net/decnet/af_decnet.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2
   3 /*
   4  * DECnet       An implementation of the DECnet protocol suite for the LINUX
   5  *              operating system.  DECnet is implemented using the  BSD Socket
   6  *              interface as the means of communication with the user level.
   7  *
   8  *              DECnet Socket Layer Interface
   9  *
  10  * Authors:     Eduardo Marcelo Serrat <emserrat@geocities.com>
  11  *              Patrick Caulfield <patrick@pandh.demon.co.uk>
  12  *
  13  * Changes:
  14  *        Steve Whitehouse: Copied from Eduardo Serrat and Patrick Caulfield's
  15  *                          version of the code. Original copyright preserved
  16  *                          below.
  17  *        Steve Whitehouse: Some bug fixes, cleaning up some code to make it
  18  *                          compatible with my routing layer.
  19  *        Steve Whitehouse: Merging changes from Eduardo Serrat and Patrick
  20  *                          Caulfield.
  21  *        Steve Whitehouse: Further bug fixes, checking module code still works
  22  *                          with new routing layer.
  23  *        Steve Whitehouse: Additional set/get_sockopt() calls.
  24  *        Steve Whitehouse: Fixed TIOCINQ ioctl to be same as Eduardo's new
  25  *                          code.
  26  *        Steve Whitehouse: recvmsg() changed to try and behave in a POSIX like
  27  *                          way. Didn't manage it entirely, but its better.
  28  *        Steve Whitehouse: ditto for sendmsg().
  29  *        Steve Whitehouse: A selection of bug fixes to various things.
  30  *        Steve Whitehouse: Added TIOCOUTQ ioctl.
  31  *        Steve Whitehouse: Fixes to username2sockaddr & sockaddr2username.
  32  *        Steve Whitehouse: Fixes to connect() error returns.
  33  *       Patrick Caulfield: Fixes to delayed acceptance logic.
  34  *         David S. Miller: New socket locking
  35  *        Steve Whitehouse: Socket list hashing/locking
  36  *         Arnaldo C. Melo: use capable, not suser
  37  *        Steve Whitehouse: Removed unused code. Fix to use sk->allocation
  38  *                          when required.
  39  *       Patrick Caulfield: /proc/net/decnet now has object name/number
  40  *        Steve Whitehouse: Fixed local port allocation, hashed sk list
  41  *          Matthew Wilcox: Fixes for dn_ioctl()
  42  *        Steve Whitehouse: New connect/accept logic to allow timeouts and
  43  *                          prepare for sendpage etc.
  44  */
  45
  46
  47 /******************************************************************************
  48     (c) 1995-1998 E.M. Serrat           emserrat@geocities.com
  49
  50
  51 HISTORY:
  52
  53 Version           Kernel     Date       Author/Comments
  54 -------           ------     ----       ---------------
  55 Version 0.0.1     2.0.30    01-dic-97   Eduardo Marcelo Serrat
  56                                         (emserrat@geocities.com)
  57
  58                                         First Development of DECnet Socket La-
  59                                         yer for Linux. Only supports outgoing
  60                                         connections.
  61
  62 Version 0.0.2     2.1.105   20-jun-98   Patrick J. Caulfield
  63                                         (patrick@pandh.demon.co.uk)
  64
  65                                         Port to new kernel development version.
  66
  67 Version 0.0.3     2.1.106   25-jun-98   Eduardo Marcelo Serrat
  68                                         (emserrat@geocities.com)
  69                                         _
  70                                         Added support for incoming connections
  71                                         so we can start developing server apps
  72                                         on Linux.
  73                                         -
  74                                         Module Support
  75 Version 0.0.4     2.1.109   21-jul-98   Eduardo Marcelo Serrat
  76                                        (emserrat@geocities.com)
  77                                        _
  78                                         Added support for X11R6.4. Now we can
  79                                         use DECnet transport for X on Linux!!!
  80                                        -
  81 Version 0.0.5    2.1.110   01-aug-98   Eduardo Marcelo Serrat
  82                                        (emserrat@geocities.com)
  83                                        Removed bugs on flow control
  84                                        Removed bugs on incoming accessdata
  85                                        order
  86                                        -
  87 Version 0.0.6    2.1.110   07-aug-98   Eduardo Marcelo Serrat
  88                                        dn_recvmsg fixes
  89
  90                                         Patrick J. Caulfield
  91                                        dn_bind fixes
  92 *******************************************************************************/
  93
  94 #include <linux/module.h>
  95 #include <linux/errno.h>
  96 #include <linux/types.h>
  97 #include <linux/slab.h>
  98 #include <linux/socket.h>
  99 #include <linux/in.h>
 100 #include <linux/kernel.h>
 101 #include <linux/sched/signal.h>
 102 #include <linux/timer.h>
 103 #include <linux/string.h>
 104 #include <linux/sockios.h>
 105 #include <linux/net.h>
 106 #include <linux/netdevice.h>
 107 #include <linux/inet.h>
 108 #include <linux/route.h>
 109 #include <linux/netfilter.h>
 110 #include <linux/seq_file.h>
 111 #include <net/sock.h>
 112 #include <net/tcp_states.h>
 113 #include <net/flow.h>
 114 #include <asm/ioctls.h>
 115 #include <linux/capability.h>
 116 #include <linux/mm.h>
 117 #include <linux/interrupt.h>
 118 #include <linux/proc_fs.h>
 119 #include <linux/stat.h>
 120 #include <linux/init.h>
 121 #include <linux/poll.h>
 122 #include <linux/jiffies.h>
 123 #include <net/net_namespace.h>
 124 #include <net/neighbour.h>
 125 #include <net/dst.h>
 126 #include <net/fib_rules.h>
 127 #include <net/tcp.h>
 128 #include <net/dn.h>
 129 #include <net/dn_nsp.h>
 130 #include <net/dn_dev.h>
 131 #include <net/dn_route.h>
 132 #include <net/dn_fib.h>
 133 #include <net/dn_neigh.h>
 134
 135 struct dn_sock {
 136         struct sock sk;
 137         struct dn_scp scp;
 138 };
 139
 140 static void dn_keepalive(struct sock *sk);
 141
 142 #define DN_SK_HASH_SHIFT 8
 143 #define DN_SK_HASH_SIZE (1 << DN_SK_HASH_SHIFT)
 144 #define DN_SK_HASH_MASK (DN_SK_HASH_SIZE - 1)
 145
 146
 147 static const struct proto_ops dn_proto_ops;
 148 static DEFINE_RWLOCK(dn_hash_lock);
 149 static struct hlist_head dn_sk_hash[DN_SK_HASH_SIZE];
 150 static struct hlist_head dn_wild_sk;
 151 static atomic_long_t decnet_memory_allocated;
 152
 153 static int __dn_setsockopt(struct socket *sock, int level, int optname,
 154                 sockptr_t optval, unsigned int optlen, int flags);
 155 static int __dn_getsockopt(struct socket *sock, int level, int optname, char __user *optval, int __user *optlen, int flags);
 156
 157 static struct hlist_head *dn_find_list(struct sock *sk)
 158 {
 159         struct dn_scp *scp = DN_SK(sk);
 160
 161         if (scp->addr.sdn_flags & SDF_WILD)
 162                 return hlist_empty(&dn_wild_sk) ? &dn_wild_sk : NULL;
 163
 164         return &dn_sk_hash[le16_to_cpu(scp->addrloc) & DN_SK_HASH_MASK];
 165 }
 166
 167 /*
 168  * Valid ports are those greater than zero and not already in use.
 169  */
 170 static int check_port(__le16 port)
 171 {
 172         struct sock *sk;
 173
 174         if (port == 0)
 175                 return -1;
 176
 177         sk_for_each(sk, &dn_sk_hash[le16_to_cpu(port) & DN_SK_HASH_MASK]) {
 178                 struct dn_scp *scp = DN_SK(sk);
 179                 if (scp->addrloc == port)
 180                         return -1;
 181         }
 182         return 0;
 183 }
 184
 185 static unsigned short port_alloc(struct sock *sk)
 186 {
 187         struct dn_scp *scp = DN_SK(sk);
 188         static unsigned short port = 0x2000;
 189         unsigned short i_port = port;
 190
 191         while(check_port(cpu_to_le16(++port)) != 0) {
 192                 if (port == i_port)
 193                         return 0;
 194         }
 195
 196         scp->addrloc = cpu_to_le16(port);
 197
 198         return 1;
 199 }
 200
 201 /*
 202  * Since this is only ever called from user
 203  * level, we don't need a write_lock() version
 204  * of this.
 205  */
 206 static int dn_hash_sock(struct sock *sk)
 207 {
 208         struct dn_scp *scp = DN_SK(sk);
 209         struct hlist_head *list;
 210         int rv = -EUSERS;
 211
 212         BUG_ON(sk_hashed(sk));
 213
 214         write_lock_bh(&dn_hash_lock);
 215
 216         if (!scp->addrloc && !port_alloc(sk))
 217                 goto out;
 218
 219         rv = -EADDRINUSE;
 220         if ((list = dn_find_list(sk)) == NULL)
 221                 goto out;
 222
 223         sk_add_node(sk, list);
 224         rv = 0;
 225 out:
 226         write_unlock_bh(&dn_hash_lock);
 227         return rv;
 228 }
 229
 230 static void dn_unhash_sock(struct sock *sk)
 231 {
 232         write_lock(&dn_hash_lock);
 233         sk_del_node_init(sk);
 234         write_unlock(&dn_hash_lock);
 235 }
 236
 237 static void dn_unhash_sock_bh(struct sock *sk)
 238 {
 239         write_lock_bh(&dn_hash_lock);
 240         sk_del_node_init(sk);
 241         write_unlock_bh(&dn_hash_lock);
 242 }
 243
 244 static struct hlist_head *listen_hash(struct sockaddr_dn *addr)
 245 {
 246         int i;
 247         unsigned int hash = addr->sdn_objnum;
 248
 249         if (hash == 0) {
 250                 hash = addr->sdn_objnamel;
 251                 for(i = 0; i < le16_to_cpu(addr->sdn_objnamel); i++) {
 252                         hash ^= addr->sdn_objname[i];
 253                         hash ^= (hash << 3);
 254                 }
 255         }
 256
 257         return &dn_sk_hash[hash & DN_SK_HASH_MASK];
 258 }
 259
 260 /*
 261  * Called to transform a socket from bound (i.e. with a local address)
 262  * into a listening socket (doesn't need a local port number) and rehashes
 263  * based upon the object name/number.
