xref: /linux/net/rxrpc/af_rxrpc.c (revision 2b8232ce512105e28453f301d1510de8363bccd1)
1 /* AF_RXRPC implementation
2  *
3  * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
4  * Written by David Howells (dhowells@redhat.com)
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License
8  * as published by the Free Software Foundation; either version
9  * 2 of the License, or (at your option) any later version.
10  */
11 
12 #include <linux/module.h>
13 #include <linux/net.h>
14 #include <linux/skbuff.h>
15 #include <linux/poll.h>
16 #include <linux/proc_fs.h>
17 #include <net/net_namespace.h>
18 #include <net/sock.h>
19 #include <net/af_rxrpc.h>
20 #include "ar-internal.h"
21 
22 MODULE_DESCRIPTION("RxRPC network protocol");
23 MODULE_AUTHOR("Red Hat, Inc.");
24 MODULE_LICENSE("GPL");
25 MODULE_ALIAS_NETPROTO(PF_RXRPC);
26 
27 unsigned rxrpc_debug; // = RXRPC_DEBUG_KPROTO;
28 module_param_named(debug, rxrpc_debug, uint, S_IWUSR | S_IRUGO);
29 MODULE_PARM_DESC(rxrpc_debug, "RxRPC debugging mask");
30 
31 static int sysctl_rxrpc_max_qlen __read_mostly = 10;
32 
33 static struct proto rxrpc_proto;
34 static const struct proto_ops rxrpc_rpc_ops;
35 
36 /* local epoch for detecting local-end reset */
37 __be32 rxrpc_epoch;
38 
39 /* current debugging ID */
40 atomic_t rxrpc_debug_id;
41 
42 /* count of skbs currently in use */
43 atomic_t rxrpc_n_skbs;
44 
45 struct workqueue_struct *rxrpc_workqueue;
46 
47 static void rxrpc_sock_destructor(struct sock *);
48 
49 /*
50  * see if an RxRPC socket is currently writable
51  */
52 static inline int rxrpc_writable(struct sock *sk)
53 {
54 	return atomic_read(&sk->sk_wmem_alloc) < (size_t) sk->sk_sndbuf;
55 }
56 
57 /*
58  * wait for write bufferage to become available
59  */
60 static void rxrpc_write_space(struct sock *sk)
61 {
62 	_enter("%p", sk);
63 	read_lock(&sk->sk_callback_lock);
64 	if (rxrpc_writable(sk)) {
65 		if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
66 			wake_up_interruptible(sk->sk_sleep);
67 		sk_wake_async(sk, 2, POLL_OUT);
68 	}
69 	read_unlock(&sk->sk_callback_lock);
70 }
71 
72 /*
73  * validate an RxRPC address
74  */
75 static int rxrpc_validate_address(struct rxrpc_sock *rx,
76 				  struct sockaddr_rxrpc *srx,
77 				  int len)
78 {
79 	if (len < sizeof(struct sockaddr_rxrpc))
80 		return -EINVAL;
81 
82 	if (srx->srx_family != AF_RXRPC)
83 		return -EAFNOSUPPORT;
84 
85 	if (srx->transport_type != SOCK_DGRAM)
86 		return -ESOCKTNOSUPPORT;
87 
88 	len -= offsetof(struct sockaddr_rxrpc, transport);
89 	if (srx->transport_len < sizeof(sa_family_t) ||
90 	    srx->transport_len > len)
91 		return -EINVAL;
92 
93 	if (srx->transport.family != rx->proto)
94 		return -EAFNOSUPPORT;
95 
96 	switch (srx->transport.family) {
97 	case AF_INET:
98 		_debug("INET: %x @ %u.%u.%u.%u",
99 		       ntohs(srx->transport.sin.sin_port),
100 		       NIPQUAD(srx->transport.sin.sin_addr));
101 		if (srx->transport_len > 8)
102 			memset((void *)&srx->transport + 8, 0,
103 			       srx->transport_len - 8);
104 		break;
105 
106 	case AF_INET6:
107 	default:
108 		return -EAFNOSUPPORT;
