer_port(tsk);
2223 	peer_node = tsk_peer_node(tsk);
2224 
2225 	if (tsk->probing_state == TIPC_CONN_PROBING) {
2226 		if (!sock_owned_by_user(sk)) {
2227 			sk->sk_socket->state = SS_DISCONNECTING;
2228 			tsk->connected = 0;
2229 			tipc_node_remove_conn(sock_net(sk), tsk_peer_node(tsk),
2230 					      tsk_peer_port(tsk));
2231 			sk->sk_state_change(sk);
2232 		} else {
2233 			/* Try again later */
2234 			sk_reset_timer(sk, &sk->sk_timer, (HZ / 20));
2235 		}
2236 
2237 	} else {
2238 		skb = tipc_msg_create(CONN_MANAGER, CONN_PROBE,
2239 				      INT_H_SIZE, 0, peer_node, own_node,
2240 				      peer_port, tsk->portid, TIPC_OK);
2241 		tsk->probing_state = TIPC_CONN_PROBING;
2242 		sk_reset_timer(sk, &sk->sk_timer, jiffies + tsk->probing_intv);
2243 	}
2244 	bh_unlock_sock(sk);
2245 	if (skb)
2246 		tipc_node_xmit_skb(sock_net(sk), skb, peer_node, tsk->portid);
2247 exit:
2248 	sock_put(sk);
2249 }
2250 
2251 static int tipc_sk_publish(struct tipc_sock *tsk, uint scope,
2252 			   struct tipc_name_seq const *seq)
2253 {
2254 	struct net *net = sock_net(&tsk->sk);
2255 	struct publication *publ;
2256 	u32 key;
2257 
2258 	if (tsk->connected)
2259 		return -EINVAL;
2260 	key = tsk->portid + tsk->pub_count + 1;
2261 	if (key == tsk->portid)
2262 		return -EADDRINUSE;
2263 
2264 	publ = tipc_nametbl_publish(net, seq->type, seq->lower, seq->upper,
2265 				    scope, tsk->portid, key);
2266 	if (unlikely(!publ))
2267 		return -EINVAL;
2268 
2269 	list_add(&publ->pport_list, &tsk->publications);
2270 	tsk->pub_count++;
2271 	tsk->published = 1;
2272 	return 0;
2273 }
2274 
2275 static int tipc_sk_withdraw(struct tipc_sock *tsk, uint scope,
2276 			    struct tipc_name_seq const *seq)
2277 {
2278 	struct net *net = sock_net(&tsk->sk);
2279 	struct publication *publ;
2280 	struct publication *safe;
2281 	int rc = -EINVAL;
2282 
2283 	list_for_each_entry_safe(publ, safe, &tsk->publications, pport_list) {
2284 		if (seq) {
2285 			if (publ->scope != scope)
2286 				continue;
2287 			if (publ->type != seq->type)
2288 				continue;
2289 			if (publ->lower != seq->lower)
2290 				continue;
2291 			if (publ->upper != seq->upper)
2292 				break;
2293 			tipc_nametbl_withdraw(net, publ->type, publ->lower,
2294 					      publ->ref, publ->key);
2295 			rc = 0;
2296 			break;
2297 		}
2298 		tipc_nametbl_withdraw(net, publ->type, publ->lower,
2299 				      publ->ref, publ->key);
2300 		rc = 0;
2301 	}
2302 	if (list_empty(&tsk->publications))
2303 		tsk->published = 0;
2304 	return rc;
2305 }
2306 
2307 /* tipc_sk_reinit: set non-zero address in all existing sockets
2308  *                 when we go from standalone to network mode.
