xref: /kernel/linux/linux-6.6/net/rxrpc/af_rxrpc.c (revision 62306a36)
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
25MODULE_DESCRIPTION("RxRPC network protocol");
26MODULE_AUTHOR("Red Hat, Inc.");
27MODULE_LICENSE("GPL");
28MODULE_ALIAS_NETPROTO(PF_RXRPC);
29
30unsigned int rxrpc_debug; // = RXRPC_DEBUG_KPROTO;
31module_param_named(debug, rxrpc_debug, uint, 0644);
32MODULE_PARM_DESC(debug, "RxRPC debugging mask");
33
34static struct proto rxrpc_proto;
35static const struct proto_ops rxrpc_rpc_ops;
36
37/* current debugging ID */
38atomic_t rxrpc_debug_id;
39EXPORT_SYMBOL(rxrpc_debug_id);
40
41/* count of skbs currently in use */
42atomic_t rxrpc_n_rx_skbs;
43
44struct workqueue_struct *rxrpc_workqueue;
45
46static void rxrpc_sock_destructor(struct sock *);
47
48/*
49 * see if an RxRPC socket is currently writable
50 */
51static 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 */
59static 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 */
76static 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	switch (srx->transport.family) {
97	case AF_INET:
98		if (rx->family != AF_INET &&
99		    rx->family != AF_INET6)
100			return -EAFNOSUPPORT;
101		if (srx->transport_len < sizeof(struct sockaddr_in))
102			return -EINVAL;
103		tail = offsetof(struct sockaddr_rxrpc, transport.sin.__pad);
104		break;
105
106#ifdef CONFIG_AF_RXRPC_IPV6
107	case AF_INET6:
108		if (rx->family != AF_INET6)
109			return -EAFNOSUPPORT;
110		if (srx->transport_len < sizeof(struct sockaddr_in6))
111			return -EINVAL;
112		tail = offsetof(struct sockaddr_rxrpc, transport) +
113			sizeof(struct sockaddr_in6);
114		break;
115#endif
116
117	default:
118		return -EAFNOSUPPORT;
119	}
120
121	if (tail < len)
122		memset((void *)srx + tail, 0, len - tail);
123	_debug("INET: %pISp", &srx->transport);
124	return 0;
125}
126
127/*
128 * bind a local address to an RxRPC socket
129 */
130static int rxrpc_bind(struct socket *sock, struct sockaddr *saddr, int len)
131{
132	struct sockaddr_rxrpc *srx = (struct sockaddr_rxrpc *)saddr;
133	struct rxrpc_local *local;
134	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
135	u16 service_id;
136	int ret;
137
138	_enter("%p,%p,%d", rx, saddr, len);
139
140	ret = rxrpc_validate_address(rx, srx, len);
141	if (ret < 0)
142		goto error;
143	service_id = srx->srx_service;
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 (local->service)
159				goto service_in_use;
160			rx->local = local;
161			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
195service_in_use:
196	write_unlock(&local->services_lock);
197	rxrpc_unuse_local(local, rxrpc_local_unuse_bind);
198	rxrpc_put_local(local, rxrpc_local_put_bind);
199	ret = -EADDRINUSE;
200error_unlock:
201	release_sock(&rx->sk);
202error:
203	_leave(" = %d", ret);
204	return ret;
205}
206
207/*
208 * set the number of pending calls permitted on a listening socket
209 */
210static int rxrpc_listen(struct socket *sock, int backlog)
211{
212	struct sock *sk = sock->sk;
213	struct rxrpc_sock *rx = rxrpc_sk(sk);
214	unsigned int max, old;
215	int ret;
216
217	_enter("%p,%d", rx, backlog);
218
219	lock_sock(&rx->sk);
220
221	switch (rx->sk.sk_state) {
222	case RXRPC_UNBOUND:
223		ret = -EADDRNOTAVAIL;
224		break;
225	case RXRPC_SERVER_BOUND:
226	case RXRPC_SERVER_BOUND2:
227		ASSERT(rx->local != NULL);
228		max = READ_ONCE(rxrpc_max_backlog);
229		ret = -EINVAL;
230		if (backlog == INT_MAX)
231			backlog = max;
232		else if (backlog < 0 || backlog > max)
233			break;
234		old = sk->sk_max_ack_backlog;
235		sk->sk_max_ack_backlog = backlog;
236		ret = rxrpc_service_prealloc(rx, GFP_KERNEL);
237		if (ret == 0)
238			rx->sk.sk_state = RXRPC_SERVER_LISTENING;
