xref: /openbmc/linux/net/tipc/socket.c (revision bf070bb0)
1 /*
2  * net/tipc/socket.c: TIPC socket API
3  *
4  * Copyright (c) 2001-2007, 2012-2017, 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 <linux/sched/signal.h>
39 
40 #include "core.h"
41 #include "name_table.h"
42 #include "node.h"
43 #include "link.h"
44 #include "name_distr.h"
45 #include "socket.h"
46 #include "bcast.h"
47 #include "netlink.h"
48 #include "group.h"
49 
50 #define CONN_TIMEOUT_DEFAULT	8000	/* default connect timeout = 8s */
51 #define CONN_PROBING_INTV	msecs_to_jiffies(3600000)  /* [ms] => 1 h */
52 #define TIPC_FWD_MSG		1
53 #define TIPC_MAX_PORT		0xffffffff
54 #define TIPC_MIN_PORT		1
55 #define TIPC_ACK_RATE		4       /* ACK at 1/4 of of rcv window size */
56 
57 enum {
58 	TIPC_LISTEN = TCP_LISTEN,
59 	TIPC_ESTABLISHED = TCP_ESTABLISHED,
60 	TIPC_OPEN = TCP_CLOSE,
61 	TIPC_DISCONNECTING = TCP_CLOSE_WAIT,
62 	TIPC_CONNECTING = TCP_SYN_SENT,
63 };
64 
65 struct sockaddr_pair {
66 	struct sockaddr_tipc sock;
67 	struct sockaddr_tipc member;
68 };
69 
70 /**
71  * struct tipc_sock - TIPC socket structure
72  * @sk: socket - interacts with 'port' and with user via the socket API
73  * @conn_type: TIPC type used when connection was established
74  * @conn_instance: TIPC instance used when connection was established
75  * @published: non-zero if port has one or more associated names
76  * @max_pkt: maximum packet size "hint" used when building messages sent by port
77  * @portid: unique port identity in TIPC socket hash table
78  * @phdr: preformatted message header used when sending messages
79  * #cong_links: list of congested links
80  * @publications: list of publications for port
81  * @blocking_link: address of the congested link we are currently sleeping on
82  * @pub_count: total # of publications port has made during its lifetime
83  * @probing_state:
84  * @conn_timeout: the time we can wait for an unresponded setup request
85  * @dupl_rcvcnt: number of bytes counted twice, in both backlog and rcv queue
86  * @cong_link_cnt: number of congested links
87  * @snt_unacked: # messages sent by socket, and not yet acked by peer
88  * @rcv_unacked: # messages read by user, but not yet acked back to peer
89  * @peer: 'connected' peer for dgram/rdm
90  * @node: hash table node
91  * @mc_method: cookie for use between socket and broadcast layer
92  * @rcu: rcu struct for tipc_sock
93  */
94 struct tipc_sock {
95 	struct sock sk;
96 	u32 conn_type;
97 	u32 conn_instance;
98 	int published;
99 	u32 max_pkt;
100 	u32 portid;
101 	struct tipc_msg phdr;
102 	struct list_head cong_links;
103 	struct list_head publications;
104 	u32 pub_count;
105 	uint conn_timeout;
106 	atomic_t dupl_rcvcnt;
107 	bool probe_unacked;
108 	u16 cong_link_cnt;
109 	u16 snt_unacked;
110 	u16 snd_win;
111 	u16 peer_caps;
112 	u16 rcv_unacked;
113 	u16 rcv_win;
114 	struct sockaddr_tipc peer;
115 	struct rhash_head node;
116 	struct tipc_mc_method mc_method;
117 	struct rcu_head rcu;
118 	struct tipc_group *group;
119 };
120 
121 static int tipc_sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
122 static void tipc_data_ready(struct sock *sk);
123 static void tipc_write_space(struct sock *sk);
124 static void tipc_sock_destruct(struct sock *sk);
125 static int tipc_release(struct socket *sock);
126 static int tipc_accept(struct socket *sock, struct socket *new_sock, int flags,
127 		       bool kern);
128 static void tipc_sk_timeout(struct timer_list *t);
129 static int tipc_sk_publish(struct tipc_sock *tsk, uint scope,
130 			   struct tipc_name_seq const *seq);
131 static int tipc_sk_withdraw(struct tipc_sock *tsk, uint scope,
132 			    struct tipc_name_seq const *seq);
133 static int tipc_sk_leave(struct tipc_sock *tsk);
134 static struct tipc_sock *tipc_sk_lookup(struct net *net, u32 portid);
135 static int tipc_sk_insert(struct tipc_sock *tsk);
136 static void tipc_sk_remove(struct tipc_sock *tsk);
137 static int __tipc_sendstream(struct socket *sock, struct msghdr *m, size_t dsz);
138 static int __tipc_sendmsg(struct socket *sock, struct msghdr *m, size_t dsz);
139 
140 static const struct proto_ops packet_ops;
141 static const struct proto_ops stream_ops;
142 static const struct proto_ops msg_ops;
143 static struct proto tipc_proto;
144 static const struct rhashtable_params tsk_rht_params;
145 
146 static u32 tsk_own_node(struct tipc_sock *tsk)
147 {
148 	return msg_prevnode(&tsk->phdr);
149 }
150 
151 static u32 tsk_peer_node(struct tipc_sock *tsk)
152 {
153 	return msg_destnode(&tsk->phdr);
154 }
155 
156 static u32 tsk_peer_port(struct tipc_sock *tsk)
157 {
158 	return msg_destport(&tsk->phdr);
159 }
160 
161 static  bool tsk_unreliable(struct tipc_sock *tsk)
162 {
163 	return msg_src_droppable(&tsk->phdr) != 0;
164 }
165 
166 static void tsk_set_unreliable(struct tipc_sock *tsk, bool unreliable)
167 {
168 	msg_set_src_droppable(&tsk->phdr, unreliable ? 1 : 0);
169 }
170 
171 static bool tsk_unreturnable(struct tipc_sock *tsk)
172 {
173 	return msg_dest_droppable(&tsk->phdr) != 0;
174 }
175 
176 static void tsk_set_unreturnable(struct tipc_sock *tsk, bool unreturnable)
177 {
178 	msg_set_dest_droppable(&tsk->phdr, unreturnable ? 1 : 0);
179 }
180 
181 static int tsk_importance(struct tipc_sock *tsk)
182 {
183 	return msg_importance(&tsk->phdr);
184 }
185 
186 static int tsk_set_importance(struct tipc_sock *tsk, int imp)
187 {
188 	if (imp > TIPC_CRITICAL_IMPORTANCE)
189 		return -EINVAL;
190 	msg_set_importance(&tsk->phdr, (u32)imp);
191 	return 0;
192 }
193 
194 static struct tipc_sock *tipc_sk(const struct sock *sk)
195 {
196 	return container_of(sk, struct tipc_sock, sk);
197 }
198 
199 static bool tsk_conn_cong(struct tipc_sock *tsk)
200 {
201 	return tsk->snt_unacked > tsk->snd_win;
202 }
203 
204 static u16 tsk_blocks(int len)
205 {
206 	return ((len / FLOWCTL_BLK_SZ) + 1);
207 }
208 
209 /* tsk_blocks(): translate a buffer size in bytes to number of
210  * advertisable blocks, taking into account the ratio truesize(len)/len
211  * We can trust that this ratio is always < 4 for len >= FLOWCTL_BLK_SZ
212  */
213 static u16 tsk_adv_blocks(int len)
214 {
215 	return len / FLOWCTL_BLK_SZ / 4;
216 }
217 
218 /* tsk_inc(): increment counter for sent or received data
219  * - If block based flow control is not supported by peer we
220  *   fall back to message based ditto, incrementing the counter
221  */
222 static u16 tsk_inc(struct tipc_sock *tsk, int msglen)
223 {
224 	if (likely(tsk->peer_caps & TIPC_BLOCK_FLOWCTL))
225 		return ((msglen / FLOWCTL_BLK_SZ) + 1);
226 	return 1;
227 }
228 
229 /**
230  * tsk_advance_rx_queue - discard first buffer in socket receive queue
231  *
232  * Caller must hold socket lock
233  */
234 static void tsk_advance_rx_queue(struct sock *sk)
235 {
236 	kfree_skb(__skb_dequeue(&sk->sk_receive_queue));
237 }
238 
239 /* tipc_sk_respond() : send response message back to sender
240  */
241 static void tipc_sk_respond(struct sock *sk, struct sk_buff *skb, int err)
242 {
243 	u32 selector;
244 	u32 dnode;
245 	u32 onode = tipc_own_addr(sock_net(sk));
246 
247 	if (!tipc_msg_reverse(onode, &skb, err))
248 		return;
249 
250 	dnode = msg_destnode(buf_msg(skb));
251 	selector = msg_origport(buf_msg(skb));
252 	tipc_node_xmit_skb(sock_net(sk), skb, dnode, selector);
253 }
254 
255 /**
256  * tsk_rej_rx_queue - reject all buffers in socket receive queue
257  *
258  * Caller must hold socket lock
259  */
260 static void tsk_rej_rx_queue(struct sock *sk)
261 {
262 	struct sk_buff *skb;
263 
264 	while ((skb = __skb_dequeue(&sk->sk_receive_queue)))
265 		tipc_sk_respond(sk, skb, TIPC_ERR_NO_PORT);
266 }
267 
268 static bool tipc_sk_connected(struct sock *sk)
269 {
270 	return sk->sk_state == TIPC_ESTABLISHED;
271 }
272 
273 /* tipc_sk_type_connectionless - check if the socket is datagram socket
274  * @sk: socket
275  *
276  * Returns true if connection less, false otherwise
277  */
278 static bool tipc_sk_type_connectionless(struct sock *sk)
279 {
280 	return sk->sk_type == SOCK_RDM || sk->sk_type == SOCK_DGRAM;
281 }
282 
283 /* tsk_peer_msg - verify if message was sent by connected port's peer
284  *
285  * Handles cases where the node's network address has changed from
286  * the default of <0.0.0> to its configured setting.
287  */
288 static bool tsk_peer_msg(struct tipc_sock *tsk, struct tipc_msg *msg)
289 {
290 	struct sock *sk = &tsk->sk;
291 	struct tipc_net *tn = net_generic(sock_net(sk), tipc_net_id);
292 	u32 peer_port = tsk_peer_port(tsk);
293 	u32 orig_node;
294 	u32 peer_node;
295 
296 	if (unlikely(!tipc_sk_connected(sk)))
297 		return false;
298 
299 	if (unlikely(msg_origport(msg) != peer_port))
300 		return false;
301 
302 	orig_node = msg_orignode(msg);
303 	peer_node = tsk_peer_node(tsk);
304 
305 	if (likely(orig_node == peer_node))
306 		return true;
307 
308 	if (!orig_node && (peer_node == tn->own_addr))
309 		return true;
310 
311 	if (!peer_node && (orig_node == tn->own_addr))
312 		return true;
313 
314 	return false;
315 }
316 
317 /* tipc_set_sk_state - set the sk_state of the socket
318  * @sk: socket
319  *
320  * Caller must hold socket lock
321  *
322  * Returns 0 on success, errno otherwise
323  */
324 static int tipc_set_sk_state(struct sock *sk, int state)
325 {
326 	int oldsk_state = sk->sk_state;
327 	int res = -EINVAL;
328 
329 	switch (state) {
330 	case TIPC_OPEN:
331 		res = 0;
332 		break;
333 	case TIPC_LISTEN:
334 	case TIPC_CONNECTING:
335 		if (oldsk_state == TIPC_OPEN)
336 			res = 0;
337 		break;
338 	case TIPC_ESTABLISHED:
339 		if (oldsk_state == TIPC_CONNECTING ||
340 		    oldsk_state == TIPC_OPEN)
341 			res = 0;
342 		break;
343 	case TIPC_DISCONNECTING:
344 		if (oldsk_state == TIPC_CONNECTING ||
345 		    oldsk_state == TIPC_ESTABLISHED)
346 			res = 0;
347 		break;
348 	}
349 
350 	if (!res)
351 		sk->sk_state = state;
352 
353 	return res;
354 }
355 
356 static int tipc_sk_sock_err(struct socket *sock, long *timeout)
357 {
358 	struct sock *sk = sock->sk;
359 	int err = sock_error(sk);
360 	int typ = sock->type;
361 
362 	if (err)
363 		return err;
364 	if (typ == SOCK_STREAM || typ == SOCK_SEQPACKET) {
365 		if (sk->sk_state == TIPC_DISCONNECTING)
366 			return -EPIPE;
367 		else if (!tipc_sk_connected(sk))
368 			return -ENOTCONN;
369 	}
370 	if (!*timeout)
371 		return -EAGAIN;
372 	if (signal_pending(current))
373 		return sock_intr_errno(*timeout);
374 
375 	return 0;
376 }
377 
378 #define tipc_wait_for_cond(sock_, timeo_, condition_)			       \
379 ({                                                                             \
380 	struct sock *sk_;						       \
381 	int rc_;							       \
382 									       \
383 	while ((rc_ = !(condition_))) {					       \
384 		DEFINE_WAIT_FUNC(wait_, woken_wake_function);	               \
385 		sk_ = (sock_)->sk;					       \
386 		rc_ = tipc_sk_sock_err((sock_), timeo_);		       \
387 		if (rc_)						       \
388 			break;						       \
389 		prepare_to_wait(sk_sleep(sk_), &wait_, TASK_INTERRUPTIBLE);    \
390 		release_sock(sk_);					       \
391 		*(timeo_) = wait_woken(&wait_, TASK_INTERRUPTIBLE, *(timeo_)); \
392 		sched_annotate_sleep();				               \
393 		lock_sock(sk_);						       \
394 		remove_wait_queue(sk_sleep(sk_), &wait_);		       \
395 	}								       \
396 	rc_;								       \
397 })
398 
399 /**
400  * tipc_sk_create - create a TIPC socket
401  * @net: network namespace (must be default network)
402  * @sock: pre-allocated socket structure
403  * @protocol: protocol indicator (must be 0)
404  * @kern: caused by kernel or by userspace?
405  *
406  * This routine creates additional data structures used by the TIPC socket,
407  * initializes them, and links them together.
408  *
409  * Returns 0 on success, errno otherwise
410  */
411 static int tipc_sk_create(struct net *net, struct socket *sock,
412 			  int protocol, int kern)
413 {
414 	struct tipc_net *tn;
415 	const struct proto_ops *ops;
416 	struct sock *sk;
417 	struct tipc_sock *tsk;
418 	struct tipc_msg *msg;
419 
420 	/* Validate arguments */
421 	if (unlikely(protocol != 0))
422 		return -EPROTONOSUPPORT;
423 
424 	switch (sock->type) {
425 	case SOCK_STREAM:
426 		ops = &stream_ops;
427 		break;
428 	case SOCK_SEQPACKET:
429 		ops = &packet_ops;
430 		break;
431 	case SOCK_DGRAM:
432 	case SOCK_RDM:
433 		ops = &msg_ops;
434 		break;
435 	default:
436 		return -EPROTOTYPE;
437 	}
438 
439 	/* Allocate socket's protocol area */
440 	sk = sk_alloc(net, AF_TIPC, GFP_KERNEL, &tipc_proto, kern);
441 	if (sk == NULL)
442 		return -ENOMEM;
443 
444 	tsk = tipc_sk(sk);
445 	tsk->max_pkt = MAX_PKT_DEFAULT;
446 	INIT_LIST_HEAD(&tsk->publications);
447 	INIT_LIST_HEAD(&tsk->cong_links);
448 	msg = &tsk->phdr;
449 	tn = net_generic(sock_net(sk), tipc_net_id);
450 
451 	/* Finish initializing socket data structures */
452 	sock->ops = ops;
453 	sock_init_data(sock, sk);
454 	tipc_set_sk_state(sk, TIPC_OPEN);
455 	if (tipc_sk_insert(tsk)) {
456 		pr_warn("Socket create failed; port number exhausted\n");
457 		return -EINVAL;
458 	}
459 
460 	/* Ensure tsk is visible before we read own_addr. */
461 	smp_mb();
462 
463 	tipc_msg_init(tn->own_addr, msg, TIPC_LOW_IMPORTANCE, TIPC_NAMED_MSG,
464 		      NAMED_H_SIZE, 0);
465 
466 	msg_set_origport(msg, tsk->portid);
467 	timer_setup(&sk->sk_timer, tipc_sk_timeout, 0);
468 	sk->sk_shutdown = 0;
469 	sk->sk_backlog_rcv = tipc_sk_backlog_rcv;
470 	sk->sk_rcvbuf = sysctl_tipc_rmem[1];
471 	sk->sk_data_ready = tipc_data_ready;
472 	sk->sk_write_space = tipc_write_space;
473 	sk->sk_destruct = tipc_sock_destruct;
474 	tsk->conn_timeout = CONN_TIMEOUT_DEFAULT;
475 	atomic_set(&tsk->dupl_rcvcnt, 0);
476 
477 	/* Start out with safe limits until we receive an advertised window */
478 	tsk->snd_win = tsk_adv_blocks(RCVBUF_MIN);
479 	tsk->rcv_win = tsk->snd_win;
480 
481 	if (tipc_sk_type_connectionless(sk)) {
482 		tsk_set_unreturnable(tsk, true);
483 		if (sock->type == SOCK_DGRAM)
484 			tsk_set_unreliable(tsk, true);
485 	}
486 
487 	return 0;
488 }
489 
490 static void tipc_sk_callback(struct rcu_head *head)
491 {
492 	struct tipc_sock *tsk = container_of(head, struct tipc_sock, rcu);
493 
494 	sock_put(&tsk->sk);
495 }
496 
497 /* Caller should hold socket lock for the socket. */
498 static void __tipc_shutdown(struct socket *sock, int error)
499 {
500 	struct sock *sk = sock->sk;
501 	struct tipc_sock *tsk = tipc_sk(sk);
502 	struct net *net = sock_net(sk);
503 	long timeout = CONN_TIMEOUT_DEFAULT;
504 	u32 dnode = tsk_peer_node(tsk);
505 	struct sk_buff *skb;
506 
507 	/* Avoid that hi-prio shutdown msgs bypass msgs in link wakeup queue */
508 	tipc_wait_for_cond(sock, &timeout, (!tsk->cong_link_cnt &&
509 					    !tsk_conn_cong(tsk)));
510 
511 	/* Reject all unreceived messages, except on an active connection
512 	 * (which disconnects locally & sends a 'FIN+' to peer).
