xref: /linux/net/llc/af_llc.c (revision 65ae975e97d5aab3ee9dc5ec701b12090572ed43)
1 /*
2  * af_llc.c - LLC User Interface SAPs
3  * Description:
4  *   Functions in this module are implementation of socket based llc
5  *   communications for the Linux operating system. Support of llc class
6  *   one and class two is provided via SOCK_DGRAM and SOCK_STREAM
7  *   respectively.
8  *
9  *   An llc2 connection is (mac + sap), only one llc2 sap connection
10  *   is allowed per mac. Though one sap may have multiple mac + sap
11  *   connections.
12  *
13  * Copyright (c) 2001 by Jay Schulist <jschlst@samba.org>
14  *		 2002-2003 by Arnaldo Carvalho de Melo <acme@conectiva.com.br>
15  *
16  * This program can be redistributed or modified under the terms of the
17  * GNU General Public License as published by the Free Software Foundation.
18  * This program is distributed without any warranty or implied warranty
19  * of merchantability or fitness for a particular purpose.
20  *
21  * See the GNU General Public License for more details.
22  */
23 #include <linux/compiler.h>
24 #include <linux/kernel.h>
25 #include <linux/module.h>
26 #include <linux/rtnetlink.h>
27 #include <linux/init.h>
28 #include <linux/slab.h>
29 #include <linux/sched/signal.h>
30 
31 #include <net/llc.h>
32 #include <net/llc_sap.h>
33 #include <net/llc_pdu.h>
34 #include <net/llc_conn.h>
35 #include <net/tcp_states.h>
36 
37 /* remember: uninitialized global data is zeroed because its in .bss */
38 static u16 llc_ui_sap_last_autoport = LLC_SAP_DYN_START;
39 static u16 llc_ui_sap_link_no_max[256];
40 static struct sockaddr_llc llc_ui_addrnull;
41 static const struct proto_ops llc_ui_ops;
42 
43 static bool llc_ui_wait_for_conn(struct sock *sk, long timeout);
44 static int llc_ui_wait_for_disc(struct sock *sk, long timeout);
45 static int llc_ui_wait_for_busy_core(struct sock *sk, long timeout);
46 
47 #if 0
48 #define dprintk(args...) printk(KERN_DEBUG args)
49 #else
50 #define dprintk(args...) do {} while (0)
51 #endif
52 
53 /* Maybe we'll add some more in the future. */
54 #define LLC_CMSG_PKTINFO	1
55 
56 
57 /**
58  *	llc_ui_next_link_no - return the next unused link number for a sap
59  *	@sap: Address of sap to get link number from.
60  *
61  *	Return the next unused link number for a given sap.
62  */
llc_ui_next_link_no(int sap)63 static inline u16 llc_ui_next_link_no(int sap)
64 {
65 	return llc_ui_sap_link_no_max[sap]++;
66 }
67 
68 /**
69  *	llc_proto_type - return eth protocol for ARP header type
70  *	@arphrd: ARP header type.
71  *
72  *	Given an ARP header type return the corresponding ethernet protocol.
73  */
llc_proto_type(u16 arphrd)74 static inline __be16 llc_proto_type(u16 arphrd)
75 {
76 	return htons(ETH_P_802_2);
77 }
78 
79 /**
80  *	llc_ui_addr_null - determines if a address structure is null
81  *	@addr: Address to test if null.
82  */
llc_ui_addr_null(struct sockaddr_llc * addr)83 static inline u8 llc_ui_addr_null(struct sockaddr_llc *addr)
84 {
85 	return !memcmp(addr, &llc_ui_addrnull, sizeof(*addr));
86 }
87 
88 /**
89  *	llc_ui_header_len - return length of llc header based on operation
90  *	@sk: Socket which contains a valid llc socket type.
91  *	@addr: Complete sockaddr_llc structure received from the user.
92  *
93  *	Provide the length of the llc header depending on what kind of
94  *	operation the user would like to perform and the type of socket.
95  *	Returns the correct llc header length.
96  */
llc_ui_header_len(struct sock * sk,struct sockaddr_llc * addr)97 static inline u8 llc_ui_header_len(struct sock *sk, struct sockaddr_llc *addr)
98 {
99 	u8 rc = LLC_PDU_LEN_U;
100 
101 	if (addr->sllc_test)
102 		rc = LLC_PDU_LEN_U;
103 	else if (addr->sllc_xid)
104 		/* We need to expand header to sizeof(struct llc_xid_info)
105 		 * since llc_pdu_init_as_xid_cmd() sets 4,5,6 bytes of LLC header
106 		 * as XID PDU. In llc_ui_sendmsg() we reserved header size and then
107 		 * filled all other space with user data. If we won't reserve this
108 		 * bytes, llc_pdu_init_as_xid_cmd() will overwrite user data
109 		 */
110 		rc = LLC_PDU_LEN_U_XID;
111 	else if (sk->sk_type == SOCK_STREAM)
112 		rc = LLC_PDU_LEN_I;
113 	return rc;
114 }
115 
116 /**
117  *	llc_ui_send_data - send data via reliable llc2 connection
118  *	@sk: Connection the socket is using.
119  *	@skb: Data the user wishes to send.
120  *	@noblock: can we block waiting for data?
121  *
122  *	Send data via reliable llc2 connection.
123  *	Returns 0 upon success, non-zero if action did not succeed.
124  *
125  *	This function always consumes a reference to the skb.
126  */
llc_ui_send_data(struct sock * sk,struct sk_buff * skb,int noblock)127 static int llc_ui_send_data(struct sock* sk, struct sk_buff *skb, int noblock)
128 {
129 	struct llc_sock* llc = llc_sk(sk);
130 
131 	if (unlikely(llc_data_accept_state(llc->state) ||
132 		     llc->remote_busy_flag ||
133 		     llc->p_flag)) {
134 		long timeout = sock_sndtimeo(sk, noblock);
135 		int rc;
136 
137 		rc = llc_ui_wait_for_busy_core(sk, timeout);
138 		if (rc) {
139 			kfree_skb(skb);
140 			return rc;
141 		}
142 	}
143 	return llc_build_and_send_pkt(sk, skb);
144 }
145 
llc_ui_sk_init(struct socket * sock,struct sock * sk)146 static void llc_ui_sk_init(struct socket *sock, struct sock *sk)
147 {
148 	sock_graft(sk, sock);
149 	sk->sk_type	= sock->type;
150 	sock->ops	= &llc_ui_ops;
151 }
152 
153 static struct proto llc_proto = {
154 	.name	  = "LLC",
155 	.owner	  = THIS_MODULE,
156 	.obj_size = sizeof(struct llc_sock),
157 	.slab_flags = SLAB_TYPESAFE_BY_RCU,
158 };
159 
160 /**
161  *	llc_ui_create - alloc and init a new llc_ui socket
162  *	@net: network namespace (must be default network)
163  *	@sock: Socket to initialize and attach allocated sk to.
