xref: /linux/net/rxrpc/af_rxrpc.c (revision b77e0ce62d63a761ffb7f7245a215a49f5921c2f)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* AF_RXRPC implementation
3  *
4  * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
5  * Written by David Howells (dhowells@redhat.com)
6  */
7 
8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9 
10 #include <linux/module.h>
11 #include <linux/kernel.h>
12 #include <linux/net.h>
13 #include <linux/slab.h>
14 #include <linux/skbuff.h>
15 #include <linux/random.h>
16 #include <linux/poll.h>
17 #include <linux/proc_fs.h>
18 #include <linux/key-type.h>
19 #include <net/net_namespace.h>
20 #include <net/sock.h>
21 #include <net/af_rxrpc.h>
22 #define CREATE_TRACE_POINTS
23 #include "ar-internal.h"
24 
25 MODULE_DESCRIPTION("RxRPC network protocol");
26 MODULE_AUTHOR("Red Hat, Inc.");
27 MODULE_LICENSE("GPL");
28 MODULE_ALIAS_NETPROTO(PF_RXRPC);
29 
30 unsigned int rxrpc_debug; // = RXRPC_DEBUG_KPROTO;
31 module_param_named(debug, rxrpc_debug, uint, 0644);
32 MODULE_PARM_DESC(debug, "RxRPC debugging mask");
33 
34 static struct proto rxrpc_proto;
35 static const struct proto_ops rxrpc_rpc_ops;
36 
37 /* current debugging ID */
38 atomic_t rxrpc_debug_id;
39 EXPORT_SYMBOL(rxrpc_debug_id);
40 
41 /* count of skbs currently in use */
42 atomic_t rxrpc_n_tx_skbs, rxrpc_n_rx_skbs;
43 
44 struct workqueue_struct *rxrpc_workqueue;
45 
46 static void rxrpc_sock_destructor(struct sock *);
47 
48 /*
49  * see if an RxRPC socket is currently writable
50  */
51 static inline int rxrpc_writable(struct sock *sk)
52 {
53 	return refcount_read(&sk->sk_wmem_alloc) < (size_t) sk->sk_sndbuf;
54 }
55 
56 /*
57  * wait for write bufferage to become available
58  */
59 static void rxrpc_write_space(struct sock *sk)
60 {
61 	_enter("%p", sk);
62 	rcu_read_lock();
63 	if (rxrpc_writable(sk)) {
64 		struct socket_wq *wq = rcu_dereference(sk->sk_wq);
65 
66 		if (skwq_has_sleeper(wq))
67 			wake_up_interruptible(&wq->wait);
68 		sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
69 	}
70 	rcu_read_unlock();
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 	unsigned int tail;
81 
82 	if (len < sizeof(struct sockaddr_rxrpc))
83 		return -EINVAL;
84 
85 	if (srx->srx_family != AF_RXRPC)
86 		return -EAFNOSUPPORT;
87 
88 	if (srx->transport_type != SOCK_DGRAM)
89 		return -ESOCKTNOSUPPORT;
90 
91 	len -= offsetof(struct sockaddr_rxrpc, transport);
92 	if (srx->transport_len < sizeof(sa_family_t) ||
93 	    srx->transport_len > len)
94 		return -EINVAL;
95 
96 	if (srx->transport.family != rx->family &&
97 	    srx->transport.family == AF_INET && rx->family != AF_INET6)
98 		return -EAFNOSUPPORT;
99 
100 	switch (srx->transport.family) {
101 	case AF_INET:
102 		if (srx->transport_len < sizeof(struct sockaddr_in))
103 			return -EINVAL;
104 		tail = offsetof(struct sockaddr_rxrpc, transport.sin.__pad);
105 		break;
106 
107 #ifdef CONFIG_AF_RXRPC_IPV6
108 	case AF_INET6:
109 		if (srx->transport_len < sizeof(struct sockaddr_in6))
110 			return -EINVAL;
111 		tail = offsetof(struct sockaddr_rxrpc, transport) +
112 			sizeof(struct sockaddr_in6);
113 		break;
114 #endif
115 
116 	default:
117 		return -EAFNOSUPPORT;
118 	}
119 
120 	if (tail < len)
121 		memset((void *)srx + tail, 0, len - tail);
122 	_debug("INET: %pISp", &srx->transport);
123 	return 0;
124 }
125 
126 /*
127  * bind a local address to an RxRPC socket
128  */
129 static int rxrpc_bind(struct socket *sock, struct sockaddr *saddr, int len)
130 {
131 	struct sockaddr_rxrpc *srx = (struct sockaddr_rxrpc *)saddr;
132 	struct rxrpc_local *local;
133 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
134 	u16 service_id;
135 	int ret;
136 
137 	_enter("%p,%p,%d", rx, saddr, len);
138 
139 	ret = rxrpc_validate_address(rx, srx, len);
140 	if (ret < 0)
141 		goto error;
142 	service_id = srx->srx_service;
143 
144 	lock_sock(&rx->sk);
145 
146 	switch (rx->sk.sk_state) {
147 	case RXRPC_UNBOUND:
148 		rx->srx = *srx;
149 		local = rxrpc_lookup_local(sock_net(&rx->sk), &rx->srx);
150 		if (IS_ERR(local)) {
151 			ret = PTR_ERR(local);
