net/iucv/af_iucv.c

   1 /*
   2  *  linux/net/iucv/af_iucv.c
   3  *
   4  *  IUCV protocol stack for Linux on zSeries
   5  *
   6  *  Copyright 2006 IBM Corporation
   7  *
   8  *  Author(s):  Jennifer Hunt <jenhunt@us.ibm.com>
   9  */
  10
  11 #define KMSG_COMPONENT "af_iucv"
  12 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  13
  14 #include <linux/module.h>
  15 #include <linux/types.h>
  16 #include <linux/list.h>
  17 #include <linux/errno.h>
  18 #include <linux/kernel.h>
  19 #include <linux/sched.h>
  20 #include <linux/slab.h>
  21 #include <linux/skbuff.h>
  22 #include <linux/init.h>
  23 #include <linux/poll.h>
  24 #include <net/sock.h>
  25 #include <asm/ebcdic.h>
  26 #include <asm/cpcmd.h>
  27 #include <linux/kmod.h>
  28
  29 #include <net/iucv/iucv.h>
  30 #include <net/iucv/af_iucv.h>
  31
  32 #define CONFIG_IUCV_SOCK_DEBUG 1
  33
  34 #define IPRMDATA 0x80
  35 #define VERSION "1.0"
  36
  37 static char iucv_userid[80];
  38
  39 static struct proto_ops iucv_sock_ops;
  40
  41 static struct proto iucv_proto = {
  42         .name           = "AF_IUCV",
  43         .owner          = THIS_MODULE,
  44         .obj_size       = sizeof(struct iucv_sock),
  45 };
  46
  47 static void iucv_sock_kill(struct sock *sk);
  48 static void iucv_sock_close(struct sock *sk);
  49
  50 /* Call Back functions */
  51 static void iucv_callback_rx(struct iucv_path *, struct iucv_message *);
  52 static void iucv_callback_txdone(struct iucv_path *, struct iucv_message *);
  53 static void iucv_callback_connack(struct iucv_path *, u8 ipuser[16]);
  54 static int iucv_callback_connreq(struct iucv_path *, u8 ipvmid[8],
  55                                  u8 ipuser[16]);
  56 static void iucv_callback_connrej(struct iucv_path *, u8 ipuser[16]);
  57
  58 static struct iucv_sock_list iucv_sk_list = {
  59         .lock = __RW_LOCK_UNLOCKED(iucv_sk_list.lock),
  60         .autobind_name = ATOMIC_INIT(0)
  61 };
  62
  63 static struct iucv_handler af_iucv_handler = {
  64         .path_pending     = iucv_callback_connreq,
  65         .path_complete    = iucv_callback_connack,
  66         .path_severed     = iucv_callback_connrej,
  67         .message_pending  = iucv_callback_rx,
  68         .message_complete = iucv_callback_txdone
  69 };
  70
  71 static inline void high_nmcpy(unsigned char *dst, char *src)
  72 {
  73        memcpy(dst, src, 8);
  74 }
  75
  76 static inline void low_nmcpy(unsigned char *dst, char *src)
  77 {
  78        memcpy(&dst[8], src, 8);
  79 }
  80
  81 /* Timers */
  82 static void iucv_sock_timeout(unsigned long arg)
  83 {
  84         struct sock *sk = (struct sock *)arg;
  85
  86         bh_lock_sock(sk);
  87         sk->sk_err = ETIMEDOUT;
  88         sk->sk_state_change(sk);
  89         bh_unlock_sock(sk);
  90
  91         iucv_sock_kill(sk);
  92         sock_put(sk);
  93 }
  94
  95 static void iucv_sock_clear_timer(struct sock *sk)
  96 {
  97         sk_stop_timer(sk, &sk->sk_timer);
  98 }
  99
 100 static struct sock *__iucv_get_sock_by_name(char *nm)
 101 {
 102         struct sock *sk;
 103         struct hlist_node *node;
 104
 105         sk_for_each(sk, node, &iucv_sk_list.head)
 106                 if (!memcmp(&iucv_sk(sk)->src_name, nm, 8))
 107                         return sk;
 108
 109         return NULL;
 110 }
 111
 112 static void iucv_sock_destruct(struct sock *sk)
 113 {
 114         skb_queue_purge(&sk->sk_receive_queue);
 115         skb_queue_purge(&sk->sk_write_queue);
 116 }
 117
 118 /* Cleanup Listen */
 119 static void iucv_sock_cleanup_listen(struct sock *parent)
 120 {
 121         struct sock *sk;
 122
 123         /* Close non-accepted connections */
 124         while ((sk = iucv_accept_dequeue(parent, NULL))) {
 125                 iucv_sock_close(sk);
 126                 iucv_sock_kill(sk);
 127         }
 128
 129         parent->sk_state = IUCV_CLOSED;
 130         sock_set_flag(parent, SOCK_ZAPPED);
 131 }
 132
 133 /* Kill socket */
 134 static void iucv_sock_kill(struct sock *sk)
 135 {
 136         if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket)
 137                 return;
 138
 139         iucv_sock_unlink(&iucv_sk_list, sk);
 140         sock_set_flag(sk, SOCK_DEAD);
 141         sock_put(sk);
 142 }
 143
 144 /* Close an IUCV socket */
 145 static void iucv_sock_close(struct sock *sk)
 146 {
 147         unsigned char user_data[16];