164  *	@protocol: Unused.
165  *	@kern: on behalf of kernel or userspace
166  *
167  *	Allocate and initialize a new llc_ui socket, validate the user wants a
168  *	socket type we have available.
169  *	Returns 0 upon success, negative upon failure.
170  */
llc_ui_create(struct net * net,struct socket * sock,int protocol,int kern)171 static int llc_ui_create(struct net *net, struct socket *sock, int protocol,
172 			 int kern)
173 {
174 	struct sock *sk;
175 	int rc = -ESOCKTNOSUPPORT;
176 
177 	if (!ns_capable(net->user_ns, CAP_NET_RAW))
178 		return -EPERM;
179 
180 	if (!net_eq(net, &init_net))
181 		return -EAFNOSUPPORT;
182 
183 	if (likely(sock->type == SOCK_DGRAM || sock->type == SOCK_STREAM)) {
184 		rc = -ENOMEM;
185 		sk = llc_sk_alloc(net, PF_LLC, GFP_KERNEL, &llc_proto, kern);
186 		if (sk) {
187 			rc = 0;
188 			llc_ui_sk_init(sock, sk);
189 		}
190 	}
191 	return rc;
192 }
193 
194 /**
195  *	llc_ui_release - shutdown socket
196  *	@sock: Socket to release.
197  *
198  *	Shutdown and deallocate an existing socket.
199  */
llc_ui_release(struct socket * sock)200 static int llc_ui_release(struct socket *sock)
201 {
202 	struct sock *sk = sock->sk;
203 	struct llc_sock *llc;
204 
205 	if (unlikely(sk == NULL))
206 		goto out;
207 	sock_hold(sk);
208 	lock_sock(sk);
209 	llc = llc_sk(sk);
210 	dprintk("%s: closing local(%02X) remote(%02X)\n", __func__,
211 		llc->laddr.lsap, llc->daddr.lsap);
212 	if (!llc_send_disc(sk))
213 		llc_ui_wait_for_disc(sk, sk->sk_rcvtimeo);
214 	if (!sock_flag(sk, SOCK_ZAPPED)) {
215 		struct llc_sap *sap = llc->sap;
216 
217 		/* Hold this for release_sock(), so that llc_backlog_rcv()
218 		 * could still use it.
219 		 */
220 		llc_sap_hold(sap);
221 		llc_sap_remove_socket(llc->sap, sk);
222 		release_sock(sk);
223 		llc_sap_put(sap);
224 	} else {
225 		release_sock(sk);
226 	}
227 	netdev_put(llc->dev, &llc->dev_tracker);
228 	sock_put(sk);
229 	sock_orphan(sk);
230 	sock->sk = NULL;
231 	llc_sk_free(sk);
232 out:
233 	return 0;
234 }
235 
236 /**
237  *	llc_ui_autoport - provide dynamically allocate SAP number
238  *
239  *	Provide the caller with a dynamically allocated SAP number according
240  *	to the rules that are set in this function. Returns: 0, upon failure,
241  *	SAP number otherwise.
242  */
llc_ui_autoport(void)243 static int llc_ui_autoport(void)
244 {
245 	struct llc_sap *sap;
246 	int i, tries = 0;
247 
248 	while (tries < LLC_SAP_DYN_TRIES) {
249 		for (i = llc_ui_sap_last_autoport;
250 		     i < LLC_SAP_DYN_STOP; i += 2) {
251 			sap = llc_sap_find(i);
252 			if (!sap) {
253 				llc_ui_sap_last_autoport = i + 2;
254 				goto out;
255 			}
256 			llc_sap_put(sap);
257 		}
258 		llc_ui_sap_last_autoport = LLC_SAP_DYN_START;
259 		tries++;
260 	}
261 	i = 0;
262 out:
263 	return i;
264 }
265 
266 /**
267  *	llc_ui_autobind - automatically bind a socket to a sap
268  *	@sock: socket to bind
269  *	@addr: address to connect to
270  *
271  * 	Used by llc_ui_connect and llc_ui_sendmsg when the user hasn't
272  * 	specifically used llc_ui_bind to bind to an specific address/sap
273  *
274  *	Returns: 0 upon success, negative otherwise.
275  */
llc_ui_autobind(struct socket * sock,struct sockaddr_llc * addr)276 static int llc_ui_autobind(struct socket *sock, struct sockaddr_llc *addr)
277 {
278 	struct sock *sk = sock->sk;
279 	struct llc_sock *llc = llc_sk(sk);
280 	struct net_device *dev = NULL;
281 	struct llc_sap *sap;
282 	int rc = -EINVAL;
283 
284 	if (!sock_flag(sk, SOCK_ZAPPED))
285 		goto out;
286 	if (!addr->sllc_arphrd)
287 		addr->sllc_arphrd = ARPHRD_ETHER;
288 	if (addr->sllc_arphrd != ARPHRD_ETHER)
289 		goto out;
290 	rc = -ENODEV;
291 	if (sk->sk_bound_dev_if) {
292 		dev = dev_get_by_index(&init_net, sk->sk_bound_dev_if);
293 		if (dev && addr->sllc_arphrd != dev->type) {
294 			dev_put(dev);
295 			dev = NULL;
296 		}
297 	} else
298 		dev = dev_getfirstbyhwtype(&init_net, addr->sllc_arphrd);
299 	if (!dev)
300 		goto out;
301 	rc = -EUSERS;
302 	llc->laddr.lsap = llc_ui_autoport();
303 	if (!llc->laddr.lsap)
304 		goto out;
305 	rc = -EBUSY; /* some other network layer is using the sap */
306 	sap = llc_sap_open(llc->laddr.lsap, NULL);
307 	if (!sap)
308 		goto out;
309 
310 	/* Note: We do not expect errors from this point. */
311 	llc->dev = dev;
312 	netdev_tracker_alloc(llc->dev, &llc->dev_tracker, GFP_KERNEL);
313 	dev = NULL;
314 
315 	memcpy(llc->laddr.mac, llc->dev->dev_addr, IFHWADDRLEN);
316 	memcpy(&llc->addr, addr, sizeof(llc->addr));
317 	/* assign new connection to its SAP */
318 	llc_sap_add_socket(sap, sk);
319 	sock_reset_flag(sk, SOCK_ZAPPED);
320 	rc = 0;
321 out:
322 	dev_put(dev);
323 	return rc;
324 }
325 
326 /**
327  *	llc_ui_bind - bind a socket to a specific address.
