xref: /linux/net/rxrpc/af_rxrpc.c (revision 65ae975e97d5aab3ee9dc5ec701b12090572ed43)
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_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  */
rxrpc_writable(struct sock * sk)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  */
rxrpc_write_space(struct sock * sk)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_rcu(sk, SOCK_WAKE_SPACE, POLL_OUT);
69 	}
70 	rcu_read_unlock();
71 }
72 
73 /*
74  * validate an RxRPC address
75  */
rxrpc_validate_address(struct rxrpc_sock * rx,struct sockaddr_rxrpc * srx,int len)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 	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  */
rxrpc_bind(struct socket * sock,struct sockaddr * saddr,int len)130 static 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 
195 service_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;
200 error_unlock:
201 	release_sock(&rx->sk);
202 error:
203 	_leave(" = %d", ret);
204 	return ret;
205 }
206 
207 /*
208  * set the number of pending calls permitted on a listening socket
209  */
rxrpc_listen(struct socket * sock,int backlog)210 static 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_lookup_peer - Obtain remote transport endpoint for an address
263  * @sock: The socket through which it will be accessed
264  * @srx: The network address
265  * @gfp: Allocation flags
266  *
267  * Lookup or create a remote transport endpoint record for the specified
268  * address and return it with a ref held.
269  */
rxrpc_kernel_lookup_peer(struct socket * sock,struct sockaddr_rxrpc * srx,gfp_t gfp)270 struct rxrpc_peer *rxrpc_kernel_lookup_peer(struct socket *sock,
271 					    struct sockaddr_rxrpc *srx, gfp_t gfp)
272 {
273 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
274 	int ret;
275 
276 	ret = rxrpc_validate_address(rx, srx, sizeof(*srx));
277 	if (ret < 0)
278 		return ERR_PTR(ret);
279 
280 	return rxrpc_lookup_peer(rx->local, srx, gfp);
281 }
282 EXPORT_SYMBOL(rxrpc_kernel_lookup_peer);
283 
284 /**
285  * rxrpc_kernel_get_peer - Get a reference on a peer
286  * @peer: The peer to get a reference on.
287  *
288  * Get a record for the remote peer in a call.
289  */
rxrpc_kernel_get_peer(struct rxrpc_peer * peer)290 struct rxrpc_peer *rxrpc_kernel_get_peer(struct rxrpc_peer *peer)
291 {
292 	return peer ? rxrpc_get_peer(peer, rxrpc_peer_get_application) : NULL;
293 }
294 EXPORT_SYMBOL(rxrpc_kernel_get_peer);
295 
296 /**
297  * rxrpc_kernel_put_peer - Allow a kernel app to drop a peer reference
298  * @peer: The peer to drop a ref on
299  */
rxrpc_kernel_put_peer(struct rxrpc_peer * peer)300 void rxrpc_kernel_put_peer(struct rxrpc_peer *peer)
301 {
302 	rxrpc_put_peer(peer, rxrpc_peer_put_application);
303 }
304 EXPORT_SYMBOL(rxrpc_kernel_put_peer);
305 
306 /**
307  * rxrpc_kernel_begin_call - Allow a kernel service to begin a call
308  * @sock: The socket on which to make the call
309  * @peer: The peer to contact
310  * @key: The security context to use (defaults to socket setting)
311  * @user_call_ID: The ID to use
312  * @tx_total_len: Total length of data to transmit during the call (or -1)
313  * @hard_timeout: The maximum lifespan of the call in sec
314  * @gfp: The allocation constraints
315  * @notify_rx: Where to send notifications instead of socket queue
316  * @service_id: The ID of the service to contact
317  * @upgrade: Request service upgrade for call
318  * @interruptibility: The call is interruptible, or can be canceled.
319  * @debug_id: The debug ID for tracing to be assigned to the call
320  *
321  * Allow a kernel service to begin a call on the nominated socket.  This just
322  * sets up all the internal tracking structures and allocates connection and
323  * call IDs as appropriate.  The call to be used is returned.
324  *
325  * The default socket destination address and security may be overridden by
326  * supplying @srx and @key.
