Linux Audio

Check our new training course

Loading...
v6.2
   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 */
  38static u16 llc_ui_sap_last_autoport = LLC_SAP_DYN_START;
  39static u16 llc_ui_sap_link_no_max[256];
  40static struct sockaddr_llc llc_ui_addrnull;
  41static const struct proto_ops llc_ui_ops;
  42
  43static bool llc_ui_wait_for_conn(struct sock *sk, long timeout);
  44static int llc_ui_wait_for_disc(struct sock *sk, long timeout);
  45static int llc_ui_wait_for_busy_core(struct sock *sk, long timeout);
  46
  47#if 0
  48#define dprintk(args...) printk(KERN_DEBUG args)
  49#else
  50#define dprintk(args...) do {} while (0)
  51#endif
  52
  53/* Maybe we'll add some more in the future. */
  54#define LLC_CMSG_PKTINFO	1
  55
  56
  57/**
  58 *	llc_ui_next_link_no - return the next unused link number for a sap
  59 *	@sap: Address of sap to get link number from.
  60 *
  61 *	Return the next unused link number for a given sap.
  62 */
  63static 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 */
  74static 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 */
  83static 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 */
  97static inline u8 llc_ui_header_len(struct sock *sk, struct sockaddr_llc *addr)
  98{
  99	u8 rc = LLC_PDU_LEN_U;
 100
 101	if (addr->sllc_test)
 102		rc = LLC_PDU_LEN_U;
 103	else if (addr->sllc_xid)
 104		/* We need to expand header to sizeof(struct llc_xid_info)
 105		 * since llc_pdu_init_as_xid_cmd() sets 4,5,6 bytes of LLC header
 106		 * as XID PDU. In llc_ui_sendmsg() we reserved header size and then
 107		 * filled all other space with user data. If we won't reserve this
 108		 * bytes, llc_pdu_init_as_xid_cmd() will overwrite user data
 109		 */
 110		rc = LLC_PDU_LEN_U_XID;
 111	else if (sk->sk_type == SOCK_STREAM)
 112		rc = LLC_PDU_LEN_I;
 113	return rc;
 114}
 115
 116/**
 117 *	llc_ui_send_data - send data via reliable llc2 connection
 118 *	@sk: Connection the socket is using.
 119 *	@skb: Data the user wishes to send.
 120 *	@noblock: can we block waiting for data?
 121 *
 122 *	Send data via reliable llc2 connection.
 123 *	Returns 0 upon success, non-zero if action did not succeed.
 124 *
 125 *	This function always consumes a reference to the skb.
 126 */
 127static int llc_ui_send_data(struct sock* sk, struct sk_buff *skb, int noblock)
 128{
 129	struct llc_sock* llc = llc_sk(sk);
 130
 131	if (unlikely(llc_data_accept_state(llc->state) ||
 132		     llc->remote_busy_flag ||
 133		     llc->p_flag)) {
 134		long timeout = sock_sndtimeo(sk, noblock);
 135		int rc;
 136
 137		rc = llc_ui_wait_for_busy_core(sk, timeout);
 138		if (rc) {
 139			kfree_skb(skb);
 140			return rc;
 141		}
 142	}
 143	return llc_build_and_send_pkt(sk, skb);
 144}
 145
 146static void llc_ui_sk_init(struct socket *sock, struct sock *sk)
 147{
 148	sock_graft(sk, sock);
 149	sk->sk_type	= sock->type;
 150	sock->ops	= &llc_ui_ops;
 151}
 152
 153static struct proto llc_proto = {
 154	.name	  = "LLC",
 155	.owner	  = THIS_MODULE,
 156	.obj_size = sizeof(struct llc_sock),
 157	.slab_flags = SLAB_TYPESAFE_BY_RCU,
 158};
 159
 160/**
 161 *	llc_ui_create - alloc and init a new llc_ui socket
 162 *	@net: network namespace (must be default network)
 163 *	@sock: Socket to initialize and attach allocated sk to.
 164 *	@protocol: Unused.
 165 *	@kern: on behalf of kernel or userspace
 166 *
 167 *	Allocate and initialize a new llc_ui socket, validate the user wants a
 168 *	socket type we have available.
 169 *	Returns 0 upon success, negative upon failure.
 170 */
 171static int llc_ui_create(struct net *net, struct socket *sock, int protocol,
 172			 int kern)
 173{
 174	struct sock *sk;
 175	int rc = -ESOCKTNOSUPPORT;
 176
 177	if (!ns_capable(net->user_ns, CAP_NET_RAW))
 178		return -EPERM;
 179
 180	if (!net_eq(net, &init_net))
 181		return -EAFNOSUPPORT;
 182
 183	if (likely(sock->type == SOCK_DGRAM || sock->type == SOCK_STREAM)) {
 184		rc = -ENOMEM;
 185		sk = llc_sk_alloc(net, PF_LLC, GFP_KERNEL, &llc_proto, kern);
 186		if (sk) {
 187			rc = 0;
 188			llc_ui_sk_init(sock, sk);
 189		}
 190	}
 191	return rc;
 192}
 193
 194/**
 195 *	llc_ui_release - shutdown socket
 196 *	@sock: Socket to release.
 197 *
 198 *	Shutdown and deallocate an existing socket.
 199 */
 200static int llc_ui_release(struct socket *sock)
 201{
 202	struct sock *sk = sock->sk;
 203	struct llc_sock *llc;
 204
 205	if (unlikely(sk == NULL))
 206		goto out;
 207	sock_hold(sk);
 208	lock_sock(sk);
 209	llc = llc_sk(sk);
 210	dprintk("%s: closing local(%02X) remote(%02X)\n", __func__,
 211		llc->laddr.lsap, llc->daddr.lsap);
 212	if (!llc_send_disc(sk))
 213		llc_ui_wait_for_disc(sk, sk->sk_rcvtimeo);
 214	if (!sock_flag(sk, SOCK_ZAPPED)) {
 215		struct llc_sap *sap = llc->sap;
 216
 217		/* Hold this for release_sock(), so that llc_backlog_rcv()
 218		 * could still use it.
 219		 */
 220		llc_sap_hold(sap);
 221		llc_sap_remove_socket(llc->sap, sk);
 222		release_sock(sk);
 223		llc_sap_put(sap);
 224	} else {
 225		release_sock(sk);
 226	}
 227	netdev_put(llc->dev, &llc->dev_tracker);
 228	sock_put(sk);
 
