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Merge tag 'chrome-platform-for-linus-4.13' of git://git.kernel.org/pub/scm/linux...
[linux/fpc-iii.git] / net / llc / af_llc.c
blobc38d16f22d2a7ff265b8729d43b164312598fd9f
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...)
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 */
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 */
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 */
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 */
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 || addr->sllc_xid)
102 rc = LLC_PDU_LEN_U;
103 else if (sk->sk_type == SOCK_STREAM)
104 rc = LLC_PDU_LEN_I;
105 return rc;
106 }
107
108 /**
109 * llc_ui_send_data - send data via reliable llc2 connection
110 * @sk: Connection the socket is using.
111 * @skb: Data the user wishes to send.
112 * @noblock: can we block waiting for data?
113 *
114 * Send data via reliable llc2 connection.
115 * Returns 0 upon success, non-zero if action did not succeed.
116 */
117 static int llc_ui_send_data(struct sock* sk, struct sk_buff *skb, int noblock)
118 {
119 struct llc_sock* llc = llc_sk(sk);
120 int rc = 0;
121
122 if (unlikely(llc_data_accept_state(llc->state) ||
123 llc->remote_busy_flag ||
124 llc->p_flag)) {
125 long timeout = sock_sndtimeo(sk, noblock);
126
127 rc = llc_ui_wait_for_busy_core(sk, timeout);
128 }
129 if (unlikely(!rc))
130 rc = llc_build_and_send_pkt(sk, skb);
131 return rc;
132 }
133
134 static void llc_ui_sk_init(struct socket *sock, struct sock *sk)
135 {
136 sock_graft(sk, sock);
137 sk->sk_type = sock->type;
138 sock->ops = &llc_ui_ops;
139 }
140
141 static struct proto llc_proto = {
142 .name = "LLC",
143 .owner = THIS_MODULE,
144 .obj_size = sizeof(struct llc_sock),
145 .slab_flags = SLAB_TYPESAFE_BY_RCU,
146 };
147
148 /**
149 * llc_ui_create - alloc and init a new llc_ui socket
150 * @net: network namespace (must be default network)
151 * @sock: Socket to initialize and attach allocated sk to.
152 * @protocol: Unused.
153 * @kern: on behalf of kernel or userspace
154 *
155 * Allocate and initialize a new llc_ui socket, validate the user wants a
156 * socket type we have available.
157 * Returns 0 upon success, negative upon failure.
158 */
159 static int llc_ui_create(struct net *net, struct socket *sock, int protocol,
160 int kern)
161 {
162 struct sock *sk;
163 int rc = -ESOCKTNOSUPPORT;
164
165 if (!ns_capable(net->user_ns, CAP_NET_RAW))
166 return -EPERM;
167
168 if (!net_eq(net, &init_net))
169 return -EAFNOSUPPORT;
170
171 if (likely(sock->type == SOCK_DGRAM || sock->type == SOCK_STREAM)) {
172 rc = -ENOMEM;
173 sk = llc_sk_alloc(net, PF_LLC, GFP_KERNEL, &llc_proto, kern);
174 if (sk) {
175 rc = 0;
176 llc_ui_sk_init(sock, sk);
177 }
178 }
179 return rc;
180 }
181
182 /**
183 * llc_ui_release - shutdown socket
184 * @sock: Socket to release.
185 *
186 * Shutdown and deallocate an existing socket.
187 */
188 static int llc_ui_release(struct socket *sock)
189 {
190 struct sock *sk = sock->sk;
191 struct llc_sock *llc;
192
193 if (unlikely(sk == NULL))
194 goto out;
195 sock_hold(sk);
196 lock_sock(sk);
197 llc = llc_sk(sk);
198 dprintk("%s: closing local(%02X) remote(%02X)\n", __func__,
199 llc->laddr.lsap, llc->daddr.lsap);
200 if (!llc_send_disc(sk))
201 llc_ui_wait_for_disc(sk, sk->sk_rcvtimeo);
202 if (!sock_flag(sk, SOCK_ZAPPED))
203 llc_sap_remove_socket(llc->sap, sk);
204 release_sock(sk);
205 if (llc->dev)
206 dev_put(llc->dev);
207 sock_put(sk);
208 llc_sk_free(sk);
209 out:
210 return 0;
211 }
212
213 /**
214 * llc_ui_autoport - provide dynamically allocate SAP number
215 *
216 * Provide the caller with a dynamically allocated SAP number according
217 * to the rules that are set in this function. Returns: 0, upon failure,
218 * SAP number otherwise.
219 */
220 static int llc_ui_autoport(void)
221 {
222 struct llc_sap *sap;
223 int i, tries = 0;
224
225 while (tries < LLC_SAP_DYN_TRIES) {
226 for (i = llc_ui_sap_last_autoport;
227 i < LLC_SAP_DYN_STOP; i += 2) {
228 sap = llc_sap_find(i);
229 if (!sap) {
230 llc_ui_sap_last_autoport = i + 2;
231 goto out;
232 }
233 llc_sap_put(sap);
234 }
235 llc_ui_sap_last_autoport = LLC_SAP_DYN_START;
236 tries++;
237 }
238 i = 0;
239 out:
240 return i;
241 }
242
243 /**
244 * llc_ui_autobind - automatically bind a socket to a sap
245 * @sock: socket to bind
246 * @addr: address to connect to
247 *
248 * Used by llc_ui_connect and llc_ui_sendmsg when the user hasn't
249 * specifically used llc_ui_bind to bind to an specific address/sap
250 *
251 * Returns: 0 upon success, negative otherwise.