328  *	@sock: Socket to bind an address to.
329  *	@uaddr: Address the user wants the socket bound to.
330  *	@addrlen: Length of the uaddr structure.
331  *
332  *	Bind a socket to a specific address. For llc a user is able to bind to
333  *	a specific sap only or mac + sap.
334  *	If the user desires to bind to a specific mac + sap, it is possible to
335  *	have multiple sap connections via multiple macs.
336  *	Bind and autobind for that matter must enforce the correct sap usage
337  *	otherwise all hell will break loose.
338  *	Returns: 0 upon success, negative otherwise.
339  */
llc_ui_bind(struct socket * sock,struct sockaddr * uaddr,int addrlen)340 static int llc_ui_bind(struct socket *sock, struct sockaddr *uaddr, int addrlen)
341 {
342 	struct sockaddr_llc *addr = (struct sockaddr_llc *)uaddr;
343 	struct sock *sk = sock->sk;
344 	struct llc_sock *llc = llc_sk(sk);
345 	struct net_device *dev = NULL;
346 	struct llc_sap *sap;
347 	int rc = -EINVAL;
348 
349 	lock_sock(sk);
350 	if (unlikely(!sock_flag(sk, SOCK_ZAPPED) || addrlen != sizeof(*addr)))
351 		goto out;
352 	rc = -EAFNOSUPPORT;
353 	if (!addr->sllc_arphrd)
354 		addr->sllc_arphrd = ARPHRD_ETHER;
355 	if (unlikely(addr->sllc_family != AF_LLC || addr->sllc_arphrd != ARPHRD_ETHER))
356 		goto out;
357 	dprintk("%s: binding %02X\n", __func__, addr->sllc_sap);
358 	rc = -ENODEV;
359 	rcu_read_lock();
360 	if (sk->sk_bound_dev_if) {
361 		dev = dev_get_by_index_rcu(&init_net, sk->sk_bound_dev_if);
362 		if (dev) {
363 			if (is_zero_ether_addr(addr->sllc_mac))
364 				memcpy(addr->sllc_mac, dev->dev_addr,
365 				       IFHWADDRLEN);
366 			if (addr->sllc_arphrd != dev->type ||
367 			    !ether_addr_equal(addr->sllc_mac,
368 					      dev->dev_addr)) {
369 				rc = -EINVAL;
370 				dev = NULL;
371 			}
372 		}
373 	} else {
374 		dev = dev_getbyhwaddr_rcu(&init_net, addr->sllc_arphrd,
375 					   addr->sllc_mac);
376 	}
377 	dev_hold(dev);
378 	rcu_read_unlock();
379 	if (!dev)
380 		goto out;
381 
382 	if (!addr->sllc_sap) {
383 		rc = -EUSERS;
384 		addr->sllc_sap = llc_ui_autoport();
385 		if (!addr->sllc_sap)
386 			goto out;
387 	}
388 	sap = llc_sap_find(addr->sllc_sap);
389 	if (!sap) {
390 		sap = llc_sap_open(addr->sllc_sap, NULL);
391 		rc = -EBUSY; /* some other network layer is using the sap */
392 		if (!sap)
393 			goto out;
394 	} else {
395 		struct llc_addr laddr, daddr;
396 		struct sock *ask;
397 
398 		memset(&laddr, 0, sizeof(laddr));
399 		memset(&daddr, 0, sizeof(daddr));
400 		/*
401 		 * FIXME: check if the address is multicast,
402 		 * 	  only SOCK_DGRAM can do this.
403 		 */
404 		memcpy(laddr.mac, addr->sllc_mac, IFHWADDRLEN);
405 		laddr.lsap = addr->sllc_sap;
406 		rc = -EADDRINUSE; /* mac + sap clash. */
407 		ask = llc_lookup_established(sap, &daddr, &laddr, &init_net);
408 		if (ask) {
409 			sock_put(ask);
410 			goto out_put;
411 		}
412 	}
413 
414 	/* Note: We do not expect errors from this point. */
415 	llc->dev = dev;
416 	netdev_tracker_alloc(llc->dev, &llc->dev_tracker, GFP_KERNEL);
417 	dev = NULL;
418 
419 	llc->laddr.lsap = addr->sllc_sap;
420 	memcpy(llc->laddr.mac, addr->sllc_mac, IFHWADDRLEN);
421 	memcpy(&llc->addr, addr, sizeof(llc->addr));
422 	/* assign new connection to its SAP */
423 	llc_sap_add_socket(sap, sk);
424 	sock_reset_flag(sk, SOCK_ZAPPED);
425 	rc = 0;
426 out_put:
427 	llc_sap_put(sap);
428 out:
429 	dev_put(dev);
430 	release_sock(sk);
431 	return rc;
432 }
433 
434 /**
435  *	llc_ui_shutdown - shutdown a connect llc2 socket.
436  *	@sock: Socket to shutdown.
437  *	@how: What part of the socket to shutdown.
438  *
439  *	Shutdown a connected llc2 socket. Currently this function only supports
440  *	shutting down both sends and receives (2), we could probably make this
441  *	function such that a user can shutdown only half the connection but not
442  *	right now.
443  *	Returns: 0 upon success, negative otherwise.
444  */
llc_ui_shutdown(struct socket * sock,int how)445 static int llc_ui_shutdown(struct socket *sock, int how)
446 {
447 	struct sock *sk = sock->sk;
448 	int rc = -ENOTCONN;
449 
450 	lock_sock(sk);
451 	if (unlikely(sk->sk_state != TCP_ESTABLISHED))
452 		goto out;
453 	rc = -EINVAL;
454 	if (how != 2)
455 		goto out;
456 	rc = llc_send_disc(sk);
457 	if (!rc)
458 		rc = llc_ui_wait_for_disc(sk, sk->sk_rcvtimeo);
459 	/* Wake up anyone sleeping in poll */
460 	sk->sk_state_change(sk);
461 out:
462 	release_sock(sk);
463 	return rc;
464 }
465 
466 /**
467  *	llc_ui_connect - Connect to a remote llc2 mac + sap.
468  *	@sock: Socket which will be connected to the remote destination.
469  *	@uaddr: Remote and possibly the local address of the new connection.
470  *	@addrlen: Size of uaddr structure.
471  *	@flags: Operational flags specified by the user.
472  *
473  *	Connect to a remote llc2 mac + sap. The caller must specify the
474  *	destination mac and address to connect to. If the user hasn't previously
475  *	called bind(2) with a smac the address of the first interface of the
476  *	specified arp type will be used.
477  *	This function will autobind if user did not previously call bind.
478  *	Returns: 0 upon success, negative otherwise.