 
 229	llc_sk_free(sk);
 230out:
 231	return 0;
 232}
 233
 234/**
 235 *	llc_ui_autoport - provide dynamically allocate SAP number
 236 *
 237 *	Provide the caller with a dynamically allocated SAP number according
 238 *	to the rules that are set in this function. Returns: 0, upon failure,
 239 *	SAP number otherwise.
 240 */
 241static int llc_ui_autoport(void)
 242{
 243	struct llc_sap *sap;
 244	int i, tries = 0;
 245
 246	while (tries < LLC_SAP_DYN_TRIES) {
 247		for (i = llc_ui_sap_last_autoport;
 248		     i < LLC_SAP_DYN_STOP; i += 2) {
 249			sap = llc_sap_find(i);
 250			if (!sap) {
 251				llc_ui_sap_last_autoport = i + 2;
 252				goto out;
 253			}
 254			llc_sap_put(sap);
 255		}
 256		llc_ui_sap_last_autoport = LLC_SAP_DYN_START;
 257		tries++;
 258	}
 259	i = 0;
 260out:
 261	return i;
 262}
 263
 264/**
 265 *	llc_ui_autobind - automatically bind a socket to a sap
 266 *	@sock: socket to bind
 267 *	@addr: address to connect to
 268 *
 269 * 	Used by llc_ui_connect and llc_ui_sendmsg when the user hasn't
 270 * 	specifically used llc_ui_bind to bind to an specific address/sap
 271 *
 272 *	Returns: 0 upon success, negative otherwise.
 273 */
 274static int llc_ui_autobind(struct socket *sock, struct sockaddr_llc *addr)
 275{
 276	struct sock *sk = sock->sk;
 277	struct llc_sock *llc = llc_sk(sk);
 278	struct net_device *dev = NULL;
 279	struct llc_sap *sap;
 280	int rc = -EINVAL;
 281
 282	if (!sock_flag(sk, SOCK_ZAPPED))
 283		goto out;
 284	if (!addr->sllc_arphrd)
 285		addr->sllc_arphrd = ARPHRD_ETHER;
 286	if (addr->sllc_arphrd != ARPHRD_ETHER)
 287		goto out;
 288	rc = -ENODEV;
 289	if (sk->sk_bound_dev_if) {
 290		dev = dev_get_by_index(&init_net, sk->sk_bound_dev_if);
 291		if (dev && addr->sllc_arphrd != dev->type) {
 292			dev_put(dev);
 293			dev = NULL;
 294		}
 295	} else
 296		dev = dev_getfirstbyhwtype(&init_net, addr->sllc_arphrd);
 297	if (!dev)
 298		goto out;
 299	rc = -EUSERS;
 300	llc->laddr.lsap = llc_ui_autoport();
 301	if (!llc->laddr.lsap)
 302		goto out;
 303	rc = -EBUSY; /* some other network layer is using the sap */
 304	sap = llc_sap_open(llc->laddr.lsap, NULL);
 305	if (!sap)
 306		goto out;
 307
 308	/* Note: We do not expect errors from this point. */
 309	llc->dev = dev;
 310	netdev_tracker_alloc(llc->dev, &llc->dev_tracker, GFP_KERNEL);
 311	dev = NULL;
 312
 313	memcpy(llc->laddr.mac, llc->dev->dev_addr, IFHWADDRLEN);
 314	memcpy(&llc->addr, addr, sizeof(llc->addr));
 315	/* assign new connection to its SAP */
 316	llc_sap_add_socket(sap, sk);
 317	sock_reset_flag(sk, SOCK_ZAPPED);
 318	rc = 0;
 319out:
 320	dev_put(dev);
 321	return rc;
 322}
 323
 324/**
 325 *	llc_ui_bind - bind a socket to a specific address.
 326 *	@sock: Socket to bind an address to.
 327 *	@uaddr: Address the user wants the socket bound to.
 328 *	@addrlen: Length of the uaddr structure.
 329 *
 330 *	Bind a socket to a specific address. For llc a user is able to bind to
 331 *	a specific sap only or mac + sap.
 332 *	If the user desires to bind to a specific mac + sap, it is possible to
 333 *	have multiple sap connections via multiple macs.
 334 *	Bind and autobind for that matter must enforce the correct sap usage
 335 *	otherwise all hell will break loose.
 336 *	Returns: 0 upon success, negative otherwise.
 337 */
 338static int llc_ui_bind(struct socket *sock, struct sockaddr *uaddr, int addrlen)
 339{
 340	struct sockaddr_llc *addr = (struct sockaddr_llc *)uaddr;
 341	struct sock *sk = sock->sk;
 342	struct llc_sock *llc = llc_sk(sk);
 343	struct net_device *dev = NULL;
 344	struct llc_sap *sap;
 345	int rc = -EINVAL;
 346
 347	lock_sock(sk);
 348	if (unlikely(!sock_flag(sk, SOCK_ZAPPED) || addrlen != sizeof(*addr)))
 349		goto out;
 350	rc = -EAFNOSUPPORT;
 351	if (!addr->sllc_arphrd)
 352		addr->sllc_arphrd = ARPHRD_ETHER;
 353	if (unlikely(addr->sllc_family != AF_LLC || addr->sllc_arphrd != ARPHRD_ETHER))
 354		goto out;
 355	dprintk("%s: binding %02X\n", __func__, addr->sllc_sap);
 356	rc = -ENODEV;
 357	rcu_read_lock();
 358	if (sk->sk_bound_dev_if) {
 359		dev = dev_get_by_index_rcu(&init_net, sk->sk_bound_dev_if);
 360		if (dev) {
 361			if (is_zero_ether_addr(addr->sllc_mac))
 362				memcpy(addr->sllc_mac, dev->dev_addr,
 363				       IFHWADDRLEN);
 364			if (addr->sllc_arphrd != dev->type ||
 365			    !ether_addr_equal(addr->sllc_mac,
 366					      dev->dev_addr)) {
 367				rc = -EINVAL;
 368				dev = NULL;
 369			}
 370		}
 371	} else {
 372		dev = dev_getbyhwaddr_rcu(&init_net, addr->sllc_arphrd,
 373					   addr->sllc_mac);
 374	}
 375	dev_hold(dev);
 376	rcu_read_unlock();
 377	if (!dev)
 378		goto out;
 379
 380	if (!addr->sllc_sap) {
 381		rc = -EUSERS;
 382		addr->sllc_sap = llc_ui_autoport();
 383		if (!addr->sllc_sap)
 384			goto out;
 385	}
 386	sap = llc_sap_find(addr->sllc_sap);
 387	if (!sap) {
 388		sap = llc_sap_open(addr->sllc_sap, NULL);
 389		rc = -EBUSY; /* some other network layer is using the sap */
 390		if (!sap)
 391			goto out;
 392	} else {
 393		struct llc_addr laddr, daddr;
 394		struct sock *ask;
 395
 396		memset(&laddr, 0, sizeof(laddr));
 397		memset(&daddr, 0, sizeof(daddr));
 398		/*
 399		 * FIXME: check if the address is multicast,
 400		 * 	  only SOCK_DGRAM can do this.
 401		 */
 402		memcpy(laddr.mac, addr->sllc_mac, IFHWADDRLEN);
 403		laddr.lsap = addr->sllc_sap;
 404		rc = -EADDRINUSE; /* mac + sap clash. */
 405		ask = llc_lookup_established(sap, &daddr, &laddr);
 406		if (ask) {
 407			sock_put(ask);
 408			goto out_put;
 409		}
 410	}
 411
 412	/* Note: We do not expect errors from this point. */
 413	llc->dev = dev;
 414	netdev_tracker_alloc(llc->dev, &llc->dev_tracker, GFP_KERNEL);
 415	dev = NULL;
 416
 417	llc->laddr.lsap = addr->sllc_sap;
 418	memcpy(llc->laddr.mac, addr->sllc_mac, IFHWADDRLEN);
 419	memcpy(&llc->addr, addr, sizeof(llc->addr));
 420	/* assign new connection to its SAP */
 421	llc_sap_add_socket(sap, sk);
 422	sock_reset_flag(sk, SOCK_ZAPPED);
 423	rc = 0;
 424out_put:
 425	llc_sap_put(sap);
 426out:
 427	dev_put(dev);
 428	release_sock(sk);
 429	return rc;
 430}
 431
 432/**
 433 *	llc_ui_shutdown - shutdown a connect llc2 socket.
 434 *	@sock: Socket to shutdown.
 435 *	@how: What part of the socket to shutdown.
 436 *
 437 *	Shutdown a connected llc2 socket. Currently this function only supports
 438 *	shutting down both sends and receives (2), we could probably make this
 439 *	function such that a user can shutdown only half the connection but not
 440 *	right now.
 441 *	Returns: 0 upon success, negative otherwise.
 442 */
 443static int llc_ui_shutdown(struct socket *sock, int how)
 444{
 445	struct sock *sk = sock->sk;
 446	int rc = -ENOTCONN;
 447
 448	lock_sock(sk);
 449	if (unlikely(sk->sk_state != TCP_ESTABLISHED))
 450		goto out;
 451	rc = -EINVAL;
 452	if (how != 2)
 453		goto out;
 454	rc = llc_send_disc(sk);
 455	if (!rc)
 456		rc = llc_ui_wait_for_disc(sk, sk->sk_rcvtimeo);
 457	/* Wake up anyone sleeping in poll */
 458	sk->sk_state_change(sk);
 459out:
 460	release_sock(sk);
 461	return rc;
 462}
 463
 464/**
 465 *	llc_ui_connect - Connect to a remote llc2 mac + sap.
 466 *	@sock: Socket which will be connected to the remote destination.
 467 *	@uaddr: Remote and possibly the local address of the new connection.
 468 *	@addrlen: Size of uaddr structure.
 469 *	@flags: Operational flags specified by the user.
 470 *
 471 *	Connect to a remote llc2 mac + sap. The caller must specify the
 472 *	destination mac and address to connect to. If the user hasn't previously
 473 *	called bind(2) with a smac the address of the first interface of the
 474 *	specified arp type will be used.
 475 *	This function will autobind if user did not previously call bind.
 476 *	Returns: 0 upon success, negative otherwise.
 477 */
 478static int llc_ui_connect(struct socket *sock, struct sockaddr *uaddr,
 479			  int addrlen, int flags)
 480{
 481	struct sock *sk = sock->sk;
 482	struct llc_sock *llc = llc_sk(sk);
 483	struct sockaddr_llc *addr = (struct sockaddr_llc *)uaddr;
 484	int rc = -EINVAL;
 485
 486	lock_sock(sk);
 487	if (unlikely(addrlen != sizeof(*addr)))
 488		goto out;
 489	rc = -EAFNOSUPPORT;
 490	if (unlikely(addr->sllc_family != AF_LLC))
 491		goto out;
 492	if (unlikely(sk->sk_type != SOCK_STREAM))
 493		goto out;
 494	rc = -EALREADY;
 495	if (unlikely(sock->state == SS_CONNECTING))
 496		goto out;
 497	/* bind connection to sap if user hasn't done it. */
 498	if (sock_flag(sk, SOCK_ZAPPED)) {
 499		/* bind to sap with null dev, exclusive */
 500		rc = llc_ui_autobind(sock, addr);
 501		if (rc)
 502			goto out;
 503	}
 504	llc->daddr.lsap = addr->sllc_sap;
 505	memcpy(llc->daddr.mac, addr->sllc_mac, IFHWADDRLEN);
 506	sock->state = SS_CONNECTING;
 507	sk->sk_state   = TCP_SYN_SENT;
 508	llc->link   = llc_ui_next_link_no(llc->sap->laddr.lsap);
 509	rc = llc_establish_connection(sk, llc->dev->dev_addr,
 510				      addr->sllc_mac, addr->sllc_sap);
 511	if (rc) {
 512		dprintk("%s: llc_ui_send_conn failed :-(\n", __func__);
 513		sock->state  = SS_UNCONNECTED;
 514		sk->sk_state = TCP_CLOSE;
 515		goto out;
 516	}
 517
 518	if (sk->sk_state == TCP_SYN_SENT) {
 519		const long timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
 520
 521		if (!timeo || !llc_ui_wait_for_conn(sk, timeo))
 522			goto out;
 523
 524		rc = sock_intr_errno(timeo);
 525		if (signal_pending(current))
 526			goto out;
 527	}
 528
 529	if (sk->sk_state == TCP_CLOSE)
 530		goto sock_error;
 531
 532	sock->state = SS_CONNECTED;
 533	rc = 0;
 534out:
 535	release_sock(sk);
 536	return rc;
 537sock_error:
 538	rc = sock_error(sk) ? : -ECONNABORTED;
 539	sock->state = SS_UNCONNECTED;
 540	goto out;
 541}
 542
 543/**
 544 *	llc_ui_listen - allow a normal socket to accept incoming connections
 545 *	@sock: Socket to allow incoming connections on.
 546 *	@backlog: Number of connections to queue.
 547 *
 548 *	Allow a normal socket to accept incoming connections.
 549 *	Returns 0 upon success, negative otherwise.
 550 */
 551static int llc_ui_listen(struct socket *sock, int backlog)
 552{
 553	struct sock *sk = sock->sk;
 554	int rc = -EINVAL;
 555
 556	lock_sock(sk);
 557	if (unlikely(sock->state != SS_UNCONNECTED))
 558		goto out;
 559	rc = -EOPNOTSUPP;
 560	if (unlikely(sk->sk_type != SOCK_STREAM))
 561		goto out;
 562	rc = -EAGAIN;
 563	if (sock_flag(sk, SOCK_ZAPPED))
 564		goto out;
 565	rc = 0;
 566	if (!(unsigned int)backlog)	/* BSDism */
 567		backlog = 1;
 568	sk->sk_max_ack_backlog = backlog;
 569	if (sk->sk_state != TCP_LISTEN) {
 570		sk->sk_ack_backlog = 0;
 571		sk->sk_state	   = TCP_LISTEN;
 572	}
 573	sk->sk_socket->flags |= __SO_ACCEPTCON;
 574out:
 575	release_sock(sk);
 576	return rc;
 577}
 578
 579static int llc_ui_wait_for_disc(struct sock *sk, long timeout)
 580{
 581	DEFINE_WAIT_FUNC(wait, woken_wake_function);
 582	int rc = 0;
 583
 584	add_wait_queue(sk_sleep(sk), &wait);
 585	while (1) {
 586		if (sk_wait_event(sk, &timeout, sk->sk_state == TCP_CLOSE, &wait))
 
 587			break;
 588		rc = -ERESTARTSYS;
 589		if (signal_pending(current))
 590			break;
 591		rc = -EAGAIN;
 592		if (!timeout)
 593			break;
 594		rc = 0;
 595	}
 596	remove_wait_queue(sk_sleep(sk), &wait);
 597	return rc;
 598}
 599
 600static bool llc_ui_wait_for_conn(struct sock *sk, long timeout)
 601{
 602	DEFINE_WAIT_FUNC(wait, woken_wake_function);
 603
 604	add_wait_queue(sk_sleep(sk), &wait);
 605	while (1) {
 606		if (sk_wait_event(sk, &timeout, sk->sk_state != TCP_SYN_SENT, &wait))
 