 148         struct iucv_sock *iucv = iucv_sk(sk);
 149         int err;
 150         unsigned long timeo;
 151
 152         iucv_sock_clear_timer(sk);
 153         lock_sock(sk);
 154
 155         switch (sk->sk_state) {
 156         case IUCV_LISTEN:
 157                 iucv_sock_cleanup_listen(sk);
 158                 break;
 159
 160         case IUCV_CONNECTED:
 161         case IUCV_DISCONN:
 162                 err = 0;
 163
 164                 sk->sk_state = IUCV_CLOSING;
 165                 sk->sk_state_change(sk);
 166
 167                 if (!skb_queue_empty(&iucv->send_skb_q)) {
 168                         if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime)
 169                                 timeo = sk->sk_lingertime;
 170                         else
 171                                 timeo = IUCV_DISCONN_TIMEOUT;
 172                         err = iucv_sock_wait_state(sk, IUCV_CLOSED, 0, timeo);
 173                 }
 174
 175                 sk->sk_state = IUCV_CLOSED;
 176                 sk->sk_state_change(sk);
 177
 178                 if (iucv->path) {
 179                         low_nmcpy(user_data, iucv->src_name);
 180                         high_nmcpy(user_data, iucv->dst_name);
 181                         ASCEBC(user_data, sizeof(user_data));
 182                         err = iucv_path_sever(iucv->path, user_data);
 183                         iucv_path_free(iucv->path);
 184                         iucv->path = NULL;
 185                 }
 186
 187                 sk->sk_err = ECONNRESET;
 188                 sk->sk_state_change(sk);
 189
 190                 skb_queue_purge(&iucv->send_skb_q);
 191                 skb_queue_purge(&iucv->backlog_skb_q);
 192
 193                 sock_set_flag(sk, SOCK_ZAPPED);
 194                 break;
 195
 196         default:
 197                 sock_set_flag(sk, SOCK_ZAPPED);
 198                 break;
 199         }
 200
 201         release_sock(sk);
 202         iucv_sock_kill(sk);
 203 }
 204
 205 static void iucv_sock_init(struct sock *sk, struct sock *parent)
 206 {
 207         if (parent)
 208                 sk->sk_type = parent->sk_type;
 209 }
 210
 211 static struct sock *iucv_sock_alloc(struct socket *sock, int proto, gfp_t prio)
 212 {
 213         struct sock *sk;
 214
 215         sk = sk_alloc(&init_net, PF_IUCV, prio, &iucv_proto);
 216         if (!sk)
 217                 return NULL;
 218
 219         sock_init_data(sock, sk);
 220         INIT_LIST_HEAD(&iucv_sk(sk)->accept_q);
 221         spin_lock_init(&iucv_sk(sk)->accept_q_lock);
 222         skb_queue_head_init(&iucv_sk(sk)->send_skb_q);
 223         INIT_LIST_HEAD(&iucv_sk(sk)->message_q.list);
 224         spin_lock_init(&iucv_sk(sk)->message_q.lock);
 225         skb_queue_head_init(&iucv_sk(sk)->backlog_skb_q);
 226         iucv_sk(sk)->send_tag = 0;
 227
 228         sk->sk_destruct = iucv_sock_destruct;
 229         sk->sk_sndtimeo = IUCV_CONN_TIMEOUT;
 230         sk->sk_allocation = GFP_DMA;
 231
 232         sock_reset_flag(sk, SOCK_ZAPPED);
 233
 234         sk->sk_protocol = proto;
 235         sk->sk_state    = IUCV_OPEN;
 236
 237         setup_timer(&sk->sk_timer, iucv_sock_timeout, (unsigned long)sk);
 238
 239         iucv_sock_link(&iucv_sk_list, sk);
 240         return sk;
 241 }
 242
 243 /* Create an IUCV socket */
 244 static int iucv_sock_create(struct net *net, struct socket *sock, int protocol)
 245 {
 246         struct sock *sk;
 247
 248         if (sock->type != SOCK_STREAM)
 249                 return -ESOCKTNOSUPPORT;
 250
 251         sock->state = SS_UNCONNECTED;
 252         sock->ops = &iucv_sock_ops;
 253
 254         sk = iucv_sock_alloc(sock, protocol, GFP_KERNEL);
 255         if (!sk)
 256                 return -ENOMEM;
 257
 258         iucv_sock_init(sk, NULL);
 259
 260         return 0;
 261 }
 262
 263 void iucv_sock_link(struct iucv_sock_list *l, struct sock *sk)
 264 {
 265         write_lock_bh(&l->lock);
 266         sk_add_node(sk, &l->head);
 267         write_unlock_bh(&l->lock);
 268 }
 269
 270 void iucv_sock_unlink(struct iucv_sock_list *l, struct sock *sk)
 271 {
 272         write_lock_bh(&l->lock);
 273         sk_del_node_init(sk);
 274         write_unlock_bh(&l->lock);
 275 }
 276
 277 void iucv_accept_enqueue(struct sock *parent, struct sock *sk)
 278 {
 279         unsigned long flags;
 280         struct iucv_sock *par = iucv_sk(parent);
