xref: /openbmc/linux/net/rxrpc/af_rxrpc.c (revision c8dbaa22)
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 /* current debugging ID */
42 atomic_t rxrpc_debug_id;
43 
44 /* count of skbs currently in use */
45 atomic_t rxrpc_n_tx_skbs, rxrpc_n_rx_skbs;
46 
47 struct workqueue_struct *rxrpc_workqueue;
48 
49 static void rxrpc_sock_destructor(struct sock *);
50 
51 /*
52  * see if an RxRPC socket is currently writable
53  */
54 static inline int rxrpc_writable(struct sock *sk)
55 {
56 	return refcount_read(&sk->sk_wmem_alloc) < (size_t) sk->sk_sndbuf;
57 }
58 
59 /*
60  * wait for write bufferage to become available
61  */
62 static void rxrpc_write_space(struct sock *sk)
63 {
64 	_enter("%p", sk);
65 	rcu_read_lock();
66 	if (rxrpc_writable(sk)) {
67 		struct socket_wq *wq = rcu_dereference(sk->sk_wq);
68 
69 		if (skwq_has_sleeper(wq))
70 			wake_up_interruptible(&wq->wait);
71 		sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
72 	}
73 	rcu_read_unlock();
74 }
75 
76 /*
77  * validate an RxRPC address
78  */
79 static int rxrpc_validate_address(struct rxrpc_sock *rx,
80 				  struct sockaddr_rxrpc *srx,
81 				  int len)
82 {
83 	unsigned int tail;
84 
85 	if (len < sizeof(struct sockaddr_rxrpc))
86 		return -EINVAL;
87 
88 	if (srx->srx_family != AF_RXRPC)
89 		return -EAFNOSUPPORT;
90 
91 	if (srx->transport_type != SOCK_DGRAM)
92 		return -ESOCKTNOSUPPORT;
93 
94 	len -= offsetof(struct sockaddr_rxrpc, transport);
95 	if (srx->transport_len < sizeof(sa_family_t) ||
96 	    srx->transport_len > len)
97 		return -EINVAL;
98 
99 	if (srx->transport.family != rx->family)
100 		return -EAFNOSUPPORT;
101 
102 	switch (srx->transport.family) {
103 	case AF_INET:
104 		if (srx->transport_len < sizeof(struct sockaddr_in))
105 			return -EINVAL;
106 		tail = offsetof(struct sockaddr_rxrpc, transport.sin.__pad);
107 		break;
108 
109 #ifdef CONFIG_AF_RXRPC_IPV6
110 	case AF_INET6:
111 		if (srx->transport_len < sizeof(struct sockaddr_in6))
112 			return -EINVAL;
113 		tail = offsetof(struct sockaddr_rxrpc, transport) +
114 			sizeof(struct sockaddr_in6);
115 		break;
116 #endif
117 
118 	default:
119 		return -EAFNOSUPPORT;
120 	}
121 
122 	if (tail < len)
123 		memset((void *)srx + tail, 0, len - tail);
124 	_debug("INET: %pISp", &srx->transport);
125 	return 0;
126 }
127 
128 /*
129  * bind a local address to an RxRPC socket
130  */
131 static int rxrpc_bind(struct socket *sock, struct sockaddr *saddr, int len)
132 {
133 	struct sockaddr_rxrpc *srx = (struct sockaddr_rxrpc *)saddr;
134 	struct rxrpc_local *local;
135 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
136 	u16 service_id = srx->srx_service;
137 	int ret;
138 
139 	_enter("%p,%p,%d", rx, saddr, len);
140 
141 	ret = rxrpc_validate_address(rx, srx, len);
142 	if (ret < 0)
143 		goto error;
144 
145 	lock_sock(&rx->sk);
146 
147 	switch (rx->sk.sk_state) {
148 	case RXRPC_UNBOUND:
149 		rx->srx = *srx;
150 		local = rxrpc_lookup_local(sock_net(&rx->sk), &rx->srx);
151 		if (IS_ERR(local)) {
152 			ret = PTR_ERR(local);
153 			goto error_unlock;
154 		}
155 
156 		if (service_id) {
157 			write_lock(&local->services_lock);
158 			if (rcu_access_pointer(local->service))
159 				goto service_in_use;
160 			rx->local = local;
