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Linux 4.1.16
[linux/fpc-iii.git] / net / llc / af_llc.c
blob17a8dff0609066e338b528328c4ed01259314d43
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 <net/llc.h>
30 #include <net/llc_sap.h>
31 #include <net/llc_pdu.h>
32 #include <net/llc_conn.h>
33 #include <net/tcp_states.h>
34
35 /* remember: uninitialized global data is zeroed because its in .bss */
36 static u16 llc_ui_sap_last_autoport = LLC_SAP_DYN_START;
37 static u16 llc_ui_sap_link_no_max[256];
38 static struct sockaddr_llc llc_ui_addrnull;
39 static const struct proto_ops llc_ui_ops;
40
41 static int llc_ui_wait_for_conn(struct sock *sk, long timeout);
42 static int llc_ui_wait_for_disc(struct sock *sk, long timeout);
43 static int llc_ui_wait_for_busy_core(struct sock *sk, long timeout);
44
45 #if 0
46 #define dprintk(args...) printk(KERN_DEBUG args)
47 #else
48 #define dprintk(args...)
49 #endif
50
51 /* Maybe we'll add some more in the future. */
52 #define LLC_CMSG_PKTINFO 1
53
54
55 /**
56 * llc_ui_next_link_no - return the next unused link number for a sap
57 * @sap: Address of sap to get link number from.
58 *
59 * Return the next unused link number for a given sap.
60 */
61 static inline u16 llc_ui_next_link_no(int sap)
62 {
63 return llc_ui_sap_link_no_max[sap]++;
64 }
65
66 /**
67 * llc_proto_type - return eth protocol for ARP header type
68 * @arphrd: ARP header type.
69 *
70 * Given an ARP header type return the corresponding ethernet protocol.
71 */
72 static inline __be16 llc_proto_type(u16 arphrd)
73 {
74 return htons(ETH_P_802_2);
75 }
76
77 /**
78 * llc_ui_addr_null - determines if a address structure is null
79 * @addr: Address to test if null.
80 */
81 static inline u8 llc_ui_addr_null(struct sockaddr_llc *addr)
82 {
83 return !memcmp(addr, &llc_ui_addrnull, sizeof(*addr));
84 }
85
86 /**
87 * llc_ui_header_len - return length of llc header based on operation
88 * @sk: Socket which contains a valid llc socket type.
89 * @addr: Complete sockaddr_llc structure received from the user.
90 *
91 * Provide the length of the llc header depending on what kind of
92 * operation the user would like to perform and the type of socket.
93 * Returns the correct llc header length.
94 */
95 static inline u8 llc_ui_header_len(struct sock *sk, struct sockaddr_llc *addr)
96 {
97 u8 rc = LLC_PDU_LEN_U;
98
99 if (addr->sllc_test || addr->sllc_xid)
100 rc = LLC_PDU_LEN_U;
101 else if (sk->sk_type == SOCK_STREAM)
102 rc = LLC_PDU_LEN_I;
103 return rc;
104 }
105
106 /**
107 * llc_ui_send_data - send data via reliable llc2 connection
108 * @sk: Connection the socket is using.
109 * @skb: Data the user wishes to send.
110 * @noblock: can we block waiting for data?
111 *
112 * Send data via reliable llc2 connection.
113 * Returns 0 upon success, non-zero if action did not succeed.
114 */
115 static int llc_ui_send_data(struct sock* sk, struct sk_buff *skb, int noblock)
116 {
117 struct llc_sock* llc = llc_sk(sk);
118 int rc = 0;
119
120 if (unlikely(llc_data_accept_state(llc->state) ||
121 llc->remote_busy_flag ||
122 llc->p_flag)) {
123 long timeout = sock_sndtimeo(sk, noblock);
124
125 rc = llc_ui_wait_for_busy_core(sk, timeout);
126 }
127 if (unlikely(!rc))
128 rc = llc_build_and_send_pkt(sk, skb);
129 return rc;
130 }
131
132 static void llc_ui_sk_init(struct socket *sock, struct sock *sk)
133 {
134 sock_graft(sk, sock);
135 sk->sk_type = sock->type;
136 sock->ops = &llc_ui_ops;
137 }
138
139 static struct proto llc_proto = {
140 .name = "LLC",
141 .owner = THIS_MODULE,
142 .obj_size = sizeof(struct llc_sock),
143 .slab_flags = SLAB_DESTROY_BY_RCU,
144 };
145
146 /**
147 * llc_ui_create - alloc and init a new llc_ui socket
148 * @net: network namespace (must be default network)
149 * @sock: Socket to initialize and attach allocated sk to.
150 * @protocol: Unused.
151 * @kern: on behalf of kernel or userspace
152 *
153 * Allocate and initialize a new llc_ui socket, validate the user wants a
154 * socket type we have available.
155 * Returns 0 upon success, negative upon failure.
156 */
157 static int llc_ui_create(struct net *net, struct socket *sock, int protocol,
158 int kern)
159 {
160 struct sock *sk;
161 int rc = -ESOCKTNOSUPPORT;
162
163 if (!ns_capable(net->user_ns, CAP_NET_RAW))
164 return -EPERM;
165
166 if (!net_eq(net, &init_net))
167 return -EAFNOSUPPORT;
168
169 if (likely(sock->type == SOCK_DGRAM || sock->type == SOCK_STREAM)) {
170 rc = -ENOMEM;
171 sk = llc_sk_alloc(net, PF_LLC, GFP_KERNEL, &llc_proto);
172 if (sk) {
173 rc = 0;
174 llc_ui_sk_init(sock, sk);
175 }
176 }
177 return rc;
178 }
179
180 /**
181 * llc_ui_release - shutdown socket
182 * @sock: Socket to release.