 281
 282         sock_hold(sk);
 283         spin_lock_irqsave(&par->accept_q_lock, flags);
 284         list_add_tail(&iucv_sk(sk)->accept_q, &par->accept_q);
 285         spin_unlock_irqrestore(&par->accept_q_lock, flags);
 286         iucv_sk(sk)->parent = parent;
 287         parent->sk_ack_backlog++;
 288 }
 289
 290 void iucv_accept_unlink(struct sock *sk)
 291 {
 292         unsigned long flags;
 293         struct iucv_sock *par = iucv_sk(iucv_sk(sk)->parent);
 294
 295         spin_lock_irqsave(&par->accept_q_lock, flags);
 296         list_del_init(&iucv_sk(sk)->accept_q);
 297         spin_unlock_irqrestore(&par->accept_q_lock, flags);
 298         iucv_sk(sk)->parent->sk_ack_backlog--;
 299         iucv_sk(sk)->parent = NULL;
 300         sock_put(sk);
 301 }
 302
 303 struct sock *iucv_accept_dequeue(struct sock *parent, struct socket *newsock)
 304 {
 305         struct iucv_sock *isk, *n;
 306         struct sock *sk;
 307
 308         list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
 309                 sk = (struct sock *) isk;
 310                 lock_sock(sk);
 311
 312                 if (sk->sk_state == IUCV_CLOSED) {
 313                         iucv_accept_unlink(sk);
 314                         release_sock(sk);
 315                         continue;
 316                 }
 317
 318                 if (sk->sk_state == IUCV_CONNECTED ||
 319                     sk->sk_state == IUCV_SEVERED ||
 320                     !newsock) {
 321                         iucv_accept_unlink(sk);
 322                         if (newsock)
 323                                 sock_graft(sk, newsock);
 324
 325                         if (sk->sk_state == IUCV_SEVERED)
 326                                 sk->sk_state = IUCV_DISCONN;
 327
 328                         release_sock(sk);
 329                         return sk;
 330                 }
 331
 332                 release_sock(sk);
 333         }
 334         return NULL;
 335 }
 336
 337 int iucv_sock_wait_state(struct sock *sk, int state, int state2,
 338                          unsigned long timeo)
 339 {
 340         DECLARE_WAITQUEUE(wait, current);
 341         int err = 0;
 342
 343         add_wait_queue(sk->sk_sleep, &wait);
 344         while (sk->sk_state != state && sk->sk_state != state2) {
 345                 set_current_state(TASK_INTERRUPTIBLE);
 346
 347                 if (!timeo) {
 348                         err = -EAGAIN;
 349                         break;
 350                 }
 351
 352                 if (signal_pending(current)) {
 353                         err = sock_intr_errno(timeo);
 354                         break;
 355                 }
 356
 357                 release_sock(sk);
 358                 timeo = schedule_timeout(timeo);
 359                 lock_sock(sk);
 360
 361                 err = sock_error(sk);
 362                 if (err)
 363                         break;
 364         }
 365         set_current_state(TASK_RUNNING);
 366         remove_wait_queue(sk->sk_sleep, &wait);
 367         return err;
 368 }
 369
 370 /* Bind an unbound socket */
 371 static int iucv_sock_bind(struct socket *sock, struct sockaddr *addr,
 372                           int addr_len)
 373 {
 374         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
 375         struct sock *sk = sock->sk;
 376         struct iucv_sock *iucv;
 377         int err;
 378
 379         /* Verify the input sockaddr */
 380         if (!addr || addr->sa_family != AF_IUCV)
 381                 return -EINVAL;
 382
 383         lock_sock(sk);
 384         if (sk->sk_state != IUCV_OPEN) {
 385                 err = -EBADFD;
 386                 goto done;
 387         }
 388
 389         write_lock_bh(&iucv_sk_list.lock);
 390
 391         iucv = iucv_sk(sk);
 392         if (__iucv_get_sock_by_name(sa->siucv_name)) {
 393                 err = -EADDRINUSE;
 394                 goto done_unlock;
 395         }
 396         if (iucv->path) {
 397                 err = 0;
 398                 goto done_unlock;
 399         }
 400
 401         /* Bind the socket */
 402         memcpy(iucv->src_name, sa->siucv_name, 8);
 403
 404         /* Copy the user id */
 405         memcpy(iucv->src_user_id, iucv_userid, 8);
 406         sk->sk_state = IUCV_BOUND;
 407         err = 0;
 408
 409 done_unlock:
 410         /* Release the socket list lock */