161 			rcu_assign_pointer(local->service, rx);
162 			write_unlock(&local->services_lock);
163 
164 			rx->sk.sk_state = RXRPC_SERVER_BOUND;
165 		} else {
166 			rx->local = local;
167 			rx->sk.sk_state = RXRPC_CLIENT_BOUND;
168 		}
169 		break;
170 
171 	case RXRPC_SERVER_BOUND:
172 		ret = -EINVAL;
173 		if (service_id == 0)
174 			goto error_unlock;
175 		ret = -EADDRINUSE;
176 		if (service_id == rx->srx.srx_service)
177 			goto error_unlock;
178 		ret = -EINVAL;
179 		srx->srx_service = rx->srx.srx_service;
180 		if (memcmp(srx, &rx->srx, sizeof(*srx)) != 0)
181 			goto error_unlock;
182 		rx->second_service = service_id;
183 		rx->sk.sk_state = RXRPC_SERVER_BOUND2;
184 		break;
185 
186 	default:
187 		ret = -EINVAL;
188 		goto error_unlock;
189 	}
190 
191 	release_sock(&rx->sk);
192 	_leave(" = 0");
193 	return 0;
194 
195 service_in_use:
196 	write_unlock(&local->services_lock);
197 	rxrpc_put_local(local);
198 	ret = -EADDRINUSE;
199 error_unlock:
200 	release_sock(&rx->sk);
201 error:
202 	_leave(" = %d", ret);
203 	return ret;
204 }
205 
206 /*
207  * set the number of pending calls permitted on a listening socket
208  */
209 static int rxrpc_listen(struct socket *sock, int backlog)
210 {
211 	struct sock *sk = sock->sk;
212 	struct rxrpc_sock *rx = rxrpc_sk(sk);
213 	unsigned int max, old;
214 	int ret;
215 
216 	_enter("%p,%d", rx, backlog);
217 
218 	lock_sock(&rx->sk);
219 
220 	switch (rx->sk.sk_state) {
221 	case RXRPC_UNBOUND:
222 		ret = -EADDRNOTAVAIL;
223 		break;
224 	case RXRPC_SERVER_BOUND:
225 	case RXRPC_SERVER_BOUND2:
226 		ASSERT(rx->local != NULL);
227 		max = READ_ONCE(rxrpc_max_backlog);
228 		ret = -EINVAL;
229 		if (backlog == INT_MAX)
230 			backlog = max;
231 		else if (backlog < 0 || backlog > max)
232 			break;
233 		old = sk->sk_max_ack_backlog;
234 		sk->sk_max_ack_backlog = backlog;
235 		ret = rxrpc_service_prealloc(rx, GFP_KERNEL);
236 		if (ret == 0)
237 			rx->sk.sk_state = RXRPC_SERVER_LISTENING;
238 		else
239 			sk->sk_max_ack_backlog = old;
240 		break;
241 	case RXRPC_SERVER_LISTENING:
242 		if (backlog == 0) {
243 			rx->sk.sk_state = RXRPC_SERVER_LISTEN_DISABLED;
244 			sk->sk_max_ack_backlog = 0;
245 			rxrpc_discard_prealloc(rx);
246 			ret = 0;
247 			break;
248 		}
249 	default:
250 		ret = -EBUSY;
251 		break;
252 	}
253 
254 	release_sock(&rx->sk);
255 	_leave(" = %d", ret);
256 	return ret;
257 }
258 
259 /**
260  * rxrpc_kernel_begin_call - Allow a kernel service to begin a call
261  * @sock: The socket on which to make the call
262  * @srx: The address of the peer to contact
263  * @key: The security context to use (defaults to socket setting)
264  * @user_call_ID: The ID to use
265  * @tx_total_len: Total length of data to transmit during the call (or -1)
266  * @gfp: The allocation constraints
267  * @notify_rx: Where to send notifications instead of socket queue
268  *
269  * Allow a kernel service to begin a call on the nominated socket.  This just
270  * sets up all the internal tracking structures and allocates connection and
271  * call IDs as appropriate.  The call to be used is returned.
272  *
273  * The default socket destination address and security may be overridden by
274  * supplying @srx and @key.
