xref: /openbmc/linux/net/rxrpc/af_rxrpc.c (revision 545e4006)
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 <linux/key-type.h>
18 #include <net/net_namespace.h>
19 #include <net/sock.h>
20 #include <net/af_rxrpc.h>
21 #include "ar-internal.h"
22 
23 MODULE_DESCRIPTION("RxRPC network protocol");
24 MODULE_AUTHOR("Red Hat, Inc.");
25 MODULE_LICENSE("GPL");
26 MODULE_ALIAS_NETPROTO(PF_RXRPC);
27 
28 unsigned rxrpc_debug; // = RXRPC_DEBUG_KPROTO;
29 module_param_named(debug, rxrpc_debug, uint, S_IWUSR | S_IRUGO);
30 MODULE_PARM_DESC(debug, "RxRPC debugging mask");
31 
32 static int sysctl_rxrpc_max_qlen __read_mostly = 10;
33 
34 static struct proto rxrpc_proto;
35 static const struct proto_ops rxrpc_rpc_ops;
36 
37 /* local epoch for detecting local-end reset */
38 __be32 rxrpc_epoch;
39 
40 /* current debugging ID */
41 atomic_t rxrpc_debug_id;
42 
43 /* count of skbs currently in use */
44 atomic_t rxrpc_n_skbs;
45 
46 struct workqueue_struct *rxrpc_workqueue;
47 
48 static void rxrpc_sock_destructor(struct sock *);
49 
50 /*
51  * see if an RxRPC socket is currently writable
52  */
53 static inline int rxrpc_writable(struct sock *sk)
54 {
55 	return atomic_read(&sk->sk_wmem_alloc) < (size_t) sk->sk_sndbuf;
56 }
57 
58 /*
59  * wait for write bufferage to become available
60  */
61 static void rxrpc_write_space(struct sock *sk)
62 {
63 	_enter("%p", sk);
64 	read_lock(&sk->sk_callback_lock);
65 	if (rxrpc_writable(sk)) {
66 		if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
67 			wake_up_interruptible(sk->sk_sleep);
68 		sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
69 	}
70 	read_unlock(&sk->sk_callback_lock);
71 }
72 
73 /*
74  * validate an RxRPC address
75  */
76 static int rxrpc_validate_address(struct rxrpc_sock *rx,
77 				  struct sockaddr_rxrpc *srx,
78 				  int len)
79 {
80 	if (len < sizeof(struct sockaddr_rxrpc))
81 		return -EINVAL;
82 
83 	if (srx->srx_family != AF_RXRPC)
84 		return -EAFNOSUPPORT;
85 
86 	if (srx->transport_type != SOCK_DGRAM)
87 		return -ESOCKTNOSUPPORT;
88 
89 	len -= offsetof(struct sockaddr_rxrpc, transport);
90 	if (srx->transport_len < sizeof(sa_family_t) ||
91 	    srx->transport_len > len)
92 		return -EINVAL;
93 
94 	if (srx->transport.family != rx->proto)
95 		return -EAFNOSUPPORT;
96 
97 	switch (srx->transport.family) {
98 	case AF_INET:
99 		_debug("INET: %x @ %u.%u.%u.%u",
100 		       ntohs(srx->transport.sin.sin_port),
101 		       NIPQUAD(srx->transport.sin.sin_addr));
102 		if (srx->transport_len > 8)
103 			memset((void *)&srx->transport + 8, 0,
104 			       srx->transport_len - 8);
105 		break;
106 
107 	case AF_INET6:
108 	default:
109 		return -EAFNOSUPPORT;
110 	}
111 
112 	return 0;
113 }
114 
115 /*
116  * bind a local address to an RxRPC socket
117  */
118 static int rxrpc_bind(struct socket *sock, struct sockaddr *saddr, int len)
119 {
120 	struct sockaddr_rxrpc *srx = (struct sockaddr_rxrpc *) saddr;
121 	struct sock *sk = sock->sk;
122 	struct rxrpc_local *local;
123 	struct rxrpc_sock *rx = rxrpc_sk(sk), *prx;
124 	__be16 service_id;
125 	int ret;
126 
127 	_enter("%p,%p,%d", rx, saddr, len);
128 
129 	ret = rxrpc_validate_address(rx, srx, len);
130 	if (ret < 0)
131 		goto error;
132 
133 	lock_sock(&rx->sk);
134 
135 	if (rx->sk.sk_state != RXRPC_UNCONNECTED) {
136 		ret = -EINVAL;
137 		goto error_unlock;
138 	}
139 
140 	memcpy(&rx->srx, srx, sizeof(rx->srx));
141 
142 	/* find a local transport endpoint if we don't have one already */