152 			goto error_unlock;
153 		}
154 
155 		if (service_id) {
156 			write_lock(&local->services_lock);
157 			if (rcu_access_pointer(local->service))
158 				goto service_in_use;
159 			rx->local = local;
160 			rcu_assign_pointer(local->service, rx);
161 			write_unlock(&local->services_lock);
162 
163 			rx->sk.sk_state = RXRPC_SERVER_BOUND;
164 		} else {
165 			rx->local = local;
166 			rx->sk.sk_state = RXRPC_CLIENT_BOUND;
167 		}
168 		break;
169 
170 	case RXRPC_SERVER_BOUND:
171 		ret = -EINVAL;
172 		if (service_id == 0)
173 			goto error_unlock;
174 		ret = -EADDRINUSE;
175 		if (service_id == rx->srx.srx_service)
176 			goto error_unlock;
177 		ret = -EINVAL;
178 		srx->srx_service = rx->srx.srx_service;
179 		if (memcmp(srx, &rx->srx, sizeof(*srx)) != 0)
180 			goto error_unlock;
181 		rx->second_service = service_id;
182 		rx->sk.sk_state = RXRPC_SERVER_BOUND2;
183 		break;
184 
185 	default:
186 		ret = -EINVAL;
187 		goto error_unlock;
188 	}
189 
190 	release_sock(&rx->sk);
191 	_leave(" = 0");
192 	return 0;
193 
194 service_in_use:
195 	write_unlock(&local->services_lock);
196 	rxrpc_unuse_local(local);
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 		fallthrough;
250 	default:
251 		ret = -EBUSY;
252 		break;
253 	}
254 
255 	release_sock(&rx->sk);
256 	_leave(" = %d", ret);
257 	return ret;
258 }
259 
260 /**
261  * rxrpc_kernel_begin_call - Allow a kernel service to begin a call
262  * @sock: The socket on which to make the call
263  * @srx: The address of the peer to contact
264  * @key: The security context to use (defaults to socket setting)
265  * @user_call_ID: The ID to use
266  * @tx_total_len: Total length of data to transmit during the call (or -1)
267  * @gfp: The allocation constraints
268  * @notify_rx: Where to send notifications instead of socket queue
269  * @upgrade: Request service upgrade for call
270  * @interruptibility: The call is interruptible, or can be canceled.
271  * @debug_id: The debug ID for tracing to be assigned to the call
272  *
273  * Allow a kernel service to begin a call on the nominated socket.  This just
274  * sets up all the internal tracking structures and allocates connection and
275  * call IDs as appropriate.  The call to be used is returned.
276  *
277  * The default socket destination address and security may be overridden by
278  * supplying @srx and @key.
279  */
280 struct rxrpc_call *rxrpc_kernel_begin_call(struct socket *sock,
281 					   struct sockaddr_rxrpc *srx,
282 					   struct key *key,
283 					   unsigned long user_call_ID,
284 					   s64 tx_total_len,
285 					   gfp_t gfp,
286 					   rxrpc_notify_rx_t notify_rx,
287 					   bool upgrade,
288 					   enum rxrpc_interruptibility interruptibility,
289 					   unsigned int debug_id)
290 {
291 	struct rxrpc_conn_parameters cp;
292 	struct rxrpc_call_params p;
293 	struct rxrpc_call *call;
294 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
295 	int ret;
296 
297 	_enter(",,%x,%lx", key_serial(key), user_call_ID);
298 
299 	ret = rxrpc_validate_address(rx, srx, sizeof(*srx));
300 	if (ret < 0)
301 		return ERR_PTR(ret);
302 
303 	lock_sock(&rx->sk);
304 
305 	if (!key)
306 		key = rx->key;
307 	if (key && !key->payload.data[0])
308 		key = NULL; /* a no-security key */
309 
310 	memset(&p, 0, sizeof(p));
311 	p.user_call_ID		= user_call_ID;
312 	p.tx_total_len		= tx_total_len;
313 	p.interruptibility	= interruptibility;
314 	p.kernel		= true;
315 
316 	memset(&cp, 0, sizeof(cp));
317 	cp.local		= rx->local;
318 	cp.key			= key;
319 	cp.security_level	= rx->min_sec_level;
320 	cp.exclusive		= false;
321 	cp.upgrade		= upgrade;
322 	cp.service_id		= srx->srx_service;
323 	call = rxrpc_new_client_call(rx, &cp, srx, &p, gfp, debug_id);
324 	/* The socket has been unlocked. */
325 	if (!IS_ERR(call)) {
326 		call->notify_rx = notify_rx;
327 		mutex_unlock(&call->user_mutex);
328 	}
329 
330 	rxrpc_put_peer(cp.peer);
331 	_leave(" = %p", call);
332 	return call;
333 }
334 EXPORT_SYMBOL(rxrpc_kernel_begin_call);
335 
336 /*
337  * Dummy function used to stop the notifier talking to recvmsg().