 607			break;
 608		if (signal_pending(current) || !timeout)
 609			break;
 610	}
 611	remove_wait_queue(sk_sleep(sk), &wait);
 612	return timeout;
 613}
 614
 615static int llc_ui_wait_for_busy_core(struct sock *sk, long timeout)
 616{
 617	DEFINE_WAIT_FUNC(wait, woken_wake_function);
 618	struct llc_sock *llc = llc_sk(sk);
 619	int rc;
 620
 621	add_wait_queue(sk_sleep(sk), &wait);
 622	while (1) {
 623		rc = 0;
 624		if (sk_wait_event(sk, &timeout,
 625				  (sk->sk_shutdown & RCV_SHUTDOWN) ||
 626				  (!llc_data_accept_state(llc->state) &&
 627				   !llc->remote_busy_flag &&
 628				   !llc->p_flag), &wait))
 629			break;
 630		rc = -ERESTARTSYS;
 631		if (signal_pending(current))
 632			break;
 633		rc = -EAGAIN;
 634		if (!timeout)
 635			break;
 636	}
 637	remove_wait_queue(sk_sleep(sk), &wait);
 638	return rc;
 639}
 640
 641static int llc_wait_data(struct sock *sk, long timeo)
 642{
 643	int rc;
 644
 645	while (1) {
 646		/*
 647		 * POSIX 1003.1g mandates this order.
 648		 */
 649		rc = sock_error(sk);
 650		if (rc)
 651			break;
 652		rc = 0;
 653		if (sk->sk_shutdown & RCV_SHUTDOWN)
 654			break;
 655		rc = -EAGAIN;
 656		if (!timeo)
 657			break;
 658		rc = sock_intr_errno(timeo);
 659		if (signal_pending(current))
 660			break;
 661		rc = 0;
 662		if (sk_wait_data(sk, &timeo, NULL))
 663			break;
 664	}
 665	return rc;
 666}
 667
 668static void llc_cmsg_rcv(struct msghdr *msg, struct sk_buff *skb)
 669{
 670	struct llc_sock *llc = llc_sk(skb->sk);
 671
 672	if (llc->cmsg_flags & LLC_CMSG_PKTINFO) {
 673		struct llc_pktinfo info;
 674
 675		memset(&info, 0, sizeof(info));
 676		info.lpi_ifindex = llc_sk(skb->sk)->dev->ifindex;
 677		llc_pdu_decode_dsap(skb, &info.lpi_sap);
 678		llc_pdu_decode_da(skb, info.lpi_mac);
 679		put_cmsg(msg, SOL_LLC, LLC_OPT_PKTINFO, sizeof(info), &info);
 680	}
 681}
 682
 683/**
 684 *	llc_ui_accept - accept a new incoming connection.
 685 *	@sock: Socket which connections arrive on.
 686 *	@newsock: Socket to move incoming connection to.
 687 *	@flags: User specified operational flags.
 688 *	@kern: If the socket is kernel internal
 689 *
 690 *	Accept a new incoming connection.
 691 *	Returns 0 upon success, negative otherwise.
 692 */
 693static int llc_ui_accept(struct socket *sock, struct socket *newsock, int flags,
 694			 bool kern)
 695{
 696	struct sock *sk = sock->sk, *newsk;
 697	struct llc_sock *llc, *newllc;
 698	struct sk_buff *skb;
 699	int rc = -EOPNOTSUPP;
 700
 701	dprintk("%s: accepting on %02X\n", __func__,
 702		llc_sk(sk)->laddr.lsap);
 703	lock_sock(sk);
 704	if (unlikely(sk->sk_type != SOCK_STREAM))
 705		goto out;
 706	rc = -EINVAL;
 707	if (unlikely(sock->state != SS_UNCONNECTED ||
 708		     sk->sk_state != TCP_LISTEN))
 709		goto out;
 710	/* wait for a connection to arrive. */
 711	if (skb_queue_empty(&sk->sk_receive_queue)) {
 712		rc = llc_wait_data(sk, sk->sk_rcvtimeo);
 713		if (rc)
 714			goto out;
 715	}
 716	dprintk("%s: got a new connection on %02X\n", __func__,
 717		llc_sk(sk)->laddr.lsap);
 718	skb = skb_dequeue(&sk->sk_receive_queue);
 719	rc = -EINVAL;
 720	if (!skb->sk)
 721		goto frees;
 722	rc = 0;
 723	newsk = skb->sk;
 724	/* attach connection to a new socket. */
 725	llc_ui_sk_init(newsock, newsk);
 726	sock_reset_flag(newsk, SOCK_ZAPPED);
 727	newsk->sk_state		= TCP_ESTABLISHED;
 728	newsock->state		= SS_CONNECTED;
 729	llc			= llc_sk(sk);
 730	newllc			= llc_sk(newsk);
 731	memcpy(&newllc->addr, &llc->addr, sizeof(newllc->addr));
 732	newllc->link = llc_ui_next_link_no(newllc->laddr.lsap);
 733
 734	/* put original socket back into a clean listen state. */
 735	sk->sk_state = TCP_LISTEN;
 736	sk_acceptq_removed(sk);
 737	dprintk("%s: ok success on %02X, client on %02X\n", __func__,
 738		llc_sk(sk)->addr.sllc_sap, newllc->daddr.lsap);
 739frees:
 740	kfree_skb(skb);
 741out:
 742	release_sock(sk);
 743	return rc;
 744}
 745
 746/**
 747 *	llc_ui_recvmsg - copy received data to the socket user.
 748 *	@sock: Socket to copy data from.
 749 *	@msg: Various user space related information.
 750 *	@len: Size of user buffer.
 751 *	@flags: User specified flags.
 752 *
 753 *	Copy received data to the socket user.
 754 *	Returns non-negative upon success, negative otherwise.
 755 */
 756static int llc_ui_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
 757			  int flags)
 758{
 759	DECLARE_SOCKADDR(struct sockaddr_llc *, uaddr, msg->msg_name);
 760	const int nonblock = flags & MSG_DONTWAIT;
 761	struct sk_buff *skb = NULL;
 762	struct sock *sk = sock->sk;
 763	struct llc_sock *llc = llc_sk(sk);
 764	size_t copied = 0;
 765	u32 peek_seq = 0;
 766	u32 *seq, skb_len;
 767	unsigned long used;
 768	int target;	/* Read at least this many bytes */
 769	long timeo;
 770
 771	lock_sock(sk);
 772	copied = -ENOTCONN;
 773	if (unlikely(sk->sk_type == SOCK_STREAM && sk->sk_state == TCP_LISTEN))
 774		goto out;
 775
 776	timeo = sock_rcvtimeo(sk, nonblock);
 777
 778	seq = &llc->copied_seq;
 779	if (flags & MSG_PEEK) {
 780		peek_seq = llc->copied_seq;
 781		seq = &peek_seq;
 782	}
 783
 784	target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
 785	copied = 0;
 786
 787	do {
 788		u32 offset;
 789
 790		/*
 791		 * We need to check signals first, to get correct SIGURG
 792		 * handling. FIXME: Need to check this doesn't impact 1003.1g
 793		 * and move it down to the bottom of the loop
 794		 */
 795		if (signal_pending(current)) {
 796			if (copied)
 797				break;
 798			copied = timeo ? sock_intr_errno(timeo) : -EAGAIN;
 799			break;
 800		}
 801
 802		/* Next get a buffer. */
 803
 804		skb = skb_peek(&sk->sk_receive_queue);
 805		if (skb) {
 806			offset = *seq;
 807			goto found_ok_skb;
 808		}
 809		/* Well, if we have backlog, try to process it now yet. */
 810
 811		if (copied >= target && !READ_ONCE(sk->sk_backlog.tail))
 812			break;
 813
 814		if (copied) {
 815			if (sk->sk_err ||
 816			    sk->sk_state == TCP_CLOSE ||
 817			    (sk->sk_shutdown & RCV_SHUTDOWN) ||
 818			    !timeo ||
 819			    (flags & MSG_PEEK))
 820				break;
 821		} else {
 822			if (sock_flag(sk, SOCK_DONE))
 823				break;
 824
 825			if (sk->sk_err) {
 826				copied = sock_error(sk);
 827				break;
 828			}
 829			if (sk->sk_shutdown & RCV_SHUTDOWN)
 830				break;
 831
 832			if (sk->sk_type == SOCK_STREAM && sk->sk_state == TCP_CLOSE) {
 833				if (!sock_flag(sk, SOCK_DONE)) {
 834					/*
 835					 * This occurs when user tries to read
 836					 * from never connected socket.
 837					 */
 838					copied = -ENOTCONN;
 839					break;
 840				}
 841				break;
 842			}
 843			if (!timeo) {
 844				copied = -EAGAIN;
 845				break;
 846			}
 847		}
 848
 849		if (copied >= target) { /* Do not sleep, just process backlog. */
 850			release_sock(sk);
 851			lock_sock(sk);
 852		} else
 853			sk_wait_data(sk, &timeo, NULL);
 854
 855		if ((flags & MSG_PEEK) && peek_seq != llc->copied_seq) {
 856			net_dbg_ratelimited("LLC(%s:%d): Application bug, race in MSG_PEEK\n",
 857					    current->comm,
 858					    task_pid_nr(current));
 859			peek_seq = llc->copied_seq;
 860		}
 861		continue;
 862	found_ok_skb:
 863		skb_len = skb->len;
 864		/* Ok so how much can we use? */
 865		used = skb->len - offset;
 866		if (len < used)
 867			used = len;
 868
 869		if (!(flags & MSG_TRUNC)) {
 870			int rc = skb_copy_datagram_msg(skb, offset, msg, used);
 871			if (rc) {
 872				/* Exception. Bailout! */
 873				if (!copied)
 874					copied = -EFAULT;
 875				break;
 876			}
 877		}
 878
 879		*seq += used;
 880		copied += used;
 881		len -= used;
 882
 883		/* For non stream protcols we get one packet per recvmsg call */
 884		if (sk->sk_type != SOCK_STREAM)
 885			goto copy_uaddr;
 886
 887		if (!(flags & MSG_PEEK)) {
 888			skb_unlink(skb, &sk->sk_receive_queue);
 889			kfree_skb(skb);
 890			*seq = 0;
 891		}
 892
 893		/* Partial read */
 894		if (used + offset < skb_len)
 895			continue;
 896	} while (len > 0);
 897
 898out:
 899	release_sock(sk);
 900	return copied;
 901copy_uaddr:
 902	if (uaddr != NULL && skb != NULL) {
 903		memcpy(uaddr, llc_ui_skb_cb(skb), sizeof(*uaddr));
 904		msg->msg_namelen = sizeof(*uaddr);
 905	}
 906	if (llc_sk(sk)->cmsg_flags)
 907		llc_cmsg_rcv(msg, skb);
 908
 909	if (!(flags & MSG_PEEK)) {
 910		skb_unlink(skb, &sk->sk_receive_queue);
 911		kfree_skb(skb);
 912		*seq = 0;
 913	}
 914
 915	goto out;
 916}
 917
 918/**
 919 *	llc_ui_sendmsg - Transmit data provided by the socket user.
 920 *	@sock: Socket to transmit data from.
 921 *	@msg: Various user related information.
 922 *	@len: Length of data to transmit.
 923 *
 924 *	Transmit data provided by the socket user.
 925 *	Returns non-negative upon success, negative otherwise.
 926 */
 927static int llc_ui_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
 928{
 
 929	struct sock *sk = sock->sk;
 930	struct llc_sock *llc = llc_sk(sk);
 931	DECLARE_SOCKADDR(struct sockaddr_llc *, addr, msg->msg_name);
 932	int flags = msg->msg_flags;
 933	int noblock = flags & MSG_DONTWAIT;
 
 934	struct sk_buff *skb = NULL;
 
 935	size_t size = 0;
 936	int rc = -EINVAL, copied = 0, hdrlen;
 937
 938	dprintk("%s: sending from %02X to %02X\n", __func__,
 939		llc->laddr.lsap, llc->daddr.lsap);
 940	lock_sock(sk);
 941	if (addr) {
 942		if (msg->msg_namelen < sizeof(*addr))
 943			goto out;
 944	} else {
 945		if (llc_ui_addr_null(&llc->addr))
 946			goto out;
 947		addr = &llc->addr;
 948	}
 949	/* must bind connection to sap if user hasn't done it. */
 950	if (sock_flag(sk, SOCK_ZAPPED)) {
 951		/* bind to sap with null dev, exclusive. */
 952		rc = llc_ui_autobind(sock, addr);
 953		if (rc)
 954			goto out;
 955	}
 956	hdrlen = llc->dev->hard_header_len + llc_ui_header_len(sk, addr);
 
 
 957	size = hdrlen + len;
 958	if (size > llc->dev->mtu)
 959		size = llc->dev->mtu;
 960	copied = size - hdrlen;
 961	rc = -EINVAL;
 962	if (copied < 0)
 963		goto out;
 964	release_sock(sk);
 965	skb = sock_alloc_send_skb(sk, size, noblock, &rc);
 966	lock_sock(sk);
 967	if (!skb)
 968		goto out;
 969	skb->dev      = llc->dev;
 
 
 
 
 