327  */
rxrpc_kernel_begin_call(struct socket * sock,struct rxrpc_peer * peer,struct key * key,unsigned long user_call_ID,s64 tx_total_len,u32 hard_timeout,gfp_t gfp,rxrpc_notify_rx_t notify_rx,u16 service_id,bool upgrade,enum rxrpc_interruptibility interruptibility,unsigned int debug_id)328 struct rxrpc_call *rxrpc_kernel_begin_call(struct socket *sock,
329 					   struct rxrpc_peer *peer,
330 					   struct key *key,
331 					   unsigned long user_call_ID,
332 					   s64 tx_total_len,
333 					   u32 hard_timeout,
334 					   gfp_t gfp,
335 					   rxrpc_notify_rx_t notify_rx,
336 					   u16 service_id,
337 					   bool upgrade,
338 					   enum rxrpc_interruptibility interruptibility,
339 					   unsigned int debug_id)
340 {
341 	struct rxrpc_conn_parameters cp;
342 	struct rxrpc_call_params p;
343 	struct rxrpc_call *call;
344 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
345 
346 	_enter(",,%x,%lx", key_serial(key), user_call_ID);
347 
348 	if (WARN_ON_ONCE(peer->local != rx->local))
349 		return ERR_PTR(-EIO);
350 
351 	lock_sock(&rx->sk);
352 
353 	if (!key)
354 		key = rx->key;
355 	if (key && !key->payload.data[0])
356 		key = NULL; /* a no-security key */
357 
358 	memset(&p, 0, sizeof(p));
359 	p.user_call_ID		= user_call_ID;
360 	p.tx_total_len		= tx_total_len;
361 	p.interruptibility	= interruptibility;
362 	p.kernel		= true;
363 	p.timeouts.hard		= hard_timeout;
364 
365 	memset(&cp, 0, sizeof(cp));
366 	cp.local		= rx->local;
367 	cp.peer			= peer;
368 	cp.key			= key;
369 	cp.security_level	= rx->min_sec_level;
370 	cp.exclusive		= false;
371 	cp.upgrade		= upgrade;
372 	cp.service_id		= service_id;
373 	call = rxrpc_new_client_call(rx, &cp, &p, gfp, debug_id);
374 	/* The socket has been unlocked. */
375 	if (!IS_ERR(call)) {
376 		call->notify_rx = notify_rx;
377 		mutex_unlock(&call->user_mutex);
378 	}
379 
380 	_leave(" = %p", call);
381 	return call;
382 }
383 EXPORT_SYMBOL(rxrpc_kernel_begin_call);
384 
385 /*
386  * Dummy function used to stop the notifier talking to recvmsg().
387  */
rxrpc_dummy_notify_rx(struct sock * sk,struct rxrpc_call * rxcall,unsigned long call_user_ID)388 static void rxrpc_dummy_notify_rx(struct sock *sk, struct rxrpc_call *rxcall,
389 				  unsigned long call_user_ID)
390 {
391 }
392 
393 /**
394  * rxrpc_kernel_shutdown_call - Allow a kernel service to shut down a call it was using
395  * @sock: The socket the call is on
396  * @call: The call to end
397  *
398  * Allow a kernel service to shut down a call it was using.  The call must be
399  * complete before this is called (the call should be aborted if necessary).
400  */
rxrpc_kernel_shutdown_call(struct socket * sock,struct rxrpc_call * call)401 void rxrpc_kernel_shutdown_call(struct socket *sock, struct rxrpc_call *call)
402 {
403 	_enter("%d{%d}", call->debug_id, refcount_read(&call->ref));
404 
405 	mutex_lock(&call->user_mutex);
406 	if (!test_bit(RXRPC_CALL_RELEASED, &call->flags)) {
407 		rxrpc_release_call(rxrpc_sk(sock->sk), call);
408 
409 		/* Make sure we're not going to call back into a kernel service */
410 		if (call->notify_rx) {
411 			spin_lock(&call->notify_lock);
412 			call->notify_rx = rxrpc_dummy_notify_rx;
413 			spin_unlock(&call->notify_lock);
414 		}
415 	}
416 	mutex_unlock(&call->user_mutex);
417 }
418 EXPORT_SYMBOL(rxrpc_kernel_shutdown_call);
419 
420 /**
421  * rxrpc_kernel_put_call - Release a reference to a call
422  * @sock: The socket the call is on
423  * @call: The call to put
424  *
425  * Drop the application's ref on an rxrpc call.
426  */
rxrpc_kernel_put_call(struct socket * sock,struct rxrpc_call * call)427 void rxrpc_kernel_put_call(struct socket *sock, struct rxrpc_call *call)
428 {
429 	rxrpc_put_call(call, rxrpc_call_put_kernel);
430 }
431 EXPORT_SYMBOL(rxrpc_kernel_put_call);
432 
433 /**
434  * rxrpc_kernel_check_life - Check to see whether a call is still alive
435  * @sock: The socket the call is on
436  * @call: The call to check
437  *
438  * Allow a kernel service to find out whether a call is still alive - whether
439  * it has completed successfully and all received data has been consumed.