183 *
184 * Shutdown and deallocate an existing socket.
185 */
186 static int llc_ui_release(struct socket *sock)
187 {
188 struct sock *sk = sock->sk;
189 struct llc_sock *llc;
190
191 if (unlikely(sk == NULL))
192 goto out;
193 sock_hold(sk);
194 lock_sock(sk);
195 llc = llc_sk(sk);
196 dprintk("%s: closing local(%02X) remote(%02X)\n", __func__,
197 llc->laddr.lsap, llc->daddr.lsap);
198 if (!llc_send_disc(sk))
199 llc_ui_wait_for_disc(sk, sk->sk_rcvtimeo);
200 if (!sock_flag(sk, SOCK_ZAPPED))
201 llc_sap_remove_socket(llc->sap, sk);
202 release_sock(sk);
203 if (llc->dev)
204 dev_put(llc->dev);
205 sock_put(sk);
206 llc_sk_free(sk);
207 out:
208 return 0;
209 }
210
211 /**
212 * llc_ui_autoport - provide dynamically allocate SAP number
213 *
214 * Provide the caller with a dynamically allocated SAP number according
215 * to the rules that are set in this function. Returns: 0, upon failure,
216 * SAP number otherwise.
217 */
218 static int llc_ui_autoport(void)
219 {
220 struct llc_sap *sap;
221 int i, tries = 0;
222
223 while (tries < LLC_SAP_DYN_TRIES) {
224 for (i = llc_ui_sap_last_autoport;
225 i < LLC_SAP_DYN_STOP; i += 2) {
226 sap = llc_sap_find(i);
227 if (!sap) {
228 llc_ui_sap_last_autoport = i + 2;
229 goto out;
230 }
231 llc_sap_put(sap);
232 }
233 llc_ui_sap_last_autoport = LLC_SAP_DYN_START;
234 tries++;
235 }
236 i = 0;
237 out:
238 return i;
239 }
240
241 /**
242 * llc_ui_autobind - automatically bind a socket to a sap
243 * @sock: socket to bind
244 * @addr: address to connect to
245 *
246 * Used by llc_ui_connect and llc_ui_sendmsg when the user hasn't
247 * specifically used llc_ui_bind to bind to an specific address/sap
248 *
249 * Returns: 0 upon success, negative otherwise.
250 */
251 static int llc_ui_autobind(struct socket *sock, struct sockaddr_llc *addr)
252 {
253 struct sock *sk = sock->sk;
254 struct llc_sock *llc = llc_sk(sk);
255 struct llc_sap *sap;
256 int rc = -EINVAL;
257
258 if (!sock_flag(sk, SOCK_ZAPPED))
259 goto out;
260 rc = -ENODEV;
261 if (sk->sk_bound_dev_if) {
262 llc->dev = dev_get_by_index(&init_net, sk->sk_bound_dev_if);
263 if (llc->dev && addr->sllc_arphrd != llc->dev->type) {
264 dev_put(llc->dev);
265 llc->dev = NULL;
266 }
267 } else
268 llc->dev = dev_getfirstbyhwtype(&init_net, addr->sllc_arphrd);
269 if (!llc->dev)
270 goto out;
271 rc = -EUSERS;
272 llc->laddr.lsap = llc_ui_autoport();
273 if (!llc->laddr.lsap)
274 goto out;
275 rc = -EBUSY; /* some other network layer is using the sap */
276 sap = llc_sap_open(llc->laddr.lsap, NULL);
277 if (!sap)
278 goto out;
279 memcpy(llc->laddr.mac, llc->dev->dev_addr, IFHWADDRLEN);
280 memcpy(&llc->addr, addr, sizeof(llc->addr));
281 /* assign new connection to its SAP */
282 llc_sap_add_socket(sap, sk);
283 sock_reset_flag(sk, SOCK_ZAPPED);
284 rc = 0;
285 out:
286 return rc;
287 }
288
289 /**
290 * llc_ui_bind - bind a socket to a specific address.
291 * @sock: Socket to bind an address to.
292 * @uaddr: Address the user wants the socket bound to.
293 * @addrlen: Length of the uaddr structure.
294 *
295 * Bind a socket to a specific address. For llc a user is able to bind to
296 * a specific sap only or mac + sap.
297 * If the user desires to bind to a specific mac + sap, it is possible to
298 * have multiple sap connections via multiple macs.
299 * Bind and autobind for that matter must enforce the correct sap usage
300 * otherwise all hell will break loose.
301 * Returns: 0 upon success, negative otherwise.