338  */
339 static void rxrpc_dummy_notify_rx(struct sock *sk, struct rxrpc_call *rxcall,
340 				  unsigned long call_user_ID)
341 {
342 }
343 
344 /**
345  * rxrpc_kernel_end_call - Allow a kernel service to end a call it was using
346  * @sock: The socket the call is on
347  * @call: The call to end
348  *
349  * Allow a kernel service to end a call it was using.  The call must be
350  * complete before this is called (the call should be aborted if necessary).
351  */
352 void rxrpc_kernel_end_call(struct socket *sock, struct rxrpc_call *call)
353 {
354 	_enter("%d{%d}", call->debug_id, atomic_read(&call->usage));
355 
356 	mutex_lock(&call->user_mutex);
357 	rxrpc_release_call(rxrpc_sk(sock->sk), call);
358 
359 	/* Make sure we're not going to call back into a kernel service */
360 	if (call->notify_rx) {
361 		spin_lock_bh(&call->notify_lock);
362 		call->notify_rx = rxrpc_dummy_notify_rx;
363 		spin_unlock_bh(&call->notify_lock);
364 	}
365 
366 	mutex_unlock(&call->user_mutex);
367 	rxrpc_put_call(call, rxrpc_call_put_kernel);
368 }
369 EXPORT_SYMBOL(rxrpc_kernel_end_call);
370 
371 /**
372  * rxrpc_kernel_check_life - Check to see whether a call is still alive
373  * @sock: The socket the call is on
374  * @call: The call to check
375  *
376  * Allow a kernel service to find out whether a call is still alive -
377  * ie. whether it has completed.
378  */
379 bool rxrpc_kernel_check_life(const struct socket *sock,
380 			     const struct rxrpc_call *call)
381 {
382 	return call->state != RXRPC_CALL_COMPLETE;
383 }
384 EXPORT_SYMBOL(rxrpc_kernel_check_life);
385 
386 /**
387  * rxrpc_kernel_get_epoch - Retrieve the epoch value from a call.
388  * @sock: The socket the call is on
389  * @call: The call to query
390  *
391  * Allow a kernel service to retrieve the epoch value from a service call to
392  * see if the client at the other end rebooted.
393  */
394 u32 rxrpc_kernel_get_epoch(struct socket *sock, struct rxrpc_call *call)
395 {
396 	return call->conn->proto.epoch;
397 }
398 EXPORT_SYMBOL(rxrpc_kernel_get_epoch);
399 
400 /**
401  * rxrpc_kernel_new_call_notification - Get notifications of new calls
402  * @sock: The socket to intercept received messages on
403  * @notify_new_call: Function to be called when new calls appear
404  * @discard_new_call: Function to discard preallocated calls
405  *
406  * Allow a kernel service to be given notifications about new calls.
407  */
408 void rxrpc_kernel_new_call_notification(
409 	struct socket *sock,
410 	rxrpc_notify_new_call_t notify_new_call,
411 	rxrpc_discard_new_call_t discard_new_call)
412 {
413 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
414 
415 	rx->notify_new_call = notify_new_call;
416 	rx->discard_new_call = discard_new_call;
417 }
418 EXPORT_SYMBOL(rxrpc_kernel_new_call_notification);
419 
420 /**
421  * rxrpc_kernel_set_max_life - Set maximum lifespan on a call
422  * @sock: The socket the call is on
423  * @call: The call to configure
424  * @hard_timeout: The maximum lifespan of the call in jiffies
425  *
426  * Set the maximum lifespan of a call.  The call will end with ETIME or
427  * ETIMEDOUT if it takes longer than this.