440  */
rxrpc_kernel_check_life(const struct socket * sock,const struct rxrpc_call * call)441 bool rxrpc_kernel_check_life(const struct socket *sock,
442 			     const struct rxrpc_call *call)
443 {
444 	if (!rxrpc_call_is_complete(call))
445 		return true;
446 	if (call->completion != RXRPC_CALL_SUCCEEDED)
447 		return false;
448 	return !skb_queue_empty(&call->recvmsg_queue);
449 }
450 EXPORT_SYMBOL(rxrpc_kernel_check_life);
451 
452 /**
453  * rxrpc_kernel_get_epoch - Retrieve the epoch value from a call.
454  * @sock: The socket the call is on
455  * @call: The call to query
456  *
457  * Allow a kernel service to retrieve the epoch value from a service call to
458  * see if the client at the other end rebooted.
459  */
rxrpc_kernel_get_epoch(struct socket * sock,struct rxrpc_call * call)460 u32 rxrpc_kernel_get_epoch(struct socket *sock, struct rxrpc_call *call)
461 {
462 	return call->conn->proto.epoch;
463 }
464 EXPORT_SYMBOL(rxrpc_kernel_get_epoch);
465 
466 /**
467  * rxrpc_kernel_new_call_notification - Get notifications of new calls
468  * @sock: The socket to intercept received messages on
469  * @notify_new_call: Function to be called when new calls appear
470  * @discard_new_call: Function to discard preallocated calls
471  *
472  * Allow a kernel service to be given notifications about new calls.
473  */
rxrpc_kernel_new_call_notification(struct socket * sock,rxrpc_notify_new_call_t notify_new_call,rxrpc_discard_new_call_t discard_new_call)474 void rxrpc_kernel_new_call_notification(
475 	struct socket *sock,
476 	rxrpc_notify_new_call_t notify_new_call,
477 	rxrpc_discard_new_call_t discard_new_call)
478 {
479 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
480 
481 	rx->notify_new_call = notify_new_call;
482 	rx->discard_new_call = discard_new_call;
483 }
484 EXPORT_SYMBOL(rxrpc_kernel_new_call_notification);
485 
486 /**
487  * rxrpc_kernel_set_max_life - Set maximum lifespan on a call
488  * @sock: The socket the call is on
489  * @call: The call to configure
490  * @hard_timeout: The maximum lifespan of the call in ms
491  *
492  * Set the maximum lifespan of a call.  The call will end with ETIME or
493  * ETIMEDOUT if it takes longer than this.
494  */
rxrpc_kernel_set_max_life(struct socket * sock,struct rxrpc_call * call,unsigned long hard_timeout)495 void rxrpc_kernel_set_max_life(struct socket *sock, struct rxrpc_call *call,
496 			       unsigned long hard_timeout)
497 {
498 	ktime_t delay = ms_to_ktime(hard_timeout), expect_term_by;
499 
500 	mutex_lock(&call->user_mutex);
501 
502 	expect_term_by = ktime_add(ktime_get_real(), delay);
503 	WRITE_ONCE(call->expect_term_by, expect_term_by);
504 	trace_rxrpc_timer_set(call, delay, rxrpc_timer_trace_hard);
505 	rxrpc_poke_call(call, rxrpc_call_poke_set_timeout);
506 
507 	mutex_unlock(&call->user_mutex);
508 }
509 EXPORT_SYMBOL(rxrpc_kernel_set_max_life);
510 
511 /*
512  * connect an RxRPC socket
513  * - this just targets it at a specific destination; no actual connection
514  *   negotiation takes place
515  */
rxrpc_connect(struct socket * sock,struct sockaddr * addr,int addr_len,int flags)516 static int rxrpc_connect(struct socket *sock, struct sockaddr *addr,
517 			 int addr_len, int flags)
518 {