 411         write_unlock_bh(&iucv_sk_list.lock);
 412 done:
 413         release_sock(sk);
 414         return err;
 415 }
 416
 417 /* Automatically bind an unbound socket */
 418 static int iucv_sock_autobind(struct sock *sk)
 419 {
 420         struct iucv_sock *iucv = iucv_sk(sk);
 421         char query_buffer[80];
 422         char name[12];
 423         int err = 0;
 424
 425         /* Set the userid and name */
 426         cpcmd("QUERY USERID", query_buffer, sizeof(query_buffer), &err);
 427         if (unlikely(err))
 428                 return -EPROTO;
 429
 430         memcpy(iucv->src_user_id, query_buffer, 8);
 431
 432         write_lock_bh(&iucv_sk_list.lock);
 433
 434         sprintf(name, "%08x", atomic_inc_return(&iucv_sk_list.autobind_name));
 435         while (__iucv_get_sock_by_name(name)) {
 436                 sprintf(name, "%08x",
 437                         atomic_inc_return(&iucv_sk_list.autobind_name));
 438         }
 439
 440         write_unlock_bh(&iucv_sk_list.lock);
 441
 442         memcpy(&iucv->src_name, name, 8);
 443
 444         return err;
 445 }
 446
 447 /* Connect an unconnected socket */
 448 static int iucv_sock_connect(struct socket *sock, struct sockaddr *addr,
 449                              int alen, int flags)
 450 {
 451         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
 452         struct sock *sk = sock->sk;
 453         struct iucv_sock *iucv;
 454         unsigned char user_data[16];
 455         int err;
 456
 457         if (addr->sa_family != AF_IUCV || alen < sizeof(struct sockaddr_iucv))
 458                 return -EINVAL;
 459
 460         if (sk->sk_state != IUCV_OPEN && sk->sk_state != IUCV_BOUND)
 461                 return -EBADFD;
 462
 463         if (sk->sk_type != SOCK_STREAM)
 464                 return -EINVAL;
 465
 466         iucv = iucv_sk(sk);
 467
 468         if (sk->sk_state == IUCV_OPEN) {
 469                 err = iucv_sock_autobind(sk);
 470                 if (unlikely(err))
 471                         return err;
 472         }
 473
 474         lock_sock(sk);
 475
 476         /* Set the destination information */
 477         memcpy(iucv_sk(sk)->dst_user_id, sa->siucv_user_id, 8);
 478         memcpy(iucv_sk(sk)->dst_name, sa->siucv_name, 8);
 479
 480         high_nmcpy(user_data, sa->siucv_name);
 481         low_nmcpy(user_data, iucv_sk(sk)->src_name);
 482         ASCEBC(user_data, sizeof(user_data));
 483
 484         iucv = iucv_sk(sk);
 485         /* Create path. */
 486         iucv->path = iucv_path_alloc(IUCV_QUEUELEN_DEFAULT,
 487                                      IPRMDATA, GFP_KERNEL);
 488         if (!iucv->path) {
 489                 err = -ENOMEM;
 490                 goto done;
 491         }
 492         err = iucv_path_connect(iucv->path, &af_iucv_handler,
 493                                 sa->siucv_user_id, NULL, user_data, sk);
 494         if (err) {
 495                 iucv_path_free(iucv->path);
 496                 iucv->path = NULL;
 497                 err = -ECONNREFUSED;
 498                 goto done;
 499         }
 500
 501         if (sk->sk_state != IUCV_CONNECTED) {
 502                 err = iucv_sock_wait_state(sk, IUCV_CONNECTED, IUCV_DISCONN,
 503                                 sock_sndtimeo(sk, flags & O_NONBLOCK));
 504         }
 505
 506         if (sk->sk_state == IUCV_DISCONN) {
 507                 release_sock(sk);
 508                 return -ECONNREFUSED;
 509         }
 510 done:
 511         release_sock(sk);
 512         return err;
 513 }
 514
 515 /* Move a socket into listening state. */
 516 static int iucv_sock_listen(struct socket *sock, int backlog)
 517 {
 518         struct sock *sk = sock->sk;
 519         int err;
 520
 521         lock_sock(sk);
 522
 523         err = -EINVAL;
 524         if (sk->sk_state != IUCV_BOUND || sock->type != SOCK_STREAM)
 525                 goto done;
 526
 527         sk->sk_max_ack_backlog = backlog;
 528         sk->sk_ack_backlog = 0;
 529         sk->sk_state = IUCV_LISTEN;
 530         err = 0;
 531
 532 done:
 533         release_sock(sk);
 534         return err;
 535 }
 536
 537 /* Accept a pending connection */
 538 static int iucv_sock_accept(struct socket *sock, struct socket *newsock,
 539                             int flags)
 540 {
 541         DECLARE_WAITQUEUE(wait, current);
 542         struct sock *sk = sock->sk, *nsk;
 543         long timeo;