 264  */
 265 static void dn_rehash_sock(struct sock *sk)
 266 {
 267         struct hlist_head *list;
 268         struct dn_scp *scp = DN_SK(sk);
 269
 270         if (scp->addr.sdn_flags & SDF_WILD)
 271                 return;
 272
 273         write_lock_bh(&dn_hash_lock);
 274         sk_del_node_init(sk);
 275         DN_SK(sk)->addrloc = 0;
 276         list = listen_hash(&DN_SK(sk)->addr);
 277         sk_add_node(sk, list);
 278         write_unlock_bh(&dn_hash_lock);
 279 }
 280
 281 int dn_sockaddr2username(struct sockaddr_dn *sdn, unsigned char *buf, unsigned char type)
 282 {
 283         int len = 2;
 284
 285         *buf++ = type;
 286
 287         switch (type) {
 288         case 0:
 289                 *buf++ = sdn->sdn_objnum;
 290                 break;
 291         case 1:
 292                 *buf++ = 0;
 293                 *buf++ = le16_to_cpu(sdn->sdn_objnamel);
 294                 memcpy(buf, sdn->sdn_objname, le16_to_cpu(sdn->sdn_objnamel));
 295                 len = 3 + le16_to_cpu(sdn->sdn_objnamel);
 296                 break;
 297         case 2:
 298                 memset(buf, 0, 5);
 299                 buf += 5;
 300                 *buf++ = le16_to_cpu(sdn->sdn_objnamel);
 301                 memcpy(buf, sdn->sdn_objname, le16_to_cpu(sdn->sdn_objnamel));
 302                 len = 7 + le16_to_cpu(sdn->sdn_objnamel);
 303                 break;
 304         }
 305
 306         return len;
 307 }
 308
 309 /*
 310  * On reception of usernames, we handle types 1 and 0 for destination
 311  * addresses only. Types 2 and 4 are used for source addresses, but the
 312  * UIC, GIC are ignored and they are both treated the same way. Type 3
 313  * is never used as I've no idea what its purpose might be or what its
 314  * format is.
 315  */
 316 int dn_username2sockaddr(unsigned char *data, int len, struct sockaddr_dn *sdn, unsigned char *fmt)
 317 {
 318         unsigned char type;
 319         int size = len;
 320         int namel = 12;
 321
 322         sdn->sdn_objnum = 0;
 323         sdn->sdn_objnamel = cpu_to_le16(0);
 324         memset(sdn->sdn_objname, 0, DN_MAXOBJL);
 325
 326         if (len < 2)
 327                 return -1;
 328
 329         len -= 2;
 330         *fmt = *data++;
 331         type = *data++;
 332
 333         switch (*fmt) {
 334         case 0:
 335                 sdn->sdn_objnum = type;
 336                 return 2;
 337         case 1:
 338                 namel = 16;
 339                 break;
 340         case 2:
 341                 len  -= 4;
 342                 data += 4;
 343                 break;
 344         case 4:
 345                 len  -= 8;
 346                 data += 8;
 347                 break;
 348         default:
 349                 return -1;
 350         }
 351
 352         len -= 1;
 353
 354         if (len < 0)
 355                 return -1;
 356
 357         sdn->sdn_objnamel = cpu_to_le16(*data++);
 358         len -= le16_to_cpu(sdn->sdn_objnamel);
 359
 360         if ((len < 0) || (le16_to_cpu(sdn->sdn_objnamel) > namel))
 361                 return -1;
 362
 363         memcpy(sdn->sdn_objname, data, le16_to_cpu(sdn->sdn_objnamel));
 364
 365         return size - len;
 366 }
 367
 368 struct sock *dn_sklist_find_listener(struct sockaddr_dn *addr)
 369 {
 370         struct hlist_head *list = listen_hash(addr);
 371         struct sock *sk;
 372
 373         read_lock(&dn_hash_lock);
 374         sk_for_each(sk, list) {
 375                 struct dn_scp *scp = DN_SK(sk);
 376                 if (sk->sk_state != TCP_LISTEN)
 377                         continue;
 378                 if (scp->addr.sdn_objnum) {
 379                         if (scp->addr.sdn_objnum != addr->sdn_objnum)
 380                                 continue;
 381                 } else {
 382                         if (addr->sdn_objnum)
 383                                 continue;
 384                         if (scp->addr.sdn_objnamel != addr->sdn_objnamel)
 385                                 continue;
 386                         if (memcmp(scp->addr.sdn_objname, addr->sdn_objname, le16_to_cpu(addr->sdn_objnamel)) != 0)
 387                                 continue;
 388                 }
 389                 sock_hold(sk);
 390                 read_unlock(&dn_hash_lock);
 391                 return sk;
 392         }
 393
 394         sk = sk_head(&dn_wild_sk);
 395         if (sk) {
 396                 if (sk->sk_state == TCP_LISTEN)
 397                         sock_hold(sk);
 398                 else
 399                         sk = NULL;
 400         }
 401
 402         read_unlock(&dn_hash_lock);
 403         return sk;
 404 }
 405
 406 struct sock *dn_find_by_skb(struct sk_buff *skb)
 407 {
 408         struct dn_skb_cb *cb = DN_SKB_CB(skb);
 409         struct sock *sk;
 410         struct dn_scp *scp;
 411
 412         read_lock(&dn_hash_lock);
 413         sk_for_each(sk, &dn_sk_hash[le16_to_cpu(cb->dst_port) & DN_SK_HASH_MASK]) {
 414                 scp = DN_SK(sk);
 415                 if (cb->src != dn_saddr2dn(&scp->peer))
 416                         continue;
 417                 if (cb->dst_port != scp->addrloc)
 418                         continue;
 419                 if (scp->addrrem && (cb->src_port != scp->addrrem))
 420                         continue;
 421                 sock_hold(sk);
 422                 goto found;
 423         }
 424         sk = NULL;
 425 found:
 426         read_unlock(&dn_hash_lock);
 427         return sk;
 428 }
 429
 430
 431
 432 static void dn_destruct(struct sock *sk)
 433 {
 434         struct dn_scp *scp = DN_SK(sk);
 435
 436         skb_queue_purge(&scp->data_xmit_queue);
 437         skb_queue_purge(&scp->other_xmit_queue);
 438         skb_queue_purge(&scp->other_receive_queue);
 439
 440         dst_release(rcu_dereference_protected(sk->sk_dst_cache, 1));
 441 }
 442
 443 static unsigned long dn_memory_pressure;
 444
 445 static void dn_enter_memory_pressure(struct sock *sk)
 446 {
 447         if (!dn_memory_pressure) {
 448                 dn_memory_pressure = 1;
 449         }
 450 }
 451
 452 static struct proto dn_proto = {
 453         .name                   = "NSP",
 454         .owner                  = THIS_MODULE,
 455         .enter_memory_pressure  = dn_enter_memory_pressure,
 456         .memory_pressure        = &dn_memory_pressure,
 457         .memory_allocated       = &decnet_memory_allocated,
 458         .sysctl_mem             = sysctl_decnet_mem,
 459         .sysctl_wmem            = sysctl_decnet_wmem,
 460         .sysctl_rmem            = sysctl_decnet_rmem,
 461         .max_header             = DN_MAX_NSP_DATA_HEADER + 64,
 462         .obj_size               = sizeof(struct dn_sock),
 463 };
 464
 465 static struct sock *dn_alloc_sock(struct net *net, struct socket *sock, gfp_t gfp, int kern)
 466 {
 467         struct dn_scp *scp;
 468         struct sock *sk = sk_alloc(net, PF_DECnet, gfp, &dn_proto, kern);
 469
 470         if  (!sk)
 471                 goto out;
 472
 473         if (sock)
 474                 sock->ops = &dn_proto_ops;
 475         sock_init_data(sock, sk);
 476
 477         sk->sk_backlog_rcv = dn_nsp_backlog_rcv;
 478         sk->sk_destruct    = dn_destruct;
 479         sk->sk_no_check_tx = 1;
 480         sk->sk_family      = PF_DECnet;
 481         sk->sk_protocol    = 0;
 482         sk->sk_allocation  = gfp;
 483         sk->sk_sndbuf      = sysctl_decnet_wmem[1];
 484         sk->sk_rcvbuf      = sysctl_decnet_rmem[1];
 485
 486         /* Initialization of DECnet Session Control Port                */
 487         scp = DN_SK(sk);
 488         scp->state      = DN_O;         /* Open                 */
 489         scp->numdat     = 1;            /* Next data seg to tx  */
 490         scp->numoth     = 1;            /* Next oth data to tx  */
 491         scp->ackxmt_dat = 0;            /* Last data seg ack'ed */
 492         scp->ackxmt_oth = 0;            /* Last oth data ack'ed */
 493         scp->ackrcv_dat = 0;            /* Highest data ack recv*/
 494         scp->ackrcv_oth = 0;            /* Last oth data ack rec*/
 495         scp->flowrem_sw = DN_SEND;
 496         scp->flowloc_sw = DN_SEND;
 497         scp->flowrem_dat = 0;
 498         scp->flowrem_oth = 1;
 499         scp->flowloc_dat = 0;
 500         scp->flowloc_oth = 1;
 501         scp->services_rem = 0;
 502         scp->services_loc = 1 | NSP_FC_NONE;
 503         scp->info_rem = 0;
 504         scp->info_loc = 0x03; /* NSP version 4.1 */
 505         scp->segsize_rem = 230 - DN_MAX_NSP_DATA_HEADER; /* Default: Updated by remote segsize */
 506         scp->nonagle = 0;
 507         scp->multi_ireq = 1;
 508         scp->accept_mode = ACC_IMMED;
 509         scp->addr.sdn_family    = AF_DECnet;
 510         scp->peer.sdn_family    = AF_DECnet;
 511         scp->accessdata.acc_accl = 5;
 512         memcpy(scp->accessdata.acc_acc, "LINUX", 5);
 513
 514         scp->max_window   = NSP_MAX_WINDOW;
 515         scp->snd_window   = NSP_MIN_WINDOW;
 516         scp->nsp_srtt     = NSP_INITIAL_SRTT;
 517         scp->nsp_rttvar   = NSP_INITIAL_RTTVAR;
 518         scp->nsp_rxtshift = 0;
 519
 520         skb_queue_head_init(&scp->data_xmit_queue);
 521         skb_queue_head_init(&scp->other_xmit_queue);
 522         skb_queue_head_init(&scp->other_receive_queue);
 523
 524         scp->persist = 0;
 525         scp->persist_fxn = NULL;
 526         scp->keepalive = 10 * HZ;
 527         scp->keepalive_fxn = dn_keepalive;
 528
 529         dn_start_slow_timer(sk);
 530 out:
 531         return sk;
 532 }
 533
 534 /*
 535  * Keepalive timer.
 536  * FIXME: Should respond to SO_KEEPALIVE etc.
 537  */
 538 static void dn_keepalive(struct sock *sk)
 539 {
 540         struct dn_scp *scp = DN_SK(sk);
 541
 542         /*
 543          * By checking the other_data transmit queue is empty
 544          * we are double checking that we are not sending too
 545          * many of these keepalive frames.