519 	struct sockaddr_rxrpc *srx = (struct sockaddr_rxrpc *)addr;
520 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
521 	int ret;
522 
523 	_enter("%p,%p,%d,%d", rx, addr, addr_len, flags);
524 
525 	ret = rxrpc_validate_address(rx, srx, addr_len);
526 	if (ret < 0) {
527 		_leave(" = %d [bad addr]", ret);
528 		return ret;
529 	}
530 
531 	lock_sock(&rx->sk);
532 
533 	ret = -EISCONN;
534 	if (test_bit(RXRPC_SOCK_CONNECTED, &rx->flags))
535 		goto error;
536 
537 	switch (rx->sk.sk_state) {
538 	case RXRPC_UNBOUND:
539 		rx->sk.sk_state = RXRPC_CLIENT_UNBOUND;
540 		break;
541 	case RXRPC_CLIENT_UNBOUND:
542 	case RXRPC_CLIENT_BOUND:
543 		break;
544 	default:
545 		ret = -EBUSY;
546 		goto error;
547 	}
548 
549 	rx->connect_srx = *srx;
550 	set_bit(RXRPC_SOCK_CONNECTED, &rx->flags);
551 	ret = 0;
552 
553 error:
554 	release_sock(&rx->sk);
555 	return ret;
556 }
557 
558 /*
559  * send a message through an RxRPC socket
560  * - in a client this does a number of things:
561  *   - finds/sets up a connection for the security specified (if any)
562  *   - initiates a call (ID in control data)
563  *   - ends the request phase of a call (if MSG_MORE is not set)
564  *   - sends a call data packet
565  *   - may send an abort (abort code in control data)
566  */
rxrpc_sendmsg(struct socket * sock,struct msghdr * m,size_t len)567 static int rxrpc_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
568 {
569 	struct rxrpc_local *local;
570 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
571 	int ret;
572 
573 	_enter(",{%d},,%zu", rx->sk.sk_state, len);
574 
575 	if (m->msg_flags & MSG_OOB)
576 		return -EOPNOTSUPP;
577 
578 	if (m->msg_name) {
579 		ret = rxrpc_validate_address(rx, m->msg_name, m->msg_namelen);
580 		if (ret < 0) {
581 			_leave(" = %d [bad addr]", ret);
582 			return ret;
583 		}
584 	}
585 
586 	lock_sock(&rx->sk);
587 
588 	switch (rx->sk.sk_state) {
589 	case RXRPC_UNBOUND:
590 	case RXRPC_CLIENT_UNBOUND:
591 		rx->srx.srx_family = AF_RXRPC;
592 		rx->srx.srx_service = 0;
593 		rx->srx.transport_type = SOCK_DGRAM;
594 		rx->srx.transport.family = rx->family;
595 		switch (rx->family) {
596 		case AF_INET:
597 			rx->srx.transport_len = sizeof(struct sockaddr_in);
598 			break;
599 #ifdef CONFIG_AF_RXRPC_IPV6
600 		case AF_INET6:
601 			rx->srx.transport_len = sizeof(struct sockaddr_in6);
602 			break;
603 #endif
604 		default:
605 			ret = -EAFNOSUPPORT;
606 			goto error_unlock;
607 		}
608 		local = rxrpc_lookup_local(sock_net(sock->sk), &rx->srx);
609 		if (IS_ERR(local)) {
610 			ret = PTR_ERR(local);
611 			goto error_unlock;
612 		}
613 
614 		rx->local = local;
615 		rx->sk.sk_state = RXRPC_CLIENT_BOUND;
616 		fallthrough;
617 
618 	case RXRPC_CLIENT_BOUND:
619 		if (!m->msg_name &&
620 		    test_bit(RXRPC_SOCK_CONNECTED, &rx->flags)) {
621 			m->msg_name = &rx->connect_srx;
622 			m->msg_namelen = sizeof(rx->connect_srx);
623 		}
624 		fallthrough;
625 	case RXRPC_SERVER_BOUND:
626 	case RXRPC_SERVER_LISTENING:
627 		ret = rxrpc_do_sendmsg(rx, m, len);
628 		/* The socket has been unlocked */
629 		goto out;
630 	default:
631 		ret = -EINVAL;
632 		goto error_unlock;
633 	}
634 
635 error_unlock:
636 	release_sock(&rx->sk);
637 out:
638 	_leave(" = %d", ret);
639 	return ret;
640 }
641 
