Pileus Git - ~andy/linux/blob - net/decnet/af_decnet.c

   1
   2 /*
   3  * DECnet       An implementation of the DECnet protocol suite for the LINUX
   4  *              operating system.  DECnet is implemented using the  BSD Socket
   5  *              interface as the means of communication with the user level.
   6  *
   7  *              DECnet Socket Layer Interface
   8  *
   9  * Authors:     Eduardo Marcelo Serrat <emserrat@geocities.com>
  10  *              Patrick Caulfield <patrick@pandh.demon.co.uk>
  11  *
  12  * Changes:
  13  *        Steve Whitehouse: Copied from Eduardo Serrat and Patrick Caulfield's
  14  *                          version of the code. Original copyright preserved
  15  *                          below.
  16  *        Steve Whitehouse: Some bug fixes, cleaning up some code to make it
  17  *                          compatible with my routing layer.
  18  *        Steve Whitehouse: Merging changes from Eduardo Serrat and Patrick
  19  *                          Caulfield.
  20  *        Steve Whitehouse: Further bug fixes, checking module code still works
  21  *                          with new routing layer.
  22  *        Steve Whitehouse: Additional set/get_sockopt() calls.
  23  *        Steve Whitehouse: Fixed TIOCINQ ioctl to be same as Eduardo's new
  24  *                          code.
  25  *        Steve Whitehouse: recvmsg() changed to try and behave in a POSIX like
  26  *                          way. Didn't manage it entirely, but its better.
  27  *        Steve Whitehouse: ditto for sendmsg().
  28  *        Steve Whitehouse: A selection of bug fixes to various things.
  29  *        Steve Whitehouse: Added TIOCOUTQ ioctl.
  30  *        Steve Whitehouse: Fixes to username2sockaddr & sockaddr2username.
  31  *        Steve Whitehouse: Fixes to connect() error returns.
  32  *       Patrick Caulfield: Fixes to delayed acceptance logic.
  33  *         David S. Miller: New socket locking
  34  *        Steve Whitehouse: Socket list hashing/locking
  35  *         Arnaldo C. Melo: use capable, not suser
  36  *        Steve Whitehouse: Removed unused code. Fix to use sk->allocation
  37  *                          when required.
  38  *       Patrick Caulfield: /proc/net/decnet now has object name/number
  39  *        Steve Whitehouse: Fixed local port allocation, hashed sk list
  40  *          Matthew Wilcox: Fixes for dn_ioctl()
  41  *        Steve Whitehouse: New connect/accept logic to allow timeouts and
  42  *                          prepare for sendpage etc.
  43  */
  44
  45
  46 /******************************************************************************
  47     (c) 1995-1998 E.M. Serrat           emserrat@geocities.com
  48
  49     This program is free software; you can redistribute it and/or modify
  50     it under the terms of the GNU General Public License as published by
  51     the Free Software Foundation; either version 2 of the License, or
  52     any later version.
  53
  54     This program is distributed in the hope that it will be useful,
  55     but WITHOUT ANY WARRANTY; without even the implied warranty of
  56     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  57     GNU General Public License for more details.
  58
  59 HISTORY:
  60
  61 Version           Kernel     Date       Author/Comments
  62 -------           ------     ----       ---------------
  63 Version 0.0.1     2.0.30    01-dic-97   Eduardo Marcelo Serrat
  64                                         (emserrat@geocities.com)
  65
  66                                         First Development of DECnet Socket La-
  67                                         yer for Linux. Only supports outgoing
  68                                         connections.
  69
  70 Version 0.0.2     2.1.105   20-jun-98   Patrick J. Caulfield
  71                                         (patrick@pandh.demon.co.uk)
  72
  73                                         Port to new kernel development version.
  74
  75 Version 0.0.3     2.1.106   25-jun-98   Eduardo Marcelo Serrat
  76                                         (emserrat@geocities.com)
  77                                         _
  78                                         Added support for incoming connections
  79                                         so we can start developing server apps
  80                                         on Linux.
  81                                         -
  82                                         Module Support
  83 Version 0.0.4     2.1.109   21-jul-98   Eduardo Marcelo Serrat
  84                                        (emserrat@geocities.com)
  85                                        _
  86                                         Added support for X11R6.4. Now we can
  87                                         use DECnet transport for X on Linux!!!
  88                                        -
  89 Version 0.0.5    2.1.110   01-aug-98   Eduardo Marcelo Serrat
  90                                        (emserrat@geocities.com)
  91                                        Removed bugs on flow control
  92                                        Removed bugs on incoming accessdata
  93                                        order
  94                                        -
  95 Version 0.0.6    2.1.110   07-aug-98   Eduardo Marcelo Serrat
  96                                        dn_recvmsg fixes
  97
  98                                         Patrick J. Caulfield
  99                                        dn_bind fixes
 100 *******************************************************************************/
 101
 102 #include <linux/module.h>
 103 #include <linux/errno.h>
 104 #include <linux/types.h>
 105 #include <linux/slab.h>
 106 #include <linux/socket.h>
 107 #include <linux/in.h>
 108 #include <linux/kernel.h>
 109 #include <linux/sched.h>
 110 #include <linux/timer.h>
 111 #include <linux/string.h>
 112 #include <linux/sockios.h>
 113 #include <linux/net.h>
 114 #include <linux/netdevice.h>
 115 #include <linux/inet.h>
 116 #include <linux/route.h>
 117 #include <linux/netfilter.h>
 118 #include <linux/seq_file.h>
 119 #include <net/sock.h>
 120 #include <net/tcp_states.h>
 121 #include <net/flow.h>
 122 #include <asm/ioctls.h>
 123 #include <linux/capability.h>
 124 #include <linux/mm.h>
 125 #include <linux/interrupt.h>
 126 #include <linux/proc_fs.h>
 127 #include <linux/stat.h>
 128 #include <linux/init.h>
 129 #include <linux/poll.h>
 130 #include <net/net_namespace.h>
 131 #include <net/neighbour.h>
 132 #include <net/dst.h>
 133 #include <net/fib_rules.h>
 134 #include <net/dn.h>
 135 #include <net/dn_nsp.h>
 136 #include <net/dn_dev.h>
 137 #include <net/dn_route.h>
 138 #include <net/dn_fib.h>
 139 #include <net/dn_neigh.h>
 140
 141 struct dn_sock {
 142         struct sock sk;
 143         struct dn_scp scp;
 144 };
 145
 146 static void dn_keepalive(struct sock *sk);
 147
 148 #define DN_SK_HASH_SHIFT 8
 149 #define DN_SK_HASH_SIZE (1 << DN_SK_HASH_SHIFT)
 150 #define DN_SK_HASH_MASK (DN_SK_HASH_SIZE - 1)
 151
 152
 153 static const struct proto_ops dn_proto_ops;
 154 static DEFINE_RWLOCK(dn_hash_lock);
 155 static struct hlist_head dn_sk_hash[DN_SK_HASH_SIZE];
 156 static struct hlist_head dn_wild_sk;
 157 static atomic_long_t decnet_memory_allocated;
 158
 159 static int __dn_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen, int flags);
 160 static int __dn_getsockopt(struct socket *sock, int level, int optname, char __user *optval, int __user *optlen, int flags);
 161
 162 static struct hlist_head *dn_find_list(struct sock *sk)
 163 {
 164         struct dn_scp *scp = DN_SK(sk);
 165
 166         if (scp->addr.sdn_flags & SDF_WILD)
 167                 return hlist_empty(&dn_wild_sk) ? &dn_wild_sk : NULL;
 168
 169         return &dn_sk_hash[le16_to_cpu(scp->addrloc) & DN_SK_HASH_MASK];
 170 }
 171
 172 /*
 173  * Valid ports are those greater than zero and not already in use.
 174  */
 175 static int check_port(__le16 port)
 176 {
 177         struct sock *sk;
 178
 179         if (port == 0)
 180                 return -1;
 181
 182         sk_for_each(sk, &dn_sk_hash[le16_to_cpu(port) & DN_SK_HASH_MASK]) {
 183                 struct dn_scp *scp = DN_SK(sk);
 184                 if (scp->addrloc == port)
 185                         return -1;
 186         }
 187         return 0;
 188 }
 189
 190 static unsigned short port_alloc(struct sock *sk)
 191 {
 192         struct dn_scp *scp = DN_SK(sk);
 193 static unsigned short port = 0x2000;
 194         unsigned short i_port = port;
 195
 196         while(check_port(cpu_to_le16(++port)) != 0) {
 197                 if (port == i_port)
 198                         return 0;
 199         }
 200
 201         scp->addrloc = cpu_to_le16(port);
 202
 203         return 1;
 204 }
 205
 206 /*
 207  * Since this is only ever called from user
 208  * level, we don't need a write_lock() version
 209  * of this.
 210  */
 211 static int dn_hash_sock(struct sock *sk)
 212 {
 213         struct dn_scp *scp = DN_SK(sk);
 214         struct hlist_head *list;
 215         int rv = -EUSERS;
 216
 217         BUG_ON(sk_hashed(sk));
 218
 219         write_lock_bh(&dn_hash_lock);
 220
 221         if (!scp->addrloc && !port_alloc(sk))
 222                 goto out;
 223
 224         rv = -EADDRINUSE;
 225         if ((list = dn_find_list(sk)) == NULL)
 226                 goto out;
 227
 228         sk_add_node(sk, list);
 229         rv = 0;
 230 out:
 231         write_unlock_bh(&dn_hash_lock);
 232         return rv;
 233 }
 234
 235 static void dn_unhash_sock(struct sock *sk)
 236 {
 237         write_lock(&dn_hash_lock);
 238         sk_del_node_init(sk);
 239         write_unlock(&dn_hash_lock);
 240 }
 241
 242 static void dn_unhash_sock_bh(struct sock *sk)
 243 {
 244         write_lock_bh(&dn_hash_lock);
 245         sk_del_node_init(sk);
 246         write_unlock_bh(&dn_hash_lock);
 247 }
 248
 249 static struct hlist_head *listen_hash(struct sockaddr_dn *addr)
 250 {
 251         int i;
 252         unsigned int hash = addr->sdn_objnum;
 253
 254         if (hash == 0) {
 255                 hash = addr->sdn_objnamel;
 256                 for(i = 0; i < le16_to_cpu(addr->sdn_objnamel); i++) {
 257                         hash ^= addr->sdn_objname[i];
 258                         hash ^= (hash << 3);
 259                 }
 260         }
 261
 262         return &dn_sk_hash[hash & DN_SK_HASH_MASK];
 263 }
 264
 265 /*
 266  * Called to transform a socket from bound (i.e. with a local address)
 267  * into a listening socket (doesn't need a local port number) and rehashes
 268  * based upon the object name/number.