143 	local = rxrpc_lookup_local(&rx->srx);
144 	if (IS_ERR(local)) {
145 		ret = PTR_ERR(local);
146 		goto error_unlock;
147 	}
148 
149 	rx->local = local;
150 	if (srx->srx_service) {
151 		service_id = htons(srx->srx_service);
152 		write_lock_bh(&local->services_lock);
153 		list_for_each_entry(prx, &local->services, listen_link) {
154 			if (prx->service_id == service_id)
155 				goto service_in_use;
156 		}
157 
158 		rx->service_id = service_id;
159 		list_add_tail(&rx->listen_link, &local->services);
160 		write_unlock_bh(&local->services_lock);
161 
162 		rx->sk.sk_state = RXRPC_SERVER_BOUND;
163 	} else {
164 		rx->sk.sk_state = RXRPC_CLIENT_BOUND;
165 	}
166 
167 	release_sock(&rx->sk);
168 	_leave(" = 0");
169 	return 0;
170 
171 service_in_use:
172 	ret = -EADDRINUSE;
173 	write_unlock_bh(&local->services_lock);
174 error_unlock:
175 	release_sock(&rx->sk);
176 error:
177 	_leave(" = %d", ret);
178 	return ret;
179 }
180 
181 /*
182  * set the number of pending calls permitted on a listening socket
183  */
184 static int rxrpc_listen(struct socket *sock, int backlog)
185 {
186 	struct sock *sk = sock->sk;
187 	struct rxrpc_sock *rx = rxrpc_sk(sk);
188 	int ret;
189 
190 	_enter("%p,%d", rx, backlog);
191 
192 	lock_sock(&rx->sk);
193 
194 	switch (rx->sk.sk_state) {
195 	case RXRPC_UNCONNECTED:
196 		ret = -EADDRNOTAVAIL;
197 		break;
198 	case RXRPC_CLIENT_BOUND:
199 	case RXRPC_CLIENT_CONNECTED:
200 	default:
201 		ret = -EBUSY;
202 		break;
203 	case RXRPC_SERVER_BOUND:
204 		ASSERT(rx->local != NULL);
205 		sk->sk_max_ack_backlog = backlog;
206 		rx->sk.sk_state = RXRPC_SERVER_LISTENING;
207 		ret = 0;
208 		break;
209 	}
210 
211 	release_sock(&rx->sk);
212 	_leave(" = %d", ret);
213 	return ret;
214 }
215 
216 /*
217  * find a transport by address
218  */
219 static struct rxrpc_transport *rxrpc_name_to_transport(struct socket *sock,
220 						       struct sockaddr *addr,
221 						       int addr_len, int flags,
222 						       gfp_t gfp)
223 {
224 	struct sockaddr_rxrpc *srx = (struct sockaddr_rxrpc *) addr;
225 	struct rxrpc_transport *trans;
226 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
227 	struct rxrpc_peer *peer;
228 
229 	_enter("%p,%p,%d,%d", rx, addr, addr_len, flags);
230 
231 	ASSERT(rx->local != NULL);
232 	ASSERT(rx->sk.sk_state > RXRPC_UNCONNECTED);
233 
234 	if (rx->srx.transport_type != srx->transport_type)
235 		return ERR_PTR(-ESOCKTNOSUPPORT);
236 	if (rx->srx.transport.family != srx->transport.family)
237 		return ERR_PTR(-EAFNOSUPPORT);
238 
239 	/* find a remote transport endpoint from the local one */
240 	peer = rxrpc_get_peer(srx, gfp);
241 	if (IS_ERR(peer))
242 		return ERR_CAST(peer);
243 
244 	/* find a transport */
245 	trans = rxrpc_get_transport(rx->local, peer, gfp);
246 	rxrpc_put_peer(peer);
247 	_leave(" = %p", trans);
248 	return trans;
249 }
250 
251 /**
252  * rxrpc_kernel_begin_call - Allow a kernel service to begin a call
253  * @sock: The socket on which to make the call
254  * @srx: The address of the peer to contact (defaults to socket setting)
255  * @key: The security context to use (defaults to socket setting)
256  * @user_call_ID: The ID to use
257  *
258  * Allow a kernel service to begin a call on the nominated socket.  This just
259  * sets up all the internal tracking structures and allocates connection and
260  * call IDs as appropriate.  The call to be used is returned.