 544         int err = 0;
 545
 546         lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
 547
 548         if (sk->sk_state != IUCV_LISTEN) {
 549                 err = -EBADFD;
 550                 goto done;
 551         }
 552
 553         timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
 554
 555         /* Wait for an incoming connection */
 556         add_wait_queue_exclusive(sk->sk_sleep, &wait);
 557         while (!(nsk = iucv_accept_dequeue(sk, newsock))) {
 558                 set_current_state(TASK_INTERRUPTIBLE);
 559                 if (!timeo) {
 560                         err = -EAGAIN;
 561                         break;
 562                 }
 563
 564                 release_sock(sk);
 565                 timeo = schedule_timeout(timeo);
 566                 lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
 567
 568                 if (sk->sk_state != IUCV_LISTEN) {
 569                         err = -EBADFD;
 570                         break;
 571                 }
 572
 573                 if (signal_pending(current)) {
 574                         err = sock_intr_errno(timeo);
 575                         break;
 576                 }
 577         }
 578
 579         set_current_state(TASK_RUNNING);
 580         remove_wait_queue(sk->sk_sleep, &wait);
 581
 582         if (err)
 583                 goto done;
 584
 585         newsock->state = SS_CONNECTED;
 586
 587 done:
 588         release_sock(sk);
 589         return err;
 590 }
 591
 592 static int iucv_sock_getname(struct socket *sock, struct sockaddr *addr,
 593                              int *len, int peer)
 594 {
 595         struct sockaddr_iucv *siucv = (struct sockaddr_iucv *) addr;
 596         struct sock *sk = sock->sk;
 597
 598         addr->sa_family = AF_IUCV;
 599         *len = sizeof(struct sockaddr_iucv);
 600
 601         if (peer) {
 602                 memcpy(siucv->siucv_user_id, iucv_sk(sk)->dst_user_id, 8);
 603                 memcpy(siucv->siucv_name, &iucv_sk(sk)->dst_name, 8);
 604         } else {
 605                 memcpy(siucv->siucv_user_id, iucv_sk(sk)->src_user_id, 8);
 606                 memcpy(siucv->siucv_name, iucv_sk(sk)->src_name, 8);
 607         }
 608         memset(&siucv->siucv_port, 0, sizeof(siucv->siucv_port));
 609         memset(&siucv->siucv_addr, 0, sizeof(siucv->siucv_addr));
 610         memset(siucv->siucv_nodeid, 0, sizeof(siucv->siucv_nodeid));
 611
 612         return 0;
 613 }
 614
 615 static int iucv_sock_sendmsg(struct kiocb *iocb, struct socket *sock,
 616                              struct msghdr *msg, size_t len)
 617 {
 618         struct sock *sk = sock->sk;
 619         struct iucv_sock *iucv = iucv_sk(sk);
 620         struct sk_buff *skb;
 621         struct iucv_message txmsg;
 622         char user_id[9];
 623         char appl_id[9];
 624         int err;
 625
 626         err = sock_error(sk);
 627         if (err)
 628                 return err;
 629
 630         if (msg->msg_flags & MSG_OOB)
 631                 return -EOPNOTSUPP;
 632
 633         lock_sock(sk);
 634
 635         if (sk->sk_shutdown & SEND_SHUTDOWN) {
 636                 err = -EPIPE;
 637                 goto out;
 638         }
 639
 640         if (sk->sk_state == IUCV_CONNECTED) {
 641                 if (!(skb = sock_alloc_send_skb(sk, len,
 642                                                 msg->msg_flags & MSG_DONTWAIT,
 643                                                 &err)))
 644                         goto out;
 645
 646                 if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) {
 647                         err = -EFAULT;
 648                         goto fail;
 649                 }
 650
 651                 txmsg.class = 0;
 652                 memcpy(&txmsg.class, skb->data, skb->len >= 4 ? 4 : skb->len);
 653                 txmsg.tag = iucv->send_tag++;
 654                 memcpy(skb->cb, &txmsg.tag, 4);
 655                 skb_queue_tail(&iucv->send_skb_q, skb);
 656                 err = iucv_message_send(iucv->path, &txmsg, 0, 0,
 657                                         (void *) skb->data, skb->len);
 658                 if (err) {
 659                         if (err == 3) {
 660                                 user_id[8] = 0;
 661                                 memcpy(user_id, iucv->dst_user_id, 8);
 662                                 appl_id[8] = 0;