513 	 */
514 	while ((skb = __skb_dequeue(&sk->sk_receive_queue)) != NULL) {
515 		if (TIPC_SKB_CB(skb)->bytes_read) {
516 			kfree_skb(skb);
517 			continue;
518 		}
519 		if (!tipc_sk_type_connectionless(sk) &&
520 		    sk->sk_state != TIPC_DISCONNECTING) {
521 			tipc_set_sk_state(sk, TIPC_DISCONNECTING);
522 			tipc_node_remove_conn(net, dnode, tsk->portid);
523 		}
524 		tipc_sk_respond(sk, skb, error);
525 	}
526 
527 	if (tipc_sk_type_connectionless(sk))
528 		return;
529 
530 	if (sk->sk_state != TIPC_DISCONNECTING) {
531 		skb = tipc_msg_create(TIPC_CRITICAL_IMPORTANCE,
532 				      TIPC_CONN_MSG, SHORT_H_SIZE, 0, dnode,
533 				      tsk_own_node(tsk), tsk_peer_port(tsk),
534 				      tsk->portid, error);
535 		if (skb)
536 			tipc_node_xmit_skb(net, skb, dnode, tsk->portid);
537 		tipc_node_remove_conn(net, dnode, tsk->portid);
538 		tipc_set_sk_state(sk, TIPC_DISCONNECTING);
539 	}
540 }
541 
542 /**
543  * tipc_release - destroy a TIPC socket
544  * @sock: socket to destroy
545  *
546  * This routine cleans up any messages that are still queued on the socket.
547  * For DGRAM and RDM socket types, all queued messages are rejected.
548  * For SEQPACKET and STREAM socket types, the first message is rejected
549  * and any others are discarded.  (If the first message on a STREAM socket
550  * is partially-read, it is discarded and the next one is rejected instead.)
551  *
552  * NOTE: Rejected messages are not necessarily returned to the sender!  They
553  * are returned or discarded according to the "destination droppable" setting
554  * specified for the message by the sender.
555  *
556  * Returns 0 on success, errno otherwise
557  */
558 static int tipc_release(struct socket *sock)
559 {
560 	struct sock *sk = sock->sk;
561 	struct tipc_sock *tsk;
562 
563 	/*
564 	 * Exit if socket isn't fully initialized (occurs when a failed accept()
565 	 * releases a pre-allocated child socket that was never used)
566 	 */
567 	if (sk == NULL)
568 		return 0;
569 
570 	tsk = tipc_sk(sk);
571 	lock_sock(sk);
572 
573 	__tipc_shutdown(sock, TIPC_ERR_NO_PORT);
574 	sk->sk_shutdown = SHUTDOWN_MASK;
575 	tipc_sk_leave(tsk);
576 	tipc_sk_withdraw(tsk, 0, NULL);
577 	sk_stop_timer(sk, &sk->sk_timer);
578 	tipc_sk_remove(tsk);
579 
580 	/* Reject any messages that accumulated in backlog queue */
581 	release_sock(sk);
582 	tipc_dest_list_purge(&tsk->cong_links);
583 	tsk->cong_link_cnt = 0;
584 	call_rcu(&tsk->rcu, tipc_sk_callback);
585 	sock->sk = NULL;
586 
587 	return 0;
588 }
589 
590 /**
591  * tipc_bind - associate or disassocate TIPC name(s) with a socket
592  * @sock: socket structure
593  * @uaddr: socket address describing name(s) and desired operation
594  * @uaddr_len: size of socket address data structure
595  *
596  * Name and name sequence binding is indicated using a positive scope value;
597  * a negative scope value unbinds the specified name.  Specifying no name
598  * (i.e. a socket address length of 0) unbinds all names from the socket.
599  *
600  * Returns 0 on success, errno otherwise
601  *
602  * NOTE: This routine doesn't need to take the socket lock since it doesn't
603  *       access any non-constant socket information.
604  */
605 static int tipc_bind(struct socket *sock, struct sockaddr *uaddr,
606 		     int uaddr_len)
607 {
608 	struct sock *sk = sock->sk;
609 	struct sockaddr_tipc *addr = (struct sockaddr_tipc *)uaddr;
610 	struct tipc_sock *tsk = tipc_sk(sk);
611 	int res = -EINVAL;
612 
613 	lock_sock(sk);
614 	if (unlikely(!uaddr_len)) {
615 		res = tipc_sk_withdraw(tsk, 0, NULL);
616 		goto exit;
617 	}
618 	if (tsk->group) {
619 		res = -EACCES;
620 		goto exit;
621 	}
622 	if (uaddr_len < sizeof(struct sockaddr_tipc)) {
623 		res = -EINVAL;
624 		goto exit;
625 	}
626 	if (addr->family != AF_TIPC) {
627 		res = -EAFNOSUPPORT;
628 		goto exit;
629 	}
630 
631 	if (addr->addrtype == TIPC_ADDR_NAME)
632 		addr->addr.nameseq.upper = addr->addr.nameseq.lower;
633 	else if (addr->addrtype != TIPC_ADDR_NAMESEQ) {
634 		res = -EAFNOSUPPORT;
635 		goto exit;
636 	}
637 
638 	if ((addr->addr.nameseq.type < TIPC_RESERVED_TYPES) &&
639 	    (addr->addr.nameseq.type != TIPC_TOP_SRV) &&
640 	    (addr->addr.nameseq.type != TIPC_CFG_SRV)) {
641 		res = -EACCES;
642 		goto exit;
643 	}
644 
645 	res = (addr->scope > 0) ?
646 		tipc_sk_publish(tsk, addr->scope, &addr->addr.nameseq) :
647 		tipc_sk_withdraw(tsk, -addr->scope, &addr->addr.nameseq);
648 exit:
649 	release_sock(sk);
650 	return res;
651 }
652 
653 /**
654  * tipc_getname - get port ID of socket or peer socket
655  * @sock: socket structure
656  * @uaddr: area for returned socket address
657  * @uaddr_len: area for returned length of socket address
658  * @peer: 0 = own ID, 1 = current peer ID, 2 = current/former peer ID
659  *
660  * Returns 0 on success, errno otherwise
661  *
662  * NOTE: This routine doesn't need to take the socket lock since it only
663  *       accesses socket information that is unchanging (or which changes in
664  *       a completely predictable manner).
665  */
666 static int tipc_getname(struct socket *sock, struct sockaddr *uaddr,
667 			int *uaddr_len, int peer)
668 {
669 	struct sockaddr_tipc *addr = (struct sockaddr_tipc *)uaddr;
670 	struct sock *sk = sock->sk;
671 	struct tipc_sock *tsk = tipc_sk(sk);
672 	struct tipc_net *tn = net_generic(sock_net(sock->sk), tipc_net_id);
673 
674 	memset(addr, 0, sizeof(*addr));
675 	if (peer) {
676 		if ((!tipc_sk_connected(sk)) &&
677 		    ((peer != 2) || (sk->sk_state != TIPC_DISCONNECTING)))
678 			return -ENOTCONN;
679 		addr->addr.id.ref = tsk_peer_port(tsk);
680 		addr->addr.id.node = tsk_peer_node(tsk);
681 	} else {
682 		addr->addr.id.ref = tsk->portid;
683 		addr->addr.id.node = tn->own_addr;
684 	}
685 
686 	*uaddr_len = sizeof(*addr);
687 	addr->addrtype = TIPC_ADDR_ID;
688 	addr->family = AF_TIPC;
689 	addr->scope = 0;
690 	addr->addr.name.domain = 0;
691 
692 	return 0;
693 }
694 
695 /**
696  * tipc_poll - read and possibly block on pollmask
697  * @file: file structure associated with the socket
698  * @sock: socket for which to calculate the poll bits
699  * @wait: ???
700  *
701  * Returns pollmask value
702  *
703  * COMMENTARY:
704  * It appears that the usual socket locking mechanisms are not useful here
705  * since the pollmask info is potentially out-of-date the moment this routine
706  * exits.  TCP and other protocols seem to rely on higher level poll routines
707  * to handle any preventable race conditions, so TIPC will do the same ...
708  *
709  * IMPORTANT: The fact that a read or write operation is indicated does NOT
710  * imply that the operation will succeed, merely that it should be performed
711  * and will not block.
712  */
713 static unsigned int tipc_poll(struct file *file, struct socket *sock,
714 			      poll_table *wait)
715 {
716 	struct sock *sk = sock->sk;
717 	struct tipc_sock *tsk = tipc_sk(sk);
718 	struct tipc_group *grp = tsk->group;
719 	u32 revents = 0;
720 
721 	sock_poll_wait(file, sk_sleep(sk), wait);
722 
723 	if (sk->sk_shutdown & RCV_SHUTDOWN)
724 		revents |= POLLRDHUP | POLLIN | POLLRDNORM;
725 	if (sk->sk_shutdown == SHUTDOWN_MASK)
726 		revents |= POLLHUP;
727 
728 	switch (sk->sk_state) {
729 	case TIPC_ESTABLISHED:
730 		if (!tsk->cong_link_cnt && !tsk_conn_cong(tsk))
731 			revents |= POLLOUT;
732 		/* fall thru' */
733 	case TIPC_LISTEN:
734 	case TIPC_CONNECTING:
735 		if (!skb_queue_empty(&sk->sk_receive_queue))
736 			revents |= POLLIN | POLLRDNORM;
737 		break;
738 	case TIPC_OPEN:
739 		if (!grp || tipc_group_size(grp))
740 			if (!tsk->cong_link_cnt)
741 				revents |= POLLOUT;
742 		if (!tipc_sk_type_connectionless(sk))
743 			break;
744 		if (skb_queue_empty(&sk->sk_receive_queue))
745 			break;
746 		revents |= POLLIN | POLLRDNORM;
747 		break;
748 	case TIPC_DISCONNECTING:
749 		revents = POLLIN | POLLRDNORM | POLLHUP;
750 		break;
751 	}
752 	return revents;
753 }
754 
755 /**
756  * tipc_sendmcast - send multicast message
757  * @sock: socket structure
758  * @seq: destination address
759  * @msg: message to send
760  * @dlen: length of data to send
761  * @timeout: timeout to wait for wakeup
762  *
763  * Called from function tipc_sendmsg(), which has done all sanity checks
764  * Returns the number of bytes sent on success, or errno
765  */
766 static int tipc_sendmcast(struct  socket *sock, struct tipc_name_seq *seq,
767 			  struct msghdr *msg, size_t dlen, long timeout)
768 {
769 	struct sock *sk = sock->sk;
770 	struct tipc_sock *tsk = tipc_sk(sk);
771 	struct tipc_msg *hdr = &tsk->phdr;
772 	struct net *net = sock_net(sk);
773 	int mtu = tipc_bcast_get_mtu(net);
774 	struct tipc_mc_method *method = &tsk->mc_method;
775 	u32 domain = addr_domain(net, TIPC_CLUSTER_SCOPE);
776 	struct sk_buff_head pkts;
777 	struct tipc_nlist dsts;
778 	int rc;
779 
780 	if (tsk->group)
781 		return -EACCES;
782 
783 	/* Block or return if any destination link is congested */
784 	rc = tipc_wait_for_cond(sock, &timeout, !tsk->cong_link_cnt);
785 	if (unlikely(rc))
786 		return rc;
787 
788 	/* Lookup destination nodes */
789 	tipc_nlist_init(&dsts, tipc_own_addr(net));
790 	tipc_nametbl_lookup_dst_nodes(net, seq->type, seq->lower,
791 				      seq->upper, domain, &dsts);
792 	if (!dsts.local && !dsts.remote)
793 		return -EHOSTUNREACH;
794 
795 	/* Build message header */
796 	msg_set_type(hdr, TIPC_MCAST_MSG);
797 	msg_set_hdr_sz(hdr, MCAST_H_SIZE);
798 	msg_set_lookup_scope(hdr, TIPC_CLUSTER_SCOPE);
799 	msg_set_destport(hdr, 0);
800 	msg_set_destnode(hdr, 0);
801 	msg_set_nametype(hdr, seq->type);
802 	msg_set_namelower(hdr, seq->lower);
803 	msg_set_nameupper(hdr, seq->upper);
804 
805 	/* Build message as chain of buffers */
806 	skb_queue_head_init(&pkts);
807 	rc = tipc_msg_build(hdr, msg, 0, dlen, mtu, &pkts);
808 
809 	/* Send message if build was successful */
810 	if (unlikely(rc == dlen))
811 		rc = tipc_mcast_xmit(net, &pkts, method, &dsts,
812 				     &tsk->cong_link_cnt);
813 
814 	tipc_nlist_purge(&dsts);
815 
816 	return rc ? rc : dlen;
817 }
818 
819 /**
820  * tipc_send_group_msg - send a message to a member in the group
821  * @net: network namespace
822  * @m: message to send
823  * @mb: group member
824  * @dnode: destination node
825  * @dport: destination port
826  * @dlen: total length of message data
827  */
828 static int tipc_send_group_msg(struct net *net, struct tipc_sock *tsk,
829 			       struct msghdr *m, struct tipc_member *mb,
830 			       u32 dnode, u32 dport, int dlen)
831 {
832 	u16 bc_snd_nxt = tipc_group_bc_snd_nxt(tsk->group);
833 	struct tipc_mc_method *method = &tsk->mc_method;
834 	int blks = tsk_blocks(GROUP_H_SIZE + dlen);
835 	struct tipc_msg *hdr = &tsk->phdr;
836 	struct sk_buff_head pkts;
837 	int mtu, rc;
838 
839 	/* Complete message header */
840 	msg_set_type(hdr, TIPC_GRP_UCAST_MSG);
841 	msg_set_hdr_sz(hdr, GROUP_H_SIZE);
842 	msg_set_destport(hdr, dport);
843 	msg_set_destnode(hdr, dnode);
844 	msg_set_grp_bc_seqno(hdr, bc_snd_nxt);
845 
846 	/* Build message as chain of buffers */
847 	skb_queue_head_init(&pkts);
848 	mtu = tipc_node_get_mtu(net, dnode, tsk->portid);
849 	rc = tipc_msg_build(hdr, m, 0, dlen, mtu, &pkts);
850 	if (unlikely(rc != dlen))
851 		return rc;
852 
853 	/* Send message */
854 	rc = tipc_node_xmit(net, &pkts, dnode, tsk->portid);
855 	if (unlikely(rc == -ELINKCONG)) {
856 		tipc_dest_push(&tsk->cong_links, dnode, 0);
857 		tsk->cong_link_cnt++;
858 	}
859 
860 	/* Update send window */
861 	tipc_group_update_member(mb, blks);
862 
863 	/* A broadcast sent within next EXPIRE period must follow same path */
864 	method->rcast = true;
865 	method->mandatory = true;
866 	return dlen;
867 }
868 
869 /**
870  * tipc_send_group_unicast - send message to a member in the group
871  * @sock: socket structure
872  * @m: message to send
873  * @dlen: total length of message data
874  * @timeout: timeout to wait for wakeup
875  *
876  * Called from function tipc_sendmsg(), which has done all sanity checks
877  * Returns the number of bytes sent on success, or errno