 
 970	skb->protocol = llc_proto_type(addr->sllc_arphrd);
 971	skb_reserve(skb, hdrlen);
 972	rc = memcpy_from_msg(skb_put(skb, copied), msg, copied);
 973	if (rc)
 974		goto out;
 975	if (sk->sk_type == SOCK_DGRAM || addr->sllc_ua) {
 976		llc_build_and_send_ui_pkt(llc->sap, skb, addr->sllc_mac,
 977					  addr->sllc_sap);
 978		skb = NULL;
 979		goto out;
 980	}
 981	if (addr->sllc_test) {
 982		llc_build_and_send_test_pkt(llc->sap, skb, addr->sllc_mac,
 983					    addr->sllc_sap);
 984		skb = NULL;
 985		goto out;
 986	}
 987	if (addr->sllc_xid) {
 988		llc_build_and_send_xid_pkt(llc->sap, skb, addr->sllc_mac,
 989					   addr->sllc_sap);
 990		skb = NULL;
 991		goto out;
 992	}
 993	rc = -ENOPROTOOPT;
 994	if (!(sk->sk_type == SOCK_STREAM && !addr->sllc_ua))
 995		goto out;
 996	rc = llc_ui_send_data(sk, skb, noblock);
 997	skb = NULL;
 998out:
 999	kfree_skb(skb);
1000	if (rc)
1001		dprintk("%s: failed sending from %02X to %02X: %d\n",
1002			__func__, llc->laddr.lsap, llc->daddr.lsap, rc);
1003	release_sock(sk);
1004	return rc ? : copied;
1005}
1006
1007/**
1008 *	llc_ui_getname - return the address info of a socket
1009 *	@sock: Socket to get address of.
1010 *	@uaddr: Address structure to return information.
1011 *	@peer: Does user want local or remote address information.
1012 *
1013 *	Return the address information of a socket.
1014 */
1015static int llc_ui_getname(struct socket *sock, struct sockaddr *uaddr,
1016			  int peer)
1017{
1018	struct sockaddr_llc sllc;
1019	struct sock *sk = sock->sk;
1020	struct llc_sock *llc = llc_sk(sk);
1021	int rc = -EBADF;
1022
1023	memset(&sllc, 0, sizeof(sllc));
1024	lock_sock(sk);
1025	if (sock_flag(sk, SOCK_ZAPPED))
1026		goto out;
1027	if (peer) {
1028		rc = -ENOTCONN;
1029		if (sk->sk_state != TCP_ESTABLISHED)
1030			goto out;
1031		if(llc->dev)
1032			sllc.sllc_arphrd = llc->dev->type;
1033		sllc.sllc_sap = llc->daddr.lsap;
1034		memcpy(&sllc.sllc_mac, &llc->daddr.mac, IFHWADDRLEN);
1035	} else {
1036		rc = -EINVAL;
1037		if (!llc->sap)
1038			goto out;
1039		sllc.sllc_sap = llc->sap->laddr.lsap;
1040
1041		if (llc->dev) {
1042			sllc.sllc_arphrd = llc->dev->type;
1043			memcpy(&sllc.sllc_mac, llc->dev->dev_addr,
1044			       IFHWADDRLEN);
1045		}
1046	}
1047	sllc.sllc_family = AF_LLC;
1048	memcpy(uaddr, &sllc, sizeof(sllc));
1049	rc = sizeof(sllc);
1050out:
1051	release_sock(sk);
1052	return rc;
1053}
1054
1055/**
1056 *	llc_ui_ioctl - io controls for PF_LLC
1057 *	@sock: Socket to get/set info
1058 *	@cmd: command
1059 *	@arg: optional argument for cmd
1060 *
1061 *	get/set info on llc sockets
1062 */
1063static int llc_ui_ioctl(struct socket *sock, unsigned int cmd,
1064			unsigned long arg)
1065{
1066	return -ENOIOCTLCMD;
1067}
1068
1069/**
1070 *	llc_ui_setsockopt - set various connection specific parameters.
1071 *	@sock: Socket to set options on.
1072 *	@level: Socket level user is requesting operations on.
1073 *	@optname: Operation name.
1074 *	@optval: User provided operation data.
1075 *	@optlen: Length of optval.
1076 *
1077 *	Set various connection specific parameters.
1078 */
1079static int llc_ui_setsockopt(struct socket *sock, int level, int optname,
1080			     sockptr_t optval, unsigned int optlen)
1081{
1082	struct sock *sk = sock->sk;
1083	struct llc_sock *llc = llc_sk(sk);
1084	unsigned int opt;
1085	int rc = -EINVAL;
1086
1087	lock_sock(sk);
1088	if (unlikely(level != SOL_LLC || optlen != sizeof(int)))
1089		goto out;
1090	rc = copy_from_sockptr(&opt, optval, sizeof(opt));
1091	if (rc)
1092		goto out;
1093	rc = -EINVAL;
1094	switch (optname) {
1095	case LLC_OPT_RETRY:
1096		if (opt > LLC_OPT_MAX_RETRY)
1097			goto out;
1098		llc->n2 = opt;
1099		break;
1100	case LLC_OPT_SIZE:
1101		if (opt > LLC_OPT_MAX_SIZE)
1102			goto out;
1103		llc->n1 = opt;
1104		break;
1105	case LLC_OPT_ACK_TMR_EXP:
1106		if (opt > LLC_OPT_MAX_ACK_TMR_EXP)
1107			goto out;
1108		llc->ack_timer.expire = opt * HZ;
1109		break;
1110	case LLC_OPT_P_TMR_EXP:
1111		if (opt > LLC_OPT_MAX_P_TMR_EXP)
1112			goto out;
1113		llc->pf_cycle_timer.expire = opt * HZ;
1114		break;
1115	case LLC_OPT_REJ_TMR_EXP:
1116		if (opt > LLC_OPT_MAX_REJ_TMR_EXP)
1117			goto out;
1118		llc->rej_sent_timer.expire = opt * HZ;
1119		break;
1120	case LLC_OPT_BUSY_TMR_EXP:
1121		if (opt > LLC_OPT_MAX_BUSY_TMR_EXP)
1122			goto out;
1123		llc->busy_state_timer.expire = opt * HZ;
1124		break;
1125	case LLC_OPT_TX_WIN:
1126		if (opt > LLC_OPT_MAX_WIN)
1127			goto out;
1128		llc->k = opt;
1129		break;
1130	case LLC_OPT_RX_WIN:
1131		if (opt > LLC_OPT_MAX_WIN)
1132			goto out;
1133		llc->rw = opt;
1134		break;
1135	case LLC_OPT_PKTINFO:
1136		if (opt)
1137			llc->cmsg_flags |= LLC_CMSG_PKTINFO;
1138		else
1139			llc->cmsg_flags &= ~LLC_CMSG_PKTINFO;
1140		break;
1141	default:
1142		rc = -ENOPROTOOPT;
1143		goto out;
1144	}
1145	rc = 0;
1146out:
1147	release_sock(sk);
1148	return rc;
1149}
1150
1151/**
1152 *	llc_ui_getsockopt - get connection specific socket info
1153 *	@sock: Socket to get information from.
1154 *	@level: Socket level user is requesting operations on.
1155 *	@optname: Operation name.
1156 *	@optval: Variable to return operation data in.
1157 *	@optlen: Length of optval.
1158 *
1159 *	Get connection specific socket information.
1160 */
1161static int llc_ui_getsockopt(struct socket *sock, int level, int optname,
1162			     char __user *optval, int __user *optlen)
1163{
1164	struct sock *sk = sock->sk;
1165	struct llc_sock *llc = llc_sk(sk);
1166	int val = 0, len = 0, rc = -EINVAL;
1167
1168	lock_sock(sk);
1169	if (unlikely(level != SOL_LLC))
1170		goto out;
1171	rc = get_user(len, optlen);
1172	if (rc)
1173		goto out;
1174	rc = -EINVAL;
1175	if (len != sizeof(int))
1176		goto out;
1177	switch (optname) {
1178	case LLC_OPT_RETRY:
1179		val = llc->n2;					break;
1180	case LLC_OPT_SIZE:
1181		val = llc->n1;					break;
1182	case LLC_OPT_ACK_TMR_EXP:
1183		val = llc->ack_timer.expire / HZ;		break;
1184	case LLC_OPT_P_TMR_EXP:
1185		val = llc->pf_cycle_timer.expire / HZ;		break;
1186	case LLC_OPT_REJ_TMR_EXP:
1187		val = llc->rej_sent_timer.expire / HZ;		break;
1188	case LLC_OPT_BUSY_TMR_EXP:
1189		val = llc->busy_state_timer.expire / HZ;	break;
1190	case LLC_OPT_TX_WIN:
1191		val = llc->k;				break;
1192	case LLC_OPT_RX_WIN:
1193		val = llc->rw;				break;
1194	case LLC_OPT_PKTINFO:
1195		val = (llc->cmsg_flags & LLC_CMSG_PKTINFO) != 0;
1196		break;
1197	default:
1198		rc = -ENOPROTOOPT;
1199		goto out;
1200	}
1201	rc = 0;
1202	if (put_user(len, optlen) || copy_to_user(optval, &val, len))
1203		rc = -EFAULT;
1204out:
1205	release_sock(sk);
1206	return rc;
1207}
1208
1209static const struct net_proto_family llc_ui_family_ops = {
1210	.family = PF_LLC,
1211	.create = llc_ui_create,
1212	.owner	= THIS_MODULE,
1213};
1214
1215static const struct proto_ops llc_ui_ops = {
1216	.family	     = PF_LLC,
1217	.owner       = THIS_MODULE,
1218	.release     = llc_ui_release,
1219	.bind	     = llc_ui_bind,
1220	.connect     = llc_ui_connect,
1221	.socketpair  = sock_no_socketpair,
1222	.accept      = llc_ui_accept,
1223	.getname     = llc_ui_getname,
1224	.poll	     = datagram_poll,
1225	.ioctl       = llc_ui_ioctl,
1226	.listen      = llc_ui_listen,
1227	.shutdown    = llc_ui_shutdown,
1228	.setsockopt  = llc_ui_setsockopt,
1229	.getsockopt  = llc_ui_getsockopt,
1230	.sendmsg     = llc_ui_sendmsg,
1231	.recvmsg     = llc_ui_recvmsg,
1232	.mmap	     = sock_no_mmap,
1233	.sendpage    = sock_no_sendpage,
1234};
1235
1236static const char llc_proc_err_msg[] __initconst =
1237	KERN_CRIT "LLC: Unable to register the proc_fs entries\n";
1238static const char llc_sysctl_err_msg[] __initconst =
1239	KERN_CRIT "LLC: Unable to register the sysctl entries\n";
1240static const char llc_sock_err_msg[] __initconst =
1241	KERN_CRIT "LLC: Unable to register the network family\n";
1242
1243static int __init llc2_init(void)
1244{
1245	int rc = proto_register(&llc_proto, 0);
1246
1247	if (rc != 0)
1248		goto out;
1249
1250	llc_build_offset_table();
1251	llc_station_init();
1252	llc_ui_sap_last_autoport = LLC_SAP_DYN_START;
1253	rc = llc_proc_init();
1254	if (rc != 0) {
1255		printk(llc_proc_err_msg);
1256		goto out_station;
1257	}
1258	rc = llc_sysctl_init();
1259	if (rc) {
1260		printk(llc_sysctl_err_msg);
1261		goto out_proc;
1262	}
1263	rc = sock_register(&llc_ui_family_ops);
1264	if (rc) {
1265		printk(llc_sock_err_msg);
1266		goto out_sysctl;
1267	}
1268	llc_add_pack(LLC_DEST_SAP, llc_sap_handler);
1269	llc_add_pack(LLC_DEST_CONN, llc_conn_handler);
1270out:
1271	return rc;
1272out_sysctl:
1273	llc_sysctl_exit();
1274out_proc:
1275	llc_proc_exit();
1276out_station:
1277	llc_station_exit();
1278	proto_unregister(&llc_proto);
1279	goto out;
1280}
1281
1282static void __exit llc2_exit(void)
1283{
1284	llc_station_exit();
1285	llc_remove_pack(LLC_DEST_SAP);
1286	llc_remove_pack(LLC_DEST_CONN);
1287	sock_unregister(PF_LLC);
1288	llc_proc_exit();
1289	llc_sysctl_exit();
1290	proto_unregister(&llc_proto);
1291}
1292
1293module_init(llc2_init);
1294module_exit(llc2_exit);
1295
1296MODULE_LICENSE("GPL");
1297MODULE_AUTHOR("Procom 1997, Jay Schullist 2001, Arnaldo C. Melo 2001-2003");
1298MODULE_DESCRIPTION("IEEE 802.2 PF_LLC support");
1299MODULE_ALIAS_NETPROTO(PF_LLC);
v6.13.7
   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 */
  38static u16 llc_ui_sap_last_autoport = LLC_SAP_DYN_START;
  39static u16 llc_ui_sap_link_no_max[256];
  40static struct sockaddr_llc llc_ui_addrnull;
  41static const struct proto_ops llc_ui_ops;
  42
  43static bool llc_ui_wait_for_conn(struct sock *sk, long timeout);
  44static int llc_ui_wait_for_disc(struct sock *sk, long timeout);
  45static int llc_ui_wait_for_busy_core(struct sock *sk, long timeout);
  46
  47#if 0
  48#define dprintk(args...) printk(KERN_DEBUG args)
  49#else
  50#define dprintk(args...) do {} while (0)
  51#endif
  52
  53/* Maybe we'll add some more in the future. */
  54#define LLC_CMSG_PKTINFO	1
  55
  56
  57/**
  58 *	llc_ui_next_link_no - return the next unused link number for a sap
  59 *	@sap: Address of sap to get link number from.
  60 *
  61 *	Return the next unused link number for a given sap.
  62 */
  63static 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 */
  74static 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 */
  83static 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 */
  97static inline u8 llc_ui_header_len(struct sock *sk, struct sockaddr_llc *addr)
  98{
  99	u8 rc = LLC_PDU_LEN_U;
 100
 101	if (addr->sllc_test)
 102		rc = LLC_PDU_LEN_U;
 103	else if (addr->sllc_xid)
 104		/* We need to expand header to sizeof(struct llc_xid_info)
 105		 * since llc_pdu_init_as_xid_cmd() sets 4,5,6 bytes of LLC header
 106		 * as XID PDU. In llc_ui_sendmsg() we reserved header size and then
 107		 * filled all other space with user data. If we won't reserve this
 108		 * bytes, llc_pdu_init_as_xid_cmd() will overwrite user data
 109		 */
 110		rc = LLC_PDU_LEN_U_XID;
 111	else if (sk->sk_type == SOCK_STREAM)
 112		rc = LLC_PDU_LEN_I;
 113	return rc;
 114}
 115
 116/**
 117 *	llc_ui_send_data - send data via reliable llc2 connection
 118 *	@sk: Connection the socket is using.
 119 *	@skb: Data the user wishes to send.
 120 *	@noblock: can we block waiting for data?
 121 *
 122 *	Send data via reliable llc2 connection.
 123 *	Returns 0 upon success, non-zero if action did not succeed.
 124 *
 125 *	This function always consumes a reference to the skb.
 126 */
 127static int llc_ui_send_data(struct sock* sk, struct sk_buff *skb, int noblock)
 128{
 129	struct llc_sock* llc = llc_sk(sk);
 130
 131	if (unlikely(llc_data_accept_state(llc->state) ||
 132		     llc->remote_busy_flag ||
 133		     llc->p_flag)) {
 134		long timeout = sock_sndtimeo(sk, noblock);
 135		int rc;
 136
 137		rc = llc_ui_wait_for_busy_core(sk, timeout);
 138		if (rc) {
 139			kfree_skb(skb);
 140			return rc;
 141		}
 142	}
 143	return llc_build_and_send_pkt(sk, skb);
 144}
 145
 146static void llc_ui_sk_init(struct socket *sock, struct sock *sk)
 147{
 148	sock_graft(sk, sock);
 149	sk->sk_type	= sock->type;
 150	sock->ops	= &llc_ui_ops;
 151}
 152
 153static struct proto llc_proto = {
 154	.name	  = "LLC",
 155	.owner	  = THIS_MODULE,
 156	.obj_size = sizeof(struct llc_sock),
 157	.slab_flags = SLAB_TYPESAFE_BY_RCU,
 158};
 159
 160/**
 161 *	llc_ui_create - alloc and init a new llc_ui socket
 162 *	@net: network namespace (must be default network)
 163 *	@sock: Socket to initialize and attach allocated sk to.
 164 *	@protocol: Unused.
 165 *	@kern: on behalf of kernel or userspace
 166 *
 167 *	Allocate and initialize a new llc_ui socket, validate the user wants a
 168 *	socket type we have available.
 169 *	Returns 0 upon success, negative upon failure.
 170 */
 171static int llc_ui_create(struct net *net, struct socket *sock, int protocol,
 172			 int kern)
 173{
 174	struct sock *sk;
 175	int rc = -ESOCKTNOSUPPORT;
 176
 177	if (!ns_capable(net->user_ns, CAP_NET_RAW))
 178		return -EPERM;
 179
 180	if (!net_eq(net, &init_net))
 181		return -EAFNOSUPPORT;
 182
 183	if (likely(sock->type == SOCK_DGRAM || sock->type == SOCK_STREAM)) {
 184		rc = -ENOMEM;
 185		sk = llc_sk_alloc(net, PF_LLC, GFP_KERNEL, &llc_proto, kern);
 186		if (sk) {
 187			rc = 0;
 188			llc_ui_sk_init(sock, sk);
 189		}
 190	}
 191	return rc;
 192}
 193
 194/**
 195 *	llc_ui_release - shutdown socket
 196 *	@sock: Socket to release.
 197 *
 198 *	Shutdown and deallocate an existing socket.
 199 */
 200static int llc_ui_release(struct socket *sock)
 201{
 202	struct sock *sk = sock->sk;
 203	struct llc_sock *llc;
 204
 205	if (unlikely(sk == NULL))
 206		goto out;
 207	sock_hold(sk);
 208	lock_sock(sk);
 209	llc = llc_sk(sk);
 210	dprintk("%s: closing local(%02X) remote(%02X)\n", __func__,
 211		llc->laddr.lsap, llc->daddr.lsap);
 212	if (!llc_send_disc(sk))
 213		llc_ui_wait_for_disc(sk, sk->sk_rcvtimeo);
 214	if (!sock_flag(sk, SOCK_ZAPPED)) {
 215		struct llc_sap *sap = llc->sap;
 216
