net/llc/af_llc.c

   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/config.h>
  24 #include <linux/kernel.h>
  25 #include <linux/module.h>
  26 #include <linux/rtnetlink.h>
  27 #include <linux/init.h>
  28 #include <net/llc.h>
  29 #include <net/llc_sap.h>
  30 #include <net/llc_pdu.h>
  31 #include <net/llc_conn.h>
  32 #include <net/tcp_states.h>
  33
  34 /* remember: uninitialized global data is zeroed because its in .bss */
  35 static u16 llc_ui_sap_last_autoport = LLC_SAP_DYN_START;
  36 static u16 llc_ui_sap_link_no_max[256];
  37 static struct sockaddr_llc llc_ui_addrnull;
  38 static struct proto_ops llc_ui_ops;
  39
  40 static int llc_ui_wait_for_conn(struct sock *sk, long timeout);
  41 static int llc_ui_wait_for_disc(struct sock *sk, long timeout);
  42 static int llc_ui_wait_for_data(struct sock *sk, long timeout);
  43 static int llc_ui_wait_for_busy_core(struct sock *sk, long timeout);
  44
  45 #if 0
  46 #define dprintk(args...) printk(KERN_DEBUG args)
  47 #else
  48 #define dprintk(args...)
  49 #endif
  50
  51 /**
  52  *      llc_ui_next_link_no - return the next unused link number for a sap
  53  *      @sap: Address of sap to get link number from.
  54  *
  55  *      Return the next unused link number for a given sap.
  56  */
  57 static __inline__ u16 llc_ui_next_link_no(int sap)
  58 {
  59         return llc_ui_sap_link_no_max[sap]++;
  60 }
  61
  62 /**
  63  *      llc_proto_type - return eth protocol for ARP header type
  64  *      @arphrd: ARP header type.
  65  *
  66  *      Given an ARP header type return the corresponding ethernet protocol.
  67  */
  68 static __inline__ u16 llc_proto_type(u16 arphrd)
  69 {
  70         return arphrd == ARPHRD_IEEE802_TR ?
  71                          htons(ETH_P_TR_802_2) : htons(ETH_P_802_2);
  72 }
  73
  74 /**
  75  *      llc_ui_addr_null - determines if a address structure is null
  76  *      @addr: Address to test if null.
  77  */
  78 static __inline__ u8 llc_ui_addr_null(struct sockaddr_llc *addr)
  79 {
  80         return !memcmp(addr, &llc_ui_addrnull, sizeof(*addr));
  81 }
  82
  83 /**
  84  *      llc_ui_header_len - return length of llc header based on operation
  85  *      @sk: Socket which contains a valid llc socket type.
  86  *      @addr: Complete sockaddr_llc structure received from the user.
  87  *
  88  *      Provide the length of the llc header depending on what kind of
  89  *      operation the user would like to perform and the type of socket.
  90  *      Returns the correct llc header length.
  91  */
  92 static __inline__ u8 llc_ui_header_len(struct sock *sk,
  93                                        struct sockaddr_llc *addr)
  94 {
  95         u8 rc = LLC_PDU_LEN_U;
  96
  97         if (addr->sllc_test || addr->sllc_xid)
  98                 rc = LLC_PDU_LEN_U;
  99         else if (sk->sk_type == SOCK_STREAM)
 100                 rc = LLC_PDU_LEN_I;
 101         return rc;
 102 }
 103
 104 /**
 105  *      llc_ui_send_data - send data via reliable llc2 connection
 106  *      @sk: Connection the socket is using.
 107  *      @skb: Data the user wishes to send.
 108  *      @addr: Source and destination fields provided by the user.
 109  *      @noblock: can we block waiting for data?
 110  *
 111  *      Send data via reliable llc2 connection.
 112  *      Returns 0 upon success, non-zero if action did not succeed.
 113  */
 114 static int llc_ui_send_data(struct sock* sk, struct sk_buff *skb, int noblock)
 115 {
 116         struct llc_sock* llc = llc_sk(sk);
 117         int rc = 0;
 118
 119         if (llc_data_accept_state(llc->state) || llc->p_flag) {
 120                 long timeout = sock_sndtimeo(sk, noblock);
 121
 122                 rc = llc_ui_wait_for_busy_core(sk, timeout);
 123         }
 124         if (!rc)
 125                 rc = llc_build_and_send_pkt(sk, skb);
 126         return rc;
 127 }
 128
 129 static void llc_ui_sk_init(struct socket *sock, struct sock *sk)
 130 {
 131         sk->sk_type     = sock->type;
 132         sk->sk_sleep    = &sock->wait;
 133         sk->sk_socket   = sock;
 134         sock->sk        = sk;
 135         sock->ops       = &llc_ui_ops;
 136 }
 137
 138 static struct proto llc_proto = {
 139         .name     = "DDP",
 140         .owner    = THIS_MODULE,
 141         .obj_size = sizeof(struct llc_sock),
 142 };
 143
 144 /**
 145  *      llc_ui_create - alloc and init a new llc_ui socket
 146  *      @sock: Socket to initialize and attach allocated sk to.
 147  *      @protocol: Unused.
 148  *
 149  *      Allocate and initialize a new llc_ui socket, validate the user wants a
 150  *      socket type we have available.
 151  *      Returns 0 upon success, negative upon failure.