479  */
llc_ui_connect(struct socket * sock,struct sockaddr * uaddr,int addrlen,int flags)480 static int llc_ui_connect(struct socket *sock, struct sockaddr *uaddr,
481 			  int addrlen, int flags)
482 {
483 	struct sock *sk = sock->sk;
484 	struct llc_sock *llc = llc_sk(sk);
485 	struct sockaddr_llc *addr = (struct sockaddr_llc *)uaddr;
486 	int rc = -EINVAL;
487 
488 	lock_sock(sk);
489 	if (unlikely(addrlen != sizeof(*addr)))
490 		goto out;
491 	rc = -EAFNOSUPPORT;
492 	if (unlikely(addr->sllc_family != AF_LLC))
493 		goto out;
494 	if (unlikely(sk->sk_type != SOCK_STREAM))
495 		goto out;
496 	rc = -EALREADY;
497 	if (unlikely(sock->state == SS_CONNECTING))
498 		goto out;
499 	/* bind connection to sap if user hasn't done it. */
500 	if (sock_flag(sk, SOCK_ZAPPED)) {
501 		/* bind to sap with null dev, exclusive */
502 		rc = llc_ui_autobind(sock, addr);
503 		if (rc)
504 			goto out;
505 	}
506 	llc->daddr.lsap = addr->sllc_sap;
507 	memcpy(llc->daddr.mac, addr->sllc_mac, IFHWADDRLEN);
508 	sock->state = SS_CONNECTING;
509 	sk->sk_state   = TCP_SYN_SENT;
510 	llc->link   = llc_ui_next_link_no(llc->sap->laddr.lsap);
511 	rc = llc_establish_connection(sk, llc->dev->dev_addr,
512 				      addr->sllc_mac, addr->sllc_sap);
513 	if (rc) {
514 		dprintk("%s: llc_ui_send_conn failed :-(\n", __func__);
515 		sock->state  = SS_UNCONNECTED;
516 		sk->sk_state = TCP_CLOSE;
517 		goto out;
518 	}
519 
520 	if (sk->sk_state == TCP_SYN_SENT) {
521 		const long timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
522 
523 		if (!timeo || !llc_ui_wait_for_conn(sk, timeo))
524 			goto out;
525 
526 		rc = sock_intr_errno(timeo);
527 		if (signal_pending(current))
528 			goto out;
529 	}
530 
531 	if (sk->sk_state == TCP_CLOSE)
532 		goto sock_error;
533 
534 	sock->state = SS_CONNECTED;
535 	rc = 0;
536 out:
537 	release_sock(sk);
538 	return rc;
539 sock_error:
540 	rc = sock_error(sk) ? : -ECONNABORTED;
541 	sock->state = SS_UNCONNECTED;
542 	goto out;
543 }
544 
545 /**
546  *	llc_ui_listen - allow a normal socket to accept incoming connections
547  *	@sock: Socket to allow incoming connections on.
548  *	@backlog: Number of connections to queue.
549  *
550  *	Allow a normal socket to accept incoming connections.
551  *	Returns 0 upon success, negative otherwise.
552  */
llc_ui_listen(struct socket * sock,int backlog)553 static int llc_ui_listen(struct socket *sock, int backlog)
554 {
555 	struct sock *sk = sock->sk;
556 	int rc = -EINVAL;
557 
558 	lock_sock(sk);
559 	if (unlikely(sock->state != SS_UNCONNECTED))
560 		goto out;
561 	rc = -EOPNOTSUPP;
562 	if (unlikely(sk->sk_type != SOCK_STREAM))
563 		goto out;
564 	rc = -EAGAIN;
565 	if (sock_flag(sk, SOCK_ZAPPED))
566 		goto out;
567 	rc = 0;
568 	if (!(unsigned int)backlog)	/* BSDism */
569 		backlog = 1;
570 	sk->sk_max_ack_backlog = backlog;
571 	if (sk->sk_state != TCP_LISTEN) {
572 		sk->sk_ack_backlog = 0;
573 		sk->sk_state	   = TCP_LISTEN;
574 	}
575 	sk->sk_socket->flags |= __SO_ACCEPTCON;
576 out:
577 	release_sock(sk);
578 	return rc;
579 }
580 
llc_ui_wait_for_disc(struct sock * sk,long timeout)581 static int llc_ui_wait_for_disc(struct sock *sk, long timeout)
582 {
583 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
584 	int rc = 0;
585 
586 	add_wait_queue(sk_sleep(sk), &wait);
587 	while (1) {
588 		if (sk_wait_event(sk, &timeout,
589 				  READ_ONCE(sk->sk_state) == TCP_CLOSE, &wait))
590 			break;
591 		rc = -ERESTARTSYS;
592 		if (signal_pending(current))
593 			break;
594 		rc = -EAGAIN;
595 		if (!timeout)
596 			break;
597 		rc = 0;
598 	}
599 	remove_wait_queue(sk_sleep(sk), &wait);
600 	return rc;
601 }
602 
llc_ui_wait_for_conn(struct sock * sk,long timeout)603 static bool llc_ui_wait_for_conn(struct sock *sk, long timeout)
604 {
605 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
606 
607 	add_wait_queue(sk_sleep(sk), &wait);
608 	while (1) {
609 		if (sk_wait_event(sk, &timeout,
610 				  READ_ONCE(sk->sk_state) != TCP_SYN_SENT, &wait))
611 			break;
612 		if (signal_pending(current) || !timeout)
613 			break;
614 	}
615 	remove_wait_queue(sk_sleep(sk), &wait);
616 	return timeout;
617 }
618 
llc_ui_wait_for_busy_core(struct sock * sk,long timeout)619 static int llc_ui_wait_for_busy_core(struct sock *sk, long timeout)
620 {
621 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
622 	struct llc_sock *llc = llc_sk(sk);
623 	int rc;
624 
625 	add_wait_queue(sk_sleep(sk), &wait);
626 	while (1) {
627 		rc = 0;
628 		if (sk_wait_event(sk, &timeout,
629 				  (READ_ONCE(sk->sk_shutdown) & RCV_SHUTDOWN) ||
630 				  (!llc_data_accept_state(llc->state) &&
631 				   !llc->remote_busy_flag &&
632 				   !llc->p_flag), &wait))
633 			break;
634 		rc = -ERESTARTSYS;
635 		if (signal_pending(current))
636 			break;
637 		rc = -EAGAIN;
638 		if (!timeout)
639 			break;
640 	}
641 	remove_wait_queue(sk_sleep(sk), &wait);
642 	return rc;
643 }
644 
llc_wait_data(struct sock * sk,long timeo)645 static int llc_wait_data(struct sock *sk, long timeo)
646 {
647 	int rc;
648 
649 	while (1) {
650 		/*
651 		 * POSIX 1003.1g mandates this order.