2309  */
2310 void tipc_sk_reinit(struct net *net)
2311 {
2312 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2313 	const struct bucket_table *tbl;
2314 	struct rhash_head *pos;
2315 	struct tipc_sock *tsk;
2316 	struct tipc_msg *msg;
2317 	int i;
2318 
2319 	rcu_read_lock();
2320 	tbl = rht_dereference_rcu((&tn->sk_rht)->tbl, &tn->sk_rht);
2321 	for (i = 0; i < tbl->size; i++) {
2322 		rht_for_each_entry_rcu(tsk, pos, tbl, i, node) {
2323 			spin_lock_bh(&tsk->sk.sk_lock.slock);
2324 			msg = &tsk->phdr;
2325 			msg_set_prevnode(msg, tn->own_addr);
2326 			msg_set_orignode(msg, tn->own_addr);
2327 			spin_unlock_bh(&tsk->sk.sk_lock.slock);
2328 		}
2329 	}
2330 	rcu_read_unlock();
2331 }
2332 
2333 static struct tipc_sock *tipc_sk_lookup(struct net *net, u32 portid)
2334 {
2335 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2336 	struct tipc_sock *tsk;
2337 
2338 	rcu_read_lock();
2339 	tsk = rhashtable_lookup_fast(&tn->sk_rht, &portid, tsk_rht_params);
2340 	if (tsk)
2341 		sock_hold(&tsk->sk);
2342 	rcu_read_unlock();
2343 
2344 	return tsk;
2345 }
2346 
2347 static int tipc_sk_insert(struct tipc_sock *tsk)
2348 {
2349 	struct sock *sk = &tsk->sk;
2350 	struct net *net = sock_net(sk);
2351 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2352 	u32 remaining = (TIPC_MAX_PORT - TIPC_MIN_PORT) + 1;
2353 	u32 portid = prandom_u32() % remaining + TIPC_MIN_PORT;
2354 
2355 	while (remaining--) {
2356 		portid++;
2357 		if ((portid < TIPC_MIN_PORT) || (portid > TIPC_MAX_PORT))
2358 			portid = TIPC_MIN_PORT;
2359 		tsk->portid = portid;
2360 		sock_hold(&tsk->sk);
2361 		if (!rhashtable_lookup_insert_fast(&tn->sk_rht, &tsk->node,
2362 						   tsk_rht_params))
2363 			return 0;
2364 		sock_put(&tsk->sk);
2365 	}
2366 
2367 	return -1;
2368 }
2369 
2370 static void tipc_sk_remove(struct tipc_sock *tsk)
2371 {
2372 	struct sock *sk = &tsk->sk;
2373 	struct tipc_net *tn = net_generic(sock_net(sk), tipc_net_id);
2374 
2375 	if (!rhashtable_remove_fast(&tn->sk_rht, &tsk->node, tsk_rht_params)) {
2376 		WARN_ON(atomic_read(&sk->sk_refcnt) == 1);
2377 		__sock_put(sk);
2378 	}
2379 }
2380 
2381 static const struct rhashtable_params tsk_rht_params = {
2382 	.nelem_hint = 192,
2383 	.head_offset = offsetof(struct tipc_sock, node),
2384 	.key_offset = offsetof(struct tipc_sock, portid),
2385 	.key_len = sizeof(u32), /* portid */
2386 	.max_size = 1048576,
2387 	.min_size = 256,
2388 	.automatic_shrinking = true,
2389 };
2390 
2391 int tipc_sk_rht_init(struct net *net)
2392 {
2393 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2394 
2395 	return rhashtable_init(&tn->sk_rht, &tsk_rht_params);
2396 }
2397 
2398 void tipc_sk_rht_destroy(struct net *net)
2399 {
2400 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2401 
2402 	/* Wait for socket readers to complete */
2403 	synchronize_net();
2404 
2405 	rhashtable_destroy(&tn->sk_rht);
2406 }
2407 
2408 /**
2409  * tipc_setsockopt - set socket option
2410  * @sock: socket structure
2411  * @lvl: option level
2412  * @opt: option identifier
2413  * @ov: pointer to new option value
2414  * @ol: length of option value
2415  *
2416  * For stream sockets only, accepts and ignores all IPPROTO_TCP options
2417  * (to ease compatibility).