rxrpc_sock_set_min_security_level(struct sock * sk,unsigned int val)642 int rxrpc_sock_set_min_security_level(struct sock *sk, unsigned int val)
643 {
644 	if (sk->sk_state != RXRPC_UNBOUND)
645 		return -EISCONN;
646 	if (val > RXRPC_SECURITY_MAX)
647 		return -EINVAL;
648 	lock_sock(sk);
649 	rxrpc_sk(sk)->min_sec_level = val;
650 	release_sock(sk);
651 	return 0;
652 }
653 EXPORT_SYMBOL(rxrpc_sock_set_min_security_level);
654 
655 /*
656  * set RxRPC socket options
657  */
rxrpc_setsockopt(struct socket * sock,int level,int optname,sockptr_t optval,unsigned int optlen)658 static int rxrpc_setsockopt(struct socket *sock, int level, int optname,
659 			    sockptr_t optval, unsigned int optlen)
660 {
661 	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
662 	unsigned int min_sec_level;
663 	u16 service_upgrade[2];
664 	int ret;
665 
666 	_enter(",%d,%d,,%d", level, optname, optlen);
667 
668 	lock_sock(&rx->sk);
669 	ret = -EOPNOTSUPP;
670 
671 	if (level == SOL_RXRPC) {
672 		switch (optname) {
673 		case RXRPC_EXCLUSIVE_CONNECTION:
674 			ret = -EINVAL;
675 			if (optlen != 0)
676 				goto error;
677 			ret = -EISCONN;
678 			if (rx->sk.sk_state != RXRPC_UNBOUND)
679 				goto error;
680 			rx->exclusive = true;
681 			goto success;
682 
683 		case RXRPC_SECURITY_KEY:
684 			ret = -EINVAL;
685 			if (rx->key)
686 				goto error;
687 			ret = -EISCONN;
688 			if (rx->sk.sk_state != RXRPC_UNBOUND)
689 				goto error;
690 			ret = rxrpc_request_key(rx, optval, optlen);
691 			goto error;
692 
693 		case RXRPC_SECURITY_KEYRING:
694 			ret = -EINVAL;
695 			if (rx->key)
696 				goto error;
697 			ret = -EISCONN;
698 			if (rx->sk.sk_state != RXRPC_UNBOUND)
699 				goto error;
700 			ret = rxrpc_server_keyring(rx, optval, optlen);
701 			goto error;
702 
703 		case RXRPC_MIN_SECURITY_LEVEL:
704 			ret = -EINVAL;
705 			if (optlen != sizeof(unsigned int))
706 				goto error;
707 			ret = -EISCONN;
708 			if (rx->sk.sk_state != RXRPC_UNBOUND)
709 				goto error;
710 			ret = copy_safe_from_sockptr(&min_sec_level,
711 						     sizeof(min_sec_level),
712 						     optval, optlen);
713 			if (ret)
714 				goto error;
715 			ret = -EINVAL;
716 			if (min_sec_level > RXRPC_SECURITY_MAX)
717 				goto error;
718 			rx->min_sec_level = min_sec_level;
719 			goto success;
720 
721 		case RXRPC_UPGRADEABLE_SERVICE:
722 			ret = -EINVAL;
723 			if (optlen != sizeof(service_upgrade) ||
724 			    rx->service_upgrade.from != 0)
725 				goto error;
726 			ret = -EISCONN;
727 			if (rx->sk.sk_state != RXRPC_SERVER_BOUND2)
728 				goto error;
729 			ret = -EFAULT;
730 			if (copy_from_sockptr(service_upgrade, optval,
731 					   sizeof(service_upgrade)) != 0)
732 				goto error;
733 			ret = -EINVAL;
734 			if ((service_upgrade[0] != rx->srx.srx_service ||
735 			     service_upgrade[1] != rx->second_service) &&
736 			    (service_upgrade[0] != rx->second_service ||
737 			     service_upgrade[1] != rx->srx.srx_service))
738 				goto error;
739 			rx->service_upgrade.from = service_upgrade[0];
740 			rx->service_upgrade.to = service_upgrade[1];
741 			goto success;
742 
743 		default:
744 			break;
745 		}
746 	}
747 
748 success:
749 	ret = 0;
750 error:
751 	release_sock(&rx->sk);
752 	return ret;
753 }
754 
755 /*
756  * Get socket options.
