eCryptfs: Allow 2 scatterlist entries for encrypted filenames
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / net / llc / af_llc.c
blobdfd3a648a55107bda2ff14adb6f9e91c06449240
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.
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.
13 * Copyright (c) 2001 by Jay Schulist <jschlst@samba.org>
14 * 2002-2003 by Arnaldo Carvalho de Melo <acme@conectiva.com.br>
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.
21 * See the GNU General Public License for more details.
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>
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;
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);
45 #if 0
46 #define dprintk(args...) printk(KERN_DEBUG args)
47 #else
48 #define dprintk(args...)
49 #endif
51 /* Maybe we'll add some more in the future. */
52 #define LLC_CMSG_PKTINFO 1
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.
59 * Return the next unused link number for a given sap.
61 static inline u16 llc_ui_next_link_no(int sap)
63 return llc_ui_sap_link_no_max[sap]++;
66 /**
67 * llc_proto_type - return eth protocol for ARP header type
68 * @arphrd: ARP header type.
70 * Given an ARP header type return the corresponding ethernet protocol.
72 static inline __be16 llc_proto_type(u16 arphrd)
74 return arphrd == ARPHRD_IEEE802_TR ?
75 htons(ETH_P_TR_802_2) : htons(ETH_P_802_2);
78 /**
79 * llc_ui_addr_null - determines if a address structure is null
80 * @addr: Address to test if null.
82 static inline u8 llc_ui_addr_null(struct sockaddr_llc *addr)
84 return !memcmp(addr, &llc_ui_addrnull, sizeof(*addr));
87 /**
88 * llc_ui_header_len - return length of llc header based on operation
89 * @sk: Socket which contains a valid llc socket type.
90 * @addr: Complete sockaddr_llc structure received from the user.
92 * Provide the length of the llc header depending on what kind of
93 * operation the user would like to perform and the type of socket.
94 * Returns the correct llc header length.
96 static inline u8 llc_ui_header_len(struct sock *sk, struct sockaddr_llc *addr)
98 u8 rc = LLC_PDU_LEN_U;
100 if (addr->sllc_test || addr->sllc_xid)
101 rc = LLC_PDU_LEN_U;
102 else if (sk->sk_type == SOCK_STREAM)
103 rc = LLC_PDU_LEN_I;
104 return rc;
108 * llc_ui_send_data - send data via reliable llc2 connection
109 * @sk: Connection the socket is using.
110 * @skb: Data the user wishes to send.
111 * @noblock: can we block waiting for data?
113 * Send data via reliable llc2 connection.
114 * Returns 0 upon success, non-zero if action did not succeed.
116 static int llc_ui_send_data(struct sock* sk, struct sk_buff *skb, int noblock)
118 struct llc_sock* llc = llc_sk(sk);
119 int rc = 0;
121 if (unlikely(llc_data_accept_state(llc->state) ||
122 llc->remote_busy_flag ||
123 llc->p_flag)) {
124 long timeout = sock_sndtimeo(sk, noblock);
126 rc = llc_ui_wait_for_busy_core(sk, timeout);
128 if (unlikely(!rc))
129 rc = llc_build_and_send_pkt(sk, skb);
130 return rc;
133 static void llc_ui_sk_init(struct socket *sock, struct sock *sk)
135 sock_graft(sk, sock);
136 sk->sk_type = sock->type;
137 sock->ops = &llc_ui_ops;
140 static struct proto llc_proto = {
141 .name = "LLC",
142 .owner = THIS_MODULE,
143 .obj_size = sizeof(struct llc_sock),
144 .slab_flags = SLAB_DESTROY_BY_RCU,
148 * llc_ui_create - alloc and init a new llc_ui socket
149 * @net: network namespace (must be default network)
150 * @sock: Socket to initialize and attach allocated sk to.
151 * @protocol: Unused.
152 * @kern: on behalf of kernel or userspace
154 * Allocate and initialize a new llc_ui socket, validate the user wants a
155 * socket type we have available.
156 * Returns 0 upon success, negative upon failure.
158 static int llc_ui_create(struct net *net, struct socket *sock, int protocol,
159 int kern)
161 struct sock *sk;
162 int rc = -ESOCKTNOSUPPORT;
164 if (!capable(CAP_NET_RAW))
165 return -EPERM;
167 if (!net_eq(net, &init_net))
168 return -EAFNOSUPPORT;
170 if (likely(sock->type == SOCK_DGRAM || sock->type == SOCK_STREAM)) {
171 rc = -ENOMEM;
172 sk = llc_sk_alloc(net, PF_LLC, GFP_KERNEL, &llc_proto);
173 if (sk) {
174 rc = 0;
175 llc_ui_sk_init(sock, sk);
178 return rc;
182 * llc_ui_release - shutdown socket
183 * @sock: Socket to release.
185 * Shutdown and deallocate an existing socket.