252 */
253 static int llc_ui_autobind(struct socket *sock, struct sockaddr_llc *addr)
254 {
255 struct sock *sk = sock->sk;
256 struct llc_sock *llc = llc_sk(sk);
257 struct llc_sap *sap;
258 int rc = -EINVAL;
259
260 if (!sock_flag(sk, SOCK_ZAPPED))
261 goto out;
262 rc = -ENODEV;
263 if (sk->sk_bound_dev_if) {
264 llc->dev = dev_get_by_index(&init_net, sk->sk_bound_dev_if);
265 if (llc->dev && addr->sllc_arphrd != llc->dev->type) {
266 dev_put(llc->dev);
267 llc->dev = NULL;
268 }
269 } else
270 llc->dev = dev_getfirstbyhwtype(&init_net, addr->sllc_arphrd);
271 if (!llc->dev)
272 goto out;
273 rc = -EUSERS;
274 llc->laddr.lsap = llc_ui_autoport();
275 if (!llc->laddr.lsap)
276 goto out;
277 rc = -EBUSY; /* some other network layer is using the sap */
278 sap = llc_sap_open(llc->laddr.lsap, NULL);
279 if (!sap)
280 goto out;
281 memcpy(llc->laddr.mac, llc->dev->dev_addr, IFHWADDRLEN);
282 memcpy(&llc->addr, addr, sizeof(llc->addr));
283 /* assign new connection to its SAP */
284 llc_sap_add_socket(sap, sk);
285 sock_reset_flag(sk, SOCK_ZAPPED);
286 rc = 0;
287 out:
288 return rc;
289 }
290
291 /**
292 * llc_ui_bind - bind a socket to a specific address.
293 * @sock: Socket to bind an address to.
294 * @uaddr: Address the user wants the socket bound to.
295 * @addrlen: Length of the uaddr structure.
296 *
297 * Bind a socket to a specific address. For llc a user is able to bind to
298 * a specific sap only or mac + sap.
299 * If the user desires to bind to a specific mac + sap, it is possible to
300 * have multiple sap connections via multiple macs.
301 * Bind and autobind for that matter must enforce the correct sap usage
302 * otherwise all hell will break loose.
303 * Returns: 0 upon success, negative otherwise.
304 */
305 static int llc_ui_bind(struct socket *sock, struct sockaddr *uaddr, int addrlen)
306 {
307 struct sockaddr_llc *addr = (struct sockaddr_llc *)uaddr;
308 struct sock *sk = sock->sk;
309 struct llc_sock *llc = llc_sk(sk);
310 struct llc_sap *sap;
311 int rc = -EINVAL;
312
313 dprintk("%s: binding %02X\n", __func__, addr->sllc_sap);
314
315 lock_sock(sk);
316 if (unlikely(!sock_flag(sk, SOCK_ZAPPED) || addrlen != sizeof(*addr)))
317 goto out;
318 rc = -EAFNOSUPPORT;
319 if (unlikely(addr->sllc_family != AF_LLC))
320 goto out;
321 rc = -ENODEV;
322 rcu_read_lock();
323 if (sk->sk_bound_dev_if) {
324 llc->dev = dev_get_by_index_rcu(&init_net, sk->sk_bound_dev_if);
325 if (llc->dev) {
326 if (!addr->sllc_arphrd)
327 addr->sllc_arphrd = llc->dev->type;
328 if (is_zero_ether_addr(addr->sllc_mac))
329 memcpy(addr->sllc_mac, llc->dev->dev_addr,
330 IFHWADDRLEN);
331 if (addr->sllc_arphrd != llc->dev->type ||
332 !ether_addr_equal(addr->sllc_mac,
333 llc->dev->dev_addr)) {
334 rc = -EINVAL;
335 llc->dev = NULL;
336 }
337 }
338 } else
339 llc->dev = dev_getbyhwaddr_rcu(&init_net, addr->sllc_arphrd,
340 addr->sllc_mac);
341 if (llc->dev)
342 dev_hold(llc->dev);
343 rcu_read_unlock();
344 if (!llc->dev)
345 goto out;
346 if (!addr->sllc_sap) {
347 rc = -EUSERS;
348 addr->sllc_sap = llc_ui_autoport();
349 if (!addr->sllc_sap)
350 goto out;
351 }
352 sap = llc_sap_find(addr->sllc_sap);
353 if (!sap) {
354 sap = llc_sap_open(addr->sllc_sap, NULL);
355 rc = -EBUSY; /* some other network layer is using the sap */
356 if (!sap)
357 goto out;
358 } else {
359 struct llc_addr laddr, daddr;
360 struct sock *ask;
361
362 memset(&laddr, 0, sizeof(laddr));
363 memset(&daddr, 0, sizeof(daddr));
364 /*
365 * FIXME: check if the address is multicast,
366 * only SOCK_DGRAM can do this.