275  */
276 struct rxrpc_call *rxrpc_kernel_begin_call(struct socket *sock,
277 					   struct sockaddr_rxrpc *srx,
278 					   struct key *key,
279 					   unsigned long user_call_ID,
280 					   s64 tx_total_len,
281 					   gfp_t gfp,
282 					   rxrpc_notify_rx_t notify_rx)
283 {
284 	struct rxrpc_conn_parameters cp;
285 	struct rxrpc_call *call;
286 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
287 	int ret;
288 
289 	_enter(",,%x,%lx", key_serial(key), user_call_ID);
290 
291 	ret = rxrpc_validate_address(rx, srx, sizeof(*srx));
292 	if (ret < 0)
293 		return ERR_PTR(ret);
294 
295 	lock_sock(&rx->sk);
296 
297 	if (!key)
298 		key = rx->key;
299 	if (key && !key->payload.data[0])
300 		key = NULL; /* a no-security key */
301 
302 	memset(&cp, 0, sizeof(cp));
303 	cp.local		= rx->local;
304 	cp.key			= key;
305 	cp.security_level	= 0;
306 	cp.exclusive		= false;
307 	cp.service_id		= srx->srx_service;
308 	call = rxrpc_new_client_call(rx, &cp, srx, user_call_ID, tx_total_len,
309 				     gfp);
310 	/* The socket has been unlocked. */
311 	if (!IS_ERR(call))
312 		call->notify_rx = notify_rx;
313 
314 	mutex_unlock(&call->user_mutex);
315 	_leave(" = %p", call);
316 	return call;
317 }
318 EXPORT_SYMBOL(rxrpc_kernel_begin_call);
319 
320 /**
321  * rxrpc_kernel_end_call - Allow a kernel service to end a call it was using
322  * @sock: The socket the call is on
323  * @call: The call to end
324  *
325  * Allow a kernel service to end a call it was using.  The call must be
326  * complete before this is called (the call should be aborted if necessary).
327  */
328 void rxrpc_kernel_end_call(struct socket *sock, struct rxrpc_call *call)
329 {
330 	_enter("%d{%d}", call->debug_id, atomic_read(&call->usage));
331 
332 	mutex_lock(&call->user_mutex);
333 	rxrpc_release_call(rxrpc_sk(sock->sk), call);
334 	mutex_unlock(&call->user_mutex);
335 	rxrpc_put_call(call, rxrpc_call_put_kernel);
336 }
337 EXPORT_SYMBOL(rxrpc_kernel_end_call);
338 
339 /**
340  * rxrpc_kernel_new_call_notification - Get notifications of new calls
341  * @sock: The socket to intercept received messages on
342  * @notify_new_call: Function to be called when new calls appear
343  * @discard_new_call: Function to discard preallocated calls
344  *
345  * Allow a kernel service to be given notifications about new calls.
346  */
347 void rxrpc_kernel_new_call_notification(
348 	struct socket *sock,
349 	rxrpc_notify_new_call_t notify_new_call,
350 	rxrpc_discard_new_call_t discard_new_call)
351 {
352 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
353 
354 	rx->notify_new_call = notify_new_call;
355 	rx->discard_new_call = discard_new_call;
356 }
357 EXPORT_SYMBOL(rxrpc_kernel_new_call_notification);
358 
359 /*
360  * connect an RxRPC socket
361  * - this just targets it at a specific destination; no actual connection
362  *   negotiation takes place
363  */
364 static int rxrpc_connect(struct socket *sock, struct sockaddr *addr,