652 		 */
653 		rc = sock_error(sk);
654 		if (rc)
655 			break;
656 		rc = 0;
657 		if (sk->sk_shutdown & RCV_SHUTDOWN)
658 			break;
659 		rc = -EAGAIN;
660 		if (!timeo)
661 			break;
662 		rc = sock_intr_errno(timeo);
663 		if (signal_pending(current))
664 			break;
665 		rc = 0;
666 		if (sk_wait_data(sk, &timeo, NULL))
667 			break;
668 	}
669 	return rc;
670 }
671 
llc_cmsg_rcv(struct msghdr * msg,struct sk_buff * skb)672 static void llc_cmsg_rcv(struct msghdr *msg, struct sk_buff *skb)
673 {
674 	struct llc_sock *llc = llc_sk(skb->sk);
675 
676 	if (llc->cmsg_flags & LLC_CMSG_PKTINFO) {
677 		struct llc_pktinfo info;
678 
679 		memset(&info, 0, sizeof(info));
680 		info.lpi_ifindex = llc_sk(skb->sk)->dev->ifindex;
681 		llc_pdu_decode_dsap(skb, &info.lpi_sap);
682 		llc_pdu_decode_da(skb, info.lpi_mac);
683 		put_cmsg(msg, SOL_LLC, LLC_OPT_PKTINFO, sizeof(info), &info);
684 	}
685 }
686 
687 /**
688  *	llc_ui_accept - accept a new incoming connection.
689  *	@sock: Socket which connections arrive on.
690  *	@newsock: Socket to move incoming connection to.
691  *	@arg: User specified arguments
692  *
693  *	Accept a new incoming connection.
694  *	Returns 0 upon success, negative otherwise.
695  */
llc_ui_accept(struct socket * sock,struct socket * newsock,struct proto_accept_arg * arg)696 static int llc_ui_accept(struct socket *sock, struct socket *newsock,
697 			 struct proto_accept_arg *arg)
698 {
699 	struct sock *sk = sock->sk, *newsk;
700 	struct llc_sock *llc, *newllc;
701 	struct sk_buff *skb;
702 	int rc = -EOPNOTSUPP;
703 
704 	dprintk("%s: accepting on %02X\n", __func__,
705 		llc_sk(sk)->laddr.lsap);
706 	lock_sock(sk);
707 	if (unlikely(sk->sk_type != SOCK_STREAM))
708 		goto out;
709 	rc = -EINVAL;
710 	if (unlikely(sock->state != SS_UNCONNECTED ||
711 		     sk->sk_state != TCP_LISTEN))
712 		goto out;
713 	/* wait for a connection to arrive. */
714 	if (skb_queue_empty(&sk->sk_receive_queue)) {
715 		rc = llc_wait_data(sk, sk->sk_rcvtimeo);
716 		if (rc)
717 			goto out;
718 	}
719 	dprintk("%s: got a new connection on %02X\n", __func__,
720 		llc_sk(sk)->laddr.lsap);
721 	skb = skb_dequeue(&sk->sk_receive_queue);
722 	rc = -EINVAL;
723 	if (!skb->sk)
724 		goto frees;
725 	rc = 0;
726 	newsk = skb->sk;
727 	/* attach connection to a new socket. */
728 	llc_ui_sk_init(newsock, newsk);
729 	sock_reset_flag(newsk, SOCK_ZAPPED);
730 	newsk->sk_state		= TCP_ESTABLISHED;
731 	newsock->state		= SS_CONNECTED;
732 	llc			= llc_sk(sk);
733 	newllc			= llc_sk(newsk);
734 	memcpy(&newllc->addr, &llc->addr, sizeof(newllc->addr));
735 	newllc->link = llc_ui_next_link_no(newllc->laddr.lsap);
736 
737 	/* put original socket back into a clean listen state. */
738 	sk->sk_state = TCP_LISTEN;
739 	sk_acceptq_removed(sk);
740 	dprintk("%s: ok success on %02X, client on %02X\n", __func__,
741 		llc_sk(sk)->addr.sllc_sap, newllc->daddr.lsap);
742 frees:
743 	kfree_skb(skb);
744 out:
745 	release_sock(sk);
746 	return rc;
747 }
748 
749 /**
750  *	llc_ui_recvmsg - copy received data to the socket user.
751  *	@sock: Socket to copy data from.
752  *	@msg: Various user space related information.
753  *	@len: Size of user buffer.
754  *	@flags: User specified flags.
755  *
756  *	Copy received data to the socket user.
757  *	Returns non-negative upon success, negative otherwise.
758  */
llc_ui_recvmsg(struct socket * sock,struct msghdr * msg,size_t len,int flags)759 static int llc_ui_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
760 			  int flags)
761 {
762 	DECLARE_SOCKADDR(struct sockaddr_llc *, uaddr, msg->msg_name);
763 	const int nonblock = flags & MSG_DONTWAIT;
764 	struct sk_buff *skb = NULL;
765 	struct sock *sk = sock->sk;
766 	struct llc_sock *llc = llc_sk(sk);
767 	size_t copied = 0;
768 	u32 peek_seq = 0;
769 	u32 *seq, skb_len;
770 	unsigned long used;
771 	int target;	/* Read at least this many bytes */
772 	long timeo;
773 
774 	lock_sock(sk);
775 	copied = -ENOTCONN;
776 	if (unlikely(sk->sk_type == SOCK_STREAM && sk->sk_state == TCP_LISTEN))
777 		goto out;
778 
779 	timeo = sock_rcvtimeo(sk, nonblock);
780 
781 	seq = &llc->copied_seq;
782 	if (flags & MSG_PEEK) {
783 		peek_seq = llc->copied_seq;
784 		seq = &peek_seq;
785 	}
786 
787 	target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
788 	copied = 0;
789 
790 	do {
791 		u32 offset;
792 
793 		/*
794 		 * We need to check signals first, to get correct SIGURG
795 		 * handling. FIXME: Need to check this doesn't impact 1003.1g
796 		 * and move it down to the bottom of the loop
797 		 */
798 		if (signal_pending(current)) {
799 			if (copied)
800 				break;
801 			copied = timeo ? sock_intr_errno(timeo) : -EAGAIN;
802 			break;
803 		}
804 
805 		/* Next get a buffer. */
806 
807 		skb = skb_peek(&sk->sk_receive_queue);
808 		if (skb) {
809 			offset = *seq;
810 			goto found_ok_skb;
811 		}
812 		/* Well, if we have backlog, try to process it now yet. */
813 
814 		if (copied >= target && !READ_ONCE(sk->sk_backlog.tail))
815 			break;
816 
817 		if (copied) {
818 			if (sk->sk_err ||
819 			    sk->sk_state == TCP_CLOSE ||
820 			    (sk->sk_shutdown & RCV_SHUTDOWN) ||
821 			    !timeo ||
822 			    (flags & MSG_PEEK))
823 				break;
824 		} else {
825 			if (sock_flag(sk, SOCK_DONE))
826 				break;
827 
828 			if (sk->sk_err) {
829 				copied = sock_error(sk);
830 				break;
831 			}
832 			if (sk->sk_shutdown & RCV_SHUTDOWN)
833 				break;
834 
835 			if (sk->sk_type == SOCK_STREAM && sk->sk_state == TCP_CLOSE) {
836 				if (!sock_flag(sk, SOCK_DONE)) {
837 					/*
838 					 * This occurs when user tries to read
839 					 * from never connected socket.