367 */
368 memcpy(laddr.mac, addr->sllc_mac, IFHWADDRLEN);
369 laddr.lsap = addr->sllc_sap;
370 rc = -EADDRINUSE; /* mac + sap clash. */
371 ask = llc_lookup_established(sap, &daddr, &laddr);
372 if (ask) {
373 sock_put(ask);
374 goto out_put;
375 }
376 }
377 llc->laddr.lsap = addr->sllc_sap;
378 memcpy(llc->laddr.mac, addr->sllc_mac, IFHWADDRLEN);
379 memcpy(&llc->addr, addr, sizeof(llc->addr));
380 /* assign new connection to its SAP */
381 llc_sap_add_socket(sap, sk);
382 sock_reset_flag(sk, SOCK_ZAPPED);
383 rc = 0;
384 out_put:
385 llc_sap_put(sap);
386 out:
387 release_sock(sk);
388 return rc;
389 }
390
391 /**
392 * llc_ui_shutdown - shutdown a connect llc2 socket.
393 * @sock: Socket to shutdown.
394 * @how: What part of the socket to shutdown.
395 *
396 * Shutdown a connected llc2 socket. Currently this function only supports
397 * shutting down both sends and receives (2), we could probably make this
398 * function such that a user can shutdown only half the connection but not
399 * right now.
400 * Returns: 0 upon success, negative otherwise.
401 */
402 static int llc_ui_shutdown(struct socket *sock, int how)
403 {
404 struct sock *sk = sock->sk;
405 int rc = -ENOTCONN;
406
407 lock_sock(sk);
408 if (unlikely(sk->sk_state != TCP_ESTABLISHED))
409 goto out;
410 rc = -EINVAL;
411 if (how != 2)
412 goto out;
413 rc = llc_send_disc(sk);
414 if (!rc)
415 rc = llc_ui_wait_for_disc(sk, sk->sk_rcvtimeo);
416 /* Wake up anyone sleeping in poll */
417 sk->sk_state_change(sk);
418 out:
419 release_sock(sk);
420 return rc;
421 }
422
423 /**
424 * llc_ui_connect - Connect to a remote llc2 mac + sap.
425 * @sock: Socket which will be connected to the remote destination.
426 * @uaddr: Remote and possibly the local address of the new connection.
427 * @addrlen: Size of uaddr structure.
428 * @flags: Operational flags specified by the user.
429 *
430 * Connect to a remote llc2 mac + sap. The caller must specify the
431 * destination mac and address to connect to. If the user hasn't previously
432 * called bind(2) with a smac the address of the first interface of the
433 * specified arp type will be used.
434 * This function will autobind if user did not previously call bind.
435 * Returns: 0 upon success, negative otherwise.
436 */
437 static int llc_ui_connect(struct socket *sock, struct sockaddr *uaddr,
438 int addrlen, int flags)
439 {
440 struct sock *sk = sock->sk;
441 struct llc_sock *llc = llc_sk(sk);
442 struct sockaddr_llc *addr = (struct sockaddr_llc *)uaddr;
443 int rc = -EINVAL;
444
445 lock_sock(sk);
446 if (unlikely(addrlen != sizeof(*addr)))
447 goto out;
448 rc = -EAFNOSUPPORT;
449 if (unlikely(addr->sllc_family != AF_LLC))
450 goto out;
451 if (unlikely(sk->sk_type != SOCK_STREAM))
452 goto out;
453 rc = -EALREADY;
454 if (unlikely(sock->state == SS_CONNECTING))
455 goto out;
456 /* bind connection to sap if user hasn't done it. */
457 if (sock_flag(sk, SOCK_ZAPPED)) {
458 /* bind to sap with null dev, exclusive */
459 rc = llc_ui_autobind(sock, addr);
460 if (rc)
461 goto out;
462 }
463 llc->daddr.lsap = addr->sllc_sap;
464 memcpy(llc->daddr.mac, addr->sllc_mac, IFHWADDRLEN);
465 sock->state = SS_CONNECTING;
466 sk->sk_state = TCP_SYN_SENT;
467 llc->link = llc_ui_next_link_no(llc->sap->laddr.lsap);
468 rc = llc_establish_connection(sk, llc->dev->dev_addr,
469 addr->sllc_mac, addr->sllc_sap);
470 if (rc) {
471 dprintk("%s: llc_ui_send_conn failed :-(\n", __func__);
472 sock->state = SS_UNCONNECTED;
473 sk->sk_state = TCP_CLOSE;
474 goto out;
475 }
476
477 if (sk->sk_state == TCP_SYN_SENT) {
478 const long timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
479
480 if (!timeo || !llc_ui_wait_for_conn(sk, timeo))
481 goto out;
482
483 rc = sock_intr_errno(timeo);
484 if (signal_pending(current))
485 goto out;
486 }
487
488 if (sk->sk_state == TCP_CLOSE)
489 goto sock_error;
490
491 sock->state = SS_CONNECTED;
492 rc = 0;
493 out:
494 release_sock(sk);
495 return rc;
496 sock_error:
497 rc = sock_error(sk) ? : -ECONNABORTED;
498 sock->state = SS_UNCONNECTED;
499 goto out;
500 }
501
502 /**
503 * llc_ui_listen - allow a normal socket to accept incoming connections
504 * @sock: Socket to allow incoming connections on.
505 * @backlog: Number of connections to queue.
506 *
507 * Allow a normal socket to accept incoming connections.
508 * Returns 0 upon success, negative otherwise.