 269  */
 270 static void dn_rehash_sock(struct sock *sk)
 271 {
 272         struct hlist_head *list;
 273         struct dn_scp *scp = DN_SK(sk);
 274
 275         if (scp->addr.sdn_flags & SDF_WILD)
 276                 return;
 277
 278         write_lock_bh(&dn_hash_lock);
 279         sk_del_node_init(sk);
 280         DN_SK(sk)->addrloc = 0;
 281         list = listen_hash(&DN_SK(sk)->addr);
 282         sk_add_node(sk, list);
 283         write_unlock_bh(&dn_hash_lock);
 284 }
 285
 286 int dn_sockaddr2username(struct sockaddr_dn *sdn, unsigned char *buf, unsigned char type)
 287 {
 288         int len = 2;
 289
 290         *buf++ = type;
 291
 292         switch (type) {
 293         case 0:
 294                 *buf++ = sdn->sdn_objnum;
 295                 break;
 296         case 1:
 297                 *buf++ = 0;
 298                 *buf++ = le16_to_cpu(sdn->sdn_objnamel);
 299                 memcpy(buf, sdn->sdn_objname, le16_to_cpu(sdn->sdn_objnamel));
 300                 len = 3 + le16_to_cpu(sdn->sdn_objnamel);
 301                 break;
 302         case 2:
 303                 memset(buf, 0, 5);
 304                 buf += 5;
 305                 *buf++ = le16_to_cpu(sdn->sdn_objnamel);
 306                 memcpy(buf, sdn->sdn_objname, le16_to_cpu(sdn->sdn_objnamel));
 307                 len = 7 + le16_to_cpu(sdn->sdn_objnamel);
 308                 break;
 309         }
 310
 311         return len;
 312 }
 313
 314 /*
 315  * On reception of usernames, we handle types 1 and 0 for destination
 316  * addresses only. Types 2 and 4 are used for source addresses, but the
 317  * UIC, GIC are ignored and they are both treated the same way. Type 3
 318  * is never used as I've no idea what its purpose might be or what its
 319  * format is.
 320  */
 321 int dn_username2sockaddr(unsigned char *data, int len, struct sockaddr_dn *sdn, unsigned char *fmt)
 322 {
 323         unsigned char type;
 324         int size = len;
 325         int namel = 12;
 326
 327         sdn->sdn_objnum = 0;
 328         sdn->sdn_objnamel = cpu_to_le16(0);
 329         memset(sdn->sdn_objname, 0, DN_MAXOBJL);
 330
 331         if (len < 2)
 332                 return -1;
 333
 334         len -= 2;
 335         *fmt = *data++;
 336         type = *data++;
 337
 338         switch (*fmt) {
 339         case 0:
 340                 sdn->sdn_objnum = type;
 341                 return 2;
 342         case 1:
 343                 namel = 16;
 344                 break;
 345         case 2:
 346                 len  -= 4;
 347                 data += 4;
 348                 break;
 349         case 4:
 350                 len  -= 8;
 351                 data += 8;
 352                 break;
 353         default:
 354                 return -1;
 355         }
 356
 357         len -= 1;
 358
 359         if (len < 0)
 360                 return -1;
 361
 362         sdn->sdn_objnamel = cpu_to_le16(*data++);
 363         len -= le16_to_cpu(sdn->sdn_objnamel);
 364
 365         if ((len < 0) || (le16_to_cpu(sdn->sdn_objnamel) > namel))
 366                 return -1;
 367
 368         memcpy(sdn->sdn_objname, data, le16_to_cpu(sdn->sdn_objnamel));
 369
 370         return size - len;
 371 }
 372
 373 struct sock *dn_sklist_find_listener(struct sockaddr_dn *addr)
 374 {
 375         struct hlist_head *list = listen_hash(addr);
 376         struct sock *sk;
 377
 378         read_lock(&dn_hash_lock);
 379         sk_for_each(sk, list) {
 380                 struct dn_scp *scp = DN_SK(sk);
 381                 if (sk->sk_state != TCP_LISTEN)
 382                         continue;
 383                 if (scp->addr.sdn_objnum) {
 384                         if (scp->addr.sdn_objnum != addr->sdn_objnum)
 385                                 continue;
 386                 } else {
 387                         if (addr->sdn_objnum)
 388                                 continue;
 389                         if (scp->addr.sdn_objnamel != addr->sdn_objnamel)
 390                                 continue;
 391                         if (memcmp(scp->addr.sdn_objname, addr->sdn_objname, le16_to_cpu(addr->sdn_objnamel)) != 0)
 392                                 continue;
 393                 }
 394                 sock_hold(sk);
 395                 read_unlock(&dn_hash_lock);
 396                 return sk;
 397         }
 398
 399         sk = sk_head(&dn_wild_sk);
 400         if (sk) {
 401                 if (sk->sk_state == TCP_LISTEN)
 402                         sock_hold(sk);
 403                 else
 404                         sk = NULL;
 405         }
 406
 407         read_unlock(&dn_hash_lock);
 408         return sk;
 409 }
 410
 411 struct sock *dn_find_by_skb(struct sk_buff *skb)
 412 {
 413         struct dn_skb_cb *cb = DN_SKB_CB(skb);
 414         struct sock *sk;
 415         struct dn_scp *scp;
 416
 417         read_lock(&dn_hash_lock);
 418         sk_for_each(sk, &dn_sk_hash[le16_to_cpu(cb->dst_port) & DN_SK_HASH_MASK]) {
 419                 scp = DN_SK(sk);
 420                 if (cb->src != dn_saddr2dn(&scp->peer))
 421                         continue;
 422                 if (cb->dst_port != scp->addrloc)
 423                         continue;
 424                 if (scp->addrrem && (cb->src_port != scp->addrrem))
 425                         continue;
 426                 sock_hold(sk);
 427                 goto found;
 428         }
 429         sk = NULL;
 430 found:
 431         read_unlock(&dn_hash_lock);
 432         return sk;
 433 }
 434
 435
 436
 437 static void dn_destruct(struct sock *sk)
 438 {
 439         struct dn_scp *scp = DN_SK(sk);
 440
 441         skb_queue_purge(&scp->data_xmit_queue);
 442         skb_queue_purge(&scp->other_xmit_queue);
 443         skb_queue_purge(&scp->other_receive_queue);
 444
 445         dst_release(rcu_dereference_check(sk->sk_dst_cache, 1));
 446 }
 447
 448 static int dn_memory_pressure;
 449
 450 static void dn_enter_memory_pressure(struct sock *sk)
 451 {
 452         if (!dn_memory_pressure) {
 453                 dn_memory_pressure = 1;
 454         }
 455 }
 456
 457 static struct proto dn_proto = {
 458         .name                   = "NSP",
 459         .owner                  = THIS_MODULE,
 460         .enter_memory_pressure  = dn_enter_memory_pressure,
 461         .memory_pressure        = &dn_memory_pressure,
 462         .memory_allocated       = &decnet_memory_allocated,
 463         .sysctl_mem             = sysctl_decnet_mem,
 464         .sysctl_wmem            = sysctl_decnet_wmem,
 465         .sysctl_rmem            = sysctl_decnet_rmem,
 466         .max_header             = DN_MAX_NSP_DATA_HEADER + 64,
 467         .obj_size               = sizeof(struct dn_sock),
 468 };
 469
 470 static struct sock *dn_alloc_sock(struct net *net, struct socket *sock, gfp_t gfp)
 471 {
 472         struct dn_scp *scp;
 473         struct sock *sk = sk_alloc(net, PF_DECnet, gfp, &dn_proto);
 474
 475         if  (!sk)
 476                 goto out;
 477
 478         if (sock)
 479                 sock->ops = &dn_proto_ops;
 480         sock_init_data(sock, sk);
 481
 482         sk->sk_backlog_rcv = dn_nsp_backlog_rcv;
 483         sk->sk_destruct    = dn_destruct;
 484         sk->sk_no_check    = 1;
 485         sk->sk_family      = PF_DECnet;
 486         sk->sk_protocol    = 0;
 487         sk->sk_allocation  = gfp;
 488         sk->sk_sndbuf      = sysctl_decnet_wmem[1];
 489         sk->sk_rcvbuf      = sysctl_decnet_rmem[1];
 490
 491         /* Initialization of DECnet Session Control Port                */
 492         scp = DN_SK(sk);
 493         scp->state      = DN_O;         /* Open                 */
 494         scp->numdat     = 1;            /* Next data seg to tx  */
 495         scp->numoth     = 1;            /* Next oth data to tx  */
 496         scp->ackxmt_dat = 0;            /* Last data seg ack'ed */
 497         scp->ackxmt_oth = 0;            /* Last oth data ack'ed */
 498         scp->ackrcv_dat = 0;            /* Highest data ack recv*/
 499         scp->ackrcv_oth = 0;            /* Last oth data ack rec*/
 500         scp->flowrem_sw = DN_SEND;
 501         scp->flowloc_sw = DN_SEND;
 502         scp->flowrem_dat = 0;
 503         scp->flowrem_oth = 1;
 504         scp->flowloc_dat = 0;
 505         scp->flowloc_oth = 1;
 506         scp->services_rem = 0;
 507         scp->services_loc = 1 | NSP_FC_NONE;
 508         scp->info_rem = 0;
 509         scp->info_loc = 0x03; /* NSP version 4.1 */
 510         scp->segsize_rem = 230 - DN_MAX_NSP_DATA_HEADER; /* Default: Updated by remote segsize */
 511         scp->nonagle = 0;
 512         scp->multi_ireq = 1;
 513         scp->accept_mode = ACC_IMMED;
 514         scp->addr.sdn_family    = AF_DECnet;
 515         scp->peer.sdn_family    = AF_DECnet;
 516         scp->accessdata.acc_accl = 5;
 517         memcpy(scp->accessdata.acc_acc, "LINUX", 5);
 518
 519         scp->max_window   = NSP_MAX_WINDOW;
 520         scp->snd_window   = NSP_MIN_WINDOW;
 521         scp->nsp_srtt     = NSP_INITIAL_SRTT;
 522         scp->nsp_rttvar   = NSP_INITIAL_RTTVAR;
 523         scp->nsp_rxtshift = 0;
 524
 525         skb_queue_head_init(&scp->data_xmit_queue);
 526         skb_queue_head_init(&scp->other_xmit_queue);
 527         skb_queue_head_init(&scp->other_receive_queue);
 528
 529         scp->persist = 0;
 530         scp->persist_fxn = NULL;
 531         scp->keepalive = 10 * HZ;
 532         scp->keepalive_fxn = dn_keepalive;
 533
 534         init_timer(&scp->delack_timer);
 535         scp->delack_pending = 0;
 536         scp->delack_fxn = dn_nsp_delayed_ack;
 537
 538         dn_start_slow_timer(sk);
 539 out:
 540         return sk;
 541 }
 542
 543 /*
 544  * Keepalive timer.
 545  * FIXME: Should respond to SO_KEEPALIVE etc.
 546  */
 547 static void dn_keepalive(struct sock *sk)
 548 {
 549         struct dn_scp *scp = DN_SK(sk);
 550
 551         /*
 552          * By checking the other_data transmit queue is empty
 553          * we are double checking that we are not sending too
 554          * many of these keepalive frames.