187 static int llc_ui_release(struct socket *sock)
189 struct sock *sk = sock->sk;
190 struct llc_sock *llc;
192 if (unlikely(sk == NULL))
193 goto out;
194 sock_hold(sk);
195 lock_sock(sk);
196 llc = llc_sk(sk);
197 dprintk("%s: closing local(%02X) remote(%02X)\n", __func__,
198 llc->laddr.lsap, llc->daddr.lsap);
199 if (!llc_send_disc(sk))
200 llc_ui_wait_for_disc(sk, sk->sk_rcvtimeo);
201 if (!sock_flag(sk, SOCK_ZAPPED))
202 llc_sap_remove_socket(llc->sap, sk);
203 release_sock(sk);
204 if (llc->dev)
205 dev_put(llc->dev);
206 sock_put(sk);
207 llc_sk_free(sk);
208 out:
209 return 0;
213 * llc_ui_autoport - provide dynamically allocate SAP number
215 * Provide the caller with a dynamically allocated SAP number according
216 * to the rules that are set in this function. Returns: 0, upon failure,
217 * SAP number otherwise.
219 static int llc_ui_autoport(void)
221 struct llc_sap *sap;
222 int i, tries = 0;
224 while (tries < LLC_SAP_DYN_TRIES) {
225 for (i = llc_ui_sap_last_autoport;
226 i < LLC_SAP_DYN_STOP; i += 2) {
227 sap = llc_sap_find(i);
228 if (!sap) {
229 llc_ui_sap_last_autoport = i + 2;
230 goto out;
232 llc_sap_put(sap);
234 llc_ui_sap_last_autoport = LLC_SAP_DYN_START;
235 tries++;
237 i = 0;
238 out:
239 return i;
243 * llc_ui_autobind - automatically bind a socket to a sap
244 * @sock: socket to bind
245 * @addr: address to connect to
247 * Used by llc_ui_connect and llc_ui_sendmsg when the user hasn't
248 * specifically used llc_ui_bind to bind to an specific address/sap
250 * Returns: 0 upon success, negative otherwise.
252 static int llc_ui_autobind(struct socket *sock, struct sockaddr_llc *addr)
254 struct sock *sk = sock->sk;
255 struct llc_sock *llc = llc_sk(sk);
256 struct llc_sap *sap;
257 int rc = -EINVAL;
259 if (!sock_flag(sk, SOCK_ZAPPED))
260 goto out;
261 rc = -ENODEV;
262 if (sk->sk_bound_dev_if) {
263 llc->dev = dev_get_by_index(&init_net, sk->sk_bound_dev_if);
264 if (llc->dev && addr->sllc_arphrd != llc->dev->type) {
265 dev_put(llc->dev);
266 llc->dev = NULL;
268 } else
269 llc->dev = dev_getfirstbyhwtype(&init_net, addr->sllc_arphrd);
270 if (!llc->dev)
271 goto out;
272 rc = -EUSERS;
273 llc->laddr.lsap = llc_ui_autoport();
274 if (!llc->laddr.lsap)
275 goto out;
276 rc = -EBUSY; /* some other network layer is using the sap */
277 sap = llc_sap_open(llc->laddr.lsap, NULL);
278 if (!sap)
279 goto out;
280 memcpy(llc->laddr.mac, llc->dev->dev_addr, IFHWADDRLEN);
281 memcpy(&llc->addr, addr, sizeof(llc->addr));
282 /* assign new connection to its SAP */
283 llc_sap_add_socket(sap, sk);
284 sock_reset_flag(sk, SOCK_ZAPPED);
285 rc = 0;
286 out:
287 return rc;
291 * llc_ui_bind - bind a socket to a specific address.
292 * @sock: Socket to bind an address to.
293 * @uaddr: Address the user wants the socket bound to.
294 * @addrlen: Length of the uaddr structure.
296 * Bind a socket to a specific address. For llc a user is able to bind to
297 * a specific sap only or mac + sap.
298 * If the user desires to bind to a specific mac + sap, it is possible to
299 * have multiple sap connections via multiple macs.
300 * Bind and autobind for that matter must enforce the correct sap usage
301 * otherwise all hell will break loose.
302 * Returns: 0 upon success, negative otherwise.
304 static int llc_ui_bind(struct socket *sock, struct sockaddr *uaddr, int addrlen)
306 struct sockaddr_llc *addr = (struct sockaddr_llc *)uaddr;
307 struct sock *sk = sock->sk;
308 struct llc_sock *llc = llc_sk(sk);
309 struct llc_sap *sap;
310 int rc = -EINVAL;
312 dprintk("%s: binding %02X\n", __func__, addr->sllc_sap);
313 if (unlikely(!sock_flag(sk, SOCK_ZAPPED) || addrlen != sizeof(*addr)))
314 goto out;
315 rc = -EAFNOSUPPORT;
316 if (unlikely(addr->sllc_family != AF_LLC))
317 goto out;
318 rc = -ENODEV;
319 rcu_read_lock();
320 if (sk->sk_bound_dev_if) {
321 llc->dev = dev_get_by_index_rcu(&init_net, sk->sk_bound_dev_if);
322 if (llc->dev) {
323 if (!addr->sllc_arphrd)
324 addr->sllc_arphrd = llc->dev->type;
325 if (llc_mac_null(addr->sllc_mac))
326 memcpy(addr->sllc_mac, llc->dev->dev_addr,
327 IFHWADDRLEN);
328 if (addr->sllc_arphrd != llc->dev->type ||
329 !llc_mac_match(addr->sllc_mac,
330 llc->dev->dev_addr)) {
331 rc = -EINVAL;
332 llc->dev = NULL;
335 } else
336 llc->dev = dev_getbyhwaddr_rcu(&init_net, addr->sllc_arphrd,
337 addr->sllc_mac);
338 if (llc->dev)
339 dev_hold(llc->dev);
340 rcu_read_unlock();
341 if (!llc->dev)
342 goto out;
343 if (!addr->sllc_sap) {
344 rc = -EUSERS;
345 addr->sllc_sap = llc_ui_autoport();
346 if (!addr->sllc_sap)
347 goto out;
349 sap = llc_sap_find(addr->sllc_sap);
350 if (!sap) {
351 sap = llc_sap_open(addr->sllc_sap, NULL);
352 rc = -EBUSY; /* some other network layer is using the sap */
353 if (!sap)
354 goto out;
355 } else {
356 struct llc_addr laddr, daddr;
357 struct sock *ask;
359 memset(&laddr, 0, sizeof(laddr));
360 memset(&daddr, 0, sizeof(daddr));
362 * FIXME: check if the address is multicast,
363 * only SOCK_DGRAM can do this.