509 */
510 static int llc_ui_listen(struct socket *sock, int backlog)
511 {
512 struct sock *sk = sock->sk;
513 int rc = -EINVAL;
514
515 lock_sock(sk);
516 if (unlikely(sock->state != SS_UNCONNECTED))
517 goto out;
518 rc = -EOPNOTSUPP;
519 if (unlikely(sk->sk_type != SOCK_STREAM))
520 goto out;
521 rc = -EAGAIN;
522 if (sock_flag(sk, SOCK_ZAPPED))
523 goto out;
524 rc = 0;
525 if (!(unsigned int)backlog) /* BSDism */
526 backlog = 1;
527 sk->sk_max_ack_backlog = backlog;
528 if (sk->sk_state != TCP_LISTEN) {
529 sk->sk_ack_backlog = 0;
530 sk->sk_state = TCP_LISTEN;
531 }
532 sk->sk_socket->flags |= __SO_ACCEPTCON;
533 out:
534 release_sock(sk);
535 return rc;
536 }
537
538 static int llc_ui_wait_for_disc(struct sock *sk, long timeout)
539 {
540 DEFINE_WAIT_FUNC(wait, woken_wake_function);
541 int rc = 0;
542
543 add_wait_queue(sk_sleep(sk), &wait);
544 while (1) {
545 if (sk_wait_event(sk, &timeout, sk->sk_state == TCP_CLOSE, &wait))
546 break;
547 rc = -ERESTARTSYS;
548 if (signal_pending(current))
549 break;
550 rc = -EAGAIN;
551 if (!timeout)
552 break;
553 rc = 0;
554 }
555 remove_wait_queue(sk_sleep(sk), &wait);
556 return rc;
557 }
558
559 static bool llc_ui_wait_for_conn(struct sock *sk, long timeout)
560 {
561 DEFINE_WAIT_FUNC(wait, woken_wake_function);
562
563 add_wait_queue(sk_sleep(sk), &wait);
564 while (1) {
565 if (sk_wait_event(sk, &timeout, sk->sk_state != TCP_SYN_SENT, &wait))
566 break;
567 if (signal_pending(current) || !timeout)
568 break;
569 }
570 remove_wait_queue(sk_sleep(sk), &wait);
571 return timeout;
572 }
573
574 static int llc_ui_wait_for_busy_core(struct sock *sk, long timeout)
575 {
576 DEFINE_WAIT_FUNC(wait, woken_wake_function);
577 struct llc_sock *llc = llc_sk(sk);
578 int rc;
579
580 add_wait_queue(sk_sleep(sk), &wait);
581 while (1) {
582 rc = 0;
583 if (sk_wait_event(sk, &timeout,
584 (sk->sk_shutdown & RCV_SHUTDOWN) ||
585 (!llc_data_accept_state(llc->state) &&
586 !llc->remote_busy_flag &&
587 !llc->p_flag), &wait))
588 break;
589 rc = -ERESTARTSYS;
590 if (signal_pending(current))
591 break;
592 rc = -EAGAIN;
593 if (!timeout)
594 break;
595 }
596 remove_wait_queue(sk_sleep(sk), &wait);
597 return rc;
598 }
599
600 static int llc_wait_data(struct sock *sk, long timeo)
601 {
602 int rc;
603
604 while (1) {
605 /*
606 * POSIX 1003.1g mandates this order.
607 */
608 rc = sock_error(sk);
609 if (rc)
610 break;
611 rc = 0;
612 if (sk->sk_shutdown & RCV_SHUTDOWN)
613 break;
614 rc = -EAGAIN;
615 if (!timeo)
616 break;
617 rc = sock_intr_errno(timeo);
618 if (signal_pending(current))
619 break;
620 rc = 0;
621 if (sk_wait_data(sk, &timeo, NULL))
622 break;
623 }
624 return rc;
625 }
626
627 static void llc_cmsg_rcv(struct msghdr *msg, struct sk_buff *skb)
628 {
629 struct llc_sock *llc = llc_sk(skb->sk);
630
631 if (llc->cmsg_flags & LLC_CMSG_PKTINFO) {
632 struct llc_pktinfo info;
633
634 memset(&info, 0, sizeof(info));
635 info.lpi_ifindex = llc_sk(skb->sk)->dev->ifindex;
636 llc_pdu_decode_dsap(skb, &info.lpi_sap);
637 llc_pdu_decode_da(skb, info.lpi_mac);
638 put_cmsg(msg, SOL_LLC, LLC_OPT_PKTINFO, sizeof(info), &info);
639 }
640 }
641
642 /**
643 * llc_ui_accept - accept a new incoming connection.
644 * @sock: Socket which connections arrive on.
645 * @newsock: Socket to move incoming connection to.
646 * @flags: User specified operational flags.
647 * @kern: If the socket is kernel internal
648 *
649 * Accept a new incoming connection.
650 * Returns 0 upon success, negative otherwise.