 555          */
 556         if (skb_queue_empty(&scp->other_xmit_queue))
 557                 dn_nsp_send_link(sk, DN_NOCHANGE, 0);
 558 }
 559
 560
 561 /*
 562  * Timer for shutdown/destroyed sockets.
 563  * When socket is dead & no packets have been sent for a
 564  * certain amount of time, they are removed by this
 565  * routine. Also takes care of sending out DI & DC
 566  * frames at correct times.
 567  */
 568 int dn_destroy_timer(struct sock *sk)
 569 {
 570         struct dn_scp *scp = DN_SK(sk);
 571
 572         scp->persist = dn_nsp_persist(sk);
 573
 574         switch (scp->state) {
 575         case DN_DI:
 576                 dn_nsp_send_disc(sk, NSP_DISCINIT, 0, GFP_ATOMIC);
 577                 if (scp->nsp_rxtshift >= decnet_di_count)
 578                         scp->state = DN_CN;
 579                 return 0;
 580
 581         case DN_DR:
 582                 dn_nsp_send_disc(sk, NSP_DISCINIT, 0, GFP_ATOMIC);
 583                 if (scp->nsp_rxtshift >= decnet_dr_count)
 584                         scp->state = DN_DRC;
 585                 return 0;
 586
 587         case DN_DN:
 588                 if (scp->nsp_rxtshift < decnet_dn_count) {
 589                         /* printk(KERN_DEBUG "dn_destroy_timer: DN\n"); */
 590                         dn_nsp_send_disc(sk, NSP_DISCCONF, NSP_REASON_DC,
 591                                          GFP_ATOMIC);
 592                         return 0;
 593                 }
 594         }
 595
 596         scp->persist = (HZ * decnet_time_wait);
 597
 598         if (sk->sk_socket)
 599                 return 0;
 600
 601         if ((jiffies - scp->stamp) >= (HZ * decnet_time_wait)) {
 602                 dn_unhash_sock(sk);
 603                 sock_put(sk);
 604                 return 1;
 605         }
 606
 607         return 0;
 608 }
 609
 610 static void dn_destroy_sock(struct sock *sk)
 611 {
 612         struct dn_scp *scp = DN_SK(sk);
 613
 614         scp->nsp_rxtshift = 0; /* reset back off */
 615
 616         if (sk->sk_socket) {
 617                 if (sk->sk_socket->state != SS_UNCONNECTED)
 618                         sk->sk_socket->state = SS_DISCONNECTING;
 619         }
 620
 621         sk->sk_state = TCP_CLOSE;
 622
 623         switch (scp->state) {
 624         case DN_DN:
 625                 dn_nsp_send_disc(sk, NSP_DISCCONF, NSP_REASON_DC,
 626                                  sk->sk_allocation);
 627                 scp->persist_fxn = dn_destroy_timer;
 628                 scp->persist = dn_nsp_persist(sk);
 629                 break;
 630         case DN_CR:
 631                 scp->state = DN_DR;
 632                 goto disc_reject;
 633         case DN_RUN:
 634                 scp->state = DN_DI;
 635         case DN_DI:
 636         case DN_DR:
 637 disc_reject:
 638                 dn_nsp_send_disc(sk, NSP_DISCINIT, 0, sk->sk_allocation);
 639         case DN_NC:
 640         case DN_NR:
 641         case DN_RJ:
 642         case DN_DIC:
 643         case DN_CN:
 644         case DN_DRC:
 645         case DN_CI:
 646         case DN_CD:
 647                 scp->persist_fxn = dn_destroy_timer;
 648                 scp->persist = dn_nsp_persist(sk);
 649                 break;
 650         default:
 651                 printk(KERN_DEBUG "DECnet: dn_destroy_sock passed socket in invalid state\n");
 652         case DN_O:
 653                 dn_stop_slow_timer(sk);
 654
 655                 dn_unhash_sock_bh(sk);
 656                 sock_put(sk);
 657
 658                 break;
 659         }
 660 }
 661
 662 char *dn_addr2asc(__u16 addr, char *buf)
 663 {
 664         unsigned short node, area;
 665
 666         node = addr & 0x03ff;
 667         area = addr >> 10;
 668         sprintf(buf, "%hd.%hd", area, node);
 669
 670         return buf;
 671 }
 672
 673
 674
 675 static int dn_create(struct net *net, struct socket *sock, int protocol,
 676                      int kern)
 677 {
 678         struct sock *sk;
 679
 680         if (!net_eq(net, &init_net))
 681                 return -EAFNOSUPPORT;
 682
 683         switch (sock->type) {
 684         case SOCK_SEQPACKET:
 685                 if (protocol != DNPROTO_NSP)
 686                         return -EPROTONOSUPPORT;
 687                 break;
 688         case SOCK_STREAM:
 689                 break;
 690         default:
 691                 return -ESOCKTNOSUPPORT;
 692         }
 693
 694
 695         if ((sk = dn_alloc_sock(net, sock, GFP_KERNEL)) == NULL)
 696                 return -ENOBUFS;
 697
 698         sk->sk_protocol = protocol;
 699
 700         return 0;
 701 }
 702
 703
 704 static int
 705 dn_release(struct socket *sock)
 706 {
 707         struct sock *sk = sock->sk;
 708
 709         if (sk) {
 710                 sock_orphan(sk);
 711                 sock_hold(sk);
 712                 lock_sock(sk);
 713                 dn_destroy_sock(sk);
 714                 release_sock(sk);
 715                 sock_put(sk);
 716         }
 717
 718         return 0;
 719 }
 720
 721 static int dn_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 722 {
 723         struct sock *sk = sock->sk;
 724         struct dn_scp *scp = DN_SK(sk);
 725         struct sockaddr_dn *saddr = (struct sockaddr_dn *)uaddr;
 726         struct net_device *dev, *ldev;
 727         int rv;
 728
 729         if (addr_len != sizeof(struct sockaddr_dn))
 730                 return -EINVAL;
 731
 732         if (saddr->sdn_family != AF_DECnet)
 733                 return -EINVAL;
 734
 735         if (le16_to_cpu(saddr->sdn_nodeaddrl) && (le16_to_cpu(saddr->sdn_nodeaddrl) != 2))
 736                 return -EINVAL;
 737
 738         if (le16_to_cpu(saddr->sdn_objnamel) > DN_MAXOBJL)
 739                 return -EINVAL;
 740
 741         if (saddr->sdn_flags & ~SDF_WILD)
 742                 return -EINVAL;
 743
 744         if (!capable(CAP_NET_BIND_SERVICE) && (saddr->sdn_objnum ||
 745             (saddr->sdn_flags & SDF_WILD)))
 746                 return -EACCES;
 747
 748         if (!(saddr->sdn_flags & SDF_WILD)) {
 749                 if (le16_to_cpu(saddr->sdn_nodeaddrl)) {
 750                         rcu_read_lock();
 751                         ldev = NULL;
 752                         for_each_netdev_rcu(&init_net, dev) {
 753                                 if (!dev->dn_ptr)
 754                                         continue;
 755                                 if (dn_dev_islocal(dev, dn_saddr2dn(saddr))) {
 756                                         ldev = dev;
 757                                         break;
 758                                 }
 759                         }
 760                         rcu_read_unlock();
 761                         if (ldev == NULL)
 762                                 return -EADDRNOTAVAIL;
 763                 }
 764         }
 765
 766         rv = -EINVAL;
 767         lock_sock(sk);
 768         if (sock_flag(sk, SOCK_ZAPPED)) {
 769                 memcpy(&scp->addr, saddr, addr_len);
 770                 sock_reset_flag(sk, SOCK_ZAPPED);
 771
 772                 rv = dn_hash_sock(sk);
 773                 if (rv)
 774                         sock_set_flag(sk, SOCK_ZAPPED);
 775         }
 776         release_sock(sk);
 777
 778         return rv;
 779 }
 780
 781
 782 static int dn_auto_bind(struct socket *sock)
 783 {
 784         struct sock *sk = sock->sk;
 785         struct dn_scp *scp = DN_SK(sk);
 786         int rv;
 787
 788         sock_reset_flag(sk, SOCK_ZAPPED);
 789
 790         scp->addr.sdn_flags  = 0;
 791         scp->addr.sdn_objnum = 0;
 792
 793         /*
 794          * This stuff is to keep compatibility with Eduardo's
 795          * patch. I hope I can dispense with it shortly...