365 memcpy(laddr.mac, addr->sllc_mac, IFHWADDRLEN);
366 laddr.lsap = addr->sllc_sap;
367 rc = -EADDRINUSE; /* mac + sap clash. */
368 ask = llc_lookup_established(sap, &daddr, &laddr);
369 if (ask) {
370 sock_put(ask);
371 goto out_put;
374 llc->laddr.lsap = addr->sllc_sap;
375 memcpy(llc->laddr.mac, addr->sllc_mac, IFHWADDRLEN);
376 memcpy(&llc->addr, addr, sizeof(llc->addr));
377 /* assign new connection to its SAP */
378 llc_sap_add_socket(sap, sk);
379 sock_reset_flag(sk, SOCK_ZAPPED);
380 rc = 0;
381 out_put:
382 llc_sap_put(sap);
383 out:
384 return rc;
388 * llc_ui_shutdown - shutdown a connect llc2 socket.
389 * @sock: Socket to shutdown.
390 * @how: What part of the socket to shutdown.
392 * Shutdown a connected llc2 socket. Currently this function only supports
393 * shutting down both sends and receives (2), we could probably make this
394 * function such that a user can shutdown only half the connection but not
395 * right now.
396 * Returns: 0 upon success, negative otherwise.
398 static int llc_ui_shutdown(struct socket *sock, int how)
400 struct sock *sk = sock->sk;
401 int rc = -ENOTCONN;
403 lock_sock(sk);
404 if (unlikely(sk->sk_state != TCP_ESTABLISHED))
405 goto out;
406 rc = -EINVAL;
407 if (how != 2)
408 goto out;
409 rc = llc_send_disc(sk);
410 if (!rc)
411 rc = llc_ui_wait_for_disc(sk, sk->sk_rcvtimeo);
412 /* Wake up anyone sleeping in poll */
413 sk->sk_state_change(sk);
414 out:
415 release_sock(sk);
416 return rc;
420 * llc_ui_connect - Connect to a remote llc2 mac + sap.
421 * @sock: Socket which will be connected to the remote destination.
422 * @uaddr: Remote and possibly the local address of the new connection.
423 * @addrlen: Size of uaddr structure.
424 * @flags: Operational flags specified by the user.
426 * Connect to a remote llc2 mac + sap. The caller must specify the
427 * destination mac and address to connect to. If the user hasn't previously
428 * called bind(2) with a smac the address of the first interface of the
429 * specified arp type will be used.
430 * This function will autobind if user did not previously call bind.
431 * Returns: 0 upon success, negative otherwise.
433 static int llc_ui_connect(struct socket *sock, struct sockaddr *uaddr,
434 int addrlen, int flags)
436 struct sock *sk = sock->sk;
437 struct llc_sock *llc = llc_sk(sk);
438 struct sockaddr_llc *addr = (struct sockaddr_llc *)uaddr;
439 int rc = -EINVAL;
441 lock_sock(sk);
442 if (unlikely(addrlen != sizeof(*addr)))
443 goto out;
444 rc = -EAFNOSUPPORT;
445 if (unlikely(addr->sllc_family != AF_LLC))
446 goto out;
447 if (unlikely(sk->sk_type != SOCK_STREAM))
448 goto out;
449 rc = -EALREADY;
450 if (unlikely(sock->state == SS_CONNECTING))
451 goto out;
452 /* bind connection to sap if user hasn't done it. */
453 if (sock_flag(sk, SOCK_ZAPPED)) {
454 /* bind to sap with null dev, exclusive */
455 rc = llc_ui_autobind(sock, addr);
456 if (rc)
457 goto out;
459 llc->daddr.lsap = addr->sllc_sap;
460 memcpy(llc->daddr.mac, addr->sllc_mac, IFHWADDRLEN);
461 sock->state = SS_CONNECTING;
462 sk->sk_state = TCP_SYN_SENT;
463 llc->link = llc_ui_next_link_no(llc->sap->laddr.lsap);
464 rc = llc_establish_connection(sk, llc->dev->dev_addr,
465 addr->sllc_mac, addr->sllc_sap);
466 if (rc) {
467 dprintk("%s: llc_ui_send_conn failed :-(\n", __func__);
468 sock->state = SS_UNCONNECTED;
469 sk->sk_state = TCP_CLOSE;
470 goto out;
473 if (sk->sk_state == TCP_SYN_SENT) {
474 const long timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
476 if (!timeo || !llc_ui_wait_for_conn(sk, timeo))
477 goto out;
479 rc = sock_intr_errno(timeo);
480 if (signal_pending(current))
481 goto out;
484 if (sk->sk_state == TCP_CLOSE)
485 goto sock_error;
487 sock->state = SS_CONNECTED;
488 rc = 0;
489 out:
490 release_sock(sk);
491 return rc;
492 sock_error:
493 rc = sock_error(sk) ? : -ECONNABORTED;
494 sock->state = SS_UNCONNECTED;
495 goto out;
499 * llc_ui_listen - allow a normal socket to accept incoming connections
500 * @sock: Socket to allow incoming connections on.