651 */
652 static int llc_ui_accept(struct socket *sock, struct socket *newsock, int flags,
653 bool kern)
654 {
655 struct sock *sk = sock->sk, *newsk;
656 struct llc_sock *llc, *newllc;
657 struct sk_buff *skb;
658 int rc = -EOPNOTSUPP;
659
660 dprintk("%s: accepting on %02X\n", __func__,
661 llc_sk(sk)->laddr.lsap);
662 lock_sock(sk);
663 if (unlikely(sk->sk_type != SOCK_STREAM))
664 goto out;
665 rc = -EINVAL;
666 if (unlikely(sock->state != SS_UNCONNECTED ||
667 sk->sk_state != TCP_LISTEN))
668 goto out;
669 /* wait for a connection to arrive. */
670 if (skb_queue_empty(&sk->sk_receive_queue)) {
671 rc = llc_wait_data(sk, sk->sk_rcvtimeo);
672 if (rc)
673 goto out;
674 }
675 dprintk("%s: got a new connection on %02X\n", __func__,
676 llc_sk(sk)->laddr.lsap);
677 skb = skb_dequeue(&sk->sk_receive_queue);
678 rc = -EINVAL;
679 if (!skb->sk)
680 goto frees;
681 rc = 0;
682 newsk = skb->sk;
683 /* attach connection to a new socket. */
684 llc_ui_sk_init(newsock, newsk);
685 sock_reset_flag(newsk, SOCK_ZAPPED);
686 newsk->sk_state = TCP_ESTABLISHED;
687 newsock->state = SS_CONNECTED;
688 llc = llc_sk(sk);
689 newllc = llc_sk(newsk);
690 memcpy(&newllc->addr, &llc->addr, sizeof(newllc->addr));
691 newllc->link = llc_ui_next_link_no(newllc->laddr.lsap);
692
693 /* put original socket back into a clean listen state. */
694 sk->sk_state = TCP_LISTEN;
695 sk->sk_ack_backlog--;
696 dprintk("%s: ok success on %02X, client on %02X\n", __func__,
697 llc_sk(sk)->addr.sllc_sap, newllc->daddr.lsap);
698 frees:
699 kfree_skb(skb);
700 out:
701 release_sock(sk);
702 return rc;
703 }
704
705 /**
706 * llc_ui_recvmsg - copy received data to the socket user.
707 * @sock: Socket to copy data from.
708 * @msg: Various user space related information.
709 * @len: Size of user buffer.
710 * @flags: User specified flags.
711 *
712 * Copy received data to the socket user.
713 * Returns non-negative upon success, negative otherwise.
714 */
715 static int llc_ui_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
716 int flags)
717 {
718 DECLARE_SOCKADDR(struct sockaddr_llc *, uaddr, msg->msg_name);
719 const int nonblock = flags & MSG_DONTWAIT;
720 struct sk_buff *skb = NULL;
721 struct sock *sk = sock->sk;
722 struct llc_sock *llc = llc_sk(sk);
723 unsigned long cpu_flags;
724 size_t copied = 0;
725 u32 peek_seq = 0;
726 u32 *seq, skb_len;
727 unsigned long used;
728 int target; /* Read at least this many bytes */
729 long timeo;
730
731 lock_sock(sk);
732 copied = -ENOTCONN;
733 if (unlikely(sk->sk_type == SOCK_STREAM && sk->sk_state == TCP_LISTEN))
734 goto out;
735
736 timeo = sock_rcvtimeo(sk, nonblock);
737
738 seq = &llc->copied_seq;
739 if (flags & MSG_PEEK) {
740 peek_seq = llc->copied_seq;
741 seq = &peek_seq;
742 }
743
744 target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
745 copied = 0;
746
747 do {
748 u32 offset;
749
750 /*
751 * We need to check signals first, to get correct SIGURG
752 * handling. FIXME: Need to check this doesn't impact 1003.1g
753 * and move it down to the bottom of the loop
754 */
755 if (signal_pending(current)) {
756 if (copied)
757 break;
758 copied = timeo ? sock_intr_errno(timeo) : -EAGAIN;
759 break;
760 }
761
762 /* Next get a buffer. */
763
764 skb = skb_peek(&sk->sk_receive_queue);
765 if (skb) {
766 offset = *seq;
767 goto found_ok_skb;
768 }
769 /* Well, if we have backlog, try to process it now yet. */
770
771 if (copied >= target && !sk->sk_backlog.tail)
772 break;
773
774 if (copied) {
775 if (sk->sk_err ||
776 sk->sk_state == TCP_CLOSE ||
777 (sk->sk_shutdown & RCV_SHUTDOWN) ||
778 !timeo ||
779 (flags & MSG_PEEK))
780 break;
781 } else {
782 if (sock_flag(sk, SOCK_DONE))
783 break;
784
785 if (sk->sk_err) {
786 copied = sock_error(sk);
787 break;
788 }
789 if (sk->sk_shutdown & RCV_SHUTDOWN)
790 break;
791
792 if (sk->sk_type == SOCK_STREAM && sk->sk_state == TCP_CLOSE) {
793 if (!sock_flag(sk, SOCK_DONE)) {
794 /*
795 * This occurs when user tries to read
796 * from never connected socket.