 663                                 memcpy(appl_id, iucv->dst_name, 8);
 664                                 pr_err("Application %s on z/VM guest %s"
 665                                        " exceeds message limit\n",
 666                                        user_id, appl_id);
 667                         }
 668                         skb_unlink(skb, &iucv->send_skb_q);
 669                         err = -EPIPE;
 670                         goto fail;
 671                 }
 672
 673         } else {
 674                 err = -ENOTCONN;
 675                 goto out;
 676         }
 677
 678         release_sock(sk);
 679         return len;
 680
 681 fail:
 682         kfree_skb(skb);
 683 out:
 684         release_sock(sk);
 685         return err;
 686 }
 687
 688 static int iucv_fragment_skb(struct sock *sk, struct sk_buff *skb, int len)
 689 {
 690         int dataleft, size, copied = 0;
 691         struct sk_buff *nskb;
 692
 693         dataleft = len;
 694         while (dataleft) {
 695                 if (dataleft >= sk->sk_rcvbuf / 4)
 696                         size = sk->sk_rcvbuf / 4;
 697                 else
 698                         size = dataleft;
 699
 700                 nskb = alloc_skb(size, GFP_ATOMIC | GFP_DMA);
 701                 if (!nskb)
 702                         return -ENOMEM;
 703
 704                 memcpy(nskb->data, skb->data + copied, size);
 705                 copied += size;
 706                 dataleft -= size;
 707
 708                 skb_reset_transport_header(nskb);
 709                 skb_reset_network_header(nskb);
 710                 nskb->len = size;
 711
 712                 skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, nskb);
 713         }
 714
 715         return 0;
 716 }
 717
 718 static void iucv_process_message(struct sock *sk, struct sk_buff *skb,
 719                                  struct iucv_path *path,
 720                                  struct iucv_message *msg)
 721 {
 722         int rc;
 723
 724         if (msg->flags & IPRMDATA) {
 725                 skb->data = NULL;
 726                 skb->len = 0;
 727         } else {
 728                 rc = iucv_message_receive(path, msg, 0, skb->data,
 729                                           msg->length, NULL);
 730                 if (rc) {
 731                         kfree_skb(skb);
 732                         return;
 733                 }
 734                 if (skb->truesize >= sk->sk_rcvbuf / 4) {
 735                         rc = iucv_fragment_skb(sk, skb, msg->length);
 736                         kfree_skb(skb);
 737                         skb = NULL;
 738                         if (rc) {
 739                                 iucv_path_sever(path, NULL);
 740                                 return;
 741                         }
 742                         skb = skb_dequeue(&iucv_sk(sk)->backlog_skb_q);
 743                 } else {
 744                         skb_reset_transport_header(skb);
 745                         skb_reset_network_header(skb);
 746                         skb->len = msg->length;
 747                 }
 748         }
 749
 750         if (sock_queue_rcv_skb(sk, skb))
 751                 skb_queue_head(&iucv_sk(sk)->backlog_skb_q, skb);
 752 }
 753
 754 static void iucv_process_message_q(struct sock *sk)
 755 {
 756         struct iucv_sock *iucv = iucv_sk(sk);
 757         struct sk_buff *skb;
 758         struct sock_msg_q *p, *n;
 759
 760         list_for_each_entry_safe(p, n, &iucv->message_q.list, list) {
 761                 skb = alloc_skb(p->msg.length, GFP_ATOMIC | GFP_DMA);
 762                 if (!skb)
 763                         break;
 764                 iucv_process_message(sk, skb, p->path, &p->msg);
 765                 list_del(&p->list);
 766                 kfree(p);
 767                 if (!skb_queue_empty(&iucv->backlog_skb_q))
 768                         break;
 769         }
 770 }
 771
 772 static int iucv_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
 773                              struct msghdr *msg, size_t len, int flags)
 774 {
 775         int noblock = flags & MSG_DONTWAIT;
 776         struct sock *sk = sock->sk;
 777         struct iucv_sock *iucv = iucv_sk(sk);
 778         int target, copied = 0;
 779         struct sk_buff *skb, *rskb, *cskb;
 780         int err = 0;
 781
 782         if ((sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_SEVERED) &&