239		else
240			sk->sk_max_ack_backlog = old;
241		break;
242	case RXRPC_SERVER_LISTENING:
243		if (backlog == 0) {
244			rx->sk.sk_state = RXRPC_SERVER_LISTEN_DISABLED;
245			sk->sk_max_ack_backlog = 0;
246			rxrpc_discard_prealloc(rx);
247			ret = 0;
248			break;
249		}
250		fallthrough;
251	default:
252		ret = -EBUSY;
253		break;
254	}
255
256	release_sock(&rx->sk);
257	_leave(" = %d", ret);
258	return ret;
259}
260
261/**
262 * rxrpc_kernel_begin_call - Allow a kernel service to begin a call
263 * @sock: The socket on which to make the call
264 * @srx: The address of the peer to contact
265 * @key: The security context to use (defaults to socket setting)
266 * @user_call_ID: The ID to use
267 * @tx_total_len: Total length of data to transmit during the call (or -1)
268 * @hard_timeout: The maximum lifespan of the call in sec
269 * @gfp: The allocation constraints
270 * @notify_rx: Where to send notifications instead of socket queue
271 * @upgrade: Request service upgrade for call
272 * @interruptibility: The call is interruptible, or can be canceled.
273 * @debug_id: The debug ID for tracing to be assigned to the call
274 *
275 * Allow a kernel service to begin a call on the nominated socket.  This just
276 * sets up all the internal tracking structures and allocates connection and
277 * call IDs as appropriate.  The call to be used is returned.
278 *
279 * The default socket destination address and security may be overridden by
280 * supplying @srx and @key.
281 */
282struct rxrpc_call *rxrpc_kernel_begin_call(struct socket *sock,
283					   struct sockaddr_rxrpc *srx,
284					   struct key *key,
285					   unsigned long user_call_ID,
286					   s64 tx_total_len,
287					   u32 hard_timeout,
288					   gfp_t gfp,
289					   rxrpc_notify_rx_t notify_rx,
290					   bool upgrade,
291					   enum rxrpc_interruptibility interruptibility,
292					   unsigned int debug_id)
293{
294	struct rxrpc_conn_parameters cp;
295	struct rxrpc_call_params p;
296	struct rxrpc_call *call;
297	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
298	int ret;
299
300	_enter(",,%x,%lx", key_serial(key), user_call_ID);
301
302	ret = rxrpc_validate_address(rx, srx, sizeof(*srx));
303	if (ret < 0)
304		return ERR_PTR(ret);
305
306	lock_sock(&rx->sk);
307
308	if (!key)
309		key = rx->key;
310	if (key && !key->payload.data[0])
311		key = NULL; /* a no-security key */
312
313	memset(&p, 0, sizeof(p));
314	p.user_call_ID		= user_call_ID;
315	p.tx_total_len		= tx_total_len;
316	p.interruptibility	= interruptibility;
317	p.kernel		= true;
318	p.timeouts.hard		= hard_timeout;
319
320	memset(&cp, 0, sizeof(cp));
321	cp.local		= rx->local;
322	cp.key			= key;
323	cp.security_level	= rx->min_sec_level;
324	cp.exclusive		= false;
325	cp.upgrade		= upgrade;
326	cp.service_id		= srx->srx_service;
327	call = rxrpc_new_client_call(rx, &cp, srx, &p, gfp, debug_id);
328	/* The socket has been unlocked. */
329	if (!IS_ERR(call)) {
330		call->notify_rx = notify_rx;
331		mutex_unlock(&call->user_mutex);
332	}
333
334	_leave(" = %p", call);
335	return call;
336}
337EXPORT_SYMBOL(rxrpc_kernel_begin_call);
338
339/*
340 * Dummy function used to stop the notifier talking to recvmsg().
341 */
342static void rxrpc_dummy_notify_rx(struct sock *sk, struct rxrpc_call *rxcall,
343				  unsigned long call_user_ID)
344{
345}
346
347/**
348 * rxrpc_kernel_shutdown_call - Allow a kernel service to shut down a call it was using
349 * @sock: The socket the call is on
350 * @call: The call to end
351 *
352 * Allow a kernel service to shut down a call it was using.  The call must be
353 * complete before this is called (the call should be aborted if necessary).