302 */
303 static int llc_ui_bind(struct socket *sock, struct sockaddr *uaddr, int addrlen)
304 {
305 struct sockaddr_llc *addr = (struct sockaddr_llc *)uaddr;
306 struct sock *sk = sock->sk;
307 struct llc_sock *llc = llc_sk(sk);
308 struct llc_sap *sap;
309 int rc = -EINVAL;
310
311 dprintk("%s: binding %02X\n", __func__, addr->sllc_sap);
312 if (unlikely(!sock_flag(sk, SOCK_ZAPPED) || addrlen != sizeof(*addr)))
313 goto out;
314 rc = -EAFNOSUPPORT;
315 if (unlikely(addr->sllc_family != AF_LLC))
316 goto out;
317 rc = -ENODEV;
318 rcu_read_lock();
319 if (sk->sk_bound_dev_if) {
320 llc->dev = dev_get_by_index_rcu(&init_net, sk->sk_bound_dev_if);
321 if (llc->dev) {
322 if (!addr->sllc_arphrd)
323 addr->sllc_arphrd = llc->dev->type;
324 if (is_zero_ether_addr(addr->sllc_mac))
325 memcpy(addr->sllc_mac, llc->dev->dev_addr,
326 IFHWADDRLEN);
327 if (addr->sllc_arphrd != llc->dev->type ||
328 !ether_addr_equal(addr->sllc_mac,
329 llc->dev->dev_addr)) {
330 rc = -EINVAL;
331 llc->dev = NULL;
332 }
333 }
334 } else
335 llc->dev = dev_getbyhwaddr_rcu(&init_net, addr->sllc_arphrd,
336 addr->sllc_mac);
337 if (llc->dev)
338 dev_hold(llc->dev);
339 rcu_read_unlock();
340 if (!llc->dev)
341 goto out;
342 if (!addr->sllc_sap) {
343 rc = -EUSERS;
344 addr->sllc_sap = llc_ui_autoport();
345 if (!addr->sllc_sap)
346 goto out;
347 }
348 sap = llc_sap_find(addr->sllc_sap);
349 if (!sap) {
350 sap = llc_sap_open(addr->sllc_sap, NULL);
351 rc = -EBUSY; /* some other network layer is using the sap */
352 if (!sap)
353 goto out;
354 } else {
355 struct llc_addr laddr, daddr;
356 struct sock *ask;
357
358 memset(&laddr, 0, sizeof(laddr));
359 memset(&daddr, 0, sizeof(daddr));
360 /*
361 * FIXME: check if the address is multicast,
362 * only SOCK_DGRAM can do this.
363 */
364 memcpy(laddr.mac, addr->sllc_mac, IFHWADDRLEN);
365 laddr.lsap = addr->sllc_sap;
366 rc = -EADDRINUSE; /* mac + sap clash. */
367 ask = llc_lookup_established(sap, &daddr, &laddr);
368 if (ask) {
369 sock_put(ask);
370 goto out_put;
371 }
372 }
373 llc->laddr.lsap = addr->sllc_sap;
374 memcpy(llc->laddr.mac, addr->sllc_mac, IFHWADDRLEN);
375 memcpy(&llc->addr, addr, sizeof(llc->addr));
376 /* assign new connection to its SAP */
377 llc_sap_add_socket(sap, sk);
378 sock_reset_flag(sk, SOCK_ZAPPED);
379 rc = 0;
380 out_put:
381 llc_sap_put(sap);
382 out:
383 return rc;
384 }
385
386 /**
387 * llc_ui_shutdown - shutdown a connect llc2 socket.
388 * @sock: Socket to shutdown.
389 * @how: What part of the socket to shutdown.
390 *
391 * Shutdown a connected llc2 socket. Currently this function only supports
392 * shutting down both sends and receives (2), we could probably make this
393 * function such that a user can shutdown only half the connection but not
394 * right now.
395 * Returns: 0 upon success, negative otherwise.
396 */
397 static int llc_ui_shutdown(struct socket *sock, int how)
398 {
399 struct sock *sk = sock->sk;
400 int rc = -ENOTCONN;
401
402 lock_sock(sk);
403 if (unlikely(sk->sk_state != TCP_ESTABLISHED))
404 goto out;
405 rc = -EINVAL;
406 if (how != 2)
407 goto out;
408 rc = llc_send_disc(sk);
409 if (!rc)
410 rc = llc_ui_wait_for_disc(sk, sk->sk_rcvtimeo);
411 /* Wake up anyone sleeping in poll */
412 sk->sk_state_change(sk);
413 out:
414 release_sock(sk);
415 return rc;
416 }
417
418 /**
419 * llc_ui_connect - Connect to a remote llc2 mac + sap.
420 * @sock: Socket which will be connected to the remote destination.
421 * @uaddr: Remote and possibly the local address of the new connection.
422 * @addrlen: Size of uaddr structure.
423 * @flags: Operational flags specified by the user.
424 *
425 * Connect to a remote llc2 mac + sap. The caller must specify the
426 * destination mac and address to connect to. If the user hasn't previously
427 * called bind(2) with a smac the address of the first interface of the
428 * specified arp type will be used.
429 * This function will autobind if user did not previously call bind.
430 * Returns: 0 upon success, negative otherwise.
431 */
432 static int llc_ui_connect(struct socket *sock, struct sockaddr *uaddr,
433 int addrlen, int flags)
434 {
435 struct sock *sk = sock->sk;
436 struct llc_sock *llc = llc_sk(sk);
437 struct sockaddr_llc *addr = (struct sockaddr_llc *)uaddr;
438 int rc = -EINVAL;
439
440 lock_sock(sk);
441 if (unlikely(addrlen != sizeof(*addr)))
442 goto out;
443 rc = -EAFNOSUPPORT;
444 if (unlikely(addr->sllc_family != AF_LLC))
445 goto out;
446 if (unlikely(sk->sk_type != SOCK_STREAM))
447 goto out;
448 rc = -EALREADY;
449 if (unlikely(sock->state == SS_CONNECTING))
450 goto out;
451 /* bind connection to sap if user hasn't done it. */
452 if (sock_flag(sk, SOCK_ZAPPED)) {
453 /* bind to sap with null dev, exclusive */
454 rc = llc_ui_autobind(sock, addr);
455 if (rc)
456 goto out;
457 }
458 llc->daddr.lsap = addr->sllc_sap;
459 memcpy(llc->daddr.mac, addr->sllc_mac, IFHWADDRLEN);
460 sock->state = SS_CONNECTING;
461 sk->sk_state = TCP_SYN_SENT;
462 llc->link = llc_ui_next_link_no(llc->sap->laddr.lsap);
463 rc = llc_establish_connection(sk, llc->dev->dev_addr,
464 addr->sllc_mac, addr->sllc_sap);
465 if (rc) {
466 dprintk("%s: llc_ui_send_conn failed :-(\n", __func__);
467 sock->state = SS_UNCONNECTED;
468 sk->sk_state = TCP_CLOSE;
469 goto out;
470 }
471
472 if (sk->sk_state == TCP_SYN_SENT) {
473 const long timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
474
475 if (!timeo || !llc_ui_wait_for_conn(sk, timeo))
476 goto out;
477
478 rc = sock_intr_errno(timeo);
479 if (signal_pending(current))
480 goto out;
481 }
482
483 if (sk->sk_state == TCP_CLOSE)
484 goto sock_error;
485
486 sock->state = SS_CONNECTED;
487 rc = 0;
488 out:
489 release_sock(sk);
490 return rc;
491 sock_error:
492 rc = sock_error(sk) ? : -ECONNABORTED;
493 sock->state = SS_UNCONNECTED;
494 goto out;
495 }
496
497 /**
498 * llc_ui_listen - allow a normal socket to accept incoming connections
499 * @sock: Socket to allow incoming connections on.