 217		/* Hold this for release_sock(), so that llc_backlog_rcv()
 218		 * could still use it.
 219		 */
 220		llc_sap_hold(sap);
 221		llc_sap_remove_socket(llc->sap, sk);
 222		release_sock(sk);
 223		llc_sap_put(sap);
 224	} else {
 225		release_sock(sk);
 226	}
 227	netdev_put(llc->dev, &llc->dev_tracker);
 228	sock_put(sk);
 229	sock_orphan(sk);
 230	sock->sk = NULL;
 231	llc_sk_free(sk);
 232out:
 233	return 0;
 234}
 235
 236/**
 237 *	llc_ui_autoport - provide dynamically allocate SAP number
 238 *
 239 *	Provide the caller with a dynamically allocated SAP number according
 240 *	to the rules that are set in this function. Returns: 0, upon failure,
 241 *	SAP number otherwise.
 242 */
 243static int llc_ui_autoport(void)
 244{
 245	struct llc_sap *sap;
 246	int i, tries = 0;
 247
 248	while (tries < LLC_SAP_DYN_TRIES) {
 249		for (i = llc_ui_sap_last_autoport;
 250		     i < LLC_SAP_DYN_STOP; i += 2) {
 251			sap = llc_sap_find(i);
 252			if (!sap) {
 253				llc_ui_sap_last_autoport = i + 2;
 254				goto out;
 255			}
 256			llc_sap_put(sap);
 257		}
 258		llc_ui_sap_last_autoport = LLC_SAP_DYN_START;
 259		tries++;
 260	}
 261	i = 0;
 262out:
 263	return i;
 264}
 265
 266/**
 267 *	llc_ui_autobind - automatically bind a socket to a sap
 268 *	@sock: socket to bind
 269 *	@addr: address to connect to
 270 *
 271 * 	Used by llc_ui_connect and llc_ui_sendmsg when the user hasn't
 272 * 	specifically used llc_ui_bind to bind to an specific address/sap
 273 *
 274 *	Returns: 0 upon success, negative otherwise.
 275 */
 276static int llc_ui_autobind(struct socket *sock, struct sockaddr_llc *addr)
 277{
 278	struct sock *sk = sock->sk;
 279	struct llc_sock *llc = llc_sk(sk);
 280	struct net_device *dev = NULL;
 281	struct llc_sap *sap;
 282	int rc = -EINVAL;
 283
 284	if (!sock_flag(sk, SOCK_ZAPPED))
 285		goto out;
 286	if (!addr->sllc_arphrd)
 287		addr->sllc_arphrd = ARPHRD_ETHER;
 288	if (addr->sllc_arphrd != ARPHRD_ETHER)
 289		goto out;
 290	rc = -ENODEV;
 291	if (sk->sk_bound_dev_if) {
 292		dev = dev_get_by_index(&init_net, sk->sk_bound_dev_if);
 293		if (dev && addr->sllc_arphrd != dev->type) {
 294			dev_put(dev);
 295			dev = NULL;
 296		}
 297	} else
 298		dev = dev_getfirstbyhwtype(&init_net, addr->sllc_arphrd);
 299	if (!dev)
 300		goto out;
 301	rc = -EUSERS;
 302	llc->laddr.lsap = llc_ui_autoport();
 303	if (!llc->laddr.lsap)
 304		goto out;
 305	rc = -EBUSY; /* some other network layer is using the sap */
 306	sap = llc_sap_open(llc->laddr.lsap, NULL);
 307	if (!sap)
 308		goto out;
 309
 310	/* Note: We do not expect errors from this point. */
 311	llc->dev = dev;
 312	netdev_tracker_alloc(llc->dev, &llc->dev_tracker, GFP_KERNEL);
 313	dev = NULL;
 314
 315	memcpy(llc->laddr.mac, llc->dev->dev_addr, IFHWADDRLEN);
 316	memcpy(&llc->addr, addr, sizeof(llc->addr));
 317	/* assign new connection to its SAP */
 318	llc_sap_add_socket(sap, sk);
 319	sock_reset_flag(sk, SOCK_ZAPPED);
 320	rc = 0;
 321out:
 322	dev_put(dev);
 323	return rc;
 324}
 325
 326/**
 327 *	llc_ui_bind - bind a socket to a specific address.
 328 *	@sock: Socket to bind an address to.
 329 *	@uaddr: Address the user wants the socket bound to.
 330 *	@addrlen: Length of the uaddr structure.
 331 *
 332 *	Bind a socket to a specific address. For llc a user is able to bind to
 333 *	a specific sap only or mac + sap.
 334 *	If the user desires to bind to a specific mac + sap, it is possible to
 335 *	have multiple sap connections via multiple macs.
 336 *	Bind and autobind for that matter must enforce the correct sap usage
 337 *	otherwise all hell will break loose.
 338 *	Returns: 0 upon success, negative otherwise.
 339 */
 340static int llc_ui_bind(struct socket *sock, struct sockaddr *uaddr, int addrlen)
 341{
 342	struct sockaddr_llc *addr = (struct sockaddr_llc *)uaddr;
 343	struct sock *sk = sock->sk;
 344	struct llc_sock *llc = llc_sk(sk);
 345	struct net_device *dev = NULL;
 346	struct llc_sap *sap;
 347	int rc = -EINVAL;
 348
 349	lock_sock(sk);
 350	if (unlikely(!sock_flag(sk, SOCK_ZAPPED) || addrlen != sizeof(*addr)))
 351		goto out;
 352	rc = -EAFNOSUPPORT;
 353	if (!addr->sllc_arphrd)
 354		addr->sllc_arphrd = ARPHRD_ETHER;
 355	if (unlikely(addr->sllc_family != AF_LLC || addr->sllc_arphrd != ARPHRD_ETHER))
 356		goto out;
 357	dprintk("%s: binding %02X\n", __func__, addr->sllc_sap);
 358	rc = -ENODEV;
 359	rcu_read_lock();
 360	if (sk->sk_bound_dev_if) {
 361		dev = dev_get_by_index_rcu(&init_net, sk->sk_bound_dev_if);
 362		if (dev) {
 363			if (is_zero_ether_addr(addr->sllc_mac))
 364				memcpy(addr->sllc_mac, dev->dev_addr,
 365				       IFHWADDRLEN);
 366			if (addr->sllc_arphrd != dev->type ||
 367			    !ether_addr_equal(addr->sllc_mac,
 368					      dev->dev_addr)) {
 369				rc = -EINVAL;
 370				dev = NULL;
 371			}
 372		}
 373	} else {
 374		dev = dev_getbyhwaddr_rcu(&init_net, addr->sllc_arphrd,
 375					   addr->sllc_mac);
 376	}
 377	dev_hold(dev);
 378	rcu_read_unlock();
 379	if (!dev)
 380		goto out;
 381
 382	if (!addr->sllc_sap) {
 383		rc = -EUSERS;
 384		addr->sllc_sap = llc_ui_autoport();
 385		if (!addr->sllc_sap)
 386			goto out;
 387	}
 388	sap = llc_sap_find(addr->sllc_sap);
 389	if (!sap) {
 390		sap = llc_sap_open(addr->sllc_sap, NULL);
 391		rc = -EBUSY; /* some other network layer is using the sap */
 392		if (!sap)
 393			goto out;
 394	} else {
 395		struct llc_addr laddr, daddr;
 396		struct sock *ask;
 397
 398		memset(&laddr, 0, sizeof(laddr));
 399		memset(&daddr, 0, sizeof(daddr));
 400		/*
 401		 * FIXME: check if the address is multicast,
 402		 * 	  only SOCK_DGRAM can do this.
 403		 */
 404		memcpy(laddr.mac, addr->sllc_mac, IFHWADDRLEN);
 405		laddr.lsap = addr->sllc_sap;
 406		rc = -EADDRINUSE; /* mac + sap clash. */
 407		ask = llc_lookup_established(sap, &daddr, &laddr, &init_net);
 408		if (ask) {
 409			sock_put(ask);
 410			goto out_put;
 411		}
 412	}
 413
 414	/* Note: We do not expect errors from this point. */
 415	llc->dev = dev;
 416	netdev_tracker_alloc(llc->dev, &llc->dev_tracker, GFP_KERNEL);
 417	dev = NULL;
 418
 419	llc->laddr.lsap = addr->sllc_sap;
 420	memcpy(llc->laddr.mac, addr->sllc_mac, IFHWADDRLEN);
 421	memcpy(&llc->addr, addr, sizeof(llc->addr));
 422	/* assign new connection to its SAP */
 423	llc_sap_add_socket(sap, sk);
 424	sock_reset_flag(sk, SOCK_ZAPPED);
 425	rc = 0;
 426out_put:
 427	llc_sap_put(sap);
 428out:
 429	dev_put(dev);
 430	release_sock(sk);
 431	return rc;
 432}
 433
 434/**
 435 *	llc_ui_shutdown - shutdown a connect llc2 socket.
 436 *	@sock: Socket to shutdown.
 437 *	@how: What part of the socket to shutdown.
 438 *
 439 *	Shutdown a connected llc2 socket. Currently this function only supports
 440 *	shutting down both sends and receives (2), we could probably make this
 441 *	function such that a user can shutdown only half the connection but not
 442 *	right now.
 443 *	Returns: 0 upon success, negative otherwise.
 444 */
 445static int llc_ui_shutdown(struct socket *sock, int how)
 446{
 447	struct sock *sk = sock->sk;
 448	int rc = -ENOTCONN;
 449
 450	lock_sock(sk);
 451	if (unlikely(sk->sk_state != TCP_ESTABLISHED))
 452		goto out;
 453	rc = -EINVAL;
 454	if (how != 2)
 455		goto out;
 456	rc = llc_send_disc(sk);
 457	if (!rc)
 458		rc = llc_ui_wait_for_disc(sk, sk->sk_rcvtimeo);
 459	/* Wake up anyone sleeping in poll */
 460	sk->sk_state_change(sk);
 461out:
 462	release_sock(sk);
 463	return rc;
 464}
 465
 466/**
 467 *	llc_ui_connect - Connect to a remote llc2 mac + sap.
 468 *	@sock: Socket which will be connected to the remote destination.
 469 *	@uaddr: Remote and possibly the local address of the new connection.
 470 *	@addrlen: Size of uaddr structure.
 471 *	@flags: Operational flags specified by the user.
 472 *
 473 *	Connect to a remote llc2 mac + sap. The caller must specify the
 474 *	destination mac and address to connect to. If the user hasn't previously
 475 *	called bind(2) with a smac the address of the first interface of the
 476 *	specified arp type will be used.
 477 *	This function will autobind if user did not previously call bind.
 478 *	Returns: 0 upon success, negative otherwise.
 479 */
 480static int llc_ui_connect(struct socket *sock, struct sockaddr *uaddr,
 481			  int addrlen, int flags)
 482{
 483	struct sock *sk = sock->sk;
 484	struct llc_sock *llc = llc_sk(sk);
 485	struct sockaddr_llc *addr = (struct sockaddr_llc *)uaddr;
 486	int rc = -EINVAL;
 487
 488	lock_sock(sk);
 489	if (unlikely(addrlen != sizeof(*addr)))
 490		goto out;
 491	rc = -EAFNOSUPPORT;
 492	if (unlikely(addr->sllc_family != AF_LLC))
 493		goto out;
 494	if (unlikely(sk->sk_type != SOCK_STREAM))
 495		goto out;
 496	rc = -EALREADY;
 497	if (unlikely(sock->state == SS_CONNECTING))
 498		goto out;
 499	/* bind connection to sap if user hasn't done it. */
 500	if (sock_flag(sk, SOCK_ZAPPED)) {
 501		/* bind to sap with null dev, exclusive */
 502		rc = llc_ui_autobind(sock, addr);
 503		if (rc)
 504			goto out;
 505	}
 506	llc->daddr.lsap = addr->sllc_sap;
 507	memcpy(llc->daddr.mac, addr->sllc_mac, IFHWADDRLEN);
 508	sock->state = SS_CONNECTING;
 509	sk->sk_state   = TCP_SYN_SENT;
 510	llc->link   = llc_ui_next_link_no(llc->sap->laddr.lsap);
 511	rc = llc_establish_connection(sk, llc->dev->dev_addr,
 512				      addr->sllc_mac, addr->sllc_sap);
 513	if (rc) {
 514		dprintk("%s: llc_ui_send_conn failed :-(\n", __func__);
 515		sock->state  = SS_UNCONNECTED;
 516		sk->sk_state = TCP_CLOSE;
 517		goto out;
 518	}
 519
 520	if (sk->sk_state == TCP_SYN_SENT) {
 521		const long timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
 522
 523		if (!timeo || !llc_ui_wait_for_conn(sk, timeo))
 524			goto out;
 525
 526		rc = sock_intr_errno(timeo);
 527		if (signal_pending(current))
 528			goto out;
 529	}
 530
 531	if (sk->sk_state == TCP_CLOSE)
 532		goto sock_error;
 533
 534	sock->state = SS_CONNECTED;
 535	rc = 0;
 536out:
 537	release_sock(sk);
 538	return rc;
 539sock_error:
 540	rc = sock_error(sk) ? : -ECONNABORTED;
 541	sock->state = SS_UNCONNECTED;
 542	goto out;
 543}
 544
 545/**
 546 *	llc_ui_listen - allow a normal socket to accept incoming connections
 547 *	@sock: Socket to allow incoming connections on.
 548 *	@backlog: Number of connections to queue.
 549 *
 550 *	Allow a normal socket to accept incoming connections.
 551 *	Returns 0 upon success, negative otherwise.
 552 */
 553static int llc_ui_listen(struct socket *sock, int backlog)
 554{
 555	struct sock *sk = sock->sk;
 556	int rc = -EINVAL;
 557
 558	lock_sock(sk);
 559	if (unlikely(sock->state != SS_UNCONNECTED))
 560		goto out;
 561	rc = -EOPNOTSUPP;
 562	if (unlikely(sk->sk_type != SOCK_STREAM))
 563		goto out;
 564	rc = -EAGAIN;
 565	if (sock_flag(sk, SOCK_ZAPPED))
 566		goto out;
 567	rc = 0;
 568	if (!(unsigned int)backlog)	/* BSDism */
 569		backlog = 1;
 570	sk->sk_max_ack_backlog = backlog;
 571	if (sk->sk_state != TCP_LISTEN) {
 572		sk->sk_ack_backlog = 0;
 573		sk->sk_state	   = TCP_LISTEN;
 574	}
 575	sk->sk_socket->flags |= __SO_ACCEPTCON;
 576out:
 577	release_sock(sk);
 578	return rc;
 579}
 580
 581static int llc_ui_wait_for_disc(struct sock *sk, long timeout)
 582{
 583	DEFINE_WAIT_FUNC(wait, woken_wake_function);
 584	int rc = 0;
 585
 586	add_wait_queue(sk_sleep(sk), &wait);
 587	while (1) {
 588		if (sk_wait_event(sk, &timeout,
 589				  READ_ONCE(sk->sk_state) == TCP_CLOSE, &wait))
 590			break;
 591		rc = -ERESTARTSYS;
 592		if (signal_pending(current))
 593			break;
 594		rc = -EAGAIN;
 595		if (!timeout)
 596			break;
 597		rc = 0;
 598	}
 599	remove_wait_queue(sk_sleep(sk), &wait);
 600	return rc;
 601}
 602
 603static bool llc_ui_wait_for_conn(struct sock *sk, long timeout)
 604{
 605	DEFINE_WAIT_FUNC(wait, woken_wake_function);
 606
 607	add_wait_queue(sk_sleep(sk), &wait);
 608	while (1) {
 609		if (sk_wait_event(sk, &timeout,
 610				  READ_ONCE(sk->sk_state) != TCP_SYN_SENT, &wait))
 611			break;
 612		if (signal_pending(current) || !timeout)
 613			break;
 614	}
 615	remove_wait_queue(sk_sleep(sk), &wait);
 616	return timeout;
 617}
 618
 619static int llc_ui_wait_for_busy_core(struct sock *sk, long timeout)
 620{
 621	DEFINE_WAIT_FUNC(wait, woken_wake_function);
 622	struct llc_sock *llc = llc_sk(sk);
 623	int rc;
 624
 625	add_wait_queue(sk_sleep(sk), &wait);
 626	while (1) {
 627		rc = 0;
 628		if (sk_wait_event(sk, &timeout,
 629				  (READ_ONCE(sk->sk_shutdown) & RCV_SHUTDOWN) ||
 630				  (!llc_data_accept_state(llc->state) &&
 631				   !llc->remote_busy_flag &&
 632				   !llc->p_flag), &wait))
 633			break;
 634		rc = -ERESTARTSYS;
 635		if (signal_pending(current))
 636			break;
 637		rc = -EAGAIN;
 638		if (!timeout)
 639			break;
 640	}
 641	remove_wait_queue(sk_sleep(sk), &wait);
 642	return rc;
 643}
 644
 645static int llc_wait_data(struct sock *sk, long timeo)
 646{
 647	int rc;
 648
 649	while (1) {
 650		/*
 651		 * POSIX 1003.1g mandates this order.
 652		 */
 653		rc = sock_error(sk);
 654		if (rc)
 655			break;
 656		rc = 0;
 657		if (sk->sk_shutdown & RCV_SHUTDOWN)
 658			break;
 659		rc = -EAGAIN;
 660		if (!timeo)
 661			break;
 662		rc = sock_intr_errno(timeo);
 663		if (signal_pending(current))
 664			break;
 665		rc = 0;
 666		if (sk_wait_data(sk, &timeo, NULL))
 667			break;
 668	}
 669	return rc;
 670}
 671
 672static void llc_cmsg_rcv(struct msghdr *msg, struct sk_buff *skb)
 673{
 674	struct llc_sock *llc = llc_sk(skb->sk);
 675
 676	if (llc->cmsg_flags & LLC_CMSG_PKTINFO) {
 677		struct llc_pktinfo info;
 678
 679		memset(&info, 0, sizeof(info));
 680		info.lpi_ifindex = llc_sk(skb->sk)->dev->ifindex;
 681		llc_pdu_decode_dsap(skb, &info.lpi_sap);
 682		llc_pdu_decode_da(skb, info.lpi_mac);
 683		put_cmsg(msg, SOL_LLC, LLC_OPT_PKTINFO, sizeof(info), &info);
 684	}
 685}
 686
 687/**
 688 *	llc_ui_accept - accept a new incoming connection.
 689 *	@sock: Socket which connections arrive on.
 690 *	@newsock: Socket to move incoming connection to.
 691 *	@arg: User specified arguments
 
