xref: /linux/net/rxrpc/af_rxrpc.c (revision 7181e5590e5ba898804aef3ee6be7f27606e6f8b)
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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
13 
14 #include <linux/module.h>
15 #include <linux/kernel.h>
16 #include <linux/net.h>
17 #include <linux/slab.h>
18 #include <linux/skbuff.h>
19 #include <linux/random.h>
20 #include <linux/poll.h>
21 #include <linux/proc_fs.h>
22 #include <linux/key-type.h>
23 #include <net/net_namespace.h>
24 #include <net/sock.h>
25 #include <net/af_rxrpc.h>
26 #define CREATE_TRACE_POINTS
27 #include "ar-internal.h"
28 
29 MODULE_DESCRIPTION("RxRPC network protocol");
30 MODULE_AUTHOR("Red Hat, Inc.");
31 MODULE_LICENSE("GPL");
32 MODULE_ALIAS_NETPROTO(PF_RXRPC);
33 
34 unsigned int rxrpc_debug; // = RXRPC_DEBUG_KPROTO;
35 module_param_named(debug, rxrpc_debug, uint, S_IWUSR | S_IRUGO);
36 MODULE_PARM_DESC(debug, "RxRPC debugging mask");
37 
38 static struct proto rxrpc_proto;
39 static const struct proto_ops rxrpc_rpc_ops;
40 
41 /* local epoch for detecting local-end reset */
42 u32 rxrpc_epoch;
43 
44 /* current debugging ID */
45 atomic_t rxrpc_debug_id;
46 
47 /* count of skbs currently in use */
48 atomic_t rxrpc_n_tx_skbs, rxrpc_n_rx_skbs;
49 
50 struct workqueue_struct *rxrpc_workqueue;
51 
52 static void rxrpc_sock_destructor(struct sock *);
53 
54 /*
55  * see if an RxRPC socket is currently writable
56  */
57 static inline int rxrpc_writable(struct sock *sk)
58 {
59 	return atomic_read(&sk->sk_wmem_alloc) < (size_t) sk->sk_sndbuf;
60 }
61 
62 /*
63  * wait for write bufferage to become available
64  */
65 static void rxrpc_write_space(struct sock *sk)
66 {
67 	_enter("%p", sk);
68 	rcu_read_lock();
69 	if (rxrpc_writable(sk)) {
70 		struct socket_wq *wq = rcu_dereference(sk->sk_wq);
71 
72 		if (skwq_has_sleeper(wq))
73 			wake_up_interruptible(&wq->wait);
74 		sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
75 	}
76 	rcu_read_unlock();
77 }
78 
79 /*
80  * validate an RxRPC address
81  */
82 static int rxrpc_validate_address(struct rxrpc_sock *rx,
83 				  struct sockaddr_rxrpc *srx,
84 				  int len)
85 {
86 	unsigned int tail;
87 
88 	if (len < sizeof(struct sockaddr_rxrpc))
89 		return -EINVAL;
90 
91 	if (srx->srx_family != AF_RXRPC)
92 		return -EAFNOSUPPORT;
93 
94 	if (srx->transport_type != SOCK_DGRAM)
95 		return -ESOCKTNOSUPPORT;
96 
97 	len -= offsetof(struct sockaddr_rxrpc, transport);
98 	if (srx->transport_len < sizeof(sa_family_t) ||
99 	    srx->transport_len > len)
100 		return -EINVAL;
101 
102 	if (srx->transport.family != rx->family)
103 		return -EAFNOSUPPORT;
104 
105 	switch (srx->transport.family) {
106 	case AF_INET:
107 		if (srx->transport_len < sizeof(struct sockaddr_in))
108 			return -EINVAL;
109 		tail = offsetof(struct sockaddr_rxrpc, transport.sin.__pad);
110 		break;
111 
112 #ifdef CONFIG_AF_RXRPC_IPV6
113 	case AF_INET6:
114 		if (srx->transport_len < sizeof(struct sockaddr_in6))
115 			return -EINVAL;
116 		tail = offsetof(struct sockaddr_rxrpc, transport) +
117 			sizeof(struct sockaddr_in6);
118 		break;
119 #endif
120 
121 	default:
122 		return -EAFNOSUPPORT;
123 	}
124 
125 	if (tail < len)
126 		memset((void *)srx + tail, 0, len - tail);
127 	_debug("INET: %pISp", &srx->transport);