 152  */
 153 static int llc_ui_create(struct socket *sock, int protocol)
 154 {
 155         struct sock *sk;
 156         int rc = -ESOCKTNOSUPPORT;
 157
 158         if (likely(sock->type == SOCK_DGRAM || sock->type == SOCK_STREAM)) {
 159                 rc = -ENOMEM;
 160                 sk = llc_sk_alloc(PF_LLC, GFP_KERNEL, &llc_proto);
 161                 if (sk) {
 162                         rc = 0;
 163                         llc_ui_sk_init(sock, sk);
 164                 }
 165         }
 166         return rc;
 167 }
 168
 169 /**
 170  *      llc_ui_release - shutdown socket
 171  *      @sock: Socket to release.
 172  *
 173  *      Shutdown and deallocate an existing socket.
 174  */
 175 static int llc_ui_release(struct socket *sock)
 176 {
 177         struct sock *sk = sock->sk;
 178         struct llc_sock *llc;
 179
 180         if (unlikely(sk == NULL))
 181                 goto out;
 182         sock_hold(sk);
 183         lock_sock(sk);
 184         llc = llc_sk(sk);
 185         dprintk("%s: closing local(%02X) remote(%02X)\n", __FUNCTION__,
 186                 llc->laddr.lsap, llc->daddr.lsap);
 187         if (!llc_send_disc(sk))
 188                 llc_ui_wait_for_disc(sk, sk->sk_rcvtimeo);
 189         if (!sock_flag(sk, SOCK_ZAPPED))
 190                 llc_sap_remove_socket(llc->sap, sk);
 191         release_sock(sk);
 192         if (llc->sap && hlist_empty(&llc->sap->sk_list.list)) {
 193                 llc_release_sockets(llc->sap);
 194                 llc_sap_close(llc->sap);
 195         }
 196         if (llc->dev)
 197                 dev_put(llc->dev);
 198         sock_put(sk);
 199         llc_sk_free(sk);
 200 out:
 201         return 0;
 202 }
 203
 204 /**
 205  *      llc_ui_autoport - provide dynamically allocate SAP number
 206  *
 207  *      Provide the caller with a dynamically allocated SAP number according
 208  *      to the rules that are set in this function. Returns: 0, upon failure,
 209  *      SAP number otherwise.
 210  */
 211 static int llc_ui_autoport(void)
 212 {
 213         struct llc_sap *sap;
 214         int i, tries = 0;
 215
 216         while (tries < LLC_SAP_DYN_TRIES) {
 217                 for (i = llc_ui_sap_last_autoport;
 218                      i < LLC_SAP_DYN_STOP; i += 2) {
 219                         sap = llc_sap_find(i);
 220                         if (!sap) {
 221                                 llc_ui_sap_last_autoport = i + 2;
 222                                 goto out;
 223                         }
 224                 }
 225                 llc_ui_sap_last_autoport = LLC_SAP_DYN_START;
 226                 tries++;
 227         }
 228         i = 0;
 229 out:
 230         return i;
 231 }
 232
 233 /**
 234  *      llc_ui_autobind - automatically bind a socket to a sap
 235  *      @sock: socket to bind
 236  *      @addr: address to connect to
 237  *
 238  *      Used by llc_ui_connect and llc_ui_sendmsg when the user hasn't
 239  *      specifically used llc_ui_bind to bind to an specific address/sap
 240  *
 241  *      Returns: 0 upon success, negative otherwise.
 242  */
 243 static int llc_ui_autobind(struct socket *sock, struct sockaddr_llc *addr)
 244 {
 245         struct sock *sk = sock->sk;
 246         struct llc_sock *llc = llc_sk(sk);
 247         struct llc_sap *sap;
 248         int rc = -EINVAL;
 249
 250         if (!sock_flag(sk, SOCK_ZAPPED))
 251                 goto out;
 252         rc = -ENODEV;
 253         llc->dev = dev_getfirstbyhwtype(addr->sllc_arphrd);
 254         if (!llc->dev)
 255                 goto out;
 256         rc = -EUSERS;
 257         llc->laddr.lsap = llc_ui_autoport();
 258         if (!llc->laddr.lsap)
 259                 goto out;
 260         rc = -EBUSY; /* some other network layer is using the sap */
 261         sap = llc_sap_open(llc->laddr.lsap, NULL);
 262         if (!sap)
 263                 goto out;
 264         memcpy(llc->laddr.mac, llc->dev->dev_addr, IFHWADDRLEN);
 265         memcpy(&llc->addr, addr, sizeof(llc->addr));
 266         /* assign new connection to its SAP */
 267         llc_sap_add_socket(sap, sk);
 268         sock_reset_flag(sk, SOCK_ZAPPED);
 269         rc = 0;
 270 out:
 271         return rc;
 272 }
 273
 274 /**
 275  *      llc_ui_bind - bind a socket to a specific address.
 276  *      @sock: Socket to bind an address to.
 277  *      @uaddr: Address the user wants the socket bound to.
 278  *      @addrlen: Length of the uaddr structure.
 279  *
 280  *      Bind a socket to a specific address. For llc a user is able to bind to
 281  *      a specific sap only or mac + sap.
 282  *      If the user desires to bind to a specific mac + sap, it is possible to
 283  *      have multiple sap connections via multiple macs.
 284  *      Bind and autobind for that matter must enforce the correct sap usage
 285  *      otherwise all hell will break loose.