109 	}
110 
111 	return 0;
112 }
113 
114 /*
115  * bind a local address to an RxRPC socket
116  */
117 static int rxrpc_bind(struct socket *sock, struct sockaddr *saddr, int len)
118 {
119 	struct sockaddr_rxrpc *srx = (struct sockaddr_rxrpc *) saddr;
120 	struct sock *sk = sock->sk;
121 	struct rxrpc_local *local;
122 	struct rxrpc_sock *rx = rxrpc_sk(sk), *prx;
123 	__be16 service_id;
124 	int ret;
125 
126 	_enter("%p,%p,%d", rx, saddr, len);
127 
128 	ret = rxrpc_validate_address(rx, srx, len);
129 	if (ret < 0)
130 		goto error;
131 
132 	lock_sock(&rx->sk);
133 
134 	if (rx->sk.sk_state != RXRPC_UNCONNECTED) {
135 		ret = -EINVAL;
136 		goto error_unlock;
137 	}
138 
139 	memcpy(&rx->srx, srx, sizeof(rx->srx));
140 
141 	/* find a local transport endpoint if we don't have one already */
142 	local = rxrpc_lookup_local(&rx->srx);
143 	if (IS_ERR(local)) {
144 		ret = PTR_ERR(local);
145 		goto error_unlock;
146 	}
147 
148 	rx->local = local;
149 	if (srx->srx_service) {
150 		service_id = htons(srx->srx_service);
151 		write_lock_bh(&local->services_lock);
152 		list_for_each_entry(prx, &local->services, listen_link) {
153 			if (prx->service_id == service_id)
154 				goto service_in_use;
155 		}
156 
157 		rx->service_id = service_id;
158 		list_add_tail(&rx->listen_link, &local->services);
159 		write_unlock_bh(&local->services_lock);
160 
161 		rx->sk.sk_state = RXRPC_SERVER_BOUND;
162 	} else {
163 		rx->sk.sk_state = RXRPC_CLIENT_BOUND;
164 	}
165 
166 	release_sock(&rx->sk);
167 	_leave(" = 0");
168 	return 0;
169 
170 service_in_use:
171 	ret = -EADDRINUSE;
172 	write_unlock_bh(&local->services_lock);
173 error_unlock:
174 	release_sock(&rx->sk);
175 error:
176 	_leave(" = %d", ret);
177 	return ret;
178 }
179 
180 /*
181  * set the number of pending calls permitted on a listening socket
182  */
183 static int rxrpc_listen(struct socket *sock, int backlog)
184 {
185 	struct sock *sk = sock->sk;
186 	struct rxrpc_sock *rx = rxrpc_sk(sk);
187 	int ret;
188 
189 	_enter("%p,%d", rx, backlog);
190 
191 	lock_sock(&rx->sk);
192 
193 	switch (rx->sk.sk_state) {
194 	case RXRPC_UNCONNECTED:
195 		ret = -EADDRNOTAVAIL;
196 		break;
197 	case RXRPC_CLIENT_BOUND:
198 	case RXRPC_CLIENT_CONNECTED:
199 	default:
200 		ret = -EBUSY;
201 		break;
202 	case RXRPC_SERVER_BOUND:
203 		ASSERT(rx->local != NULL);
204 		sk->sk_max_ack_backlog = backlog;
205 		rx->sk.sk_state = RXRPC_SERVER_LISTENING;
206 		ret = 0;
207 		break;
208 	}
209 
210 	release_sock(&rx->sk);
211 	_leave(" = %d", ret);
212 	return ret;
213 }
214 
215 /*
216  * find a transport by address
217  */
218 static struct rxrpc_transport *rxrpc_name_to_transport(struct socket *sock,
219 						       struct sockaddr *addr,
220 						       int addr_len, int flags,
221 						       gfp_t gfp)
222 {
223 	struct sockaddr_rxrpc *srx = (struct sockaddr_rxrpc *) addr;
224 	struct rxrpc_transport *trans;
225 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
226 	struct rxrpc_peer *peer;
227 
228 	_enter("%p,%p,%d,%d", rx, addr, addr_len, flags);
229 
230 	ASSERT(rx->local != NULL);