365 			 int addr_len, int flags)
366 {
367 	struct sockaddr_rxrpc *srx = (struct sockaddr_rxrpc *)addr;
368 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
369 	int ret;
370 
371 	_enter("%p,%p,%d,%d", rx, addr, addr_len, flags);
372 
373 	ret = rxrpc_validate_address(rx, srx, addr_len);
374 	if (ret < 0) {
375 		_leave(" = %d [bad addr]", ret);
376 		return ret;
377 	}
378 
379 	lock_sock(&rx->sk);
380 
381 	ret = -EISCONN;
382 	if (test_bit(RXRPC_SOCK_CONNECTED, &rx->flags))
383 		goto error;
384 
385 	switch (rx->sk.sk_state) {
386 	case RXRPC_UNBOUND:
387 		rx->sk.sk_state = RXRPC_CLIENT_UNBOUND;
388 	case RXRPC_CLIENT_UNBOUND:
389 	case RXRPC_CLIENT_BOUND:
390 		break;
391 	default:
392 		ret = -EBUSY;
393 		goto error;
394 	}
395 
396 	rx->connect_srx = *srx;
397 	set_bit(RXRPC_SOCK_CONNECTED, &rx->flags);
398 	ret = 0;
399 
400 error:
401 	release_sock(&rx->sk);
402 	return ret;
403 }
404 
405 /*
406  * send a message through an RxRPC socket
407  * - in a client this does a number of things:
408  *   - finds/sets up a connection for the security specified (if any)
409  *   - initiates a call (ID in control data)
410  *   - ends the request phase of a call (if MSG_MORE is not set)
411  *   - sends a call data packet
412  *   - may send an abort (abort code in control data)
413  */
414 static int rxrpc_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
415 {
416 	struct rxrpc_local *local;
417 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
418 	int ret;
419 
420 	_enter(",{%d},,%zu", rx->sk.sk_state, len);
421 
422 	if (m->msg_flags & MSG_OOB)
423 		return -EOPNOTSUPP;
424 
425 	if (m->msg_name) {
426 		ret = rxrpc_validate_address(rx, m->msg_name, m->msg_namelen);
427 		if (ret < 0) {
428 			_leave(" = %d [bad addr]", ret);
429 			return ret;
430 		}
431 	}
432 
433 	lock_sock(&rx->sk);
434 
435 	switch (rx->sk.sk_state) {
436 	case RXRPC_UNBOUND:
437 		rx->srx.srx_family = AF_RXRPC;
438 		rx->srx.srx_service = 0;
439 		rx->srx.transport_type = SOCK_DGRAM;
440 		rx->srx.transport.family = rx->family;
441 		switch (rx->family) {
442 		case AF_INET:
443 			rx->srx.transport_len = sizeof(struct sockaddr_in);
444 			break;
445 #ifdef CONFIG_AF_RXRPC_IPV6
446 		case AF_INET6:
447 			rx->srx.transport_len = sizeof(struct sockaddr_in6);
448 			break;
449 #endif
450 		default:
451 			ret = -EAFNOSUPPORT;
452 			goto error_unlock;
453 		}
454 		local = rxrpc_lookup_local(sock_net(sock->sk), &rx->srx);
455 		if (IS_ERR(local)) {
456 			ret = PTR_ERR(local);
457 			goto error_unlock;
458 		}
459 
460 		rx->local = local;
461 		rx->sk.sk_state = RXRPC_CLIENT_UNBOUND;
462 		/* Fall through */
463 
464 	case RXRPC_CLIENT_UNBOUND:
465 	case RXRPC_CLIENT_BOUND:
466 		if (!m->msg_name &&
467 		    test_bit(RXRPC_SOCK_CONNECTED, &rx->flags)) {
468 			m->msg_name = &rx->connect_srx;
469 			m->msg_namelen = sizeof(rx->connect_srx);
470 		}
471 	case RXRPC_SERVER_BOUND:
472 	case RXRPC_SERVER_LISTENING:
473 		ret = rxrpc_do_sendmsg(rx, m, len);