 286  *      Returns: 0 upon success, negative otherwise.
 287  */
 288 static int llc_ui_bind(struct socket *sock, struct sockaddr *uaddr, int addrlen)
 289 {
 290         struct sockaddr_llc *addr = (struct sockaddr_llc *)uaddr;
 291         struct sock *sk = sock->sk;
 292         struct llc_sock *llc = llc_sk(sk);
 293         struct llc_sap *sap;
 294         int rc = -EINVAL;
 295
 296         dprintk("%s: binding %02X\n", __FUNCTION__, addr->sllc_sap);
 297         if (unlikely(!sock_flag(sk, SOCK_ZAPPED) || addrlen != sizeof(*addr)))
 298                 goto out;
 299         rc = -EAFNOSUPPORT;
 300         if (unlikely(addr->sllc_family != AF_LLC))
 301                 goto out;
 302         if (!addr->sllc_sap) {
 303                 rc = -EUSERS;
 304                 addr->sllc_sap = llc_ui_autoport();
 305                 if (!addr->sllc_sap)
 306                         goto out;
 307         }
 308         sap = llc_sap_find(addr->sllc_sap);
 309         if (!sap) {
 310                 sap = llc_sap_open(addr->sllc_sap, NULL);
 311                 rc = -EBUSY; /* some other network layer is using the sap */
 312                 if (!sap)
 313                         goto out;
 314         } else {
 315                 struct llc_addr laddr, daddr;
 316                 struct sock *ask;
 317
 318                 memset(&laddr, 0, sizeof(laddr));
 319                 memset(&daddr, 0, sizeof(daddr));
 320                 /*
 321                  * FIXME: check if the the address is multicast,
 322                  *        only SOCK_DGRAM can do this.
 323                  */
 324                 memcpy(laddr.mac, addr->sllc_mac, IFHWADDRLEN);
 325                 laddr.lsap = addr->sllc_sap;
 326                 rc = -EADDRINUSE; /* mac + sap clash. */
 327                 ask = llc_lookup_established(sap, &daddr, &laddr);
 328                 if (ask) {
 329                         sock_put(ask);
 330                         goto out;
 331                 }
 332         }
 333         llc->laddr.lsap = addr->sllc_sap;
 334         memcpy(llc->laddr.mac, addr->sllc_mac, IFHWADDRLEN);
 335         memcpy(&llc->addr, addr, sizeof(llc->addr));
 336         /* assign new connection to its SAP */
 337         llc_sap_add_socket(sap, sk);
 338         sock_reset_flag(sk, SOCK_ZAPPED);
 339         rc = 0;
 340 out:
 341         return rc;
 342 }
 343
 344 /**
 345  *      llc_ui_shutdown - shutdown a connect llc2 socket.
 346  *      @sock: Socket to shutdown.
 347  *      @how: What part of the socket to shutdown.
 348  *
 349  *      Shutdown a connected llc2 socket. Currently this function only supports
 350  *      shutting down both sends and receives (2), we could probably make this
 351  *      function such that a user can shutdown only half the connection but not
 352  *      right now.
 353  *      Returns: 0 upon success, negative otherwise.
 354  */
 355 static int llc_ui_shutdown(struct socket *sock, int how)
 356 {
 357         struct sock *sk = sock->sk;
 358         int rc = -ENOTCONN;
 359
 360         lock_sock(sk);
 361         if (unlikely(sk->sk_state != TCP_ESTABLISHED))
 362                 goto out;
 363         rc = -EINVAL;
 364         if (how != 2)
 365                 goto out;
 366         rc = llc_send_disc(sk);
 367         if (!rc)
 368                 rc = llc_ui_wait_for_disc(sk, sk->sk_rcvtimeo);
 369         /* Wake up anyone sleeping in poll */
 370         sk->sk_state_change(sk);
 371 out:
 372         release_sock(sk);
 373         return rc;
 374 }
 375
 376 /**
 377  *      llc_ui_connect - Connect to a remote llc2 mac + sap.
 378  *      @sock: Socket which will be connected to the remote destination.
 379  *      @uaddr: Remote and possibly the local address of the new connection.
 380  *      @addrlen: Size of uaddr structure.
 381  *      @flags: Operational flags specified by the user.
 382  *
 383  *      Connect to a remote llc2 mac + sap. The caller must specify the
 384  *      destination mac and address to connect to. If the user hasn't previously
 385  *      called bind(2) with a smac the address of the first interface of the
 386  *      specified arp type will be used.
 387  *      This function will autobind if user did not previously call bind.
 388  *      Returns: 0 upon success, negative otherwise.