231 	ASSERT(rx->sk.sk_state > RXRPC_UNCONNECTED);
232 
233 	if (rx->srx.transport_type != srx->transport_type)
234 		return ERR_PTR(-ESOCKTNOSUPPORT);
235 	if (rx->srx.transport.family != srx->transport.family)
236 		return ERR_PTR(-EAFNOSUPPORT);
237 
238 	/* find a remote transport endpoint from the local one */
239 	peer = rxrpc_get_peer(srx, gfp);
240 	if (IS_ERR(peer))
241 		return ERR_PTR(PTR_ERR(peer));
242 
243 	/* find a transport */
244 	trans = rxrpc_get_transport(rx->local, peer, gfp);
245 	rxrpc_put_peer(peer);
246 	_leave(" = %p", trans);
247 	return trans;
248 }
249 
250 /**
251  * rxrpc_kernel_begin_call - Allow a kernel service to begin a call
252  * @sock: The socket on which to make the call
253  * @srx: The address of the peer to contact (defaults to socket setting)
254  * @key: The security context to use (defaults to socket setting)
255  * @user_call_ID: The ID to use
256  *
257  * Allow a kernel service to begin a call on the nominated socket.  This just
258  * sets up all the internal tracking structures and allocates connection and
259  * call IDs as appropriate.  The call to be used is returned.
260  *
261  * The default socket destination address and security may be overridden by
262  * supplying @srx and @key.
263  */
264 struct rxrpc_call *rxrpc_kernel_begin_call(struct socket *sock,
265 					   struct sockaddr_rxrpc *srx,
266 					   struct key *key,
267 					   unsigned long user_call_ID,
268 					   gfp_t gfp)
269 {
270 	struct rxrpc_conn_bundle *bundle;
271 	struct rxrpc_transport *trans;
272 	struct rxrpc_call *call;
273 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
274 	__be16 service_id;
275 
276 	_enter(",,%x,%lx", key_serial(key), user_call_ID);
277 
278 	lock_sock(&rx->sk);
279 
280 	if (srx) {
281 		trans = rxrpc_name_to_transport(sock, (struct sockaddr *) srx,
282 						sizeof(*srx), 0, gfp);
283 		if (IS_ERR(trans)) {
284 			call = ERR_PTR(PTR_ERR(trans));
285 			trans = NULL;
286 			goto out;
287 		}
288 	} else {
289 		trans = rx->trans;
290 		if (!trans) {
291 			call = ERR_PTR(-ENOTCONN);
292 			goto out;
293 		}
294 		atomic_inc(&trans->usage);
295 	}
296 
297 	service_id = rx->service_id;
298 	if (srx)
299 		service_id = htons(srx->srx_service);
300 
301 	if (!key)
302 		key = rx->key;
303 	if (key && !key->payload.data)
304 		key = NULL; /* a no-security key */
305 
306 	bundle = rxrpc_get_bundle(rx, trans, key, service_id, gfp);
307 	if (IS_ERR(bundle)) {
308 		call = ERR_PTR(PTR_ERR(bundle));
309 		goto out;
310 	}
311 
312 	call = rxrpc_get_client_call(rx, trans, bundle, user_call_ID, true,
313 				     gfp);
314 	rxrpc_put_bundle(trans, bundle);
315 out:
316 	rxrpc_put_transport(trans);
317 	release_sock(&rx->sk);
318 	_leave(" = %p", call);
319 	return call;
320 }
321 
322 EXPORT_SYMBOL(rxrpc_kernel_begin_call);
323 
324 /**
325  * rxrpc_kernel_end_call - Allow a kernel service to end a call it was using
326  * @call: The call to end
327  *
328  * Allow a kernel service to end a call it was using.  The call must be
329  * complete before this is called (the call should be aborted if necessary).