878  */
879 static int tipc_send_group_unicast(struct socket *sock, struct msghdr *m,
880 				   int dlen, long timeout)
881 {
882 	struct sock *sk = sock->sk;
883 	DECLARE_SOCKADDR(struct sockaddr_tipc *, dest, m->msg_name);
884 	int blks = tsk_blocks(GROUP_H_SIZE + dlen);
885 	struct tipc_sock *tsk = tipc_sk(sk);
886 	struct tipc_group *grp = tsk->group;
887 	struct net *net = sock_net(sk);
888 	struct tipc_member *mb = NULL;
889 	u32 node, port;
890 	int rc;
891 
892 	node = dest->addr.id.node;
893 	port = dest->addr.id.ref;
894 	if (!port && !node)
895 		return -EHOSTUNREACH;
896 
897 	/* Block or return if destination link or member is congested */
898 	rc = tipc_wait_for_cond(sock, &timeout,
899 				!tipc_dest_find(&tsk->cong_links, node, 0) &&
900 				!tipc_group_cong(grp, node, port, blks, &mb));
901 	if (unlikely(rc))
902 		return rc;
903 
904 	if (unlikely(!mb))
905 		return -EHOSTUNREACH;
906 
907 	rc = tipc_send_group_msg(net, tsk, m, mb, node, port, dlen);
908 
909 	return rc ? rc : dlen;
910 }
911 
912 /**
913  * tipc_send_group_anycast - send message to any member with given identity
914  * @sock: socket structure
915  * @m: message to send
916  * @dlen: total length of message data
917  * @timeout: timeout to wait for wakeup
918  *
919  * Called from function tipc_sendmsg(), which has done all sanity checks
920  * Returns the number of bytes sent on success, or errno
921  */
922 static int tipc_send_group_anycast(struct socket *sock, struct msghdr *m,
923 				   int dlen, long timeout)
924 {
925 	DECLARE_SOCKADDR(struct sockaddr_tipc *, dest, m->msg_name);
926 	struct sock *sk = sock->sk;
927 	struct tipc_sock *tsk = tipc_sk(sk);
928 	struct list_head *cong_links = &tsk->cong_links;
929 	int blks = tsk_blocks(GROUP_H_SIZE + dlen);
930 	struct tipc_group *grp = tsk->group;
931 	struct tipc_member *first = NULL;
932 	struct tipc_member *mbr = NULL;
933 	struct net *net = sock_net(sk);
934 	u32 node, port, exclude;
935 	u32 type, inst, domain;
936 	struct list_head dsts;
937 	int lookups = 0;
938 	int dstcnt, rc;
939 	bool cong;
940 
941 	INIT_LIST_HEAD(&dsts);
942 
943 	type = dest->addr.name.name.type;
944 	inst = dest->addr.name.name.instance;
945 	domain = addr_domain(net, dest->scope);
946 	exclude = tipc_group_exclude(grp);
947 
948 	while (++lookups < 4) {
949 		first = NULL;
950 
951 		/* Look for a non-congested destination member, if any */
952 		while (1) {
953 			if (!tipc_nametbl_lookup(net, type, inst, domain, &dsts,
954 						 &dstcnt, exclude, false))
955 				return -EHOSTUNREACH;
956 			tipc_dest_pop(&dsts, &node, &port);
957 			cong = tipc_group_cong(grp, node, port, blks, &mbr);
958 			if (!cong)
959 				break;
960 			if (mbr == first)
961 				break;
962 			if (!first)
963 				first = mbr;
964 		}
965 
966 		/* Start over if destination was not in member list */
967 		if (unlikely(!mbr))
968 			continue;
969 
970 		if (likely(!cong && !tipc_dest_find(cong_links, node, 0)))
971 			break;
972 
973 		/* Block or return if destination link or member is congested */
974 		rc = tipc_wait_for_cond(sock, &timeout,
975 					!tipc_dest_find(cong_links, node, 0) &&
976 					!tipc_group_cong(grp, node, port,
977 							 blks, &mbr));
978 		if (unlikely(rc))
979 			return rc;
980 
981 		/* Send, unless destination disappeared while waiting */
982 		if (likely(mbr))
983 			break;
984 	}
985 
986 	if (unlikely(lookups >= 4))
987 		return -EHOSTUNREACH;
988 
989 	rc = tipc_send_group_msg(net, tsk, m, mbr, node, port, dlen);
990 
991 	return rc ? rc : dlen;
992 }
993 
994 /**
995  * tipc_send_group_bcast - send message to all members in communication group
996  * @sk: socket structure
997  * @m: message to send
998  * @dlen: total length of message data
999  * @timeout: timeout to wait for wakeup
1000  *
1001  * Called from function tipc_sendmsg(), which has done all sanity checks
1002  * Returns the number of bytes sent on success, or errno
1003  */
1004 static int tipc_send_group_bcast(struct socket *sock, struct msghdr *m,
1005 				 int dlen, long timeout)
1006 {
1007 	DECLARE_SOCKADDR(struct sockaddr_tipc *, dest, m->msg_name);
1008 	struct sock *sk = sock->sk;
1009 	struct net *net = sock_net(sk);
1010 	struct tipc_sock *tsk = tipc_sk(sk);
1011 	struct tipc_group *grp = tsk->group;
1012 	struct tipc_nlist *dsts = tipc_group_dests(grp);
1013 	struct tipc_mc_method *method = &tsk->mc_method;
1014 	bool ack = method->mandatory && method->rcast;
1015 	int blks = tsk_blocks(MCAST_H_SIZE + dlen);
1016 	struct tipc_msg *hdr = &tsk->phdr;
1017 	int mtu = tipc_bcast_get_mtu(net);
1018 	struct sk_buff_head pkts;
1019 	int rc = -EHOSTUNREACH;
1020 
1021 	if (!dsts->local && !dsts->remote)
1022 		return -EHOSTUNREACH;
1023 
1024 	/* Block or return if any destination link or member is congested */
1025 	rc = tipc_wait_for_cond(sock, &timeout,	!tsk->cong_link_cnt &&
1026 				!tipc_group_bc_cong(grp, blks));
1027 	if (unlikely(rc))
1028 		return rc;
1029 
1030 	/* Complete message header */
1031 	if (dest) {
1032 		msg_set_type(hdr, TIPC_GRP_MCAST_MSG);
1033 		msg_set_nameinst(hdr, dest->addr.name.name.instance);
1034 	} else {
1035 		msg_set_type(hdr, TIPC_GRP_BCAST_MSG);
1036 		msg_set_nameinst(hdr, 0);
1037 	}
1038 	msg_set_hdr_sz(hdr, GROUP_H_SIZE);
1039 	msg_set_destport(hdr, 0);
1040 	msg_set_destnode(hdr, 0);
1041 	msg_set_grp_bc_seqno(hdr, tipc_group_bc_snd_nxt(grp));
1042 
1043 	/* Avoid getting stuck with repeated forced replicasts */
1044 	msg_set_grp_bc_ack_req(hdr, ack);
1045 
1046 	/* Build message as chain of buffers */
1047 	skb_queue_head_init(&pkts);
1048 	rc = tipc_msg_build(hdr, m, 0, dlen, mtu, &pkts);
1049 	if (unlikely(rc != dlen))
1050 		return rc;
1051 
1052 	/* Send message */
1053 	rc = tipc_mcast_xmit(net, &pkts, method, dsts, &tsk->cong_link_cnt);
1054 	if (unlikely(rc))
1055 		return rc;
1056 
1057 	/* Update broadcast sequence number and send windows */
1058 	tipc_group_update_bc_members(tsk->group, blks, ack);
1059 
1060 	/* Broadcast link is now free to choose method for next broadcast */
1061 	method->mandatory = false;
1062 	method->expires = jiffies;
1063 
1064 	return dlen;
1065 }
1066 
1067 /**
1068  * tipc_send_group_mcast - send message to all members with given identity
1069  * @sock: socket structure
1070  * @m: message to send
1071  * @dlen: total length of message data
1072  * @timeout: timeout to wait for wakeup
1073  *
1074  * Called from function tipc_sendmsg(), which has done all sanity checks
1075  * Returns the number of bytes sent on success, or errno
1076  */
1077 static int tipc_send_group_mcast(struct socket *sock, struct msghdr *m,
1078 				 int dlen, long timeout)
1079 {
1080 	struct sock *sk = sock->sk;
1081 	DECLARE_SOCKADDR(struct sockaddr_tipc *, dest, m->msg_name);
1082 	struct tipc_name_seq *seq = &dest->addr.nameseq;
1083 	struct tipc_sock *tsk = tipc_sk(sk);
1084 	struct tipc_group *grp = tsk->group;
1085 	struct net *net = sock_net(sk);
1086 	u32 domain, exclude, dstcnt;
1087 	struct list_head dsts;
1088 
1089 	INIT_LIST_HEAD(&dsts);
1090 
1091 	if (seq->lower != seq->upper)
1092 		return -ENOTSUPP;
1093 
1094 	domain = addr_domain(net, dest->scope);
1095 	exclude = tipc_group_exclude(grp);
1096 	if (!tipc_nametbl_lookup(net, seq->type, seq->lower, domain,
1097 				 &dsts, &dstcnt, exclude, true))
1098 		return -EHOSTUNREACH;
1099 
1100 	if (dstcnt == 1) {
1101 		tipc_dest_pop(&dsts, &dest->addr.id.node, &dest->addr.id.ref);
1102 		return tipc_send_group_unicast(sock, m, dlen, timeout);
1103 	}
1104 
1105 	tipc_dest_list_purge(&dsts);
1106 	return tipc_send_group_bcast(sock, m, dlen, timeout);
1107 }
1108 
1109 /**
1110  * tipc_sk_mcast_rcv - Deliver multicast messages to all destination sockets
1111  * @arrvq: queue with arriving messages, to be cloned after destination lookup
1112  * @inputq: queue with cloned messages, delivered to socket after dest lookup
1113  *
1114  * Multi-threaded: parallel calls with reference to same queues may occur
1115  */
1116 void tipc_sk_mcast_rcv(struct net *net, struct sk_buff_head *arrvq,
1117 		       struct sk_buff_head *inputq)
1118 {
1119 	u32 scope = TIPC_CLUSTER_SCOPE;
1120 	u32 self = tipc_own_addr(net);
1121 	struct sk_buff *skb, *_skb;
1122 	u32 lower = 0, upper = ~0;
1123 	struct sk_buff_head tmpq;
1124 	u32 portid, oport, onode;
1125 	struct list_head dports;
1126 	struct tipc_msg *msg;
1127 	int user, mtyp, hsz;
1128 
1129 	__skb_queue_head_init(&tmpq);
1130 	INIT_LIST_HEAD(&dports);
1131 
1132 	skb = tipc_skb_peek(arrvq, &inputq->lock);
1133 	for (; skb; skb = tipc_skb_peek(arrvq, &inputq->lock)) {
1134 		msg = buf_msg(skb);
1135 		user = msg_user(msg);
1136 		mtyp = msg_type(msg);
1137 		if (mtyp == TIPC_GRP_UCAST_MSG || user == GROUP_PROTOCOL) {
1138 			spin_lock_bh(&inputq->lock);
1139 			if (skb_peek(arrvq) == skb) {
1140 				__skb_dequeue(arrvq);
1141 				__skb_queue_tail(inputq, skb);
1142 			}
1143 			refcount_dec(&skb->users);
1144 			spin_unlock_bh(&inputq->lock);
1145 			continue;
1146 		}
1147 		hsz = skb_headroom(skb) + msg_hdr_sz(msg);
1148 		oport = msg_origport(msg);
1149 		onode = msg_orignode(msg);
1150 		if (onode == self)
1151 			scope = TIPC_NODE_SCOPE;
1152 
1153 		/* Create destination port list and message clones: */
1154 		if (!msg_in_group(msg)) {
1155 			lower = msg_namelower(msg);
1156 			upper = msg_nameupper(msg);
1157 		}
1158 		tipc_nametbl_mc_translate(net, msg_nametype(msg), lower, upper,
1159 					  scope, &dports);
1160 		while (tipc_dest_pop(&dports, NULL, &portid)) {
1161 			_skb = __pskb_copy(skb, hsz, GFP_ATOMIC);
1162 			if (_skb) {
1163 				msg_set_destport(buf_msg(_skb), portid);
1164 				__skb_queue_tail(&tmpq, _skb);
1165 				continue;
1166 			}
1167 			pr_warn("Failed to clone mcast rcv buffer\n");
1168 		}
1169 		/* Append to inputq if not already done by other thread */
1170 		spin_lock_bh(&inputq->lock);
1171 		if (skb_peek(arrvq) == skb) {
1172 			skb_queue_splice_tail_init(&tmpq, inputq);
1173 			kfree_skb(__skb_dequeue(arrvq));
1174 		}
1175 		spin_unlock_bh(&inputq->lock);
1176 		__skb_queue_purge(&tmpq);
1177 		kfree_skb(skb);
1178 	}
1179 	tipc_sk_rcv(net, inputq);
1180 }
1181 
1182 /**
1183  * tipc_sk_conn_proto_rcv - receive a connection mng protocol message
1184  * @tsk: receiving socket
1185  * @skb: pointer to message buffer.
1186  */
1187 static void tipc_sk_conn_proto_rcv(struct tipc_sock *tsk, struct sk_buff *skb,
1188 				   struct sk_buff_head *xmitq)
1189 {
1190 	struct tipc_msg *hdr = buf_msg(skb);
1191 	u32 onode = tsk_own_node(tsk);
1192 	struct sock *sk = &tsk->sk;
1193 	int mtyp = msg_type(hdr);
1194 	bool conn_cong;
1195 
1196 	/* Ignore if connection cannot be validated: */
1197 	if (!tsk_peer_msg(tsk, hdr))
1198 		goto exit;
1199 
1200 	if (unlikely(msg_errcode(hdr))) {
1201 		tipc_set_sk_state(sk, TIPC_DISCONNECTING);
1202 		tipc_node_remove_conn(sock_net(sk), tsk_peer_node(tsk),
1203 				      tsk_peer_port(tsk));
1204 		sk->sk_state_change(sk);
1205 		goto exit;
1206 	}
1207 
1208 	tsk->probe_unacked = false;
1209 
1210 	if (mtyp == CONN_PROBE) {
1211 		msg_set_type(hdr, CONN_PROBE_REPLY);
1212 		if (tipc_msg_reverse(onode, &skb, TIPC_OK))
1213 			__skb_queue_tail(xmitq, skb);
1214 		return;
1215 	} else if (mtyp == CONN_ACK) {
1216 		conn_cong = tsk_conn_cong(tsk);
1217 		tsk->snt_unacked -= msg_conn_ack(hdr);
1218 		if (tsk->peer_caps & TIPC_BLOCK_FLOWCTL)
1219 			tsk->snd_win = msg_adv_win(hdr);
1220 		if (conn_cong)
1221 			sk->sk_write_space(sk);
1222 	} else if (mtyp != CONN_PROBE_REPLY) {
1223 		pr_warn("Received unknown CONN_PROTO msg\n");
1224 	}
1225 exit:
1226 	kfree_skb(skb);
1227 }
1228 
1229 /**
1230  * tipc_sendmsg - send message in connectionless manner
1231  * @sock: socket structure
1232  * @m: message to send
1233  * @dsz: amount of user data to be sent
1234  *
1235  * Message must have an destination specified explicitly.
1236  * Used for SOCK_RDM and SOCK_DGRAM messages,
1237  * and for 'SYN' messages on SOCK_SEQPACKET and SOCK_STREAM connections.
1238  * (Note: 'SYN+' is prohibited on SOCK_STREAM.)