 389  */
 390 static int llc_ui_connect(struct socket *sock, struct sockaddr *uaddr,
 391                           int addrlen, int flags)
 392 {
 393         struct sock *sk = sock->sk;
 394         struct llc_sock *llc = llc_sk(sk);
 395         struct sockaddr_llc *addr = (struct sockaddr_llc *)uaddr;
 396         int rc = -EINVAL;
 397
 398         lock_sock(sk);
 399         if (unlikely(addrlen != sizeof(*addr)))
 400                 goto out;
 401         rc = -EAFNOSUPPORT;
 402         if (unlikely(addr->sllc_family != AF_LLC))
 403                 goto out;
 404         if (unlikely(sk->sk_type != SOCK_STREAM))
 405                 goto out;
 406         rc = -EALREADY;
 407         if (unlikely(sock->state == SS_CONNECTING))
 408                 goto out;
 409         /* bind connection to sap if user hasn't done it. */
 410         if (sock_flag(sk, SOCK_ZAPPED)) {
 411                 /* bind to sap with null dev, exclusive */
 412                 rc = llc_ui_autobind(sock, addr);
 413                 if (rc)
 414                         goto out;
 415                 llc->daddr.lsap = addr->sllc_sap;
 416                 memcpy(llc->daddr.mac, addr->sllc_mac, IFHWADDRLEN);
 417         }
 418         sock->state = SS_CONNECTING;
 419         sk->sk_state   = TCP_SYN_SENT;
 420         llc->link   = llc_ui_next_link_no(llc->sap->laddr.lsap);
 421         rc = llc_establish_connection(sk, llc->dev->dev_addr,
 422                                       addr->sllc_mac, addr->sllc_sap);
 423         if (rc) {
 424                 dprintk("%s: llc_ui_send_conn failed :-(\n", __FUNCTION__);
 425                 sock->state  = SS_UNCONNECTED;
 426                 sk->sk_state = TCP_CLOSE;
 427                 goto out;
 428         }
 429
 430         if (sk->sk_state == TCP_SYN_SENT) {
 431                 const long timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
 432
 433                 if (!timeo || !llc_ui_wait_for_conn(sk, timeo))
 434                         goto out;
 435
 436                 rc = sock_intr_errno(timeo);
 437                 if (signal_pending(current))
 438                         goto out;
 439         }
 440
 441         if (sk->sk_state == TCP_CLOSE)
 442                 goto sock_error;
 443
 444         sock->state = SS_CONNECTED;
 445         rc = 0;
 446 out:
 447         release_sock(sk);
 448         return rc;
 449 sock_error:
 450         rc = sock_error(sk) ? : -ECONNABORTED;
 451         sock->state = SS_UNCONNECTED;
 452         goto out;
 453 }
 454
 455 /**
 456  *      llc_ui_listen - allow a normal socket to accept incoming connections
 457  *      @sock: Socket to allow incoming connections on.
 458  *      @backlog: Number of connections to queue.
 459  *
 460  *      Allow a normal socket to accept incoming connections.
 461  *      Returns 0 upon success, negative otherwise.
 462  */
 463 static int llc_ui_listen(struct socket *sock, int backlog)
 464 {
 465         struct sock *sk = sock->sk;
 466         int rc = -EINVAL;
 467
 468         lock_sock(sk);
 469         if (unlikely(sock->state != SS_UNCONNECTED))
 470                 goto out;
 471         rc = -EOPNOTSUPP;
 472         if (unlikely(sk->sk_type != SOCK_STREAM))
 473                 goto out;
 474         rc = -EAGAIN;
 475         if (sock_flag(sk, SOCK_ZAPPED))
 476                 goto out;
 477         rc = 0;
 478         if (!(unsigned)backlog) /* BSDism */
 479                 backlog = 1;
 480         sk->sk_max_ack_backlog = backlog;
 481         if (sk->sk_state != TCP_LISTEN) {
 482                 sk->sk_ack_backlog = 0;
 483                 sk->sk_state       = TCP_LISTEN;
 484         }
 485         sk->sk_socket->flags |= __SO_ACCEPTCON;
 486 out:
 487         release_sock(sk);
 488         return rc;
 489 }
 490
 491 static int llc_ui_wait_for_disc(struct sock *sk, long timeout)
 492 {
 493         DEFINE_WAIT(wait);
 494         int rc = 0;
 495
 496         while (1) {
 497                 prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
 498                 if (sk_wait_event(sk, &timeout, sk->sk_state == TCP_CLOSE))
 499                         break;
 500                 rc = -ERESTARTSYS;
 501                 if (signal_pending(current))
 502                         break;
 503                 rc = -EAGAIN;
 504                 if (!timeout)
 505                         break;
 506                 rc = 0;
 507         }
 508         finish_wait(sk->sk_sleep, &wait);
 509         return rc;
 510 }
 511
 512 static int llc_ui_wait_for_conn(struct sock *sk, long timeout)
 513 {
 514         DEFINE_WAIT(wait);
 515
 516         while (1) {
 517                 prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
 518                 if (sk_wait_event(sk, &timeout, sk->sk_state != TCP_SYN_SENT))
 519                         break;
 520                 if (signal_pending(current) || !timeout)
 521                         break;
 522         }
 523         finish_wait(sk->sk_sleep, &wait);
 524         return timeout;
 525 }
 526
 527 static int llc_ui_wait_for_data(struct sock *sk, long timeout)
 528 {
 529         DEFINE_WAIT(wait);
 530         int rc = 0;
 531
 532         while (1) {
 533                 prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
 534                 if (sk_wait_event(sk, &timeout,
 535                                   (sk->sk_shutdown & RCV_SHUTDOWN) ||
 536                                   (!skb_queue_empty(&sk->sk_receive_queue))))
 537                         break;
 538                 rc = -ERESTARTSYS;
 539                 if (signal_pending(current))
 540                         break;
 541                 rc = -EAGAIN;
 542                 if (!timeout)
 543                         break;
 544                 rc = 0;
 545         }
 546         finish_wait(sk->sk_sleep, &wait);
 547         return rc;
 548 }
 549
 550 static int llc_ui_wait_for_busy_core(struct sock *sk, long timeout)
 551 {
 552         DEFINE_WAIT(wait);
 553         struct llc_sock *llc = llc_sk(sk);
 554         int rc;
 555
 556         while (1) {
 557                 prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
 558                 rc = 0;
 559                 if (sk_wait_event(sk, &timeout,
 560                                   (sk->sk_shutdown & RCV_SHUTDOWN) ||
 561                                   (!llc_data_accept_state(llc->state) &&
 562                                    !llc->p_flag)))
 563                         break;
 564                 rc = -ERESTARTSYS;
 565                 if (signal_pending(current))
 566                         break;
 567                 rc = -EAGAIN;
 568                 if (!timeout)
 569                         break;
 570         }
 571         finish_wait(sk->sk_sleep, &wait);
 572         return rc;
 573 }
 574
 575 /**
 576  *      llc_ui_accept - accept a new incoming connection.