2418  *
2419  * Returns 0 on success, errno otherwise
2420  */
2421 static int tipc_setsockopt(struct socket *sock, int lvl, int opt,
2422 			   char __user *ov, unsigned int ol)
2423 {
2424 	struct sock *sk = sock->sk;
2425 	struct tipc_sock *tsk = tipc_sk(sk);
2426 	u32 value;
2427 	int res;
2428 
2429 	if ((lvl == IPPROTO_TCP) && (sock->type == SOCK_STREAM))
2430 		return 0;
2431 	if (lvl != SOL_TIPC)
2432 		return -ENOPROTOOPT;
2433 	if (ol < sizeof(value))
2434 		return -EINVAL;
2435 	res = get_user(value, (u32 __user *)ov);
2436 	if (res)
2437 		return res;
2438 
2439 	lock_sock(sk);
2440 
2441 	switch (opt) {
2442 	case TIPC_IMPORTANCE:
2443 		res = tsk_set_importance(tsk, value);
2444 		break;
2445 	case TIPC_SRC_DROPPABLE:
2446 		if (sock->type != SOCK_STREAM)
2447 			tsk_set_unreliable(tsk, value);
2448 		else
2449 			res = -ENOPROTOOPT;
2450 		break;
2451 	case TIPC_DEST_DROPPABLE:
2452 		tsk_set_unreturnable(tsk, value);
2453 		break;
2454 	case TIPC_CONN_TIMEOUT:
2455 		tipc_sk(sk)->conn_timeout = value;
2456 		/* no need to set "res", since already 0 at this point */
2457 		break;
2458 	default:
2459 		res = -EINVAL;
2460 	}
2461 
2462 	release_sock(sk);
2463 
2464 	return res;
2465 }
2466 
2467 /**
2468  * tipc_getsockopt - get socket option
2469  * @sock: socket structure
2470  * @lvl: option level
2471  * @opt: option identifier
2472  * @ov: receptacle for option value
2473  * @ol: receptacle for length of option value
2474  *
2475  * For stream sockets only, returns 0 length result for all IPPROTO_TCP options
2476  * (to ease compatibility).
2477  *
2478  * Returns 0 on success, errno otherwise
2479  */
2480 static int tipc_getsockopt(struct socket *sock, int lvl, int opt,
2481 			   char __user *ov, int __user *ol)
2482 {
2483 	struct sock *sk = sock->sk;
2484 	struct tipc_sock *tsk = tipc_sk(sk);
2485 	int len;
2486 	u32 value;
2487 	int res;
2488 
2489 	if ((lvl == IPPROTO_TCP) && (sock->type == SOCK_STREAM))
2490 		return put_user(0, ol);
2491 	if (lvl != SOL_TIPC)
2492 		return -ENOPROTOOPT;
2493 	res = get_user(len, ol);
2494 	if (res)
2495 		return res;
2496 
2497 	lock_sock(sk);
2498 
2499 	switch (opt) {
2500 	case TIPC_IMPORTANCE:
2501 		value = tsk_importance(tsk);
2502 		break;
2503 	case TIPC_SRC_DROPPABLE:
2504 		value = tsk_unreliable(tsk);
2505 		break;
2506 	case TIPC_DEST_DROPPABLE:
2507 		value = tsk_unreturnable(tsk);
2508 		break;
2509 	case TIPC_CONN_TIMEOUT:
2510 		value = tsk->conn_timeout;
2511 		/* no need to set "res", since already 0 at this point */
2512 		break;
2513 	case TIPC_NODE_RECVQ_DEPTH:
2514 		value = 0; /* was tipc_queue_size, now obsolete */
2515 		break;
2516 	case TIPC_SOCK_RECVQ_DEPTH:
2517 		value = skb_queue_len(&sk->sk_receive_queue);
2518 		break;
2519 	default:
2520 		res = -EINVAL;