354 */
355void rxrpc_kernel_shutdown_call(struct socket *sock, struct rxrpc_call *call)
356{
357	_enter("%d{%d}", call->debug_id, refcount_read(&call->ref));
358
359	mutex_lock(&call->user_mutex);
360	if (!test_bit(RXRPC_CALL_RELEASED, &call->flags)) {
361		rxrpc_release_call(rxrpc_sk(sock->sk), call);
362
363		/* Make sure we're not going to call back into a kernel service */
364		if (call->notify_rx) {
365			spin_lock(&call->notify_lock);
366			call->notify_rx = rxrpc_dummy_notify_rx;
367			spin_unlock(&call->notify_lock);
368		}
369	}
370	mutex_unlock(&call->user_mutex);
371}
372EXPORT_SYMBOL(rxrpc_kernel_shutdown_call);
373
374/**
375 * rxrpc_kernel_put_call - Release a reference to a call
376 * @sock: The socket the call is on
377 * @call: The call to put
378 *
379 * Drop the application's ref on an rxrpc call.
380 */
381void rxrpc_kernel_put_call(struct socket *sock, struct rxrpc_call *call)
382{
383	rxrpc_put_call(call, rxrpc_call_put_kernel);
384}
385EXPORT_SYMBOL(rxrpc_kernel_put_call);
386
387/**
388 * rxrpc_kernel_check_life - Check to see whether a call is still alive
389 * @sock: The socket the call is on
390 * @call: The call to check
391 *
392 * Allow a kernel service to find out whether a call is still alive - whether
393 * it has completed successfully and all received data has been consumed.
394 */
395bool rxrpc_kernel_check_life(const struct socket *sock,
396			     const struct rxrpc_call *call)
397{
398	if (!rxrpc_call_is_complete(call))
399		return true;
400	if (call->completion != RXRPC_CALL_SUCCEEDED)
401		return false;
402	return !skb_queue_empty(&call->recvmsg_queue);
403}
404EXPORT_SYMBOL(rxrpc_kernel_check_life);
405
406/**
407 * rxrpc_kernel_get_epoch - Retrieve the epoch value from a call.
408 * @sock: The socket the call is on
409 * @call: The call to query
410 *
411 * Allow a kernel service to retrieve the epoch value from a service call to
412 * see if the client at the other end rebooted.
413 */
414u32 rxrpc_kernel_get_epoch(struct socket *sock, struct rxrpc_call *call)
415{
416	return call->conn->proto.epoch;
417}
418EXPORT_SYMBOL(rxrpc_kernel_get_epoch);
419
420/**
421 * rxrpc_kernel_new_call_notification - Get notifications of new calls
422 * @sock: The socket to intercept received messages on
423 * @notify_new_call: Function to be called when new calls appear
424 * @discard_new_call: Function to discard preallocated calls
425 *
426 * Allow a kernel service to be given notifications about new calls.
427 */
428void rxrpc_kernel_new_call_notification(
429	struct socket *sock,
430	rxrpc_notify_new_call_t notify_new_call,
431	rxrpc_discard_new_call_t discard_new_call)
432{
433	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
434
435	rx->notify_new_call = notify_new_call;
436	rx->discard_new_call = discard_new_call;
437}
438EXPORT_SYMBOL(rxrpc_kernel_new_call_notification);
439
440/**
441 * rxrpc_kernel_set_max_life - Set maximum lifespan on a call
442 * @sock: The socket the call is on
443 * @call: The call to configure
444 * @hard_timeout: The maximum lifespan of the call in jiffies
445 *
446 * Set the maximum lifespan of a call.  The call will end with ETIME or
447 * ETIMEDOUT if it takes longer than this.