501 * @backlog: Number of connections to queue.
503 * Allow a normal socket to accept incoming connections.
504 * Returns 0 upon success, negative otherwise.
506 static int llc_ui_listen(struct socket *sock, int backlog)
508 struct sock *sk = sock->sk;
509 int rc = -EINVAL;
511 lock_sock(sk);
512 if (unlikely(sock->state != SS_UNCONNECTED))
513 goto out;
514 rc = -EOPNOTSUPP;
515 if (unlikely(sk->sk_type != SOCK_STREAM))
516 goto out;
517 rc = -EAGAIN;
518 if (sock_flag(sk, SOCK_ZAPPED))
519 goto out;
520 rc = 0;
521 if (!(unsigned)backlog) /* BSDism */
522 backlog = 1;
523 sk->sk_max_ack_backlog = backlog;
524 if (sk->sk_state != TCP_LISTEN) {
525 sk->sk_ack_backlog = 0;
526 sk->sk_state = TCP_LISTEN;
528 sk->sk_socket->flags |= __SO_ACCEPTCON;
529 out:
530 release_sock(sk);
531 return rc;
534 static int llc_ui_wait_for_disc(struct sock *sk, long timeout)
536 DEFINE_WAIT(wait);
537 int rc = 0;
539 while (1) {
540 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
541 if (sk_wait_event(sk, &timeout, sk->sk_state == TCP_CLOSE))
542 break;
543 rc = -ERESTARTSYS;
544 if (signal_pending(current))
545 break;
546 rc = -EAGAIN;
547 if (!timeout)
548 break;
549 rc = 0;
551 finish_wait(sk_sleep(sk), &wait);
552 return rc;
555 static int llc_ui_wait_for_conn(struct sock *sk, long timeout)
557 DEFINE_WAIT(wait);
559 while (1) {
560 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
561 if (sk_wait_event(sk, &timeout, sk->sk_state != TCP_SYN_SENT))
562 break;
563 if (signal_pending(current) || !timeout)
564 break;
566 finish_wait(sk_sleep(sk), &wait);
567 return timeout;
570 static int llc_ui_wait_for_busy_core(struct sock *sk, long timeout)
572 DEFINE_WAIT(wait);
573 struct llc_sock *llc = llc_sk(sk);
574 int rc;
576 while (1) {
577 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
578 rc = 0;
579 if (sk_wait_event(sk, &timeout,
580 (sk->sk_shutdown & RCV_SHUTDOWN) ||
581 (!llc_data_accept_state(llc->state) &&
582 !llc->remote_busy_flag &&
583 !llc->p_flag)))
584 break;
585 rc = -ERESTARTSYS;
586 if (signal_pending(current))
587 break;
588 rc = -EAGAIN;
589 if (!timeout)
590 break;
592 finish_wait(sk_sleep(sk), &wait);
593 return rc;
596 static int llc_wait_data(struct sock *sk, long timeo)
598 int rc;
600 while (1) {
602 * POSIX 1003.1g mandates this order.
604 rc = sock_error(sk);
605 if (rc)
606 break;
607 rc = 0;
608 if (sk->sk_shutdown & RCV_SHUTDOWN)
609 break;
610 rc = -EAGAIN;
611 if (!timeo)
612 break;
613 rc = sock_intr_errno(timeo);
614 if (signal_pending(current))
615 break;
616 rc = 0;
617 if (sk_wait_data(sk, &timeo))
618 break;
620 return rc;
623 static void llc_cmsg_rcv(struct msghdr *msg, struct sk_buff *skb)
625 struct llc_sock *llc = llc_sk(skb->sk);
627 if (llc->cmsg_flags & LLC_CMSG_PKTINFO) {
628 struct llc_pktinfo info;
630 info.lpi_ifindex = llc_sk(skb->sk)->dev->ifindex;
631 llc_pdu_decode_dsap(skb, &info.lpi_sap);
632 llc_pdu_decode_da(skb, info.lpi_mac);
633 put_cmsg(msg, SOL_LLC, LLC_OPT_PKTINFO, sizeof(info), &info);
638 * llc_ui_accept - accept a new incoming connection.
639 * @sock: Socket which connections arrive on.