840 					 */
841 					copied = -ENOTCONN;
842 					break;
843 				}
844 				break;
845 			}
846 			if (!timeo) {
847 				copied = -EAGAIN;
848 				break;
849 			}
850 		}
851 
852 		if (copied >= target) { /* Do not sleep, just process backlog. */
853 			release_sock(sk);
854 			lock_sock(sk);
855 		} else
856 			sk_wait_data(sk, &timeo, NULL);
857 
858 		if ((flags & MSG_PEEK) && peek_seq != llc->copied_seq) {
859 			net_dbg_ratelimited("LLC(%s:%d): Application bug, race in MSG_PEEK\n",
860 					    current->comm,
861 					    task_pid_nr(current));
862 			peek_seq = llc->copied_seq;
863 		}
864 		continue;
865 	found_ok_skb:
866 		skb_len = skb->len;
867 		/* Ok so how much can we use? */
868 		used = skb->len - offset;
869 		if (len < used)
870 			used = len;
871 
872 		if (!(flags & MSG_TRUNC)) {
873 			int rc = skb_copy_datagram_msg(skb, offset, msg, used);
874 			if (rc) {
875 				/* Exception. Bailout! */
876 				if (!copied)
877 					copied = -EFAULT;
878 				break;
879 			}
880 		}
881 
882 		*seq += used;
883 		copied += used;
884 		len -= used;
885 
886 		/* For non stream protcols we get one packet per recvmsg call */
887 		if (sk->sk_type != SOCK_STREAM)
888 			goto copy_uaddr;
889 
890 		if (!(flags & MSG_PEEK)) {
891 			skb_unlink(skb, &sk->sk_receive_queue);
892 			kfree_skb(skb);
893 			*seq = 0;
894 		}
895 
896 		/* Partial read */
897 		if (used + offset < skb_len)
898 			continue;
899 	} while (len > 0);
900 
901 out:
902 	release_sock(sk);
903 	return copied;
904 copy_uaddr:
905 	if (uaddr != NULL && skb != NULL) {
906 		memcpy(uaddr, llc_ui_skb_cb(skb), sizeof(*uaddr));
907 		msg->msg_namelen = sizeof(*uaddr);
908 	}
909 	if (llc_sk(sk)->cmsg_flags)
910 		llc_cmsg_rcv(msg, skb);
911 
912 	if (!(flags & MSG_PEEK)) {
913 		skb_unlink(skb, &sk->sk_receive_queue);
914 		kfree_skb(skb);
915 		*seq = 0;
916 	}
917 
918 	goto out;
919 }
920 
921 /**
922  *	llc_ui_sendmsg - Transmit data provided by the socket user.
923  *	@sock: Socket to transmit data from.
924  *	@msg: Various user related information.
925  *	@len: Length of data to transmit.
926  *
927  *	Transmit data provided by the socket user.
928  *	Returns non-negative upon success, negative otherwise.
929  */
llc_ui_sendmsg(struct socket * sock,struct msghdr * msg,size_t len)930 static int llc_ui_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
931 {
932 	DECLARE_SOCKADDR(struct sockaddr_llc *, addr, msg->msg_name);
933 	struct sock *sk = sock->sk;
934 	struct llc_sock *llc = llc_sk(sk);
935 	int flags = msg->msg_flags;
936 	int noblock = flags & MSG_DONTWAIT;
937 	int rc = -EINVAL, copied = 0, hdrlen, hh_len;
938 	struct sk_buff *skb = NULL;
939 	struct net_device *dev;
940 	size_t size = 0;
941 
942 	dprintk("%s: sending from %02X to %02X\n", __func__,
943 		llc->laddr.lsap, llc->daddr.lsap);
944 	lock_sock(sk);
945 	if (addr) {
946 		if (msg->msg_namelen < sizeof(*addr))
947 			goto out;
948 	} else {
949 		if (llc_ui_addr_null(&llc->addr))
950 			goto out;
951 		addr = &llc->addr;
952 	}
953 	/* must bind connection to sap if user hasn't done it. */
954 	if (sock_flag(sk, SOCK_ZAPPED)) {
955 		/* bind to sap with null dev, exclusive. */
956 		rc = llc_ui_autobind(sock, addr);
957 		if (rc)
958 			goto out;
959 	}
960 	dev = llc->dev;
961 	hh_len = LL_RESERVED_SPACE(dev);
962 	hdrlen = llc_ui_header_len(sk, addr);
963 	size = hdrlen + len;
964 	size = min_t(size_t, size, READ_ONCE(dev->mtu));
965 	copied = size - hdrlen;
966 	rc = -EINVAL;
967 	if (copied < 0)
968 		goto out;
969 	release_sock(sk);
970 	skb = sock_alloc_send_skb(sk, hh_len + size, noblock, &rc);
971 	lock_sock(sk);
972 	if (!skb)
973 		goto out;
974 	if (sock_flag(sk, SOCK_ZAPPED) ||
975 	    llc->dev != dev ||
976 	    hdrlen != llc_ui_header_len(sk, addr) ||
977 	    hh_len != LL_RESERVED_SPACE(dev) ||
978 	    size > READ_ONCE(dev->mtu))
979 		goto out;
980 	skb->dev      = dev;
981 	skb->protocol = llc_proto_type(addr->sllc_arphrd);
982 	skb_reserve(skb, hh_len + hdrlen);
983 	rc = memcpy_from_msg(skb_put(skb, copied), msg, copied);
984 	if (rc)
985 		goto out;
986 	if (sk->sk_type == SOCK_DGRAM || addr->sllc_ua) {
987 		llc_build_and_send_ui_pkt(llc->sap, skb, addr->sllc_mac,
988 					  addr->sllc_sap);
989 		skb = NULL;
990 		goto out;
991 	}
992 	if (addr->sllc_test) {
993 		llc_build_and_send_test_pkt(llc->sap, skb, addr->sllc_mac,
994 					    addr->sllc_sap);
995 		skb = NULL;
996 		goto out;
997 	}
998 	if (addr->sllc_xid) {
999 		llc_build_and_send_xid_pkt(llc->sap, skb, addr->sllc_mac,
1000 					   addr->sllc_sap);
1001 		skb = NULL;
1002 		goto out;
1003 	}
1004 	rc = -ENOPROTOOPT;
1005 	if (!(sk->sk_type == SOCK_STREAM && !addr->sllc_ua))
1006 		goto out;
1007 	rc = llc_ui_send_data(sk, skb, noblock);
1008 	skb = NULL;
1009 out:
1010 	kfree_skb(skb);
1011 	if (rc)
1012 		dprintk("%s: failed sending from %02X to %02X: %d\n",
1013 			__func__, llc->laddr.lsap, llc->daddr.lsap, rc);
1014 	release_sock(sk);
1015 	return rc ? : copied;
1016 }
1017 
1018 /**
1019  *	llc_ui_getname - return the address info of a socket
1020  *	@sock: Socket to get address of.