128 	return 0;
129 }
130 
131 /*
132  * bind a local address to an RxRPC socket
133  */
134 static int rxrpc_bind(struct socket *sock, struct sockaddr *saddr, int len)
135 {
136 	struct sockaddr_rxrpc *srx = (struct sockaddr_rxrpc *)saddr;
137 	struct sock *sk = sock->sk;
138 	struct rxrpc_local *local;
139 	struct rxrpc_sock *rx = rxrpc_sk(sk);
140 	u16 service_id = srx->srx_service;
141 	int ret;
142 
143 	_enter("%p,%p,%d", rx, saddr, len);
144 
145 	ret = rxrpc_validate_address(rx, srx, len);
146 	if (ret < 0)
147 		goto error;
148 
149 	lock_sock(&rx->sk);
150 
151 	if (rx->sk.sk_state != RXRPC_UNBOUND) {
152 		ret = -EINVAL;
153 		goto error_unlock;
154 	}
155 
156 	memcpy(&rx->srx, srx, sizeof(rx->srx));
157 
158 	local = rxrpc_lookup_local(&rx->srx);
159 	if (IS_ERR(local)) {
160 		ret = PTR_ERR(local);
161 		goto error_unlock;
162 	}
163 
164 	if (service_id) {
165 		write_lock(&local->services_lock);
166 		if (rcu_access_pointer(local->service))
167 			goto service_in_use;
168 		rx->local = local;
169 		rcu_assign_pointer(local->service, rx);
170 		write_unlock(&local->services_lock);
171 
172 		rx->sk.sk_state = RXRPC_SERVER_BOUND;
173 	} else {
174 		rx->local = local;
175 		rx->sk.sk_state = RXRPC_CLIENT_BOUND;
176 	}
177 
178 	release_sock(&rx->sk);
179 	_leave(" = 0");
180 	return 0;
181 
182 service_in_use:
183 	write_unlock(&local->services_lock);
184 	rxrpc_put_local(local);
185 	ret = -EADDRINUSE;
186 error_unlock:
187 	release_sock(&rx->sk);
188 error:
189 	_leave(" = %d", ret);
190 	return ret;
191 }
192 
193 /*
194  * set the number of pending calls permitted on a listening socket
195  */
196 static int rxrpc_listen(struct socket *sock, int backlog)
197 {
198 	struct sock *sk = sock->sk;
199 	struct rxrpc_sock *rx = rxrpc_sk(sk);
200 	unsigned int max, old;
201 	int ret;
202 
203 	_enter("%p,%d", rx, backlog);
204 
205 	lock_sock(&rx->sk);
206 
207 	switch (rx->sk.sk_state) {
208 	case RXRPC_UNBOUND:
209 		ret = -EADDRNOTAVAIL;
210 		break;
211 	case RXRPC_SERVER_BOUND:
212 		ASSERT(rx->local != NULL);
213 		max = READ_ONCE(rxrpc_max_backlog);
214 		ret = -EINVAL;
215 		if (backlog == INT_MAX)
216 			backlog = max;
217 		else if (backlog < 0 || backlog > max)
218 			break;
219 		old = sk->sk_max_ack_backlog;
220 		sk->sk_max_ack_backlog = backlog;
221 		ret = rxrpc_service_prealloc(rx, GFP_KERNEL);
222 		if (ret == 0)
223 			rx->sk.sk_state = RXRPC_SERVER_LISTENING;
224 		else
225 			sk->sk_max_ack_backlog = old;
226 		break;
227 	default:
228 		ret = -EBUSY;
229 		break;
230 	}
231 
232 	release_sock(&rx->sk);
233 	_leave(" = %d", ret);
234 	return ret;
235 }
236 
237 /**
238  * rxrpc_kernel_begin_call - Allow a kernel service to begin a call
239  * @sock: The socket on which to make the call
240  * @srx: The address of the peer to contact
241  * @key: The security context to use (defaults to socket setting)
242  * @user_call_ID: The ID to use
243  * @gfp: The allocation constraints
244  * @notify_rx: Where to send notifications instead of socket queue
245  *
246  * Allow a kernel service to begin a call on the nominated socket.  This just
247  * sets up all the internal tracking structures and allocates connection and
248  * call IDs as appropriate.  The call to be used is returned.