428  */
429 void rxrpc_kernel_set_max_life(struct socket *sock, struct rxrpc_call *call,
430 			       unsigned long hard_timeout)
431 {
432 	unsigned long now;
433 
434 	mutex_lock(&call->user_mutex);
435 
436 	now = jiffies;
437 	hard_timeout += now;
438 	WRITE_ONCE(call->expect_term_by, hard_timeout);
439 	rxrpc_reduce_call_timer(call, hard_timeout, now, rxrpc_timer_set_for_hard);
440 
441 	mutex_unlock(&call->user_mutex);
442 }
443 EXPORT_SYMBOL(rxrpc_kernel_set_max_life);
444 
445 /*
446  * connect an RxRPC socket
447  * - this just targets it at a specific destination; no actual connection
448  *   negotiation takes place
449  */
450 static int rxrpc_connect(struct socket *sock, struct sockaddr *addr,
451 			 int addr_len, int flags)
452 {
453 	struct sockaddr_rxrpc *srx = (struct sockaddr_rxrpc *)addr;
454 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
455 	int ret;
456 
457 	_enter("%p,%p,%d,%d", rx, addr, addr_len, flags);
458 
459 	ret = rxrpc_validate_address(rx, srx, addr_len);
460 	if (ret < 0) {
461 		_leave(" = %d [bad addr]", ret);
462 		return ret;
463 	}
464 
465 	lock_sock(&rx->sk);
466 
467 	ret = -EISCONN;
468 	if (test_bit(RXRPC_SOCK_CONNECTED, &rx->flags))
469 		goto error;
470 
471 	switch (rx->sk.sk_state) {
472 	case RXRPC_UNBOUND:
473 		rx->sk.sk_state = RXRPC_CLIENT_UNBOUND;
474 	case RXRPC_CLIENT_UNBOUND:
475 	case RXRPC_CLIENT_BOUND:
476 		break;
477 	default:
478 		ret = -EBUSY;
479 		goto error;
480 	}
481 
482 	rx->connect_srx = *srx;
483 	set_bit(RXRPC_SOCK_CONNECTED, &rx->flags);
484 	ret = 0;
485 
486 error:
487 	release_sock(&rx->sk);
488 	return ret;
489 }
490 
491 /*
492  * send a message through an RxRPC socket
493  * - in a client this does a number of things:
494  *   - finds/sets up a connection for the security specified (if any)
495  *   - initiates a call (ID in control data)
496  *   - ends the request phase of a call (if MSG_MORE is not set)
497  *   - sends a call data packet
498  *   - may send an abort (abort code in control data)
499  */
500 static int rxrpc_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
501 {
502 	struct rxrpc_local *local;
503 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
504 	int ret;
505 
506 	_enter(",{%d},,%zu", rx->sk.sk_state, len);
507 
508 	if (m->msg_flags & MSG_OOB)
509 		return -EOPNOTSUPP;
510 
511 	if (m->msg_name) {
512 		ret = rxrpc_validate_address(rx, m->msg_name, m->msg_namelen);
513 		if (ret < 0) {
514 			_leave(" = %d [bad addr]", ret);
515 			return ret;
516 		}
517 	}
518 
519 	lock_sock(&rx->sk);
520 
521 	switch (rx->sk.sk_state) {
522 	case RXRPC_UNBOUND:
523 	case RXRPC_CLIENT_UNBOUND:
524 		rx->srx.srx_family = AF_RXRPC;
525 		rx->srx.srx_service = 0;
526 		rx->srx.transport_type = SOCK_DGRAM;
527 		rx->srx.transport.family = rx->family;
528 		switch (rx->family) {
529 		case AF_INET:
530 			rx->srx.transport_len = sizeof(struct sockaddr_in);
531 			break;
532 #ifdef CONFIG_AF_RXRPC_IPV6
533 		case AF_INET6:
534 			rx->srx.transport_len = sizeof(struct sockaddr_in6);
535 			break;
536 #endif
537 		default:
538 			ret = -EAFNOSUPPORT;
539 			goto error_unlock;
540 		}
541 		local = rxrpc_lookup_local(sock_net(sock->sk), &rx->srx);
542 		if (IS_ERR(local)) {
543 			ret = PTR_ERR(local);
544 			goto error_unlock;
545 		}
546 
547 		rx->local = local;
548 		rx->sk.sk_state = RXRPC_CLIENT_BOUND;
549 		fallthrough;
550 
551 	case RXRPC_CLIENT_BOUND:
552 		if (!m->msg_name &&
553 		    test_bit(RXRPC_SOCK_CONNECTED, &rx->flags)) {
554 			m->msg_name = &rx->connect_srx;