330  */
331 void rxrpc_kernel_end_call(struct rxrpc_call *call)
332 {
333 	_enter("%d{%d}", call->debug_id, atomic_read(&call->usage));
334 	rxrpc_remove_user_ID(call->socket, call);
335 	rxrpc_put_call(call);
336 }
337 
338 EXPORT_SYMBOL(rxrpc_kernel_end_call);
339 
340 /**
341  * rxrpc_kernel_intercept_rx_messages - Intercept received RxRPC messages
342  * @sock: The socket to intercept received messages on
343  * @interceptor: The function to pass the messages to
344  *
345  * Allow a kernel service to intercept messages heading for the Rx queue on an
346  * RxRPC socket.  They get passed to the specified function instead.
347  * @interceptor should free the socket buffers it is given.  @interceptor is
348  * called with the socket receive queue spinlock held and softirqs disabled -
349  * this ensures that the messages will be delivered in the right order.
350  */
351 void rxrpc_kernel_intercept_rx_messages(struct socket *sock,
352 					rxrpc_interceptor_t interceptor)
353 {
354 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
355 
356 	_enter("");
357 	rx->interceptor = interceptor;
358 }
359 
360 EXPORT_SYMBOL(rxrpc_kernel_intercept_rx_messages);
361 
362 /*
363  * connect an RxRPC socket
364  * - this just targets it at a specific destination; no actual connection
365  *   negotiation takes place
366  */
367 static int rxrpc_connect(struct socket *sock, struct sockaddr *addr,
368 			 int addr_len, int flags)
369 {
370 	struct sockaddr_rxrpc *srx = (struct sockaddr_rxrpc *) addr;
371 	struct sock *sk = sock->sk;
372 	struct rxrpc_transport *trans;
373 	struct rxrpc_local *local;
374 	struct rxrpc_sock *rx = rxrpc_sk(sk);
375 	int ret;
376 
377 	_enter("%p,%p,%d,%d", rx, addr, addr_len, flags);
378 
379 	ret = rxrpc_validate_address(rx, srx, addr_len);
380 	if (ret < 0) {
381 		_leave(" = %d [bad addr]", ret);
382 		return ret;
383 	}
384 
385 	lock_sock(&rx->sk);
386 
387 	switch (rx->sk.sk_state) {
388 	case RXRPC_UNCONNECTED:
389 		/* find a local transport endpoint if we don't have one already */
390 		ASSERTCMP(rx->local, ==, NULL);
391 		rx->srx.srx_family = AF_RXRPC;
392 		rx->srx.srx_service = 0;
393 		rx->srx.transport_type = srx->transport_type;
394 		rx->srx.transport_len = sizeof(sa_family_t);
395 		rx->srx.transport.family = srx->transport.family;
396 		local = rxrpc_lookup_local(&rx->srx);
397 		if (IS_ERR(local)) {
398 			release_sock(&rx->sk);
399 			return PTR_ERR(local);
400 		}
401 		rx->local = local;
402 		rx->sk.sk_state = RXRPC_CLIENT_BOUND;
403 	case RXRPC_CLIENT_BOUND:
404 		break;
405 	case RXRPC_CLIENT_CONNECTED:
406 		release_sock(&rx->sk);
407 		return -EISCONN;
408 	default:
409 		release_sock(&rx->sk);
410 		return -EBUSY; /* server sockets can't connect as well */
411 	}
412 
413 	trans = rxrpc_name_to_transport(sock, addr, addr_len, flags,
414 					GFP_KERNEL);
415 	if (IS_ERR(trans)) {
416 		release_sock(&rx->sk);
417 		_leave(" = %ld", PTR_ERR(trans));
418 		return PTR_ERR(trans);
419 	}
420 
421 	rx->trans = trans;