1239  *
1240  * Returns the number of bytes sent on success, or errno otherwise
1241  */
1242 static int tipc_sendmsg(struct socket *sock,
1243 			struct msghdr *m, size_t dsz)
1244 {
1245 	struct sock *sk = sock->sk;
1246 	int ret;
1247 
1248 	lock_sock(sk);
1249 	ret = __tipc_sendmsg(sock, m, dsz);
1250 	release_sock(sk);
1251 
1252 	return ret;
1253 }
1254 
1255 static int __tipc_sendmsg(struct socket *sock, struct msghdr *m, size_t dlen)
1256 {
1257 	struct sock *sk = sock->sk;
1258 	struct net *net = sock_net(sk);
1259 	struct tipc_sock *tsk = tipc_sk(sk);
1260 	DECLARE_SOCKADDR(struct sockaddr_tipc *, dest, m->msg_name);
1261 	long timeout = sock_sndtimeo(sk, m->msg_flags & MSG_DONTWAIT);
1262 	struct list_head *clinks = &tsk->cong_links;
1263 	bool syn = !tipc_sk_type_connectionless(sk);
1264 	struct tipc_group *grp = tsk->group;
1265 	struct tipc_msg *hdr = &tsk->phdr;
1266 	struct tipc_name_seq *seq;
1267 	struct sk_buff_head pkts;
1268 	u32 type, inst, domain;
1269 	u32 dnode, dport;
1270 	int mtu, rc;
1271 
1272 	if (unlikely(dlen > TIPC_MAX_USER_MSG_SIZE))
1273 		return -EMSGSIZE;
1274 
1275 	if (likely(dest)) {
1276 		if (unlikely(m->msg_namelen < sizeof(*dest)))
1277 			return -EINVAL;
1278 		if (unlikely(dest->family != AF_TIPC))
1279 			return -EINVAL;
1280 	}
1281 
1282 	if (grp) {
1283 		if (!dest)
1284 			return tipc_send_group_bcast(sock, m, dlen, timeout);
1285 		if (dest->addrtype == TIPC_ADDR_NAME)
1286 			return tipc_send_group_anycast(sock, m, dlen, timeout);
1287 		if (dest->addrtype == TIPC_ADDR_ID)
1288 			return tipc_send_group_unicast(sock, m, dlen, timeout);
1289 		if (dest->addrtype == TIPC_ADDR_MCAST)
1290 			return tipc_send_group_mcast(sock, m, dlen, timeout);
1291 		return -EINVAL;
1292 	}
1293 
1294 	if (unlikely(!dest)) {
1295 		dest = &tsk->peer;
1296 		if (!syn || dest->family != AF_TIPC)
1297 			return -EDESTADDRREQ;
1298 	}
1299 
1300 	if (unlikely(syn)) {
1301 		if (sk->sk_state == TIPC_LISTEN)
1302 			return -EPIPE;
1303 		if (sk->sk_state != TIPC_OPEN)
1304 			return -EISCONN;
1305 		if (tsk->published)
1306 			return -EOPNOTSUPP;
1307 		if (dest->addrtype == TIPC_ADDR_NAME) {
1308 			tsk->conn_type = dest->addr.name.name.type;
1309 			tsk->conn_instance = dest->addr.name.name.instance;
1310 		}
1311 	}
1312 
1313 	seq = &dest->addr.nameseq;
1314 	if (dest->addrtype == TIPC_ADDR_MCAST)
1315 		return tipc_sendmcast(sock, seq, m, dlen, timeout);
1316 
1317 	if (dest->addrtype == TIPC_ADDR_NAME) {
1318 		type = dest->addr.name.name.type;
1319 		inst = dest->addr.name.name.instance;
1320 		domain = dest->addr.name.domain;
1321 		dnode = domain;
1322 		msg_set_type(hdr, TIPC_NAMED_MSG);
1323 		msg_set_hdr_sz(hdr, NAMED_H_SIZE);
1324 		msg_set_nametype(hdr, type);
1325 		msg_set_nameinst(hdr, inst);
1326 		msg_set_lookup_scope(hdr, tipc_addr_scope(domain));
1327 		dport = tipc_nametbl_translate(net, type, inst, &dnode);
1328 		msg_set_destnode(hdr, dnode);
1329 		msg_set_destport(hdr, dport);
1330 		if (unlikely(!dport && !dnode))
1331 			return -EHOSTUNREACH;
1332 	} else if (dest->addrtype == TIPC_ADDR_ID) {
1333 		dnode = dest->addr.id.node;
1334 		msg_set_type(hdr, TIPC_DIRECT_MSG);
1335 		msg_set_lookup_scope(hdr, 0);
1336 		msg_set_destnode(hdr, dnode);
1337 		msg_set_destport(hdr, dest->addr.id.ref);
1338 		msg_set_hdr_sz(hdr, BASIC_H_SIZE);
1339 	}
1340 
1341 	/* Block or return if destination link is congested */
1342 	rc = tipc_wait_for_cond(sock, &timeout,
1343 				!tipc_dest_find(clinks, dnode, 0));
1344 	if (unlikely(rc))
1345 		return rc;
1346 
1347 	skb_queue_head_init(&pkts);
1348 	mtu = tipc_node_get_mtu(net, dnode, tsk->portid);
1349 	rc = tipc_msg_build(hdr, m, 0, dlen, mtu, &pkts);
1350 	if (unlikely(rc != dlen))
1351 		return rc;
1352 
1353 	rc = tipc_node_xmit(net, &pkts, dnode, tsk->portid);
1354 	if (unlikely(rc == -ELINKCONG)) {
1355 		tipc_dest_push(clinks, dnode, 0);
1356 		tsk->cong_link_cnt++;
1357 		rc = 0;
1358 	}
1359 
1360 	if (unlikely(syn && !rc))
1361 		tipc_set_sk_state(sk, TIPC_CONNECTING);
1362 
1363 	return rc ? rc : dlen;
1364 }
1365 
1366 /**
1367  * tipc_sendstream - send stream-oriented data
1368  * @sock: socket structure
1369  * @m: data to send
1370  * @dsz: total length of data to be transmitted
1371  *
1372  * Used for SOCK_STREAM data.
1373  *
1374  * Returns the number of bytes sent on success (or partial success),
1375  * or errno if no data sent
1376  */
1377 static int tipc_sendstream(struct socket *sock, struct msghdr *m, size_t dsz)
1378 {
1379 	struct sock *sk = sock->sk;
1380 	int ret;
1381 
1382 	lock_sock(sk);
1383 	ret = __tipc_sendstream(sock, m, dsz);
1384 	release_sock(sk);
1385 
1386 	return ret;
1387 }
1388 
1389 static int __tipc_sendstream(struct socket *sock, struct msghdr *m, size_t dlen)
1390 {
1391 	struct sock *sk = sock->sk;
1392 	DECLARE_SOCKADDR(struct sockaddr_tipc *, dest, m->msg_name);
1393 	long timeout = sock_sndtimeo(sk, m->msg_flags & MSG_DONTWAIT);
1394 	struct tipc_sock *tsk = tipc_sk(sk);
1395 	struct tipc_msg *hdr = &tsk->phdr;
1396 	struct net *net = sock_net(sk);
1397 	struct sk_buff_head pkts;
1398 	u32 dnode = tsk_peer_node(tsk);
1399 	int send, sent = 0;
1400 	int rc = 0;
1401 
1402 	skb_queue_head_init(&pkts);
1403 
1404 	if (unlikely(dlen > INT_MAX))
1405 		return -EMSGSIZE;
1406 
1407 	/* Handle implicit connection setup */
1408 	if (unlikely(dest)) {
1409 		rc = __tipc_sendmsg(sock, m, dlen);
1410 		if (dlen && (dlen == rc))
1411 			tsk->snt_unacked = tsk_inc(tsk, dlen + msg_hdr_sz(hdr));
1412 		return rc;
1413 	}
1414 
1415 	do {
1416 		rc = tipc_wait_for_cond(sock, &timeout,
1417 					(!tsk->cong_link_cnt &&
1418 					 !tsk_conn_cong(tsk) &&
1419 					 tipc_sk_connected(sk)));
1420 		if (unlikely(rc))
1421 			break;
1422 
1423 		send = min_t(size_t, dlen - sent, TIPC_MAX_USER_MSG_SIZE);
1424 		rc = tipc_msg_build(hdr, m, sent, send, tsk->max_pkt, &pkts);
1425 		if (unlikely(rc != send))
1426 			break;
1427 
1428 		rc = tipc_node_xmit(net, &pkts, dnode, tsk->portid);
1429 		if (unlikely(rc == -ELINKCONG)) {
1430 			tsk->cong_link_cnt = 1;
1431 			rc = 0;
1432 		}
1433 		if (likely(!rc)) {
1434 			tsk->snt_unacked += tsk_inc(tsk, send + MIN_H_SIZE);
1435 			sent += send;
1436 		}
1437 	} while (sent < dlen && !rc);
1438 
1439 	return sent ? sent : rc;
1440 }
1441 
1442 /**
1443  * tipc_send_packet - send a connection-oriented message
1444  * @sock: socket structure
1445  * @m: message to send
1446  * @dsz: length of data to be transmitted
1447  *
1448  * Used for SOCK_SEQPACKET messages.
1449  *
1450  * Returns the number of bytes sent on success, or errno otherwise
1451  */
1452 static int tipc_send_packet(struct socket *sock, struct msghdr *m, size_t dsz)
1453 {
1454 	if (dsz > TIPC_MAX_USER_MSG_SIZE)
1455 		return -EMSGSIZE;
1456 
1457 	return tipc_sendstream(sock, m, dsz);
1458 }
1459 
1460 /* tipc_sk_finish_conn - complete the setup of a connection
1461  */
1462 static void tipc_sk_finish_conn(struct tipc_sock *tsk, u32 peer_port,
1463 				u32 peer_node)
1464 {
1465 	struct sock *sk = &tsk->sk;
1466 	struct net *net = sock_net(sk);
1467 	struct tipc_msg *msg = &tsk->phdr;
1468 
1469 	msg_set_destnode(msg, peer_node);
1470 	msg_set_destport(msg, peer_port);
1471 	msg_set_type(msg, TIPC_CONN_MSG);
1472 	msg_set_lookup_scope(msg, 0);
1473 	msg_set_hdr_sz(msg, SHORT_H_SIZE);
1474 
1475 	sk_reset_timer(sk, &sk->sk_timer, jiffies + CONN_PROBING_INTV);
1476 	tipc_set_sk_state(sk, TIPC_ESTABLISHED);
1477 	tipc_node_add_conn(net, peer_node, tsk->portid, peer_port);
1478 	tsk->max_pkt = tipc_node_get_mtu(net, peer_node, tsk->portid);
1479 	tsk->peer_caps = tipc_node_get_capabilities(net, peer_node);
1480 	if (tsk->peer_caps & TIPC_BLOCK_FLOWCTL)
1481 		return;
1482 
1483 	/* Fall back to message based flow control */
1484 	tsk->rcv_win = FLOWCTL_MSG_WIN;
1485 	tsk->snd_win = FLOWCTL_MSG_WIN;
1486 }
1487 
1488 /**
1489  * tipc_sk_set_orig_addr - capture sender's address for received message
1490  * @m: descriptor for message info
1491  * @hdr: received message header
1492  *
1493  * Note: Address is not captured if not requested by receiver.
1494  */
1495 static void tipc_sk_set_orig_addr(struct msghdr *m, struct sk_buff *skb)
1496 {
1497 	DECLARE_SOCKADDR(struct sockaddr_pair *, srcaddr, m->msg_name);
1498 	struct tipc_msg *hdr = buf_msg(skb);
1499 
1500 	if (!srcaddr)
1501 		return;
1502 
1503 	srcaddr->sock.family = AF_TIPC;
1504 	srcaddr->sock.addrtype = TIPC_ADDR_ID;
1505 	srcaddr->sock.addr.id.ref = msg_origport(hdr);
1506 	srcaddr->sock.addr.id.node = msg_orignode(hdr);
1507 	srcaddr->sock.addr.name.domain = 0;
1508 	srcaddr->sock.scope = 0;
1509 	m->msg_namelen = sizeof(struct sockaddr_tipc);
1510 
1511 	if (!msg_in_group(hdr))
1512 		return;
1513 
1514 	/* Group message users may also want to know sending member's id */
1515 	srcaddr->member.family = AF_TIPC;
1516 	srcaddr->member.addrtype = TIPC_ADDR_NAME;
1517 	srcaddr->member.addr.name.name.type = msg_nametype(hdr);
1518 	srcaddr->member.addr.name.name.instance = TIPC_SKB_CB(skb)->orig_member;
1519 	srcaddr->member.addr.name.domain = 0;
1520 	m->msg_namelen = sizeof(*srcaddr);
1521 }
1522 
1523 /**
1524  * tipc_sk_anc_data_recv - optionally capture ancillary data for received message
1525  * @m: descriptor for message info
1526  * @msg: received message header
1527  * @tsk: TIPC port associated with message
1528  *
1529  * Note: Ancillary data is not captured if not requested by receiver.
1530  *
1531  * Returns 0 if successful, otherwise errno
1532  */
1533 static int tipc_sk_anc_data_recv(struct msghdr *m, struct tipc_msg *msg,
1534 				 struct tipc_sock *tsk)
1535 {
1536 	u32 anc_data[3];
1537 	u32 err;
1538 	u32 dest_type;
1539 	int has_name;
1540 	int res;
1541 
1542 	if (likely(m->msg_controllen == 0))
1543 		return 0;
1544 
1545 	/* Optionally capture errored message object(s) */
1546 	err = msg ? msg_errcode(msg) : 0;
1547 	if (unlikely(err)) {
1548 		anc_data[0] = err;
1549 		anc_data[1] = msg_data_sz(msg);
1550 		res = put_cmsg(m, SOL_TIPC, TIPC_ERRINFO, 8, anc_data);
1551 		if (res)
1552 			return res;
1553 		if (anc_data[1]) {
1554 			res = put_cmsg(m, SOL_TIPC, TIPC_RETDATA, anc_data[1],
1555 				       msg_data(msg));
1556 			if (res)
1557 				return res;
1558 		}
1559 	}
1560 
1561 	/* Optionally capture message destination object */
1562 	dest_type = msg ? msg_type(msg) : TIPC_DIRECT_MSG;
1563 	switch (dest_type) {
1564 	case TIPC_NAMED_MSG:
1565 		has_name = 1;
1566 		anc_data[0] = msg_nametype(msg);
1567 		anc_data[1] = msg_namelower(msg);
1568 		anc_data[2] = msg_namelower(msg);
1569 		break;
1570 	case TIPC_MCAST_MSG:
1571 		has_name = 1;
1572 		anc_data[0] = msg_nametype(msg);
1573 		anc_data[1] = msg_namelower(msg);
1574 		anc_data[2] = msg_nameupper(msg);
1575 		break;
1576 	case TIPC_CONN_MSG:
1577 		has_name = (tsk->conn_type != 0);
1578 		anc_data[0] = tsk->conn_type;
1579 		anc_data[1] = tsk->conn_instance;
1580 		anc_data[2] = tsk->conn_instance;
1581 		break;
1582 	default:
1583 		has_name = 0;
1584 	}
1585 	if (has_name) {
1586 		res = put_cmsg(m, SOL_TIPC, TIPC_DESTNAME, 12, anc_data);
1587 		if (res)
1588 			return res;
1589 	}
1590 
1591 	return 0;
1592 }
1593 
1594 static void tipc_sk_send_ack(struct tipc_sock *tsk)
1595 {
1596 	struct sock *sk = &tsk->sk;
1597 	struct net *net = sock_net(sk);
1598 	struct sk_buff *skb = NULL;
1599 	struct tipc_msg *msg;
1600 	u32 peer_port = tsk_peer_port(tsk);
1601 	u32 dnode = tsk_peer_node(tsk);
1602 
1603 	if (!tipc_sk_connected(sk))
1604 		return;
1605 	skb = tipc_msg_create(CONN_MANAGER, CONN_ACK, INT_H_SIZE, 0,
1606 			      dnode, tsk_own_node(tsk), peer_port,
1607 			      tsk->portid, TIPC_OK);
1608 	if (!skb)
1609 		return;
1610 	msg = buf_msg(skb);
1611 	msg_set_conn_ack(msg, tsk->rcv_unacked);
1612 	tsk->rcv_unacked = 0;
1613 
1614 	/* Adjust to and advertize the correct window limit */
1615 	if (tsk->peer_caps & TIPC_BLOCK_FLOWCTL) {
1616 		tsk->rcv_win = tsk_adv_blocks(tsk->sk.sk_rcvbuf);
1617 		msg_set_adv_win(msg, tsk->rcv_win);
1618 	}
1619 	tipc_node_xmit_skb(net, skb, dnode, msg_link_selector(msg));
1620 }
1621 
1622 static int tipc_wait_for_rcvmsg(struct socket *sock, long *timeop)
1623 {
1624 	struct sock *sk = sock->sk;
1625 	DEFINE_WAIT(wait);
1626 	long timeo = *timeop;
1627 	int err = sock_error(sk);
1628 
1629 	if (err)
1630 		return err;
1631 
1632 	for (;;) {
1633 		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1634 		if (timeo && skb_queue_empty(&sk->sk_receive_queue)) {
1635 			if (sk->sk_shutdown & RCV_SHUTDOWN) {
1636 				err = -ENOTCONN;
1637 				break;
1638 			}
1639 			release_sock(sk);
1640 			timeo = schedule_timeout(timeo);
1641 			lock_sock(sk);
1642 		}
1643 		err = 0;
1644 		if (!skb_queue_empty(&sk->sk_receive_queue))
1645 			break;
1646 		err = -EAGAIN;
1647 		if (!timeo)
1648 			break;
1649 		err = sock_intr_errno(timeo);
1650 		if (signal_pending(current))
1651 			break;
1652 
1653 		err = sock_error(sk);
1654 		if (err)
1655 			break;
1656 	}
1657 	finish_wait(sk_sleep(sk), &wait);
1658 	*timeop = timeo;
1659 	return err;
1660 }
1661 
1662 /**
1663  * tipc_recvmsg - receive packet-oriented message
1664  * @m: descriptor for message info
1665  * @buflen: length of user buffer area
1666  * @flags: receive flags
1667  *
1668  * Used for SOCK_DGRAM, SOCK_RDM, and SOCK_SEQPACKET messages.