249  *
250  * The default socket destination address and security may be overridden by
251  * supplying @srx and @key.
252  */
253 struct rxrpc_call *rxrpc_kernel_begin_call(struct socket *sock,
254 					   struct sockaddr_rxrpc *srx,
255 					   struct key *key,
256 					   unsigned long user_call_ID,
257 					   gfp_t gfp,
258 					   rxrpc_notify_rx_t notify_rx)
259 {
260 	struct rxrpc_conn_parameters cp;
261 	struct rxrpc_call *call;
262 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
263 	int ret;
264 
265 	_enter(",,%x,%lx", key_serial(key), user_call_ID);
266 
267 	ret = rxrpc_validate_address(rx, srx, sizeof(*srx));
268 	if (ret < 0)
269 		return ERR_PTR(ret);
270 
271 	lock_sock(&rx->sk);
272 
273 	if (!key)
274 		key = rx->key;
275 	if (key && !key->payload.data[0])
276 		key = NULL; /* a no-security key */
277 
278 	memset(&cp, 0, sizeof(cp));
279 	cp.local		= rx->local;
280 	cp.key			= key;
281 	cp.security_level	= 0;
282 	cp.exclusive		= false;
283 	cp.service_id		= srx->srx_service;
284 	call = rxrpc_new_client_call(rx, &cp, srx, user_call_ID, gfp);
285 	if (!IS_ERR(call))
286 		call->notify_rx = notify_rx;
287 
288 	release_sock(&rx->sk);
289 	_leave(" = %p", call);
290 	return call;
291 }
292 EXPORT_SYMBOL(rxrpc_kernel_begin_call);
293 
294 /**
295  * rxrpc_kernel_end_call - Allow a kernel service to end a call it was using
296  * @sock: The socket the call is on
297  * @call: The call to end
298  *
299  * Allow a kernel service to end a call it was using.  The call must be
300  * complete before this is called (the call should be aborted if necessary).
301  */
302 void rxrpc_kernel_end_call(struct socket *sock, struct rxrpc_call *call)
303 {
304 	_enter("%d{%d}", call->debug_id, atomic_read(&call->usage));
305 	rxrpc_release_call(rxrpc_sk(sock->sk), call);
306 	rxrpc_put_call(call, rxrpc_call_put_kernel);
307 }
308 EXPORT_SYMBOL(rxrpc_kernel_end_call);
309 
310 /**
311  * rxrpc_kernel_new_call_notification - Get notifications of new calls
312  * @sock: The socket to intercept received messages on
313  * @notify_new_call: Function to be called when new calls appear
314  * @discard_new_call: Function to discard preallocated calls
315  *
316  * Allow a kernel service to be given notifications about new calls.