797 */
798 copied = -ENOTCONN;
799 break;
800 }
801 break;
802 }
803 if (!timeo) {
804 copied = -EAGAIN;
805 break;
806 }
807 }
808
809 if (copied >= target) { /* Do not sleep, just process backlog. */
810 release_sock(sk);
811 lock_sock(sk);
812 } else
813 sk_wait_data(sk, &timeo, NULL);
814
815 if ((flags & MSG_PEEK) && peek_seq != llc->copied_seq) {
816 net_dbg_ratelimited("LLC(%s:%d): Application bug, race in MSG_PEEK\n",
817 current->comm,
818 task_pid_nr(current));
819 peek_seq = llc->copied_seq;
820 }
821 continue;
822 found_ok_skb:
823 skb_len = skb->len;
824 /* Ok so how much can we use? */
825 used = skb->len - offset;
826 if (len < used)
827 used = len;
828
829 if (!(flags & MSG_TRUNC)) {
830 int rc = skb_copy_datagram_msg(skb, offset, msg, used);
831 if (rc) {
832 /* Exception. Bailout! */
833 if (!copied)
834 copied = -EFAULT;
835 break;
836 }
837 }
838
839 *seq += used;
840 copied += used;
841 len -= used;
842
843 /* For non stream protcols we get one packet per recvmsg call */
844 if (sk->sk_type != SOCK_STREAM)
845 goto copy_uaddr;
846
847 if (!(flags & MSG_PEEK)) {
848 spin_lock_irqsave(&sk->sk_receive_queue.lock, cpu_flags);
849 sk_eat_skb(sk, skb);
850 spin_unlock_irqrestore(&sk->sk_receive_queue.lock, cpu_flags);
851 *seq = 0;
852 }
853
854 /* Partial read */
855 if (used + offset < skb_len)
856 continue;
857 } while (len > 0);
858
859 out:
860 release_sock(sk);
861 return copied;
862 copy_uaddr:
863 if (uaddr != NULL && skb != NULL) {
864 memcpy(uaddr, llc_ui_skb_cb(skb), sizeof(*uaddr));
865 msg->msg_namelen = sizeof(*uaddr);
866 }
867 if (llc_sk(sk)->cmsg_flags)
868 llc_cmsg_rcv(msg, skb);
869
870 if (!(flags & MSG_PEEK)) {
871 spin_lock_irqsave(&sk->sk_receive_queue.lock, cpu_flags);
872 sk_eat_skb(sk, skb);
873 spin_unlock_irqrestore(&sk->sk_receive_queue.lock, cpu_flags);
874 *seq = 0;
875 }
876
877 goto out;
878 }
879
880 /**
881 * llc_ui_sendmsg - Transmit data provided by the socket user.
882 * @sock: Socket to transmit data from.
883 * @msg: Various user related information.
884 * @len: Length of data to transmit.
885 *
886 * Transmit data provided by the socket user.
887 * Returns non-negative upon success, negative otherwise.
888 */
889 static int llc_ui_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
890 {
891 struct sock *sk = sock->sk;
892 struct llc_sock *llc = llc_sk(sk);
893 DECLARE_SOCKADDR(struct sockaddr_llc *, addr, msg->msg_name);
894 int flags = msg->msg_flags;
895 int noblock = flags & MSG_DONTWAIT;
896 struct sk_buff *skb;
897 size_t size = 0;
898 int rc = -EINVAL, copied = 0, hdrlen;
899
900 dprintk("%s: sending from %02X to %02X\n", __func__,
901 llc->laddr.lsap, llc->daddr.lsap);
902 lock_sock(sk);
903 if (addr) {
904 if (msg->msg_namelen < sizeof(*addr))
905 goto release;
906 } else {
907 if (llc_ui_addr_null(&llc->addr))
908 goto release;
909 addr = &llc->addr;
910 }
911 /* must bind connection to sap if user hasn't done it. */
912 if (sock_flag(sk, SOCK_ZAPPED)) {
913 /* bind to sap with null dev, exclusive. */
914 rc = llc_ui_autobind(sock, addr);
915 if (rc)
916 goto release;
917 }
918 hdrlen = llc->dev->hard_header_len + llc_ui_header_len(sk, addr);
919 size = hdrlen + len;
920 if (size > llc->dev->mtu)
921 size = llc->dev->mtu;
922 copied = size - hdrlen;
923 release_sock(sk);
924 skb = sock_alloc_send_skb(sk, size, noblock, &rc);
925 lock_sock(sk);
926 if (!skb)
927 goto release;
928 skb->dev = llc->dev;
929 skb->protocol = llc_proto_type(addr->sllc_arphrd);
930 skb_reserve(skb, hdrlen);
931 rc = memcpy_from_msg(skb_put(skb, copied), msg, copied);
932 if (rc)
933 goto out;
934 if (sk->sk_type == SOCK_DGRAM || addr->sllc_ua) {
935 llc_build_and_send_ui_pkt(llc->sap, skb, addr->sllc_mac,
936 addr->sllc_sap);
937 goto out;
938 }
939 if (addr->sllc_test) {
940 llc_build_and_send_test_pkt(llc->sap, skb, addr->sllc_mac,
941 addr->sllc_sap);
942 goto out;
943 }
944 if (addr->sllc_xid) {
945 llc_build_and_send_xid_pkt(llc->sap, skb, addr->sllc_mac,
946 addr->sllc_sap);
947 goto out;
948 }
949 rc = -ENOPROTOOPT;
950 if (!(sk->sk_type == SOCK_STREAM && !addr->sllc_ua))
951 goto out;
952 rc = llc_ui_send_data(sk, skb, noblock);
953 out:
954 if (rc) {
955 kfree_skb(skb);
956 release:
957 dprintk("%s: failed sending from %02X to %02X: %d\n",
958 __func__, llc->laddr.lsap, llc->daddr.lsap, rc);
959 }
960 release_sock(sk);
961 return rc ? : copied;
962 }
963
964 /**
965 * llc_ui_getname - return the address info of a socket
966 * @sock: Socket to get address of.
967 * @uaddr: Address structure to return information.
968 * @uaddrlen: Length of address structure.
969 * @peer: Does user want local or remote address information.
970 *
971 * Return the address information of a socket.