640 * @newsock: Socket to move incoming connection to.
641 * @flags: User specified operational flags.
643 * Accept a new incoming connection.
644 * Returns 0 upon success, negative otherwise.
646 static int llc_ui_accept(struct socket *sock, struct socket *newsock, int flags)
648 struct sock *sk = sock->sk, *newsk;
649 struct llc_sock *llc, *newllc;
650 struct sk_buff *skb;
651 int rc = -EOPNOTSUPP;
653 dprintk("%s: accepting on %02X\n", __func__,
654 llc_sk(sk)->laddr.lsap);
655 lock_sock(sk);
656 if (unlikely(sk->sk_type != SOCK_STREAM))
657 goto out;
658 rc = -EINVAL;
659 if (unlikely(sock->state != SS_UNCONNECTED ||
660 sk->sk_state != TCP_LISTEN))
661 goto out;
662 /* wait for a connection to arrive. */
663 if (skb_queue_empty(&sk->sk_receive_queue)) {
664 rc = llc_wait_data(sk, sk->sk_rcvtimeo);
665 if (rc)
666 goto out;
668 dprintk("%s: got a new connection on %02X\n", __func__,
669 llc_sk(sk)->laddr.lsap);
670 skb = skb_dequeue(&sk->sk_receive_queue);
671 rc = -EINVAL;
672 if (!skb->sk)
673 goto frees;
674 rc = 0;
675 newsk = skb->sk;
676 /* attach connection to a new socket. */
677 llc_ui_sk_init(newsock, newsk);
678 sock_reset_flag(newsk, SOCK_ZAPPED);
679 newsk->sk_state = TCP_ESTABLISHED;
680 newsock->state = SS_CONNECTED;
681 llc = llc_sk(sk);
682 newllc = llc_sk(newsk);
683 memcpy(&newllc->addr, &llc->addr, sizeof(newllc->addr));
684 newllc->link = llc_ui_next_link_no(newllc->laddr.lsap);
686 /* put original socket back into a clean listen state. */
687 sk->sk_state = TCP_LISTEN;
688 sk->sk_ack_backlog--;
689 dprintk("%s: ok success on %02X, client on %02X\n", __func__,
690 llc_sk(sk)->addr.sllc_sap, newllc->daddr.lsap);
691 frees:
692 kfree_skb(skb);
693 out:
694 release_sock(sk);
695 return rc;
699 * llc_ui_recvmsg - copy received data to the socket user.
700 * @sock: Socket to copy data from.
701 * @msg: Various user space related information.
702 * @len: Size of user buffer.
703 * @flags: User specified flags.
705 * Copy received data to the socket user.
706 * Returns non-negative upon success, negative otherwise.
708 static int llc_ui_recvmsg(struct kiocb *iocb, struct socket *sock,
709 struct msghdr *msg, size_t len, int flags)
711 struct sockaddr_llc *uaddr = (struct sockaddr_llc *)msg->msg_name;
712 const int nonblock = flags & MSG_DONTWAIT;
713 struct sk_buff *skb = NULL;
714 struct sock *sk = sock->sk;
715 struct llc_sock *llc = llc_sk(sk);
716 size_t copied = 0;
717 u32 peek_seq = 0;
718 u32 *seq;
719 unsigned long used;
720 int target; /* Read at least this many bytes */
721 long timeo;
723 lock_sock(sk);
724 copied = -ENOTCONN;
725 if (unlikely(sk->sk_type == SOCK_STREAM && sk->sk_state == TCP_LISTEN))
726 goto out;
728 timeo = sock_rcvtimeo(sk, nonblock);
730 seq = &llc->copied_seq;
731 if (flags & MSG_PEEK) {
732 peek_seq = llc->copied_seq;
733 seq = &peek_seq;
736 target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
737 copied = 0;
739 do {
740 u32 offset;
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
747 if (signal_pending(current)) {
748 if (copied)
749 break;
750 copied = timeo ? sock_intr_errno(timeo) : -EAGAIN;
751 break;
754 /* Next get a buffer. */
756 skb = skb_peek(&sk->sk_receive_queue);
757 if (skb) {
758 offset = *seq;
759 goto found_ok_skb;
761 /* Well, if we have backlog, try to process it now yet. */
763 if (copied >= target && !sk->sk_backlog.tail)
764 break;
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;
777 if (sk->sk_err) {
778 copied = sock_error(sk);
779 break;
781 if (sk->sk_shutdown & RCV_SHUTDOWN)
782 break;
784 if (sk->sk_type == SOCK_STREAM && sk->sk_state == TCP_CLOSE) {
785 if (!sock_flag(sk, SOCK_DONE)) {
787 * This occurs when user tries to read
788 * from never connected socket.