317  */
318 void rxrpc_kernel_new_call_notification(
319 	struct socket *sock,
320 	rxrpc_notify_new_call_t notify_new_call,
321 	rxrpc_discard_new_call_t discard_new_call)
322 {
323 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
324 
325 	rx->notify_new_call = notify_new_call;
326 	rx->discard_new_call = discard_new_call;
327 }
328 EXPORT_SYMBOL(rxrpc_kernel_new_call_notification);
329 
330 /*
331  * connect an RxRPC socket
332  * - this just targets it at a specific destination; no actual connection
333  *   negotiation takes place
334  */
335 static int rxrpc_connect(struct socket *sock, struct sockaddr *addr,
336 			 int addr_len, int flags)
337 {
338 	struct sockaddr_rxrpc *srx = (struct sockaddr_rxrpc *)addr;
339 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
340 	int ret;
341 
342 	_enter("%p,%p,%d,%d", rx, addr, addr_len, flags);
343 
344 	ret = rxrpc_validate_address(rx, srx, addr_len);
345 	if (ret < 0) {
346 		_leave(" = %d [bad addr]", ret);
347 		return ret;
348 	}
349 
350 	lock_sock(&rx->sk);
351 
352 	ret = -EISCONN;
353 	if (test_bit(RXRPC_SOCK_CONNECTED, &rx->flags))
354 		goto error;
355 
356 	switch (rx->sk.sk_state) {
357 	case RXRPC_UNBOUND:
358 		rx->sk.sk_state = RXRPC_CLIENT_UNBOUND;
359 	case RXRPC_CLIENT_UNBOUND:
360 	case RXRPC_CLIENT_BOUND:
361 		break;
362 	default:
363 		ret = -EBUSY;
364 		goto error;
365 	}
366 
367 	rx->connect_srx = *srx;
368 	set_bit(RXRPC_SOCK_CONNECTED, &rx->flags);
369 	ret = 0;
370 
371 error:
372 	release_sock(&rx->sk);
373 	return ret;
374 }
375 
376 /*
377  * send a message through an RxRPC socket
378  * - in a client this does a number of things:
379  *   - finds/sets up a connection for the security specified (if any)
380  *   - initiates a call (ID in control data)
381  *   - ends the request phase of a call (if MSG_MORE is not set)
382  *   - sends a call data packet
383  *   - may send an abort (abort code in control data)
384  */
385 static int rxrpc_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
386 {
387 	struct rxrpc_local *local;
388 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
389 	int ret;
390 
391 	_enter(",{%d},,%zu", rx->sk.sk_state, len);
392 
393 	if (m->msg_flags & MSG_OOB)
394 		return -EOPNOTSUPP;
395 
396 	if (m->msg_name) {
397 		ret = rxrpc_validate_address(rx, m->msg_name, m->msg_namelen);
398 		if (ret < 0) {
399 			_leave(" = %d [bad addr]", ret);
400 			return ret;
401 		}
402 	}
403 
404 	lock_sock(&rx->sk);
405 
406 	switch (rx->sk.sk_state) {
407 	case RXRPC_UNBOUND:
408 		rx->srx.srx_family = AF_RXRPC;
409 		rx->srx.srx_service = 0;
410 		rx->srx.transport_type = SOCK_DGRAM;
411 		rx->srx.transport.family = rx->family;
412 		switch (rx->family) {
413 		case AF_INET:
414 			rx->srx.transport_len = sizeof(struct sockaddr_in);
415 			break;
416 #ifdef CONFIG_AF_RXRPC_IPV6
417 		case AF_INET6:
418 			rx->srx.transport_len = sizeof(struct sockaddr_in6);
419 			break;
420 #endif
421 		default:
422 			ret = -EAFNOSUPPORT;