448 */
449void rxrpc_kernel_set_max_life(struct socket *sock, struct rxrpc_call *call,
450			       unsigned long hard_timeout)
451{
452	unsigned long now;
453
454	mutex_lock(&call->user_mutex);
455
456	now = jiffies;
457	hard_timeout += now;
458	WRITE_ONCE(call->expect_term_by, hard_timeout);
459	rxrpc_reduce_call_timer(call, hard_timeout, now, rxrpc_timer_set_for_hard);
460
461	mutex_unlock(&call->user_mutex);
462}
463EXPORT_SYMBOL(rxrpc_kernel_set_max_life);
464
465/*
466 * connect an RxRPC socket
467 * - this just targets it at a specific destination; no actual connection
468 *   negotiation takes place
469 */
470static int rxrpc_connect(struct socket *sock, struct sockaddr *addr,
471			 int addr_len, int flags)
472{
473	struct sockaddr_rxrpc *srx = (struct sockaddr_rxrpc *)addr;
474	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
475	int ret;
476
477	_enter("%p,%p,%d,%d", rx, addr, addr_len, flags);
478
479	ret = rxrpc_validate_address(rx, srx, addr_len);
480	if (ret < 0) {
481		_leave(" = %d [bad addr]", ret);
482		return ret;
483	}
484
485	lock_sock(&rx->sk);
486
487	ret = -EISCONN;
488	if (test_bit(RXRPC_SOCK_CONNECTED, &rx->flags))
489		goto error;
490
491	switch (rx->sk.sk_state) {
492	case RXRPC_UNBOUND:
493		rx->sk.sk_state = RXRPC_CLIENT_UNBOUND;
494		break;
495	case RXRPC_CLIENT_UNBOUND:
496	case RXRPC_CLIENT_BOUND:
497		break;
498	default:
499		ret = -EBUSY;
500		goto error;
501	}
502
503	rx->connect_srx = *srx;
504	set_bit(RXRPC_SOCK_CONNECTED, &rx->flags);
505	ret = 0;
506
507error:
508	release_sock(&rx->sk);
509	return ret;
510}
511
512/*
513 * send a message through an RxRPC socket
514 * - in a client this does a number of things:
515 *   - finds/sets up a connection for the security specified (if any)
516 *   - initiates a call (ID in control data)
517 *   - ends the request phase of a call (if MSG_MORE is not set)
518 *   - sends a call data packet
519 *   - may send an abort (abort code in control data)
520 */
521static int rxrpc_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
522{
523	struct rxrpc_local *local;
524	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
525	int ret;
526
527	_enter(",{%d},,%zu", rx->sk.sk_state, len);
528
529	if (m->msg_flags & MSG_OOB)
530		return -EOPNOTSUPP;
531
532	if (m->msg_name) {
533		ret = rxrpc_validate_address(rx, m->msg_name, m->msg_namelen);
534		if (ret < 0) {
535			_leave(" = %d [bad addr]", ret);
536			return ret;
537		}
538	}
539
540	lock_sock(&rx->sk);
541
542	switch (rx->sk.sk_state) {
543	case RXRPC_UNBOUND:
544	case RXRPC_CLIENT_UNBOUND:
545		rx->srx.srx_family = AF_RXRPC;
546		rx->srx.srx_service = 0;
547		rx->srx.transport_type = SOCK_DGRAM;
548		rx->srx.transport.family = rx->family;
549		switch (rx->family) {
550		case AF_INET:
551			rx->srx.transport_len = sizeof(struct sockaddr_in);
552			break;
553#ifdef CONFIG_AF_RXRPC_IPV6
554		case AF_INET6:
555			rx->srx.transport_len = sizeof(struct sockaddr_in6);
556			break;
557#endif
558		default:
559			ret = -EAFNOSUPPORT;
560			goto error_unlock;
561		}
562		local = rxrpc_lookup_local(sock_net(sock->sk), &rx->srx);
563		if (IS_ERR(local)) {
564			ret = PTR_ERR(local);
565			goto error_unlock;
566		}
567
568		rx->local = local;
569		rx->sk.sk_state = RXRPC_CLIENT_BOUND;
570		fallthrough;
571
572	case RXRPC_CLIENT_BOUND:
573		if (!m->msg_name &&
574		    test_bit(RXRPC_SOCK_CONNECTED, &rx->flags)) {