500 * @backlog: Number of connections to queue.
501 *
502 * Allow a normal socket to accept incoming connections.
503 * Returns 0 upon success, negative otherwise.
504 */
505 static int llc_ui_listen(struct socket *sock, int backlog)
506 {
507 struct sock *sk = sock->sk;
508 int rc = -EINVAL;
509
510 lock_sock(sk);
511 if (unlikely(sock->state != SS_UNCONNECTED))
512 goto out;
513 rc = -EOPNOTSUPP;
514 if (unlikely(sk->sk_type != SOCK_STREAM))
515 goto out;
516 rc = -EAGAIN;
517 if (sock_flag(sk, SOCK_ZAPPED))
518 goto out;
519 rc = 0;
520 if (!(unsigned int)backlog) /* BSDism */
521 backlog = 1;
522 sk->sk_max_ack_backlog = backlog;
523 if (sk->sk_state != TCP_LISTEN) {
524 sk->sk_ack_backlog = 0;
525 sk->sk_state = TCP_LISTEN;
526 }
527 sk->sk_socket->flags |= __SO_ACCEPTCON;
528 out:
529 release_sock(sk);
530 return rc;
531 }
532
533 static int llc_ui_wait_for_disc(struct sock *sk, long timeout)
534 {
535 DEFINE_WAIT(wait);
536 int rc = 0;
537
538 while (1) {
539 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
540 if (sk_wait_event(sk, &timeout, sk->sk_state == TCP_CLOSE))
541 break;
542 rc = -ERESTARTSYS;
543 if (signal_pending(current))
544 break;
545 rc = -EAGAIN;
546 if (!timeout)
547 break;
548 rc = 0;
549 }
550 finish_wait(sk_sleep(sk), &wait);
551 return rc;
552 }
553
554 static int llc_ui_wait_for_conn(struct sock *sk, long timeout)
555 {
556 DEFINE_WAIT(wait);
557
558 while (1) {
559 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
560 if (sk_wait_event(sk, &timeout, sk->sk_state != TCP_SYN_SENT))
561 break;
562 if (signal_pending(current) || !timeout)
563 break;
564 }
565 finish_wait(sk_sleep(sk), &wait);
566 return timeout;
567 }
568
569 static int llc_ui_wait_for_busy_core(struct sock *sk, long timeout)
570 {
571 DEFINE_WAIT(wait);
572 struct llc_sock *llc = llc_sk(sk);
573 int rc;
574
575 while (1) {
576 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
577 rc = 0;
578 if (sk_wait_event(sk, &timeout,
579 (sk->sk_shutdown & RCV_SHUTDOWN) ||
580 (!llc_data_accept_state(llc->state) &&
581 !llc->remote_busy_flag &&
582 !llc->p_flag)))
583 break;
584 rc = -ERESTARTSYS;
585 if (signal_pending(current))
586 break;
587 rc = -EAGAIN;
588 if (!timeout)
589 break;
590 }
591 finish_wait(sk_sleep(sk), &wait);
592 return rc;
593 }
594
595 static int llc_wait_data(struct sock *sk, long timeo)
596 {
597 int rc;
598
599 while (1) {
600 /*
601 * POSIX 1003.1g mandates this order.
602 */
603 rc = sock_error(sk);
604 if (rc)
605 break;
606 rc = 0;
607 if (sk->sk_shutdown & RCV_SHUTDOWN)
608 break;
609 rc = -EAGAIN;
610 if (!timeo)
611 break;
612 rc = sock_intr_errno(timeo);
613 if (signal_pending(current))
614 break;
615 rc = 0;
616 if (sk_wait_data(sk, &timeo))
617 break;
618 }
619 return rc;
620 }
621
622 static void llc_cmsg_rcv(struct msghdr *msg, struct sk_buff *skb)
623 {
624 struct llc_sock *llc = llc_sk(skb->sk);
625
626 if (llc->cmsg_flags & LLC_CMSG_PKTINFO) {
627 struct llc_pktinfo info;
628
629 info.lpi_ifindex = llc_sk(skb->sk)->dev->ifindex;
630 llc_pdu_decode_dsap(skb, &info.lpi_sap);
631 llc_pdu_decode_da(skb, info.lpi_mac);
632 put_cmsg(msg, SOL_LLC, LLC_OPT_PKTINFO, sizeof(info), &info);
633 }
634 }
635
636 /**
637 * llc_ui_accept - accept a new incoming connection.
638 * @sock: Socket which connections arrive on.
639 * @newsock: Socket to move incoming connection to.
640 * @flags: User specified operational flags.