423 			goto error_unlock;
424 		}
425 		local = rxrpc_lookup_local(&rx->srx);
426 		if (IS_ERR(local)) {
427 			ret = PTR_ERR(local);
428 			goto error_unlock;
429 		}
430 
431 		rx->local = local;
432 		rx->sk.sk_state = RXRPC_CLIENT_UNBOUND;
433 		/* Fall through */
434 
435 	case RXRPC_CLIENT_UNBOUND:
436 	case RXRPC_CLIENT_BOUND:
437 		if (!m->msg_name &&
438 		    test_bit(RXRPC_SOCK_CONNECTED, &rx->flags)) {
439 			m->msg_name = &rx->connect_srx;
440 			m->msg_namelen = sizeof(rx->connect_srx);
441 		}
442 	case RXRPC_SERVER_BOUND:
443 	case RXRPC_SERVER_LISTENING:
444 		ret = rxrpc_do_sendmsg(rx, m, len);
445 		break;
446 	default:
447 		ret = -EINVAL;
448 		break;
449 	}
450 
451 error_unlock:
452 	release_sock(&rx->sk);
453 	_leave(" = %d", ret);
454 	return ret;
455 }
456 
457 /*
458  * set RxRPC socket options
459  */
460 static int rxrpc_setsockopt(struct socket *sock, int level, int optname,
461 			    char __user *optval, unsigned int optlen)
462 {
463 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
464 	unsigned int min_sec_level;
465 	int ret;
466 
467 	_enter(",%d,%d,,%d", level, optname, optlen);
468 
469 	lock_sock(&rx->sk);
470 	ret = -EOPNOTSUPP;
471 
472 	if (level == SOL_RXRPC) {
473 		switch (optname) {
474 		case RXRPC_EXCLUSIVE_CONNECTION:
475 			ret = -EINVAL;
476 			if (optlen != 0)
477 				goto error;
478 			ret = -EISCONN;
479 			if (rx->sk.sk_state != RXRPC_UNBOUND)
480 				goto error;
481 			rx->exclusive = true;
482 			goto success;
483 
484 		case RXRPC_SECURITY_KEY:
485 			ret = -EINVAL;
486 			if (rx->key)
487 				goto error;
488 			ret = -EISCONN;
489 			if (rx->sk.sk_state != RXRPC_UNBOUND)
490 				goto error;
491 			ret = rxrpc_request_key(rx, optval, optlen);
492 			goto error;
493 
494 		case RXRPC_SECURITY_KEYRING:
495 			ret = -EINVAL;
496 			if (rx->key)
497 				goto error;
498 			ret = -EISCONN;
499 			if (rx->sk.sk_state != RXRPC_UNBOUND)
500 				goto error;
501 			ret = rxrpc_server_keyring(rx, optval, optlen);
502 			goto error;
503 
504 		case RXRPC_MIN_SECURITY_LEVEL:
505 			ret = -EINVAL;
506 			if (optlen != sizeof(unsigned int))
507 				goto error;
508 			ret = -EISCONN;
509 			if (rx->sk.sk_state != RXRPC_UNBOUND)
510 				goto error;
511 			ret = get_user(min_sec_level,
512 				       (unsigned int __user *) optval);
513 			if (ret < 0)
514 				goto error;
515 			ret = -EINVAL;
516 			if (min_sec_level > RXRPC_SECURITY_MAX)
517 				goto error;
518 			rx->min_sec_level = min_sec_level;
519 			goto success;
520 
521 		default:
522 			break;
523 		}
524 	}
525 
526 success:
527 	ret = 0;
528 error:
529 	release_sock(&rx->sk);
530 	return ret;
531 }
532 
533 /*
534  * permit an RxRPC socket to be polled
535  */
536 static unsigned int rxrpc_poll(struct file *file, struct socket *sock,
537 			       poll_table *wait)
538 {
539 	struct sock *sk = sock->sk;
540 	struct rxrpc_sock *rx = rxrpc_sk(sk);
541 	unsigned int mask;
542 
543 	sock_poll_wait(file, sk_sleep(sk), wait);
544 	mask = 0;