2521 	}
2522 
2523 	release_sock(sk);
2524 
2525 	if (res)
2526 		return res;	/* "get" failed */
2527 
2528 	if (len < sizeof(value))
2529 		return -EINVAL;
2530 
2531 	if (copy_to_user(ov, &value, sizeof(value)))
2532 		return -EFAULT;
2533 
2534 	return put_user(sizeof(value), ol);
2535 }
2536 
2537 static int tipc_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
2538 {
2539 	struct sock *sk = sock->sk;
2540 	struct tipc_sioc_ln_req lnr;
2541 	void __user *argp = (void __user *)arg;
2542 
2543 	switch (cmd) {
2544 	case SIOCGETLINKNAME:
2545 		if (copy_from_user(&lnr, argp, sizeof(lnr)))
2546 			return -EFAULT;
2547 		if (!tipc_node_get_linkname(sock_net(sk),
2548 					    lnr.bearer_id & 0xffff, lnr.peer,
2549 					    lnr.linkname, TIPC_MAX_LINK_NAME)) {
2550 			if (copy_to_user(argp, &lnr, sizeof(lnr)))
2551 				return -EFAULT;
2552 			return 0;
2553 		}
2554 		return -EADDRNOTAVAIL;
2555 	default:
2556 		return -ENOIOCTLCMD;
2557 	}
2558 }
2559 
2560 /* Protocol switches for the various types of TIPC sockets */
2561 
2562 static const struct proto_ops msg_ops = {
2563 	.owner		= THIS_MODULE,
2564 	.family		= AF_TIPC,
2565 	.release	= tipc_release,
2566 	.bind		= tipc_bind,
2567 	.connect	= tipc_connect,
2568 	.socketpair	= sock_no_socketpair,
2569 	.accept		= sock_no_accept,
2570 	.getname	= tipc_getname,
2571 	.poll		= tipc_poll,
2572 	.ioctl		= tipc_ioctl,
2573 	.listen		= sock_no_listen,
2574 	.shutdown	= tipc_shutdown,
2575 	.setsockopt	= tipc_setsockopt,
2576 	.getsockopt	= tipc_getsockopt,
2577 	.sendmsg	= tipc_sendmsg,
2578 	.recvmsg	= tipc_recvmsg,
2579 	.mmap		= sock_no_mmap,
2580 	.sendpage	= sock_no_sendpage
2581 };
2582 
2583 static const struct proto_ops packet_ops = {
2584 	.owner		= THIS_MODULE,
2585 	.family		= AF_TIPC,
2586 	.release	= tipc_release,
2587 	.bind		= tipc_bind,
2588 	.connect	= tipc_connect,
2589 	.socketpair	= sock_no_socketpair,
2590 	.accept		= tipc_accept,
2591 	.getname	= tipc_getname,
2592 	.poll		= tipc_poll,
2593 	.ioctl		= tipc_ioctl,
2594 	.listen		= tipc_listen,
2595 	.shutdown	= tipc_shutdown,
2596 	.setsockopt	= tipc_setsockopt,
2597 	.getsockopt	= tipc_getsockopt,
2598 	.sendmsg	= tipc_send_packet,
2599 	.recvmsg	= tipc_recvmsg,
2600 	.mmap		= sock_no_mmap,
2601 	.sendpage	= sock_no_sendpage
2602 };
2603 
2604 static const struct proto_ops stream_ops = {
2605 	.owner		= THIS_MODULE,
2606 	.family		= AF_TIPC,
2607 	.release	= tipc_release,
2608 	.bind		= tipc_bind,
2609 	.connect	= tipc_connect,
2610 	.socketpair	= sock_no_socketpair,
2611 	.accept		= tipc_accept,
2612 	.getname	= tipc_getname,
2613 	.poll		= tipc_poll,
2614 	.ioctl		= tipc_ioctl,
2615 	.listen		= tipc_listen,
2616 	.shutdown	= tipc_shutdown,
2617 	.setsockopt	= tipc_setsockopt,
2618 	.getsockopt	= tipc_getsockopt,