790 copied = -ENOTCONN;
791 break;
793 break;
795 if (!timeo) {
796 copied = -EAGAIN;
797 break;
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);
807 if ((flags & MSG_PEEK) && peek_seq != llc->copied_seq) {
808 if (net_ratelimit())
809 printk(KERN_DEBUG "LLC(%s:%d): Application "
810 "bug, race in MSG_PEEK.\n",
811 current->comm, task_pid_nr(current));
812 peek_seq = llc->copied_seq;
814 continue;
815 found_ok_skb:
816 /* Ok so how much can we use? */
817 used = skb->len - offset;
818 if (len < used)
819 used = len;
821 if (!(flags & MSG_TRUNC)) {
822 int rc = skb_copy_datagram_iovec(skb, offset,
823 msg->msg_iov, used);
824 if (rc) {
825 /* Exception. Bailout! */
826 if (!copied)
827 copied = -EFAULT;
828 break;
832 *seq += used;
833 copied += used;
834 len -= used;
836 if (!(flags & MSG_PEEK)) {
837 sk_eat_skb(sk, skb, 0);
838 *seq = 0;
841 /* For non stream protcols we get one packet per recvmsg call */
842 if (sk->sk_type != SOCK_STREAM)
843 goto copy_uaddr;
845 /* Partial read */
846 if (used + offset < skb->len)
847 continue;
848 } while (len > 0);
850 out:
851 release_sock(sk);
852 return copied;
853 copy_uaddr:
854 if (uaddr != NULL && skb != NULL) {
855 memcpy(uaddr, llc_ui_skb_cb(skb), sizeof(*uaddr));
856 msg->msg_namelen = sizeof(*uaddr);
858 if (llc_sk(sk)->cmsg_flags)
859 llc_cmsg_rcv(msg, skb);
860 goto out;
864 * llc_ui_sendmsg - Transmit data provided by the socket user.
865 * @sock: Socket to transmit data from.
866 * @msg: Various user related information.
867 * @len: Length of data to transmit.
869 * Transmit data provided by the socket user.
870 * Returns non-negative upon success, negative otherwise.
872 static int llc_ui_sendmsg(struct kiocb *iocb, struct socket *sock,
873 struct msghdr *msg, size_t len)
875 struct sock *sk = sock->sk;
876 struct llc_sock *llc = llc_sk(sk);
877 struct sockaddr_llc *addr = (struct sockaddr_llc *)msg->msg_name;
878 int flags = msg->msg_flags;
879 int noblock = flags & MSG_DONTWAIT;
880 struct sk_buff *skb;
881 size_t size = 0;
882 int rc = -EINVAL, copied = 0, hdrlen;
884 dprintk("%s: sending from %02X to %02X\n", __func__,
885 llc->laddr.lsap, llc->daddr.lsap);
886 lock_sock(sk);
887 if (addr) {
888 if (msg->msg_namelen < sizeof(*addr))
889 goto release;
890 } else {
891 if (llc_ui_addr_null(&llc->addr))
892 goto release;
893 addr = &llc->addr;
895 /* must bind connection to sap if user hasn't done it. */
896 if (sock_flag(sk, SOCK_ZAPPED)) {
897 /* bind to sap with null dev, exclusive. */
898 rc = llc_ui_autobind(sock, addr);
899 if (rc)
900 goto release;
902 hdrlen = llc->dev->hard_header_len + llc_ui_header_len(sk, addr);
903 size = hdrlen + len;
904 if (size > llc->dev->mtu)
905 size = llc->dev->mtu;
906 copied = size - hdrlen;
907 release_sock(sk);
908 skb = sock_alloc_send_skb(sk, size, noblock, &rc);
909 lock_sock(sk);
910 if (!skb)
911 goto release;
912 skb->dev = llc->dev;
913 skb->protocol = llc_proto_type(addr->sllc_arphrd);
914 skb_reserve(skb, hdrlen);
915 rc = memcpy_fromiovec(skb_put(skb, copied), msg->msg_iov, copied);
916 if (rc)
917 goto out;
918 if (sk->sk_type == SOCK_DGRAM || addr->sllc_ua) {
919 llc_build_and_send_ui_pkt(llc->sap, skb, addr->sllc_mac,
920 addr->sllc_sap);
921 goto out;
923 if (addr->sllc_test) {
924 llc_build_and_send_test_pkt(llc->sap, skb, addr->sllc_mac,
925 addr->sllc_sap);
926 goto out;
928 if (addr->sllc_xid) {
929 llc_build_and_send_xid_pkt(llc->sap, skb, addr->sllc_mac,
930 addr->sllc_sap);
931 goto out;
933 rc = -ENOPROTOOPT;
934 if (!(sk->sk_type == SOCK_STREAM && !addr->sllc_ua))
935 goto out;
936 rc = llc_ui_send_data(sk, skb, noblock);
937 out:
938 if (rc) {
939 kfree_skb(skb);
940 release:
941 dprintk("%s: failed sending from %02X to %02X: %d\n",
942 __func__, llc->laddr.lsap, llc->daddr.lsap, rc);
944 release_sock(sk);
945 return rc ? : copied;
949 * llc_ui_getname - return the address info of a socket
950 * @sock: Socket to get address of.
951 * @uaddr: Address structure to return information.
952 * @uaddrlen: Length of address structure.
953 * @peer: Does user want local or remote address information.
955 * Return the address information of a socket.