261  *
262  * The default socket destination address and security may be overridden by
263  * supplying @srx and @key.
264  */
265 struct rxrpc_call *rxrpc_kernel_begin_call(struct socket *sock,
266 					   struct sockaddr_rxrpc *srx,
267 					   struct key *key,
268 					   unsigned long user_call_ID,
269 					   gfp_t gfp)
270 {
271 	struct rxrpc_conn_bundle *bundle;
272 	struct rxrpc_transport *trans;
273 	struct rxrpc_call *call;
274 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
275 	__be16 service_id;
276 
277 	_enter(",,%x,%lx", key_serial(key), user_call_ID);
278 
279 	lock_sock(&rx->sk);
280 
281 	if (srx) {
282 		trans = rxrpc_name_to_transport(sock, (struct sockaddr *) srx,
283 						sizeof(*srx), 0, gfp);
284 		if (IS_ERR(trans)) {
285 			call = ERR_CAST(trans);
286 			trans = NULL;
287 			goto out;
288 		}
289 	} else {
290 		trans = rx->trans;
291 		if (!trans) {
292 			call = ERR_PTR(-ENOTCONN);
293 			goto out;
294 		}
295 		atomic_inc(&trans->usage);
296 	}
297 
298 	service_id = rx->service_id;
299 	if (srx)
300 		service_id = htons(srx->srx_service);
301 
302 	if (!key)
303 		key = rx->key;
304 	if (key && !key->payload.data)
305 		key = NULL; /* a no-security key */
306 
307 	bundle = rxrpc_get_bundle(rx, trans, key, service_id, gfp);
308 	if (IS_ERR(bundle)) {
309 		call = ERR_CAST(bundle);
310 		goto out;
311 	}
312 
313 	call = rxrpc_get_client_call(rx, trans, bundle, user_call_ID, true,
314 				     gfp);
315 	rxrpc_put_bundle(trans, bundle);
316 out:
317 	rxrpc_put_transport(trans);
318 	release_sock(&rx->sk);
319 	_leave(" = %p", call);
320 	return call;
321 }
322 
323 EXPORT_SYMBOL(rxrpc_kernel_begin_call);
324 
325 /**
326  * rxrpc_kernel_end_call - Allow a kernel service to end a call it was using
327  * @call: The call to end
328  *
329  * Allow a kernel service to end a call it was using.  The call must be
330  * complete before this is called (the call should be aborted if necessary).
331  */
332 void rxrpc_kernel_end_call(struct rxrpc_call *call)
333 {
334 	_enter("%d{%d}", call->debug_id, atomic_read(&call->usage));
335 	rxrpc_remove_user_ID(call->socket, call);
336 	rxrpc_put_call(call);
337 }
338 
339 EXPORT_SYMBOL(rxrpc_kernel_end_call);
340 
341 /**
342  * rxrpc_kernel_intercept_rx_messages - Intercept received RxRPC messages
343  * @sock: The socket to intercept received messages on
344  * @interceptor: The function to pass the messages to
345  *
346  * Allow a kernel service to intercept messages heading for the Rx queue on an
347  * RxRPC socket.  They get passed to the specified function instead.