 577  *      @sock: Socket which connections arrive on.
 578  *      @newsock: Socket to move incoming connection to.
 579  *      @flags: User specified operational flags.
 580  *
 581  *      Accept a new incoming connection.
 582  *      Returns 0 upon success, negative otherwise.
 583  */
 584 static int llc_ui_accept(struct socket *sock, struct socket *newsock, int flags)
 585 {
 586         struct sock *sk = sock->sk, *newsk;
 587         struct llc_sock *llc, *newllc;
 588         struct sk_buff *skb;
 589         int rc = -EOPNOTSUPP;
 590
 591         dprintk("%s: accepting on %02X\n", __FUNCTION__,
 592                 llc_sk(sk)->laddr.lsap);
 593         lock_sock(sk);
 594         if (unlikely(sk->sk_type != SOCK_STREAM))
 595                 goto out;
 596         rc = -EINVAL;
 597         if (unlikely(sock->state != SS_UNCONNECTED ||
 598                      sk->sk_state != TCP_LISTEN))
 599                 goto out;
 600         /* wait for a connection to arrive. */
 601         if (skb_queue_empty(&sk->sk_receive_queue)) {
 602                 rc = llc_ui_wait_for_data(sk, sk->sk_rcvtimeo);
 603                 if (rc)
 604                         goto out;
 605         }
 606         dprintk("%s: got a new connection on %02X\n", __FUNCTION__,
 607                 llc_sk(sk)->laddr.lsap);
 608         skb = skb_dequeue(&sk->sk_receive_queue);
 609         rc = -EINVAL;
 610         if (!skb->sk)
 611                 goto frees;
 612         rc = 0;
 613         newsk = skb->sk;
 614         /* attach connection to a new socket. */
 615         llc_ui_sk_init(newsock, newsk);
 616         sock_reset_flag(newsk, SOCK_ZAPPED);
 617         newsk->sk_state         = TCP_ESTABLISHED;
 618         newsock->state          = SS_CONNECTED;
 619         llc                     = llc_sk(sk);
 620         newllc                  = llc_sk(newsk);
 621         memcpy(&newllc->addr, &llc->addr, sizeof(newllc->addr));
 622         newllc->link = llc_ui_next_link_no(newllc->laddr.lsap);
 623
 624         /* put original socket back into a clean listen state. */
 625         sk->sk_state = TCP_LISTEN;
 626         sk->sk_ack_backlog--;
 627         skb->sk = NULL;
 628         dprintk("%s: ok success on %02X, client on %02X\n", __FUNCTION__,
 629                 llc_sk(sk)->addr.sllc_sap, newllc->daddr.lsap);
 630 frees:
 631         kfree_skb(skb);
 632 out:
 633         release_sock(sk);
 634         return rc;
 635 }
 636
 637 /**
 638  *      llc_ui_recvmsg - copy received data to the socket user.
 639  *      @sock: Socket to copy data from.
 640  *      @msg: Various user space related information.
 641  *      @size: Size of user buffer.
 642  *      @flags: User specified flags.
 643  *
 644  *      Copy received data to the socket user.
 645  *      Returns non-negative upon success, negative otherwise.
 646  */
 647 static int llc_ui_recvmsg(struct kiocb *iocb, struct socket *sock,
 648                           struct msghdr *msg, size_t size, int flags)
 649 {
 650         struct sock *sk = sock->sk;
 651         struct sockaddr_llc *uaddr = (struct sockaddr_llc *)msg->msg_name;
 652         struct sk_buff *skb;
 653         size_t copied = 0;
 654         int rc = -ENOMEM;
 655         int noblock = flags & MSG_DONTWAIT;
 656
 657         dprintk("%s: receiving in %02X from %02X\n", __FUNCTION__,
 658                 llc_sk(sk)->laddr.lsap, llc_sk(sk)->daddr.lsap);
 659         lock_sock(sk);
 660         if (skb_queue_empty(&sk->sk_receive_queue)) {
 661                 rc = llc_ui_wait_for_data(sk, sock_rcvtimeo(sk, noblock));
 662                 if (rc)
 663                         goto out;
 664         }
 665         skb = skb_dequeue(&sk->sk_receive_queue);
 666         if (!skb) /* shutdown */
 667                 goto out;
 668         copied = skb->len;
 669         if (copied > size)
 670                 copied = size;
 671         rc = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
 672         if (rc)
 673                 goto dgram_free;
 674         if (skb->len > copied) {
 675                 skb_pull(skb, copied);
 676                 skb_queue_head(&sk->sk_receive_queue, skb);
 677         }
 678         if (uaddr)
 679                 memcpy(uaddr, llc_ui_skb_cb(skb), sizeof(*uaddr));
 680         msg->msg_namelen = sizeof(*uaddr);
 681         if (!skb->next) {
 682 dgram_free:
 683                 kfree_skb(skb);
 684         }
 685 out:
 686         release_sock(sk);
 687         return rc ? : copied;
 688 }
 689
 690 /**
 691  *      llc_ui_sendmsg - Transmit data provided by the socket user.