972 */
973 static int llc_ui_getname(struct socket *sock, struct sockaddr *uaddr,
974 int *uaddrlen, int peer)
975 {
976 struct sockaddr_llc sllc;
977 struct sock *sk = sock->sk;
978 struct llc_sock *llc = llc_sk(sk);
979 int rc = -EBADF;
980
981 memset(&sllc, 0, sizeof(sllc));
982 lock_sock(sk);
983 if (sock_flag(sk, SOCK_ZAPPED))
984 goto out;
985 *uaddrlen = sizeof(sllc);
986 if (peer) {
987 rc = -ENOTCONN;
988 if (sk->sk_state != TCP_ESTABLISHED)
989 goto out;
990 if(llc->dev)
991 sllc.sllc_arphrd = llc->dev->type;
992 sllc.sllc_sap = llc->daddr.lsap;
993 memcpy(&sllc.sllc_mac, &llc->daddr.mac, IFHWADDRLEN);
994 } else {
995 rc = -EINVAL;
996 if (!llc->sap)
997 goto out;
998 sllc.sllc_sap = llc->sap->laddr.lsap;
999
1000 if (llc->dev) {
1001 sllc.sllc_arphrd = llc->dev->type;
1002 memcpy(&sllc.sllc_mac, llc->dev->dev_addr,
1003 IFHWADDRLEN);
1004 }
1005 }
1006 rc = 0;
1007 sllc.sllc_family = AF_LLC;
1008 memcpy(uaddr, &sllc, sizeof(sllc));
1009 out:
1010 release_sock(sk);
1011 return rc;
1012 }
1013
1014 /**
1015 * llc_ui_ioctl - io controls for PF_LLC
1016 * @sock: Socket to get/set info
1017 * @cmd: command
1018 * @arg: optional argument for cmd
1019 *
1020 * get/set info on llc sockets
1021 */
1022 static int llc_ui_ioctl(struct socket *sock, unsigned int cmd,
1023 unsigned long arg)
1024 {
1025 return -ENOIOCTLCMD;
1026 }
1027
1028 /**
1029 * llc_ui_setsockopt - set various connection specific parameters.
1030 * @sock: Socket to set options on.
1031 * @level: Socket level user is requesting operations on.
1032 * @optname: Operation name.
1033 * @optval: User provided operation data.
1034 * @optlen: Length of optval.
1035 *
1036 * Set various connection specific parameters.
1037 */
1038 static int llc_ui_setsockopt(struct socket *sock, int level, int optname,
1039 char __user *optval, unsigned int optlen)
1040 {
1041 struct sock *sk = sock->sk;
1042 struct llc_sock *llc = llc_sk(sk);
1043 unsigned int opt;
1044 int rc = -EINVAL;
1045
1046 lock_sock(sk);
1047 if (unlikely(level != SOL_LLC || optlen != sizeof(int)))
1048 goto out;
1049 rc = get_user(opt, (int __user *)optval);
1050 if (rc)
1051 goto out;
1052 rc = -EINVAL;
1053 switch (optname) {
1054 case LLC_OPT_RETRY:
1055 if (opt > LLC_OPT_MAX_RETRY)
1056 goto out;
1057 llc->n2 = opt;
1058 break;
1059 case LLC_OPT_SIZE:
1060 if (opt > LLC_OPT_MAX_SIZE)
1061 goto out;
1062 llc->n1 = opt;
1063 break;
1064 case LLC_OPT_ACK_TMR_EXP:
1065 if (opt > LLC_OPT_MAX_ACK_TMR_EXP)
1066 goto out;
1067 llc->ack_timer.expire = opt * HZ;
1068 break;
1069 case LLC_OPT_P_TMR_EXP:
1070 if (opt > LLC_OPT_MAX_P_TMR_EXP)
1071 goto out;
1072 llc->pf_cycle_timer.expire = opt * HZ;
1073 break;
1074 case LLC_OPT_REJ_TMR_EXP:
1075 if (opt > LLC_OPT_MAX_REJ_TMR_EXP)
1076 goto out;
1077 llc->rej_sent_timer.expire = opt * HZ;
1078 break;
1079 case LLC_OPT_BUSY_TMR_EXP:
1080 if (opt > LLC_OPT_MAX_BUSY_TMR_EXP)
1081 goto out;
1082 llc->busy_state_timer.expire = opt * HZ;
1083 break;
1084 case LLC_OPT_TX_WIN:
1085 if (opt > LLC_OPT_MAX_WIN)
1086 goto out;
1087 llc->k = opt;
1088 break;
1089 case LLC_OPT_RX_WIN:
1090 if (opt > LLC_OPT_MAX_WIN)
1091 goto out;
1092 llc->rw = opt;
1093 break;
1094 case LLC_OPT_PKTINFO:
1095 if (opt)
1096 llc->cmsg_flags |= LLC_CMSG_PKTINFO;
1097 else
1098 llc->cmsg_flags &= ~LLC_CMSG_PKTINFO;
1099 break;
1100 default:
1101 rc = -ENOPROTOOPT;
1102 goto out;
1103 }
1104 rc = 0;
1105 out:
1106 release_sock(sk);
1107 return rc;
1108 }
1109
1110 /**
1111 * llc_ui_getsockopt - get connection specific socket info
1112 * @sock: Socket to get information from.
1113 * @level: Socket level user is requesting operations on.
1114 * @optname: Operation name.
1115 * @optval: Variable to return operation data in.
1116 * @optlen: Length of optval.
1117 *
1118 * Get connection specific socket information.