 783             skb_queue_empty(&iucv->backlog_skb_q) &&
 784             skb_queue_empty(&sk->sk_receive_queue) &&
 785             list_empty(&iucv->message_q.list))
 786                 return 0;
 787
 788         if (flags & (MSG_OOB))
 789                 return -EOPNOTSUPP;
 790
 791         target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
 792
 793         skb = skb_recv_datagram(sk, flags, noblock, &err);
 794         if (!skb) {
 795                 if (sk->sk_shutdown & RCV_SHUTDOWN)
 796                         return 0;
 797                 return err;
 798         }
 799
 800         copied = min_t(unsigned int, skb->len, len);
 801
 802         cskb = skb;
 803         if (memcpy_toiovec(msg->msg_iov, cskb->data, copied)) {
 804                 skb_queue_head(&sk->sk_receive_queue, skb);
 805                 if (copied == 0)
 806                         return -EFAULT;
 807                 goto done;
 808         }
 809
 810         len -= copied;
 811
 812         /* Mark read part of skb as used */
 813         if (!(flags & MSG_PEEK)) {
 814                 skb_pull(skb, copied);
 815
 816                 if (skb->len) {
 817                         skb_queue_head(&sk->sk_receive_queue, skb);
 818                         goto done;
 819                 }
 820
 821                 kfree_skb(skb);
 822
 823                 /* Queue backlog skbs */
 824                 rskb = skb_dequeue(&iucv->backlog_skb_q);
 825                 while (rskb) {
 826                         if (sock_queue_rcv_skb(sk, rskb)) {
 827                                 skb_queue_head(&iucv->backlog_skb_q,
 828                                                 rskb);
 829                                 break;
 830                         } else {
 831                                 rskb = skb_dequeue(&iucv->backlog_skb_q);
 832                         }
 833                 }
 834                 if (skb_queue_empty(&iucv->backlog_skb_q)) {
 835                         spin_lock_bh(&iucv->message_q.lock);
 836                         if (!list_empty(&iucv->message_q.list))
 837                                 iucv_process_message_q(sk);
 838                         spin_unlock_bh(&iucv->message_q.lock);
 839                 }
 840
 841         } else
 842                 skb_queue_head(&sk->sk_receive_queue, skb);
 843
 844 done:
 845         return err ? : copied;
 846 }
 847
 848 static inline unsigned int iucv_accept_poll(struct sock *parent)
 849 {
 850         struct iucv_sock *isk, *n;
 851         struct sock *sk;
 852
 853         list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
 854                 sk = (struct sock *) isk;
 855
 856                 if (sk->sk_state == IUCV_CONNECTED)
 857                         return POLLIN | POLLRDNORM;
 858         }
 859
 860         return 0;
 861 }
 862
 863 unsigned int iucv_sock_poll(struct file *file, struct socket *sock,
 864                             poll_table *wait)
 865 {
 866         struct sock *sk = sock->sk;
 867         unsigned int mask = 0;
 868
 869         poll_wait(file, sk->sk_sleep, wait);
 870
 871         if (sk->sk_state == IUCV_LISTEN)
 872                 return iucv_accept_poll(sk);
 873
 874         if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
 875                 mask |= POLLERR;
 876
 877         if (sk->sk_shutdown & RCV_SHUTDOWN)
 878                 mask |= POLLRDHUP;
 879
 880         if (sk->sk_shutdown == SHUTDOWN_MASK)
 881                 mask |= POLLHUP;
 882
 883         if (!skb_queue_empty(&sk->sk_receive_queue) ||
 884             (sk->sk_shutdown & RCV_SHUTDOWN))
 885                 mask |= POLLIN | POLLRDNORM;
 886
 887         if (sk->sk_state == IUCV_CLOSED)
 888                 mask |= POLLHUP;
 889
 890         if (sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_SEVERED)
 891                 mask |= POLLIN;
 892
 893         if (sock_writeable(sk))
 894                 mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
 895         else
 896                 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
 897
 898         return mask;
 899 }
 900
 901 static int iucv_sock_shutdown(struct socket *sock, int how)
 902 {
 903         struct sock *sk = sock->sk;
 904         struct iucv_sock *iucv = iucv_sk(sk);
 905         struct iucv_message txmsg;
 906         int err = 0;