422 	rx->service_id = htons(srx->srx_service);
423 	rx->sk.sk_state = RXRPC_CLIENT_CONNECTED;
424 
425 	release_sock(&rx->sk);
426 	return 0;
427 }
428 
429 /*
430  * send a message through an RxRPC socket
431  * - in a client this does a number of things:
432  *   - finds/sets up a connection for the security specified (if any)
433  *   - initiates a call (ID in control data)
434  *   - ends the request phase of a call (if MSG_MORE is not set)
435  *   - sends a call data packet
436  *   - may send an abort (abort code in control data)
437  */
438 static int rxrpc_sendmsg(struct kiocb *iocb, struct socket *sock,
439 			 struct msghdr *m, size_t len)
440 {
441 	struct rxrpc_transport *trans;
442 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
443 	int ret;
444 
445 	_enter(",{%d},,%zu", rx->sk.sk_state, len);
446 
447 	if (m->msg_flags & MSG_OOB)
448 		return -EOPNOTSUPP;
449 
450 	if (m->msg_name) {
451 		ret = rxrpc_validate_address(rx, m->msg_name, m->msg_namelen);
452 		if (ret < 0) {
453 			_leave(" = %d [bad addr]", ret);
454 			return ret;
455 		}
456 	}
457 
458 	trans = NULL;
459 	lock_sock(&rx->sk);
460 
461 	if (m->msg_name) {
462 		ret = -EISCONN;
463 		trans = rxrpc_name_to_transport(sock, m->msg_name,
464 						m->msg_namelen, 0, GFP_KERNEL);
465 		if (IS_ERR(trans)) {
466 			ret = PTR_ERR(trans);
467 			trans = NULL;
468 			goto out;
469 		}
470 	} else {
471 		trans = rx->trans;
472 		if (trans)
473 			atomic_inc(&trans->usage);
474 	}
475 
476 	switch (rx->sk.sk_state) {
477 	case RXRPC_SERVER_LISTENING:
478 		if (!m->msg_name) {
479 			ret = rxrpc_server_sendmsg(iocb, rx, m, len);
480 			break;
481 		}
482 	case RXRPC_SERVER_BOUND:
483 	case RXRPC_CLIENT_BOUND:
484 		if (!m->msg_name) {
485 			ret = -ENOTCONN;
486 			break;
487 		}
488 	case RXRPC_CLIENT_CONNECTED:
489 		ret = rxrpc_client_sendmsg(iocb, rx, trans, m, len);
490 		break;
491 	default:
492 		ret = -ENOTCONN;
493 		break;
494 	}
495 
496 out:
497 	release_sock(&rx->sk);
498 	if (trans)
499 		rxrpc_put_transport(trans);
500 	_leave(" = %d", ret);
501 	return ret;
502 }
503 
504 /*
505  * set RxRPC socket options
506  */
507 static int rxrpc_setsockopt(struct socket *sock, int level, int optname,
508 			    char __user *optval, int optlen)
509 {
510 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
511 	unsigned min_sec_level;
512 	int ret;
513 
514 	_enter(",%d,%d,,%d", level, optname, optlen);
515 
516 	lock_sock(&rx->sk);
517 	ret = -EOPNOTSUPP;
518 
519 	if (level == SOL_RXRPC) {
520 		switch (optname) {
521 		case RXRPC_EXCLUSIVE_CONNECTION:
522 			ret = -EINVAL;
523 			if (optlen != 0)
524 				goto error;
525 			ret = -EISCONN;
526 			if (rx->sk.sk_state != RXRPC_UNCONNECTED)
527 				goto error;
528 			set_bit(RXRPC_SOCK_EXCLUSIVE_CONN, &rx->flags);
529 			goto success;
530 
531 		case RXRPC_SECURITY_KEY:
532 			ret = -EINVAL;
533 			if (rx->key)
534 				goto error;
535 			ret = -EISCONN;
536 			if (rx->sk.sk_state != RXRPC_UNCONNECTED)
537 				goto error;