474 		/* The socket has been unlocked */
475 		goto out;
476 	default:
477 		ret = -EINVAL;
478 		goto error_unlock;
479 	}
480 
481 error_unlock:
482 	release_sock(&rx->sk);
483 out:
484 	_leave(" = %d", ret);
485 	return ret;
486 }
487 
488 /*
489  * set RxRPC socket options
490  */
491 static int rxrpc_setsockopt(struct socket *sock, int level, int optname,
492 			    char __user *optval, unsigned int optlen)
493 {
494 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
495 	unsigned int min_sec_level;
496 	u16 service_upgrade[2];
497 	int ret;
498 
499 	_enter(",%d,%d,,%d", level, optname, optlen);
500 
501 	lock_sock(&rx->sk);
502 	ret = -EOPNOTSUPP;
503 
504 	if (level == SOL_RXRPC) {
505 		switch (optname) {
506 		case RXRPC_EXCLUSIVE_CONNECTION:
507 			ret = -EINVAL;
508 			if (optlen != 0)
509 				goto error;
510 			ret = -EISCONN;
511 			if (rx->sk.sk_state != RXRPC_UNBOUND)
512 				goto error;
513 			rx->exclusive = true;
514 			goto success;
515 
516 		case RXRPC_SECURITY_KEY:
517 			ret = -EINVAL;
518 			if (rx->key)
519 				goto error;
520 			ret = -EISCONN;
521 			if (rx->sk.sk_state != RXRPC_UNBOUND)
522 				goto error;
523 			ret = rxrpc_request_key(rx, optval, optlen);
524 			goto error;
525 
526 		case RXRPC_SECURITY_KEYRING:
527 			ret = -EINVAL;
528 			if (rx->key)
529 				goto error;
530 			ret = -EISCONN;
531 			if (rx->sk.sk_state != RXRPC_UNBOUND)
532 				goto error;
533 			ret = rxrpc_server_keyring(rx, optval, optlen);
534 			goto error;
535 
536 		case RXRPC_MIN_SECURITY_LEVEL:
537 			ret = -EINVAL;
538 			if (optlen != sizeof(unsigned int))
539 				goto error;
540 			ret = -EISCONN;
541 			if (rx->sk.sk_state != RXRPC_UNBOUND)
542 				goto error;
543 			ret = get_user(min_sec_level,
544 				       (unsigned int __user *) optval);
545 			if (ret < 0)
546 				goto error;
547 			ret = -EINVAL;
548 			if (min_sec_level > RXRPC_SECURITY_MAX)
549 				goto error;
550 			rx->min_sec_level = min_sec_level;
551 			goto success;
552 
553 		case RXRPC_UPGRADEABLE_SERVICE:
554 			ret = -EINVAL;
555 			if (optlen != sizeof(service_upgrade) ||
556 			    rx->service_upgrade.from != 0)
557 				goto error;
558 			ret = -EISCONN;
559 			if (rx->sk.sk_state != RXRPC_SERVER_BOUND2)
560 				goto error;
561 			ret = -EFAULT;
562 			if (copy_from_user(service_upgrade, optval,
563 					   sizeof(service_upgrade)) != 0)
564 				goto error;
565 			ret = -EINVAL;
566 			if ((service_upgrade[0] != rx->srx.srx_service ||
567 			     service_upgrade[1] != rx->second_service) &&
568 			    (service_upgrade[0] != rx->second_service ||
569 			     service_upgrade[1] != rx->srx.srx_service))
570 				goto error;
571 			rx->service_upgrade.from = service_upgrade[0];
572 			rx->service_upgrade.to = service_upgrade[1];
573 			goto success;
574 
575 		default:
576 			break;
577 		}
578 	}
579 
580 success:
581 	ret = 0;
582 error:
583 	release_sock(&rx->sk);
584 	return ret;
585 }
586 
587 /*
588  * Get socket options.