 546          */
 547         if (skb_queue_empty(&scp->other_xmit_queue))
 548                 dn_nsp_send_link(sk, DN_NOCHANGE, 0);
 549 }
 550
 551
 552 /*
 553  * Timer for shutdown/destroyed sockets.
 554  * When socket is dead & no packets have been sent for a
 555  * certain amount of time, they are removed by this
 556  * routine. Also takes care of sending out DI & DC
 557  * frames at correct times.
 558  */
 559 int dn_destroy_timer(struct sock *sk)
 560 {
 561         struct dn_scp *scp = DN_SK(sk);
 562
 563         scp->persist = dn_nsp_persist(sk);
 564
 565         switch (scp->state) {
 566         case DN_DI:
 567                 dn_nsp_send_disc(sk, NSP_DISCINIT, 0, GFP_ATOMIC);
 568                 if (scp->nsp_rxtshift >= decnet_di_count)
 569                         scp->state = DN_CN;
 570                 return 0;
 571
 572         case DN_DR:
 573                 dn_nsp_send_disc(sk, NSP_DISCINIT, 0, GFP_ATOMIC);
 574                 if (scp->nsp_rxtshift >= decnet_dr_count)
 575                         scp->state = DN_DRC;
 576                 return 0;
 577
 578         case DN_DN:
 579                 if (scp->nsp_rxtshift < decnet_dn_count) {
 580                         /* printk(KERN_DEBUG "dn_destroy_timer: DN\n"); */
 581                         dn_nsp_send_disc(sk, NSP_DISCCONF, NSP_REASON_DC,
 582                                          GFP_ATOMIC);
 583                         return 0;
 584                 }
 585         }
 586
 587         scp->persist = (HZ * decnet_time_wait);
 588
 589         if (sk->sk_socket)
 590                 return 0;
 591
 592         if (time_after_eq(jiffies, scp->stamp + HZ * decnet_time_wait)) {
 593                 dn_unhash_sock(sk);
 594                 sock_put(sk);
 595                 return 1;
 596         }
 597
 598         return 0;
 599 }
 600
 601 static void dn_destroy_sock(struct sock *sk)
 602 {
 603         struct dn_scp *scp = DN_SK(sk);
 604
 605         scp->nsp_rxtshift = 0; /* reset back off */
 606
 607         if (sk->sk_socket) {
 608                 if (sk->sk_socket->state != SS_UNCONNECTED)
 609                         sk->sk_socket->state = SS_DISCONNECTING;
 610         }
 611
 612         sk->sk_state = TCP_CLOSE;
 613
 614         switch (scp->state) {
 615         case DN_DN:
 616                 dn_nsp_send_disc(sk, NSP_DISCCONF, NSP_REASON_DC,
 617                                  sk->sk_allocation);
 618                 scp->persist_fxn = dn_destroy_timer;
 619                 scp->persist = dn_nsp_persist(sk);
 620                 break;
 621         case DN_CR:
 622                 scp->state = DN_DR;
 623                 goto disc_reject;
 624         case DN_RUN:
 625                 scp->state = DN_DI;
 626                 fallthrough;
 627         case DN_DI:
 628         case DN_DR:
 629 disc_reject:
 630                 dn_nsp_send_disc(sk, NSP_DISCINIT, 0, sk->sk_allocation);
 631                 fallthrough;
 632         case DN_NC:
 633         case DN_NR:
 634         case DN_RJ:
 635         case DN_DIC:
 636         case DN_CN:
 637         case DN_DRC:
 638         case DN_CI:
 639         case DN_CD:
 640                 scp->persist_fxn = dn_destroy_timer;
 641                 scp->persist = dn_nsp_persist(sk);
 642                 break;
 643         default:
 644                 printk(KERN_DEBUG "DECnet: dn_destroy_sock passed socket in invalid state\n");
 645                 fallthrough;
 646         case DN_O:
 647                 dn_stop_slow_timer(sk);
 648
 649                 dn_unhash_sock_bh(sk);
 650                 sock_put(sk);
 651
 652                 break;
 653         }
 654 }
 655
 656 char *dn_addr2asc(__u16 addr, char *buf)
 657 {
 658         unsigned short node, area;
 659
 660         node = addr & 0x03ff;
 661         area = addr >> 10;
 662         sprintf(buf, "%hd.%hd", area, node);
 663
 664         return buf;
 665 }
 666
 667
 668
 669 static int dn_create(struct net *net, struct socket *sock, int protocol,
 670                      int kern)
 671 {
 672         struct sock *sk;
 673
 674         if (protocol < 0 || protocol > U8_MAX)
 675                 return -EINVAL;
 676
 677         if (!net_eq(net, &init_net))
 678                 return -EAFNOSUPPORT;
 679
 680         switch (sock->type) {
 681         case SOCK_SEQPACKET:
 682                 if (protocol != DNPROTO_NSP)
 683                         return -EPROTONOSUPPORT;
 684                 break;
 685         case SOCK_STREAM:
 686                 break;
 687         default:
 688                 return -ESOCKTNOSUPPORT;
 689         }
 690
 691
 692         if ((sk = dn_alloc_sock(net, sock, GFP_KERNEL, kern)) == NULL)
 693                 return -ENOBUFS;
 694
 695         sk->sk_protocol = protocol;
 696
 697         return 0;
 698 }
 699
 700
 701 static int
 702 dn_release(struct socket *sock)
 703 {
 704         struct sock *sk = sock->sk;
 705
 706         if (sk) {
 707                 sock_orphan(sk);
 708                 sock_hold(sk);
 709                 lock_sock(sk);
 710                 dn_destroy_sock(sk);
 711                 release_sock(sk);
 712                 sock_put(sk);
 713         }
 714
 715         return 0;
 716 }
 717
 718 static int dn_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 719 {
 720         struct sock *sk = sock->sk;
 721         struct dn_scp *scp = DN_SK(sk);
 722         struct sockaddr_dn *saddr = (struct sockaddr_dn *)uaddr;
 723         struct net_device *dev, *ldev;
 724         int rv;
 725
 726         if (addr_len != sizeof(struct sockaddr_dn))
 727                 return -EINVAL;
 728
 729         if (saddr->sdn_family != AF_DECnet)
 730                 return -EINVAL;
 731
 732         if (le16_to_cpu(saddr->sdn_nodeaddrl) && (le16_to_cpu(saddr->sdn_nodeaddrl) != 2))
 733                 return -EINVAL;
 734
 735         if (le16_to_cpu(saddr->sdn_objnamel) > DN_MAXOBJL)
 736                 return -EINVAL;
 737
 738         if (saddr->sdn_flags & ~SDF_WILD)
 739                 return -EINVAL;
 740
 741         if (!capable(CAP_NET_BIND_SERVICE) && (saddr->sdn_objnum ||
 742             (saddr->sdn_flags & SDF_WILD)))
 743                 return -EACCES;
 744
 745         if (!(saddr->sdn_flags & SDF_WILD)) {
 746                 if (le16_to_cpu(saddr->sdn_nodeaddrl)) {
 747                         rcu_read_lock();
 748                         ldev = NULL;
 749                         for_each_netdev_rcu(&init_net, dev) {
 750                                 if (!dev->dn_ptr)
 751                                         continue;
 752                                 if (dn_dev_islocal(dev, dn_saddr2dn(saddr))) {
 753                                         ldev = dev;
 754                                         break;
 755                                 }
 756                         }
 757                         rcu_read_unlock();
 758                         if (ldev == NULL)
 759                                 return -EADDRNOTAVAIL;
 760                 }
 761         }
 762
 763         rv = -EINVAL;
 764         lock_sock(sk);
 765         if (sock_flag(sk, SOCK_ZAPPED)) {
 766                 memcpy(&scp->addr, saddr, addr_len);
 767                 sock_reset_flag(sk, SOCK_ZAPPED);
 768
 769                 rv = dn_hash_sock(sk);
 770                 if (rv)
 771                         sock_set_flag(sk, SOCK_ZAPPED);
 772         }
 773         release_sock(sk);
 774
 775         return rv;
 776 }
 777
 778
 779 static int dn_auto_bind(struct socket *sock)
 780 {
 781         struct sock *sk = sock->sk;
 782         struct dn_scp *scp = DN_SK(sk);
 783         int rv;
 784
 785         sock_reset_flag(sk, SOCK_ZAPPED);
 786
 787         scp->addr.sdn_flags  = 0;
 788         scp->addr.sdn_objnum = 0;
 789
 790         /*
 791          * This stuff is to keep compatibility with Eduardo's
 792          * patch. I hope I can dispense with it shortly...