757  */
rxrpc_getsockopt(struct socket * sock,int level,int optname,char __user * optval,int __user * _optlen)758 static int rxrpc_getsockopt(struct socket *sock, int level, int optname,
759 			    char __user *optval, int __user *_optlen)
760 {
761 	int optlen;
762 
763 	if (level != SOL_RXRPC)
764 		return -EOPNOTSUPP;
765 
766 	if (get_user(optlen, _optlen))
767 		return -EFAULT;
768 
769 	switch (optname) {
770 	case RXRPC_SUPPORTED_CMSG:
771 		if (optlen < sizeof(int))
772 			return -ETOOSMALL;
773 		if (put_user(RXRPC__SUPPORTED - 1, (int __user *)optval) ||
774 		    put_user(sizeof(int), _optlen))
775 			return -EFAULT;
776 		return 0;
777 
778 	default:
779 		return -EOPNOTSUPP;
780 	}
781 }
782 
783 /*
784  * permit an RxRPC socket to be polled
785  */
rxrpc_poll(struct file * file,struct socket * sock,poll_table * wait)786 static __poll_t rxrpc_poll(struct file *file, struct socket *sock,
787 			       poll_table *wait)
788 {
789 	struct sock *sk = sock->sk;
790 	struct rxrpc_sock *rx = rxrpc_sk(sk);
791 	__poll_t mask;
792 
793 	sock_poll_wait(file, sock, wait);
794 	mask = 0;
795 
796 	/* the socket is readable if there are any messages waiting on the Rx
797 	 * queue */
798 	if (!list_empty(&rx->recvmsg_q))
799 		mask |= EPOLLIN | EPOLLRDNORM;
800 
801 	/* the socket is writable if there is space to add new data to the
802 	 * socket; there is no guarantee that any particular call in progress
803 	 * on the socket may have space in the Tx ACK window */
804 	if (rxrpc_writable(sk))
805 		mask |= EPOLLOUT | EPOLLWRNORM;
806 
807 	return mask;
808 }
809 
810 /*
811  * create an RxRPC socket
812  */
rxrpc_create(struct net * net,struct socket * sock,int protocol,int kern)813 static int rxrpc_create(struct net *net, struct socket *sock, int protocol,
814 			int kern)
815 {
816 	struct rxrpc_net *rxnet;
817 	struct rxrpc_sock *rx;
818 	struct sock *sk;
819 
820 	_enter("%p,%d", sock, protocol);
821 
822 	/* we support transport protocol UDP/UDP6 only */
823 	if (protocol != PF_INET &&
824 	    IS_ENABLED(CONFIG_AF_RXRPC_IPV6) && protocol != PF_INET6)
825 		return -EPROTONOSUPPORT;
826 
827 	if (sock->type != SOCK_DGRAM)
828 		return -ESOCKTNOSUPPORT;
829 
830 	sock->ops = &rxrpc_rpc_ops;
831 	sock->state = SS_UNCONNECTED;
832 
833 	sk = sk_alloc(net, PF_RXRPC, GFP_KERNEL, &rxrpc_proto, kern);
834 	if (!sk)
835 		return -ENOMEM;
836 
837 	sock_init_data(sock, sk);
838 	sock_set_flag(sk, SOCK_RCU_FREE);
839 	sk->sk_state		= RXRPC_UNBOUND;
840 	sk->sk_write_space	= rxrpc_write_space;
841 	sk->sk_max_ack_backlog	= 0;
842 	sk->sk_destruct		= rxrpc_sock_destructor;
843 
844 	rx = rxrpc_sk(sk);
845 	rx->family = protocol;
846 	rx->calls = RB_ROOT;
847 
848 	spin_lock_init(&rx->incoming_lock);
849 	INIT_LIST_HEAD(&rx->sock_calls);
850 	INIT_LIST_HEAD(&rx->to_be_accepted);
851 	INIT_LIST_HEAD(&rx->recvmsg_q);
852 	spin_lock_init(&rx->recvmsg_lock);
853 	rwlock_init(&rx->call_lock);
854 	memset(&rx->srx, 0, sizeof(rx->srx));
855 
856 	rxnet = rxrpc_net(sock_net(&rx->sk));
857 	timer_reduce(&rxnet->peer_keepalive_timer, jiffies + 1);
858 
859 	_leave(" = 0 [%p]", rx);
860 	return 0;
861 }
862 
863 /*
864  * Kill all the calls on a socket and shut it down.