575			m->msg_name = &rx->connect_srx;
576			m->msg_namelen = sizeof(rx->connect_srx);
577		}
578		fallthrough;
579	case RXRPC_SERVER_BOUND:
580	case RXRPC_SERVER_LISTENING:
581		ret = rxrpc_do_sendmsg(rx, m, len);
582		/* The socket has been unlocked */
583		goto out;
584	default:
585		ret = -EINVAL;
586		goto error_unlock;
587	}
588
589error_unlock:
590	release_sock(&rx->sk);
591out:
592	_leave(" = %d", ret);
593	return ret;
594}
595
596int rxrpc_sock_set_min_security_level(struct sock *sk, unsigned int val)
597{
598	if (sk->sk_state != RXRPC_UNBOUND)
599		return -EISCONN;
600	if (val > RXRPC_SECURITY_MAX)
601		return -EINVAL;
602	lock_sock(sk);
603	rxrpc_sk(sk)->min_sec_level = val;
604	release_sock(sk);
605	return 0;
606}
607EXPORT_SYMBOL(rxrpc_sock_set_min_security_level);
608
609/*
610 * set RxRPC socket options
611 */
612static int rxrpc_setsockopt(struct socket *sock, int level, int optname,
613			    sockptr_t optval, unsigned int optlen)
614{
615	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
616	unsigned int min_sec_level;
617	u16 service_upgrade[2];
618	int ret;
619
620	_enter(",%d,%d,,%d", level, optname, optlen);
621
622	lock_sock(&rx->sk);
623	ret = -EOPNOTSUPP;
624
625	if (level == SOL_RXRPC) {
626		switch (optname) {
627		case RXRPC_EXCLUSIVE_CONNECTION:
628			ret = -EINVAL;
629			if (optlen != 0)
630				goto error;
631			ret = -EISCONN;
632			if (rx->sk.sk_state != RXRPC_UNBOUND)
633				goto error;
634			rx->exclusive = true;
635			goto success;
636
637		case RXRPC_SECURITY_KEY:
638			ret = -EINVAL;
639			if (rx->key)
640				goto error;
641			ret = -EISCONN;
642			if (rx->sk.sk_state != RXRPC_UNBOUND)
643				goto error;
644			ret = rxrpc_request_key(rx, optval, optlen);
645			goto error;
646
647		case RXRPC_SECURITY_KEYRING:
648			ret = -EINVAL;
649			if (rx->key)
650				goto error;
651			ret = -EISCONN;
652			if (rx->sk.sk_state != RXRPC_UNBOUND)
653				goto error;
654			ret = rxrpc_server_keyring(rx, optval, optlen);
655			goto error;
656
657		case RXRPC_MIN_SECURITY_LEVEL:
658			ret = -EINVAL;
659			if (optlen != sizeof(unsigned int))
660				goto error;
661			ret = -EISCONN;
662			if (rx->sk.sk_state != RXRPC_UNBOUND)
663				goto error;
664			ret = copy_from_sockptr(&min_sec_level, optval,
665				       sizeof(unsigned int));
666			if (ret < 0)
667				goto error;
668			ret = -EINVAL;
669			if (min_sec_level > RXRPC_SECURITY_MAX)
670				goto error;
671			rx->min_sec_level = min_sec_level;
672			goto success;
673
674		case RXRPC_UPGRADEABLE_SERVICE:
675			ret = -EINVAL;
676			if (optlen != sizeof(service_upgrade) ||
677			    rx->service_upgrade.from != 0)
678				goto error;
679			ret = -EISCONN;
680			if (rx->sk.sk_state != RXRPC_SERVER_BOUND2)
681				goto error;
682			ret = -EFAULT;
683			if (copy_from_sockptr(service_upgrade, optval,
684					   sizeof(service_upgrade)) != 0)
685				goto error;
686			ret = -EINVAL;
687			if ((service_upgrade[0] != rx->srx.srx_service ||
688			     service_upgrade[1] != rx->second_service) &&
689			    (service_upgrade[0] != rx->second_service ||
690			     service_upgrade[1] != rx->srx.srx_service))
691				goto error;
692			rx->service_upgrade.from = service_upgrade[0];
693			rx->service_upgrade.to = service_upgrade[1];
694			goto success;
695
696		default:
697			break;
698		}
699	}
700
701success:
702	ret = 0;
703error:
704	release_sock(&rx->sk);
705	return ret;
706}
707
708/*
709 * Get socket options.