 796          */
 797         if ((scp->accessdata.acc_accl != 0) &&
 798                 (scp->accessdata.acc_accl <= 12)) {
 799
 800                 scp->addr.sdn_objnamel = cpu_to_le16(scp->accessdata.acc_accl);
 801                 memcpy(scp->addr.sdn_objname, scp->accessdata.acc_acc, le16_to_cpu(scp->addr.sdn_objnamel));
 802
 803                 scp->accessdata.acc_accl = 0;
 804                 memset(scp->accessdata.acc_acc, 0, 40);
 805         }
 806         /* End of compatibility stuff */
 807
 808         scp->addr.sdn_add.a_len = cpu_to_le16(2);
 809         rv = dn_dev_bind_default((__le16 *)scp->addr.sdn_add.a_addr);
 810         if (rv == 0) {
 811                 rv = dn_hash_sock(sk);
 812                 if (rv)
 813                         sock_set_flag(sk, SOCK_ZAPPED);
 814         }
 815
 816         return rv;
 817 }
 818
 819 static int dn_confirm_accept(struct sock *sk, long *timeo, gfp_t allocation)
 820 {
 821         struct dn_scp *scp = DN_SK(sk);
 822         DEFINE_WAIT(wait);
 823         int err;
 824
 825         if (scp->state != DN_CR)
 826                 return -EINVAL;
 827
 828         scp->state = DN_CC;
 829         scp->segsize_loc = dst_metric_advmss(__sk_dst_get(sk));
 830         dn_send_conn_conf(sk, allocation);
 831
 832         prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
 833         for(;;) {
 834                 release_sock(sk);
 835                 if (scp->state == DN_CC)
 836                         *timeo = schedule_timeout(*timeo);
 837                 lock_sock(sk);
 838                 err = 0;
 839                 if (scp->state == DN_RUN)
 840                         break;
 841                 err = sock_error(sk);
 842                 if (err)
 843                         break;
 844                 err = sock_intr_errno(*timeo);
 845                 if (signal_pending(current))
 846                         break;
 847                 err = -EAGAIN;
 848                 if (!*timeo)
 849                         break;
 850                 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
 851         }
 852         finish_wait(sk_sleep(sk), &wait);
 853         if (err == 0) {
 854                 sk->sk_socket->state = SS_CONNECTED;
 855         } else if (scp->state != DN_CC) {
 856                 sk->sk_socket->state = SS_UNCONNECTED;
 857         }
 858         return err;
 859 }
 860
 861 static int dn_wait_run(struct sock *sk, long *timeo)
 862 {
 863         struct dn_scp *scp = DN_SK(sk);
 864         DEFINE_WAIT(wait);
 865         int err = 0;
 866
 867         if (scp->state == DN_RUN)
 868                 goto out;
 869
 870         if (!*timeo)
 871                 return -EALREADY;
 872
 873         prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
 874         for(;;) {
 875                 release_sock(sk);
 876                 if (scp->state == DN_CI || scp->state == DN_CC)
 877                         *timeo = schedule_timeout(*timeo);
 878                 lock_sock(sk);
 879                 err = 0;
 880                 if (scp->state == DN_RUN)
 881                         break;
 882                 err = sock_error(sk);
 883                 if (err)
 884                         break;
 885                 err = sock_intr_errno(*timeo);
 886                 if (signal_pending(current))
 887                         break;
 888                 err = -ETIMEDOUT;
 889                 if (!*timeo)
 890                         break;
 891                 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
 892         }
 893         finish_wait(sk_sleep(sk), &wait);
 894 out:
 895         if (err == 0) {
 896                 sk->sk_socket->state = SS_CONNECTED;
 897         } else if (scp->state != DN_CI && scp->state != DN_CC) {
 898                 sk->sk_socket->state = SS_UNCONNECTED;
 899         }
 900         return err;
 901 }
 902
 903 static int __dn_connect(struct sock *sk, struct sockaddr_dn *addr, int addrlen, long *timeo, int flags)
 904 {
 905         struct socket *sock = sk->sk_socket;
 906         struct dn_scp *scp = DN_SK(sk);
 907         int err = -EISCONN;
 908         struct flowidn fld;
 909         struct dst_entry *dst;
 910
 911         if (sock->state == SS_CONNECTED)
 912                 goto out;
 913
 914         if (sock->state == SS_CONNECTING) {
 915                 err = 0;
 916                 if (scp->state == DN_RUN) {
 917                         sock->state = SS_CONNECTED;
 918                         goto out;
 919                 }
 920                 err = -ECONNREFUSED;
 921                 if (scp->state != DN_CI && scp->state != DN_CC) {
 922                         sock->state = SS_UNCONNECTED;
 923                         goto out;
 924                 }
 925                 return dn_wait_run(sk, timeo);
 926         }
 927
 928         err = -EINVAL;
 929         if (scp->state != DN_O)
 930                 goto out;
 931
 932         if (addr == NULL || addrlen != sizeof(struct sockaddr_dn))
 933                 goto out;
 934         if (addr->sdn_family != AF_DECnet)
 935                 goto out;
 936         if (addr->sdn_flags & SDF_WILD)
 937                 goto out;
 938
 939         if (sock_flag(sk, SOCK_ZAPPED)) {
 940                 err = dn_auto_bind(sk->sk_socket);
 941                 if (err)
 942                         goto out;
 943         }
 944
 945         memcpy(&scp->peer, addr, sizeof(struct sockaddr_dn));
 946
 947         err = -EHOSTUNREACH;
 948         memset(&fld, 0, sizeof(fld));
 949         fld.flowidn_oif = sk->sk_bound_dev_if;
 950         fld.daddr = dn_saddr2dn(&scp->peer);
 951         fld.saddr = dn_saddr2dn(&scp->addr);
 952         dn_sk_ports_copy(&fld, scp);
 953         fld.flowidn_proto = DNPROTO_NSP;
 954         if (dn_route_output_sock(&sk->sk_dst_cache, &fld, sk, flags) < 0)
 955                 goto out;
 956         dst = __sk_dst_get(sk);
 957         sk->sk_route_caps = dst->dev->features;
 958         sock->state = SS_CONNECTING;
 959         scp->state = DN_CI;
 960         scp->segsize_loc = dst_metric_advmss(dst);
 961
 962         dn_nsp_send_conninit(sk, NSP_CI);
 963         err = -EINPROGRESS;
 964         if (*timeo) {
 965                 err = dn_wait_run(sk, timeo);
 966         }
 967 out:
 968         return err;
 969 }
 970
 971 static int dn_connect(struct socket *sock, struct sockaddr *uaddr, int addrlen, int flags)
 972 {
 973         struct sockaddr_dn *addr = (struct sockaddr_dn *)uaddr;
 974         struct sock *sk = sock->sk;
 975         int err;
 976         long timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
 977
 978         lock_sock(sk);
 979         err = __dn_connect(sk, addr, addrlen, &timeo, 0);
 980         release_sock(sk);
 981
 982         return err;
 983 }
 984
 985 static inline int dn_check_state(struct sock *sk, struct sockaddr_dn *addr, int addrlen, long *timeo, int flags)
 986 {
 987         struct dn_scp *scp = DN_SK(sk);
 988
 989         switch (scp->state) {
 990         case DN_RUN:
 991                 return 0;
 992         case DN_CR:
 993                 return dn_confirm_accept(sk, timeo, sk->sk_allocation);
 994         case DN_CI:
 995         case DN_CC:
 996                 return dn_wait_run(sk, timeo);
 997         case DN_O:
 998                 return __dn_connect(sk, addr, addrlen, timeo, flags);
 999         }
1000
1001         return -EINVAL;
1002 }
1003
1004
1005 static void dn_access_copy(struct sk_buff *skb, struct accessdata_dn *acc)
1006 {
1007         unsigned char *ptr = skb->data;
1008
1009         acc->acc_userl = *ptr++;
1010         memcpy(&acc->acc_user, ptr, acc->acc_userl);
1011         ptr += acc->acc_userl;
1012
1013         acc->acc_passl = *ptr++;
1014         memcpy(&acc->acc_pass, ptr, acc->acc_passl);
1015         ptr += acc->acc_passl;
1016
1017         acc->acc_accl = *ptr++;
1018         memcpy(&acc->acc_acc, ptr, acc->acc_accl);
1019
1020         skb_pull(skb, acc->acc_accl + acc->acc_passl + acc->acc_userl + 3);
1021
1022 }
1023
1024 static void dn_user_copy(struct sk_buff *skb, struct optdata_dn *opt)
1025 {
1026         unsigned char *ptr = skb->data;
1027         u16 len = *ptr++; /* yes, it's 8bit on the wire */
1028
1029         BUG_ON(len > 16); /* we've checked the contents earlier */
1030         opt->opt_optl   = cpu_to_le16(len);
1031         opt->opt_status = 0;
1032         memcpy(opt->opt_data, ptr, len);
1033         skb_pull(skb, len + 1);
1034 }
1035
1036 static struct sk_buff *dn_wait_for_connect(struct sock *sk, long *timeo)
1037 {
1038         DEFINE_WAIT(wait);
1039         struct sk_buff *skb = NULL;
1040         int err = 0;
1041
1042         prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1043         for(;;) {
1044                 release_sock(sk);
1045                 skb = skb_dequeue(&sk->sk_receive_queue);
1046                 if (skb == NULL) {
1047                         *timeo = schedule_timeout(*timeo);
1048                         skb = skb_dequeue(&sk->sk_receive_queue);
1049                 }
1050                 lock_sock(sk);
1051                 if (skb != NULL)
1052                         break;
1053                 err = -EINVAL;
1054                 if (sk->sk_state != TCP_LISTEN)
1055                         break;
1056                 err = sock_intr_errno(*timeo);
1057                 if (signal_pending(current))
1058                         break;
1059                 err = -EAGAIN;
1060                 if (!*timeo)
1061                         break;
1062                 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1063         }
1064         finish_wait(sk_sleep(sk), &wait);
1065
1066         return skb == NULL ? ERR_PTR(err) : skb;
1067 }
1068
1069 static int dn_accept(struct socket *sock, struct socket *newsock, int flags)
1070 {
1071         struct sock *sk = sock->sk, *newsk;
1072         struct sk_buff *skb = NULL;
1073         struct dn_skb_cb *cb;
1074         unsigned char menuver;
1075         int err = 0;
1076         unsigned char type;
1077         long timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
1078         struct dst_entry *dst;
1079
1080         lock_sock(sk);
1081
1082         if (sk->sk_state != TCP_LISTEN || DN_SK(sk)->state != DN_O) {
1083                 release_sock(sk);
1084                 return -EINVAL;
1085         }
1086
1087         skb = skb_dequeue(&sk->sk_receive_queue);
1088         if (skb == NULL) {
1089                 skb = dn_wait_for_connect(sk, &timeo);
1090                 if (IS_ERR(skb)) {
1091                         release_sock(sk);
1092                         return PTR_ERR(skb);
1093                 }
1094         }
1095
1096         cb = DN_SKB_CB(skb);
1097         sk->sk_ack_backlog--;
1098         newsk = dn_alloc_sock(sock_net(sk), newsock, sk->sk_allocation);
1099         if (newsk == NULL) {
1100                 release_sock(sk);
1101                 kfree_skb(skb);
1102                 return -ENOBUFS;
1103         }
1104         release_sock(sk);
1105
1106         dst = skb_dst(skb);
1107         sk_dst_set(newsk, dst);
1108         skb_dst_set(skb, NULL);
1109
1110         DN_SK(newsk)->state        = DN_CR;
1111         DN_SK(newsk)->addrrem      = cb->src_port;
1112         DN_SK(newsk)->services_rem = cb->services;
1113         DN_SK(newsk)->info_rem     = cb->info;
1114         DN_SK(newsk)->segsize_rem  = cb->segsize;
1115         DN_SK(newsk)->accept_mode  = DN_SK(sk)->accept_mode;
1116
1117         if (DN_SK(newsk)->segsize_rem < 230)
1118                 DN_SK(newsk)->segsize_rem = 230;
1119
1120         if ((DN_SK(newsk)->services_rem & NSP_FC_MASK) == NSP_FC_NONE)
1121                 DN_SK(newsk)->max_window = decnet_no_fc_max_cwnd;
1122
1123         newsk->sk_state  = TCP_LISTEN;
1124         memcpy(&(DN_SK(newsk)->addr), &(DN_SK(sk)->addr), sizeof(struct sockaddr_dn));
1125
1126         /*
1127          * If we are listening on a wild socket, we don't want
1128          * the newly created socket on the wrong hash queue.