865  */
rxrpc_shutdown(struct socket * sock,int flags)866 static int rxrpc_shutdown(struct socket *sock, int flags)
867 {
868 	struct sock *sk = sock->sk;
869 	struct rxrpc_sock *rx = rxrpc_sk(sk);
870 	int ret = 0;
871 
872 	_enter("%p,%d", sk, flags);
873 
874 	if (flags != SHUT_RDWR)
875 		return -EOPNOTSUPP;
876 	if (sk->sk_state == RXRPC_CLOSE)
877 		return -ESHUTDOWN;
878 
879 	lock_sock(sk);
880 
881 	if (sk->sk_state < RXRPC_CLOSE) {
882 		sk->sk_state = RXRPC_CLOSE;
883 		sk->sk_shutdown = SHUTDOWN_MASK;
884 	} else {
885 		ret = -ESHUTDOWN;
886 	}
887 
888 	rxrpc_discard_prealloc(rx);
889 
890 	release_sock(sk);
891 	return ret;
892 }
893 
894 /*
895  * RxRPC socket destructor
896  */
rxrpc_sock_destructor(struct sock * sk)897 static void rxrpc_sock_destructor(struct sock *sk)
898 {
899 	_enter("%p", sk);
900 
901 	rxrpc_purge_queue(&sk->sk_receive_queue);
902 
903 	WARN_ON(refcount_read(&sk->sk_wmem_alloc));
904 	WARN_ON(!sk_unhashed(sk));
905 	WARN_ON(sk->sk_socket);
906 
907 	if (!sock_flag(sk, SOCK_DEAD)) {
908 		printk("Attempt to release alive rxrpc socket: %p\n", sk);
909 		return;
910 	}
911 }
912 
913 /*
914  * release an RxRPC socket
915  */
rxrpc_release_sock(struct sock * sk)916 static int rxrpc_release_sock(struct sock *sk)
917 {
918 	struct rxrpc_sock *rx = rxrpc_sk(sk);
919 
920 	_enter("%p{%d,%d}", sk, sk->sk_state, refcount_read(&sk->sk_refcnt));
921 
922 	/* declare the socket closed for business */
923 	sock_orphan(sk);
924 	sk->sk_shutdown = SHUTDOWN_MASK;
925 
926 	/* We want to kill off all connections from a service socket
927 	 * as fast as possible because we can't share these; client
928 	 * sockets, on the other hand, can share an endpoint.
929 	 */
930 	switch (sk->sk_state) {
931 	case RXRPC_SERVER_BOUND:
932 	case RXRPC_SERVER_BOUND2:
933 	case RXRPC_SERVER_LISTENING:
934 	case RXRPC_SERVER_LISTEN_DISABLED:
935 		rx->local->service_closed = true;
936 		break;
937 	}
938 
939 	sk->sk_state = RXRPC_CLOSE;
940 
941 	if (rx->local && rx->local->service == rx) {
942 		write_lock(&rx->local->services_lock);
943 		rx->local->service = NULL;
944 		write_unlock(&rx->local->services_lock);
945 	}
946 
947 	/* try to flush out this socket */
948 	rxrpc_discard_prealloc(rx);
949 	rxrpc_release_calls_on_socket(rx);
950 	flush_workqueue(rxrpc_workqueue);
951 	rxrpc_purge_queue(&sk->sk_receive_queue);
952 
953 	rxrpc_unuse_local(rx->local, rxrpc_local_unuse_release_sock);
954 	rxrpc_put_local(rx->local, rxrpc_local_put_release_sock);
955 	rx->local = NULL;
956 	key_put(rx->key);
957 	rx->key = NULL;
958 	key_put(rx->securities);
959 	rx->securities = NULL;
960 	sock_put(sk);
961 
962 	_leave(" = 0");
963 	return 0;
964 }
965 
966 /*
967  * release an RxRPC BSD socket on close() or equivalent
968  */
rxrpc_release(struct socket * sock)969 static int rxrpc_release(struct socket *sock)
970 {
971 	struct sock *sk = sock->sk;
972 
973 	_enter("%p{%p}", sock, sk);
974 
975 	if (!sk)
976 		return 0;
977 
978 	sock->sk = NULL;
979 
980 	return rxrpc_release_sock(sk);
981 }
982 
983 /*
984  * RxRPC network protocol
985  */
986 static const struct proto_ops rxrpc_rpc_ops = {
987 	.family		= PF_RXRPC,
988 	.owner		= THIS_MODULE,
989 	.release	= rxrpc_release,
990 	.bind		= rxrpc_bind,
991 	.connect	= rxrpc_connect,
992 	.socketpair	= sock_no_socketpair,
993 	.accept		= sock_no_accept,
994 	.getname	= sock_no_getname,
995 	.poll		= rxrpc_poll,
996 	.ioctl		= sock_no_ioctl,
997 	.listen		= rxrpc_listen,
998 	.shutdown	= rxrpc_shutdown,
999 	.setsockopt	= rxrpc_setsockopt,
1000 	.getsockopt	= rxrpc_getsockopt,
1001 	.sendmsg	= rxrpc_sendmsg,