641 *
642 * Accept a new incoming connection.
643 * Returns 0 upon success, negative otherwise.
644 */
645 static int llc_ui_accept(struct socket *sock, struct socket *newsock, int flags)
646 {
647 struct sock *sk = sock->sk, *newsk;
648 struct llc_sock *llc, *newllc;
649 struct sk_buff *skb;
650 int rc = -EOPNOTSUPP;
651
652 dprintk("%s: accepting on %02X\n", __func__,
653 llc_sk(sk)->laddr.lsap);
654 lock_sock(sk);
655 if (unlikely(sk->sk_type != SOCK_STREAM))
656 goto out;
657 rc = -EINVAL;
658 if (unlikely(sock->state != SS_UNCONNECTED ||
659 sk->sk_state != TCP_LISTEN))
660 goto out;
661 /* wait for a connection to arrive. */
662 if (skb_queue_empty(&sk->sk_receive_queue)) {
663 rc = llc_wait_data(sk, sk->sk_rcvtimeo);
664 if (rc)
665 goto out;
666 }
667 dprintk("%s: got a new connection on %02X\n", __func__,
668 llc_sk(sk)->laddr.lsap);
669 skb = skb_dequeue(&sk->sk_receive_queue);
670 rc = -EINVAL;
671 if (!skb->sk)
672 goto frees;
673 rc = 0;
674 newsk = skb->sk;
675 /* attach connection to a new socket. */
676 llc_ui_sk_init(newsock, newsk);
677 sock_reset_flag(newsk, SOCK_ZAPPED);
678 newsk->sk_state = TCP_ESTABLISHED;
679 newsock->state = SS_CONNECTED;
680 llc = llc_sk(sk);
681 newllc = llc_sk(newsk);
682 memcpy(&newllc->addr, &llc->addr, sizeof(newllc->addr));
683 newllc->link = llc_ui_next_link_no(newllc->laddr.lsap);
684
685 /* put original socket back into a clean listen state. */
686 sk->sk_state = TCP_LISTEN;
687 sk->sk_ack_backlog--;
688 dprintk("%s: ok success on %02X, client on %02X\n", __func__,
689 llc_sk(sk)->addr.sllc_sap, newllc->daddr.lsap);
690 frees:
691 kfree_skb(skb);
692 out:
693 release_sock(sk);
694 return rc;
695 }
696
697 /**
698 * llc_ui_recvmsg - copy received data to the socket user.
699 * @sock: Socket to copy data from.
700 * @msg: Various user space related information.
701 * @len: Size of user buffer.
702 * @flags: User specified flags.
703 *
704 * Copy received data to the socket user.
705 * Returns non-negative upon success, negative otherwise.
706 */
707 static int llc_ui_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
708 int flags)
709 {
710 DECLARE_SOCKADDR(struct sockaddr_llc *, uaddr, msg->msg_name);
711 const int nonblock = flags & MSG_DONTWAIT;
712 struct sk_buff *skb = NULL;
713 struct sock *sk = sock->sk;
714 struct llc_sock *llc = llc_sk(sk);
715 unsigned long cpu_flags;
716 size_t copied = 0;
717 u32 peek_seq = 0;
718 u32 *seq, skb_len;
719 unsigned long used;
720 int target; /* Read at least this many bytes */
721 long timeo;
722
723 lock_sock(sk);
724 copied = -ENOTCONN;
725 if (unlikely(sk->sk_type == SOCK_STREAM && sk->sk_state == TCP_LISTEN))
726 goto out;
727
728 timeo = sock_rcvtimeo(sk, nonblock);
729
730 seq = &llc->copied_seq;
731 if (flags & MSG_PEEK) {
732 peek_seq = llc->copied_seq;
733 seq = &peek_seq;
734 }
735
736 target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
737 copied = 0;
738
739 do {
740 u32 offset;
741
742 /*
743 * We need to check signals first, to get correct SIGURG
744 * handling. FIXME: Need to check this doesn't impact 1003.1g
745 * and move it down to the bottom of the loop
746 */
747 if (signal_pending(current)) {
748 if (copied)
749 break;
750 copied = timeo ? sock_intr_errno(timeo) : -EAGAIN;
751 break;
752 }
753
754 /* Next get a buffer. */
755
756 skb = skb_peek(&sk->sk_receive_queue);
757 if (skb) {
758 offset = *seq;
759 goto found_ok_skb;
760 }
761 /* Well, if we have backlog, try to process it now yet. */
762
763 if (copied >= target && !sk->sk_backlog.tail)
764 break;
765
766 if (copied) {
767 if (sk->sk_err ||
768 sk->sk_state == TCP_CLOSE ||
769 (sk->sk_shutdown & RCV_SHUTDOWN) ||
770 !timeo ||
771 (flags & MSG_PEEK))
772 break;
773 } else {
774 if (sock_flag(sk, SOCK_DONE))
775 break;
776
777 if (sk->sk_err) {
778 copied = sock_error(sk);
779 break;
780 }
781 if (sk->sk_shutdown & RCV_SHUTDOWN)
782 break;
783
784 if (sk->sk_type == SOCK_STREAM && sk->sk_state == TCP_CLOSE) {
785 if (!sock_flag(sk, SOCK_DONE)) {
786 /*
787 * This occurs when user tries to read
788 * from never connected socket.