1021  *	@uaddr: Address structure to return information.
1022  *	@peer: Does user want local or remote address information.
1023  *
1024  *	Return the address information of a socket.
1025  */
llc_ui_getname(struct socket * sock,struct sockaddr * uaddr,int peer)1026 static int llc_ui_getname(struct socket *sock, struct sockaddr *uaddr,
1027 			  int peer)
1028 {
1029 	struct sockaddr_llc sllc;
1030 	struct sock *sk = sock->sk;
1031 	struct llc_sock *llc = llc_sk(sk);
1032 	int rc = -EBADF;
1033 
1034 	memset(&sllc, 0, sizeof(sllc));
1035 	lock_sock(sk);
1036 	if (sock_flag(sk, SOCK_ZAPPED))
1037 		goto out;
1038 	if (peer) {
1039 		rc = -ENOTCONN;
1040 		if (sk->sk_state != TCP_ESTABLISHED)
1041 			goto out;
1042 		if(llc->dev)
1043 			sllc.sllc_arphrd = llc->dev->type;
1044 		sllc.sllc_sap = llc->daddr.lsap;
1045 		memcpy(&sllc.sllc_mac, &llc->daddr.mac, IFHWADDRLEN);
1046 	} else {
1047 		rc = -EINVAL;
1048 		if (!llc->sap)
1049 			goto out;
1050 		sllc.sllc_sap = llc->sap->laddr.lsap;
1051 
1052 		if (llc->dev) {
1053 			sllc.sllc_arphrd = llc->dev->type;
1054 			memcpy(&sllc.sllc_mac, llc->dev->dev_addr,
1055 			       IFHWADDRLEN);
1056 		}
1057 	}
1058 	sllc.sllc_family = AF_LLC;
1059 	memcpy(uaddr, &sllc, sizeof(sllc));
1060 	rc = sizeof(sllc);
1061 out:
1062 	release_sock(sk);
1063 	return rc;
1064 }
1065 
1066 /**
1067  *	llc_ui_ioctl - io controls for PF_LLC
1068  *	@sock: Socket to get/set info
1069  *	@cmd: command
1070  *	@arg: optional argument for cmd
1071  *
1072  *	get/set info on llc sockets
1073  */
llc_ui_ioctl(struct socket * sock,unsigned int cmd,unsigned long arg)1074 static int llc_ui_ioctl(struct socket *sock, unsigned int cmd,
1075 			unsigned long arg)
1076 {
1077 	return -ENOIOCTLCMD;
1078 }
1079 
1080 /**
1081  *	llc_ui_setsockopt - set various connection specific parameters.
1082  *	@sock: Socket to set options on.
1083  *	@level: Socket level user is requesting operations on.
1084  *	@optname: Operation name.
1085  *	@optval: User provided operation data.
1086  *	@optlen: Length of optval.
1087  *
1088  *	Set various connection specific parameters.
1089  */
llc_ui_setsockopt(struct socket * sock,int level,int optname,sockptr_t optval,unsigned int optlen)1090 static int llc_ui_setsockopt(struct socket *sock, int level, int optname,
1091 			     sockptr_t optval, unsigned int optlen)
1092 {
1093 	struct sock *sk = sock->sk;
1094 	struct llc_sock *llc = llc_sk(sk);
1095 	unsigned int opt;
1096 	int rc = -EINVAL;
1097 
1098 	lock_sock(sk);
1099 	if (unlikely(level != SOL_LLC || optlen != sizeof(int)))
1100 		goto out;
1101 	rc = copy_safe_from_sockptr(&opt, sizeof(opt), optval, optlen);
1102 	if (rc)
1103 		goto out;
1104 	rc = -EINVAL;
1105 	switch (optname) {
1106 	case LLC_OPT_RETRY:
1107 		if (opt > LLC_OPT_MAX_RETRY)
1108 			goto out;
1109 		llc->n2 = opt;
1110 		break;
1111 	case LLC_OPT_SIZE:
1112 		if (opt > LLC_OPT_MAX_SIZE)
1113 			goto out;
1114 		llc->n1 = opt;
1115 		break;
1116 	case LLC_OPT_ACK_TMR_EXP:
1117 		if (opt > LLC_OPT_MAX_ACK_TMR_EXP)
1118 			goto out;
1119 		llc->ack_timer.expire = opt * HZ;
1120 		break;
1121 	case LLC_OPT_P_TMR_EXP:
1122 		if (opt > LLC_OPT_MAX_P_TMR_EXP)
1123 			goto out;
1124 		llc->pf_cycle_timer.expire = opt * HZ;
1125 		break;
1126 	case LLC_OPT_REJ_TMR_EXP:
1127 		if (opt > LLC_OPT_MAX_REJ_TMR_EXP)
1128 			goto out;
1129 		llc->rej_sent_timer.expire = opt * HZ;
1130 		break;
1131 	case LLC_OPT_BUSY_TMR_EXP:
1132 		if (opt > LLC_OPT_MAX_BUSY_TMR_EXP)
1133 			goto out;
1134 		llc->busy_state_timer.expire = opt * HZ;
1135 		break;
1136 	case LLC_OPT_TX_WIN:
1137 		if (opt > LLC_OPT_MAX_WIN)
1138 			goto out;
1139 		llc->k = opt;
1140 		break;
1141 	case LLC_OPT_RX_WIN:
1142 		if (opt > LLC_OPT_MAX_WIN)
1143 			goto out;
1144 		llc->rw = opt;
1145 		break;
1146 	case LLC_OPT_PKTINFO:
1147 		if (opt)
1148 			llc->cmsg_flags |= LLC_CMSG_PKTINFO;
1149 		else
1150 			llc->cmsg_flags &= ~LLC_CMSG_PKTINFO;
1151 		break;
1152 	default:
1153 		rc = -ENOPROTOOPT;
1154 		goto out;
1155 	}
1156 	rc = 0;
1157 out:
1158 	release_sock(sk);
1159 	return rc;
1160 }
1161 
1162 /**
1163  *	llc_ui_getsockopt - get connection specific socket info
1164  *	@sock: Socket to get information from.