 793          */
 794         if ((scp->accessdata.acc_accl != 0) &&
 795                 (scp->accessdata.acc_accl <= 12)) {
 796
 797                 scp->addr.sdn_objnamel = cpu_to_le16(scp->accessdata.acc_accl);
 798                 memcpy(scp->addr.sdn_objname, scp->accessdata.acc_acc, le16_to_cpu(scp->addr.sdn_objnamel));
 799
 800                 scp->accessdata.acc_accl = 0;
 801                 memset(scp->accessdata.acc_acc, 0, 40);
 802         }
 803         /* End of compatibility stuff */
 804
 805         scp->addr.sdn_add.a_len = cpu_to_le16(2);
 806         rv = dn_dev_bind_default((__le16 *)scp->addr.sdn_add.a_addr);
 807         if (rv == 0) {
 808                 rv = dn_hash_sock(sk);
 809                 if (rv)
 810                         sock_set_flag(sk, SOCK_ZAPPED);
 811         }
 812
 813         return rv;
 814 }
 815
 816 static int dn_confirm_accept(struct sock *sk, long *timeo, gfp_t allocation)
 817 {
 818         struct dn_scp *scp = DN_SK(sk);
 819         DEFINE_WAIT(wait);
 820         int err;
 821
 822         if (scp->state != DN_CR)
 823                 return -EINVAL;
 824
 825         scp->state = DN_CC;
 826         scp->segsize_loc = dst_metric_advmss(__sk_dst_get(sk));
 827         dn_send_conn_conf(sk, allocation);
 828
 829         prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
 830         for(;;) {
 831                 release_sock(sk);
 832                 if (scp->state == DN_CC)
 833                         *timeo = schedule_timeout(*timeo);
 834                 lock_sock(sk);
 835                 err = 0;
 836                 if (scp->state == DN_RUN)
 837                         break;
 838                 err = sock_error(sk);
 839                 if (err)
 840                         break;
 841                 err = sock_intr_errno(*timeo);
 842                 if (signal_pending(current))
 843                         break;
 844                 err = -EAGAIN;
 845                 if (!*timeo)
 846                         break;
 847                 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
 848         }
 849         finish_wait(sk_sleep(sk), &wait);
 850         if (err == 0) {
 851                 sk->sk_socket->state = SS_CONNECTED;
 852         } else if (scp->state != DN_CC) {
 853                 sk->sk_socket->state = SS_UNCONNECTED;
 854         }
 855         return err;
 856 }
 857
 858 static int dn_wait_run(struct sock *sk, long *timeo)
 859 {
 860         struct dn_scp *scp = DN_SK(sk);
 861         DEFINE_WAIT(wait);
 862         int err = 0;
 863
 864         if (scp->state == DN_RUN)
 865                 goto out;
 866
 867         if (!*timeo)
 868                 return -EALREADY;
 869
 870         prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
 871         for(;;) {
 872                 release_sock(sk);
 873                 if (scp->state == DN_CI || scp->state == DN_CC)
 874                         *timeo = schedule_timeout(*timeo);
 875                 lock_sock(sk);
 876                 err = 0;
 877                 if (scp->state == DN_RUN)
 878                         break;
 879                 err = sock_error(sk);
 880                 if (err)
 881                         break;
 882                 err = sock_intr_errno(*timeo);
 883                 if (signal_pending(current))
 884                         break;
 885                 err = -ETIMEDOUT;
 886                 if (!*timeo)
 887                         break;
 888                 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
 889         }
 890         finish_wait(sk_sleep(sk), &wait);
 891 out:
 892         if (err == 0) {
 893                 sk->sk_socket->state = SS_CONNECTED;
 894         } else if (scp->state != DN_CI && scp->state != DN_CC) {
 895                 sk->sk_socket->state = SS_UNCONNECTED;
 896         }
 897         return err;
 898 }
 899
 900 static int __dn_connect(struct sock *sk, struct sockaddr_dn *addr, int addrlen, long *timeo, int flags)
 901 {
 902         struct socket *sock = sk->sk_socket;
 903         struct dn_scp *scp = DN_SK(sk);
 904         int err = -EISCONN;
 905         struct flowidn fld;
 906         struct dst_entry *dst;
 907
 908         if (sock->state == SS_CONNECTED)
 909                 goto out;
 910
 911         if (sock->state == SS_CONNECTING) {
 912                 err = 0;
 913                 if (scp->state == DN_RUN) {
 914                         sock->state = SS_CONNECTED;
 915                         goto out;
 916                 }
 917                 err = -ECONNREFUSED;
 918                 if (scp->state != DN_CI && scp->state != DN_CC) {
 919                         sock->state = SS_UNCONNECTED;
 920                         goto out;
 921                 }
 922                 return dn_wait_run(sk, timeo);
 923         }
 924
 925         err = -EINVAL;
 926         if (scp->state != DN_O)
 927                 goto out;
 928
 929         if (addr == NULL || addrlen != sizeof(struct sockaddr_dn))
 930                 goto out;
 931         if (addr->sdn_family != AF_DECnet)
 932                 goto out;
 933         if (addr->sdn_flags & SDF_WILD)
 934                 goto out;
 935
 936         if (sock_flag(sk, SOCK_ZAPPED)) {
 937                 err = dn_auto_bind(sk->sk_socket);
 938                 if (err)
 939                         goto out;
 940         }
 941
 942         memcpy(&scp->peer, addr, sizeof(struct sockaddr_dn));
 943
 944         err = -EHOSTUNREACH;
 945         memset(&fld, 0, sizeof(fld));
 946         fld.flowidn_oif = sk->sk_bound_dev_if;
 947         fld.daddr = dn_saddr2dn(&scp->peer);
 948         fld.saddr = dn_saddr2dn(&scp->addr);
 949         dn_sk_ports_copy(&fld, scp);
 950         fld.flowidn_proto = DNPROTO_NSP;
 951         if (dn_route_output_sock(&sk->sk_dst_cache, &fld, sk, flags) < 0)
 952                 goto out;
 953         dst = __sk_dst_get(sk);
 954         sk->sk_route_caps = dst->dev->features;
 955         sock->state = SS_CONNECTING;
 956         scp->state = DN_CI;
 957         scp->segsize_loc = dst_metric_advmss(dst);
 958
 959         dn_nsp_send_conninit(sk, NSP_CI);
 960         err = -EINPROGRESS;
 961         if (*timeo) {
 962                 err = dn_wait_run(sk, timeo);
 963         }
 964 out:
 965         return err;
 966 }
 967
 968 static int dn_connect(struct socket *sock, struct sockaddr *uaddr, int addrlen, int flags)
 969 {
 970         struct sockaddr_dn *addr = (struct sockaddr_dn *)uaddr;
 971         struct sock *sk = sock->sk;
 972         int err;
 973         long timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
 974
 975         lock_sock(sk);
 976         err = __dn_connect(sk, addr, addrlen, &timeo, 0);
 977         release_sock(sk);
 978
 979         return err;
 980 }
 981
 982 static inline int dn_check_state(struct sock *sk, struct sockaddr_dn *addr, int addrlen, long *timeo, int flags)
 983 {
 984         struct dn_scp *scp = DN_SK(sk);
 985
 986         switch (scp->state) {
 987         case DN_RUN:
 988                 return 0;
 989         case DN_CR:
 990                 return dn_confirm_accept(sk, timeo, sk->sk_allocation);
 991         case DN_CI:
 992         case DN_CC:
 993                 return dn_wait_run(sk, timeo);
 994         case DN_O:
 995                 return __dn_connect(sk, addr, addrlen, timeo, flags);
 996         }
 997
 998         return -EINVAL;
 999 }
1000
1001
1002 static void dn_access_copy(struct sk_buff *skb, struct accessdata_dn *acc)
1003 {
1004         unsigned char *ptr = skb->data;
1005
1006         acc->acc_userl = *ptr++;
1007         memcpy(&acc->acc_user, ptr, acc->acc_userl);
1008         ptr += acc->acc_userl;
1009
1010         acc->acc_passl = *ptr++;
1011         memcpy(&acc->acc_pass, ptr, acc->acc_passl);
1012         ptr += acc->acc_passl;
1013
1014         acc->acc_accl = *ptr++;
1015         memcpy(&acc->acc_acc, ptr, acc->acc_accl);
1016
1017         skb_pull(skb, acc->acc_accl + acc->acc_passl + acc->acc_userl + 3);
1018
1019 }
1020
1021 static void dn_user_copy(struct sk_buff *skb, struct optdata_dn *opt)
1022 {
1023         unsigned char *ptr = skb->data;
1024         u16 len = *ptr++; /* yes, it's 8bit on the wire */
1025
1026         BUG_ON(len > 16); /* we've checked the contents earlier */
1027         opt->opt_optl   = cpu_to_le16(len);
1028         opt->opt_status = 0;
1029         memcpy(opt->opt_data, ptr, len);
1030         skb_pull(skb, len + 1);
1031 }
1032
1033 static struct sk_buff *dn_wait_for_connect(struct sock *sk, long *timeo)
1034 {
1035         DEFINE_WAIT(wait);
1036         struct sk_buff *skb = NULL;
1037         int err = 0;
1038
1039         prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1040         for(;;) {
1041                 release_sock(sk);
1042                 skb = skb_dequeue(&sk->sk_receive_queue);
1043                 if (skb == NULL) {
1044                         *timeo = schedule_timeout(*timeo);
1045                         skb = skb_dequeue(&sk->sk_receive_queue);
1046                 }
1047                 lock_sock(sk);
1048                 if (skb != NULL)
1049                         break;
1050                 err = -EINVAL;
1051                 if (sk->sk_state != TCP_LISTEN)
1052                         break;
1053                 err = sock_intr_errno(*timeo);
1054                 if (signal_pending(current))
1055                         break;
1056                 err = -EAGAIN;
1057                 if (!*timeo)
1058                         break;
1059                 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1060         }
1061         finish_wait(sk_sleep(sk), &wait);
1062
1063         return skb == NULL ? ERR_PTR(err) : skb;
1064 }
1065
1066 static int dn_accept(struct socket *sock, struct socket *newsock, int flags,
1067                      bool kern)
1068 {
1069         struct sock *sk = sock->sk, *newsk;
1070         struct sk_buff *skb = NULL;
1071         struct dn_skb_cb *cb;
1072         unsigned char menuver;
1073         int err = 0;
1074         unsigned char type;
1075         long timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
1076         struct dst_entry *dst;
1077
1078         lock_sock(sk);
1079
1080         if (sk->sk_state != TCP_LISTEN || DN_SK(sk)->state != DN_O) {
1081                 release_sock(sk);
1082                 return -EINVAL;
1083         }
1084
1085         skb = skb_dequeue(&sk->sk_receive_queue);
1086         if (skb == NULL) {
1087                 skb = dn_wait_for_connect(sk, &timeo);
1088                 if (IS_ERR(skb)) {
1089                         release_sock(sk);
1090                         return PTR_ERR(skb);
1091                 }
1092         }
1093
1094         cb = DN_SKB_CB(skb);
1095         sk_acceptq_removed(sk);
1096         newsk = dn_alloc_sock(sock_net(sk), newsock, sk->sk_allocation, kern);
1097         if (newsk == NULL) {
1098                 release_sock(sk);
1099                 kfree_skb(skb);
1100                 return -ENOBUFS;
1101         }
1102         release_sock(sk);
1103
1104         dst = skb_dst(skb);
1105         sk_dst_set(newsk, dst);
1106         skb_dst_set(skb, NULL);
1107
1108         DN_SK(newsk)->state        = DN_CR;
1109         DN_SK(newsk)->addrrem      = cb->src_port;
1110         DN_SK(newsk)->services_rem = cb->services;
1111         DN_SK(newsk)->info_rem     = cb->info;
1112         DN_SK(newsk)->segsize_rem  = cb->segsize;
1113         DN_SK(newsk)->accept_mode  = DN_SK(sk)->accept_mode;
1114
1115         if (DN_SK(newsk)->segsize_rem < 230)
1116                 DN_SK(newsk)->segsize_rem = 230;
1117
1118         if ((DN_SK(newsk)->services_rem & NSP_FC_MASK) == NSP_FC_NONE)
1119                 DN_SK(newsk)->max_window = decnet_no_fc_max_cwnd;
1120
1121         newsk->sk_state  = TCP_LISTEN;
1122         memcpy(&(DN_SK(newsk)->addr), &(DN_SK(sk)->addr), sizeof(struct sockaddr_dn));
1123
1124         /*
1125          * If we are listening on a wild socket, we don't want
1126          * the newly created socket on the wrong hash queue.