1129          */
1130         DN_SK(newsk)->addr.sdn_flags &= ~SDF_WILD;
1131
1132         skb_pull(skb, dn_username2sockaddr(skb->data, skb->len, &(DN_SK(newsk)->addr), &type));
1133         skb_pull(skb, dn_username2sockaddr(skb->data, skb->len, &(DN_SK(newsk)->peer), &type));
1134         *(__le16 *)(DN_SK(newsk)->peer.sdn_add.a_addr) = cb->src;
1135         *(__le16 *)(DN_SK(newsk)->addr.sdn_add.a_addr) = cb->dst;
1136
1137         menuver = *skb->data;
1138         skb_pull(skb, 1);
1139
1140         if (menuver & DN_MENUVER_ACC)
1141                 dn_access_copy(skb, &(DN_SK(newsk)->accessdata));
1142
1143         if (menuver & DN_MENUVER_USR)
1144                 dn_user_copy(skb, &(DN_SK(newsk)->conndata_in));
1145
1146         if (menuver & DN_MENUVER_PRX)
1147                 DN_SK(newsk)->peer.sdn_flags |= SDF_PROXY;
1148
1149         if (menuver & DN_MENUVER_UIC)
1150                 DN_SK(newsk)->peer.sdn_flags |= SDF_UICPROXY;
1151
1152         kfree_skb(skb);
1153
1154         memcpy(&(DN_SK(newsk)->conndata_out), &(DN_SK(sk)->conndata_out),
1155                 sizeof(struct optdata_dn));
1156         memcpy(&(DN_SK(newsk)->discdata_out), &(DN_SK(sk)->discdata_out),
1157                 sizeof(struct optdata_dn));
1158
1159         lock_sock(newsk);
1160         err = dn_hash_sock(newsk);
1161         if (err == 0) {
1162                 sock_reset_flag(newsk, SOCK_ZAPPED);
1163                 dn_send_conn_ack(newsk);
1164
1165                 /*
1166                  * Here we use sk->sk_allocation since although the conn conf is
1167                  * for the newsk, the context is the old socket.
1168                  */
1169                 if (DN_SK(newsk)->accept_mode == ACC_IMMED)
1170                         err = dn_confirm_accept(newsk, &timeo,
1171                                                 sk->sk_allocation);
1172         }
1173         release_sock(newsk);
1174         return err;
1175 }
1176
1177
1178 static int dn_getname(struct socket *sock, struct sockaddr *uaddr,int *uaddr_len,int peer)
1179 {
1180         struct sockaddr_dn *sa = (struct sockaddr_dn *)uaddr;
1181         struct sock *sk = sock->sk;
1182         struct dn_scp *scp = DN_SK(sk);
1183
1184         *uaddr_len = sizeof(struct sockaddr_dn);
1185
1186         lock_sock(sk);
1187
1188         if (peer) {
1189                 if ((sock->state != SS_CONNECTED &&
1190                      sock->state != SS_CONNECTING) &&
1191                     scp->accept_mode == ACC_IMMED) {
1192                         release_sock(sk);
1193                         return -ENOTCONN;
1194                 }
1195
1196                 memcpy(sa, &scp->peer, sizeof(struct sockaddr_dn));
1197         } else {
1198                 memcpy(sa, &scp->addr, sizeof(struct sockaddr_dn));
1199         }
1200
1201         release_sock(sk);
1202
1203         return 0;
1204 }
1205
1206
1207 static unsigned int dn_poll(struct file *file, struct socket *sock, poll_table  *wait)
1208 {
1209         struct sock *sk = sock->sk;
1210         struct dn_scp *scp = DN_SK(sk);
1211         int mask = datagram_poll(file, sock, wait);
1212
1213         if (!skb_queue_empty(&scp->other_receive_queue))
1214                 mask |= POLLRDBAND;
1215
1216         return mask;
1217 }
1218
1219 static int dn_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1220 {
1221         struct sock *sk = sock->sk;
1222         struct dn_scp *scp = DN_SK(sk);
1223         int err = -EOPNOTSUPP;
1224         long amount = 0;
1225         struct sk_buff *skb;
1226         int val;
1227
1228         switch(cmd)
1229         {
1230         case SIOCGIFADDR:
1231         case SIOCSIFADDR:
1232                 return dn_dev_ioctl(cmd, (void __user *)arg);
1233
1234         case SIOCATMARK:
1235                 lock_sock(sk);
1236                 val = !skb_queue_empty(&scp->other_receive_queue);
1237                 if (scp->state != DN_RUN)
1238                         val = -ENOTCONN;
1239                 release_sock(sk);
1240                 return val;
1241
1242         case TIOCOUTQ:
1243                 amount = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
1244                 if (amount < 0)
1245                         amount = 0;
1246                 err = put_user(amount, (int __user *)arg);
1247                 break;
1248
1249         case TIOCINQ:
1250                 lock_sock(sk);
1251                 skb = skb_peek(&scp->other_receive_queue);
1252                 if (skb) {
1253                         amount = skb->len;
1254                 } else {
1255                         skb_queue_walk(&sk->sk_receive_queue, skb)
1256                                 amount += skb->len;
1257                 }
1258                 release_sock(sk);
1259                 err = put_user(amount, (int __user *)arg);
1260                 break;
1261
1262         default:
1263                 err = -ENOIOCTLCMD;
1264                 break;
1265         }
1266
1267         return err;
1268 }
1269
1270 static int dn_listen(struct socket *sock, int backlog)
1271 {
1272         struct sock *sk = sock->sk;
1273         int err = -EINVAL;
1274
1275         lock_sock(sk);
1276
1277         if (sock_flag(sk, SOCK_ZAPPED))
1278                 goto out;
1279
1280         if ((DN_SK(sk)->state != DN_O) || (sk->sk_state == TCP_LISTEN))
1281                 goto out;
1282
1283         sk->sk_max_ack_backlog = backlog;
1284         sk->sk_ack_backlog     = 0;
1285         sk->sk_state           = TCP_LISTEN;
1286         err                 = 0;
1287         dn_rehash_sock(sk);
1288
1289 out:
1290         release_sock(sk);
1291
1292         return err;
1293 }
1294
1295
1296 static int dn_shutdown(struct socket *sock, int how)
1297 {
1298         struct sock *sk = sock->sk;
1299         struct dn_scp *scp = DN_SK(sk);
1300         int err = -ENOTCONN;
1301
1302         lock_sock(sk);
1303
1304         if (sock->state == SS_UNCONNECTED)
1305                 goto out;
1306
1307         err = 0;
1308         if (sock->state == SS_DISCONNECTING)
1309                 goto out;
1310
1311         err = -EINVAL;
1312         if (scp->state == DN_O)
1313                 goto out;
1314
1315         if (how != SHUT_RDWR)
1316                 goto out;
1317
1318         sk->sk_shutdown = SHUTDOWN_MASK;
1319         dn_destroy_sock(sk);
1320         err = 0;
1321
1322 out:
1323         release_sock(sk);
1324
1325         return err;
1326 }
1327
1328 static int dn_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
1329 {
1330         struct sock *sk = sock->sk;
1331         int err;
1332
1333         lock_sock(sk);
1334         err = __dn_setsockopt(sock, level, optname, optval, optlen, 0);
1335         release_sock(sk);
1336
1337         return err;
1338 }
1339
1340 static int __dn_setsockopt(struct socket *sock, int level,int optname, char __user *optval, unsigned int optlen, int flags)
1341 {
1342         struct  sock *sk = sock->sk;
1343         struct dn_scp *scp = DN_SK(sk);
1344         long timeo;
1345         union {
1346                 struct optdata_dn opt;
1347                 struct accessdata_dn acc;
1348                 int mode;
1349                 unsigned long win;
1350                 int val;
1351                 unsigned char services;
1352                 unsigned char info;
1353         } u;
1354         int err;
1355
1356         if (optlen && !optval)
1357                 return -EINVAL;
1358
1359         if (optlen > sizeof(u))
1360                 return -EINVAL;
1361
1362         if (copy_from_user(&u, optval, optlen))
1363                 return -EFAULT;
1364
1365         switch (optname) {
1366         case DSO_CONDATA:
1367                 if (sock->state == SS_CONNECTED)
1368                         return -EISCONN;
1369                 if ((scp->state != DN_O) && (scp->state != DN_CR))
1370                         return -EINVAL;
1371
1372                 if (optlen != sizeof(struct optdata_dn))
1373                         return -EINVAL;
1374
1375                 if (le16_to_cpu(u.opt.opt_optl) > 16)
1376                         return -EINVAL;
1377
1378                 memcpy(&scp->conndata_out, &u.opt, optlen);
1379                 break;
1380
1381         case DSO_DISDATA:
1382                 if (sock->state != SS_CONNECTED &&
1383                     scp->accept_mode == ACC_IMMED)
1384                         return -ENOTCONN;
1385
1386                 if (optlen != sizeof(struct optdata_dn))
1387                         return -EINVAL;
1388
1389                 if (le16_to_cpu(u.opt.opt_optl) > 16)
1390                         return -EINVAL;
1391
1392                 memcpy(&scp->discdata_out, &u.opt, optlen);
1393                 break;
1394
1395         case DSO_CONACCESS:
1396                 if (sock->state == SS_CONNECTED)
1397                         return -EISCONN;
1398                 if (scp->state != DN_O)
1399                         return -EINVAL;
1400
1401                 if (optlen != sizeof(struct accessdata_dn))
1402                         return -EINVAL;
1403
1404                 if ((u.acc.acc_accl > DN_MAXACCL) ||
1405                     (u.acc.acc_passl > DN_MAXACCL) ||
1406                     (u.acc.acc_userl > DN_MAXACCL))
1407                         return -EINVAL;
1408
1409                 memcpy(&scp->accessdata, &u.acc, optlen);
1410                 break;
1411
1412         case DSO_ACCEPTMODE:
1413                 if (sock->state == SS_CONNECTED)
1414                         return -EISCONN;
1415                 if (scp->state != DN_O)
1416                         return -EINVAL;
1417
1418                 if (optlen != sizeof(int))
1419                         return -EINVAL;
1420
1421                 if ((u.mode != ACC_IMMED) && (u.mode != ACC_DEFER))
1422                         return -EINVAL;
1423
1424                 scp->accept_mode = (unsigned char)u.mode;
1425                 break;
1426
1427         case DSO_CONACCEPT:
1428                 if (scp->state != DN_CR)
1429                         return -EINVAL;
1430                 timeo = sock_rcvtimeo(sk, 0);
1431                 err = dn_confirm_accept(sk, &timeo, sk->sk_allocation);
1432                 return err;
1433
1434         case DSO_CONREJECT:
1435                 if (scp->state != DN_CR)
1436                         return -EINVAL;
1437
1438                 scp->state = DN_DR;
1439                 sk->sk_shutdown = SHUTDOWN_MASK;
1440                 dn_nsp_send_disc(sk, 0x38, 0, sk->sk_allocation);
1441                 break;
1442
1443         default:
1444 #ifdef CONFIG_NETFILTER
1445                 return nf_setsockopt(sk, PF_DECnet, optname, optval, optlen);
1446 #endif
1447         case DSO_LINKINFO:
1448         case DSO_STREAM:
1449         case DSO_SEQPACKET:
1450                 return -ENOPROTOOPT;
1451
1452         case DSO_MAXWINDOW:
1453                 if (optlen != sizeof(unsigned long))
1454                         return -EINVAL;
1455                 if (u.win > NSP_MAX_WINDOW)
1456                         u.win = NSP_MAX_WINDOW;
1457                 if (u.win == 0)
1458                         return -EINVAL;
1459                 scp->max_window = u.win;
1460                 if (scp->snd_window > u.win)
1461                         scp->snd_window = u.win;
1462                 break;