538 			ret = rxrpc_request_key(rx, optval, optlen);
539 			goto error;
540 
541 		case RXRPC_SECURITY_KEYRING:
542 			ret = -EINVAL;
543 			if (rx->key)
544 				goto error;
545 			ret = -EISCONN;
546 			if (rx->sk.sk_state != RXRPC_UNCONNECTED)
547 				goto error;
548 			ret = rxrpc_server_keyring(rx, optval, optlen);
549 			goto error;
550 
551 		case RXRPC_MIN_SECURITY_LEVEL:
552 			ret = -EINVAL;
553 			if (optlen != sizeof(unsigned))
554 				goto error;
555 			ret = -EISCONN;
556 			if (rx->sk.sk_state != RXRPC_UNCONNECTED)
557 				goto error;
558 			ret = get_user(min_sec_level,
559 				       (unsigned __user *) optval);
560 			if (ret < 0)
561 				goto error;
562 			ret = -EINVAL;
563 			if (min_sec_level > RXRPC_SECURITY_MAX)
564 				goto error;
565 			rx->min_sec_level = min_sec_level;
566 			goto success;
567 
568 		default:
569 			break;
570 		}
571 	}
572 
573 success:
574 	ret = 0;
575 error:
576 	release_sock(&rx->sk);
577 	return ret;
578 }
579 
580 /*
581  * permit an RxRPC socket to be polled
582  */
583 static unsigned int rxrpc_poll(struct file *file, struct socket *sock,
584 			       poll_table *wait)
585 {
586 	unsigned int mask;
587 	struct sock *sk = sock->sk;
588 
589 	poll_wait(file, sk->sk_sleep, wait);
590 	mask = 0;
591 
592 	/* the socket is readable if there are any messages waiting on the Rx
593 	 * queue */
594 	if (!skb_queue_empty(&sk->sk_receive_queue))
595 		mask |= POLLIN | POLLRDNORM;
596 
597 	/* the socket is writable if there is space to add new data to the
598 	 * socket; there is no guarantee that any particular call in progress
599 	 * on the socket may have space in the Tx ACK window */
600 	if (rxrpc_writable(sk))
601 		mask |= POLLOUT | POLLWRNORM;
602 
603 	return mask;
604 }
605 
606 /*
607  * create an RxRPC socket
608  */
609 static int rxrpc_create(struct net *net, struct socket *sock, int protocol)
610 {
611 	struct rxrpc_sock *rx;
612 	struct sock *sk;
613 
614 	_enter("%p,%d", sock, protocol);
615 
616 	if (net != &init_net)
617 		return -EAFNOSUPPORT;
618 
619 	/* we support transport protocol UDP only */
620 	if (protocol != PF_INET)
621 		return -EPROTONOSUPPORT;
622 
623 	if (sock->type != SOCK_DGRAM)
624 		return -ESOCKTNOSUPPORT;
625 
626 	sock->ops = &rxrpc_rpc_ops;
627 	sock->state = SS_UNCONNECTED;
628 
629 	sk = sk_alloc(net, PF_RXRPC, GFP_KERNEL, &rxrpc_proto, 1);
630 	if (!sk)
631 		return -ENOMEM;
632 
633 	sock_init_data(sock, sk);
634 	sk->sk_state		= RXRPC_UNCONNECTED;
635 	sk->sk_write_space	= rxrpc_write_space;
636 	sk->sk_max_ack_backlog	= sysctl_rxrpc_max_qlen;
637 	sk->sk_destruct		= rxrpc_sock_destructor;
638 
639 	rx = rxrpc_sk(sk);
640 	rx->proto = protocol;
641 	rx->calls = RB_ROOT;
642 
643 	INIT_LIST_HEAD(&rx->listen_link);
644 	INIT_LIST_HEAD(&rx->secureq);
645 	INIT_LIST_HEAD(&rx->acceptq);
646 	rwlock_init(&rx->call_lock);
647 	memset(&rx->srx, 0, sizeof(rx->srx));
648 
649 	_leave(" = 0 [%p]", rx);
650 	return 0;
651 }
652 
653 /*
654  * RxRPC socket destructor
655  */