1127          */
1128         DN_SK(newsk)->addr.sdn_flags &= ~SDF_WILD;
1129
1130         skb_pull(skb, dn_username2sockaddr(skb->data, skb->len, &(DN_SK(newsk)->addr), &type));
1131         skb_pull(skb, dn_username2sockaddr(skb->data, skb->len, &(DN_SK(newsk)->peer), &type));
1132         *(__le16 *)(DN_SK(newsk)->peer.sdn_add.a_addr) = cb->src;
1133         *(__le16 *)(DN_SK(newsk)->addr.sdn_add.a_addr) = cb->dst;
1134
1135         menuver = *skb->data;
1136         skb_pull(skb, 1);
1137
1138         if (menuver & DN_MENUVER_ACC)
1139                 dn_access_copy(skb, &(DN_SK(newsk)->accessdata));
1140
1141         if (menuver & DN_MENUVER_USR)
1142                 dn_user_copy(skb, &(DN_SK(newsk)->conndata_in));
1143
1144         if (menuver & DN_MENUVER_PRX)
1145                 DN_SK(newsk)->peer.sdn_flags |= SDF_PROXY;
1146
1147         if (menuver & DN_MENUVER_UIC)
1148                 DN_SK(newsk)->peer.sdn_flags |= SDF_UICPROXY;
1149
1150         kfree_skb(skb);
1151
1152         memcpy(&(DN_SK(newsk)->conndata_out), &(DN_SK(sk)->conndata_out),
1153                 sizeof(struct optdata_dn));
1154         memcpy(&(DN_SK(newsk)->discdata_out), &(DN_SK(sk)->discdata_out),
1155                 sizeof(struct optdata_dn));
1156
1157         lock_sock(newsk);
1158         err = dn_hash_sock(newsk);
1159         if (err == 0) {
1160                 sock_reset_flag(newsk, SOCK_ZAPPED);
1161                 dn_send_conn_ack(newsk);
1162
1163                 /*
1164                  * Here we use sk->sk_allocation since although the conn conf is
1165                  * for the newsk, the context is the old socket.
1166                  */
1167                 if (DN_SK(newsk)->accept_mode == ACC_IMMED)
1168                         err = dn_confirm_accept(newsk, &timeo,
1169                                                 sk->sk_allocation);
1170         }
1171         release_sock(newsk);
1172         return err;
1173 }
1174
1175
1176 static int dn_getname(struct socket *sock, struct sockaddr *uaddr,int peer)
1177 {
1178         struct sockaddr_dn *sa = (struct sockaddr_dn *)uaddr;
1179         struct sock *sk = sock->sk;
1180         struct dn_scp *scp = DN_SK(sk);
1181
1182         lock_sock(sk);
1183
1184         if (peer) {
1185                 if ((sock->state != SS_CONNECTED &&
1186                      sock->state != SS_CONNECTING) &&
1187                     scp->accept_mode == ACC_IMMED) {
1188                         release_sock(sk);
1189                         return -ENOTCONN;
1190                 }
1191
1192                 memcpy(sa, &scp->peer, sizeof(struct sockaddr_dn));
1193         } else {
1194                 memcpy(sa, &scp->addr, sizeof(struct sockaddr_dn));
1195         }
1196
1197         release_sock(sk);
1198
1199         return sizeof(struct sockaddr_dn);
1200 }
1201
1202
1203 static __poll_t dn_poll(struct file *file, struct socket *sock, poll_table  *wait)
1204 {
1205         struct sock *sk = sock->sk;
1206         struct dn_scp *scp = DN_SK(sk);
1207         __poll_t mask = datagram_poll(file, sock, wait);
1208
1209         if (!skb_queue_empty_lockless(&scp->other_receive_queue))
1210                 mask |= EPOLLRDBAND;
1211
1212         return mask;
1213 }
1214
1215 static int dn_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1216 {
1217         struct sock *sk = sock->sk;
1218         struct dn_scp *scp = DN_SK(sk);
1219         int err = -EOPNOTSUPP;
1220         long amount = 0;
1221         struct sk_buff *skb;
1222         int val;
1223
1224         switch(cmd)
1225         {
1226         case SIOCGIFADDR:
1227         case SIOCSIFADDR:
1228                 return dn_dev_ioctl(cmd, (void __user *)arg);
1229
1230         case SIOCATMARK:
1231                 lock_sock(sk);
1232                 val = !skb_queue_empty(&scp->other_receive_queue);
1233                 if (scp->state != DN_RUN)
1234                         val = -ENOTCONN;
1235                 release_sock(sk);
1236                 return val;
1237
1238         case TIOCOUTQ:
1239                 amount = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
1240                 if (amount < 0)
1241                         amount = 0;
1242                 err = put_user(amount, (int __user *)arg);
1243                 break;
1244
1245         case TIOCINQ:
1246                 lock_sock(sk);
1247                 skb = skb_peek(&scp->other_receive_queue);
1248                 if (skb) {
1249                         amount = skb->len;
1250                 } else {
1251                         skb_queue_walk(&sk->sk_receive_queue, skb)
1252                                 amount += skb->len;
1253                 }
1254                 release_sock(sk);
1255                 err = put_user(amount, (int __user *)arg);
1256                 break;
1257
1258         default:
1259                 err = -ENOIOCTLCMD;
1260                 break;
1261         }
1262
1263         return err;
1264 }
1265
1266 static int dn_listen(struct socket *sock, int backlog)
1267 {
1268         struct sock *sk = sock->sk;
1269         int err = -EINVAL;
1270
1271         lock_sock(sk);
1272
1273         if (sock_flag(sk, SOCK_ZAPPED))
1274                 goto out;
1275
1276         if ((DN_SK(sk)->state != DN_O) || (sk->sk_state == TCP_LISTEN))
1277                 goto out;
1278
1279         sk->sk_max_ack_backlog = backlog;
1280         sk->sk_ack_backlog     = 0;
1281         sk->sk_state           = TCP_LISTEN;
1282         err                 = 0;
1283         dn_rehash_sock(sk);
1284
1285 out:
1286         release_sock(sk);
1287
1288         return err;
1289 }
1290
1291
1292 static int dn_shutdown(struct socket *sock, int how)
1293 {
1294         struct sock *sk = sock->sk;
1295         struct dn_scp *scp = DN_SK(sk);
1296         int err = -ENOTCONN;
1297
1298         lock_sock(sk);
1299
1300         if (sock->state == SS_UNCONNECTED)
1301                 goto out;
1302
1303         err = 0;
1304         if (sock->state == SS_DISCONNECTING)
1305                 goto out;
1306
1307         err = -EINVAL;
1308         if (scp->state == DN_O)
1309                 goto out;
1310
1311         if (how != SHUT_RDWR)
1312                 goto out;
1313
1314         sk->sk_shutdown = SHUTDOWN_MASK;
1315         dn_destroy_sock(sk);
1316         err = 0;
1317
1318 out:
1319         release_sock(sk);
1320
1321         return err;
1322 }
1323
1324 static int dn_setsockopt(struct socket *sock, int level, int optname,
1325                 sockptr_t optval, unsigned int optlen)
1326 {
1327         struct sock *sk = sock->sk;
1328         int err;
1329
1330         lock_sock(sk);
1331         err = __dn_setsockopt(sock, level, optname, optval, optlen, 0);
1332         release_sock(sk);
1333 #ifdef CONFIG_NETFILTER
1334         /* we need to exclude all possible ENOPROTOOPTs except default case */
1335         if (err == -ENOPROTOOPT && optname != DSO_LINKINFO &&
1336             optname != DSO_STREAM && optname != DSO_SEQPACKET)
1337                 err = nf_setsockopt(sk, PF_DECnet, optname, optval, optlen);
1338 #endif
1339
1340         return err;
1341 }
1342
1343 static int __dn_setsockopt(struct socket *sock, int level, int optname,
1344                 sockptr_t optval, unsigned int optlen, int flags)
1345 {
1346         struct  sock *sk = sock->sk;
1347         struct dn_scp *scp = DN_SK(sk);
1348         long timeo;
1349         union {
1350                 struct optdata_dn opt;
1351                 struct accessdata_dn acc;
1352                 int mode;
1353                 unsigned long win;
1354                 int val;
1355                 unsigned char services;
1356                 unsigned char info;
1357         } u;
1358         int err;
1359
1360         if (optlen && sockptr_is_null(optval))
1361                 return -EINVAL;
1362
1363         if (optlen > sizeof(u))
1364                 return -EINVAL;
1365
1366         if (copy_from_sockptr(&u, optval, optlen))
1367                 return -EFAULT;
1368
1369         switch (optname) {
1370         case DSO_CONDATA:
1371                 if (sock->state == SS_CONNECTED)
1372                         return -EISCONN;
1373                 if ((scp->state != DN_O) && (scp->state != DN_CR))
1374                         return -EINVAL;
1375
1376                 if (optlen != sizeof(struct optdata_dn))
1377                         return -EINVAL;
1378
1379                 if (le16_to_cpu(u.opt.opt_optl) > 16)
1380                         return -EINVAL;
1381
1382                 memcpy(&scp->conndata_out, &u.opt, optlen);
1383                 break;
1384
1385         case DSO_DISDATA:
1386                 if (sock->state != SS_CONNECTED &&
1387                     scp->accept_mode == ACC_IMMED)
1388                         return -ENOTCONN;
1389
1390                 if (optlen != sizeof(struct optdata_dn))
1391                         return -EINVAL;
1392
1393                 if (le16_to_cpu(u.opt.opt_optl) > 16)
1394                         return -EINVAL;
1395
1396                 memcpy(&scp->discdata_out, &u.opt, optlen);
1397                 break;
1398
1399         case DSO_CONACCESS:
1400                 if (sock->state == SS_CONNECTED)
1401                         return -EISCONN;
1402                 if (scp->state != DN_O)
1403                         return -EINVAL;
1404
1405                 if (optlen != sizeof(struct accessdata_dn))
1406                         return -EINVAL;
1407
1408                 if ((u.acc.acc_accl > DN_MAXACCL) ||
1409                     (u.acc.acc_passl > DN_MAXACCL) ||
1410                     (u.acc.acc_userl > DN_MAXACCL))
1411                         return -EINVAL;
1412
1413                 memcpy(&scp->accessdata, &u.acc, optlen);
1414                 break;
1415
1416         case DSO_ACCEPTMODE:
1417                 if (sock->state == SS_CONNECTED)
1418                         return -EISCONN;
1419                 if (scp->state != DN_O)
1420                         return -EINVAL;
1421
1422                 if (optlen != sizeof(int))
1423                         return -EINVAL;
1424
1425                 if ((u.mode != ACC_IMMED) && (u.mode != ACC_DEFER))
1426                         return -EINVAL;
1427
1428                 scp->accept_mode = (unsigned char)u.mode;
1429                 break;
1430
1431         case DSO_CONACCEPT:
1432                 if (scp->state != DN_CR)
1433                         return -EINVAL;
1434                 timeo = sock_rcvtimeo(sk, 0);
1435                 err = dn_confirm_accept(sk, &timeo, sk->sk_allocation);
1436                 return err;
1437
1438         case DSO_CONREJECT:
1439                 if (scp->state != DN_CR)
1440                         return -EINVAL;
1441
1442                 scp->state = DN_DR;
1443                 sk->sk_shutdown = SHUTDOWN_MASK;
1444                 dn_nsp_send_disc(sk, 0x38, 0, sk->sk_allocation);
1445                 break;
1446
1447         case DSO_MAXWINDOW:
1448                 if (optlen != sizeof(unsigned long))
1449                         return -EINVAL;
1450                 if (u.win > NSP_MAX_WINDOW)
1451                         u.win = NSP_MAX_WINDOW;
1452                 if (u.win == 0)
1453                         return -EINVAL;
1454                 scp->max_window = u.win;
1455                 if (scp->snd_window > u.win)
1456                         scp->snd_window = u.win;
1457                 break;
1458
1459         case DSO_NODELAY:
1460                 if (optlen != sizeof(int))
1461                         return -EINVAL;