589  */
590 static int rxrpc_getsockopt(struct socket *sock, int level, int optname,
591 			    char __user *optval, int __user *_optlen)
592 {
593 	int optlen;
594 
595 	if (level != SOL_RXRPC)
596 		return -EOPNOTSUPP;
597 
598 	if (get_user(optlen, _optlen))
599 		return -EFAULT;
600 
601 	switch (optname) {
602 	case RXRPC_SUPPORTED_CMSG:
603 		if (optlen < sizeof(int))
604 			return -ETOOSMALL;
605 		if (put_user(RXRPC__SUPPORTED - 1, (int __user *)optval) ||
606 		    put_user(sizeof(int), _optlen))
607 			return -EFAULT;
608 		return 0;
609 
610 	default:
611 		return -EOPNOTSUPP;
612 	}
613 }
614 
615 /*
616  * permit an RxRPC socket to be polled
617  */
618 static unsigned int rxrpc_poll(struct file *file, struct socket *sock,
619 			       poll_table *wait)
620 {
621 	struct sock *sk = sock->sk;
622 	struct rxrpc_sock *rx = rxrpc_sk(sk);
623 	unsigned int mask;
624 
625 	sock_poll_wait(file, sk_sleep(sk), wait);
626 	mask = 0;
627 
628 	/* the socket is readable if there are any messages waiting on the Rx
629 	 * queue */
630 	if (!list_empty(&rx->recvmsg_q))
631 		mask |= POLLIN | POLLRDNORM;
632 
633 	/* the socket is writable if there is space to add new data to the
634 	 * socket; there is no guarantee that any particular call in progress
635 	 * on the socket may have space in the Tx ACK window */
636 	if (rxrpc_writable(sk))
637 		mask |= POLLOUT | POLLWRNORM;
638 
639 	return mask;
640 }
641 
642 /*
643  * create an RxRPC socket
644  */
645 static int rxrpc_create(struct net *net, struct socket *sock, int protocol,
646 			int kern)
647 {
648 	struct rxrpc_sock *rx;
649 	struct sock *sk;
650 
651 	_enter("%p,%d", sock, protocol);
652 
653 	/* we support transport protocol UDP/UDP6 only */
654 	if (protocol != PF_INET &&
655 	    IS_ENABLED(CONFIG_AF_RXRPC_IPV6) && protocol != PF_INET6)
656 		return -EPROTONOSUPPORT;
657 
658 	if (sock->type != SOCK_DGRAM)
659 		return -ESOCKTNOSUPPORT;
660 
661 	sock->ops = &rxrpc_rpc_ops;
662 	sock->state = SS_UNCONNECTED;
663 
664 	sk = sk_alloc(net, PF_RXRPC, GFP_KERNEL, &rxrpc_proto, kern);
665 	if (!sk)
666 		return -ENOMEM;
667 
668 	sock_init_data(sock, sk);
669 	sock_set_flag(sk, SOCK_RCU_FREE);
670 	sk->sk_state		= RXRPC_UNBOUND;
671 	sk->sk_write_space	= rxrpc_write_space;
672 	sk->sk_max_ack_backlog	= 0;
673 	sk->sk_destruct		= rxrpc_sock_destructor;
674 
675 	rx = rxrpc_sk(sk);
676 	rx->family = protocol;
677 	rx->calls = RB_ROOT;
678 
679 	spin_lock_init(&rx->incoming_lock);
680 	INIT_LIST_HEAD(&rx->sock_calls);
681 	INIT_LIST_HEAD(&rx->to_be_accepted);
682 	INIT_LIST_HEAD(&rx->recvmsg_q);
683 	rwlock_init(&rx->recvmsg_lock);
684 	rwlock_init(&rx->call_lock);
685 	memset(&rx->srx, 0, sizeof(rx->srx));
686 
687 	_leave(" = 0 [%p]", rx);
688 	return 0;
689 }
690 
691 /*
692  * Kill all the calls on a socket and shut it down.
693  */
694 static int rxrpc_shutdown(struct socket *sock, int flags)
695 {
696 	struct sock *sk = sock->sk;
697 	struct rxrpc_sock *rx = rxrpc_sk(sk);
698 	int ret = 0;
699 
700 	_enter("%p,%d", sk, flags);
701 
702 	if (flags != SHUT_RDWR)
703 		return -EOPNOTSUPP;
704 	if (sk->sk_state == RXRPC_CLOSE)
705 		return -ESHUTDOWN;
706 
707 	lock_sock(sk);
708 
709 	spin_lock_bh(&sk->sk_receive_queue.lock);