 692 *
 693 *	Accept a new incoming connection.
 694 *	Returns 0 upon success, negative otherwise.
 695 */
 696static int llc_ui_accept(struct socket *sock, struct socket *newsock,
 697			 struct proto_accept_arg *arg)
 698{
 699	struct sock *sk = sock->sk, *newsk;
 700	struct llc_sock *llc, *newllc;
 701	struct sk_buff *skb;
 702	int rc = -EOPNOTSUPP;
 703
 704	dprintk("%s: accepting on %02X\n", __func__,
 705		llc_sk(sk)->laddr.lsap);
 706	lock_sock(sk);
 707	if (unlikely(sk->sk_type != SOCK_STREAM))
 708		goto out;
 709	rc = -EINVAL;
 710	if (unlikely(sock->state != SS_UNCONNECTED ||
 711		     sk->sk_state != TCP_LISTEN))
 712		goto out;
 713	/* wait for a connection to arrive. */
 714	if (skb_queue_empty(&sk->sk_receive_queue)) {
 715		rc = llc_wait_data(sk, sk->sk_rcvtimeo);
 716		if (rc)
 717			goto out;
 718	}
 719	dprintk("%s: got a new connection on %02X\n", __func__,
 720		llc_sk(sk)->laddr.lsap);
 721	skb = skb_dequeue(&sk->sk_receive_queue);
 722	rc = -EINVAL;
 723	if (!skb->sk)
 724		goto frees;
 725	rc = 0;
 726	newsk = skb->sk;
 727	/* attach connection to a new socket. */
 728	llc_ui_sk_init(newsock, newsk);
 729	sock_reset_flag(newsk, SOCK_ZAPPED);
 730	newsk->sk_state		= TCP_ESTABLISHED;
 731	newsock->state		= SS_CONNECTED;
 732	llc			= llc_sk(sk);
 733	newllc			= llc_sk(newsk);
 734	memcpy(&newllc->addr, &llc->addr, sizeof(newllc->addr));
 735	newllc->link = llc_ui_next_link_no(newllc->laddr.lsap);
 736
 737	/* put original socket back into a clean listen state. */
 738	sk->sk_state = TCP_LISTEN;
 739	sk_acceptq_removed(sk);
 740	dprintk("%s: ok success on %02X, client on %02X\n", __func__,
 741		llc_sk(sk)->addr.sllc_sap, newllc->daddr.lsap);
 742frees:
 743	kfree_skb(skb);
 744out:
 745	release_sock(sk);
 746	return rc;
 747}
 748
 749/**
 750 *	llc_ui_recvmsg - copy received data to the socket user.
 751 *	@sock: Socket to copy data from.
 752 *	@msg: Various user space related information.
 753 *	@len: Size of user buffer.
 754 *	@flags: User specified flags.
 755 *
 756 *	Copy received data to the socket user.
 757 *	Returns non-negative upon success, negative otherwise.
 758 */
 759static int llc_ui_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
 760			  int flags)
 761{
 762	DECLARE_SOCKADDR(struct sockaddr_llc *, uaddr, msg->msg_name);
 763	const int nonblock = flags & MSG_DONTWAIT;
 764	struct sk_buff *skb = NULL;
 765	struct sock *sk = sock->sk;
 766	struct llc_sock *llc = llc_sk(sk);
 767	size_t copied = 0;
 768	u32 peek_seq = 0;
 769	u32 *seq, skb_len;
 770	unsigned long used;
 771	int target;	/* Read at least this many bytes */
 772	long timeo;
 773
 774	lock_sock(sk);
 775	copied = -ENOTCONN;
 776	if (unlikely(sk->sk_type == SOCK_STREAM && sk->sk_state == TCP_LISTEN))
 777		goto out;
 778
 779	timeo = sock_rcvtimeo(sk, nonblock);
 780
 781	seq = &llc->copied_seq;
 782	if (flags & MSG_PEEK) {
 783		peek_seq = llc->copied_seq;
 784		seq = &peek_seq;
 785	}
 786
 787	target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
 788	copied = 0;
 789
 790	do {
 791		u32 offset;
 792
 793		/*
 794		 * We need to check signals first, to get correct SIGURG
 795		 * handling. FIXME: Need to check this doesn't impact 1003.1g
 796		 * and move it down to the bottom of the loop
 797		 */
 798		if (signal_pending(current)) {
 799			if (copied)
 800				break;
 801			copied = timeo ? sock_intr_errno(timeo) : -EAGAIN;
 802			break;
 803		}
 804
 805		/* Next get a buffer. */
 806
 807		skb = skb_peek(&sk->sk_receive_queue);
 808		if (skb) {
 809			offset = *seq;
 810			goto found_ok_skb;
 811		}
 812		/* Well, if we have backlog, try to process it now yet. */
 813
 814		if (copied >= target && !READ_ONCE(sk->sk_backlog.tail))
 815			break;
 816
 817		if (copied) {
 818			if (sk->sk_err ||
 819			    sk->sk_state == TCP_CLOSE ||
 820			    (sk->sk_shutdown & RCV_SHUTDOWN) ||
 821			    !timeo ||
 822			    (flags & MSG_PEEK))
 823				break;
 824		} else {
 825			if (sock_flag(sk, SOCK_DONE))
 826				break;
 827
 828			if (sk->sk_err) {
 829				copied = sock_error(sk);
 830				break;
 831			}
 832			if (sk->sk_shutdown & RCV_SHUTDOWN)
 833				break;
 834
 835			if (sk->sk_type == SOCK_STREAM && sk->sk_state == TCP_CLOSE) {
 836				if (!sock_flag(sk, SOCK_DONE)) {
 837					/*
 838					 * This occurs when user tries to read
 839					 * from never connected socket.
 840					 */
 841					copied = -ENOTCONN;
 842					break;
 843				}
 844				break;
 845			}
 846			if (!timeo) {
 847				copied = -EAGAIN;
 848				break;
 849			}
 850		}
 851
 852		if (copied >= target) { /* Do not sleep, just process backlog. */
 853			release_sock(sk);
 854			lock_sock(sk);
 855		} else
 856			sk_wait_data(sk, &timeo, NULL);
 857
 858		if ((flags & MSG_PEEK) && peek_seq != llc->copied_seq) {
 859			net_dbg_ratelimited("LLC(%s:%d): Application bug, race in MSG_PEEK\n",
 860					    current->comm,
 861					    task_pid_nr(current));
 862			peek_seq = llc->copied_seq;
 863		}
 864		continue;
 865	found_ok_skb:
 866		skb_len = skb->len;
 867		/* Ok so how much can we use? */
 868		used = skb->len - offset;
 869		if (len < used)
 870			used = len;
 871
 872		if (!(flags & MSG_TRUNC)) {
 873			int rc = skb_copy_datagram_msg(skb, offset, msg, used);
 874			if (rc) {
 875				/* Exception. Bailout! */
 876				if (!copied)
 877					copied = -EFAULT;
 878				break;
 879			}
 880		}
 881
 882		*seq += used;
 883		copied += used;
 884		len -= used;
 885
 886		/* For non stream protcols we get one packet per recvmsg call */
 887		if (sk->sk_type != SOCK_STREAM)
 888			goto copy_uaddr;
 889
 890		if (!(flags & MSG_PEEK)) {
 891			skb_unlink(skb, &sk->sk_receive_queue);
 892			kfree_skb(skb);
 893			*seq = 0;
 894		}
 895
 896		/* Partial read */
 897		if (used + offset < skb_len)
 898			continue;
 899	} while (len > 0);
 900
 901out:
 902	release_sock(sk);
 903	return copied;
 904copy_uaddr:
 905	if (uaddr != NULL && skb != NULL) {
 906		memcpy(uaddr, llc_ui_skb_cb(skb), sizeof(*uaddr));
 907		msg->msg_namelen = sizeof(*uaddr);
 908	}
 909	if (llc_sk(sk)->cmsg_flags)
 910		llc_cmsg_rcv(msg, skb);
 911
 912	if (!(flags & MSG_PEEK)) {
 913		skb_unlink(skb, &sk->sk_receive_queue);
 914		kfree_skb(skb);
 915		*seq = 0;
 916	}
 917
 918	goto out;
 919}
 920
 921/**
 922 *	llc_ui_sendmsg - Transmit data provided by the socket user.
 923 *	@sock: Socket to transmit data from.
 924 *	@msg: Various user related information.
 925 *	@len: Length of data to transmit.
 926 *
 927 *	Transmit data provided by the socket user.
 928 *	Returns non-negative upon success, negative otherwise.
 929 */
 930static int llc_ui_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
 931{
 932	DECLARE_SOCKADDR(struct sockaddr_llc *, addr, msg->msg_name);
 933	struct sock *sk = sock->sk;
 934	struct llc_sock *llc = llc_sk(sk);
 