545 
546 	/* the socket is readable if there are any messages waiting on the Rx
547 	 * queue */
548 	if (!list_empty(&rx->recvmsg_q))
549 		mask |= POLLIN | POLLRDNORM;
550 
551 	/* the socket is writable if there is space to add new data to the
552 	 * socket; there is no guarantee that any particular call in progress
553 	 * on the socket may have space in the Tx ACK window */
554 	if (rxrpc_writable(sk))
555 		mask |= POLLOUT | POLLWRNORM;
556 
557 	return mask;
558 }
559 
560 /*
561  * create an RxRPC socket
562  */
563 static int rxrpc_create(struct net *net, struct socket *sock, int protocol,
564 			int kern)
565 {
566 	struct rxrpc_sock *rx;
567 	struct sock *sk;
568 
569 	_enter("%p,%d", sock, protocol);
570 
571 	if (!net_eq(net, &init_net))
572 		return -EAFNOSUPPORT;
573 
574 	/* we support transport protocol UDP/UDP6 only */
575 	if (protocol != PF_INET &&
576 	    IS_ENABLED(CONFIG_AF_RXRPC_IPV6) && protocol != PF_INET6)
577 		return -EPROTONOSUPPORT;
578 
579 	if (sock->type != SOCK_DGRAM)
580 		return -ESOCKTNOSUPPORT;
581 
582 	sock->ops = &rxrpc_rpc_ops;
583 	sock->state = SS_UNCONNECTED;
584 
585 	sk = sk_alloc(net, PF_RXRPC, GFP_KERNEL, &rxrpc_proto, kern);
586 	if (!sk)
587 		return -ENOMEM;
588 
589 	sock_init_data(sock, sk);
590 	sock_set_flag(sk, SOCK_RCU_FREE);
591 	sk->sk_state		= RXRPC_UNBOUND;
592 	sk->sk_write_space	= rxrpc_write_space;
593 	sk->sk_max_ack_backlog	= 0;
594 	sk->sk_destruct		= rxrpc_sock_destructor;
595 
596 	rx = rxrpc_sk(sk);
597 	rx->family = protocol;
598 	rx->calls = RB_ROOT;
599 
600 	spin_lock_init(&rx->incoming_lock);
601 	INIT_LIST_HEAD(&rx->sock_calls);
602 	INIT_LIST_HEAD(&rx->to_be_accepted);
603 	INIT_LIST_HEAD(&rx->recvmsg_q);
604 	rwlock_init(&rx->recvmsg_lock);
605 	rwlock_init(&rx->call_lock);
606 	memset(&rx->srx, 0, sizeof(rx->srx));
607 
608 	_leave(" = 0 [%p]", rx);
609 	return 0;
610 }
611 
612 /*
613  * Kill all the calls on a socket and shut it down.
614  */
615 static int rxrpc_shutdown(struct socket *sock, int flags)
616 {
617 	struct sock *sk = sock->sk;
618 	struct rxrpc_sock *rx = rxrpc_sk(sk);
619 	int ret = 0;
620 
621 	_enter("%p,%d", sk, flags);
622 
623 	if (flags != SHUT_RDWR)
624 		return -EOPNOTSUPP;
625 	if (sk->sk_state == RXRPC_CLOSE)
626 		return -ESHUTDOWN;
627 
628 	lock_sock(sk);
629 
630 	spin_lock_bh(&sk->sk_receive_queue.lock);
631 	if (sk->sk_state < RXRPC_CLOSE) {
632 		sk->sk_state = RXRPC_CLOSE;
633 		sk->sk_shutdown = SHUTDOWN_MASK;
634 	} else {
635 		ret = -ESHUTDOWN;
636 	}
637 	spin_unlock_bh(&sk->sk_receive_queue.lock);
638 
639 	rxrpc_discard_prealloc(rx);
640 
641 	release_sock(sk);
642 	return ret;
643 }
644 
645 /*
646  * RxRPC socket destructor
647  */
648 static void rxrpc_sock_destructor(struct sock *sk)
649 {
650 	_enter("%p", sk);
651 
652 	rxrpc_purge_queue(&sk->sk_receive_queue);
653 
654 	WARN_ON(atomic_read(&sk->sk_wmem_alloc));
655 	WARN_ON(!sk_unhashed(sk));
656 	WARN_ON(sk->sk_socket);
657 
658 	if (!sock_flag(sk, SOCK_DEAD)) {