2619 	.sendmsg	= tipc_send_stream,
2620 	.recvmsg	= tipc_recv_stream,
2621 	.mmap		= sock_no_mmap,
2622 	.sendpage	= sock_no_sendpage
2623 };
2624 
2625 static const struct net_proto_family tipc_family_ops = {
2626 	.owner		= THIS_MODULE,
2627 	.family		= AF_TIPC,
2628 	.create		= tipc_sk_create
2629 };
2630 
2631 static struct proto tipc_proto = {
2632 	.name		= "TIPC",
2633 	.owner		= THIS_MODULE,
2634 	.obj_size	= sizeof(struct tipc_sock),
2635 	.sysctl_rmem	= sysctl_tipc_rmem
2636 };
2637 
2638 /**
2639  * tipc_socket_init - initialize TIPC socket interface
2640  *
2641  * Returns 0 on success, errno otherwise
2642  */
2643 int tipc_socket_init(void)
2644 {
2645 	int res;
2646 
2647 	res = proto_register(&tipc_proto, 1);
2648 	if (res) {
2649 		pr_err("Failed to register TIPC protocol type\n");
2650 		goto out;
2651 	}
2652 
2653 	res = sock_register(&tipc_family_ops);
2654 	if (res) {
2655 		pr_err("Failed to register TIPC socket type\n");
2656 		proto_unregister(&tipc_proto);
2657 		goto out;
2658 	}
2659  out:
2660 	return res;
2661 }
2662 
2663 /**
2664  * tipc_socket_stop - stop TIPC socket interface
2665  */
2666 void tipc_socket_stop(void)
2667 {
2668 	sock_unregister(tipc_family_ops.family);
2669 	proto_unregister(&tipc_proto);
2670 }
2671 
2672 /* Caller should hold socket lock for the passed tipc socket. */
2673 static int __tipc_nl_add_sk_con(struct sk_buff *skb, struct tipc_sock *tsk)
2674 {
2675 	u32 peer_node;
2676 	u32 peer_port;
2677 	struct nlattr *nest;
2678 
2679 	peer_node = tsk_peer_node(tsk);
2680 	peer_port = tsk_peer_port(tsk);
2681 
2682 	nest = nla_nest_start(skb, TIPC_NLA_SOCK_CON);
2683 
2684 	if (nla_put_u32(skb, TIPC_NLA_CON_NODE, peer_node))
2685 		goto msg_full;
2686 	if (nla_put_u32(skb, TIPC_NLA_CON_SOCK, peer_port))
2687 		goto msg_full;
2688 
2689 	if (tsk->conn_type != 0) {
2690 		if (nla_put_flag(skb, TIPC_NLA_CON_FLAG))
2691 			goto msg_full;
2692 		if (nla_put_u32(skb, TIPC_NLA_CON_TYPE, tsk->conn_type))
2693 			goto msg_full;
2694 		if (nla_put_u32(skb, TIPC_NLA_CON_INST, tsk->conn_instance))
2695 			goto msg_full;
2696 	}
2697 	nla_nest_end(skb, nest);
2698 
2699 	return 0;
2700 
2701 msg_full:
2702 	nla_nest_cancel(skb, nest);
2703 
2704 	return -EMSGSIZE;
2705 }
2706 
2707 /* Caller should hold socket lock for the passed tipc socket. */
2708 static int __tipc_nl_add_sk(struct sk_buff *skb, struct netlink_callback *cb,
2709 			    struct tipc_sock *tsk)
2710 {
2711 	int err;
2712 	void *hdr;
2713 	struct nlattr *attrs;
2714 	struct net *net = sock_net(skb->sk);
2715 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2716 
2717 	hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
2718 			  &tipc_genl_family, NLM_F_MULTI, TIPC_NL_SOCK_GET);
2719 	if (!hdr)
2720 		goto msg_cancel;
2721 
2722 	attrs = nla_nest_start(skb, TIPC_NLA_SOCK);