 935	int flags = msg->msg_flags;
 936	int noblock = flags & MSG_DONTWAIT;
 937	int rc = -EINVAL, copied = 0, hdrlen, hh_len;
 938	struct sk_buff *skb = NULL;
 939	struct net_device *dev;
 940	size_t size = 0;
 
 941
 942	dprintk("%s: sending from %02X to %02X\n", __func__,
 943		llc->laddr.lsap, llc->daddr.lsap);
 944	lock_sock(sk);
 945	if (addr) {
 946		if (msg->msg_namelen < sizeof(*addr))
 947			goto out;
 948	} else {
 949		if (llc_ui_addr_null(&llc->addr))
 950			goto out;
 951		addr = &llc->addr;
 952	}
 953	/* must bind connection to sap if user hasn't done it. */
 954	if (sock_flag(sk, SOCK_ZAPPED)) {
 955		/* bind to sap with null dev, exclusive. */
 956		rc = llc_ui_autobind(sock, addr);
 957		if (rc)
 958			goto out;
 959	}
 960	dev = llc->dev;
 961	hh_len = LL_RESERVED_SPACE(dev);
 962	hdrlen = llc_ui_header_len(sk, addr);
 963	size = hdrlen + len;
 964	size = min_t(size_t, size, READ_ONCE(dev->mtu));
 