1462                 if (scp->nonagle == TCP_NAGLE_CORK)
1463                         return -EINVAL;
1464                 scp->nonagle = (u.val == 0) ? 0 : TCP_NAGLE_OFF;
1465                 /* if (scp->nonagle == 1) { Push pending frames } */
1466                 break;
1467
1468         case DSO_CORK:
1469                 if (optlen != sizeof(int))
1470                         return -EINVAL;
1471                 if (scp->nonagle == TCP_NAGLE_OFF)
1472                         return -EINVAL;
1473                 scp->nonagle = (u.val == 0) ? 0 : TCP_NAGLE_CORK;
1474                 /* if (scp->nonagle == 0) { Push pending frames } */
1475                 break;
1476
1477         case DSO_SERVICES:
1478                 if (optlen != sizeof(unsigned char))
1479                         return -EINVAL;
1480                 if ((u.services & ~NSP_FC_MASK) != 0x01)
1481                         return -EINVAL;
1482                 if ((u.services & NSP_FC_MASK) == NSP_FC_MASK)
1483                         return -EINVAL;
1484                 scp->services_loc = u.services;
1485                 break;
1486
1487         case DSO_INFO:
1488                 if (optlen != sizeof(unsigned char))
1489                         return -EINVAL;
1490                 if (u.info & 0xfc)
1491                         return -EINVAL;
1492                 scp->info_loc = u.info;
1493                 break;
1494
1495         case DSO_LINKINFO:
1496         case DSO_STREAM:
1497         case DSO_SEQPACKET:
1498         default:
1499                 return -ENOPROTOOPT;
1500         }
1501
1502         return 0;
1503 }
1504
1505 static int dn_getsockopt(struct socket *sock, int level, int optname, char __user *optval, int __user *optlen)
1506 {
1507         struct sock *sk = sock->sk;
1508         int err;
1509
1510         lock_sock(sk);
1511         err = __dn_getsockopt(sock, level, optname, optval, optlen, 0);
1512         release_sock(sk);
1513 #ifdef CONFIG_NETFILTER
1514         if (err == -ENOPROTOOPT && optname != DSO_STREAM &&
1515             optname != DSO_SEQPACKET && optname != DSO_CONACCEPT &&
1516             optname != DSO_CONREJECT) {
1517                 int len;
1518
1519                 if (get_user(len, optlen))
1520                         return -EFAULT;
1521
1522                 err = nf_getsockopt(sk, PF_DECnet, optname, optval, &len);
1523                 if (err >= 0)
1524                         err = put_user(len, optlen);
1525         }
1526 #endif
1527
1528         return err;
1529 }
1530
1531 static int __dn_getsockopt(struct socket *sock, int level,int optname, char __user *optval,int __user *optlen, int flags)
1532 {
1533         struct  sock *sk = sock->sk;
1534         struct dn_scp *scp = DN_SK(sk);
1535         struct linkinfo_dn link;
1536         unsigned int r_len;
1537         void *r_data = NULL;
1538         unsigned int val;
1539
1540         if(get_user(r_len , optlen))
1541                 return -EFAULT;
1542
1543         switch (optname) {
1544         case DSO_CONDATA:
1545                 if (r_len > sizeof(struct optdata_dn))
1546                         r_len = sizeof(struct optdata_dn);
1547                 r_data = &scp->conndata_in;
1548                 break;
1549
1550         case DSO_DISDATA:
1551                 if (r_len > sizeof(struct optdata_dn))
1552                         r_len = sizeof(struct optdata_dn);
1553                 r_data = &scp->discdata_in;
1554                 break;
1555
1556         case DSO_CONACCESS:
1557                 if (r_len > sizeof(struct accessdata_dn))
1558                         r_len = sizeof(struct accessdata_dn);
1559                 r_data = &scp->accessdata;
1560                 break;
1561
1562         case DSO_ACCEPTMODE:
1563                 if (r_len > sizeof(unsigned char))
1564                         r_len = sizeof(unsigned char);
1565                 r_data = &scp->accept_mode;
1566                 break;
1567
1568         case DSO_LINKINFO:
1569                 if (r_len > sizeof(struct linkinfo_dn))
1570                         r_len = sizeof(struct linkinfo_dn);
1571
1572                 memset(&link, 0, sizeof(link));
1573
1574                 switch (sock->state) {
1575                 case SS_CONNECTING:
1576                         link.idn_linkstate = LL_CONNECTING;
1577                         break;
1578                 case SS_DISCONNECTING:
1579                         link.idn_linkstate = LL_DISCONNECTING;
1580                         break;
1581                 case SS_CONNECTED:
1582                         link.idn_linkstate = LL_RUNNING;
1583                         break;
1584                 default:
1585                         link.idn_linkstate = LL_INACTIVE;
1586                 }
1587
1588                 link.idn_segsize = scp->segsize_rem;
1589                 r_data = &link;
1590                 break;
1591
1592         case DSO_MAXWINDOW:
1593                 if (r_len > sizeof(unsigned long))
1594                         r_len = sizeof(unsigned long);
1595                 r_data = &scp->max_window;
1596                 break;
1597
1598         case DSO_NODELAY:
1599                 if (r_len > sizeof(int))
1600                         r_len = sizeof(int);
1601                 val = (scp->nonagle == TCP_NAGLE_OFF);
1602                 r_data = &val;
1603                 break;
1604
1605         case DSO_CORK:
1606                 if (r_len > sizeof(int))
1607                         r_len = sizeof(int);
1608                 val = (scp->nonagle == TCP_NAGLE_CORK);
1609                 r_data = &val;
1610                 break;
1611
1612         case DSO_SERVICES:
1613                 if (r_len > sizeof(unsigned char))
1614                         r_len = sizeof(unsigned char);
1615                 r_data = &scp->services_rem;
1616                 break;
1617
1618         case DSO_INFO:
1619                 if (r_len > sizeof(unsigned char))
1620                         r_len = sizeof(unsigned char);
1621                 r_data = &scp->info_rem;
1622                 break;
1623
1624         case DSO_STREAM:
1625         case DSO_SEQPACKET:
1626         case DSO_CONACCEPT:
1627         case DSO_CONREJECT:
1628         default:
1629                 return -ENOPROTOOPT;
1630         }
1631
1632         if (r_data) {
1633                 if (copy_to_user(optval, r_data, r_len))
1634                         return -EFAULT;
1635                 if (put_user(r_len, optlen))
1636                         return -EFAULT;
1637         }
1638
1639         return 0;
1640 }
1641
1642
1643 static int dn_data_ready(struct sock *sk, struct sk_buff_head *q, int flags, int target)
1644 {
1645         struct sk_buff *skb;
1646         int len = 0;
1647
1648         if (flags & MSG_OOB)
1649                 return !skb_queue_empty(q) ? 1 : 0;
1650
1651         skb_queue_walk(q, skb) {
1652                 struct dn_skb_cb *cb = DN_SKB_CB(skb);
1653                 len += skb->len;
1654
1655                 if (cb->nsp_flags & 0x40) {
1656                         /* SOCK_SEQPACKET reads to EOM */
1657                         if (sk->sk_type == SOCK_SEQPACKET)
1658                                 return 1;
1659                         /* so does SOCK_STREAM unless WAITALL is specified */
1660                         if (!(flags & MSG_WAITALL))
1661                                 return 1;
1662                 }
1663
1664                 /* minimum data length for read exceeded */
1665                 if (len >= target)
1666                         return 1;
1667         }
1668
1669         return 0;
1670 }
1671
1672
1673 static int dn_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1674                       int flags)
1675 {
1676         struct sock *sk = sock->sk;
1677         struct dn_scp *scp = DN_SK(sk);
1678         struct sk_buff_head *queue = &sk->sk_receive_queue;
1679         size_t target = size > 1 ? 1 : 0;
1680         size_t copied = 0;
1681         int rv = 0;
1682         struct sk_buff *skb, *n;
1683         struct dn_skb_cb *cb = NULL;
1684         unsigned char eor = 0;
1685         long timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
1686
1687         lock_sock(sk);
1688
1689         if (sock_flag(sk, SOCK_ZAPPED)) {
1690                 rv = -EADDRNOTAVAIL;
1691                 goto out;
1692         }
1693
1694         if (sk->sk_shutdown & RCV_SHUTDOWN) {
1695                 rv = 0;
1696                 goto out;
1697         }
1698
1699         rv = dn_check_state(sk, NULL, 0, &timeo, flags);
1700         if (rv)
1701                 goto out;
1702
1703         if (flags & ~(MSG_CMSG_COMPAT|MSG_PEEK|MSG_OOB|MSG_WAITALL|MSG_DONTWAIT|MSG_NOSIGNAL)) {
1704                 rv = -EOPNOTSUPP;
1705                 goto out;
1706         }
1707
1708         if (flags & MSG_OOB)
1709                 queue = &scp->other_receive_queue;
1710
1711         if (flags & MSG_WAITALL)
1712                 target = size;
1713
1714
1715         /*
1716          * See if there is data ready to read, sleep if there isn't
1717          */
1718         for(;;) {
1719                 DEFINE_WAIT_FUNC(wait, woken_wake_function);
1720
1721                 if (sk->sk_err)
1722                         goto out;
1723
1724                 if (!skb_queue_empty(&scp->other_receive_queue)) {
1725                         if (!(flags & MSG_OOB)) {
1726                                 msg->msg_flags |= MSG_OOB;
1727                                 if (!scp->other_report) {
1728                                         scp->other_report = 1;
1729                                         goto out;
1730                                 }
1731                         }
1732                 }
1733
1734                 if (scp->state != DN_RUN)
1735                         goto out;
1736
1737                 if (signal_pending(current)) {
1738                         rv = sock_intr_errno(timeo);
1739                         goto out;
1740                 }
1741
1742                 if (dn_data_ready(sk, queue, flags, target))
1743                         break;
1744
1745                 if (flags & MSG_DONTWAIT) {
1746                         rv = -EWOULDBLOCK;
1747                         goto out;
1748                 }
1749
1750                 add_wait_queue(sk_sleep(sk), &wait);
1751                 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
1752                 sk_wait_event(sk, &timeo, dn_data_ready(sk, queue, flags, target), &wait);
1753                 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
1754                 remove_wait_queue(sk_sleep(sk), &wait);
1755         }
1756
1757         skb_queue_walk_safe(queue, skb, n) {
1758                 unsigned int chunk = skb->len;
1759                 cb = DN_SKB_CB(skb);
1760
1761                 if ((chunk + copied) > size)
1762                         chunk = size - copied;
1763
1764                 if (memcpy_to_msg(msg, skb->data, chunk)) {
1765                         rv = -EFAULT;
1766                         break;
1767                 }
1768                 copied += chunk;
1769
1770                 if (!(flags & MSG_PEEK))
1771                         skb_pull(skb, chunk);
1772
1773                 eor = cb->nsp_flags & 0x40;
1774
1775                 if (skb->len == 0) {
1776                         skb_unlink(skb, queue);
1777                         kfree_skb(skb);
1778                         /*
1779                          * N.B. Don't refer to skb or cb after this point
1780                          * in loop.