1165  *	@level: Socket level user is requesting operations on.
1166  *	@optname: Operation name.
1167  *	@optval: Variable to return operation data in.
1168  *	@optlen: Length of optval.
1169  *
1170  *	Get connection specific socket information.
1171  */
llc_ui_getsockopt(struct socket * sock,int level,int optname,char __user * optval,int __user * optlen)1172 static int llc_ui_getsockopt(struct socket *sock, int level, int optname,
1173 			     char __user *optval, int __user *optlen)
1174 {
1175 	struct sock *sk = sock->sk;
1176 	struct llc_sock *llc = llc_sk(sk);
1177 	int val = 0, len = 0, rc = -EINVAL;
1178 
1179 	lock_sock(sk);
1180 	if (unlikely(level != SOL_LLC))
1181 		goto out;
1182 	rc = get_user(len, optlen);
1183 	if (rc)
1184 		goto out;
1185 	rc = -EINVAL;
1186 	if (len != sizeof(int))
1187 		goto out;
1188 	switch (optname) {
1189 	case LLC_OPT_RETRY:
1190 		val = llc->n2;					break;
1191 	case LLC_OPT_SIZE:
1192 		val = llc->n1;					break;
1193 	case LLC_OPT_ACK_TMR_EXP:
1194 		val = llc->ack_timer.expire / HZ;		break;
1195 	case LLC_OPT_P_TMR_EXP:
1196 		val = llc->pf_cycle_timer.expire / HZ;		break;
1197 	case LLC_OPT_REJ_TMR_EXP:
1198 		val = llc->rej_sent_timer.expire / HZ;		break;
1199 	case LLC_OPT_BUSY_TMR_EXP:
1200 		val = llc->busy_state_timer.expire / HZ;	break;
1201 	case LLC_OPT_TX_WIN:
1202 		val = llc->k;				break;
1203 	case LLC_OPT_RX_WIN:
1204 		val = llc->rw;				break;
1205 	case LLC_OPT_PKTINFO:
1206 		val = (llc->cmsg_flags & LLC_CMSG_PKTINFO) != 0;
1207 		break;
1208 	default:
1209 		rc = -ENOPROTOOPT;
1210 		goto out;
1211 	}
1212 	rc = 0;
1213 	if (put_user(len, optlen) || copy_to_user(optval, &val, len))
1214 		rc = -EFAULT;
1215 out:
1216 	release_sock(sk);
1217 	return rc;
1218 }
1219 
1220 static const struct net_proto_family llc_ui_family_ops = {
1221 	.family = PF_LLC,
1222 	.create = llc_ui_create,
1223 	.owner	= THIS_MODULE,
1224 };
1225 
1226 static const struct proto_ops llc_ui_ops = {
1227 	.family	     = PF_LLC,
1228 	.owner       = THIS_MODULE,
1229 	.release     = llc_ui_release,
1230 	.bind	     = llc_ui_bind,
1231 	.connect     = llc_ui_connect,
1232 	.socketpair  = sock_no_socketpair,
1233 	.accept      = llc_ui_accept,
1234 	.getname     = llc_ui_getname,
1235 	.poll	     = datagram_poll,
1236 	.ioctl       = llc_ui_ioctl,
1237 	.listen      = llc_ui_listen,
1238 	.shutdown    = llc_ui_shutdown,
1239 	.setsockopt  = llc_ui_setsockopt,
1240 	.getsockopt  = llc_ui_getsockopt,
1241 	.sendmsg     = llc_ui_sendmsg,
1242 	.recvmsg     = llc_ui_recvmsg,
1243 	.mmap	     = sock_no_mmap,
1244 };
1245 
1246 static const char llc_proc_err_msg[] __initconst =
1247 	KERN_CRIT "LLC: Unable to register the proc_fs entries\n";
1248 static const char llc_sysctl_err_msg[] __initconst =
1249 	KERN_CRIT "LLC: Unable to register the sysctl entries\n";
1250 static const char llc_sock_err_msg[] __initconst =
1251 	KERN_CRIT "LLC: Unable to register the network family\n";
1252 
llc2_init(void)1253 static int __init llc2_init(void)
1254 {
1255 	int rc = proto_register(&llc_proto, 0);
1256 
1257 	if (rc != 0)
1258 		goto out;
1259 
1260 	llc_build_offset_table();
1261 	llc_station_init();
1262 	llc_ui_sap_last_autoport = LLC_SAP_DYN_START;
1263 	rc = llc_proc_init();
1264 	if (rc != 0) {
1265 		printk(llc_proc_err_msg);
1266 		goto out_station;
1267 	}
1268 	rc = llc_sysctl_init();
1269 	if (rc) {
1270 		printk(llc_sysctl_err_msg);
1271 		goto out_proc;
1272 	}
1273 	rc = sock_register(&llc_ui_family_ops);
1274 	if (rc) {
1275 		printk(llc_sock_err_msg);
1276 		goto out_sysctl;
1277 	}
1278 	llc_add_pack(LLC_DEST_SAP, llc_sap_handler);
1279 	llc_add_pack(LLC_DEST_CONN, llc_conn_handler);
1280 out:
1281 	return rc;
1282 out_sysctl:
1283 	llc_sysctl_exit();
1284 out_proc:
1285 	llc_proc_exit();
1286 out_station:
1287 	llc_station_exit();
1288 	proto_unregister(&llc_proto);
1289 	goto out;
1290 }
1291 
llc2_exit(void)1292 static void __exit llc2_exit(void)
1293 {
1294 	llc_station_exit();
1295 	llc_remove_pack(LLC_DEST_SAP);
1296 	llc_remove_pack(LLC_DEST_CONN);
1297 	sock_unregister(PF_LLC);
1298 	llc_proc_exit();
1299 	llc_sysctl_exit();
1300 	proto_unregister(&llc_proto);
1301 }
1302 
1303 module_init(llc2_init);
1304 module_exit(llc2_exit);
1305 
1306 MODULE_LICENSE("GPL");
1307 MODULE_AUTHOR("Procom 1997, Jay Schullist 2001, Arnaldo C. Melo 2001-2003");
1308 MODULE_DESCRIPTION("IEEE 802.2 PF_LLC support");
1309 MODULE_ALIAS_NETPROTO(PF_LLC);
1310