555 			m->msg_namelen = sizeof(rx->connect_srx);
556 		}
557 		fallthrough;
558 	case RXRPC_SERVER_BOUND:
559 	case RXRPC_SERVER_LISTENING:
560 		ret = rxrpc_do_sendmsg(rx, m, len);
561 		/* The socket has been unlocked */
562 		goto out;
563 	default:
564 		ret = -EINVAL;
565 		goto error_unlock;
566 	}
567 
568 error_unlock:
569 	release_sock(&rx->sk);
570 out:
571 	_leave(" = %d", ret);
572 	return ret;
573 }
574 
575 int rxrpc_sock_set_min_security_level(struct sock *sk, unsigned int val)
576 {
577 	if (sk->sk_state != RXRPC_UNBOUND)
578 		return -EISCONN;
579 	if (val > RXRPC_SECURITY_MAX)
580 		return -EINVAL;
581 	lock_sock(sk);
582 	rxrpc_sk(sk)->min_sec_level = val;
583 	release_sock(sk);
584 	return 0;
585 }
586 EXPORT_SYMBOL(rxrpc_sock_set_min_security_level);
587 
588 /*
589  * set RxRPC socket options
590  */
591 static int rxrpc_setsockopt(struct socket *sock, int level, int optname,
592 			    sockptr_t optval, unsigned int optlen)
593 {
594 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
595 	unsigned int min_sec_level;
596 	u16 service_upgrade[2];
597 	int ret;
598 
599 	_enter(",%d,%d,,%d", level, optname, optlen);
600 
601 	lock_sock(&rx->sk);
602 	ret = -EOPNOTSUPP;
603 
604 	if (level == SOL_RXRPC) {
605 		switch (optname) {
606 		case RXRPC_EXCLUSIVE_CONNECTION:
607 			ret = -EINVAL;
608 			if (optlen != 0)
609 				goto error;
610 			ret = -EISCONN;
611 			if (rx->sk.sk_state != RXRPC_UNBOUND)
612 				goto error;
613 			rx->exclusive = true;
614 			goto success;
615 
616 		case RXRPC_SECURITY_KEY:
617 			ret = -EINVAL;
618 			if (rx->key)
619 				goto error;
620 			ret = -EISCONN;
621 			if (rx->sk.sk_state != RXRPC_UNBOUND)
622 				goto error;
623 			ret = rxrpc_request_key(rx, optval, optlen);
624 			goto error;
625 
626 		case RXRPC_SECURITY_KEYRING:
627 			ret = -EINVAL;
628 			if (rx->key)
629 				goto error;
630 			ret = -EISCONN;
631 			if (rx->sk.sk_state != RXRPC_UNBOUND)
632 				goto error;
633 			ret = rxrpc_server_keyring(rx, optval, optlen);
634 			goto error;
635 
636 		case RXRPC_MIN_SECURITY_LEVEL:
637 			ret = -EINVAL;
638 			if (optlen != sizeof(unsigned int))
639 				goto error;
640 			ret = -EISCONN;
641 			if (rx->sk.sk_state != RXRPC_UNBOUND)
642 				goto error;
643 			ret = copy_from_sockptr(&min_sec_level, optval,
644 				       sizeof(unsigned int));
645 			if (ret < 0)
646 				goto error;
647 			ret = -EINVAL;
648 			if (min_sec_level > RXRPC_SECURITY_MAX)
649 				goto error;
650 			rx->min_sec_level = min_sec_level;
651 			goto success;
652 
653 		case RXRPC_UPGRADEABLE_SERVICE:
654 			ret = -EINVAL;
655 			if (optlen != sizeof(service_upgrade) ||
656 			    rx->service_upgrade.from != 0)
657 				goto error;
658 			ret = -EISCONN;
659 			if (rx->sk.sk_state != RXRPC_SERVER_BOUND2)
660 				goto error;
661 			ret = -EFAULT;
662 			if (copy_from_sockptr(service_upgrade, optval,
663 					   sizeof(service_upgrade)) != 0)
664 				goto error;
665 			ret = -EINVAL;
666 			if ((service_upgrade[0] != rx->srx.srx_service ||
667 			     service_upgrade[1] != rx->second_service) &&
668 			    (service_upgrade[0] != rx->second_service ||
669 			     service_upgrade[1] != rx->srx.srx_service))
670 				goto error;
671 			rx->service_upgrade.from = service_upgrade[0];
672 			rx->service_upgrade.to = service_upgrade[1];
673 			goto success;
674 
675 		default:
676 			break;
677 		}
678 	}
679 
680 success:
681 	ret = 0;
682 error:
683 	release_sock(&rx->sk);
684 	return ret;
685 }
686 
687 /*
688  * Get socket options.