789 */
790 copied = -ENOTCONN;
791 break;
792 }
793 break;
794 }
795 if (!timeo) {
796 copied = -EAGAIN;
797 break;
798 }
799 }
800
801 if (copied >= target) { /* Do not sleep, just process backlog. */
802 release_sock(sk);
803 lock_sock(sk);
804 } else
805 sk_wait_data(sk, &timeo);
806
807 if ((flags & MSG_PEEK) && peek_seq != llc->copied_seq) {
808 net_dbg_ratelimited("LLC(%s:%d): Application bug, race in MSG_PEEK\n",
809 current->comm,
810 task_pid_nr(current));
811 peek_seq = llc->copied_seq;
812 }
813 continue;
814 found_ok_skb:
815 skb_len = skb->len;
816 /* Ok so how much can we use? */
817 used = skb->len - offset;
818 if (len < used)
819 used = len;
820
821 if (!(flags & MSG_TRUNC)) {
822 int rc = skb_copy_datagram_msg(skb, offset, msg, used);
823 if (rc) {
824 /* Exception. Bailout! */
825 if (!copied)
826 copied = -EFAULT;
827 break;
828 }
829 }
830
831 *seq += used;
832 copied += used;
833 len -= used;
834
835 /* For non stream protcols we get one packet per recvmsg call */
836 if (sk->sk_type != SOCK_STREAM)
837 goto copy_uaddr;
838
839 if (!(flags & MSG_PEEK)) {
840 spin_lock_irqsave(&sk->sk_receive_queue.lock, cpu_flags);
841 sk_eat_skb(sk, skb);
842 spin_unlock_irqrestore(&sk->sk_receive_queue.lock, cpu_flags);
843 *seq = 0;
844 }
845
846 /* Partial read */
847 if (used + offset < skb_len)
848 continue;
849 } while (len > 0);
850
851 out:
852 release_sock(sk);
853 return copied;
854 copy_uaddr:
855 if (uaddr != NULL && skb != NULL) {
856 memcpy(uaddr, llc_ui_skb_cb(skb), sizeof(*uaddr));
857 msg->msg_namelen = sizeof(*uaddr);
858 }
859 if (llc_sk(sk)->cmsg_flags)
860 llc_cmsg_rcv(msg, skb);
861
862 if (!(flags & MSG_PEEK)) {
863 spin_lock_irqsave(&sk->sk_receive_queue.lock, cpu_flags);
864 sk_eat_skb(sk, skb);
865 spin_unlock_irqrestore(&sk->sk_receive_queue.lock, cpu_flags);
866 *seq = 0;
867 }
868
869 goto out;
870 }
871
872 /**
873 * llc_ui_sendmsg - Transmit data provided by the socket user.
874 * @sock: Socket to transmit data from.
875 * @msg: Various user related information.
876 * @len: Length of data to transmit.
877 *
878 * Transmit data provided by the socket user.
879 * Returns non-negative upon success, negative otherwise.
880 */
881 static int llc_ui_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
882 {
883 struct sock *sk = sock->sk;
884 struct llc_sock *llc = llc_sk(sk);
885 DECLARE_SOCKADDR(struct sockaddr_llc *, addr, msg->msg_name);
886 int flags = msg->msg_flags;
887 int noblock = flags & MSG_DONTWAIT;
888 struct sk_buff *skb;
889 size_t size = 0;
890 int rc = -EINVAL, copied = 0, hdrlen;
891
892 dprintk("%s: sending from %02X to %02X\n", __func__,
893 llc->laddr.lsap, llc->daddr.lsap);
894 lock_sock(sk);
895 if (addr) {
896 if (msg->msg_namelen < sizeof(*addr))
897 goto release;
898 } else {
899 if (llc_ui_addr_null(&llc->addr))
900 goto release;
901 addr = &llc->addr;
902 }
903 /* must bind connection to sap if user hasn't done it. */
904 if (sock_flag(sk, SOCK_ZAPPED)) {
905 /* bind to sap with null dev, exclusive. */
906 rc = llc_ui_autobind(sock, addr);
907 if (rc)
908 goto release;
909 }
910 hdrlen = llc->dev->hard_header_len + llc_ui_header_len(sk, addr);
911 size = hdrlen + len;
912 if (size > llc->dev->mtu)
913 size = llc->dev->mtu;
914 copied = size - hdrlen;
915 release_sock(sk);
916 skb = sock_alloc_send_skb(sk, size, noblock, &rc);
917 lock_sock(sk);
918 if (!skb)
919 goto release;
920 skb->dev = llc->dev;
921 skb->protocol = llc_proto_type(addr->sllc_arphrd);
922 skb_reserve(skb, hdrlen);
923 rc = memcpy_from_msg(skb_put(skb, copied), msg, copied);
924 if (rc)
925 goto out;
926 if (sk->sk_type == SOCK_DGRAM || addr->sllc_ua) {
927 llc_build_and_send_ui_pkt(llc->sap, skb, addr->sllc_mac,
928 addr->sllc_sap);
929 goto out;
930 }
931 if (addr->sllc_test) {
932 llc_build_and_send_test_pkt(llc->sap, skb, addr->sllc_mac,
933 addr->sllc_sap);
934 goto out;
935 }
936 if (addr->sllc_xid) {
937 llc_build_and_send_xid_pkt(llc->sap, skb, addr->sllc_mac,
938 addr->sllc_sap);
939 goto out;
940 }
941 rc = -ENOPROTOOPT;
942 if (!(sk->sk_type == SOCK_STREAM && !addr->sllc_ua))
943 goto out;
944 rc = llc_ui_send_data(sk, skb, noblock);
945 out:
946 if (rc) {
947 kfree_skb(skb);
948 release:
949 dprintk("%s: failed sending from %02X to %02X: %d\n",
950 __func__, llc->laddr.lsap, llc->daddr.lsap, rc);
951 }
952 release_sock(sk);
953 return rc ? : copied;
954 }
955
956 /**
957 * llc_ui_getname - return the address info of a socket
958 * @sock: Socket to get address of.