659 		printk("Attempt to release alive rxrpc socket: %p\n", sk);
660 		return;
661 	}
662 }
663 
664 /*
665  * release an RxRPC socket
666  */
667 static int rxrpc_release_sock(struct sock *sk)
668 {
669 	struct rxrpc_sock *rx = rxrpc_sk(sk);
670 
671 	_enter("%p{%d,%d}", sk, sk->sk_state, atomic_read(&sk->sk_refcnt));
672 
673 	/* declare the socket closed for business */
674 	sock_orphan(sk);
675 	sk->sk_shutdown = SHUTDOWN_MASK;
676 
677 	spin_lock_bh(&sk->sk_receive_queue.lock);
678 	sk->sk_state = RXRPC_CLOSE;
679 	spin_unlock_bh(&sk->sk_receive_queue.lock);
680 
681 	if (rx->local && rcu_access_pointer(rx->local->service) == rx) {
682 		write_lock(&rx->local->services_lock);
683 		rcu_assign_pointer(rx->local->service, NULL);
684 		write_unlock(&rx->local->services_lock);
685 	}
686 
687 	/* try to flush out this socket */
688 	rxrpc_discard_prealloc(rx);
689 	rxrpc_release_calls_on_socket(rx);
690 	flush_workqueue(rxrpc_workqueue);
691 	rxrpc_purge_queue(&sk->sk_receive_queue);
692 
693 	rxrpc_put_local(rx->local);
694 	rx->local = NULL;
695 	key_put(rx->key);
696 	rx->key = NULL;
697 	key_put(rx->securities);
698 	rx->securities = NULL;
699 	sock_put(sk);
700 
701 	_leave(" = 0");
702 	return 0;
703 }
704 
705 /*
706  * release an RxRPC BSD socket on close() or equivalent
707  */
708 static int rxrpc_release(struct socket *sock)
709 {
710 	struct sock *sk = sock->sk;
711 
712 	_enter("%p{%p}", sock, sk);
713 
714 	if (!sk)
715 		return 0;
716 
717 	sock->sk = NULL;
718 
719 	return rxrpc_release_sock(sk);
720 }
721 
722 /*
723  * RxRPC network protocol
724  */
725 static const struct proto_ops rxrpc_rpc_ops = {
726 	.family		= PF_RXRPC,
727 	.owner		= THIS_MODULE,
728 	.release	= rxrpc_release,
729 	.bind		= rxrpc_bind,
730 	.connect	= rxrpc_connect,
731 	.socketpair	= sock_no_socketpair,
732 	.accept		= sock_no_accept,
733 	.getname	= sock_no_getname,
734 	.poll		= rxrpc_poll,
735 	.ioctl		= sock_no_ioctl,
736 	.listen		= rxrpc_listen,
737 	.shutdown	= rxrpc_shutdown,
738 	.setsockopt	= rxrpc_setsockopt,
739 	.getsockopt	= sock_no_getsockopt,
740 	.sendmsg	= rxrpc_sendmsg,
741 	.recvmsg	= rxrpc_recvmsg,
742 	.mmap		= sock_no_mmap,
743 	.sendpage	= sock_no_sendpage,
744 };
745 
746 static struct proto rxrpc_proto = {
747 	.name		= "RXRPC",
748 	.owner		= THIS_MODULE,
749 	.obj_size	= sizeof(struct rxrpc_sock),
750 	.max_header	= sizeof(struct rxrpc_wire_header),
751 };
752 
753 static const struct net_proto_family rxrpc_family_ops = {
754 	.family	= PF_RXRPC,
755 	.create = rxrpc_create,
756 	.owner	= THIS_MODULE,
757 };
758 
759 /*
760  * initialise and register the RxRPC protocol
761  */
762 static int __init af_rxrpc_init(void)
763 {
764 	int ret = -1;
765 
766 	BUILD_BUG_ON(sizeof(struct rxrpc_skb_priv) > FIELD_SIZEOF(struct sk_buff, cb));
767 
768 	get_random_bytes(&rxrpc_epoch, sizeof(rxrpc_epoch));
769 	rxrpc_epoch |= RXRPC_RANDOM_EPOCH;
770 	get_random_bytes(&rxrpc_client_conn_ids.cur,
771 			 sizeof(rxrpc_client_conn_ids.cur));