348  * @interceptor should free the socket buffers it is given.  @interceptor is
349  * called with the socket receive queue spinlock held and softirqs disabled -
350  * this ensures that the messages will be delivered in the right order.
351  */
352 void rxrpc_kernel_intercept_rx_messages(struct socket *sock,
353 					rxrpc_interceptor_t interceptor)
354 {
355 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
356 
357 	_enter("");
358 	rx->interceptor = interceptor;
359 }
360 
361 EXPORT_SYMBOL(rxrpc_kernel_intercept_rx_messages);
362 
363 /*
364  * connect an RxRPC socket
365  * - this just targets it at a specific destination; no actual connection
366  *   negotiation takes place
367  */
368 static int rxrpc_connect(struct socket *sock, struct sockaddr *addr,
369 			 int addr_len, int flags)
370 {
371 	struct sockaddr_rxrpc *srx = (struct sockaddr_rxrpc *) addr;
372 	struct sock *sk = sock->sk;
373 	struct rxrpc_transport *trans;
374 	struct rxrpc_local *local;
375 	struct rxrpc_sock *rx = rxrpc_sk(sk);
376 	int ret;
377 
378 	_enter("%p,%p,%d,%d", rx, addr, addr_len, flags);
379 
380 	ret = rxrpc_validate_address(rx, srx, addr_len);
381 	if (ret < 0) {
382 		_leave(" = %d [bad addr]", ret);
383 		return ret;
384 	}
385 
386 	lock_sock(&rx->sk);
387 
388 	switch (rx->sk.sk_state) {
389 	case RXRPC_UNCONNECTED:
390 		/* find a local transport endpoint if we don't have one already */
391 		ASSERTCMP(rx->local, ==, NULL);
392 		rx->srx.srx_family = AF_RXRPC;
393 		rx->srx.srx_service = 0;
394 		rx->srx.transport_type = srx->transport_type;
395 		rx->srx.transport_len = sizeof(sa_family_t);
396 		rx->srx.transport.family = srx->transport.family;
397 		local = rxrpc_lookup_local(&rx->srx);
398 		if (IS_ERR(local)) {
399 			release_sock(&rx->sk);
400 			return PTR_ERR(local);
401 		}
402 		rx->local = local;
403 		rx->sk.sk_state = RXRPC_CLIENT_BOUND;
404 	case RXRPC_CLIENT_BOUND:
405 		break;
406 	case RXRPC_CLIENT_CONNECTED:
407 		release_sock(&rx->sk);
408 		return -EISCONN;
409 	default:
410 		release_sock(&rx->sk);
411 		return -EBUSY; /* server sockets can't connect as well */
412 	}
413 
414 	trans = rxrpc_name_to_transport(sock, addr, addr_len, flags,
415 					GFP_KERNEL);
416 	if (IS_ERR(trans)) {
417 		release_sock(&rx->sk);
418 		_leave(" = %ld", PTR_ERR(trans));
419 		return PTR_ERR(trans);
420 	}
421 
422 	rx->trans = trans;
423 	rx->service_id = htons(srx->srx_service);
424 	rx->sk.sk_state = RXRPC_CLIENT_CONNECTED;
425 
426 	release_sock(&rx->sk);
427 	return 0;
428 }
429 
430 /*
431  * send a message through an RxRPC socket
432  * - in a client this does a number of things:
433  *   - finds/sets up a connection for the security specified (if any)
434  *   - initiates a call (ID in control data)
435  *   - ends the request phase of a call (if MSG_MORE is not set)
436  *   - sends a call data packet