710 */
711static int rxrpc_getsockopt(struct socket *sock, int level, int optname,
712			    char __user *optval, int __user *_optlen)
713{
714	int optlen;
715
716	if (level != SOL_RXRPC)
717		return -EOPNOTSUPP;
718
719	if (get_user(optlen, _optlen))
720		return -EFAULT;
721
722	switch (optname) {
723	case RXRPC_SUPPORTED_CMSG:
724		if (optlen < sizeof(int))
725			return -ETOOSMALL;
726		if (put_user(RXRPC__SUPPORTED - 1, (int __user *)optval) ||
727		    put_user(sizeof(int), _optlen))
728			return -EFAULT;
729		return 0;
730
731	default:
732		return -EOPNOTSUPP;
733	}
734}
735
736/*
737 * permit an RxRPC socket to be polled
738 */
739static __poll_t rxrpc_poll(struct file *file, struct socket *sock,
740			       poll_table *wait)
741{
742	struct sock *sk = sock->sk;
743	struct rxrpc_sock *rx = rxrpc_sk(sk);
744	__poll_t mask;
745
746	sock_poll_wait(file, sock, wait);
747	mask = 0;
748
749	/* the socket is readable if there are any messages waiting on the Rx
750	 * queue */
751	if (!list_empty(&rx->recvmsg_q))
752		mask |= EPOLLIN | EPOLLRDNORM;
753
754	/* the socket is writable if there is space to add new data to the
755	 * socket; there is no guarantee that any particular call in progress
756	 * on the socket may have space in the Tx ACK window */
757	if (rxrpc_writable(sk))
758		mask |= EPOLLOUT | EPOLLWRNORM;
759
760	return mask;
761}
762
763/*
764 * create an RxRPC socket
765 */
766static int rxrpc_create(struct net *net, struct socket *sock, int protocol,
767			int kern)
768{
769	struct rxrpc_net *rxnet;
770	struct rxrpc_sock *rx;
771	struct sock *sk;
772
773	_enter("%p,%d", sock, protocol);
774
775	/* we support transport protocol UDP/UDP6 only */
776	if (protocol != PF_INET &&
777	    IS_ENABLED(CONFIG_AF_RXRPC_IPV6) && protocol != PF_INET6)
778		return -EPROTONOSUPPORT;
779
780	if (sock->type != SOCK_DGRAM)
781		return -ESOCKTNOSUPPORT;
782
783	sock->ops = &rxrpc_rpc_ops;
784	sock->state = SS_UNCONNECTED;
785
786	sk = sk_alloc(net, PF_RXRPC, GFP_KERNEL, &rxrpc_proto, kern);
787	if (!sk)
788		return -ENOMEM;
789
790	sock_init_data(sock, sk);
791	sock_set_flag(sk, SOCK_RCU_FREE);
792	sk->sk_state		= RXRPC_UNBOUND;
793	sk->sk_write_space	= rxrpc_write_space;
794	sk->sk_max_ack_backlog	= 0;
795	sk->sk_destruct		= rxrpc_sock_destructor;
796
797	rx = rxrpc_sk(sk);
798	rx->family = protocol;
799	rx->calls = RB_ROOT;
800
801	spin_lock_init(&rx->incoming_lock);
802	INIT_LIST_HEAD(&rx->sock_calls);
803	INIT_LIST_HEAD(&rx->to_be_accepted);
804	INIT_LIST_HEAD(&rx->recvmsg_q);
805	spin_lock_init(&rx->recvmsg_lock);
806	rwlock_init(&rx->call_lock);
807	memset(&rx->srx, 0, sizeof(rx->srx));
808
809	rxnet = rxrpc_net(sock_net(&rx->sk));
810	timer_reduce(&rxnet->peer_keepalive_timer, jiffies + 1);
811
812	_leave(" = 0 [%p]", rx);
813	return 0;
814}
815
816/*
817 * Kill all the calls on a socket and shut it down.