959 * @uaddr: Address structure to return information.
960 * @uaddrlen: Length of address structure.
961 * @peer: Does user want local or remote address information.
962 *
963 * Return the address information of a socket.
964 */
965 static int llc_ui_getname(struct socket *sock, struct sockaddr *uaddr,
966 int *uaddrlen, int peer)
967 {
968 struct sockaddr_llc sllc;
969 struct sock *sk = sock->sk;
970 struct llc_sock *llc = llc_sk(sk);
971 int rc = -EBADF;
972
973 memset(&sllc, 0, sizeof(sllc));
974 lock_sock(sk);
975 if (sock_flag(sk, SOCK_ZAPPED))
976 goto out;
977 *uaddrlen = sizeof(sllc);
978 if (peer) {
979 rc = -ENOTCONN;
980 if (sk->sk_state != TCP_ESTABLISHED)
981 goto out;
982 if(llc->dev)
983 sllc.sllc_arphrd = llc->dev->type;
984 sllc.sllc_sap = llc->daddr.lsap;
985 memcpy(&sllc.sllc_mac, &llc->daddr.mac, IFHWADDRLEN);
986 } else {
987 rc = -EINVAL;
988 if (!llc->sap)
989 goto out;
990 sllc.sllc_sap = llc->sap->laddr.lsap;
991
992 if (llc->dev) {
993 sllc.sllc_arphrd = llc->dev->type;
994 memcpy(&sllc.sllc_mac, llc->dev->dev_addr,
995 IFHWADDRLEN);
996 }
997 }
998 rc = 0;
999 sllc.sllc_family = AF_LLC;
1000 memcpy(uaddr, &sllc, sizeof(sllc));
1001 out:
1002 release_sock(sk);
1003 return rc;
1004 }
1005
1006 /**
1007 * llc_ui_ioctl - io controls for PF_LLC
1008 * @sock: Socket to get/set info
1009 * @cmd: command
1010 * @arg: optional argument for cmd
1011 *
1012 * get/set info on llc sockets
1013 */
1014 static int llc_ui_ioctl(struct socket *sock, unsigned int cmd,
1015 unsigned long arg)
1016 {
1017 return -ENOIOCTLCMD;
1018 }
1019
1020 /**
1021 * llc_ui_setsockopt - set various connection specific parameters.
1022 * @sock: Socket to set options on.
1023 * @level: Socket level user is requesting operations on.
1024 * @optname: Operation name.
1025 * @optval: User provided operation data.
1026 * @optlen: Length of optval.
1027 *
1028 * Set various connection specific parameters.
1029 */
1030 static int llc_ui_setsockopt(struct socket *sock, int level, int optname,
1031 char __user *optval, unsigned int optlen)
1032 {
1033 struct sock *sk = sock->sk;
1034 struct llc_sock *llc = llc_sk(sk);
1035 unsigned int opt;
1036 int rc = -EINVAL;
1037
1038 lock_sock(sk);
1039 if (unlikely(level != SOL_LLC || optlen != sizeof(int)))
1040 goto out;
1041 rc = get_user(opt, (int __user *)optval);
1042 if (rc)
1043 goto out;
1044 rc = -EINVAL;
1045 switch (optname) {
1046 case LLC_OPT_RETRY:
1047 if (opt > LLC_OPT_MAX_RETRY)
1048 goto out;
1049 llc->n2 = opt;
1050 break;
1051 case LLC_OPT_SIZE:
1052 if (opt > LLC_OPT_MAX_SIZE)
1053 goto out;
1054 llc->n1 = opt;
1055 break;
1056 case LLC_OPT_ACK_TMR_EXP:
1057 if (opt > LLC_OPT_MAX_ACK_TMR_EXP)
1058 goto out;
1059 llc->ack_timer.expire = opt * HZ;
1060 break;
1061 case LLC_OPT_P_TMR_EXP:
1062 if (opt > LLC_OPT_MAX_P_TMR_EXP)
1063 goto out;
1064 llc->pf_cycle_timer.expire = opt * HZ;
1065 break;
1066 case LLC_OPT_REJ_TMR_EXP:
1067 if (opt > LLC_OPT_MAX_REJ_TMR_EXP)
1068 goto out;
1069 llc->rej_sent_timer.expire = opt * HZ;
1070 break;
1071 case LLC_OPT_BUSY_TMR_EXP:
1072 if (opt > LLC_OPT_MAX_BUSY_TMR_EXP)
1073 goto out;
1074 llc->busy_state_timer.expire = opt * HZ;
1075 break;
1076 case LLC_OPT_TX_WIN:
1077 if (opt > LLC_OPT_MAX_WIN)
1078 goto out;
1079 llc->k = opt;
1080 break;
1081 case LLC_OPT_RX_WIN:
1082 if (opt > LLC_OPT_MAX_WIN)
1083 goto out;
1084 llc->rw = opt;
1085 break;
1086 case LLC_OPT_PKTINFO:
1087 if (opt)
1088 llc->cmsg_flags |= LLC_CMSG_PKTINFO;
1089 else
1090 llc->cmsg_flags &= ~LLC_CMSG_PKTINFO;
1091 break;
1092 default:
1093 rc = -ENOPROTOOPT;
1094 goto out;
1095 }
1096 rc = 0;
1097 out:
1098 release_sock(sk);
1099 return rc;
1100 }
1101
1102 /**
1103 * llc_ui_getsockopt - get connection specific socket info
1104 * @sock: Socket to get information from.
1105 * @level: Socket level user is requesting operations on.
1106 * @optname: Operation name.
1107 * @optval: Variable to return operation data in.
1108 * @optlen: Length of optval.