1002 	.recvmsg	= rxrpc_recvmsg,
1003 	.mmap		= sock_no_mmap,
1004 };
1005 
1006 static struct proto rxrpc_proto = {
1007 	.name		= "RXRPC",
1008 	.owner		= THIS_MODULE,
1009 	.obj_size	= sizeof(struct rxrpc_sock),
1010 	.max_header	= sizeof(struct rxrpc_wire_header),
1011 };
1012 
1013 static const struct net_proto_family rxrpc_family_ops = {
1014 	.family	= PF_RXRPC,
1015 	.create = rxrpc_create,
1016 	.owner	= THIS_MODULE,
1017 };
1018 
1019 /*
1020  * initialise and register the RxRPC protocol
1021  */
af_rxrpc_init(void)1022 static int __init af_rxrpc_init(void)
1023 {
1024 	int ret = -1;
1025 
1026 	BUILD_BUG_ON(sizeof(struct rxrpc_skb_priv) > sizeof_field(struct sk_buff, cb));
1027 
1028 	ret = -ENOMEM;
1029 	rxrpc_gen_version_string();
1030 	rxrpc_call_jar = kmem_cache_create(
1031 		"rxrpc_call_jar", sizeof(struct rxrpc_call), 0,
1032 		SLAB_HWCACHE_ALIGN, NULL);
1033 	if (!rxrpc_call_jar) {
1034 		pr_notice("Failed to allocate call jar\n");
1035 		goto error_call_jar;
1036 	}
1037 
1038 	rxrpc_workqueue = alloc_ordered_workqueue("krxrpcd", WQ_HIGHPRI | WQ_MEM_RECLAIM);
1039 	if (!rxrpc_workqueue) {
1040 		pr_notice("Failed to allocate work queue\n");
1041 		goto error_work_queue;
1042 	}
1043 
1044 	ret = rxrpc_init_security();
1045 	if (ret < 0) {
1046 		pr_crit("Cannot initialise security\n");
1047 		goto error_security;
1048 	}
1049 
1050 	ret = register_pernet_device(&rxrpc_net_ops);
1051 	if (ret)
1052 		goto error_pernet;
1053 
1054 	ret = proto_register(&rxrpc_proto, 1);
1055 	if (ret < 0) {
1056 		pr_crit("Cannot register protocol\n");
1057 		goto error_proto;
1058 	}
1059 
1060 	ret = sock_register(&rxrpc_family_ops);
1061 	if (ret < 0) {
1062 		pr_crit("Cannot register socket family\n");
1063 		goto error_sock;
1064 	}
1065 
1066 	ret = register_key_type(&key_type_rxrpc);
1067 	if (ret < 0) {
1068 		pr_crit("Cannot register client key type\n");
1069 		goto error_key_type;
1070 	}
1071 
1072 	ret = register_key_type(&key_type_rxrpc_s);
1073 	if (ret < 0) {
1074 		pr_crit("Cannot register server key type\n");
1075 		goto error_key_type_s;
1076 	}
1077 
1078 	ret = rxrpc_sysctl_init();
1079 	if (ret < 0) {
1080 		pr_crit("Cannot register sysctls\n");
1081 		goto error_sysctls;
1082 	}
1083 
1084 	return 0;
1085 
1086 error_sysctls:
1087 	unregister_key_type(&key_type_rxrpc_s);
1088 error_key_type_s:
1089 	unregister_key_type(&key_type_rxrpc);
1090 error_key_type:
1091 	sock_unregister(PF_RXRPC);
1092 error_sock:
1093 	proto_unregister(&rxrpc_proto);
1094 error_proto:
1095 	unregister_pernet_device(&rxrpc_net_ops);
1096 error_pernet:
1097 	rxrpc_exit_security();
1098 error_security:
1099 	destroy_workqueue(rxrpc_workqueue);
1100 error_work_queue:
1101 	kmem_cache_destroy(rxrpc_call_jar);
1102 error_call_jar:
1103 	return ret;
1104 }
1105 
1106 /*
1107  * unregister the RxRPC protocol
1108  */
af_rxrpc_exit(void)1109 static void __exit af_rxrpc_exit(void)
1110 {
1111 	_enter("");
1112 	rxrpc_sysctl_exit();
1113 	unregister_key_type(&key_type_rxrpc_s);
1114 	unregister_key_type(&key_type_rxrpc);
1115 	sock_unregister(PF_RXRPC);
1116 	proto_unregister(&rxrpc_proto);
1117 	unregister_pernet_device(&rxrpc_net_ops);
1118 	ASSERTCMP(atomic_read(&rxrpc_n_rx_skbs), ==, 0);
1119 
1120 	/* Make sure the local and peer records pinned by any dying connections
1121 	 * are released.
1122 	 */
1123 	rcu_barrier();
1124 
1125 	destroy_workqueue(rxrpc_workqueue);
1126 	rxrpc_exit_security();
1127 	kmem_cache_destroy(rxrpc_call_jar);
1128 	_leave("");
1129 }
1130 
1131 module_init(af_rxrpc_init);
1132 module_exit(af_rxrpc_exit);
1133