710 	if (sk->sk_state < RXRPC_CLOSE) {
711 		sk->sk_state = RXRPC_CLOSE;
712 		sk->sk_shutdown = SHUTDOWN_MASK;
713 	} else {
714 		ret = -ESHUTDOWN;
715 	}
716 	spin_unlock_bh(&sk->sk_receive_queue.lock);
717 
718 	rxrpc_discard_prealloc(rx);
719 
720 	release_sock(sk);
721 	return ret;
722 }
723 
724 /*
725  * RxRPC socket destructor
726  */
727 static void rxrpc_sock_destructor(struct sock *sk)
728 {
729 	_enter("%p", sk);
730 
731 	rxrpc_purge_queue(&sk->sk_receive_queue);
732 
733 	WARN_ON(refcount_read(&sk->sk_wmem_alloc));
734 	WARN_ON(!sk_unhashed(sk));
735 	WARN_ON(sk->sk_socket);
736 
737 	if (!sock_flag(sk, SOCK_DEAD)) {
738 		printk("Attempt to release alive rxrpc socket: %p\n", sk);
739 		return;
740 	}
741 }
742 
743 /*
744  * release an RxRPC socket
745  */
746 static int rxrpc_release_sock(struct sock *sk)
747 {
748 	struct rxrpc_sock *rx = rxrpc_sk(sk);
749 
750 	_enter("%p{%d,%d}", sk, sk->sk_state, refcount_read(&sk->sk_refcnt));
751 
752 	/* declare the socket closed for business */
753 	sock_orphan(sk);
754 	sk->sk_shutdown = SHUTDOWN_MASK;
755 
756 	spin_lock_bh(&sk->sk_receive_queue.lock);
757 	sk->sk_state = RXRPC_CLOSE;
758 	spin_unlock_bh(&sk->sk_receive_queue.lock);
759 
760 	if (rx->local && rcu_access_pointer(rx->local->service) == rx) {
761 		write_lock(&rx->local->services_lock);
762 		rcu_assign_pointer(rx->local->service, NULL);
763 		write_unlock(&rx->local->services_lock);
764 	}
765 
766 	/* try to flush out this socket */
767 	rxrpc_discard_prealloc(rx);
768 	rxrpc_release_calls_on_socket(rx);
769 	flush_workqueue(rxrpc_workqueue);
770 	rxrpc_purge_queue(&sk->sk_receive_queue);
771 
772 	rxrpc_put_local(rx->local);
773 	rx->local = NULL;
774 	key_put(rx->key);
775 	rx->key = NULL;
776 	key_put(rx->securities);
777 	rx->securities = NULL;
778 	sock_put(sk);
779 
780 	_leave(" = 0");
781 	return 0;
782 }
783 
784 /*
785  * release an RxRPC BSD socket on close() or equivalent
786  */
787 static int rxrpc_release(struct socket *sock)
788 {
789 	struct sock *sk = sock->sk;
790 
791 	_enter("%p{%p}", sock, sk);
792 
793 	if (!sk)
794 		return 0;
795 
796 	sock->sk = NULL;
797 
798 	return rxrpc_release_sock(sk);
799 }
800 
801 /*
802  * RxRPC network protocol
803  */
804 static const struct proto_ops rxrpc_rpc_ops = {
805 	.family		= PF_RXRPC,
806 	.owner		= THIS_MODULE,
807 	.release	= rxrpc_release,
808 	.bind		= rxrpc_bind,
809 	.connect	= rxrpc_connect,
810 	.socketpair	= sock_no_socketpair,
811 	.accept		= sock_no_accept,
812 	.getname	= sock_no_getname,
813 	.poll		= rxrpc_poll,
814 	.ioctl		= sock_no_ioctl,
815 	.listen		= rxrpc_listen,
816 	.shutdown	= rxrpc_shutdown,
817 	.setsockopt	= rxrpc_setsockopt,
818 	.getsockopt	= rxrpc_getsockopt,
819 	.sendmsg	= rxrpc_sendmsg,
820 	.recvmsg	= rxrpc_recvmsg,
821 	.mmap		= sock_no_mmap,
822 	.sendpage	= sock_no_sendpage,
823 };
824 
825 static struct proto rxrpc_proto = {
826 	.name		= "RXRPC",
827 	.owner		= THIS_MODULE,
828 	.obj_size	= sizeof(struct rxrpc_sock),
829 	.max_header	= sizeof(struct rxrpc_wire_header),
830 };
831 
832 static const struct net_proto_family rxrpc_family_ops = {
833 	.family	= PF_RXRPC,
834 	.create = rxrpc_create,
835 	.owner	= THIS_MODULE,