818 */
819static int rxrpc_shutdown(struct socket *sock, int flags)
820{
821	struct sock *sk = sock->sk;
822	struct rxrpc_sock *rx = rxrpc_sk(sk);
823	int ret = 0;
824
825	_enter("%p,%d", sk, flags);
826
827	if (flags != SHUT_RDWR)
828		return -EOPNOTSUPP;
829	if (sk->sk_state == RXRPC_CLOSE)
830		return -ESHUTDOWN;
831
832	lock_sock(sk);
833
834	if (sk->sk_state < RXRPC_CLOSE) {
835		sk->sk_state = RXRPC_CLOSE;
836		sk->sk_shutdown = SHUTDOWN_MASK;
837	} else {
838		ret = -ESHUTDOWN;
839	}
840
841	rxrpc_discard_prealloc(rx);
842
843	release_sock(sk);
844	return ret;
845}
846
847/*
848 * RxRPC socket destructor
849 */
850static void rxrpc_sock_destructor(struct sock *sk)
851{
852	_enter("%p", sk);
853
854	rxrpc_purge_queue(&sk->sk_receive_queue);
855
856	WARN_ON(refcount_read(&sk->sk_wmem_alloc));
857	WARN_ON(!sk_unhashed(sk));
858	WARN_ON(sk->sk_socket);
859
860	if (!sock_flag(sk, SOCK_DEAD)) {
861		printk("Attempt to release alive rxrpc socket: %p\n", sk);
862		return;
863	}
864}
865
866/*
867 * release an RxRPC socket
868 */
869static int rxrpc_release_sock(struct sock *sk)
870{
871	struct rxrpc_sock *rx = rxrpc_sk(sk);
872
873	_enter("%p{%d,%d}", sk, sk->sk_state, refcount_read(&sk->sk_refcnt));
874
875	/* declare the socket closed for business */
876	sock_orphan(sk);
877	sk->sk_shutdown = SHUTDOWN_MASK;
878
879	/* We want to kill off all connections from a service socket
880	 * as fast as possible because we can't share these; client
881	 * sockets, on the other hand, can share an endpoint.
882	 */
883	switch (sk->sk_state) {
884	case RXRPC_SERVER_BOUND:
885	case RXRPC_SERVER_BOUND2:
886	case RXRPC_SERVER_LISTENING:
887	case RXRPC_SERVER_LISTEN_DISABLED:
888		rx->local->service_closed = true;
889		break;
890	}
891
892	sk->sk_state = RXRPC_CLOSE;
893
894	if (rx->local && rx->local->service == rx) {
895		write_lock(&rx->local->services_lock);
896		rx->local->service = NULL;
897		write_unlock(&rx->local->services_lock);
898	}
899
900	/* try to flush out this socket */
901	rxrpc_discard_prealloc(rx);
902	rxrpc_release_calls_on_socket(rx);
903	flush_workqueue(rxrpc_workqueue);
904	rxrpc_purge_queue(&sk->sk_receive_queue);
905
906	rxrpc_unuse_local(rx->local, rxrpc_local_unuse_release_sock);
907	rxrpc_put_local(rx->local, rxrpc_local_put_release_sock);
908	rx->local = NULL;
909	key_put(rx->key);
910	rx->key = NULL;
911	key_put(rx->securities);
912	rx->securities = NULL;
913	sock_put(sk);
914
915	_leave(" = 0");
916	return 0;
917}
918
919/*
920 * release an RxRPC BSD socket on close() or equivalent
921 */
922static int rxrpc_release(struct socket *sock)
923{
924	struct sock *sk = sock->sk;
925
926	_enter("%p{%p}", sock, sk);
927
928	if (!sk)
929		return 0;
930
931	sock->sk = NULL;
932
933	return rxrpc_release_sock(sk);
934}
935
936/*
937 * RxRPC network protocol
938 */
939static const struct proto_ops rxrpc_rpc_ops = {
940	.family		= PF_RXRPC,
941	.owner		= THIS_MODULE,
942	.release	= rxrpc_release,
943	.bind		= rxrpc_bind,
944	.connect	= rxrpc_connect,
945	.socketpair	= sock_no_socketpair,
946	.accept		= sock_no_accept,
947	.getname	= sock_no_getname,
948	.poll		= rxrpc_poll,
949	.ioctl		= sock_no_ioctl,
950	.listen		= rxrpc_listen,
951	.shutdown	= rxrpc_shutdown,
952	.setsockopt	= rxrpc_setsockopt,
953	.getsockopt	= rxrpc_getsockopt,
954	.sendmsg	= rxrpc_sendmsg,
955	.recvmsg	= rxrpc_recvmsg,