772 	rxrpc_client_conn_ids.cur &= 0x3fffffff;
773 	if (rxrpc_client_conn_ids.cur == 0)
774 		rxrpc_client_conn_ids.cur = 1;
775 
776 	ret = -ENOMEM;
777 	rxrpc_call_jar = kmem_cache_create(
778 		"rxrpc_call_jar", sizeof(struct rxrpc_call), 0,
779 		SLAB_HWCACHE_ALIGN, NULL);
780 	if (!rxrpc_call_jar) {
781 		pr_notice("Failed to allocate call jar\n");
782 		goto error_call_jar;
783 	}
784 
785 	rxrpc_workqueue = alloc_workqueue("krxrpcd", 0, 1);
786 	if (!rxrpc_workqueue) {
787 		pr_notice("Failed to allocate work queue\n");
788 		goto error_work_queue;
789 	}
790 
791 	ret = rxrpc_init_security();
792 	if (ret < 0) {
793 		pr_crit("Cannot initialise security\n");
794 		goto error_security;
795 	}
796 
797 	ret = proto_register(&rxrpc_proto, 1);
798 	if (ret < 0) {
799 		pr_crit("Cannot register protocol\n");
800 		goto error_proto;
801 	}
802 
803 	ret = sock_register(&rxrpc_family_ops);
804 	if (ret < 0) {
805 		pr_crit("Cannot register socket family\n");
806 		goto error_sock;
807 	}
808 
809 	ret = register_key_type(&key_type_rxrpc);
810 	if (ret < 0) {
811 		pr_crit("Cannot register client key type\n");
812 		goto error_key_type;
813 	}
814 
815 	ret = register_key_type(&key_type_rxrpc_s);
816 	if (ret < 0) {
817 		pr_crit("Cannot register server key type\n");
818 		goto error_key_type_s;
819 	}
820 
821 	ret = rxrpc_sysctl_init();
822 	if (ret < 0) {
823 		pr_crit("Cannot register sysctls\n");
824 		goto error_sysctls;
825 	}
826 
827 #ifdef CONFIG_PROC_FS
828 	proc_create("rxrpc_calls", 0, init_net.proc_net, &rxrpc_call_seq_fops);
829 	proc_create("rxrpc_conns", 0, init_net.proc_net,
830 		    &rxrpc_connection_seq_fops);
831 #endif
832 	return 0;
833 
834 error_sysctls:
835 	unregister_key_type(&key_type_rxrpc_s);
836 error_key_type_s:
837 	unregister_key_type(&key_type_rxrpc);
838 error_key_type:
839 	sock_unregister(PF_RXRPC);
840 error_sock:
841 	proto_unregister(&rxrpc_proto);
842 error_proto:
843 	rxrpc_exit_security();
844 error_security:
845 	destroy_workqueue(rxrpc_workqueue);
846 error_work_queue:
847 	kmem_cache_destroy(rxrpc_call_jar);
848 error_call_jar:
849 	return ret;
850 }
851 
852 /*
853  * unregister the RxRPC protocol
854  */
855 static void __exit af_rxrpc_exit(void)
856 {
857 	_enter("");
858 	rxrpc_sysctl_exit();
859 	unregister_key_type(&key_type_rxrpc_s);
860 	unregister_key_type(&key_type_rxrpc);
861 	sock_unregister(PF_RXRPC);
862 	proto_unregister(&rxrpc_proto);
863 	rxrpc_destroy_all_calls();
864 	rxrpc_destroy_all_connections();
865 	ASSERTCMP(atomic_read(&rxrpc_n_tx_skbs), ==, 0);
866 	ASSERTCMP(atomic_read(&rxrpc_n_rx_skbs), ==, 0);
867 	rxrpc_destroy_all_locals();
868 
869 	remove_proc_entry("rxrpc_conns", init_net.proc_net);
870 	remove_proc_entry("rxrpc_calls", init_net.proc_net);
871 	destroy_workqueue(rxrpc_workqueue);
872 	rxrpc_exit_security();
873 	kmem_cache_destroy(rxrpc_call_jar);
874 	_leave("");
875 }
876 
877 module_init(af_rxrpc_init);
878 module_exit(af_rxrpc_exit);
879