689  */
690 static int rxrpc_getsockopt(struct socket *sock, int level, int optname,
691 			    char __user *optval, int __user *_optlen)
692 {
693 	int optlen;
694 
695 	if (level != SOL_RXRPC)
696 		return -EOPNOTSUPP;
697 
698 	if (get_user(optlen, _optlen))
699 		return -EFAULT;
700 
701 	switch (optname) {
702 	case RXRPC_SUPPORTED_CMSG:
703 		if (optlen < sizeof(int))
704 			return -ETOOSMALL;
705 		if (put_user(RXRPC__SUPPORTED - 1, (int __user *)optval) ||
706 		    put_user(sizeof(int), _optlen))
707 			return -EFAULT;
708 		return 0;
709 
710 	default:
711 		return -EOPNOTSUPP;
712 	}
713 }
714 
715 /*
716  * permit an RxRPC socket to be polled
717  */
718 static __poll_t rxrpc_poll(struct file *file, struct socket *sock,
719 			       poll_table *wait)
720 {
721 	struct sock *sk = sock->sk;
722 	struct rxrpc_sock *rx = rxrpc_sk(sk);
723 	__poll_t mask;
724 
725 	sock_poll_wait(file, sock, wait);
726 	mask = 0;
727 
728 	/* the socket is readable if there are any messages waiting on the Rx
729 	 * queue */
730 	if (!list_empty(&rx->recvmsg_q))
731 		mask |= EPOLLIN | EPOLLRDNORM;
732 
733 	/* the socket is writable if there is space to add new data to the
734 	 * socket; there is no guarantee that any particular call in progress
735 	 * on the socket may have space in the Tx ACK window */
736 	if (rxrpc_writable(sk))
737 		mask |= EPOLLOUT | EPOLLWRNORM;
738 
739 	return mask;
740 }
741 
742 /*
743  * create an RxRPC socket
744  */
745 static int rxrpc_create(struct net *net, struct socket *sock, int protocol,
746 			int kern)
747 {
748 	struct rxrpc_net *rxnet;
749 	struct rxrpc_sock *rx;
750 	struct sock *sk;
751 
752 	_enter("%p,%d", sock, protocol);
753 
754 	/* we support transport protocol UDP/UDP6 only */
755 	if (protocol != PF_INET &&
756 	    IS_ENABLED(CONFIG_AF_RXRPC_IPV6) && protocol != PF_INET6)
757 		return -EPROTONOSUPPORT;
758 
759 	if (sock->type != SOCK_DGRAM)
760 		return -ESOCKTNOSUPPORT;
761 
762 	sock->ops = &rxrpc_rpc_ops;
763 	sock->state = SS_UNCONNECTED;
764 
765 	sk = sk_alloc(net, PF_RXRPC, GFP_KERNEL, &rxrpc_proto, kern);
766 	if (!sk)
767 		return -ENOMEM;
768 
769 	sock_init_data(sock, sk);
770 	sock_set_flag(sk, SOCK_RCU_FREE);
771 	sk->sk_state		= RXRPC_UNBOUND;
772 	sk->sk_write_space	= rxrpc_write_space;
773 	sk->sk_max_ack_backlog	= 0;
774 	sk->sk_destruct		= rxrpc_sock_destructor;
775 
776 	rx = rxrpc_sk(sk);
777 	rx->family = protocol;
778 	rx->calls = RB_ROOT;
779 
780 	spin_lock_init(&rx->incoming_lock);
781 	INIT_LIST_HEAD(&rx->sock_calls);
782 	INIT_LIST_HEAD(&rx->to_be_accepted);
783 	INIT_LIST_HEAD(&rx->recvmsg_q);
784 	rwlock_init(&rx->recvmsg_lock);
785 	rwlock_init(&rx->call_lock);
786 	memset(&rx->srx, 0, sizeof(rx->srx));
787 
788 	rxnet = rxrpc_net(sock_net(&rx->sk));
789 	timer_reduce(&rxnet->peer_keepalive_timer, jiffies + 1);
790 
791 	_leave(" = 0 [%p]", rx);
792 	return 0;
793 }
794 
795 /*
796  * Kill all the calls on a socket and shut it down.