 692  *      @sock: Socket to transmit data from.
 693  *      @msg: Various user related information.
 694  *      @len: Length of data to transmit.
 695  *
 696  *      Transmit data provided by the socket user.
 697  *      Returns non-negative upon success, negative otherwise.
 698  */
 699 static int llc_ui_sendmsg(struct kiocb *iocb, struct socket *sock,
 700                           struct msghdr *msg, size_t len)
 701 {
 702         struct sock *sk = sock->sk;
 703         struct llc_sock *llc = llc_sk(sk);
 704         struct sockaddr_llc *addr = (struct sockaddr_llc *)msg->msg_name;
 705         int flags = msg->msg_flags;
 706         int noblock = flags & MSG_DONTWAIT;
 707         struct sk_buff *skb;
 708         size_t size = 0;
 709         int rc = -EINVAL, copied = 0, hdrlen;
 710
 711         dprintk("%s: sending from %02X to %02X\n", __FUNCTION__,
 712                 llc->laddr.lsap, llc->daddr.lsap);
 713         lock_sock(sk);
 714         if (addr) {
 715                 if (msg->msg_namelen < sizeof(*addr))
 716                         goto release;
 717         } else {
 718                 if (llc_ui_addr_null(&llc->addr))
 719                         goto release;
 720                 addr = &llc->addr;
 721         }
 722         /* must bind connection to sap if user hasn't done it. */
 723         if (sock_flag(sk, SOCK_ZAPPED)) {
 724                 /* bind to sap with null dev, exclusive. */
 725                 rc = llc_ui_autobind(sock, addr);
 726                 if (rc)
 727                         goto release;
 728         }
 729         hdrlen = llc->dev->hard_header_len + llc_ui_header_len(sk, addr);
 730         size = hdrlen + len;
 731         if (size > llc->dev->mtu)
 732                 size = llc->dev->mtu;
 733         copied = size - hdrlen;
 734         release_sock(sk);
 735         skb = sock_alloc_send_skb(sk, size, noblock, &rc);
 736         lock_sock(sk);
 737         if (!skb)
 738                 goto release;
 739         skb->sk       = sk;
 740         skb->dev      = llc->dev;
 741         skb->protocol = llc_proto_type(addr->sllc_arphrd);
 742         skb_reserve(skb, hdrlen);
 743         rc = memcpy_fromiovec(skb_put(skb, copied), msg->msg_iov, copied);
 744         if (rc)
 745                 goto out;
 746         if (sk->sk_type == SOCK_DGRAM || addr->sllc_ua) {
 747                 llc_build_and_send_ui_pkt(llc->sap, skb, addr->sllc_mac,
 748                                           addr->sllc_sap);
 749                 goto out;
 750         }
 751         if (addr->sllc_test) {
 752                 llc_build_and_send_test_pkt(llc->sap, skb, addr->sllc_mac,
 753                                             addr->sllc_sap);
 754                 goto out;
 755         }
 756         if (addr->sllc_xid) {
 757                 llc_build_and_send_xid_pkt(llc->sap, skb, addr->sllc_mac,
 758                                            addr->sllc_sap);
 759                 goto out;
 760         }
 761         rc = -ENOPROTOOPT;
 762         if (!(sk->sk_type == SOCK_STREAM && !addr->sllc_ua))
 763                 goto out;
 764         rc = llc_ui_send_data(sk, skb, noblock);
 765         if (rc)
 766                 dprintk("%s: llc_ui_send_data failed: %d\n", __FUNCTION__, rc);
 767 out:
 768         if (rc)
 769                 kfree_skb(skb);
 770 release:
 771         if (rc)
 772                 dprintk("%s: failed sending from %02X to %02X: %d\n",
 773                         __FUNCTION__, llc->laddr.lsap, llc->daddr.lsap, rc);
 774         release_sock(sk);
 775         return rc ? : copied;
 776 }
 777
 778 /**
 779  *      llc_ui_getname - return the address info of a socket
 780  *      @sock: Socket to get address of.
 781  *      @uaddr: Address structure to return information.
 782  *      @uaddrlen: Length of address structure.
 783  *      @peer: Does user want local or remote address information.
 784  *
 785  *      Return the address information of a socket.