1463
1464         case DSO_NODELAY:
1465                 if (optlen != sizeof(int))
1466                         return -EINVAL;
1467                 if (scp->nonagle == 2)
1468                         return -EINVAL;
1469                 scp->nonagle = (u.val == 0) ? 0 : 1;
1470                 /* if (scp->nonagle == 1) { Push pending frames } */
1471                 break;
1472
1473         case DSO_CORK:
1474                 if (optlen != sizeof(int))
1475                         return -EINVAL;
1476                 if (scp->nonagle == 1)
1477                         return -EINVAL;
1478                 scp->nonagle = (u.val == 0) ? 0 : 2;
1479                 /* if (scp->nonagle == 0) { Push pending frames } */
1480                 break;
1481
1482         case DSO_SERVICES:
1483                 if (optlen != sizeof(unsigned char))
1484                         return -EINVAL;
1485                 if ((u.services & ~NSP_FC_MASK) != 0x01)
1486                         return -EINVAL;
1487                 if ((u.services & NSP_FC_MASK) == NSP_FC_MASK)
1488                         return -EINVAL;
1489                 scp->services_loc = u.services;
1490                 break;
1491
1492         case DSO_INFO:
1493                 if (optlen != sizeof(unsigned char))
1494                         return -EINVAL;
1495                 if (u.info & 0xfc)
1496                         return -EINVAL;
1497                 scp->info_loc = u.info;
1498                 break;
1499         }
1500
1501         return 0;
1502 }
1503
1504 static int dn_getsockopt(struct socket *sock, int level, int optname, char __user *optval, int __user *optlen)
1505 {
1506         struct sock *sk = sock->sk;
1507         int err;
1508
1509         lock_sock(sk);
1510         err = __dn_getsockopt(sock, level, optname, optval, optlen, 0);
1511         release_sock(sk);
1512
1513         return err;
1514 }
1515
1516 static int __dn_getsockopt(struct socket *sock, int level,int optname, char __user *optval,int __user *optlen, int flags)
1517 {
1518         struct  sock *sk = sock->sk;
1519         struct dn_scp *scp = DN_SK(sk);
1520         struct linkinfo_dn link;
1521         unsigned int r_len;
1522         void *r_data = NULL;
1523         unsigned int val;
1524
1525         if(get_user(r_len , optlen))
1526                 return -EFAULT;
1527
1528         switch (optname) {
1529         case DSO_CONDATA:
1530                 if (r_len > sizeof(struct optdata_dn))
1531                         r_len = sizeof(struct optdata_dn);
1532                 r_data = &scp->conndata_in;
1533                 break;
1534
1535         case DSO_DISDATA:
1536                 if (r_len > sizeof(struct optdata_dn))
1537                         r_len = sizeof(struct optdata_dn);
1538                 r_data = &scp->discdata_in;
1539                 break;
1540
1541         case DSO_CONACCESS:
1542                 if (r_len > sizeof(struct accessdata_dn))
1543                         r_len = sizeof(struct accessdata_dn);
1544                 r_data = &scp->accessdata;
1545                 break;
1546
1547         case DSO_ACCEPTMODE:
1548                 if (r_len > sizeof(unsigned char))
1549                         r_len = sizeof(unsigned char);
1550                 r_data = &scp->accept_mode;
1551                 break;
1552
1553         case DSO_LINKINFO:
1554                 if (r_len > sizeof(struct linkinfo_dn))
1555                         r_len = sizeof(struct linkinfo_dn);
1556
1557                 memset(&link, 0, sizeof(link));
1558
1559                 switch (sock->state) {
1560                 case SS_CONNECTING:
1561                         link.idn_linkstate = LL_CONNECTING;
1562                         break;
1563                 case SS_DISCONNECTING:
1564                         link.idn_linkstate = LL_DISCONNECTING;
1565                         break;
1566                 case SS_CONNECTED:
1567                         link.idn_linkstate = LL_RUNNING;
1568                         break;
1569                 default:
1570                         link.idn_linkstate = LL_INACTIVE;
1571                 }
1572
1573                 link.idn_segsize = scp->segsize_rem;
1574                 r_data = &link;
1575                 break;
1576
1577         default:
1578 #ifdef CONFIG_NETFILTER
1579         {
1580                 int ret, len;
1581
1582                 if (get_user(len, optlen))
1583                         return -EFAULT;
1584
1585                 ret = nf_getsockopt(sk, PF_DECnet, optname, optval, &len);
1586                 if (ret >= 0)
1587                         ret = put_user(len, optlen);
1588                 return ret;
1589         }
1590 #endif
1591         case DSO_STREAM:
1592         case DSO_SEQPACKET:
1593         case DSO_CONACCEPT:
1594         case DSO_CONREJECT:
1595                 return -ENOPROTOOPT;
1596
1597         case DSO_MAXWINDOW:
1598                 if (r_len > sizeof(unsigned long))
1599                         r_len = sizeof(unsigned long);
1600                 r_data = &scp->max_window;
1601                 break;
1602
1603         case DSO_NODELAY:
1604                 if (r_len > sizeof(int))
1605                         r_len = sizeof(int);
1606                 val = (scp->nonagle == 1);
1607                 r_data = &val;
1608                 break;
1609
1610         case DSO_CORK:
1611                 if (r_len > sizeof(int))
1612                         r_len = sizeof(int);
1613                 val = (scp->nonagle == 2);
1614                 r_data = &val;
1615                 break;
1616
1617         case DSO_SERVICES:
1618                 if (r_len > sizeof(unsigned char))
1619                         r_len = sizeof(unsigned char);
1620                 r_data = &scp->services_rem;
1621                 break;
1622
1623         case DSO_INFO:
1624                 if (r_len > sizeof(unsigned char))
1625                         r_len = sizeof(unsigned char);
1626                 r_data = &scp->info_rem;
1627                 break;
1628         }
1629
1630         if (r_data) {
1631                 if (copy_to_user(optval, r_data, r_len))
1632                         return -EFAULT;
1633                 if (put_user(r_len, optlen))
1634                         return -EFAULT;
1635         }
1636
1637         return 0;
1638 }
1639
1640
1641 static int dn_data_ready(struct sock *sk, struct sk_buff_head *q, int flags, int target)
1642 {
1643         struct sk_buff *skb;
1644         int len = 0;
1645
1646         if (flags & MSG_OOB)
1647                 return !skb_queue_empty(q) ? 1 : 0;
1648
1649         skb_queue_walk(q, skb) {
1650                 struct dn_skb_cb *cb = DN_SKB_CB(skb);
1651                 len += skb->len;
1652
1653                 if (cb->nsp_flags & 0x40) {
1654                         /* SOCK_SEQPACKET reads to EOM */
1655                         if (sk->sk_type == SOCK_SEQPACKET)
1656                                 return 1;
1657                         /* so does SOCK_STREAM unless WAITALL is specified */
1658                         if (!(flags & MSG_WAITALL))
1659                                 return 1;
1660                 }
1661
1662                 /* minimum data length for read exceeded */
1663                 if (len >= target)
1664                         return 1;
1665         }
1666
1667         return 0;
1668 }
1669
1670
1671 static int dn_recvmsg(struct kiocb *iocb, struct socket *sock,
1672         struct msghdr *msg, size_t size, int flags)
1673 {
1674         struct sock *sk = sock->sk;
1675         struct dn_scp *scp = DN_SK(sk);
1676         struct sk_buff_head *queue = &sk->sk_receive_queue;
1677         size_t target = size > 1 ? 1 : 0;
1678         size_t copied = 0;
1679         int rv = 0;
1680         struct sk_buff *skb, *n;
1681         struct dn_skb_cb *cb = NULL;
1682         unsigned char eor = 0;
1683         long timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
1684
1685         lock_sock(sk);
1686
1687         if (sock_flag(sk, SOCK_ZAPPED)) {
1688                 rv = -EADDRNOTAVAIL;
1689                 goto out;
1690         }
1691
1692         if (sk->sk_shutdown & RCV_SHUTDOWN) {
1693                 rv = 0;
1694                 goto out;
1695         }
1696
1697         rv = dn_check_state(sk, NULL, 0, &timeo, flags);
1698         if (rv)
1699                 goto out;
1700
1701         if (flags & ~(MSG_CMSG_COMPAT|MSG_PEEK|MSG_OOB|MSG_WAITALL|MSG_DONTWAIT|MSG_NOSIGNAL)) {
1702                 rv = -EOPNOTSUPP;
1703                 goto out;
1704         }
1705
1706         if (flags & MSG_OOB)
1707                 queue = &scp->other_receive_queue;
1708
1709         if (flags & MSG_WAITALL)
1710                 target = size;
1711
1712
1713         /*
1714          * See if there is data ready to read, sleep if there isn't
1715          */
1716         for(;;) {
1717                 DEFINE_WAIT(wait);
1718
1719                 if (sk->sk_err)
1720                         goto out;
1721
1722                 if (!skb_queue_empty(&scp->other_receive_queue)) {
1723                         if (!(flags & MSG_OOB)) {
1724                                 msg->msg_flags |= MSG_OOB;
1725                                 if (!scp->other_report) {
1726                                         scp->other_report = 1;
1727                                         goto out;
1728                                 }
1729                         }
1730                 }
1731
1732                 if (scp->state != DN_RUN)
1733                         goto out;
1734
1735                 if (signal_pending(current)) {
1736                         rv = sock_intr_errno(timeo);
1737                         goto out;
1738                 }
1739
1740                 if (dn_data_ready(sk, queue, flags, target))
1741                         break;
1742
1743                 if (flags & MSG_DONTWAIT) {
1744                         rv = -EWOULDBLOCK;
1745                         goto out;
1746                 }
1747
1748                 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1749                 set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1750                 sk_wait_event(sk, &timeo, dn_data_ready(sk, queue, flags, target));
1751                 clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1752                 finish_wait(sk_sleep(sk), &wait);
1753         }
1754
1755         skb_queue_walk_safe(queue, skb, n) {
1756                 unsigned int chunk = skb->len;
1757                 cb = DN_SKB_CB(skb);
1758
1759                 if ((chunk + copied) > size)
1760                         chunk = size - copied;
1761
1762                 if (memcpy_toiovec(msg->msg_iov, skb->data, chunk)) {
1763                         rv = -EFAULT;
1764                         break;
1765                 }
1766                 copied += chunk;
1767
1768                 if (!(flags & MSG_PEEK))
1769                         skb_pull(skb, chunk);
1770
1771                 eor = cb->nsp_flags & 0x40;
1772
1773                 if (skb->len == 0) {
1774                         skb_unlink(skb, queue);
1775                         kfree_skb(skb);
1776                         /*
1777                          * N.B. Don't refer to skb or cb after this point
1778                          * in loop.