437  *   - may send an abort (abort code in control data)
438  */
439 static int rxrpc_sendmsg(struct kiocb *iocb, struct socket *sock,
440 			 struct msghdr *m, size_t len)
441 {
442 	struct rxrpc_transport *trans;
443 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
444 	int ret;
445 
446 	_enter(",{%d},,%zu", rx->sk.sk_state, len);
447 
448 	if (m->msg_flags & MSG_OOB)
449 		return -EOPNOTSUPP;
450 
451 	if (m->msg_name) {
452 		ret = rxrpc_validate_address(rx, m->msg_name, m->msg_namelen);
453 		if (ret < 0) {
454 			_leave(" = %d [bad addr]", ret);
455 			return ret;
456 		}
457 	}
458 
459 	trans = NULL;
460 	lock_sock(&rx->sk);
461 
462 	if (m->msg_name) {
463 		ret = -EISCONN;
464 		trans = rxrpc_name_to_transport(sock, m->msg_name,
465 						m->msg_namelen, 0, GFP_KERNEL);
466 		if (IS_ERR(trans)) {
467 			ret = PTR_ERR(trans);
468 			trans = NULL;
469 			goto out;
470 		}
471 	} else {
472 		trans = rx->trans;
473 		if (trans)
474 			atomic_inc(&trans->usage);
475 	}
476 
477 	switch (rx->sk.sk_state) {
478 	case RXRPC_SERVER_LISTENING:
479 		if (!m->msg_name) {
480 			ret = rxrpc_server_sendmsg(iocb, rx, m, len);
481 			break;
482 		}
483 	case RXRPC_SERVER_BOUND:
484 	case RXRPC_CLIENT_BOUND:
485 		if (!m->msg_name) {
486 			ret = -ENOTCONN;
487 			break;
488 		}
489 	case RXRPC_CLIENT_CONNECTED:
490 		ret = rxrpc_client_sendmsg(iocb, rx, trans, m, len);
491 		break;
492 	default:
493 		ret = -ENOTCONN;
494 		break;
495 	}
496 
497 out:
498 	release_sock(&rx->sk);
499 	if (trans)
500 		rxrpc_put_transport(trans);
501 	_leave(" = %d", ret);
502 	return ret;
503 }
504 
505 /*
506  * set RxRPC socket options
507  */
508 static int rxrpc_setsockopt(struct socket *sock, int level, int optname,
509 			    char __user *optval, int optlen)
510 {
511 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
512 	unsigned min_sec_level;
513 	int ret;
514 
515 	_enter(",%d,%d,,%d", level, optname, optlen);
516 
517 	lock_sock(&rx->sk);
518 	ret = -EOPNOTSUPP;
519 
520 	if (level == SOL_RXRPC) {
521 		switch (optname) {
522 		case RXRPC_EXCLUSIVE_CONNECTION:
523 			ret = -EINVAL;
524 			if (optlen != 0)
525 				goto error;
526 			ret = -EISCONN;
527 			if (rx->sk.sk_state != RXRPC_UNCONNECTED)
528 				goto error;
529 			set_bit(RXRPC_SOCK_EXCLUSIVE_CONN, &rx->flags);
530 			goto success;
531 
532 		case RXRPC_SECURITY_KEY:
533 			ret = -EINVAL;
534 			if (rx->key)
535 				goto error;
536 			ret = -EISCONN;
537 			if (rx->sk.sk_state != RXRPC_UNCONNECTED)
538 				goto error;
539 			ret = rxrpc_request_key(rx, optval, optlen);
540 			goto error;
541 
542 		case RXRPC_SECURITY_KEYRING:
543 			ret = -EINVAL;
544 			if (rx->key)
545 				goto error;
546 			ret = -EISCONN;
547 			if (rx->sk.sk_state != RXRPC_UNCONNECTED)
548 				goto error;
549 			ret = rxrpc_server_keyring(rx, optval, optlen);
550 			goto error;
551 
552 		case RXRPC_MIN_SECURITY_LEVEL:
553 			ret = -EINVAL;
554 			if (optlen != sizeof(unsigned))
555 				goto error;
556 			ret = -EISCONN;
557 			if (rx->sk.sk_state != RXRPC_UNCONNECTED)
558 				goto error;
559 			ret = get_user(min_sec_level,
560 				       (unsigned __user *) optval);
561 			if (ret < 0)
562 				goto error;
563 			ret = -EINVAL;
564 			if (min_sec_level > RXRPC_SECURITY_MAX)
565 				goto error;
566 			rx->min_sec_level = min_sec_level;
567 			goto success;
568 
569 		default:
570 			break;
571 		}
572 	}
573 
574 success:
575 	ret = 0;
576 error:
577 	release_sock(&rx->sk);
578 	return ret;
579 }
580 
581 /*
582  * permit an RxRPC socket to be polled
583  */
584 static unsigned int rxrpc_poll(struct file *file, struct socket *sock,
585 			       poll_table *wait)
586 {
587 	unsigned int mask;
588 	struct sock *sk = sock->sk;
589 
590 	poll_wait(file, sk->sk_sleep, wait);
591 	mask = 0;
592 
593 	/* the socket is readable if there are any messages waiting on the Rx
594 	 * queue */
595 	if (!skb_queue_empty(&sk->sk_receive_queue))
596 		mask |= POLLIN | POLLRDNORM;
597 
598 	/* the socket is writable if there is space to add new data to the
599 	 * socket; there is no guarantee that any particular call in progress
600 	 * on the socket may have space in the Tx ACK window */
601 	if (rxrpc_writable(sk))
602 		mask |= POLLOUT | POLLWRNORM;
603 
604 	return mask;
605 }
606 
607 /*
608  * create an RxRPC socket
609  */
610 static int rxrpc_create(struct net *net, struct socket *sock, int protocol)
611 {
612 	struct rxrpc_sock *rx;
613 	struct sock *sk;
614 
615 	_enter("%p,%d", sock, protocol);
616 
617 	if (net != &init_net)
618 		return -EAFNOSUPPORT;
619 
620 	/* we support transport protocol UDP only */
621 	if (protocol != PF_INET)
622 		return -EPROTONOSUPPORT;
623 
624 	if (sock->type != SOCK_DGRAM)
625 		return -ESOCKTNOSUPPORT;
626 
627 	sock->ops = &rxrpc_rpc_ops;
628 	sock->state = SS_UNCONNECTED;
629 
630 	sk = sk_alloc(net, PF_RXRPC, GFP_KERNEL, &rxrpc_proto);
631 	if (!sk)
632 		return -ENOMEM;
633 
634 	sock_init_data(sock, sk);
635 	sk->sk_state		= RXRPC_UNCONNECTED;
636 	sk->sk_write_space	= rxrpc_write_space;
637 	sk->sk_max_ack_backlog	= sysctl_rxrpc_max_qlen;
638 	sk->sk_destruct		= rxrpc_sock_destructor;
639 
640 	rx = rxrpc_sk(sk);
641 	rx->proto = protocol;
642 	rx->calls = RB_ROOT;
643 
644 	INIT_LIST_HEAD(&rx->listen_link);
645 	INIT_LIST_HEAD(&rx->secureq);
646 	INIT_LIST_HEAD(&rx->acceptq);
647 	rwlock_init(&rx->call_lock);
648 	memset(&rx->srx, 0, sizeof(rx->srx));
649 
650 	_leave(" = 0 [%p]", rx);
651 	return 0;
652 }
653 
654 /*
655  * RxRPC socket destructor
656  */
657 static void rxrpc_sock_destructor(struct sock *sk)
658 {
659 	_enter("%p", sk);
660 
661 	rxrpc_purge_queue(&sk->sk_receive_queue);
662 
663 	BUG_TRAP(!atomic_read(&sk->sk_wmem_alloc));
664 	BUG_TRAP(sk_unhashed(sk));
665 	BUG_TRAP(!sk->sk_socket);
666 