 965	copied = size - hdrlen;
 966	rc = -EINVAL;
 967	if (copied < 0)
 968		goto out;
 969	release_sock(sk);
 970	skb = sock_alloc_send_skb(sk, hh_len + size, noblock, &rc);
 971	lock_sock(sk);
 972	if (!skb)
 973		goto out;
 974	if (sock_flag(sk, SOCK_ZAPPED) ||
 975	    llc->dev != dev ||
 976	    hdrlen != llc_ui_header_len(sk, addr) ||
 977	    hh_len != LL_RESERVED_SPACE(dev) ||
 978	    size > READ_ONCE(dev->mtu))
 979		goto out;
 980	skb->dev      = dev;
 981	skb->protocol = llc_proto_type(addr->sllc_arphrd);
 982	skb_reserve(skb, hh_len + hdrlen);
 983	rc = memcpy_from_msg(skb_put(skb, copied), msg, copied);
 984	if (rc)
 985		goto out;
 986	if (sk->sk_type == SOCK_DGRAM || addr->sllc_ua) {
 987		llc_build_and_send_ui_pkt(llc->sap, skb, addr->sllc_mac,
 988					  addr->sllc_sap);
 989		skb = NULL;
 990		goto out;
 991	}
 992	if (addr->sllc_test) {
 993		llc_build_and_send_test_pkt(llc->sap, skb, addr->sllc_mac,
 994					    addr->sllc_sap);
 995		skb = NULL;
 996		goto out;
 997	}
 998	if (addr->sllc_xid) {
 999		llc_build_and_send_xid_pkt(llc->sap, skb, addr->sllc_mac,
1000					   addr->sllc_sap);
1001		skb = NULL;
1002		goto out;
1003	}
1004	rc = -ENOPROTOOPT;
1005	if (!(sk->sk_type == SOCK_STREAM && !addr->sllc_ua))
1006		goto out;
1007	rc = llc_ui_send_data(sk, skb, noblock);
1008	skb = NULL;
1009out:
1010	kfree_skb(skb);
1011	if (rc)
1012		dprintk("%s: failed sending from %02X to %02X: %d\n",
1013			__func__, llc->laddr.lsap, llc->daddr.lsap, rc);
1014	release_sock(sk);
1015	return rc ? : copied;
1016}
1017
1018/**
1019 *	llc_ui_getname - return the address info of a socket
1020 *	@sock: Socket to get address of.
1021 *	@uaddr: Address structure to return information.
1022 *	@peer: Does user want local or remote address information.
1023 *
1024 *	Return the address information of a socket.
1025 */
1026static int llc_ui_getname(struct socket *sock, struct sockaddr *uaddr,
1027			  int peer)
1028{
1029	struct sockaddr_llc sllc;
1030	struct sock *sk = sock->sk;
1031	struct llc_sock *llc = llc_sk(sk);
1032	int rc = -EBADF;
1033
1034	memset(&sllc, 0, sizeof(sllc));
1035	lock_sock(sk);
1036	if (sock_flag(sk, SOCK_ZAPPED))
1037		goto out;
1038	if (peer) {
1039		rc = -ENOTCONN;
1040		if (sk->sk_state != TCP_ESTABLISHED)
1041			goto out;
1042		if(llc->dev)
1043			sllc.sllc_arphrd = llc->dev->type;
1044		sllc.sllc_sap = llc->daddr.lsap;
1045		memcpy(&sllc.sllc_mac, &llc->daddr.mac, IFHWADDRLEN);
1046	} else {
1047		rc = -EINVAL;
1048		if (!llc->sap)
1049			goto out;
1050		sllc.sllc_sap = llc->sap->laddr.lsap;
1051
1052		if (llc->dev) {
1053			sllc.sllc_arphrd = llc->dev->type;
1054			memcpy(&sllc.sllc_mac, llc->dev->dev_addr,
1055			       IFHWADDRLEN);
1056		}
1057	}
1058	sllc.sllc_family = AF_LLC;
1059	memcpy(uaddr, &sllc, sizeof(sllc));
1060	rc = sizeof(sllc);
1061out:
1062	release_sock(sk);
1063	return rc;
1064}
1065
1066/**
1067 *	llc_ui_ioctl - io controls for PF_LLC
1068 *	@sock: Socket to get/set info
1069 *	@cmd: command
1070 *	@arg: optional argument for cmd
1071 *
1072 *	get/set info on llc sockets
1073 */
1074static int llc_ui_ioctl(struct socket *sock, unsigned int cmd,
1075			unsigned long arg)
1076{
1077	return -ENOIOCTLCMD;
1078}
1079
1080/**
1081 *	llc_ui_setsockopt - set various connection specific parameters.
1082 *	@sock: Socket to set options on.
1083 *	@level: Socket level user is requesting operations on.
1084 *	@optname: Operation name.
1085 *	@optval: User provided operation data.
1086 *	@optlen: Length of optval.
1087 *
1088 *	Set various connection specific parameters.
1089 */
1090static int llc_ui_setsockopt(struct socket *sock, int level, int optname,
1091			     sockptr_t optval, unsigned int optlen)
1092{
1093	struct sock *sk = sock->sk;
1094	struct llc_sock *llc = llc_sk(sk);
1095	unsigned int opt;
1096	int rc = -EINVAL;
1097
1098	lock_sock(sk);
1099	if (unlikely(level != SOL_LLC || optlen != sizeof(int)))
1100		goto out;
1101	rc = copy_safe_from_sockptr(&opt, sizeof(opt), optval, optlen);
1102	if (rc)
1103		goto out;
1104	rc = -EINVAL;
1105	switch (optname) {
1106	case LLC_OPT_RETRY:
1107		if (opt > LLC_OPT_MAX_RETRY)
1108			goto out;
1109		llc->n2 = opt;
1110		break;
1111	case LLC_OPT_SIZE:
1112		if (opt > LLC_OPT_MAX_SIZE)
1113			goto out;
1114		llc->n1 = opt;
1115		break;
1116	case LLC_OPT_ACK_TMR_EXP:
1117		if (opt > LLC_OPT_MAX_ACK_TMR_EXP)
1118			goto out;
1119		llc->ack_timer.expire = opt * HZ;
1120		break;
1121	case LLC_OPT_P_TMR_EXP:
1122		if (opt > LLC_OPT_MAX_P_TMR_EXP)
1123			goto out;
1124		llc->pf_cycle_timer.expire = opt * HZ;
1125		break;
1126	case LLC_OPT_REJ_TMR_EXP:
1127		if (opt > LLC_OPT_MAX_REJ_TMR_EXP)
1128			goto out;
1129		llc->rej_sent_timer.expire = opt * HZ;
1130		break;
1131	case LLC_OPT_BUSY_TMR_EXP:
1132		if (opt > LLC_OPT_MAX_BUSY_TMR_EXP)
1133			goto out;
1134		llc->busy_state_timer.expire = opt * HZ;
1135		break;
1136	case LLC_OPT_TX_WIN:
1137		if (opt > LLC_OPT_MAX_WIN)
1138			goto out;
1139		llc->k = opt;
1140		break;
1141	case LLC_OPT_RX_WIN:
1142		if (opt > LLC_OPT_MAX_WIN)
1143			goto out;
1144		llc->rw = opt;
1145		break;
1146	case LLC_OPT_PKTINFO:
1147		if (opt)
1148			llc->cmsg_flags |= LLC_CMSG_PKTINFO;
1149		else
1150			llc->cmsg_flags &= ~LLC_CMSG_PKTINFO;
1151		break;
1152	default:
1153		rc = -ENOPROTOOPT;
1154		goto out;
1155	}
1156	rc = 0;
1157out:
1158	release_sock(sk);
1159	return rc;
1160}
1161
1162/**
1163 *	llc_ui_getsockopt - get connection specific socket info
1164 *	@sock: Socket to get information from.
1165 *	@level: Socket level user is requesting operations on.
1166 *	@optname: Operation name.
1167 *	@optval: Variable to return operation data in.
1168 *	@optlen: Length of optval.
1169 *
1170 *	Get connection specific socket information.
1171 */
1172static int llc_ui_getsockopt(struct socket *sock, int level, int optname,
1173			     char __user *optval, int __user *optlen)
1174{
1175	struct sock *sk = sock->sk;
1176	struct llc_sock *llc = llc_sk(sk);
1177	int val = 0, len = 0, rc = -EINVAL;
1178
1179	lock_sock(sk);
1180	if (unlikely(level != SOL_LLC))
1181		goto out;
1182	rc = get_user(len, optlen);
1183	if (rc)
1184		goto out;
1185	rc = -EINVAL;
1186	if (len != sizeof(int))
1187		goto out;
1188	switch (optname) {
1189	case LLC_OPT_RETRY:
1190		val = llc->n2;					break;
1191	case LLC_OPT_SIZE:
1192		val = llc->n1;					break;
1193	case LLC_OPT_ACK_TMR_EXP:
1194		val = llc->ack_timer.expire / HZ;		break;
1195	case LLC_OPT_P_TMR_EXP:
1196		val = llc->pf_cycle_timer.expire / HZ;		break;
1197	case LLC_OPT_REJ_TMR_EXP:
1198		val = llc->rej_sent_timer.expire / HZ;		break;
1199	case LLC_OPT_BUSY_TMR_EXP:
1200		val = llc->busy_state_timer.expire / HZ;	break;
1201	case LLC_OPT_TX_WIN:
1202		val = llc->k;				break;
1203	case LLC_OPT_RX_WIN:
1204		val = llc->rw;				break;
1205	case LLC_OPT_PKTINFO:
1206		val = (llc->cmsg_flags & LLC_CMSG_PKTINFO) != 0;
1207		break;
1208	default:
1209		rc = -ENOPROTOOPT;
1210		goto out;
1211	}
1212	rc = 0;
1213	if (put_user(len, optlen) || copy_to_user(optval, &val, len))
1214		rc = -EFAULT;
1215out:
1216	release_sock(sk);
1217	return rc;
1218}
1219
1220static const struct net_proto_family llc_ui_family_ops = {
1221	.family = PF_LLC,
1222	.create = llc_ui_create,
1223	.owner	= THIS_MODULE,
1224};
1225
1226static const struct proto_ops llc_ui_ops = {
1227	.family	     = PF_LLC,
1228	.owner       = THIS_MODULE,
1229	.release     = llc_ui_release,
1230	.bind	     = llc_ui_bind,
1231	.connect     = llc_ui_connect,
1232	.socketpair  = sock_no_socketpair,
1233	.accept      = llc_ui_accept,
1234	.getname     = llc_ui_getname,
1235	.poll	     = datagram_poll,
1236	.ioctl       = llc_ui_ioctl,
1237	.listen      = llc_ui_listen,
1238	.shutdown    = llc_ui_shutdown,
1239	.setsockopt  = llc_ui_setsockopt,
1240	.getsockopt  = llc_ui_getsockopt,
1241	.sendmsg     = llc_ui_sendmsg,
1242	.recvmsg     = llc_ui_recvmsg,
1243	.mmap	     = sock_no_mmap,
 
1244};
1245
1246static const char llc_proc_err_msg[] __initconst =
1247	KERN_CRIT "LLC: Unable to register the proc_fs entries\n";
1248static const char llc_sysctl_err_msg[] __initconst =
1249	KERN_CRIT "LLC: Unable to register the sysctl entries\n";
1250static const char llc_sock_err_msg[] __initconst =
1251	KERN_CRIT "LLC: Unable to register the network family\n";
1252
1253static int __init llc2_init(void)
1254{
1255	int rc = proto_register(&llc_proto, 0);
1256
1257	if (rc != 0)
1258		goto out;
1259
1260	llc_build_offset_table();
1261	llc_station_init();
1262	llc_ui_sap_last_autoport = LLC_SAP_DYN_START;
1263	rc = llc_proc_init();
1264	if (rc != 0) {
1265		printk(llc_proc_err_msg);
1266		goto out_station;
1267	}
1268	rc = llc_sysctl_init();
1269	if (rc) {
1270		printk(llc_sysctl_err_msg);
1271		goto out_proc;
1272	}
1273	rc = sock_register(&llc_ui_family_ops);
1274	if (rc) {
1275		printk(llc_sock_err_msg);
1276		goto out_sysctl;
1277	}
1278	llc_add_pack(LLC_DEST_SAP, llc_sap_handler);
1279	llc_add_pack(LLC_DEST_CONN, llc_conn_handler);
1280out:
1281	return rc;
1282out_sysctl:
1283	llc_sysctl_exit();
1284out_proc:
1285	llc_proc_exit();
1286out_station:
1287	llc_station_exit();
1288	proto_unregister(&llc_proto);
1289	goto out;
1290}
1291
1292static void __exit llc2_exit(void)
1293{
1294	llc_station_exit();
1295	llc_remove_pack(LLC_DEST_SAP);
1296	llc_remove_pack(LLC_DEST_CONN);
1297	sock_unregister(PF_LLC);
1298	llc_proc_exit();
1299	llc_sysctl_exit();
1300	proto_unregister(&llc_proto);
1301}
1302
1303module_init(llc2_init);
1304module_exit(llc2_exit);
1305
1306MODULE_LICENSE("GPL");
1307MODULE_AUTHOR("Procom 1997, Jay Schullist 2001, Arnaldo C. Melo 2001-2003");
1308MODULE_DESCRIPTION("IEEE 802.2 PF_LLC support");
1309MODULE_ALIAS_NETPROTO(PF_LLC);