957 static int llc_ui_getname(struct socket *sock, struct sockaddr *uaddr,
958 int *uaddrlen, int peer)
960 struct sockaddr_llc sllc;
961 struct sock *sk = sock->sk;
962 struct llc_sock *llc = llc_sk(sk);
963 int rc = 0;
965 memset(&sllc, 0, sizeof(sllc));
966 lock_sock(sk);
967 if (sock_flag(sk, SOCK_ZAPPED))
968 goto out;
969 *uaddrlen = sizeof(sllc);
970 memset(uaddr, 0, *uaddrlen);
971 if (peer) {
972 rc = -ENOTCONN;
973 if (sk->sk_state != TCP_ESTABLISHED)
974 goto out;
975 if(llc->dev)
976 sllc.sllc_arphrd = llc->dev->type;
977 sllc.sllc_sap = llc->daddr.lsap;
978 memcpy(&sllc.sllc_mac, &llc->daddr.mac, IFHWADDRLEN);
979 } else {
980 rc = -EINVAL;
981 if (!llc->sap)
982 goto out;
983 sllc.sllc_sap = llc->sap->laddr.lsap;
985 if (llc->dev) {
986 sllc.sllc_arphrd = llc->dev->type;
987 memcpy(&sllc.sllc_mac, llc->dev->dev_addr,
988 IFHWADDRLEN);
991 rc = 0;
992 sllc.sllc_family = AF_LLC;
993 memcpy(uaddr, &sllc, sizeof(sllc));
994 out:
995 release_sock(sk);
996 return rc;
1000 * llc_ui_ioctl - io controls for PF_LLC
1001 * @sock: Socket to get/set info
1002 * @cmd: command
1003 * @arg: optional argument for cmd
1005 * get/set info on llc sockets
1007 static int llc_ui_ioctl(struct socket *sock, unsigned int cmd,
1008 unsigned long arg)
1010 return -ENOIOCTLCMD;
1014 * llc_ui_setsockopt - set various connection specific parameters.
1015 * @sock: Socket to set options on.
1016 * @level: Socket level user is requesting operations on.
1017 * @optname: Operation name.
1018 * @optval User provided operation data.
1019 * @optlen: Length of optval.
1021 * Set various connection specific parameters.
1023 static int llc_ui_setsockopt(struct socket *sock, int level, int optname,
1024 char __user *optval, unsigned int optlen)
1026 struct sock *sk = sock->sk;
1027 struct llc_sock *llc = llc_sk(sk);
1028 unsigned int opt;
1029 int rc = -EINVAL;
1031 lock_sock(sk);
1032 if (unlikely(level != SOL_LLC || optlen != sizeof(int)))
1033 goto out;
1034 rc = get_user(opt, (int __user *)optval);
1035 if (rc)
1036 goto out;
1037 rc = -EINVAL;
1038 switch (optname) {
1039 case LLC_OPT_RETRY:
1040 if (opt > LLC_OPT_MAX_RETRY)
1041 goto out;
1042 llc->n2 = opt;
1043 break;
1044 case LLC_OPT_SIZE:
1045 if (opt > LLC_OPT_MAX_SIZE)
1046 goto out;
1047 llc->n1 = opt;
1048 break;
1049 case LLC_OPT_ACK_TMR_EXP:
1050 if (opt > LLC_OPT_MAX_ACK_TMR_EXP)
1051 goto out;
1052 llc->ack_timer.expire = opt * HZ;
1053 break;
1054 case LLC_OPT_P_TMR_EXP:
1055 if (opt > LLC_OPT_MAX_P_TMR_EXP)
1056 goto out;
1057 llc->pf_cycle_timer.expire = opt * HZ;
1058 break;
1059 case LLC_OPT_REJ_TMR_EXP:
1060 if (opt > LLC_OPT_MAX_REJ_TMR_EXP)
1061 goto out;
1062 llc->rej_sent_timer.expire = opt * HZ;
1063 break;
1064 case LLC_OPT_BUSY_TMR_EXP:
1065 if (opt > LLC_OPT_MAX_BUSY_TMR_EXP)
1066 goto out;
1067 llc->busy_state_timer.expire = opt * HZ;
1068 break;
1069 case LLC_OPT_TX_WIN:
1070 if (opt > LLC_OPT_MAX_WIN)
1071 goto out;
1072 llc->k = opt;
1073 break;
1074 case LLC_OPT_RX_WIN:
1075 if (opt > LLC_OPT_MAX_WIN)
1076 goto out;
1077 llc->rw = opt;
1078 break;
1079 case LLC_OPT_PKTINFO:
1080 if (opt)
1081 llc->cmsg_flags |= LLC_CMSG_PKTINFO;
1082 else
1083 llc->cmsg_flags &= ~LLC_CMSG_PKTINFO;
1084 break;
1085 default:
1086 rc = -ENOPROTOOPT;
1087 goto out;
1089 rc = 0;
1090 out:
1091 release_sock(sk);
1092 return rc;
1096 * llc_ui_getsockopt - get connection specific socket info
1097 * @sock: Socket to get information from.
1098 * @level: Socket level user is requesting operations on.
1099 * @optname: Operation name.
1100 * @optval: Variable to return operation data in.
1101 * @optlen: Length of optval.
1103 * Get connection specific socket information.