1119 */
1120 static int llc_ui_getsockopt(struct socket *sock, int level, int optname,
1121 char __user *optval, int __user *optlen)
1122 {
1123 struct sock *sk = sock->sk;
1124 struct llc_sock *llc = llc_sk(sk);
1125 int val = 0, len = 0, rc = -EINVAL;
1126
1127 lock_sock(sk);
1128 if (unlikely(level != SOL_LLC))
1129 goto out;
1130 rc = get_user(len, optlen);
1131 if (rc)
1132 goto out;
1133 rc = -EINVAL;
1134 if (len != sizeof(int))
1135 goto out;
1136 switch (optname) {
1137 case LLC_OPT_RETRY:
1138 val = llc->n2; break;
1139 case LLC_OPT_SIZE:
1140 val = llc->n1; break;
1141 case LLC_OPT_ACK_TMR_EXP:
1142 val = llc->ack_timer.expire / HZ; break;
1143 case LLC_OPT_P_TMR_EXP:
1144 val = llc->pf_cycle_timer.expire / HZ; break;
1145 case LLC_OPT_REJ_TMR_EXP:
1146 val = llc->rej_sent_timer.expire / HZ; break;
1147 case LLC_OPT_BUSY_TMR_EXP:
1148 val = llc->busy_state_timer.expire / HZ; break;
1149 case LLC_OPT_TX_WIN:
1150 val = llc->k; break;
1151 case LLC_OPT_RX_WIN:
1152 val = llc->rw; break;
1153 case LLC_OPT_PKTINFO:
1154 val = (llc->cmsg_flags & LLC_CMSG_PKTINFO) != 0;
1155 break;
1156 default:
1157 rc = -ENOPROTOOPT;
1158 goto out;
1159 }
1160 rc = 0;
1161 if (put_user(len, optlen) || copy_to_user(optval, &val, len))
1162 rc = -EFAULT;
1163 out:
1164 release_sock(sk);
1165 return rc;
1166 }
1167
1168 static const struct net_proto_family llc_ui_family_ops = {
1169 .family = PF_LLC,
1170 .create = llc_ui_create,
1171 .owner = THIS_MODULE,
1172 };
1173
1174 static const struct proto_ops llc_ui_ops = {
1175 .family = PF_LLC,
1176 .owner = THIS_MODULE,
1177 .release = llc_ui_release,
1178 .bind = llc_ui_bind,
1179 .connect = llc_ui_connect,
1180 .socketpair = sock_no_socketpair,
1181 .accept = llc_ui_accept,
1182 .getname = llc_ui_getname,
1183 .poll = datagram_poll,
1184 .ioctl = llc_ui_ioctl,
1185 .listen = llc_ui_listen,
1186 .shutdown = llc_ui_shutdown,
1187 .setsockopt = llc_ui_setsockopt,
1188 .getsockopt = llc_ui_getsockopt,
1189 .sendmsg = llc_ui_sendmsg,
1190 .recvmsg = llc_ui_recvmsg,
1191 .mmap = sock_no_mmap,
1192 .sendpage = sock_no_sendpage,
1193 };
1194
1195 static const char llc_proc_err_msg[] __initconst =
1196 KERN_CRIT "LLC: Unable to register the proc_fs entries\n";
1197 static const char llc_sysctl_err_msg[] __initconst =
1198 KERN_CRIT "LLC: Unable to register the sysctl entries\n";
1199 static const char llc_sock_err_msg[] __initconst =
1200 KERN_CRIT "LLC: Unable to register the network family\n";
1201
1202 static int __init llc2_init(void)
1203 {
1204 int rc = proto_register(&llc_proto, 0);
1205
1206 if (rc != 0)
1207 goto out;
1208
1209 llc_build_offset_table();
1210 llc_station_init();
1211 llc_ui_sap_last_autoport = LLC_SAP_DYN_START;
1212 rc = llc_proc_init();
1213 if (rc != 0) {
1214 printk(llc_proc_err_msg);
1215 goto out_station;
1216 }
1217 rc = llc_sysctl_init();
1218 if (rc) {
1219 printk(llc_sysctl_err_msg);
1220 goto out_proc;
1221 }
1222 rc = sock_register(&llc_ui_family_ops);
1223 if (rc) {
1224 printk(llc_sock_err_msg);
1225 goto out_sysctl;
1226 }
1227 llc_add_pack(LLC_DEST_SAP, llc_sap_handler);
1228 llc_add_pack(LLC_DEST_CONN, llc_conn_handler);
1229 out:
1230 return rc;
1231 out_sysctl:
1232 llc_sysctl_exit();
1233 out_proc:
1234 llc_proc_exit();
1235 out_station:
1236 llc_station_exit();
1237 proto_unregister(&llc_proto);
1238 goto out;
1239 }
1240
1241 static void __exit llc2_exit(void)
1242 {
1243 llc_station_exit();
1244 llc_remove_pack(LLC_DEST_SAP);
1245 llc_remove_pack(LLC_DEST_CONN);
1246 sock_unregister(PF_LLC);
1247 llc_proc_exit();
1248 llc_sysctl_exit();
1249 proto_unregister(&llc_proto);
1250 }
1251
1252 module_init(llc2_init);
1253 module_exit(llc2_exit);
1254
1255 MODULE_LICENSE("GPL");
1256 MODULE_AUTHOR("Procom 1997, Jay Schullist 2001, Arnaldo C. Melo 2001-2003");
1257 MODULE_DESCRIPTION("IEEE 802.2 PF_LLC support");
1258 MODULE_ALIAS_NETPROTO(PF_LLC);
Linux with added FPC-III support