 786  */
 787 static int llc_ui_getname(struct socket *sock, struct sockaddr *uaddr,
 788                           int *uaddrlen, int peer)
 789 {
 790         struct sockaddr_llc sllc;
 791         struct sock *sk = sock->sk;
 792         struct llc_sock *llc = llc_sk(sk);
 793         int rc = 0;
 794
 795         lock_sock(sk);
 796         if (sock_flag(sk, SOCK_ZAPPED))
 797                 goto out;
 798         *uaddrlen = sizeof(sllc);
 799         memset(uaddr, 0, *uaddrlen);
 800         if (peer) {
 801                 rc = -ENOTCONN;
 802                 if (sk->sk_state != TCP_ESTABLISHED)
 803                         goto out;
 804                 if(llc->dev)
 805                         sllc.sllc_arphrd = llc->dev->type;
 806                 sllc.sllc_sap = llc->daddr.lsap;
 807                 memcpy(&sllc.sllc_mac, &llc->daddr.mac, IFHWADDRLEN);
 808         } else {
 809                 rc = -EINVAL;
 810                 if (!llc->sap)
 811                         goto out;
 812                 sllc.sllc_sap = llc->sap->laddr.lsap;
 813
 814                 if (llc->dev) {
 815                         sllc.sllc_arphrd = llc->dev->type;
 816                         memcpy(&sllc.sllc_mac, &llc->dev->dev_addr,
 817                                IFHWADDRLEN);
 818                 }
 819         }
 820         rc = 0;
 821         sllc.sllc_family = AF_LLC;
 822         memcpy(uaddr, &sllc, sizeof(sllc));
 823 out:
 824         release_sock(sk);
 825         return rc;
 826 }
 827
 828 /**
 829  *      llc_ui_ioctl - io controls for PF_LLC
 830  *      @sock: Socket to get/set info
 831  *      @cmd: command
 832  *      @arg: optional argument for cmd
 833  *
 834  *      get/set info on llc sockets
 835  */
 836 static int llc_ui_ioctl(struct socket *sock, unsigned int cmd,
 837                         unsigned long arg)
 838 {
 839         return dev_ioctl(cmd, (void __user *)arg);
 840 }
 841
 842 /**
 843  *      llc_ui_setsockopt - set various connection specific parameters.
 844  *      @sock: Socket to set options on.
 845  *      @level: Socket level user is requesting operations on.
 846  *      @optname: Operation name.
 847  *      @optval User provided operation data.
 848  *      @optlen: Length of optval.
 849  *
 850  *      Set various connection specific parameters.
 851  */
 852 static int llc_ui_setsockopt(struct socket *sock, int level, int optname,
 853                              char __user *optval, int optlen)
 854 {
 855         struct sock *sk = sock->sk;
 856         struct llc_sock *llc = llc_sk(sk);
 857         int rc = -EINVAL, opt;
 858
 859         lock_sock(sk);
 860         if (unlikely(level != SOL_LLC || optlen != sizeof(int)))
 861                 goto out;
 862         rc = get_user(opt, (int __user *)optval);
 863         if (rc)
 864                 goto out;
 865         rc = -EINVAL;
 866         switch (optname) {
 867         case LLC_OPT_RETRY:
 868                 if (opt > LLC_OPT_MAX_RETRY)
 869                         goto out;
 870                 llc->n2 = opt;
 871                 break;
 872         case LLC_OPT_SIZE:
 873                 if (opt > LLC_OPT_MAX_SIZE)
 874                         goto out;
 875                 llc->n1 = opt;
 876                 break;
 877         case LLC_OPT_ACK_TMR_EXP:
 878                 if (opt > LLC_OPT_MAX_ACK_TMR_EXP)
 879                         goto out;
 880                 llc->ack_timer.expire = opt * HZ;
 881                 break;
 882         case LLC_OPT_P_TMR_EXP:
 883                 if (opt > LLC_OPT_MAX_P_TMR_EXP)
 884                         goto out;
 885                 llc->pf_cycle_timer.expire = opt * HZ;
 886                 break;
 887         case LLC_OPT_REJ_TMR_EXP:
 888                 if (opt > LLC_OPT_MAX_REJ_TMR_EXP)
 889                         goto out;
 890                 llc->rej_sent_timer.expire = opt * HZ;
 891                 break;
 892         case LLC_OPT_BUSY_TMR_EXP:
 893                 if (opt > LLC_OPT_MAX_BUSY_TMR_EXP)
 894                         goto out;
 895                 llc->busy_state_timer.expire = opt * HZ;
 896                 break;
 897         case LLC_OPT_TX_WIN:
 898                 if (opt > LLC_OPT_MAX_WIN)
 899                         goto out;
 900                 llc->k = opt;
 901                 break;
 902         case LLC_OPT_RX_WIN:
 903                 if (opt > LLC_OPT_MAX_WIN)
 904                         goto out;
 905                 llc->rw = opt;
 906                 break;
 907         default:
 908                 rc = -ENOPROTOOPT;
 909                 goto out;
 910         }
 911         rc = 0;
 912 out:
 913         release_sock(sk);
 914         return rc;
 915 }
 916
 917 /**
 918  *      llc_ui_getsockopt - get connection specific socket info
 919  *      @sock: Socket to get information from.
 920  *      @level: Socket level user is requesting operations on.
 921  *      @optname: Operation name.
 922  *      @optval: Variable to return operation data in.
 923  *      @optlen: Length of optval.
 924  *
 925  *      Get connection specific socket information.