956	.mmap		= sock_no_mmap,
957};
958
959static struct proto rxrpc_proto = {
960	.name		= "RXRPC",
961	.owner		= THIS_MODULE,
962	.obj_size	= sizeof(struct rxrpc_sock),
963	.max_header	= sizeof(struct rxrpc_wire_header),
964};
965
966static const struct net_proto_family rxrpc_family_ops = {
967	.family	= PF_RXRPC,
968	.create = rxrpc_create,
969	.owner	= THIS_MODULE,
970};
971
972/*
973 * initialise and register the RxRPC protocol
974 */
975static int __init af_rxrpc_init(void)
976{
977	int ret = -1;
978
979	BUILD_BUG_ON(sizeof(struct rxrpc_skb_priv) > sizeof_field(struct sk_buff, cb));
980
981	ret = -ENOMEM;
982	rxrpc_gen_version_string();
983	rxrpc_call_jar = kmem_cache_create(
984		"rxrpc_call_jar", sizeof(struct rxrpc_call), 0,
985		SLAB_HWCACHE_ALIGN, NULL);
986	if (!rxrpc_call_jar) {
987		pr_notice("Failed to allocate call jar\n");
988		goto error_call_jar;
989	}
990
991	rxrpc_workqueue = alloc_ordered_workqueue("krxrpcd", WQ_HIGHPRI | WQ_MEM_RECLAIM);
992	if (!rxrpc_workqueue) {
993		pr_notice("Failed to allocate work queue\n");
994		goto error_work_queue;
995	}
996
997	ret = rxrpc_init_security();
998	if (ret < 0) {
999		pr_crit("Cannot initialise security\n");
1000		goto error_security;
1001	}
1002
1003	ret = register_pernet_device(&rxrpc_net_ops);
1004	if (ret)
1005		goto error_pernet;
1006
1007	ret = proto_register(&rxrpc_proto, 1);
1008	if (ret < 0) {
1009		pr_crit("Cannot register protocol\n");
1010		goto error_proto;
1011	}
1012
1013	ret = sock_register(&rxrpc_family_ops);
1014	if (ret < 0) {
1015		pr_crit("Cannot register socket family\n");
1016		goto error_sock;
1017	}
1018
1019	ret = register_key_type(&key_type_rxrpc);
1020	if (ret < 0) {
1021		pr_crit("Cannot register client key type\n");
1022		goto error_key_type;
1023	}
1024
1025	ret = register_key_type(&key_type_rxrpc_s);
1026	if (ret < 0) {
1027		pr_crit("Cannot register server key type\n");
1028		goto error_key_type_s;
1029	}
1030
1031	ret = rxrpc_sysctl_init();
1032	if (ret < 0) {
1033		pr_crit("Cannot register sysctls\n");
1034		goto error_sysctls;
1035	}
1036
1037	return 0;
1038
1039error_sysctls:
1040	unregister_key_type(&key_type_rxrpc_s);
1041error_key_type_s:
1042	unregister_key_type(&key_type_rxrpc);
1043error_key_type:
1044	sock_unregister(PF_RXRPC);
1045error_sock:
1046	proto_unregister(&rxrpc_proto);
1047error_proto:
1048	unregister_pernet_device(&rxrpc_net_ops);
1049error_pernet:
1050	rxrpc_exit_security();
1051error_security:
1052	destroy_workqueue(rxrpc_workqueue);
1053error_work_queue:
1054	kmem_cache_destroy(rxrpc_call_jar);
1055error_call_jar:
1056	return ret;
1057}
1058
1059/*
1060 * unregister the RxRPC protocol
1061 */
1062static void __exit af_rxrpc_exit(void)
1063{
1064	_enter("");
1065	rxrpc_sysctl_exit();
1066	unregister_key_type(&key_type_rxrpc_s);
1067	unregister_key_type(&key_type_rxrpc);
1068	sock_unregister(PF_RXRPC);
1069	proto_unregister(&rxrpc_proto);
1070	unregister_pernet_device(&rxrpc_net_ops);
1071	ASSERTCMP(atomic_read(&rxrpc_n_rx_skbs), ==, 0);
1072
1073	/* Make sure the local and peer records pinned by any dying connections
1074	 * are released.
1075	 */
1076	rcu_barrier();
1077
1078	destroy_workqueue(rxrpc_workqueue);
1079	rxrpc_exit_security();
1080	kmem_cache_destroy(rxrpc_call_jar);
1081	_leave("");
1082}
1083
1084module_init(af_rxrpc_init);
1085module_exit(af_rxrpc_exit);
1086