797  */
798 static int rxrpc_shutdown(struct socket *sock, int flags)
799 {
800 	struct sock *sk = sock->sk;
801 	struct rxrpc_sock *rx = rxrpc_sk(sk);
802 	int ret = 0;
803 
804 	_enter("%p,%d", sk, flags);
805 
806 	if (flags != SHUT_RDWR)
807 		return -EOPNOTSUPP;
808 	if (sk->sk_state == RXRPC_CLOSE)
809 		return -ESHUTDOWN;
810 
811 	lock_sock(sk);
812 
813 	spin_lock_bh(&sk->sk_receive_queue.lock);
814 	if (sk->sk_state < RXRPC_CLOSE) {
815 		sk->sk_state = RXRPC_CLOSE;
816 		sk->sk_shutdown = SHUTDOWN_MASK;
817 	} else {
818 		ret = -ESHUTDOWN;
819 	}
820 	spin_unlock_bh(&sk->sk_receive_queue.lock);
821 
822 	rxrpc_discard_prealloc(rx);
823 
824 	release_sock(sk);
825 	return ret;
826 }
827 
828 /*
829  * RxRPC socket destructor
830  */
831 static void rxrpc_sock_destructor(struct sock *sk)
832 {
833 	_enter("%p", sk);
834 
835 	rxrpc_purge_queue(&sk->sk_receive_queue);
836 
837 	WARN_ON(refcount_read(&sk->sk_wmem_alloc));
838 	WARN_ON(!sk_unhashed(sk));
839 	WARN_ON(sk->sk_socket);
840 
841 	if (!sock_flag(sk, SOCK_DEAD)) {
842 		printk("Attempt to release alive rxrpc socket: %p\n", sk);
843 		return;
844 	}
845 }
846 
847 /*
848  * release an RxRPC socket
849  */
850 static int rxrpc_release_sock(struct sock *sk)
851 {
852 	struct rxrpc_sock *rx = rxrpc_sk(sk);
853 
854 	_enter("%p{%d,%d}", sk, sk->sk_state, refcount_read(&sk->sk_refcnt));
855 
856 	/* declare the socket closed for business */
857 	sock_orphan(sk);
858 	sk->sk_shutdown = SHUTDOWN_MASK;
859 
860 	/* We want to kill off all connections from a service socket
861 	 * as fast as possible because we can't share these; client
862 	 * sockets, on the other hand, can share an endpoint.
863 	 */
864 	switch (sk->sk_state) {
865 	case RXRPC_SERVER_BOUND:
866 	case RXRPC_SERVER_BOUND2:
867 	case RXRPC_SERVER_LISTENING:
868 	case RXRPC_SERVER_LISTEN_DISABLED:
869 		rx->local->service_closed = true;
870 		break;
871 	}
872 
873 	spin_lock_bh(&sk->sk_receive_queue.lock);
874 	sk->sk_state = RXRPC_CLOSE;
875 	spin_unlock_bh(&sk->sk_receive_queue.lock);
876 
877 	if (rx->local && rcu_access_pointer(rx->local->service) == rx) {
878 		write_lock(&rx->local->services_lock);
879 		rcu_assign_pointer(rx->local->service, NULL);
880 		write_unlock(&rx->local->services_lock);
881 	}
882 
883 	/* try to flush out this socket */
884 	rxrpc_discard_prealloc(rx);
885 	rxrpc_release_calls_on_socket(rx);
886 	flush_workqueue(rxrpc_workqueue);
887 	rxrpc_purge_queue(&sk->sk_receive_queue);
888 
889 	rxrpc_unuse_local(rx->local);
890 	rxrpc_put_local(rx->local);
891 	rx->local = NULL;
892 	key_put(rx->key);
893 	rx->key = NULL;
894 	key_put(rx->securities);
895 	rx->securities = NULL;
896 	sock_put(sk);
897 
898 	_leave(" = 0");
899 	return 0;
900 }
901 
902 /*
903  * release an RxRPC BSD socket on close() or equivalent
904  */
905 static int rxrpc_release(struct socket *sock)
906 {
907 	struct sock *sk = sock->sk;
908 
909 	_enter("%p{%p}", sock, sk);
910 
911 	if (!sk)
912 		return 0;
913 
914 	sock->sk = NULL;
915 
916 	return rxrpc_release_sock(sk);
917 }
918 
919 /*
920  * RxRPC network protocol
921  */
922 static const struct proto_ops rxrpc_rpc_ops = {
923 	.family		= PF_RXRPC,
924 	.owner		= THIS_MODULE,
925 	.release	= rxrpc_release,
926 	.bind		= rxrpc_bind,
927 	.connect	= rxrpc_connect,
928 	.socketpair	= sock_no_socketpair,
929 	.accept		= sock_no_accept,
930 	.getname	= sock_no_getname,
931 	.poll		= rxrpc_poll,
932 	.ioctl		= sock_no_ioctl,
933 	.listen		= rxrpc_listen,
934 	.shutdown	= rxrpc_shutdown,
935 	.setsockopt	= rxrpc_setsockopt,
936 	.getsockopt	= rxrpc_getsockopt,
937 	.sendmsg	= rxrpc_sendmsg,
938 	.recvmsg	= rxrpc_recvmsg,
939 	.mmap		= sock_no_mmap,