656 static void rxrpc_sock_destructor(struct sock *sk)
657 {
658 	_enter("%p", sk);
659 
660 	rxrpc_purge_queue(&sk->sk_receive_queue);
661 
662 	BUG_TRAP(!atomic_read(&sk->sk_wmem_alloc));
663 	BUG_TRAP(sk_unhashed(sk));
664 	BUG_TRAP(!sk->sk_socket);
665 
666 	if (!sock_flag(sk, SOCK_DEAD)) {
667 		printk("Attempt to release alive rxrpc socket: %p\n", sk);
668 		return;
669 	}
670 }
671 
672 /*
673  * release an RxRPC socket
674  */
675 static int rxrpc_release_sock(struct sock *sk)
676 {
677 	struct rxrpc_sock *rx = rxrpc_sk(sk);
678 
679 	_enter("%p{%d,%d}", sk, sk->sk_state, atomic_read(&sk->sk_refcnt));
680 
681 	/* declare the socket closed for business */
682 	sock_orphan(sk);
683 	sk->sk_shutdown = SHUTDOWN_MASK;
684 
685 	spin_lock_bh(&sk->sk_receive_queue.lock);
686 	sk->sk_state = RXRPC_CLOSE;
687 	spin_unlock_bh(&sk->sk_receive_queue.lock);
688 
689 	ASSERTCMP(rx->listen_link.next, !=, LIST_POISON1);
690 
691 	if (!list_empty(&rx->listen_link)) {
692 		write_lock_bh(&rx->local->services_lock);
693 		list_del(&rx->listen_link);
694 		write_unlock_bh(&rx->local->services_lock);
695 	}
696 
697 	/* try to flush out this socket */
698 	rxrpc_release_calls_on_socket(rx);
699 	flush_workqueue(rxrpc_workqueue);
700 	rxrpc_purge_queue(&sk->sk_receive_queue);
701 
702 	if (rx->conn) {
703 		rxrpc_put_connection(rx->conn);
704 		rx->conn = NULL;
705 	}
706 
707 	if (rx->bundle) {
708 		rxrpc_put_bundle(rx->trans, rx->bundle);
709 		rx->bundle = NULL;
710 	}
711 	if (rx->trans) {
712 		rxrpc_put_transport(rx->trans);
713 		rx->trans = NULL;
714 	}
715 	if (rx->local) {
716 		rxrpc_put_local(rx->local);
717 		rx->local = NULL;
718 	}
719 
720 	key_put(rx->key);
721 	rx->key = NULL;
722 	key_put(rx->securities);
723 	rx->securities = NULL;
724 	sock_put(sk);
725 
726 	_leave(" = 0");
727 	return 0;
728 }
729 
730 /*
731  * release an RxRPC BSD socket on close() or equivalent
732  */
733 static int rxrpc_release(struct socket *sock)
734 {
735 	struct sock *sk = sock->sk;
736 
737 	_enter("%p{%p}", sock, sk);
738 
739 	if (!sk)
740 		return 0;
741 
742 	sock->sk = NULL;
743 
744 	return rxrpc_release_sock(sk);
745 }
746 
747 /*
748  * RxRPC network protocol
749  */
750 static const struct proto_ops rxrpc_rpc_ops = {
751 	.family		= PF_UNIX,
752 	.owner		= THIS_MODULE,
753 	.release	= rxrpc_release,
754 	.bind		= rxrpc_bind,
755 	.connect	= rxrpc_connect,
756 	.socketpair	= sock_no_socketpair,
757 	.accept		= sock_no_accept,
758 	.getname	= sock_no_getname,
759 	.poll		= rxrpc_poll,
760 	.ioctl		= sock_no_ioctl,
761 	.listen		= rxrpc_listen,
762 	.shutdown	= sock_no_shutdown,
763 	.setsockopt	= rxrpc_setsockopt,
764 	.getsockopt	= sock_no_getsockopt,
765 	.sendmsg	= rxrpc_sendmsg,
766 	.recvmsg	= rxrpc_recvmsg,
767 	.mmap		= sock_no_mmap,
768 	.sendpage	= sock_no_sendpage,
769 };
770 
771 static struct proto rxrpc_proto = {
772 	.name		= "RXRPC",
773 	.owner		= THIS_MODULE,
774 	.obj_size	= sizeof(struct rxrpc_sock),
775 	.max_header	= sizeof(struct rxrpc_header),
776 };