1781                          */
1782                         if ((scp->flowloc_sw == DN_DONTSEND) && !dn_congested(sk)) {
1783                                 scp->flowloc_sw = DN_SEND;
1784                                 dn_nsp_send_link(sk, DN_SEND, 0);
1785                         }
1786                 }
1787
1788                 if (eor) {
1789                         if (sk->sk_type == SOCK_SEQPACKET)
1790                                 break;
1791                         if (!(flags & MSG_WAITALL))
1792                                 break;
1793                 }
1794
1795                 if (flags & MSG_OOB)
1796                         break;
1797
1798                 if (copied >= target)
1799                         break;
1800         }
1801
1802         rv = copied;
1803
1804
1805         if (eor && (sk->sk_type == SOCK_SEQPACKET))
1806                 msg->msg_flags |= MSG_EOR;
1807
1808 out:
1809         if (rv == 0)
1810                 rv = (flags & MSG_PEEK) ? -sk->sk_err : sock_error(sk);
1811
1812         if ((rv >= 0) && msg->msg_name) {
1813                 __sockaddr_check_size(sizeof(struct sockaddr_dn));
1814                 memcpy(msg->msg_name, &scp->peer, sizeof(struct sockaddr_dn));
1815                 msg->msg_namelen = sizeof(struct sockaddr_dn);
1816         }
1817
1818         release_sock(sk);
1819
1820         return rv;
1821 }
1822
1823
1824 static inline int dn_queue_too_long(struct dn_scp *scp, struct sk_buff_head *queue, int flags)
1825 {
1826         unsigned char fctype = scp->services_rem & NSP_FC_MASK;
1827         if (skb_queue_len(queue) >= scp->snd_window)
1828                 return 1;
1829         if (fctype != NSP_FC_NONE) {
1830                 if (flags & MSG_OOB) {
1831                         if (scp->flowrem_oth == 0)
1832                                 return 1;
1833                 } else {
1834                         if (scp->flowrem_dat == 0)
1835                                 return 1;
1836                 }
1837         }
1838         return 0;
1839 }
1840
1841 /*
1842  * The DECnet spec requires that the "routing layer" accepts packets which
1843  * are at least 230 bytes in size. This excludes any headers which the NSP
1844  * layer might add, so we always assume that we'll be using the maximal
1845  * length header on data packets. The variation in length is due to the
1846  * inclusion (or not) of the two 16 bit acknowledgement fields so it doesn't
1847  * make much practical difference.
1848  */
1849 unsigned int dn_mss_from_pmtu(struct net_device *dev, int mtu)
1850 {
1851         unsigned int mss = 230 - DN_MAX_NSP_DATA_HEADER;
1852         if (dev) {
1853                 struct dn_dev *dn_db = rcu_dereference_raw(dev->dn_ptr);
1854                 mtu -= LL_RESERVED_SPACE(dev);
1855                 if (dn_db->use_long)
1856                         mtu -= 21;
1857                 else
1858                         mtu -= 6;
1859                 mtu -= DN_MAX_NSP_DATA_HEADER;
1860         } else {
1861                 /*
1862                  * 21 = long header, 16 = guess at MAC header length
1863                  */
1864                 mtu -= (21 + DN_MAX_NSP_DATA_HEADER + 16);
1865         }
1866         if (mtu > mss)
1867                 mss = mtu;
1868         return mss;
1869 }
1870
1871 static inline unsigned int dn_current_mss(struct sock *sk, int flags)
1872 {
1873         struct dst_entry *dst = __sk_dst_get(sk);
1874         struct dn_scp *scp = DN_SK(sk);
1875         int mss_now = min_t(int, scp->segsize_loc, scp->segsize_rem);
1876
1877         /* Other data messages are limited to 16 bytes per packet */
1878         if (flags & MSG_OOB)
1879                 return 16;
1880
1881         /* This works out the maximum size of segment we can send out */
1882         if (dst) {
1883                 u32 mtu = dst_mtu(dst);
1884                 mss_now = min_t(int, dn_mss_from_pmtu(dst->dev, mtu), mss_now);
1885         }
1886
1887         return mss_now;
1888 }
1889
1890 /*
1891  * N.B. We get the timeout wrong here, but then we always did get it
1892  * wrong before and this is another step along the road to correcting
1893  * it. It ought to get updated each time we pass through the routine,
1894  * but in practise it probably doesn't matter too much for now.
1895  */
1896 static inline struct sk_buff *dn_alloc_send_pskb(struct sock *sk,
1897                               unsigned long datalen, int noblock,
1898                               int *errcode)
1899 {
1900         struct sk_buff *skb = sock_alloc_send_skb(sk, datalen,
1901                                                    noblock, errcode);
1902         if (skb) {
1903                 skb->protocol = htons(ETH_P_DNA_RT);
1904                 skb->pkt_type = PACKET_OUTGOING;
1905         }
1906         return skb;
1907 }
1908
1909 static int dn_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
1910 {
1911         struct sock *sk = sock->sk;
1912         struct dn_scp *scp = DN_SK(sk);
1913         size_t mss;
1914         struct sk_buff_head *queue = &scp->data_xmit_queue;
1915         int flags = msg->msg_flags;
1916         int err = 0;
1917         size_t sent = 0;
1918         int addr_len = msg->msg_namelen;
1919         DECLARE_SOCKADDR(struct sockaddr_dn *, addr, msg->msg_name);
1920         struct sk_buff *skb = NULL;
1921         struct dn_skb_cb *cb;
1922         size_t len;
1923         unsigned char fctype;
1924         long timeo;
1925
1926         if (flags & ~(MSG_TRYHARD|MSG_OOB|MSG_DONTWAIT|MSG_EOR|MSG_NOSIGNAL|MSG_MORE|MSG_CMSG_COMPAT))
1927                 return -EOPNOTSUPP;
1928
1929         if (addr_len && (addr_len != sizeof(struct sockaddr_dn)))
1930                 return -EINVAL;
1931
1932         lock_sock(sk);
1933         timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
1934         /*
1935          * The only difference between stream sockets and sequenced packet
1936          * sockets is that the stream sockets always behave as if MSG_EOR
1937          * has been set.
1938          */
1939         if (sock->type == SOCK_STREAM) {
1940                 if (flags & MSG_EOR) {
1941                         err = -EINVAL;
1942                         goto out;
1943                 }
1944                 flags |= MSG_EOR;
1945         }
1946
1947
1948         err = dn_check_state(sk, addr, addr_len, &timeo, flags);
1949         if (err)
1950                 goto out_err;
1951
1952         if (sk->sk_shutdown & SEND_SHUTDOWN) {
1953                 err = -EPIPE;
1954                 if (!(flags & MSG_NOSIGNAL))
1955                         send_sig(SIGPIPE, current, 0);
1956                 goto out_err;
1957         }
1958
1959         if ((flags & MSG_TRYHARD) && sk->sk_dst_cache)
1960                 dst_negative_advice(sk);
1961
1962         mss = scp->segsize_rem;
1963         fctype = scp->services_rem & NSP_FC_MASK;
1964
1965         mss = dn_current_mss(sk, flags);
1966
1967         if (flags & MSG_OOB) {
1968                 queue = &scp->other_xmit_queue;
1969                 if (size > mss) {
1970                         err = -EMSGSIZE;
1971                         goto out;
1972                 }
1973         }
1974
1975         scp->persist_fxn = dn_nsp_xmit_timeout;
1976
1977         while(sent < size) {
1978                 err = sock_error(sk);
1979                 if (err)
1980                         goto out;
1981
1982                 if (signal_pending(current)) {
1983                         err = sock_intr_errno(timeo);
1984                         goto out;
1985                 }
1986
1987                 /*
1988                  * Calculate size that we wish to send.
1989                  */
1990                 len = size - sent;
1991
1992                 if (len > mss)
1993                         len = mss;
1994
1995                 /*
1996                  * Wait for queue size to go down below the window
1997                  * size.
1998                  */
1999                 if (dn_queue_too_long(scp, queue, flags)) {
2000                         DEFINE_WAIT_FUNC(wait, woken_wake_function);
2001
2002                         if (flags & MSG_DONTWAIT) {
2003                                 err = -EWOULDBLOCK;
2004                                 goto out;
2005                         }
2006
2007                         add_wait_queue(sk_sleep(sk), &wait);
2008                         sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2009                         sk_wait_event(sk, &timeo,
2010                                       !dn_queue_too_long(scp, queue, flags), &wait);
2011                         sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2012                         remove_wait_queue(sk_sleep(sk), &wait);
2013                         continue;
2014                 }
2015
2016                 /*
2017                  * Get a suitably sized skb.
2018                  * 64 is a bit of a hack really, but its larger than any
2019                  * link-layer headers and has served us well as a good
2020                  * guess as to their real length.