940 	.sendpage	= sock_no_sendpage,
941 };
942 
943 static struct proto rxrpc_proto = {
944 	.name		= "RXRPC",
945 	.owner		= THIS_MODULE,
946 	.obj_size	= sizeof(struct rxrpc_sock),
947 	.max_header	= sizeof(struct rxrpc_wire_header),
948 };
949 
950 static const struct net_proto_family rxrpc_family_ops = {
951 	.family	= PF_RXRPC,
952 	.create = rxrpc_create,
953 	.owner	= THIS_MODULE,
954 };
955 
956 /*
957  * initialise and register the RxRPC protocol
958  */
959 static int __init af_rxrpc_init(void)
960 {
961 	int ret = -1;
962 	unsigned int tmp;
963 
964 	BUILD_BUG_ON(sizeof(struct rxrpc_skb_priv) > sizeof_field(struct sk_buff, cb));
965 
966 	get_random_bytes(&tmp, sizeof(tmp));
967 	tmp &= 0x3fffffff;
968 	if (tmp == 0)
969 		tmp = 1;
970 	idr_set_cursor(&rxrpc_client_conn_ids, tmp);
971 
972 	ret = -ENOMEM;
973 	rxrpc_call_jar = kmem_cache_create(
974 		"rxrpc_call_jar", sizeof(struct rxrpc_call), 0,
975 		SLAB_HWCACHE_ALIGN, NULL);
976 	if (!rxrpc_call_jar) {
977 		pr_notice("Failed to allocate call jar\n");
978 		goto error_call_jar;
979 	}
980 
981 	rxrpc_workqueue = alloc_workqueue("krxrpcd", 0, 1);
982 	if (!rxrpc_workqueue) {
983 		pr_notice("Failed to allocate work queue\n");
984 		goto error_work_queue;
985 	}
986 
987 	ret = rxrpc_init_security();
988 	if (ret < 0) {
989 		pr_crit("Cannot initialise security\n");
990 		goto error_security;
991 	}
992 
993 	ret = register_pernet_device(&rxrpc_net_ops);
994 	if (ret)
995 		goto error_pernet;
996 
997 	ret = proto_register(&rxrpc_proto, 1);
998 	if (ret < 0) {
999 		pr_crit("Cannot register protocol\n");
1000 		goto error_proto;
1001 	}
1002 
1003 	ret = sock_register(&rxrpc_family_ops);
1004 	if (ret < 0) {
1005 		pr_crit("Cannot register socket family\n");
1006 		goto error_sock;
1007 	}
1008 
1009 	ret = register_key_type(&key_type_rxrpc);
1010 	if (ret < 0) {
1011 		pr_crit("Cannot register client key type\n");
1012 		goto error_key_type;
1013 	}
1014 
1015 	ret = register_key_type(&key_type_rxrpc_s);
1016 	if (ret < 0) {
1017 		pr_crit("Cannot register server key type\n");
1018 		goto error_key_type_s;
1019 	}
1020 
1021 	ret = rxrpc_sysctl_init();
1022 	if (ret < 0) {
1023 		pr_crit("Cannot register sysctls\n");
1024 		goto error_sysctls;
1025 	}
1026 
1027 	return 0;
1028 
1029 error_sysctls:
1030 	unregister_key_type(&key_type_rxrpc_s);
1031 error_key_type_s:
1032 	unregister_key_type(&key_type_rxrpc);
1033 error_key_type:
1034 	sock_unregister(PF_RXRPC);
1035 error_sock:
1036 	proto_unregister(&rxrpc_proto);
1037 error_proto:
1038 	unregister_pernet_device(&rxrpc_net_ops);
1039 error_pernet:
1040 	rxrpc_exit_security();
1041 error_security:
1042 	destroy_workqueue(rxrpc_workqueue);
1043 error_work_queue:
1044 	kmem_cache_destroy(rxrpc_call_jar);
1045 error_call_jar:
1046 	return ret;
1047 }
1048 
1049 /*
1050  * unregister the RxRPC protocol
1051  */
1052 static void __exit af_rxrpc_exit(void)
1053 {
1054 	_enter("");
1055 	rxrpc_sysctl_exit();
1056 	unregister_key_type(&key_type_rxrpc_s);
1057 	unregister_key_type(&key_type_rxrpc);
1058 	sock_unregister(PF_RXRPC);
1059 	proto_unregister(&rxrpc_proto);
1060 	unregister_pernet_device(&rxrpc_net_ops);
1061 	ASSERTCMP(atomic_read(&rxrpc_n_tx_skbs), ==, 0);
1062 	ASSERTCMP(atomic_read(&rxrpc_n_rx_skbs), ==, 0);
1063 
1064 	/* Make sure the local and peer records pinned by any dying connections
1065 	 * are released.
1066 	 */
1067 	rcu_barrier();
1068 	rxrpc_destroy_client_conn_ids();
1069 
1070 	destroy_workqueue(rxrpc_workqueue);
1071 	rxrpc_exit_security();
1072 	kmem_cache_destroy(rxrpc_call_jar);
1073 	_leave("");
1074 }
1075 
1076 module_init(af_rxrpc_init);
1077 module_exit(af_rxrpc_exit);
1078