 926  */
 927 static int llc_ui_getsockopt(struct socket *sock, int level, int optname,
 928                              char __user *optval, int __user *optlen)
 929 {
 930         struct sock *sk = sock->sk;
 931         struct llc_sock *llc = llc_sk(sk);
 932         int val = 0, len = 0, rc = -EINVAL;
 933
 934         lock_sock(sk);
 935         if (unlikely(level != SOL_LLC))
 936                 goto out;
 937         rc = get_user(len, optlen);
 938         if (rc)
 939                 goto out;
 940         rc = -EINVAL;
 941         if (len != sizeof(int))
 942                 goto out;
 943         switch (optname) {
 944         case LLC_OPT_RETRY:
 945                 val = llc->n2;                                  break;
 946         case LLC_OPT_SIZE:
 947                 val = llc->n1;                                  break;
 948         case LLC_OPT_ACK_TMR_EXP:
 949                 val = llc->ack_timer.expire / HZ;               break;
 950         case LLC_OPT_P_TMR_EXP:
 951                 val = llc->pf_cycle_timer.expire / HZ;          break;
 952         case LLC_OPT_REJ_TMR_EXP:
 953                 val = llc->rej_sent_timer.expire / HZ;          break;
 954         case LLC_OPT_BUSY_TMR_EXP:
 955                 val = llc->busy_state_timer.expire / HZ;        break;
 956         case LLC_OPT_TX_WIN:
 957                 val = llc->k;                           break;
 958         case LLC_OPT_RX_WIN:
 959                 val = llc->rw;                          break;
 960         default:
 961                 rc = -ENOPROTOOPT;
 962                 goto out;
 963         }
 964         rc = 0;
 965         if (put_user(len, optlen) || copy_to_user(optval, &val, len))
 966                 rc = -EFAULT;
 967 out:
 968         release_sock(sk);
 969         return rc;
 970 }
 971
 972 static struct net_proto_family llc_ui_family_ops = {
 973         .family = PF_LLC,
 974         .create = llc_ui_create,
 975         .owner  = THIS_MODULE,
 976 };
 977
 978 static struct proto_ops llc_ui_ops = {
 979         .family      = PF_LLC,
 980         .owner       = THIS_MODULE,
 981         .release     = llc_ui_release,
 982         .bind        = llc_ui_bind,
 983         .connect     = llc_ui_connect,
 984         .socketpair  = sock_no_socketpair,
 985         .accept      = llc_ui_accept,
 986         .getname     = llc_ui_getname,
 987         .poll        = datagram_poll,
 988         .ioctl       = llc_ui_ioctl,
 989         .listen      = llc_ui_listen,
 990         .shutdown    = llc_ui_shutdown,
 991         .setsockopt  = llc_ui_setsockopt,
 992         .getsockopt  = llc_ui_getsockopt,
 993         .sendmsg     = llc_ui_sendmsg,
 994         .recvmsg     = llc_ui_recvmsg,
 995         .mmap        = sock_no_mmap,
 996         .sendpage    = sock_no_sendpage,
 997 };
 998
 999 extern void llc_sap_handler(struct llc_sap *sap, struct sk_buff *skb);
1000 extern void llc_conn_handler(struct llc_sap *sap, struct sk_buff *skb);
1001
1002 static char llc_proc_err_msg[] __initdata =
1003         KERN_CRIT "LLC: Unable to register the proc_fs entries\n";
1004 static char llc_sysctl_err_msg[] __initdata =
1005         KERN_CRIT "LLC: Unable to register the sysctl entries\n";
1006 static char llc_sock_err_msg[] __initdata =
1007         KERN_CRIT "LLC: Unable to register the network family\n";
1008
1009 static int __init llc2_init(void)
1010 {
1011         int rc = proto_register(&llc_proto, 0);
1012
1013         if (rc != 0)
1014                 goto out;
1015
1016         llc_build_offset_table();
1017         llc_station_init();
1018         llc_ui_sap_last_autoport = LLC_SAP_DYN_START;
1019         rc = llc_proc_init();
1020         if (rc != 0) {
1021                 printk(llc_proc_err_msg);
1022                 goto out_unregister_llc_proto;
1023         }
1024         rc = llc_sysctl_init();
1025         if (rc) {
1026                 printk(llc_sysctl_err_msg);
1027                 goto out_proc;
1028         }
1029         rc = sock_register(&llc_ui_family_ops);
1030         if (rc) {
1031                 printk(llc_sock_err_msg);
1032                 goto out_sysctl;
1033         }
1034         llc_add_pack(LLC_DEST_SAP, llc_sap_handler);
1035         llc_add_pack(LLC_DEST_CONN, llc_conn_handler);
1036 out:
1037         return rc;
1038 out_sysctl:
1039         llc_sysctl_exit();
1040 out_proc:
1041         llc_proc_exit();
1042 out_unregister_llc_proto:
1043         proto_unregister(&llc_proto);
1044         goto out;
1045 }
1046
1047 static void __exit llc2_exit(void)
1048 {
1049         llc_station_exit();
1050         llc_remove_pack(LLC_DEST_SAP);
1051         llc_remove_pack(LLC_DEST_CONN);
1052         sock_unregister(PF_LLC);
1053         llc_proc_exit();
1054         llc_sysctl_exit();
1055         proto_unregister(&llc_proto);
1056 }
1057
1058 module_init(llc2_init);
1059 module_exit(llc2_exit);
1060
1061 MODULE_LICENSE("GPL");
1062 MODULE_AUTHOR("Procom 1997, Jay Schullist 2001, Arnaldo C. Melo 2001-2003");
1063 MODULE_DESCRIPTION("IEEE 802.2 PF_LLC support");
1064 MODULE_ALIAS_NETPROTO(PF_LLC);