1669  * If the complete message doesn't fit in user area, truncate it.
1670  *
1671  * Returns size of returned message data, errno otherwise
1672  */
1673 static int tipc_recvmsg(struct socket *sock, struct msghdr *m,
1674 			size_t buflen,	int flags)
1675 {
1676 	struct sock *sk = sock->sk;
1677 	bool connected = !tipc_sk_type_connectionless(sk);
1678 	struct tipc_sock *tsk = tipc_sk(sk);
1679 	int rc, err, hlen, dlen, copy;
1680 	struct sk_buff_head xmitq;
1681 	struct tipc_msg *hdr;
1682 	struct sk_buff *skb;
1683 	bool grp_evt;
1684 	long timeout;
1685 
1686 	/* Catch invalid receive requests */
1687 	if (unlikely(!buflen))
1688 		return -EINVAL;
1689 
1690 	lock_sock(sk);
1691 	if (unlikely(connected && sk->sk_state == TIPC_OPEN)) {
1692 		rc = -ENOTCONN;
1693 		goto exit;
1694 	}
1695 	timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
1696 
1697 	/* Step rcv queue to first msg with data or error; wait if necessary */
1698 	do {
1699 		rc = tipc_wait_for_rcvmsg(sock, &timeout);
1700 		if (unlikely(rc))
1701 			goto exit;
1702 		skb = skb_peek(&sk->sk_receive_queue);
1703 		hdr = buf_msg(skb);
1704 		dlen = msg_data_sz(hdr);
1705 		hlen = msg_hdr_sz(hdr);
1706 		err = msg_errcode(hdr);
1707 		grp_evt = msg_is_grp_evt(hdr);
1708 		if (likely(dlen || err))
1709 			break;
1710 		tsk_advance_rx_queue(sk);
1711 	} while (1);
1712 
1713 	/* Collect msg meta data, including error code and rejected data */
1714 	tipc_sk_set_orig_addr(m, skb);
1715 	rc = tipc_sk_anc_data_recv(m, hdr, tsk);
1716 	if (unlikely(rc))
1717 		goto exit;
1718 
1719 	/* Capture data if non-error msg, otherwise just set return value */
1720 	if (likely(!err)) {
1721 		copy = min_t(int, dlen, buflen);
1722 		if (unlikely(copy != dlen))
1723 			m->msg_flags |= MSG_TRUNC;
1724 		rc = skb_copy_datagram_msg(skb, hlen, m, copy);
1725 	} else {
1726 		copy = 0;
1727 		rc = 0;
1728 		if (err != TIPC_CONN_SHUTDOWN && connected && !m->msg_control)
1729 			rc = -ECONNRESET;
1730 	}
1731 	if (unlikely(rc))
1732 		goto exit;
1733 
1734 	/* Mark message as group event if applicable */
1735 	if (unlikely(grp_evt)) {
1736 		if (msg_grp_evt(hdr) == TIPC_WITHDRAWN)
1737 			m->msg_flags |= MSG_EOR;
1738 		m->msg_flags |= MSG_OOB;
1739 		copy = 0;
1740 	}
1741 
1742 	/* Caption of data or error code/rejected data was successful */
1743 	if (unlikely(flags & MSG_PEEK))
1744 		goto exit;
1745 
1746 	/* Send group flow control advertisement when applicable */
1747 	if (tsk->group && msg_in_group(hdr) && !grp_evt) {
1748 		skb_queue_head_init(&xmitq);
1749 		tipc_group_update_rcv_win(tsk->group, tsk_blocks(hlen + dlen),
1750 					  msg_orignode(hdr), msg_origport(hdr),
1751 					  &xmitq);
1752 		tipc_node_distr_xmit(sock_net(sk), &xmitq);
1753 	}
1754 
1755 	tsk_advance_rx_queue(sk);
1756 
1757 	if (likely(!connected))
1758 		goto exit;
1759 
1760 	/* Send connection flow control advertisement when applicable */
1761 	tsk->rcv_unacked += tsk_inc(tsk, hlen + dlen);
1762 	if (tsk->rcv_unacked >= tsk->rcv_win / TIPC_ACK_RATE)
1763 		tipc_sk_send_ack(tsk);
1764 exit:
1765 	release_sock(sk);
1766 	return rc ? rc : copy;
1767 }
1768 
1769 /**
1770  * tipc_recvstream - receive stream-oriented data
1771  * @m: descriptor for message info
1772  * @buflen: total size of user buffer area
1773  * @flags: receive flags
1774  *
1775  * Used for SOCK_STREAM messages only.  If not enough data is available
1776  * will optionally wait for more; never truncates data.
1777  *
1778  * Returns size of returned message data, errno otherwise
1779  */
1780 static int tipc_recvstream(struct socket *sock, struct msghdr *m,
1781 			   size_t buflen, int flags)
1782 {
1783 	struct sock *sk = sock->sk;
1784 	struct tipc_sock *tsk = tipc_sk(sk);
1785 	struct sk_buff *skb;
1786 	struct tipc_msg *hdr;
1787 	struct tipc_skb_cb *skb_cb;
1788 	bool peek = flags & MSG_PEEK;
1789 	int offset, required, copy, copied = 0;
1790 	int hlen, dlen, err, rc;
1791 	long timeout;
1792 
1793 	/* Catch invalid receive attempts */
1794 	if (unlikely(!buflen))
1795 		return -EINVAL;
1796 
1797 	lock_sock(sk);
1798 
1799 	if (unlikely(sk->sk_state == TIPC_OPEN)) {
1800 		rc = -ENOTCONN;
1801 		goto exit;
1802 	}
1803 	required = sock_rcvlowat(sk, flags & MSG_WAITALL, buflen);
1804 	timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
1805 
1806 	do {
1807 		/* Look at first msg in receive queue; wait if necessary */
1808 		rc = tipc_wait_for_rcvmsg(sock, &timeout);
1809 		if (unlikely(rc))
1810 			break;
1811 		skb = skb_peek(&sk->sk_receive_queue);
1812 		skb_cb = TIPC_SKB_CB(skb);
1813 		hdr = buf_msg(skb);
1814 		dlen = msg_data_sz(hdr);
1815 		hlen = msg_hdr_sz(hdr);
1816 		err = msg_errcode(hdr);
1817 
1818 		/* Discard any empty non-errored (SYN-) message */
1819 		if (unlikely(!dlen && !err)) {
1820 			tsk_advance_rx_queue(sk);
1821 			continue;
1822 		}
1823 
1824 		/* Collect msg meta data, incl. error code and rejected data */
1825 		if (!copied) {
1826 			tipc_sk_set_orig_addr(m, skb);
1827 			rc = tipc_sk_anc_data_recv(m, hdr, tsk);
1828 			if (rc)
1829 				break;
1830 		}
1831 
1832 		/* Copy data if msg ok, otherwise return error/partial data */
1833 		if (likely(!err)) {
1834 			offset = skb_cb->bytes_read;
1835 			copy = min_t(int, dlen - offset, buflen - copied);
1836 			rc = skb_copy_datagram_msg(skb, hlen + offset, m, copy);
1837 			if (unlikely(rc))
1838 				break;
1839 			copied += copy;
1840 			offset += copy;
1841 			if (unlikely(offset < dlen)) {
1842 				if (!peek)
1843 					skb_cb->bytes_read = offset;
1844 				break;
1845 			}
1846 		} else {
1847 			rc = 0;
1848 			if ((err != TIPC_CONN_SHUTDOWN) && !m->msg_control)
1849 				rc = -ECONNRESET;
1850 			if (copied || rc)
1851 				break;
1852 		}
1853 
1854 		if (unlikely(peek))
1855 			break;
1856 
1857 		tsk_advance_rx_queue(sk);
1858 
1859 		/* Send connection flow control advertisement when applicable */
1860 		tsk->rcv_unacked += tsk_inc(tsk, hlen + dlen);
1861 		if (unlikely(tsk->rcv_unacked >= tsk->rcv_win / TIPC_ACK_RATE))
1862 			tipc_sk_send_ack(tsk);
1863 
1864 		/* Exit if all requested data or FIN/error received */
1865 		if (copied == buflen || err)
1866 			break;
1867 
1868 	} while (!skb_queue_empty(&sk->sk_receive_queue) || copied < required);
1869 exit:
1870 	release_sock(sk);
1871 	return copied ? copied : rc;
1872 }
1873 
1874 /**
1875  * tipc_write_space - wake up thread if port congestion is released
1876  * @sk: socket
1877  */
1878 static void tipc_write_space(struct sock *sk)
1879 {
1880 	struct socket_wq *wq;
1881 
1882 	rcu_read_lock();
1883 	wq = rcu_dereference(sk->sk_wq);
1884 	if (skwq_has_sleeper(wq))
1885 		wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
1886 						POLLWRNORM | POLLWRBAND);
1887 	rcu_read_unlock();
1888 }
1889 
1890 /**
1891  * tipc_data_ready - wake up threads to indicate messages have been received
1892  * @sk: socket
1893  * @len: the length of messages
1894  */
1895 static void tipc_data_ready(struct sock *sk)
1896 {
1897 	struct socket_wq *wq;
1898 
1899 	rcu_read_lock();
1900 	wq = rcu_dereference(sk->sk_wq);
1901 	if (skwq_has_sleeper(wq))
1902 		wake_up_interruptible_sync_poll(&wq->wait, POLLIN |
1903 						POLLRDNORM | POLLRDBAND);
1904 	rcu_read_unlock();
1905 }
1906 
1907 static void tipc_sock_destruct(struct sock *sk)
1908 {
1909 	__skb_queue_purge(&sk->sk_receive_queue);
1910 }
1911 
1912 static void tipc_sk_proto_rcv(struct sock *sk,
1913 			      struct sk_buff_head *inputq,
1914 			      struct sk_buff_head *xmitq)
1915 {
1916 	struct sk_buff *skb = __skb_dequeue(inputq);
1917 	struct tipc_sock *tsk = tipc_sk(sk);
1918 	struct tipc_msg *hdr = buf_msg(skb);
1919 	struct tipc_group *grp = tsk->group;
1920 	bool wakeup = false;
1921 
1922 	switch (msg_user(hdr)) {
1923 	case CONN_MANAGER:
1924 		tipc_sk_conn_proto_rcv(tsk, skb, xmitq);
1925 		return;
1926 	case SOCK_WAKEUP:
1927 		tipc_dest_del(&tsk->cong_links, msg_orignode(hdr), 0);
1928 		tsk->cong_link_cnt--;
1929 		wakeup = true;
1930 		break;
1931 	case GROUP_PROTOCOL:
1932 		tipc_group_proto_rcv(grp, &wakeup, hdr, inputq, xmitq);
1933 		break;
1934 	case TOP_SRV:
1935 		tipc_group_member_evt(tsk->group, &wakeup, &sk->sk_rcvbuf,
1936 				      skb, inputq, xmitq);
1937 		skb = NULL;
1938 		break;
1939 	default:
1940 		break;
1941 	}
1942 
1943 	if (wakeup)
1944 		sk->sk_write_space(sk);
1945 
1946 	kfree_skb(skb);
1947 }
1948 
1949 /**
1950  * tipc_filter_connect - Handle incoming message for a connection-based socket
1951  * @tsk: TIPC socket
1952  * @skb: pointer to message buffer. Set to NULL if buffer is consumed
1953  *
1954  * Returns true if everything ok, false otherwise
1955  */
1956 static bool tipc_sk_filter_connect(struct tipc_sock *tsk, struct sk_buff *skb)
1957 {
1958 	struct sock *sk = &tsk->sk;
1959 	struct net *net = sock_net(sk);
1960 	struct tipc_msg *hdr = buf_msg(skb);
1961 	u32 pport = msg_origport(hdr);
1962 	u32 pnode = msg_orignode(hdr);
1963 
1964 	if (unlikely(msg_mcast(hdr)))
1965 		return false;
1966 
1967 	switch (sk->sk_state) {
1968 	case TIPC_CONNECTING:
1969 		/* Accept only ACK or NACK message */
1970 		if (unlikely(!msg_connected(hdr))) {
1971 			if (pport != tsk_peer_port(tsk) ||
1972 			    pnode != tsk_peer_node(tsk))
1973 				return false;
1974 
1975 			tipc_set_sk_state(sk, TIPC_DISCONNECTING);
1976 			sk->sk_err = ECONNREFUSED;
1977 			sk->sk_state_change(sk);
1978 			return true;
1979 		}
1980 
1981 		if (unlikely(msg_errcode(hdr))) {
1982 			tipc_set_sk_state(sk, TIPC_DISCONNECTING);
1983 			sk->sk_err = ECONNREFUSED;
1984 			sk->sk_state_change(sk);
1985 			return true;
1986 		}
1987 
1988 		if (unlikely(!msg_isdata(hdr))) {
1989 			tipc_set_sk_state(sk, TIPC_DISCONNECTING);
1990 			sk->sk_err = EINVAL;
1991 			sk->sk_state_change(sk);
1992 			return true;
1993 		}
1994 
1995 		tipc_sk_finish_conn(tsk, msg_origport(hdr), msg_orignode(hdr));
1996 		msg_set_importance(&tsk->phdr, msg_importance(hdr));
1997 
1998 		/* If 'ACK+' message, add to socket receive queue */
1999 		if (msg_data_sz(hdr))
2000 			return true;
2001 
2002 		/* If empty 'ACK-' message, wake up sleeping connect() */
2003 		sk->sk_data_ready(sk);
2004 
2005 		/* 'ACK-' message is neither accepted nor rejected: */
2006 		msg_set_dest_droppable(hdr, 1);
2007 		return false;
2008 
2009 	case TIPC_OPEN:
2010 	case TIPC_DISCONNECTING:
2011 		break;
2012 	case TIPC_LISTEN:
2013 		/* Accept only SYN message */
2014 		if (!msg_connected(hdr) && !(msg_errcode(hdr)))
2015 			return true;
2016 		break;
2017 	case TIPC_ESTABLISHED:
2018 		/* Accept only connection-based messages sent by peer */
2019 		if (unlikely(!tsk_peer_msg(tsk, hdr)))
2020 			return false;
2021 
2022 		if (unlikely(msg_errcode(hdr))) {
2023 			tipc_set_sk_state(sk, TIPC_DISCONNECTING);
2024 			/* Let timer expire on it's own */
2025 			tipc_node_remove_conn(net, tsk_peer_node(tsk),
2026 					      tsk->portid);
2027 			sk->sk_state_change(sk);
2028 		}
2029 		return true;
2030 	default:
2031 		pr_err("Unknown sk_state %u\n", sk->sk_state);
2032 	}
2033 
2034 	return false;
2035 }
2036 
2037 /**
2038  * rcvbuf_limit - get proper overload limit of socket receive queue
2039  * @sk: socket
2040  * @skb: message
2041  *
2042  * For connection oriented messages, irrespective of importance,
2043  * default queue limit is 2 MB.
2044  *
2045  * For connectionless messages, queue limits are based on message
2046  * importance as follows:
2047  *
2048  * TIPC_LOW_IMPORTANCE       (2 MB)
2049  * TIPC_MEDIUM_IMPORTANCE    (4 MB)
2050  * TIPC_HIGH_IMPORTANCE      (8 MB)
2051  * TIPC_CRITICAL_IMPORTANCE  (16 MB)
2052  *
2053  * Returns overload limit according to corresponding message importance
2054  */
2055 static unsigned int rcvbuf_limit(struct sock *sk, struct sk_buff *skb)
2056 {
2057 	struct tipc_sock *tsk = tipc_sk(sk);
2058 	struct tipc_msg *hdr = buf_msg(skb);
2059 
2060 	if (unlikely(msg_in_group(hdr)))
2061 		return sk->sk_rcvbuf;
2062 
2063 	if (unlikely(!msg_connected(hdr)))
2064 		return sk->sk_rcvbuf << msg_importance(hdr);
2065 
2066 	if (likely(tsk->peer_caps & TIPC_BLOCK_FLOWCTL))
2067 		return sk->sk_rcvbuf;
2068 
2069 	return FLOWCTL_MSG_LIM;
2070 }
2071 
2072 /**
2073  * tipc_sk_filter_rcv - validate incoming message
2074  * @sk: socket
2075  * @skb: pointer to message.
2076  *
2077  * Enqueues message on receive queue if acceptable; optionally handles
2078  * disconnect indication for a connected socket.