1109 *
1110 * Get connection specific socket information.
1111 */
1112 static int llc_ui_getsockopt(struct socket *sock, int level, int optname,
1113 char __user *optval, int __user *optlen)
1114 {
1115 struct sock *sk = sock->sk;
1116 struct llc_sock *llc = llc_sk(sk);
1117 int val = 0, len = 0, rc = -EINVAL;
1118
1119 lock_sock(sk);
1120 if (unlikely(level != SOL_LLC))
1121 goto out;
1122 rc = get_user(len, optlen);
1123 if (rc)
1124 goto out;
1125 rc = -EINVAL;
1126 if (len != sizeof(int))
1127 goto out;
1128 switch (optname) {
1129 case LLC_OPT_RETRY:
1130 val = llc->n2; break;
1131 case LLC_OPT_SIZE:
1132 val = llc->n1; break;
1133 case LLC_OPT_ACK_TMR_EXP:
1134 val = llc->ack_timer.expire / HZ; break;
1135 case LLC_OPT_P_TMR_EXP:
1136 val = llc->pf_cycle_timer.expire / HZ; break;
1137 case LLC_OPT_REJ_TMR_EXP:
1138 val = llc->rej_sent_timer.expire / HZ; break;
1139 case LLC_OPT_BUSY_TMR_EXP:
1140 val = llc->busy_state_timer.expire / HZ; break;
1141 case LLC_OPT_TX_WIN:
1142 val = llc->k; break;
1143 case LLC_OPT_RX_WIN:
1144 val = llc->rw; break;
1145 case LLC_OPT_PKTINFO:
1146 val = (llc->cmsg_flags & LLC_CMSG_PKTINFO) != 0;
1147 break;
1148 default:
1149 rc = -ENOPROTOOPT;
1150 goto out;
1151 }
1152 rc = 0;
1153 if (put_user(len, optlen) || copy_to_user(optval, &val, len))
1154 rc = -EFAULT;
1155 out:
1156 release_sock(sk);
1157 return rc;
1158 }
1159
1160 static const struct net_proto_family llc_ui_family_ops = {
1161 .family = PF_LLC,
1162 .create = llc_ui_create,
1163 .owner = THIS_MODULE,
1164 };
1165
1166 static const struct proto_ops llc_ui_ops = {
1167 .family = PF_LLC,
1168 .owner = THIS_MODULE,
1169 .release = llc_ui_release,
1170 .bind = llc_ui_bind,
1171 .connect = llc_ui_connect,
1172 .socketpair = sock_no_socketpair,
1173 .accept = llc_ui_accept,
1174 .getname = llc_ui_getname,
1175 .poll = datagram_poll,
1176 .ioctl = llc_ui_ioctl,
1177 .listen = llc_ui_listen,
1178 .shutdown = llc_ui_shutdown,
1179 .setsockopt = llc_ui_setsockopt,
1180 .getsockopt = llc_ui_getsockopt,
1181 .sendmsg = llc_ui_sendmsg,
1182 .recvmsg = llc_ui_recvmsg,
1183 .mmap = sock_no_mmap,
1184 .sendpage = sock_no_sendpage,
1185 };
1186
1187 static const char llc_proc_err_msg[] __initconst =
1188 KERN_CRIT "LLC: Unable to register the proc_fs entries\n";
1189 static const char llc_sysctl_err_msg[] __initconst =
1190 KERN_CRIT "LLC: Unable to register the sysctl entries\n";
1191 static const char llc_sock_err_msg[] __initconst =
1192 KERN_CRIT "LLC: Unable to register the network family\n";
1193
1194 static int __init llc2_init(void)
1195 {
1196 int rc = proto_register(&llc_proto, 0);
1197
1198 if (rc != 0)
1199 goto out;
1200
1201 llc_build_offset_table();
1202 llc_station_init();
1203 llc_ui_sap_last_autoport = LLC_SAP_DYN_START;
1204 rc = llc_proc_init();
1205 if (rc != 0) {
1206 printk(llc_proc_err_msg);
1207 goto out_station;
1208 }
1209 rc = llc_sysctl_init();
1210 if (rc) {
1211 printk(llc_sysctl_err_msg);
1212 goto out_proc;
1213 }
1214 rc = sock_register(&llc_ui_family_ops);
1215 if (rc) {
1216 printk(llc_sock_err_msg);
1217 goto out_sysctl;
1218 }
1219 llc_add_pack(LLC_DEST_SAP, llc_sap_handler);
1220 llc_add_pack(LLC_DEST_CONN, llc_conn_handler);
1221 out:
1222 return rc;
1223 out_sysctl:
1224 llc_sysctl_exit();
1225 out_proc:
1226 llc_proc_exit();
1227 out_station:
1228 llc_station_exit();
1229 proto_unregister(&llc_proto);
1230 goto out;
1231 }
1232
1233 static void __exit llc2_exit(void)
1234 {
1235 llc_station_exit();
1236 llc_remove_pack(LLC_DEST_SAP);
1237 llc_remove_pack(LLC_DEST_CONN);
1238 sock_unregister(PF_LLC);
1239 llc_proc_exit();
1240 llc_sysctl_exit();
1241 proto_unregister(&llc_proto);
1242 }
1243
1244 module_init(llc2_init);
1245 module_exit(llc2_exit);
1246
1247 MODULE_LICENSE("GPL");
1248 MODULE_AUTHOR("Procom 1997, Jay Schullist 2001, Arnaldo C. Melo 2001-2003");
1249 MODULE_DESCRIPTION("IEEE 802.2 PF_LLC support");
1250 MODULE_ALIAS_NETPROTO(PF_LLC);
Linux with added FPC-III support