1779                          */
1780                         if ((scp->flowloc_sw == DN_DONTSEND) && !dn_congested(sk)) {
1781                                 scp->flowloc_sw = DN_SEND;
1782                                 dn_nsp_send_link(sk, DN_SEND, 0);
1783                         }
1784                 }
1785
1786                 if (eor) {
1787                         if (sk->sk_type == SOCK_SEQPACKET)
1788                                 break;
1789                         if (!(flags & MSG_WAITALL))
1790                                 break;
1791                 }
1792
1793                 if (flags & MSG_OOB)
1794                         break;
1795
1796                 if (copied >= target)
1797                         break;
1798         }
1799
1800         rv = copied;
1801
1802
1803         if (eor && (sk->sk_type == SOCK_SEQPACKET))
1804                 msg->msg_flags |= MSG_EOR;
1805
1806 out:
1807         if (rv == 0)
1808                 rv = (flags & MSG_PEEK) ? -sk->sk_err : sock_error(sk);
1809
1810         if ((rv >= 0) && msg->msg_name) {
1811                 memcpy(msg->msg_name, &scp->peer, sizeof(struct sockaddr_dn));
1812                 msg->msg_namelen = sizeof(struct sockaddr_dn);
1813         }
1814
1815         release_sock(sk);
1816
1817         return rv;
1818 }
1819
1820
1821 static inline int dn_queue_too_long(struct dn_scp *scp, struct sk_buff_head *queue, int flags)
1822 {
1823         unsigned char fctype = scp->services_rem & NSP_FC_MASK;
1824         if (skb_queue_len(queue) >= scp->snd_window)
1825                 return 1;
1826         if (fctype != NSP_FC_NONE) {
1827                 if (flags & MSG_OOB) {
1828                         if (scp->flowrem_oth == 0)
1829                                 return 1;
1830                 } else {
1831                         if (scp->flowrem_dat == 0)
1832                                 return 1;
1833                 }
1834         }
1835         return 0;
1836 }
1837
1838 /*
1839  * The DECnet spec requires that the "routing layer" accepts packets which
1840  * are at least 230 bytes in size. This excludes any headers which the NSP
1841  * layer might add, so we always assume that we'll be using the maximal
1842  * length header on data packets. The variation in length is due to the
1843  * inclusion (or not) of the two 16 bit acknowledgement fields so it doesn't
1844  * make much practical difference.
1845  */
1846 unsigned int dn_mss_from_pmtu(struct net_device *dev, int mtu)
1847 {
1848         unsigned int mss = 230 - DN_MAX_NSP_DATA_HEADER;
1849         if (dev) {
1850                 struct dn_dev *dn_db = rcu_dereference_raw(dev->dn_ptr);
1851                 mtu -= LL_RESERVED_SPACE(dev);
1852                 if (dn_db->use_long)
1853                         mtu -= 21;
1854                 else
1855                         mtu -= 6;
1856                 mtu -= DN_MAX_NSP_DATA_HEADER;
1857         } else {
1858                 /*
1859                  * 21 = long header, 16 = guess at MAC header length
1860                  */
1861                 mtu -= (21 + DN_MAX_NSP_DATA_HEADER + 16);
1862         }
1863         if (mtu > mss)
1864                 mss = mtu;
1865         return mss;
1866 }
1867
1868 static inline unsigned int dn_current_mss(struct sock *sk, int flags)
1869 {
1870         struct dst_entry *dst = __sk_dst_get(sk);
1871         struct dn_scp *scp = DN_SK(sk);
1872         int mss_now = min_t(int, scp->segsize_loc, scp->segsize_rem);
1873
1874         /* Other data messages are limited to 16 bytes per packet */
1875         if (flags & MSG_OOB)
1876                 return 16;
1877
1878         /* This works out the maximum size of segment we can send out */
1879         if (dst) {
1880                 u32 mtu = dst_mtu(dst);
1881                 mss_now = min_t(int, dn_mss_from_pmtu(dst->dev, mtu), mss_now);
1882         }
1883
1884         return mss_now;
1885 }
1886
1887 /*
1888  * N.B. We get the timeout wrong here, but then we always did get it
1889  * wrong before and this is another step along the road to correcting
1890  * it. It ought to get updated each time we pass through the routine,
1891  * but in practise it probably doesn't matter too much for now.
1892  */
1893 static inline struct sk_buff *dn_alloc_send_pskb(struct sock *sk,
1894                               unsigned long datalen, int noblock,
1895                               int *errcode)
1896 {
1897         struct sk_buff *skb = sock_alloc_send_skb(sk, datalen,
1898                                                    noblock, errcode);
1899         if (skb) {
1900                 skb->protocol = htons(ETH_P_DNA_RT);
1901                 skb->pkt_type = PACKET_OUTGOING;
1902         }
1903         return skb;
1904 }
1905
1906 static int dn_sendmsg(struct kiocb *iocb, struct socket *sock,
1907                       struct msghdr *msg, size_t size)
1908 {
1909         struct sock *sk = sock->sk;
1910         struct dn_scp *scp = DN_SK(sk);
1911         size_t mss;
1912         struct sk_buff_head *queue = &scp->data_xmit_queue;
1913         int flags = msg->msg_flags;
1914         int err = 0;
1915         size_t sent = 0;
1916         int addr_len = msg->msg_namelen;
1917         struct sockaddr_dn *addr = (struct sockaddr_dn *)msg->msg_name;
1918         struct sk_buff *skb = NULL;
1919         struct dn_skb_cb *cb;
1920         size_t len;
1921         unsigned char fctype;
1922         long timeo;
1923
1924         if (flags & ~(MSG_TRYHARD|MSG_OOB|MSG_DONTWAIT|MSG_EOR|MSG_NOSIGNAL|MSG_MORE|MSG_CMSG_COMPAT))
1925                 return -EOPNOTSUPP;
1926
1927         if (addr_len && (addr_len != sizeof(struct sockaddr_dn)))
1928                 return -EINVAL;
1929
1930         lock_sock(sk);
1931         timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
1932         /*
1933          * The only difference between stream sockets and sequenced packet
1934          * sockets is that the stream sockets always behave as if MSG_EOR
1935          * has been set.
1936          */
1937         if (sock->type == SOCK_STREAM) {
1938                 if (flags & MSG_EOR) {
1939                         err = -EINVAL;
1940                         goto out;
1941                 }
1942                 flags |= MSG_EOR;
1943         }
1944
1945
1946         err = dn_check_state(sk, addr, addr_len, &timeo, flags);
1947         if (err)
1948                 goto out_err;
1949
1950         if (sk->sk_shutdown & SEND_SHUTDOWN) {
1951                 err = -EPIPE;
1952                 if (!(flags & MSG_NOSIGNAL))
1953                         send_sig(SIGPIPE, current, 0);
1954                 goto out_err;
1955         }
1956
1957         if ((flags & MSG_TRYHARD) && sk->sk_dst_cache)
1958                 dst_negative_advice(sk);
1959
1960         mss = scp->segsize_rem;
1961         fctype = scp->services_rem & NSP_FC_MASK;
1962
1963         mss = dn_current_mss(sk, flags);
1964
1965         if (flags & MSG_OOB) {
1966                 queue = &scp->other_xmit_queue;
1967                 if (size > mss) {
1968                         err = -EMSGSIZE;
1969                         goto out;
1970                 }
1971         }
1972
1973         scp->persist_fxn = dn_nsp_xmit_timeout;
1974
1975         while(sent < size) {
1976                 err = sock_error(sk);
1977                 if (err)
1978                         goto out;
1979
1980                 if (signal_pending(current)) {
1981                         err = sock_intr_errno(timeo);
1982                         goto out;
1983                 }
1984
1985                 /*
1986                  * Calculate size that we wish to send.
1987                  */
1988                 len = size - sent;
1989
1990                 if (len > mss)
1991                         len = mss;
1992
1993                 /*
1994                  * Wait for queue size to go down below the window
1995                  * size.
1996                  */
1997                 if (dn_queue_too_long(scp, queue, flags)) {
1998                         DEFINE_WAIT(wait);
1999
2000                         if (flags & MSG_DONTWAIT) {
2001                                 err = -EWOULDBLOCK;
2002                                 goto out;
2003                         }
2004
2005                         prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2006                         set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
2007                         sk_wait_event(sk, &timeo,
2008                                       !dn_queue_too_long(scp, queue, flags));
2009                         clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
2010                         finish_wait(sk_sleep(sk), &wait);
2011                         continue;
2012                 }
2013
2014                 /*
2015                  * Get a suitably sized skb.
2016                  * 64 is a bit of a hack really, but its larger than any
2017                  * link-layer headers and has served us well as a good
2018                  * guess as to their real length.