2079  *
2080  * Called with socket lock already taken
2081  *
2082  */
2083 static void tipc_sk_filter_rcv(struct sock *sk, struct sk_buff *skb,
2084 			       struct sk_buff_head *xmitq)
2085 {
2086 	bool sk_conn = !tipc_sk_type_connectionless(sk);
2087 	struct tipc_sock *tsk = tipc_sk(sk);
2088 	struct tipc_group *grp = tsk->group;
2089 	struct tipc_msg *hdr = buf_msg(skb);
2090 	struct net *net = sock_net(sk);
2091 	struct sk_buff_head inputq;
2092 	int limit, err = TIPC_OK;
2093 
2094 	TIPC_SKB_CB(skb)->bytes_read = 0;
2095 	__skb_queue_head_init(&inputq);
2096 	__skb_queue_tail(&inputq, skb);
2097 
2098 	if (unlikely(!msg_isdata(hdr)))
2099 		tipc_sk_proto_rcv(sk, &inputq, xmitq);
2100 
2101 	if (unlikely(grp))
2102 		tipc_group_filter_msg(grp, &inputq, xmitq);
2103 
2104 	/* Validate and add to receive buffer if there is space */
2105 	while ((skb = __skb_dequeue(&inputq))) {
2106 		hdr = buf_msg(skb);
2107 		limit = rcvbuf_limit(sk, skb);
2108 		if ((sk_conn && !tipc_sk_filter_connect(tsk, skb)) ||
2109 		    (!sk_conn && msg_connected(hdr)) ||
2110 		    (!grp && msg_in_group(hdr)))
2111 			err = TIPC_ERR_NO_PORT;
2112 		else if (sk_rmem_alloc_get(sk) + skb->truesize >= limit)
2113 			err = TIPC_ERR_OVERLOAD;
2114 
2115 		if (unlikely(err)) {
2116 			tipc_skb_reject(net, err, skb, xmitq);
2117 			err = TIPC_OK;
2118 			continue;
2119 		}
2120 		__skb_queue_tail(&sk->sk_receive_queue, skb);
2121 		skb_set_owner_r(skb, sk);
2122 		sk->sk_data_ready(sk);
2123 	}
2124 }
2125 
2126 /**
2127  * tipc_sk_backlog_rcv - handle incoming message from backlog queue
2128  * @sk: socket
2129  * @skb: message
2130  *
2131  * Caller must hold socket lock
2132  */
2133 static int tipc_sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
2134 {
2135 	unsigned int before = sk_rmem_alloc_get(sk);
2136 	struct sk_buff_head xmitq;
2137 	unsigned int added;
2138 
2139 	__skb_queue_head_init(&xmitq);
2140 
2141 	tipc_sk_filter_rcv(sk, skb, &xmitq);
2142 	added = sk_rmem_alloc_get(sk) - before;
2143 	atomic_add(added, &tipc_sk(sk)->dupl_rcvcnt);
2144 
2145 	/* Send pending response/rejected messages, if any */
2146 	tipc_node_distr_xmit(sock_net(sk), &xmitq);
2147 	return 0;
2148 }
2149 
2150 /**
2151  * tipc_sk_enqueue - extract all buffers with destination 'dport' from
2152  *                   inputq and try adding them to socket or backlog queue
2153  * @inputq: list of incoming buffers with potentially different destinations
2154  * @sk: socket where the buffers should be enqueued
2155  * @dport: port number for the socket
2156  *
2157  * Caller must hold socket lock
2158  */
2159 static void tipc_sk_enqueue(struct sk_buff_head *inputq, struct sock *sk,
2160 			    u32 dport, struct sk_buff_head *xmitq)
2161 {
2162 	unsigned long time_limit = jiffies + 2;
2163 	struct sk_buff *skb;
2164 	unsigned int lim;
2165 	atomic_t *dcnt;
2166 	u32 onode;
2167 
2168 	while (skb_queue_len(inputq)) {
2169 		if (unlikely(time_after_eq(jiffies, time_limit)))
2170 			return;
2171 
2172 		skb = tipc_skb_dequeue(inputq, dport);
2173 		if (unlikely(!skb))
2174 			return;
2175 
2176 		/* Add message directly to receive queue if possible */
2177 		if (!sock_owned_by_user(sk)) {
2178 			tipc_sk_filter_rcv(sk, skb, xmitq);
2179 			continue;
2180 		}
2181 
2182 		/* Try backlog, compensating for double-counted bytes */
2183 		dcnt = &tipc_sk(sk)->dupl_rcvcnt;
2184 		if (!sk->sk_backlog.len)
2185 			atomic_set(dcnt, 0);
2186 		lim = rcvbuf_limit(sk, skb) + atomic_read(dcnt);
2187 		if (likely(!sk_add_backlog(sk, skb, lim)))
2188 			continue;
2189 
2190 		/* Overload => reject message back to sender */
2191 		onode = tipc_own_addr(sock_net(sk));
2192 		if (tipc_msg_reverse(onode, &skb, TIPC_ERR_OVERLOAD))
2193 			__skb_queue_tail(xmitq, skb);
2194 		break;
2195 	}
2196 }
2197 
2198 /**
2199  * tipc_sk_rcv - handle a chain of incoming buffers
2200  * @inputq: buffer list containing the buffers
2201  * Consumes all buffers in list until inputq is empty
2202  * Note: may be called in multiple threads referring to the same queue
2203  */
2204 void tipc_sk_rcv(struct net *net, struct sk_buff_head *inputq)
2205 {
2206 	struct sk_buff_head xmitq;
2207 	u32 dnode, dport = 0;
2208 	int err;
2209 	struct tipc_sock *tsk;
2210 	struct sock *sk;
2211 	struct sk_buff *skb;
2212 
2213 	__skb_queue_head_init(&xmitq);
2214 	while (skb_queue_len(inputq)) {
2215 		dport = tipc_skb_peek_port(inputq, dport);
2216 		tsk = tipc_sk_lookup(net, dport);
2217 
2218 		if (likely(tsk)) {
2219 			sk = &tsk->sk;
2220 			if (likely(spin_trylock_bh(&sk->sk_lock.slock))) {
2221 				tipc_sk_enqueue(inputq, sk, dport, &xmitq);
2222 				spin_unlock_bh(&sk->sk_lock.slock);
2223 			}
2224 			/* Send pending response/rejected messages, if any */
2225 			tipc_node_distr_xmit(sock_net(sk), &xmitq);
2226 			sock_put(sk);
2227 			continue;
2228 		}
2229 		/* No destination socket => dequeue skb if still there */
2230 		skb = tipc_skb_dequeue(inputq, dport);
2231 		if (!skb)
2232 			return;
2233 
2234 		/* Try secondary lookup if unresolved named message */
2235 		err = TIPC_ERR_NO_PORT;
2236 		if (tipc_msg_lookup_dest(net, skb, &err))
2237 			goto xmit;
2238 
2239 		/* Prepare for message rejection */
2240 		if (!tipc_msg_reverse(tipc_own_addr(net), &skb, err))
2241 			continue;
2242 xmit:
2243 		dnode = msg_destnode(buf_msg(skb));
2244 		tipc_node_xmit_skb(net, skb, dnode, dport);
2245 	}
2246 }
2247 
2248 static int tipc_wait_for_connect(struct socket *sock, long *timeo_p)
2249 {
2250 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
2251 	struct sock *sk = sock->sk;
2252 	int done;
2253 
2254 	do {
2255 		int err = sock_error(sk);
2256 		if (err)
2257 			return err;
2258 		if (!*timeo_p)
2259 			return -ETIMEDOUT;
2260 		if (signal_pending(current))
2261 			return sock_intr_errno(*timeo_p);
2262 
2263 		add_wait_queue(sk_sleep(sk), &wait);
2264 		done = sk_wait_event(sk, timeo_p,
2265 				     sk->sk_state != TIPC_CONNECTING, &wait);
2266 		remove_wait_queue(sk_sleep(sk), &wait);
2267 	} while (!done);
2268 	return 0;
2269 }
2270 
2271 /**
2272  * tipc_connect - establish a connection to another TIPC port
2273  * @sock: socket structure
2274  * @dest: socket address for destination port
2275  * @destlen: size of socket address data structure
2276  * @flags: file-related flags associated with socket
2277  *
2278  * Returns 0 on success, errno otherwise
2279  */
2280 static int tipc_connect(struct socket *sock, struct sockaddr *dest,
2281 			int destlen, int flags)
2282 {
2283 	struct sock *sk = sock->sk;
2284 	struct tipc_sock *tsk = tipc_sk(sk);
2285 	struct sockaddr_tipc *dst = (struct sockaddr_tipc *)dest;
2286 	struct msghdr m = {NULL,};
2287 	long timeout = (flags & O_NONBLOCK) ? 0 : tsk->conn_timeout;
2288 	int previous;
2289 	int res = 0;
2290 
2291 	if (destlen != sizeof(struct sockaddr_tipc))
2292 		return -EINVAL;
2293 
2294 	lock_sock(sk);
2295 
2296 	if (tsk->group) {
2297 		res = -EINVAL;
2298 		goto exit;
2299 	}
2300 
2301 	if (dst->family == AF_UNSPEC) {
2302 		memset(&tsk->peer, 0, sizeof(struct sockaddr_tipc));
2303 		if (!tipc_sk_type_connectionless(sk))
2304 			res = -EINVAL;
2305 		goto exit;
2306 	} else if (dst->family != AF_TIPC) {
2307 		res = -EINVAL;
2308 	}
2309 	if (dst->addrtype != TIPC_ADDR_ID && dst->addrtype != TIPC_ADDR_NAME)
2310 		res = -EINVAL;
2311 	if (res)
2312 		goto exit;
2313 
2314 	/* DGRAM/RDM connect(), just save the destaddr */
2315 	if (tipc_sk_type_connectionless(sk)) {
2316 		memcpy(&tsk->peer, dest, destlen);
2317 		goto exit;
2318 	}
2319 
2320 	previous = sk->sk_state;
2321 
2322 	switch (sk->sk_state) {
2323 	case TIPC_OPEN:
2324 		/* Send a 'SYN-' to destination */
2325 		m.msg_name = dest;
2326 		m.msg_namelen = destlen;
2327 
2328 		/* If connect is in non-blocking case, set MSG_DONTWAIT to
2329 		 * indicate send_msg() is never blocked.
2330 		 */
2331 		if (!timeout)
2332 			m.msg_flags = MSG_DONTWAIT;
2333 
2334 		res = __tipc_sendmsg(sock, &m, 0);
2335 		if ((res < 0) && (res != -EWOULDBLOCK))
2336 			goto exit;
2337 
2338 		/* Just entered TIPC_CONNECTING state; the only
2339 		 * difference is that return value in non-blocking
2340 		 * case is EINPROGRESS, rather than EALREADY.
2341 		 */
2342 		res = -EINPROGRESS;
2343 		/* fall thru' */
2344 	case TIPC_CONNECTING:
2345 		if (!timeout) {
2346 			if (previous == TIPC_CONNECTING)
2347 				res = -EALREADY;
2348 			goto exit;
2349 		}
2350 		timeout = msecs_to_jiffies(timeout);
2351 		/* Wait until an 'ACK' or 'RST' arrives, or a timeout occurs */
2352 		res = tipc_wait_for_connect(sock, &timeout);
2353 		break;
2354 	case TIPC_ESTABLISHED:
2355 		res = -EISCONN;
2356 		break;
2357 	default:
2358 		res = -EINVAL;
2359 	}
2360 
2361 exit:
2362 	release_sock(sk);
2363 	return res;
2364 }
2365 
2366 /**
2367  * tipc_listen - allow socket to listen for incoming connections
2368  * @sock: socket structure
2369  * @len: (unused)
2370  *
2371  * Returns 0 on success, errno otherwise
2372  */
2373 static int tipc_listen(struct socket *sock, int len)
2374 {
2375 	struct sock *sk = sock->sk;
2376 	int res;
2377 
2378 	lock_sock(sk);
2379 	res = tipc_set_sk_state(sk, TIPC_LISTEN);
2380 	release_sock(sk);
2381 
2382 	return res;
2383 }
2384 
2385 static int tipc_wait_for_accept(struct socket *sock, long timeo)
2386 {
2387 	struct sock *sk = sock->sk;
2388 	DEFINE_WAIT(wait);
2389 	int err;
2390 
2391 	/* True wake-one mechanism for incoming connections: only
2392 	 * one process gets woken up, not the 'whole herd'.
2393 	 * Since we do not 'race & poll' for established sockets
2394 	 * anymore, the common case will execute the loop only once.
2395 	*/
2396 	for (;;) {
2397 		prepare_to_wait_exclusive(sk_sleep(sk), &wait,
2398 					  TASK_INTERRUPTIBLE);
2399 		if (timeo && skb_queue_empty(&sk->sk_receive_queue)) {
2400 			release_sock(sk);
2401 			timeo = schedule_timeout(timeo);
2402 			lock_sock(sk);
2403 		}
2404 		err = 0;
2405 		if (!skb_queue_empty(&sk->sk_receive_queue))
2406 			break;
2407 		err = -EAGAIN;
2408 		if (!timeo)
2409 			break;
2410 		err = sock_intr_errno(timeo);
2411 		if (signal_pending(current))
2412 			break;
2413 	}
2414 	finish_wait(sk_sleep(sk), &wait);
2415 	return err;
2416 }
2417 
2418 /**
2419  * tipc_accept - wait for connection request
2420  * @sock: listening socket
2421  * @newsock: new socket that is to be connected
2422  * @flags: file-related flags associated with socket
2423  *
2424  * Returns 0 on success, errno otherwise
2425  */
2426 static int tipc_accept(struct socket *sock, struct socket *new_sock, int flags,
2427 		       bool kern)
2428 {
2429 	struct sock *new_sk, *sk = sock->sk;
2430 	struct sk_buff *buf;
2431 	struct tipc_sock *new_tsock;
2432 	struct tipc_msg *msg;
2433 	long timeo;
2434 	int res;
2435 
2436 	lock_sock(sk);
2437 
2438 	if (sk->sk_state != TIPC_LISTEN) {
2439 		res = -EINVAL;
2440 		goto exit;
2441 	}
2442 	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
2443 	res = tipc_wait_for_accept(sock, timeo);
2444 	if (res)
2445 		goto exit;
2446 
2447 	buf = skb_peek(&sk->sk_receive_queue);
2448 
2449 	res = tipc_sk_create(sock_net(sock->sk), new_sock, 0, kern);
2450 	if (res)
2451 		goto exit;
2452 	security_sk_clone(sock->sk, new_sock->sk);
2453 
2454 	new_sk = new_sock->sk;
2455 	new_tsock = tipc_sk(new_sk);
2456 	msg = buf_msg(buf);
2457 
2458 	/* we lock on new_sk; but lockdep sees the lock on sk */
2459 	lock_sock_nested(new_sk, SINGLE_DEPTH_NESTING);
2460 
2461 	/*
2462 	 * Reject any stray messages received by new socket
2463 	 * before the socket lock was taken (very, very unlikely)
2464 	 */
2465 	tsk_rej_rx_queue(new_sk);
2466 
2467 	/* Connect new socket to it's peer */
2468 	tipc_sk_finish_conn(new_tsock, msg_origport(msg), msg_orignode(msg));
2469 
2470 	tsk_set_importance(new_tsock, msg_importance(msg));
2471 	if (msg_named(msg)) {
2472 		new_tsock->conn_type = msg_nametype(msg);
2473 		new_tsock->conn_instance = msg_nameinst(msg);
2474 	}
2475 
2476 	/*
2477 	 * Respond to 'SYN-' by discarding it & returning 'ACK'-.
2478 	 * Respond to 'SYN+' by queuing it on new socket.
2479 	 */
2480 	if (!msg_data_sz(msg)) {
2481 		struct msghdr m = {NULL,};
2482 
2483 		tsk_advance_rx_queue(sk);
2484 		__tipc_sendstream(new_sock, &m, 0);
2485 	} else {
2486 		__skb_dequeue(&sk->sk_receive_queue);
2487 		__skb_queue_head(&new_sk->sk_receive_queue, buf);
2488 		skb_set_owner_r(buf, new_sk);
2489 	}
2490 	release_sock(new_sk);
2491 exit:
2492 	release_sock(sk);
2493 	return res;
2494 }
2495 
2496 /**
2497  * tipc_shutdown - shutdown socket connection
2498  * @sock: socket structure
2499  * @how: direction to close (must be SHUT_RDWR)
2500  *
2501  * Terminates connection (if necessary), then purges socket's receive queue.