777 
778 static struct net_proto_family rxrpc_family_ops = {
779 	.family	= PF_RXRPC,
780 	.create = rxrpc_create,
781 	.owner	= THIS_MODULE,
782 };
783 
784 /*
785  * initialise and register the RxRPC protocol
786  */
787 static int __init af_rxrpc_init(void)
788 {
789 	struct sk_buff *dummy_skb;
790 	int ret = -1;
791 
792 	BUILD_BUG_ON(sizeof(struct rxrpc_skb_priv) > sizeof(dummy_skb->cb));
793 
794 	rxrpc_epoch = htonl(get_seconds());
795 
796 	ret = -ENOMEM;
797 	rxrpc_call_jar = kmem_cache_create(
798 		"rxrpc_call_jar", sizeof(struct rxrpc_call), 0,
799 		SLAB_HWCACHE_ALIGN, NULL);
800 	if (!rxrpc_call_jar) {
801 		printk(KERN_NOTICE "RxRPC: Failed to allocate call jar\n");
802 		goto error_call_jar;
803 	}
804 
805 	rxrpc_workqueue = create_workqueue("krxrpcd");
806 	if (!rxrpc_workqueue) {
807 		printk(KERN_NOTICE "RxRPC: Failed to allocate work queue\n");
808 		goto error_work_queue;
809 	}
810 
811 	ret = proto_register(&rxrpc_proto, 1);
812 	if (ret < 0) {
813 		printk(KERN_CRIT "RxRPC: Cannot register protocol\n");
814 		goto error_proto;
815 	}
816 
817 	ret = sock_register(&rxrpc_family_ops);
818 	if (ret < 0) {
819 		printk(KERN_CRIT "RxRPC: Cannot register socket family\n");
820 		goto error_sock;
821 	}
822 
823 	ret = register_key_type(&key_type_rxrpc);
824 	if (ret < 0) {
825 		printk(KERN_CRIT "RxRPC: Cannot register client key type\n");
826 		goto error_key_type;
827 	}
828 
829 	ret = register_key_type(&key_type_rxrpc_s);
830 	if (ret < 0) {
831 		printk(KERN_CRIT "RxRPC: Cannot register server key type\n");
832 		goto error_key_type_s;
833 	}
834 
835 #ifdef CONFIG_PROC_FS
836 	proc_net_fops_create(&init_net, "rxrpc_calls", 0, &rxrpc_call_seq_fops);
837 	proc_net_fops_create(&init_net, "rxrpc_conns", 0, &rxrpc_connection_seq_fops);
838 #endif
839 	return 0;
840 
841 error_key_type_s:
842 	unregister_key_type(&key_type_rxrpc);
843 error_key_type:
844 	sock_unregister(PF_RXRPC);
845 error_sock:
846 	proto_unregister(&rxrpc_proto);
847 error_proto:
848 	destroy_workqueue(rxrpc_workqueue);
849 error_work_queue:
850 	kmem_cache_destroy(rxrpc_call_jar);
851 error_call_jar:
852 	return ret;
853 }
854 
855 /*
856  * unregister the RxRPC protocol
857  */
858 static void __exit af_rxrpc_exit(void)
859 {
860 	_enter("");
861 	unregister_key_type(&key_type_rxrpc_s);
862 	unregister_key_type(&key_type_rxrpc);
863 	sock_unregister(PF_RXRPC);
864 	proto_unregister(&rxrpc_proto);
865 	rxrpc_destroy_all_calls();
866 	rxrpc_destroy_all_connections();
867 	rxrpc_destroy_all_transports();
868 	rxrpc_destroy_all_peers();
869 	rxrpc_destroy_all_locals();
870 
871 	ASSERTCMP(atomic_read(&rxrpc_n_skbs), ==, 0);
872 
873 	_debug("flush scheduled work");
874 	flush_workqueue(rxrpc_workqueue);
875 	proc_net_remove(&init_net, "rxrpc_conns");
876 	proc_net_remove(&init_net, "rxrpc_calls");
877 	destroy_workqueue(rxrpc_workqueue);
878 	kmem_cache_destroy(rxrpc_call_jar);
879 	_leave("");
880 }
881 
882 module_init(af_rxrpc_init);
883 module_exit(af_rxrpc_exit);
884