667 	if (!sock_flag(sk, SOCK_DEAD)) {
668 		printk("Attempt to release alive rxrpc socket: %p\n", sk);
669 		return;
670 	}
671 }
672 
673 /*
674  * release an RxRPC socket
675  */
676 static int rxrpc_release_sock(struct sock *sk)
677 {
678 	struct rxrpc_sock *rx = rxrpc_sk(sk);
679 
680 	_enter("%p{%d,%d}", sk, sk->sk_state, atomic_read(&sk->sk_refcnt));
681 
682 	/* declare the socket closed for business */
683 	sock_orphan(sk);
684 	sk->sk_shutdown = SHUTDOWN_MASK;
685 
686 	spin_lock_bh(&sk->sk_receive_queue.lock);
687 	sk->sk_state = RXRPC_CLOSE;
688 	spin_unlock_bh(&sk->sk_receive_queue.lock);
689 
690 	ASSERTCMP(rx->listen_link.next, !=, LIST_POISON1);
691 
692 	if (!list_empty(&rx->listen_link)) {
693 		write_lock_bh(&rx->local->services_lock);
694 		list_del(&rx->listen_link);
695 		write_unlock_bh(&rx->local->services_lock);
696 	}
697 
698 	/* try to flush out this socket */
699 	rxrpc_release_calls_on_socket(rx);
700 	flush_workqueue(rxrpc_workqueue);
701 	rxrpc_purge_queue(&sk->sk_receive_queue);
702 
703 	if (rx->conn) {
704 		rxrpc_put_connection(rx->conn);
705 		rx->conn = NULL;
706 	}
707 
708 	if (rx->bundle) {
709 		rxrpc_put_bundle(rx->trans, rx->bundle);
710 		rx->bundle = NULL;
711 	}
712 	if (rx->trans) {
713 		rxrpc_put_transport(rx->trans);
714 		rx->trans = NULL;
715 	}
716 	if (rx->local) {
717 		rxrpc_put_local(rx->local);
718 		rx->local = NULL;
719 	}
720 
721 	key_put(rx->key);
722 	rx->key = NULL;
723 	key_put(rx->securities);
724 	rx->securities = NULL;
725 	sock_put(sk);
726 
727 	_leave(" = 0");
728 	return 0;
729 }
730 
731 /*
732  * release an RxRPC BSD socket on close() or equivalent
733  */
734 static int rxrpc_release(struct socket *sock)
735 {
736 	struct sock *sk = sock->sk;
737 
738 	_enter("%p{%p}", sock, sk);
739 
740 	if (!sk)
741 		return 0;
742 
743 	sock->sk = NULL;
744 
745 	return rxrpc_release_sock(sk);
746 }
747 
748 /*
749  * RxRPC network protocol
750  */
751 static const struct proto_ops rxrpc_rpc_ops = {
752 	.family		= PF_UNIX,
753 	.owner		= THIS_MODULE,
754 	.release	= rxrpc_release,
755 	.bind		= rxrpc_bind,
756 	.connect	= rxrpc_connect,
757 	.socketpair	= sock_no_socketpair,
758 	.accept		= sock_no_accept,
759 	.getname	= sock_no_getname,
760 	.poll		= rxrpc_poll,
761 	.ioctl		= sock_no_ioctl,
762 	.listen		= rxrpc_listen,
763 	.shutdown	= sock_no_shutdown,
764 	.setsockopt	= rxrpc_setsockopt,
765 	.getsockopt	= sock_no_getsockopt,
766 	.sendmsg	= rxrpc_sendmsg,
767 	.recvmsg	= rxrpc_recvmsg,
768 	.mmap		= sock_no_mmap,
769 	.sendpage	= sock_no_sendpage,
770 };
771 
772 static struct proto rxrpc_proto = {
773 	.name		= "RXRPC",
774 	.owner		= THIS_MODULE,
775 	.obj_size	= sizeof(struct rxrpc_sock),
776 	.max_header	= sizeof(struct rxrpc_header),
777 };
778 
779 static struct net_proto_family rxrpc_family_ops = {
780 	.family	= PF_RXRPC,
781 	.create = rxrpc_create,