2502  *
2503  * Returns 0 on success, errno otherwise
2504  */
2505 static int tipc_shutdown(struct socket *sock, int how)
2506 {
2507 	struct sock *sk = sock->sk;
2508 	int res;
2509 
2510 	if (how != SHUT_RDWR)
2511 		return -EINVAL;
2512 
2513 	lock_sock(sk);
2514 
2515 	__tipc_shutdown(sock, TIPC_CONN_SHUTDOWN);
2516 	sk->sk_shutdown = SEND_SHUTDOWN;
2517 
2518 	if (sk->sk_state == TIPC_DISCONNECTING) {
2519 		/* Discard any unreceived messages */
2520 		__skb_queue_purge(&sk->sk_receive_queue);
2521 
2522 		/* Wake up anyone sleeping in poll */
2523 		sk->sk_state_change(sk);
2524 		res = 0;
2525 	} else {
2526 		res = -ENOTCONN;
2527 	}
2528 
2529 	release_sock(sk);
2530 	return res;
2531 }
2532 
2533 static void tipc_sk_timeout(struct timer_list *t)
2534 {
2535 	struct sock *sk = from_timer(sk, t, sk_timer);
2536 	struct tipc_sock *tsk = tipc_sk(sk);
2537 	u32 peer_port = tsk_peer_port(tsk);
2538 	u32 peer_node = tsk_peer_node(tsk);
2539 	u32 own_node = tsk_own_node(tsk);
2540 	u32 own_port = tsk->portid;
2541 	struct net *net = sock_net(sk);
2542 	struct sk_buff *skb = NULL;
2543 
2544 	bh_lock_sock(sk);
2545 	if (!tipc_sk_connected(sk))
2546 		goto exit;
2547 
2548 	/* Try again later if socket is busy */
2549 	if (sock_owned_by_user(sk)) {
2550 		sk_reset_timer(sk, &sk->sk_timer, jiffies + HZ / 20);
2551 		goto exit;
2552 	}
2553 
2554 	if (tsk->probe_unacked) {
2555 		tipc_set_sk_state(sk, TIPC_DISCONNECTING);
2556 		tipc_node_remove_conn(net, peer_node, peer_port);
2557 		sk->sk_state_change(sk);
2558 		goto exit;
2559 	}
2560 	/* Send new probe */
2561 	skb = tipc_msg_create(CONN_MANAGER, CONN_PROBE, INT_H_SIZE, 0,
2562 			      peer_node, own_node, peer_port, own_port,
2563 			      TIPC_OK);
2564 	tsk->probe_unacked = true;
2565 	sk_reset_timer(sk, &sk->sk_timer, jiffies + CONN_PROBING_INTV);
2566 exit:
2567 	bh_unlock_sock(sk);
2568 	if (skb)
2569 		tipc_node_xmit_skb(net, skb, peer_node, own_port);
2570 	sock_put(sk);
2571 }
2572 
2573 static int tipc_sk_publish(struct tipc_sock *tsk, uint scope,
2574 			   struct tipc_name_seq const *seq)
2575 {
2576 	struct sock *sk = &tsk->sk;
2577 	struct net *net = sock_net(sk);
2578 	struct publication *publ;
2579 	u32 key;
2580 
2581 	if (tipc_sk_connected(sk))
2582 		return -EINVAL;
2583 	key = tsk->portid + tsk->pub_count + 1;
2584 	if (key == tsk->portid)
2585 		return -EADDRINUSE;
2586 
2587 	publ = tipc_nametbl_publish(net, seq->type, seq->lower, seq->upper,
2588 				    scope, tsk->portid, key);
2589 	if (unlikely(!publ))
2590 		return -EINVAL;
2591 
2592 	list_add(&publ->pport_list, &tsk->publications);
2593 	tsk->pub_count++;
2594 	tsk->published = 1;
2595 	return 0;
2596 }
2597 
2598 static int tipc_sk_withdraw(struct tipc_sock *tsk, uint scope,
2599 			    struct tipc_name_seq const *seq)
2600 {
2601 	struct net *net = sock_net(&tsk->sk);
2602 	struct publication *publ;
2603 	struct publication *safe;
2604 	int rc = -EINVAL;
2605 
2606 	list_for_each_entry_safe(publ, safe, &tsk->publications, pport_list) {
2607 		if (seq) {
2608 			if (publ->scope != scope)
2609 				continue;
2610 			if (publ->type != seq->type)
2611 				continue;
2612 			if (publ->lower != seq->lower)
2613 				continue;
2614 			if (publ->upper != seq->upper)
2615 				break;
2616 			tipc_nametbl_withdraw(net, publ->type, publ->lower,
2617 					      publ->ref, publ->key);
2618 			rc = 0;
2619 			break;
2620 		}
2621 		tipc_nametbl_withdraw(net, publ->type, publ->lower,
2622 				      publ->ref, publ->key);
2623 		rc = 0;
2624 	}
2625 	if (list_empty(&tsk->publications))
2626 		tsk->published = 0;
2627 	return rc;
2628 }
2629 
2630 /* tipc_sk_reinit: set non-zero address in all existing sockets
2631  *                 when we go from standalone to network mode.
2632  */
2633 void tipc_sk_reinit(struct net *net)
2634 {
2635 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2636 	struct rhashtable_iter iter;
2637 	struct tipc_sock *tsk;
2638 	struct tipc_msg *msg;
2639 
2640 	rhashtable_walk_enter(&tn->sk_rht, &iter);
2641 
2642 	do {
2643 		tsk = ERR_PTR(rhashtable_walk_start(&iter));
2644 		if (IS_ERR(tsk))
2645 			goto walk_stop;
2646 
2647 		while ((tsk = rhashtable_walk_next(&iter)) && !IS_ERR(tsk)) {
2648 			spin_lock_bh(&tsk->sk.sk_lock.slock);
2649 			msg = &tsk->phdr;
2650 			msg_set_prevnode(msg, tn->own_addr);
2651 			msg_set_orignode(msg, tn->own_addr);
2652 			spin_unlock_bh(&tsk->sk.sk_lock.slock);
2653 		}
2654 walk_stop:
2655 		rhashtable_walk_stop(&iter);
2656 	} while (tsk == ERR_PTR(-EAGAIN));
2657 }
2658 
2659 static struct tipc_sock *tipc_sk_lookup(struct net *net, u32 portid)
2660 {
2661 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2662 	struct tipc_sock *tsk;
2663 
2664 	rcu_read_lock();
2665 	tsk = rhashtable_lookup_fast(&tn->sk_rht, &portid, tsk_rht_params);
2666 	if (tsk)
2667 		sock_hold(&tsk->sk);
2668 	rcu_read_unlock();
2669 
2670 	return tsk;
2671 }
2672 
2673 static int tipc_sk_insert(struct tipc_sock *tsk)
2674 {
2675 	struct sock *sk = &tsk->sk;
2676 	struct net *net = sock_net(sk);
2677 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2678 	u32 remaining = (TIPC_MAX_PORT - TIPC_MIN_PORT) + 1;
2679 	u32 portid = prandom_u32() % remaining + TIPC_MIN_PORT;
2680 
2681 	while (remaining--) {
2682 		portid++;
2683 		if ((portid < TIPC_MIN_PORT) || (portid > TIPC_MAX_PORT))
2684 			portid = TIPC_MIN_PORT;
2685 		tsk->portid = portid;
2686 		sock_hold(&tsk->sk);
2687 		if (!rhashtable_lookup_insert_fast(&tn->sk_rht, &tsk->node,
2688 						   tsk_rht_params))
2689 			return 0;
2690 		sock_put(&tsk->sk);
2691 	}
2692 
2693 	return -1;
2694 }
2695 
2696 static void tipc_sk_remove(struct tipc_sock *tsk)
2697 {
2698 	struct sock *sk = &tsk->sk;
2699 	struct tipc_net *tn = net_generic(sock_net(sk), tipc_net_id);
2700 
2701 	if (!rhashtable_remove_fast(&tn->sk_rht, &tsk->node, tsk_rht_params)) {
2702 		WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
2703 		__sock_put(sk);
2704 	}
2705 }
2706 
2707 static const struct rhashtable_params tsk_rht_params = {
2708 	.nelem_hint = 192,
2709 	.head_offset = offsetof(struct tipc_sock, node),
2710 	.key_offset = offsetof(struct tipc_sock, portid),
2711 	.key_len = sizeof(u32), /* portid */
2712 	.max_size = 1048576,
2713 	.min_size = 256,
2714 	.automatic_shrinking = true,
2715 };
2716 
2717 int tipc_sk_rht_init(struct net *net)
2718 {
2719 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2720 
2721 	return rhashtable_init(&tn->sk_rht, &tsk_rht_params);
2722 }
2723 
2724 void tipc_sk_rht_destroy(struct net *net)
2725 {
2726 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2727 
2728 	/* Wait for socket readers to complete */
2729 	synchronize_net();
2730 
2731 	rhashtable_destroy(&tn->sk_rht);
2732 }
2733 
2734 static int tipc_sk_join(struct tipc_sock *tsk, struct tipc_group_req *mreq)
2735 {
2736 	struct net *net = sock_net(&tsk->sk);
2737 	u32 domain = addr_domain(net, mreq->scope);
2738 	struct tipc_group *grp = tsk->group;
2739 	struct tipc_msg *hdr = &tsk->phdr;
2740 	struct tipc_name_seq seq;
2741 	int rc;
2742 
2743 	if (mreq->type < TIPC_RESERVED_TYPES)
2744 		return -EACCES;
2745 	if (grp)
2746 		return -EACCES;
2747 	grp = tipc_group_create(net, tsk->portid, mreq);
2748 	if (!grp)
2749 		return -ENOMEM;
2750 	tsk->group = grp;
2751 	msg_set_lookup_scope(hdr, mreq->scope);
2752 	msg_set_nametype(hdr, mreq->type);
2753 	msg_set_dest_droppable(hdr, true);
2754 	seq.type = mreq->type;
2755 	seq.lower = mreq->instance;
2756 	seq.upper = seq.lower;
2757 	tipc_nametbl_build_group(net, grp, mreq->type, domain);
2758 	rc = tipc_sk_publish(tsk, mreq->scope, &seq);
2759 	if (rc) {
2760 		tipc_group_delete(net, grp);
2761 		tsk->group = NULL;
2762 	}
2763 
2764 	/* Eliminate any risk that a broadcast overtakes the sent JOIN */
2765 	tsk->mc_method.rcast = true;
2766 	tsk->mc_method.mandatory = true;
2767 	return rc;
2768 }
2769 
2770 static int tipc_sk_leave(struct tipc_sock *tsk)
2771 {
2772 	struct net *net = sock_net(&tsk->sk);
2773 	struct tipc_group *grp = tsk->group;
2774 	struct tipc_name_seq seq;
2775 	int scope;
2776 
2777 	if (!grp)
2778 		return -EINVAL;
2779 	tipc_group_self(grp, &seq, &scope);
2780 	tipc_group_delete(net, grp);
2781 	tsk->group = NULL;
2782 	tipc_sk_withdraw(tsk, scope, &seq);
2783 	return 0;
2784 }
2785 
2786 /**
2787  * tipc_setsockopt - set socket option
2788  * @sock: socket structure
2789  * @lvl: option level
2790  * @opt: option identifier
2791  * @ov: pointer to new option value
2792  * @ol: length of option value
2793  *
2794  * For stream sockets only, accepts and ignores all IPPROTO_TCP options
2795  * (to ease compatibility).
2796  *
2797  * Returns 0 on success, errno otherwise
2798  */
2799 static int tipc_setsockopt(struct socket *sock, int lvl, int opt,
2800 			   char __user *ov, unsigned int ol)
2801 {
2802 	struct sock *sk = sock->sk;
2803 	struct tipc_sock *tsk = tipc_sk(sk);
2804 	struct tipc_group_req mreq;
2805 	u32 value = 0;
2806 	int res = 0;
2807 
2808 	if ((lvl == IPPROTO_TCP) && (sock->type == SOCK_STREAM))
2809 		return 0;
2810 	if (lvl != SOL_TIPC)
2811 		return -ENOPROTOOPT;
2812 
2813 	switch (opt) {
2814 	case TIPC_IMPORTANCE:
2815 	case TIPC_SRC_DROPPABLE:
2816 	case TIPC_DEST_DROPPABLE:
2817 	case TIPC_CONN_TIMEOUT:
2818 		if (ol < sizeof(value))
2819 			return -EINVAL;
2820 		if (get_user(value, (u32 __user *)ov))
2821 			return -EFAULT;
2822 		break;
2823 	case TIPC_GROUP_JOIN:
2824 		if (ol < sizeof(mreq))
2825 			return -EINVAL;
2826 		if (copy_from_user(&mreq, ov, sizeof(mreq)))
2827 			return -EFAULT;
2828 		break;
2829 	default:
2830 		if (ov || ol)
2831 			return -EINVAL;
2832 	}
2833 
2834 	lock_sock(sk);
2835 
2836 	switch (opt) {
2837 	case TIPC_IMPORTANCE:
2838 		res = tsk_set_importance(tsk, value);
2839 		break;
2840 	case TIPC_SRC_DROPPABLE:
2841 		if (sock->type != SOCK_STREAM)
2842 			tsk_set_unreliable(tsk, value);
2843 		else
2844 			res = -ENOPROTOOPT;
2845 		break;
2846 	case TIPC_DEST_DROPPABLE:
2847 		tsk_set_unreturnable(tsk, value);
2848 		break;
2849 	case TIPC_CONN_TIMEOUT:
2850 		tipc_sk(sk)->conn_timeout = value;
2851 		break;
2852 	case TIPC_MCAST_BROADCAST:
2853 		tsk->mc_method.rcast = false;
2854 		tsk->mc_method.mandatory = true;
2855 		break;
2856 	case TIPC_MCAST_REPLICAST:
2857 		tsk->mc_method.rcast = true;
2858 		tsk->mc_method.mandatory = true;
2859 		break;
2860 	case TIPC_GROUP_JOIN:
2861 		res = tipc_sk_join(tsk, &mreq);
2862 		break;
2863 	case TIPC_GROUP_LEAVE:
2864 		res = tipc_sk_leave(tsk);
2865 		break;
2866 	default:
2867 		res = -EINVAL;
2868 	}
2869 
2870 	release_sock(sk);
2871 
2872 	return res;
2873 }
2874 
2875 /**
2876  * tipc_getsockopt - get socket option
2877  * @sock: socket structure
2878  * @lvl: option level
2879  * @opt: option identifier
2880  * @ov: receptacle for option value
2881  * @ol: receptacle for length of option value
2882  *
2883  * For stream sockets only, returns 0 length result for all IPPROTO_TCP options
2884  * (to ease compatibility).