2021                  */
2022                 skb = dn_alloc_send_pskb(sk, len + 64 + DN_MAX_NSP_DATA_HEADER,
2023                                          flags & MSG_DONTWAIT, &err);
2024
2025                 if (err)
2026                         break;
2027
2028                 if (!skb)
2029                         continue;
2030
2031                 cb = DN_SKB_CB(skb);
2032
2033                 skb_reserve(skb, 64 + DN_MAX_NSP_DATA_HEADER);
2034
2035                 if (memcpy_from_msg(skb_put(skb, len), msg, len)) {
2036                         err = -EFAULT;
2037                         goto out;
2038                 }
2039
2040                 if (flags & MSG_OOB) {
2041                         cb->nsp_flags = 0x30;
2042                         if (fctype != NSP_FC_NONE)
2043                                 scp->flowrem_oth--;
2044                 } else {
2045                         cb->nsp_flags = 0x00;
2046                         if (scp->seg_total == 0)
2047                                 cb->nsp_flags |= 0x20;
2048
2049                         scp->seg_total += len;
2050
2051                         if (((sent + len) == size) && (flags & MSG_EOR)) {
2052                                 cb->nsp_flags |= 0x40;
2053                                 scp->seg_total = 0;
2054                                 if (fctype == NSP_FC_SCMC)
2055                                         scp->flowrem_dat--;
2056                         }
2057                         if (fctype == NSP_FC_SRC)
2058                                 scp->flowrem_dat--;
2059                 }
2060
2061                 sent += len;
2062                 dn_nsp_queue_xmit(sk, skb, sk->sk_allocation, flags & MSG_OOB);
2063                 skb = NULL;
2064
2065                 scp->persist = dn_nsp_persist(sk);
2066
2067         }
2068 out:
2069
2070         kfree_skb(skb);
2071
2072         release_sock(sk);
2073
2074         return sent ? sent : err;
2075
2076 out_err:
2077         err = sk_stream_error(sk, flags, err);
2078         release_sock(sk);
2079         return err;
2080 }
2081
2082 static int dn_device_event(struct notifier_block *this, unsigned long event,
2083                            void *ptr)
2084 {
2085         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
2086
2087         if (!net_eq(dev_net(dev), &init_net))
2088                 return NOTIFY_DONE;
2089
2090         switch (event) {
2091         case NETDEV_UP:
2092                 dn_dev_up(dev);
2093                 break;
2094         case NETDEV_DOWN:
2095                 dn_dev_down(dev);
2096                 break;
2097         default:
2098                 break;
2099         }
2100
2101         return NOTIFY_DONE;
2102 }
2103
2104 static struct notifier_block dn_dev_notifier = {
2105         .notifier_call = dn_device_event,
2106 };
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         while (!n) {
2141                 if (++state->bucket >= DN_SK_HASH_SIZE)
2142                         break;
2143                 n = sk_head(&dn_sk_hash[state->bucket]);
2144         }
2145         return n;
2146 }
2147
2148 static struct sock *socket_get_idx(struct seq_file *seq, loff_t *pos)
2149 {
2150         struct sock *sk = dn_socket_get_first(seq);
2151
2152         if (sk) {
2153                 while(*pos && (sk = dn_socket_get_next(seq, sk)))
2154                         --*pos;
2155         }
2156         return *pos ? NULL : sk;
2157 }
2158
2159 static void *dn_socket_get_idx(struct seq_file *seq, loff_t pos)
2160 {
2161         void *rc;
2162         read_lock_bh(&dn_hash_lock);
2163         rc = socket_get_idx(seq, &pos);
2164         if (!rc) {
2165                 read_unlock_bh(&dn_hash_lock);
2166         }
2167         return rc;
2168 }
2169
2170 static void *dn_socket_seq_start(struct seq_file *seq, loff_t *pos)
2171 {
2172         return *pos ? dn_socket_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2173 }
2174
2175 static void *dn_socket_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2176 {
2177         void *rc;
2178
2179         if (v == SEQ_START_TOKEN) {
2180                 rc = dn_socket_get_idx(seq, 0);
2181                 goto out;
2182         }
2183
2184         rc = dn_socket_get_next(seq, v);
2185         if (rc)
2186                 goto out;
2187         read_unlock_bh(&dn_hash_lock);
2188 out:
2189         ++*pos;
2190         return rc;
2191 }
2192
2193 static void dn_socket_seq_stop(struct seq_file *seq, void *v)
2194 {
2195         if (v && v != SEQ_START_TOKEN)
2196                 read_unlock_bh(&dn_hash_lock);
2197 }
2198
2199 #define IS_NOT_PRINTABLE(x) ((x) < 32 || (x) > 126)
2200
2201 static void dn_printable_object(struct sockaddr_dn *dn, unsigned char *buf)
2202 {
2203         int i;
2204
2205         switch (le16_to_cpu(dn->sdn_objnamel)) {
2206         case 0:
2207                 sprintf(buf, "%d", dn->sdn_objnum);
2208                 break;
2209         default:
2210                 for (i = 0; i < le16_to_cpu(dn->sdn_objnamel); i++) {
2211                         buf[i] = dn->sdn_objname[i];
2212                         if (IS_NOT_PRINTABLE(buf[i]))
2213                                 buf[i] = '.';
2214                 }
2215                 buf[i] = 0;
2216         }
2217 }
2218
2219 static char *dn_state2asc(unsigned char state)
2220 {
2221         switch (state) {
2222         case DN_O:
2223                 return "OPEN";
2224         case DN_CR:
2225                 return "  CR";
2226         case DN_DR:
2227                 return "  DR";
2228         case DN_DRC:
2229                 return " DRC";
2230         case DN_CC:
2231                 return "  CC";
2232         case DN_CI:
2233                 return "  CI";
2234         case DN_NR:
2235                 return "  NR";
2236         case DN_NC:
2237                 return "  NC";
2238         case DN_CD:
2239                 return "  CD";
2240         case DN_RJ:
2241                 return "  RJ";
2242         case DN_RUN:
2243                 return " RUN";
2244         case DN_DI:
2245                 return "  DI";
2246         case DN_DIC:
2247                 return " DIC";
2248         case DN_DN:
2249                 return "  DN";
2250         case DN_CL:
2251                 return "  CL";
2252         case DN_CN:
2253                 return "  CN";
2254         }
2255
2256         return "????";
2257 }
2258
2259 static inline void dn_socket_format_entry(struct seq_file *seq, struct sock *sk)
2260 {
2261         struct dn_scp *scp = DN_SK(sk);
2262         char buf1[DN_ASCBUF_LEN];
2263         char buf2[DN_ASCBUF_LEN];
2264         char local_object[DN_MAXOBJL+3];
2265         char remote_object[DN_MAXOBJL+3];
2266
2267         dn_printable_object(&scp->addr, local_object);
2268         dn_printable_object(&scp->peer, remote_object);
2269
2270         seq_printf(seq,
2271                    "%6s/%04X %04d:%04d %04d:%04d %01d %-16s "
2272                    "%6s/%04X %04d:%04d %04d:%04d %01d %-16s %4s %s\n",
2273                    dn_addr2asc(le16_to_cpu(dn_saddr2dn(&scp->addr)), buf1),
2274                    scp->addrloc,
2275                    scp->numdat,
2276                    scp->numoth,
2277                    scp->ackxmt_dat,
2278                    scp->ackxmt_oth,
2279                    scp->flowloc_sw,
2280                    local_object,
2281                    dn_addr2asc(le16_to_cpu(dn_saddr2dn(&scp->peer)), buf2),
2282                    scp->addrrem,
2283                    scp->numdat_rcv,
2284                    scp->numoth_rcv,
2285                    scp->ackrcv_dat,
2286                    scp->ackrcv_oth,
2287                    scp->flowrem_sw,
2288                    remote_object,
2289                    dn_state2asc(scp->state),
2290                    ((scp->accept_mode == ACC_IMMED) ? "IMMED" : "DEFER"));
2291 }
2292
2293 static int dn_socket_seq_show(struct seq_file *seq, void *v)
2294 {
2295         if (v == SEQ_START_TOKEN) {
2296                 seq_puts(seq, "Local                                              Remote\n");
2297         } else {
2298                 dn_socket_format_entry(seq, v);
2299         }
2300         return 0;
2301 }
2302
2303 static const struct seq_operations dn_socket_seq_ops = {
2304         .start  = dn_socket_seq_start,
2305         .next   = dn_socket_seq_next,
2306         .stop   = dn_socket_seq_stop,
2307         .show   = dn_socket_seq_show,
2308 };
2309 #endif
2310
2311 static const struct net_proto_family    dn_family_ops = {
2312         .family =       AF_DECnet,
2313         .create =       dn_create,
2314         .owner  =       THIS_MODULE,
2315 };
2316
2317 static const struct proto_ops dn_proto_ops = {
2318         .family =       AF_DECnet,
2319         .owner =        THIS_MODULE,
2320         .release =      dn_release,
2321         .bind =         dn_bind,
2322         .connect =      dn_connect,
2323         .socketpair =   sock_no_socketpair,
2324         .accept =       dn_accept,
2325         .getname =      dn_getname,
2326         .poll =         dn_poll,
2327         .ioctl =        dn_ioctl,
2328         .listen =       dn_listen,
2329         .shutdown =     dn_shutdown,
2330         .setsockopt =   dn_setsockopt,
2331         .getsockopt =   dn_getsockopt,
2332         .sendmsg =      dn_sendmsg,
2333         .recvmsg =      dn_recvmsg,
2334         .mmap =         sock_no_mmap,
2335         .sendpage =     sock_no_sendpage,
2336 };
2337
2338 MODULE_DESCRIPTION("The Linux DECnet Network Protocol");
2339 MODULE_AUTHOR("Linux DECnet Project Team");
2340 MODULE_LICENSE("GPL");
2341 MODULE_ALIAS_NETPROTO(PF_DECnet);
2342
2343 static const char banner[] __initconst = KERN_INFO
2344 "NET4: DECnet for Linux: V.2.5.68s (C) 1995-2003 Linux DECnet Project Team\n";
2345
2346 static int __init decnet_init(void)
2347 {
2348         int rc;
2349
2350         printk(banner);
2351
2352         rc = proto_register(&dn_proto, 1);
2353         if (rc != 0)
2354                 goto out;
2355
2356         dn_neigh_init();
2357         dn_dev_init();
2358         dn_route_init();
2359         dn_fib_init();
2360
2361         sock_register(&dn_family_ops);
2362         dev_add_pack(&dn_dix_packet_type);
2363         register_netdevice_notifier(&dn_dev_notifier);
2364
2365         proc_create_seq_private("decnet", 0444, init_net.proc_net,
2366                         &dn_socket_seq_ops, sizeof(struct dn_iter_state),
2367                         NULL);
2368         dn_register_sysctl();
2369 out:
2370         return rc;
2371
2372 }
2373 module_init(decnet_init);
2374
2375 /*
2376  * Prevent DECnet module unloading until its fixed properly.
2377  * Requires an audit of the code to check for memory leaks and
2378  * initialisation problems etc.
2379  */
2380 #if 0
2381 static void __exit decnet_exit(void)
2382 {
2383         sock_unregister(AF_DECnet);
2384         rtnl_unregister_all(PF_DECnet);
2385         dev_remove_pack(&dn_dix_packet_type);
2386
2387         dn_unregister_sysctl();
2388
2389         unregister_netdevice_notifier(&dn_dev_notifier);
2390
2391         dn_route_cleanup();
2392         dn_dev_cleanup();
2393         dn_neigh_cleanup();
2394         dn_fib_cleanup();
2395
2396         remove_proc_entry("decnet", init_net.proc_net);
2397
2398         proto_unregister(&dn_proto);
2399
2400         rcu_barrier(); /* Wait for completion of call_rcu()'s */
2401 }
2402 module_exit(decnet_exit);
2403 #endif