2723 	if (!attrs)
2724 		goto genlmsg_cancel;
2725 	if (nla_put_u32(skb, TIPC_NLA_SOCK_REF, tsk->portid))
2726 		goto attr_msg_cancel;
2727 	if (nla_put_u32(skb, TIPC_NLA_SOCK_ADDR, tn->own_addr))
2728 		goto attr_msg_cancel;
2729 
2730 	if (tsk->connected) {
2731 		err = __tipc_nl_add_sk_con(skb, tsk);
2732 		if (err)
2733 			goto attr_msg_cancel;
2734 	} else if (!list_empty(&tsk->publications)) {
2735 		if (nla_put_flag(skb, TIPC_NLA_SOCK_HAS_PUBL))
2736 			goto attr_msg_cancel;
2737 	}
2738 	nla_nest_end(skb, attrs);
2739 	genlmsg_end(skb, hdr);
2740 
2741 	return 0;
2742 
2743 attr_msg_cancel:
2744 	nla_nest_cancel(skb, attrs);
2745 genlmsg_cancel:
2746 	genlmsg_cancel(skb, hdr);
2747 msg_cancel:
2748 	return -EMSGSIZE;
2749 }
2750 
2751 int tipc_nl_sk_dump(struct sk_buff *skb, struct netlink_callback *cb)
2752 {
2753 	int err;
2754 	struct tipc_sock *tsk;
2755 	const struct bucket_table *tbl;
2756 	struct rhash_head *pos;
2757 	struct net *net = sock_net(skb->sk);
2758 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2759 	u32 tbl_id = cb->args[0];
2760 	u32 prev_portid = cb->args[1];
2761 
2762 	rcu_read_lock();
2763 	tbl = rht_dereference_rcu((&tn->sk_rht)->tbl, &tn->sk_rht);
2764 	for (; tbl_id < tbl->size; tbl_id++) {
2765 		rht_for_each_entry_rcu(tsk, pos, tbl, tbl_id, node) {
2766 			spin_lock_bh(&tsk->sk.sk_lock.slock);
2767 			if (prev_portid && prev_portid != tsk->portid) {
2768 				spin_unlock_bh(&tsk->sk.sk_lock.slock);
2769 				continue;
2770 			}
2771 
2772 			err = __tipc_nl_add_sk(skb, cb, tsk);
2773 			if (err) {
2774 				prev_portid = tsk->portid;
2775 				spin_unlock_bh(&tsk->sk.sk_lock.slock);
2776 				goto out;
2777 			}
2778 			prev_portid = 0;
2779 			spin_unlock_bh(&tsk->sk.sk_lock.slock);
2780 		}
2781 	}
2782 out:
2783 	rcu_read_unlock();
2784 	cb->args[0] = tbl_id;
2785 	cb->args[1] = prev_portid;
2786 
2787 	return skb->len;
2788 }
2789 
2790 /* Caller should hold socket lock for the passed tipc socket. */
2791 static int __tipc_nl_add_sk_publ(struct sk_buff *skb,
2792 				 struct netlink_callback *cb,
2793 				 struct publication *publ)
2794 {
2795 	void *hdr;
2796 	struct nlattr *attrs;
2797 
2798 	hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
2799 			  &tipc_genl_family, NLM_F_MULTI, TIPC_NL_PUBL_GET);
2800 	if (!hdr)
2801 		goto msg_cancel;
2802 
2803 	attrs = nla_nest_start(skb, TIPC_NLA_PUBL);
2804 	if (!attrs)
2805 		goto genlmsg_cancel;
2806 
2807 	if (nla_put_u32(skb, TIPC_NLA_PUBL_KEY, publ->key))
2808 		goto attr_msg_cancel;
2809 	if (nla_put_u32(skb, TIPC_NLA_PUBL_TYPE, publ->type))
2810 		goto attr_msg_cancel;
2811 	if (nla_put_u32(skb, TIPC_NLA_PUBL_LOWER, publ->lower))
2812 		goto attr_msg_cancel;
2813 	if (nla_put_u32(skb, TIPC_NLA_PUBL_UPPER, publ->upper))
2814 		goto attr_msg_cancel;