782 	.owner	= THIS_MODULE,
783 };
784 
785 /*
786  * initialise and register the RxRPC protocol
787  */
788 static int __init af_rxrpc_init(void)
789 {
790 	struct sk_buff *dummy_skb;
791 	int ret = -1;
792 
793 	BUILD_BUG_ON(sizeof(struct rxrpc_skb_priv) > sizeof(dummy_skb->cb));
794 
795 	rxrpc_epoch = htonl(get_seconds());
796 
797 	ret = -ENOMEM;
798 	rxrpc_call_jar = kmem_cache_create(
799 		"rxrpc_call_jar", sizeof(struct rxrpc_call), 0,
800 		SLAB_HWCACHE_ALIGN, NULL);
801 	if (!rxrpc_call_jar) {
802 		printk(KERN_NOTICE "RxRPC: Failed to allocate call jar\n");
803 		goto error_call_jar;
804 	}
805 
806 	rxrpc_workqueue = create_workqueue("krxrpcd");
807 	if (!rxrpc_workqueue) {
808 		printk(KERN_NOTICE "RxRPC: Failed to allocate work queue\n");
809 		goto error_work_queue;
810 	}
811 
812 	ret = proto_register(&rxrpc_proto, 1);
813 	if (ret < 0) {
814 		printk(KERN_CRIT "RxRPC: Cannot register protocol\n");
815 		goto error_proto;
816 	}
817 
818 	ret = sock_register(&rxrpc_family_ops);
819 	if (ret < 0) {
820 		printk(KERN_CRIT "RxRPC: Cannot register socket family\n");
821 		goto error_sock;
822 	}
823 
824 	ret = register_key_type(&key_type_rxrpc);
825 	if (ret < 0) {
826 		printk(KERN_CRIT "RxRPC: Cannot register client key type\n");
827 		goto error_key_type;
828 	}
829 
830 	ret = register_key_type(&key_type_rxrpc_s);
831 	if (ret < 0) {
832 		printk(KERN_CRIT "RxRPC: Cannot register server key type\n");
833 		goto error_key_type_s;
834 	}
835 
836 #ifdef CONFIG_PROC_FS
837 	proc_net_fops_create(&init_net, "rxrpc_calls", 0, &rxrpc_call_seq_fops);
838 	proc_net_fops_create(&init_net, "rxrpc_conns", 0, &rxrpc_connection_seq_fops);
839 #endif
840 	return 0;
841 
842 error_key_type_s:
843 	unregister_key_type(&key_type_rxrpc);
844 error_key_type:
845 	sock_unregister(PF_RXRPC);
846 error_sock:
847 	proto_unregister(&rxrpc_proto);
848 error_proto:
849 	destroy_workqueue(rxrpc_workqueue);
850 error_work_queue:
851 	kmem_cache_destroy(rxrpc_call_jar);
852 error_call_jar:
853 	return ret;
854 }
855 
856 /*
857  * unregister the RxRPC protocol
858  */
859 static void __exit af_rxrpc_exit(void)
860 {
861 	_enter("");
862 	unregister_key_type(&key_type_rxrpc_s);
863 	unregister_key_type(&key_type_rxrpc);
864 	sock_unregister(PF_RXRPC);
865 	proto_unregister(&rxrpc_proto);
866 	rxrpc_destroy_all_calls();
867 	rxrpc_destroy_all_connections();
868 	rxrpc_destroy_all_transports();
869 	rxrpc_destroy_all_peers();
870 	rxrpc_destroy_all_locals();
871 
872 	ASSERTCMP(atomic_read(&rxrpc_n_skbs), ==, 0);
873 
874 	_debug("flush scheduled work");
875 	flush_workqueue(rxrpc_workqueue);
876 	proc_net_remove(&init_net, "rxrpc_conns");
877 	proc_net_remove(&init_net, "rxrpc_calls");
878 	destroy_workqueue(rxrpc_workqueue);
879 	kmem_cache_destroy(rxrpc_call_jar);
880 	_leave("");
881 }
882 
883 module_init(af_rxrpc_init);
884 module_exit(af_rxrpc_exit);
885