1105 static int llc_ui_getsockopt(struct socket *sock, int level, int optname,
1106 char __user *optval, int __user *optlen)
1108 struct sock *sk = sock->sk;
1109 struct llc_sock *llc = llc_sk(sk);
1110 int val = 0, len = 0, rc = -EINVAL;
1112 lock_sock(sk);
1113 if (unlikely(level != SOL_LLC))
1114 goto out;
1115 rc = get_user(len, optlen);
1116 if (rc)
1117 goto out;
1118 rc = -EINVAL;
1119 if (len != sizeof(int))
1120 goto out;
1121 switch (optname) {
1122 case LLC_OPT_RETRY:
1123 val = llc->n2; break;
1124 case LLC_OPT_SIZE:
1125 val = llc->n1; break;
1126 case LLC_OPT_ACK_TMR_EXP:
1127 val = llc->ack_timer.expire / HZ; break;
1128 case LLC_OPT_P_TMR_EXP:
1129 val = llc->pf_cycle_timer.expire / HZ; break;
1130 case LLC_OPT_REJ_TMR_EXP:
1131 val = llc->rej_sent_timer.expire / HZ; break;
1132 case LLC_OPT_BUSY_TMR_EXP:
1133 val = llc->busy_state_timer.expire / HZ; break;
1134 case LLC_OPT_TX_WIN:
1135 val = llc->k; break;
1136 case LLC_OPT_RX_WIN:
1137 val = llc->rw; break;
1138 case LLC_OPT_PKTINFO:
1139 val = (llc->cmsg_flags & LLC_CMSG_PKTINFO) != 0;
1140 break;
1141 default:
1142 rc = -ENOPROTOOPT;
1143 goto out;
1145 rc = 0;
1146 if (put_user(len, optlen) || copy_to_user(optval, &val, len))
1147 rc = -EFAULT;
1148 out:
1149 release_sock(sk);
1150 return rc;
1153 static const struct net_proto_family llc_ui_family_ops = {
1154 .family = PF_LLC,
1155 .create = llc_ui_create,
1156 .owner = THIS_MODULE,
1159 static const struct proto_ops llc_ui_ops = {
1160 .family = PF_LLC,
1161 .owner = THIS_MODULE,
1162 .release = llc_ui_release,
1163 .bind = llc_ui_bind,
1164 .connect = llc_ui_connect,
1165 .socketpair = sock_no_socketpair,
1166 .accept = llc_ui_accept,
1167 .getname = llc_ui_getname,
1168 .poll = datagram_poll,
1169 .ioctl = llc_ui_ioctl,
1170 .listen = llc_ui_listen,
1171 .shutdown = llc_ui_shutdown,
1172 .setsockopt = llc_ui_setsockopt,
1173 .getsockopt = llc_ui_getsockopt,
1174 .sendmsg = llc_ui_sendmsg,
1175 .recvmsg = llc_ui_recvmsg,
1176 .mmap = sock_no_mmap,
1177 .sendpage = sock_no_sendpage,
1180 static const char llc_proc_err_msg[] __initconst =
1181 KERN_CRIT "LLC: Unable to register the proc_fs entries\n";
1182 static const char llc_sysctl_err_msg[] __initconst =
1183 KERN_CRIT "LLC: Unable to register the sysctl entries\n";
1184 static const char llc_sock_err_msg[] __initconst =
1185 KERN_CRIT "LLC: Unable to register the network family\n";
1187 static int __init llc2_init(void)
1189 int rc = proto_register(&llc_proto, 0);
1191 if (rc != 0)
1192 goto out;
1194 llc_build_offset_table();
1195 llc_station_init();
1196 llc_ui_sap_last_autoport = LLC_SAP_DYN_START;
1197 rc = llc_proc_init();
1198 if (rc != 0) {
1199 printk(llc_proc_err_msg);
1200 goto out_unregister_llc_proto;
1202 rc = llc_sysctl_init();
1203 if (rc) {
1204 printk(llc_sysctl_err_msg);
1205 goto out_proc;
1207 rc = sock_register(&llc_ui_family_ops);
1208 if (rc) {
1209 printk(llc_sock_err_msg);
1210 goto out_sysctl;
1212 llc_add_pack(LLC_DEST_SAP, llc_sap_handler);
1213 llc_add_pack(LLC_DEST_CONN, llc_conn_handler);
1214 out:
1215 return rc;
1216 out_sysctl:
1217 llc_sysctl_exit();
1218 out_proc:
1219 llc_proc_exit();
1220 out_unregister_llc_proto:
1221 proto_unregister(&llc_proto);
1222 goto out;
1225 static void __exit llc2_exit(void)
1227 llc_station_exit();
1228 llc_remove_pack(LLC_DEST_SAP);
1229 llc_remove_pack(LLC_DEST_CONN);
1230 sock_unregister(PF_LLC);
1231 llc_proc_exit();
1232 llc_sysctl_exit();
1233 proto_unregister(&llc_proto);
1236 module_init(llc2_init);
1237 module_exit(llc2_exit);
1239 MODULE_LICENSE("GPL");
1240 MODULE_AUTHOR("Procom 1997, Jay Schullist 2001, Arnaldo C. Melo 2001-2003");
1241 MODULE_DESCRIPTION("IEEE 802.2 PF_LLC support");
1242 MODULE_ALIAS_NETPROTO(PF_LLC);