2815 
2816 	nla_nest_end(skb, attrs);
2817 	genlmsg_end(skb, hdr);
2818 
2819 	return 0;
2820 
2821 attr_msg_cancel:
2822 	nla_nest_cancel(skb, attrs);
2823 genlmsg_cancel:
2824 	genlmsg_cancel(skb, hdr);
2825 msg_cancel:
2826 	return -EMSGSIZE;
2827 }
2828 
2829 /* Caller should hold socket lock for the passed tipc socket. */
2830 static int __tipc_nl_list_sk_publ(struct sk_buff *skb,
2831 				  struct netlink_callback *cb,
2832 				  struct tipc_sock *tsk, u32 *last_publ)
2833 {
2834 	int err;
2835 	struct publication *p;
2836 
2837 	if (*last_publ) {
2838 		list_for_each_entry(p, &tsk->publications, pport_list) {
2839 			if (p->key == *last_publ)
2840 				break;
2841 		}
2842 		if (p->key != *last_publ) {
2843 			/* We never set seq or call nl_dump_check_consistent()
2844 			 * this means that setting prev_seq here will cause the
2845 			 * consistence check to fail in the netlink callback
2846 			 * handler. Resulting in the last NLMSG_DONE message
2847 			 * having the NLM_F_DUMP_INTR flag set.
2848 			 */
2849 			cb->prev_seq = 1;
2850 			*last_publ = 0;
2851 			return -EPIPE;
2852 		}
2853 	} else {
2854 		p = list_first_entry(&tsk->publications, struct publication,
2855 				     pport_list);
2856 	}
2857 
2858 	list_for_each_entry_from(p, &tsk->publications, pport_list) {
2859 		err = __tipc_nl_add_sk_publ(skb, cb, p);
2860 		if (err) {
2861 			*last_publ = p->key;
2862 			return err;
2863 		}
2864 	}
2865 	*last_publ = 0;
2866 
2867 	return 0;
2868 }
2869 
2870 int tipc_nl_publ_dump(struct sk_buff *skb, struct netlink_callback *cb)
2871 {
2872 	int err;
2873 	u32 tsk_portid = cb->args[0];
2874 	u32 last_publ = cb->args[1];
2875 	u32 done = cb->args[2];
2876 	struct net *net = sock_net(skb->sk);
2877 	struct tipc_sock *tsk;
2878 
2879 	if (!tsk_portid) {
2880 		struct nlattr **attrs;
2881 		struct nlattr *sock[TIPC_NLA_SOCK_MAX + 1];
2882 
2883 		err = tipc_nlmsg_parse(cb->nlh, &attrs);
2884 		if (err)
2885 			return err;
2886 
2887 		if (!attrs[TIPC_NLA_SOCK])
2888 			return -EINVAL;
2889 
2890 		err = nla_parse_nested(sock, TIPC_NLA_SOCK_MAX,
2891 				       attrs[TIPC_NLA_SOCK],
2892 				       tipc_nl_sock_policy);
2893 		if (err)
2894 			return err;
2895 
2896 		if (!sock[TIPC_NLA_SOCK_REF])
2897 			return -EINVAL;
2898 
2899 		tsk_portid = nla_get_u32(sock[TIPC_NLA_SOCK_REF]);
2900 	}
2901 
2902 	if (done)
2903 		return 0;
2904 
2905 	tsk = tipc_sk_lookup(net, tsk_portid);
2906 	if (!tsk)
2907 		return -EINVAL;
2908 
2909 	lock_sock(&tsk->sk);
2910 	err = __tipc_nl_list_sk_publ(skb, cb, tsk, &last_publ);
2911 	if (!err)
2912 		done = 1;
2913 	release_sock(&tsk->sk);
2914 	sock_put(&tsk->sk);
2915 
2916 	cb->args[0] = tsk_portid;
2917 	cb->args[1] = last_publ;
2918 	cb->args[2] = done;
2919 
2920 	return skb->len;
2921 }
2922