2885  *
2886  * Returns 0 on success, errno otherwise
2887  */
2888 static int tipc_getsockopt(struct socket *sock, int lvl, int opt,
2889 			   char __user *ov, int __user *ol)
2890 {
2891 	struct sock *sk = sock->sk;
2892 	struct tipc_sock *tsk = tipc_sk(sk);
2893 	struct tipc_name_seq seq;
2894 	int len, scope;
2895 	u32 value;
2896 	int res;
2897 
2898 	if ((lvl == IPPROTO_TCP) && (sock->type == SOCK_STREAM))
2899 		return put_user(0, ol);
2900 	if (lvl != SOL_TIPC)
2901 		return -ENOPROTOOPT;
2902 	res = get_user(len, ol);
2903 	if (res)
2904 		return res;
2905 
2906 	lock_sock(sk);
2907 
2908 	switch (opt) {
2909 	case TIPC_IMPORTANCE:
2910 		value = tsk_importance(tsk);
2911 		break;
2912 	case TIPC_SRC_DROPPABLE:
2913 		value = tsk_unreliable(tsk);
2914 		break;
2915 	case TIPC_DEST_DROPPABLE:
2916 		value = tsk_unreturnable(tsk);
2917 		break;
2918 	case TIPC_CONN_TIMEOUT:
2919 		value = tsk->conn_timeout;
2920 		/* no need to set "res", since already 0 at this point */
2921 		break;
2922 	case TIPC_NODE_RECVQ_DEPTH:
2923 		value = 0; /* was tipc_queue_size, now obsolete */
2924 		break;
2925 	case TIPC_SOCK_RECVQ_DEPTH:
2926 		value = skb_queue_len(&sk->sk_receive_queue);
2927 		break;
2928 	case TIPC_GROUP_JOIN:
2929 		seq.type = 0;
2930 		if (tsk->group)
2931 			tipc_group_self(tsk->group, &seq, &scope);
2932 		value = seq.type;
2933 		break;
2934 	default:
2935 		res = -EINVAL;
2936 	}
2937 
2938 	release_sock(sk);
2939 
2940 	if (res)
2941 		return res;	/* "get" failed */
2942 
2943 	if (len < sizeof(value))
2944 		return -EINVAL;
2945 
2946 	if (copy_to_user(ov, &value, sizeof(value)))
2947 		return -EFAULT;
2948 
2949 	return put_user(sizeof(value), ol);
2950 }
2951 
2952 static int tipc_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
2953 {
2954 	struct sock *sk = sock->sk;
2955 	struct tipc_sioc_ln_req lnr;
2956 	void __user *argp = (void __user *)arg;
2957 
2958 	switch (cmd) {
2959 	case SIOCGETLINKNAME:
2960 		if (copy_from_user(&lnr, argp, sizeof(lnr)))
2961 			return -EFAULT;
2962 		if (!tipc_node_get_linkname(sock_net(sk),
2963 					    lnr.bearer_id & 0xffff, lnr.peer,
2964 					    lnr.linkname, TIPC_MAX_LINK_NAME)) {
2965 			if (copy_to_user(argp, &lnr, sizeof(lnr)))
2966 				return -EFAULT;
2967 			return 0;
2968 		}
2969 		return -EADDRNOTAVAIL;
2970 	default:
2971 		return -ENOIOCTLCMD;
2972 	}
2973 }
2974 
2975 static int tipc_socketpair(struct socket *sock1, struct socket *sock2)
2976 {
2977 	struct tipc_sock *tsk2 = tipc_sk(sock2->sk);
2978 	struct tipc_sock *tsk1 = tipc_sk(sock1->sk);
2979 	u32 onode = tipc_own_addr(sock_net(sock1->sk));
2980 
2981 	tsk1->peer.family = AF_TIPC;
2982 	tsk1->peer.addrtype = TIPC_ADDR_ID;
2983 	tsk1->peer.scope = TIPC_NODE_SCOPE;
2984 	tsk1->peer.addr.id.ref = tsk2->portid;
2985 	tsk1->peer.addr.id.node = onode;
2986 	tsk2->peer.family = AF_TIPC;
2987 	tsk2->peer.addrtype = TIPC_ADDR_ID;
2988 	tsk2->peer.scope = TIPC_NODE_SCOPE;
2989 	tsk2->peer.addr.id.ref = tsk1->portid;
2990 	tsk2->peer.addr.id.node = onode;
2991 
2992 	tipc_sk_finish_conn(tsk1, tsk2->portid, onode);
2993 	tipc_sk_finish_conn(tsk2, tsk1->portid, onode);
2994 	return 0;
2995 }
2996 
2997 /* Protocol switches for the various types of TIPC sockets */
2998 
2999 static const struct proto_ops msg_ops = {
3000 	.owner		= THIS_MODULE,
3001 	.family		= AF_TIPC,
3002 	.release	= tipc_release,
3003 	.bind		= tipc_bind,
3004 	.connect	= tipc_connect,
3005 	.socketpair	= tipc_socketpair,
3006 	.accept		= sock_no_accept,
3007 	.getname	= tipc_getname,
3008 	.poll		= tipc_poll,
3009 	.ioctl		= tipc_ioctl,
3010 	.listen		= sock_no_listen,
3011 	.shutdown	= tipc_shutdown,
3012 	.setsockopt	= tipc_setsockopt,
3013 	.getsockopt	= tipc_getsockopt,
3014 	.sendmsg	= tipc_sendmsg,
3015 	.recvmsg	= tipc_recvmsg,
3016 	.mmap		= sock_no_mmap,
3017 	.sendpage	= sock_no_sendpage
3018 };
3019 
3020 static const struct proto_ops packet_ops = {
3021 	.owner		= THIS_MODULE,
3022 	.family		= AF_TIPC,
3023 	.release	= tipc_release,
3024 	.bind		= tipc_bind,
3025 	.connect	= tipc_connect,
3026 	.socketpair	= tipc_socketpair,
3027 	.accept		= tipc_accept,
3028 	.getname	= tipc_getname,
3029 	.poll		= tipc_poll,
3030 	.ioctl		= tipc_ioctl,
3031 	.listen		= tipc_listen,
3032 	.shutdown	= tipc_shutdown,
3033 	.setsockopt	= tipc_setsockopt,
3034 	.getsockopt	= tipc_getsockopt,
3035 	.sendmsg	= tipc_send_packet,
3036 	.recvmsg	= tipc_recvmsg,
3037 	.mmap		= sock_no_mmap,
3038 	.sendpage	= sock_no_sendpage
3039 };
3040 
3041 static const struct proto_ops stream_ops = {
3042 	.owner		= THIS_MODULE,
3043 	.family		= AF_TIPC,
3044 	.release	= tipc_release,
3045 	.bind		= tipc_bind,
3046 	.connect	= tipc_connect,
3047 	.socketpair	= tipc_socketpair,
3048 	.accept		= tipc_accept,
3049 	.getname	= tipc_getname,
3050 	.poll		= tipc_poll,
3051 	.ioctl		= tipc_ioctl,
3052 	.listen		= tipc_listen,
3053 	.shutdown	= tipc_shutdown,
3054 	.setsockopt	= tipc_setsockopt,
3055 	.getsockopt	= tipc_getsockopt,
3056 	.sendmsg	= tipc_sendstream,
3057 	.recvmsg	= tipc_recvstream,
3058 	.mmap		= sock_no_mmap,
3059 	.sendpage	= sock_no_sendpage
3060 };
3061 
3062 static const struct net_proto_family tipc_family_ops = {
3063 	.owner		= THIS_MODULE,
3064 	.family		= AF_TIPC,
3065 	.create		= tipc_sk_create
3066 };
3067 
3068 static struct proto tipc_proto = {
3069 	.name		= "TIPC",
3070 	.owner		= THIS_MODULE,
3071 	.obj_size	= sizeof(struct tipc_sock),
3072 	.sysctl_rmem	= sysctl_tipc_rmem
3073 };
3074 
3075 /**
3076  * tipc_socket_init - initialize TIPC socket interface
3077  *
3078  * Returns 0 on success, errno otherwise
3079  */
3080 int tipc_socket_init(void)
3081 {
3082 	int res;
3083 
3084 	res = proto_register(&tipc_proto, 1);
3085 	if (res) {
3086 		pr_err("Failed to register TIPC protocol type\n");
3087 		goto out;
3088 	}
3089 
3090 	res = sock_register(&tipc_family_ops);
3091 	if (res) {
3092 		pr_err("Failed to register TIPC socket type\n");
3093 		proto_unregister(&tipc_proto);
3094 		goto out;
3095 	}
3096  out:
3097 	return res;
3098 }
3099 
3100 /**
3101  * tipc_socket_stop - stop TIPC socket interface
3102  */
3103 void tipc_socket_stop(void)
3104 {
3105 	sock_unregister(tipc_family_ops.family);
3106 	proto_unregister(&tipc_proto);
3107 }
3108 
3109 /* Caller should hold socket lock for the passed tipc socket. */
3110 static int __tipc_nl_add_sk_con(struct sk_buff *skb, struct tipc_sock *tsk)
3111 {
3112 	u32 peer_node;
3113 	u32 peer_port;
3114 	struct nlattr *nest;
3115 
3116 	peer_node = tsk_peer_node(tsk);
3117 	peer_port = tsk_peer_port(tsk);
3118 
3119 	nest = nla_nest_start(skb, TIPC_NLA_SOCK_CON);
3120 
3121 	if (nla_put_u32(skb, TIPC_NLA_CON_NODE, peer_node))
3122 		goto msg_full;
3123 	if (nla_put_u32(skb, TIPC_NLA_CON_SOCK, peer_port))
3124 		goto msg_full;
3125 
3126 	if (tsk->conn_type != 0) {
3127 		if (nla_put_flag(skb, TIPC_NLA_CON_FLAG))
3128 			goto msg_full;
3129 		if (nla_put_u32(skb, TIPC_NLA_CON_TYPE, tsk->conn_type))
3130 			goto msg_full;
3131 		if (nla_put_u32(skb, TIPC_NLA_CON_INST, tsk->conn_instance))
3132 			goto msg_full;
3133 	}
3134 	nla_nest_end(skb, nest);
3135 
3136 	return 0;
3137 
3138 msg_full:
3139 	nla_nest_cancel(skb, nest);
3140 
3141 	return -EMSGSIZE;
3142 }
3143 
3144 /* Caller should hold socket lock for the passed tipc socket. */
3145 static int __tipc_nl_add_sk(struct sk_buff *skb, struct netlink_callback *cb,
3146 			    struct tipc_sock *tsk)
3147 {
3148 	int err;
3149 	void *hdr;
3150 	struct nlattr *attrs;
3151 	struct net *net = sock_net(skb->sk);
3152 	struct tipc_net *tn = net_generic(net, tipc_net_id);
3153 	struct sock *sk = &tsk->sk;
3154 
3155 	hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
3156 			  &tipc_genl_family, NLM_F_MULTI, TIPC_NL_SOCK_GET);
3157 	if (!hdr)
3158 		goto msg_cancel;
3159 
3160 	attrs = nla_nest_start(skb, TIPC_NLA_SOCK);
3161 	if (!attrs)
3162 		goto genlmsg_cancel;
3163 	if (nla_put_u32(skb, TIPC_NLA_SOCK_REF, tsk->portid))
3164 		goto attr_msg_cancel;
3165 	if (nla_put_u32(skb, TIPC_NLA_SOCK_ADDR, tn->own_addr))
3166 		goto attr_msg_cancel;
3167 
3168 	if (tipc_sk_connected(sk)) {
3169 		err = __tipc_nl_add_sk_con(skb, tsk);
3170 		if (err)
3171 			goto attr_msg_cancel;
3172 	} else if (!list_empty(&tsk->publications)) {
3173 		if (nla_put_flag(skb, TIPC_NLA_SOCK_HAS_PUBL))
3174 			goto attr_msg_cancel;
3175 	}
3176 	nla_nest_end(skb, attrs);
3177 	genlmsg_end(skb, hdr);
3178 
3179 	return 0;
3180 
3181 attr_msg_cancel:
3182 	nla_nest_cancel(skb, attrs);
3183 genlmsg_cancel:
3184 	genlmsg_cancel(skb, hdr);
3185 msg_cancel:
3186 	return -EMSGSIZE;
3187 }
3188 
3189 int tipc_nl_sk_dump(struct sk_buff *skb, struct netlink_callback *cb)
3190 {
3191 	int err;
3192 	struct tipc_sock *tsk;
3193 	const struct bucket_table *tbl;
3194 	struct rhash_head *pos;
3195 	struct net *net = sock_net(skb->sk);
3196 	struct tipc_net *tn = net_generic(net, tipc_net_id);
3197 	u32 tbl_id = cb->args[0];
3198 	u32 prev_portid = cb->args[1];
3199 
3200 	rcu_read_lock();
3201 	tbl = rht_dereference_rcu((&tn->sk_rht)->tbl, &tn->sk_rht);
3202 	for (; tbl_id < tbl->size; tbl_id++) {
3203 		rht_for_each_entry_rcu(tsk, pos, tbl, tbl_id, node) {
3204 			spin_lock_bh(&tsk->sk.sk_lock.slock);
3205 			if (prev_portid && prev_portid != tsk->portid) {
3206 				spin_unlock_bh(&tsk->sk.sk_lock.slock);
3207 				continue;
3208 			}
3209 
3210 			err = __tipc_nl_add_sk(skb, cb, tsk);
3211 			if (err) {
3212 				prev_portid = tsk->portid;
3213 				spin_unlock_bh(&tsk->sk.sk_lock.slock);
3214 				goto out;
3215 			}
3216 			prev_portid = 0;
3217 			spin_unlock_bh(&tsk->sk.sk_lock.slock);
3218 		}
3219 	}
3220 out:
3221 	rcu_read_unlock();
3222 	cb->args[0] = tbl_id;
3223 	cb->args[1] = prev_portid;
3224 
3225 	return skb->len;
3226 }
3227 
3228 /* Caller should hold socket lock for the passed tipc socket. */
3229 static int __tipc_nl_add_sk_publ(struct sk_buff *skb,
3230 				 struct netlink_callback *cb,
3231 				 struct publication *publ)
3232 {
3233 	void *hdr;
3234 	struct nlattr *attrs;
3235 
3236 	hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
3237 			  &tipc_genl_family, NLM_F_MULTI, TIPC_NL_PUBL_GET);
3238 	if (!hdr)
3239 		goto msg_cancel;
3240 
3241 	attrs = nla_nest_start(skb, TIPC_NLA_PUBL);
3242 	if (!attrs)
3243 		goto genlmsg_cancel;
3244 
3245 	if (nla_put_u32(skb, TIPC_NLA_PUBL_KEY, publ->key))
3246 		goto attr_msg_cancel;
3247 	if (nla_put_u32(skb, TIPC_NLA_PUBL_TYPE, publ->type))
3248 		goto attr_msg_cancel;
3249 	if (nla_put_u32(skb, TIPC_NLA_PUBL_LOWER, publ->lower))
3250 		goto attr_msg_cancel;
3251 	if (nla_put_u32(skb, TIPC_NLA_PUBL_UPPER, publ->upper))
3252 		goto attr_msg_cancel;
3253 
3254 	nla_nest_end(skb, attrs);
3255 	genlmsg_end(skb, hdr);
3256 
3257 	return 0;
3258 
3259 attr_msg_cancel:
3260 	nla_nest_cancel(skb, attrs);
3261 genlmsg_cancel:
3262 	genlmsg_cancel(skb, hdr);
3263 msg_cancel:
3264 	return -EMSGSIZE;
3265 }
3266 
3267 /* Caller should hold socket lock for the passed tipc socket. */
3268 static int __tipc_nl_list_sk_publ(struct sk_buff *skb,
3269 				  struct netlink_callback *cb,
3270 				  struct tipc_sock *tsk, u32 *last_publ)
3271 {
3272 	int err;
3273 	struct publication *p;
3274 
3275 	if (*last_publ) {
3276 		list_for_each_entry(p, &tsk->publications, pport_list) {
3277 			if (p->key == *last_publ)
3278 				break;
3279 		}
3280 		if (p->key != *last_publ) {
3281 			/* We never set seq or call nl_dump_check_consistent()
3282 			 * this means that setting prev_seq here will cause the
3283 			 * consistence check to fail in the netlink callback
3284 			 * handler. Resulting in the last NLMSG_DONE message
3285 			 * having the NLM_F_DUMP_INTR flag set.
3286 			 */
3287 			cb->prev_seq = 1;
3288 			*last_publ = 0;
3289 			return -EPIPE;
3290 		}
3291 	} else {
3292 		p = list_first_entry(&tsk->publications, struct publication,
3293 				     pport_list);
3294 	}
3295 
3296 	list_for_each_entry_from(p, &tsk->publications, pport_list) {
3297 		err = __tipc_nl_add_sk_publ(skb, cb, p);
3298 		if (err) {
3299 			*last_publ = p->key;
3300 			return err;
3301 		}
3302 	}
3303 	*last_publ = 0;
3304 
3305 	return 0;
3306 }
3307 
3308 int tipc_nl_publ_dump(struct sk_buff *skb, struct netlink_callback *cb)
3309 {
3310 	int err;
3311 	u32 tsk_portid = cb->args[0];
3312 	u32 last_publ = cb->args[1];
3313 	u32 done = cb->args[2];
3314 	struct net *net = sock_net(skb->sk);
3315 	struct tipc_sock *tsk;
3316 
3317 	if (!tsk_portid) {
3318 		struct nlattr **attrs;
3319 		struct nlattr *sock[TIPC_NLA_SOCK_MAX + 1];
3320 
3321 		err = tipc_nlmsg_parse(cb->nlh, &attrs);
3322 		if (err)
3323 			return err;
3324 
3325 		if (!attrs[TIPC_NLA_SOCK])
3326 			return -EINVAL;
3327 
3328 		err = nla_parse_nested(sock, TIPC_NLA_SOCK_MAX,
3329 				       attrs[TIPC_NLA_SOCK],
3330 				       tipc_nl_sock_policy, NULL);
3331 		if (err)
3332 			return err;
3333 
3334 		if (!sock[TIPC_NLA_SOCK_REF])
3335 			return -EINVAL;
3336 
3337 		tsk_portid = nla_get_u32(sock[TIPC_NLA_SOCK_REF]);
3338 	}
3339 
3340 	if (done)
3341 		return 0;
3342 
3343 	tsk = tipc_sk_lookup(net, tsk_portid);
3344 	if (!tsk)
3345 		return -EINVAL;
3346 
3347 	lock_sock(&tsk->sk);
3348 	err = __tipc_nl_list_sk_publ(skb, cb, tsk, &last_publ);
3349 	if (!err)
3350 		done = 1;
3351 	release_sock(&tsk->sk);
3352 	sock_put(&tsk->sk);
3353 
3354 	cb->args[0] = tsk_portid;
3355 	cb->args[1] = last_publ;
3356 	cb->args[2] = done;
3357 
3358 	return skb->len;
3359 }
3360