836 };
837 
838 /*
839  * initialise and register the RxRPC protocol
840  */
841 static int __init af_rxrpc_init(void)
842 {
843 	int ret = -1;
844 	unsigned int tmp;
845 
846 	BUILD_BUG_ON(sizeof(struct rxrpc_skb_priv) > FIELD_SIZEOF(struct sk_buff, cb));
847 
848 	get_random_bytes(&tmp, sizeof(tmp));
849 	tmp &= 0x3fffffff;
850 	if (tmp == 0)
851 		tmp = 1;
852 	idr_set_cursor(&rxrpc_client_conn_ids, tmp);
853 
854 	ret = -ENOMEM;
855 	rxrpc_call_jar = kmem_cache_create(
856 		"rxrpc_call_jar", sizeof(struct rxrpc_call), 0,
857 		SLAB_HWCACHE_ALIGN, NULL);
858 	if (!rxrpc_call_jar) {
859 		pr_notice("Failed to allocate call jar\n");
860 		goto error_call_jar;
861 	}
862 
863 	rxrpc_workqueue = alloc_workqueue("krxrpcd", 0, 1);
864 	if (!rxrpc_workqueue) {
865 		pr_notice("Failed to allocate work queue\n");
866 		goto error_work_queue;
867 	}
868 
869 	ret = rxrpc_init_security();
870 	if (ret < 0) {
871 		pr_crit("Cannot initialise security\n");
872 		goto error_security;
873 	}
874 
875 	ret = register_pernet_subsys(&rxrpc_net_ops);
876 	if (ret)
877 		goto error_pernet;
878 
879 	ret = proto_register(&rxrpc_proto, 1);
880 	if (ret < 0) {
881 		pr_crit("Cannot register protocol\n");
882 		goto error_proto;
883 	}
884 
885 	ret = sock_register(&rxrpc_family_ops);
886 	if (ret < 0) {
887 		pr_crit("Cannot register socket family\n");
888 		goto error_sock;
889 	}
890 
891 	ret = register_key_type(&key_type_rxrpc);
892 	if (ret < 0) {
893 		pr_crit("Cannot register client key type\n");
894 		goto error_key_type;
895 	}
896 
897 	ret = register_key_type(&key_type_rxrpc_s);
898 	if (ret < 0) {
899 		pr_crit("Cannot register server key type\n");
900 		goto error_key_type_s;
901 	}
902 
903 	ret = rxrpc_sysctl_init();
904 	if (ret < 0) {
905 		pr_crit("Cannot register sysctls\n");
906 		goto error_sysctls;
907 	}
908 
909 	return 0;
910 
911 error_sysctls:
912 	unregister_key_type(&key_type_rxrpc_s);
913 error_key_type_s:
914 	unregister_key_type(&key_type_rxrpc);
915 error_key_type:
916 	sock_unregister(PF_RXRPC);
917 error_sock:
918 	proto_unregister(&rxrpc_proto);
919 error_proto:
920 	unregister_pernet_subsys(&rxrpc_net_ops);
921 error_pernet:
922 	rxrpc_exit_security();
923 error_security:
924 	destroy_workqueue(rxrpc_workqueue);
925 error_work_queue:
926 	kmem_cache_destroy(rxrpc_call_jar);
927 error_call_jar:
928 	return ret;
929 }
930 
931 /*
932  * unregister the RxRPC protocol
933  */
934 static void __exit af_rxrpc_exit(void)
935 {
936 	_enter("");
937 	rxrpc_sysctl_exit();
938 	unregister_key_type(&key_type_rxrpc_s);
939 	unregister_key_type(&key_type_rxrpc);
940 	sock_unregister(PF_RXRPC);
941 	proto_unregister(&rxrpc_proto);
942 	unregister_pernet_subsys(&rxrpc_net_ops);
943 	ASSERTCMP(atomic_read(&rxrpc_n_tx_skbs), ==, 0);
944 	ASSERTCMP(atomic_read(&rxrpc_n_rx_skbs), ==, 0);
945 
946 	/* Make sure the local and peer records pinned by any dying connections
947 	 * are released.
948 	 */
949 	rcu_barrier();
950 	rxrpc_destroy_client_conn_ids();
951 
952 	destroy_workqueue(rxrpc_workqueue);
953 	rxrpc_exit_security();
954 	kmem_cache_destroy(rxrpc_call_jar);
955 	_leave("");
956 }
957 
958 module_init(af_rxrpc_init);
959 module_exit(af_rxrpc_exit);
960