2019                  */
2020                 skb = dn_alloc_send_pskb(sk, len + 64 + DN_MAX_NSP_DATA_HEADER,
2021                                          flags & MSG_DONTWAIT, &err);
2022
2023                 if (err)
2024                         break;
2025
2026                 if (!skb)
2027                         continue;
2028
2029                 cb = DN_SKB_CB(skb);
2030
2031                 skb_reserve(skb, 64 + DN_MAX_NSP_DATA_HEADER);
2032
2033                 if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) {
2034                         err = -EFAULT;
2035                         goto out;
2036                 }
2037
2038                 if (flags & MSG_OOB) {
2039                         cb->nsp_flags = 0x30;
2040                         if (fctype != NSP_FC_NONE)
2041                                 scp->flowrem_oth--;
2042                 } else {
2043                         cb->nsp_flags = 0x00;
2044                         if (scp->seg_total == 0)
2045                                 cb->nsp_flags |= 0x20;
2046
2047                         scp->seg_total += len;
2048
2049                         if (((sent + len) == size) && (flags & MSG_EOR)) {
2050                                 cb->nsp_flags |= 0x40;
2051                                 scp->seg_total = 0;
2052                                 if (fctype == NSP_FC_SCMC)
2053                                         scp->flowrem_dat--;
2054                         }
2055                         if (fctype == NSP_FC_SRC)
2056                                 scp->flowrem_dat--;
2057                 }
2058
2059                 sent += len;
2060                 dn_nsp_queue_xmit(sk, skb, sk->sk_allocation, flags & MSG_OOB);
2061                 skb = NULL;
2062
2063                 scp->persist = dn_nsp_persist(sk);
2064
2065         }
2066 out:
2067
2068         kfree_skb(skb);
2069
2070         release_sock(sk);
2071
2072         return sent ? sent : err;
2073
2074 out_err:
2075         err = sk_stream_error(sk, flags, err);
2076         release_sock(sk);
2077         return err;
2078 }
2079
2080 static int dn_device_event(struct notifier_block *this, unsigned long event,
2081                         void *ptr)
2082 {
2083         struct net_device *dev = (struct net_device *)ptr;
2084
2085         if (!net_eq(dev_net(dev), &init_net))
2086                 return NOTIFY_DONE;
2087
2088         switch (event) {
2089         case NETDEV_UP:
2090                 dn_dev_up(dev);
2091                 break;
2092         case NETDEV_DOWN:
2093                 dn_dev_down(dev);
2094                 break;
2095         default:
2096                 break;
2097         }
2098
2099         return NOTIFY_DONE;
2100 }
2101
2102 static struct notifier_block dn_dev_notifier = {
2103         .notifier_call = dn_device_event,
2104 };
2105
2106 extern int dn_route_rcv(struct sk_buff *, struct net_device *, struct packet_type *, struct net_device *);
2107
2108 static struct packet_type dn_dix_packet_type __read_mostly = {
2109         .type =         cpu_to_be16(ETH_P_DNA_RT),
2110         .func =         dn_route_rcv,
2111 };
2112
2113 #ifdef CONFIG_PROC_FS
2114 struct dn_iter_state {
2115         int bucket;
2116 };
2117
2118 static struct sock *dn_socket_get_first(struct seq_file *seq)
2119 {
2120         struct dn_iter_state *state = seq->private;
2121         struct sock *n = NULL;
2122
2123         for(state->bucket = 0;
2124             state->bucket < DN_SK_HASH_SIZE;
2125             ++state->bucket) {
2126                 n = sk_head(&dn_sk_hash[state->bucket]);
2127                 if (n)
2128                         break;
2129         }
2130
2131         return n;
2132 }
2133
2134 static struct sock *dn_socket_get_next(struct seq_file *seq,
2135                                        struct sock *n)
2136 {
2137         struct dn_iter_state *state = seq->private;
2138
2139         n = sk_next(n);
2140 try_again:
2141         if (n)
2142                 goto out;
2143         if (++state->bucket >= DN_SK_HASH_SIZE)
2144                 goto out;
2145         n = sk_head(&dn_sk_hash[state->bucket]);
2146         goto try_again;
2147 out:
2148         return n;
2149 }
2150
2151 static struct sock *socket_get_idx(struct seq_file *seq, loff_t *pos)
2152 {
2153         struct sock *sk = dn_socket_get_first(seq);
2154
2155         if (sk) {
2156                 while(*pos && (sk = dn_socket_get_next(seq, sk)))
2157                         --*pos;
2158         }
2159         return *pos ? NULL : sk;
2160 }
2161
2162 static void *dn_socket_get_idx(struct seq_file *seq, loff_t pos)
2163 {
2164         void *rc;
2165         read_lock_bh(&dn_hash_lock);
2166         rc = socket_get_idx(seq, &pos);
2167         if (!rc) {
2168                 read_unlock_bh(&dn_hash_lock);
2169         }
2170         return rc;
2171 }
2172
2173 static void *dn_socket_seq_start(struct seq_file *seq, loff_t *pos)
2174 {
2175         return *pos ? dn_socket_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2176 }
2177
2178 static void *dn_socket_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2179 {
2180         void *rc;
2181
2182         if (v == SEQ_START_TOKEN) {
2183                 rc = dn_socket_get_idx(seq, 0);
2184                 goto out;
2185         }
2186
2187         rc = dn_socket_get_next(seq, v);
2188         if (rc)
2189                 goto out;
2190         read_unlock_bh(&dn_hash_lock);
2191 out:
2192         ++*pos;
2193         return rc;
2194 }
2195
2196 static void dn_socket_seq_stop(struct seq_file *seq, void *v)
2197 {
2198         if (v && v != SEQ_START_TOKEN)
2199                 read_unlock_bh(&dn_hash_lock);
2200 }
2201
2202 #define IS_NOT_PRINTABLE(x) ((x) < 32 || (x) > 126)
2203
2204 static void dn_printable_object(struct sockaddr_dn *dn, unsigned char *buf)
2205 {
2206         int i;
2207
2208         switch (le16_to_cpu(dn->sdn_objnamel)) {
2209         case 0:
2210                 sprintf(buf, "%d", dn->sdn_objnum);
2211                 break;
2212         default:
2213                 for (i = 0; i < le16_to_cpu(dn->sdn_objnamel); i++) {
2214                         buf[i] = dn->sdn_objname[i];
2215                         if (IS_NOT_PRINTABLE(buf[i]))
2216                                 buf[i] = '.';
2217                 }
2218                 buf[i] = 0;
2219         }
2220 }
2221
2222 static char *dn_state2asc(unsigned char state)
2223 {
2224         switch (state) {
2225         case DN_O:
2226                 return "OPEN";
2227         case DN_CR:
2228                 return "  CR";
2229         case DN_DR:
2230                 return "  DR";
2231         case DN_DRC:
2232                 return " DRC";
2233         case DN_CC:
2234                 return "  CC";
2235         case DN_CI:
2236                 return "  CI";
2237         case DN_NR:
2238                 return "  NR";
2239         case DN_NC:
2240                 return "  NC";
2241         case DN_CD:
2242                 return "  CD";
2243         case DN_RJ:
2244                 return "  RJ";
2245         case DN_RUN:
2246                 return " RUN";
2247         case DN_DI:
2248                 return "  DI";
2249         case DN_DIC:
2250                 return " DIC";
2251         case DN_DN:
2252                 return "  DN";
2253         case DN_CL:
2254                 return "  CL";
2255         case DN_CN:
2256                 return "  CN";
2257         }
2258
2259         return "????";
2260 }
2261
2262 static inline void dn_socket_format_entry(struct seq_file *seq, struct sock *sk)
2263 {
2264         struct dn_scp *scp = DN_SK(sk);
2265         char buf1[DN_ASCBUF_LEN];
2266         char buf2[DN_ASCBUF_LEN];
2267         char local_object[DN_MAXOBJL+3];
2268         char remote_object[DN_MAXOBJL+3];
2269
2270         dn_printable_object(&scp->addr, local_object);
2271         dn_printable_object(&scp->peer, remote_object);
2272
2273         seq_printf(seq,
2274                    "%6s/%04X %04d:%04d %04d:%04d %01d %-16s "
2275                    "%6s/%04X %04d:%04d %04d:%04d %01d %-16s %4s %s\n",
2276                    dn_addr2asc(le16_to_cpu(dn_saddr2dn(&scp->addr)), buf1),
2277                    scp->addrloc,
2278                    scp->numdat,
2279                    scp->numoth,
2280                    scp->ackxmt_dat,
2281                    scp->ackxmt_oth,
2282                    scp->flowloc_sw,
2283                    local_object,
2284                    dn_addr2asc(le16_to_cpu(dn_saddr2dn(&scp->peer)), buf2),
2285                    scp->addrrem,
2286                    scp->numdat_rcv,
2287                    scp->numoth_rcv,
2288                    scp->ackrcv_dat,
2289                    scp->ackrcv_oth,
2290                    scp->flowrem_sw,
2291                    remote_object,
2292                    dn_state2asc(scp->state),
2293                    ((scp->accept_mode == ACC_IMMED) ? "IMMED" : "DEFER"));
2294 }
2295
2296 static int dn_socket_seq_show(struct seq_file *seq, void *v)
2297 {
2298         if (v == SEQ_START_TOKEN) {
2299                 seq_puts(seq, "Local                                              Remote\n");
2300         } else {
2301                 dn_socket_format_entry(seq, v);
2302         }
2303         return 0;
2304 }
2305
2306 static const struct seq_operations dn_socket_seq_ops = {
2307         .start  = dn_socket_seq_start,
2308         .next   = dn_socket_seq_next,
2309         .stop   = dn_socket_seq_stop,
2310         .show   = dn_socket_seq_show,
2311 };
2312
2313 static int dn_socket_seq_open(struct inode *inode, struct file *file)
2314 {
2315         return seq_open_private(file, &dn_socket_seq_ops,
2316                         sizeof(struct dn_iter_state));
2317 }
2318
2319 static const struct file_operations dn_socket_seq_fops = {
2320         .owner          = THIS_MODULE,
2321         .open           = dn_socket_seq_open,
2322         .read           = seq_read,
2323         .llseek         = seq_lseek,
2324         .release        = seq_release_private,
2325 };
2326 #endif
2327
2328 static const struct net_proto_family    dn_family_ops = {
2329         .family =       AF_DECnet,
2330         .create =       dn_create,
2331         .owner  =       THIS_MODULE,
2332 };
2333
2334 static const struct proto_ops dn_proto_ops = {
2335         .family =       AF_DECnet,
2336         .owner =        THIS_MODULE,
2337         .release =      dn_release,
2338         .bind =         dn_bind,
2339         .connect =      dn_connect,
2340         .socketpair =   sock_no_socketpair,
2341         .accept =       dn_accept,
2342         .getname =      dn_getname,
2343         .poll =         dn_poll,
2344         .ioctl =        dn_ioctl,
2345         .listen =       dn_listen,
2346         .shutdown =     dn_shutdown,
2347         .setsockopt =   dn_setsockopt,
2348         .getsockopt =   dn_getsockopt,
2349         .sendmsg =      dn_sendmsg,
2350         .recvmsg =      dn_recvmsg,
2351         .mmap =         sock_no_mmap,
2352         .sendpage =     sock_no_sendpage,
2353 };
2354
2355 void dn_register_sysctl(void);
2356 void dn_unregister_sysctl(void);
2357
2358 MODULE_DESCRIPTION("The Linux DECnet Network Protocol");
2359 MODULE_AUTHOR("Linux DECnet Project Team");
2360 MODULE_LICENSE("GPL");
2361 MODULE_ALIAS_NETPROTO(PF_DECnet);
2362
2363 static char banner[] __initdata = KERN_INFO "NET4: DECnet for Linux: V.2.5.68s (C) 1995-2003 Linux DECnet Project Team\n";
2364
2365 static int __init decnet_init(void)
2366 {
2367         int rc;
2368
2369         printk(banner);
2370
2371         rc = proto_register(&dn_proto, 1);
2372         if (rc != 0)
2373                 goto out;
2374
2375         dn_neigh_init();
2376         dn_dev_init();
2377         dn_route_init();
2378         dn_fib_init();
2379
2380         sock_register(&dn_family_ops);
2381         dev_add_pack(&dn_dix_packet_type);
2382         register_netdevice_notifier(&dn_dev_notifier);
2383
2384         proc_create("decnet", S_IRUGO, init_net.proc_net, &dn_socket_seq_fops);
2385         dn_register_sysctl();
2386 out:
2387         return rc;
2388
2389 }
2390 module_init(decnet_init);
2391
2392 /*
2393  * Prevent DECnet module unloading until its fixed properly.
2394  * Requires an audit of the code to check for memory leaks and
2395  * initialisation problems etc.
2396  */
2397 #if 0
2398 static void __exit decnet_exit(void)
2399 {
2400         sock_unregister(AF_DECnet);
2401         rtnl_unregister_all(PF_DECnet);
2402         dev_remove_pack(&dn_dix_packet_type);
2403
2404         dn_unregister_sysctl();
2405
2406         unregister_netdevice_notifier(&dn_dev_notifier);
2407
2408         dn_route_cleanup();
2409         dn_dev_cleanup();
2410         dn_neigh_cleanup();
2411         dn_fib_cleanup();
2412
2413         remove_proc_entry("decnet", init_net.proc_net);
2414
2415         proto_unregister(&dn_proto);
2416
2417         rcu_barrier_bh(); /* Wait for completion of call_rcu_bh()'s */
2418 }
2419 module_exit(decnet_exit);
2420 #endif