 907         u8 prmmsg[8] = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01};
 908
 909         how++;
 910
 911         if ((how & ~SHUTDOWN_MASK) || !how)
 912                 return -EINVAL;
 913
 914         lock_sock(sk);
 915         switch (sk->sk_state) {
 916         case IUCV_CLOSED:
 917                 err = -ENOTCONN;
 918                 goto fail;
 919
 920         default:
 921                 sk->sk_shutdown |= how;
 922                 break;
 923         }
 924
 925         if (how == SEND_SHUTDOWN || how == SHUTDOWN_MASK) {
 926                 txmsg.class = 0;
 927                 txmsg.tag = 0;
 928                 err = iucv_message_send(iucv->path, &txmsg, IUCV_IPRMDATA, 0,
 929                                         (void *) prmmsg, 8);
 930                 if (err) {
 931                         switch (err) {
 932                         case 1:
 933                                 err = -ENOTCONN;
 934                                 break;
 935                         case 2:
 936                                 err = -ECONNRESET;
 937                                 break;
 938                         default:
 939                                 err = -ENOTCONN;
 940                                 break;
 941                         }
 942                 }
 943         }
 944
 945         if (how == RCV_SHUTDOWN || how == SHUTDOWN_MASK) {
 946                 err = iucv_path_quiesce(iucv_sk(sk)->path, NULL);
 947                 if (err)
 948                         err = -ENOTCONN;
 949
 950                 skb_queue_purge(&sk->sk_receive_queue);
 951         }
 952
 953         /* Wake up anyone sleeping in poll */
 954         sk->sk_state_change(sk);
 955
 956 fail:
 957         release_sock(sk);
 958         return err;
 959 }
 960
 961 static int iucv_sock_release(struct socket *sock)
 962 {
 963         struct sock *sk = sock->sk;
 964         int err = 0;
 965
 966         if (!sk)
 967                 return 0;
 968
 969         iucv_sock_close(sk);
 970
 971         /* Unregister with IUCV base support */
 972         if (iucv_sk(sk)->path) {
 973                 iucv_path_sever(iucv_sk(sk)->path, NULL);
 974                 iucv_path_free(iucv_sk(sk)->path);
 975                 iucv_sk(sk)->path = NULL;
 976         }
 977
 978         sock_orphan(sk);
 979         iucv_sock_kill(sk);
 980         return err;
 981 }
 982
 983 /* Callback wrappers - called from iucv base support */
 984 static int iucv_callback_connreq(struct iucv_path *path,
 985                                  u8 ipvmid[8], u8 ipuser[16])
 986 {
 987         unsigned char user_data[16];
 988         unsigned char nuser_data[16];
 989         unsigned char src_name[8];
 990         struct hlist_node *node;
 991         struct sock *sk, *nsk;
 992         struct iucv_sock *iucv, *niucv;
 993         int err;
 994
 995         memcpy(src_name, ipuser, 8);
 996         EBCASC(src_name, 8);
 997         /* Find out if this path belongs to af_iucv. */
 998         read_lock(&iucv_sk_list.lock);
 999         iucv = NULL;
1000         sk = NULL;
1001         sk_for_each(sk, node, &iucv_sk_list.head)
1002                 if (sk->sk_state == IUCV_LISTEN &&
1003                     !memcmp(&iucv_sk(sk)->src_name, src_name, 8)) {
1004                         /*
1005                          * Found a listening socket with
1006                          * src_name == ipuser[0-7].
1007                          */
1008                         iucv = iucv_sk(sk);
1009                         break;
1010                 }
1011         read_unlock(&iucv_sk_list.lock);
1012         if (!iucv)
1013                 /* No socket found, not one of our paths. */
1014                 return -EINVAL;
1015
1016         bh_lock_sock(sk);
1017
1018         /* Check if parent socket is listening */
1019         low_nmcpy(user_data, iucv->src_name);
1020         high_nmcpy(user_data, iucv->dst_name);
1021         ASCEBC(user_data, sizeof(user_data));
1022         if (sk->sk_state != IUCV_LISTEN) {
1023                 err = iucv_path_sever(path, user_data);
1024                 goto fail;
1025         }
1026
1027         /* Check for backlog size */
1028         if (sk_acceptq_is_full(sk)) {
1029                 err = iucv_path_sever(path, user_data);
1030                 goto fail;
1031         }
1032
1033         /* Create the new socket */
1034         nsk = iucv_sock_alloc(NULL, SOCK_STREAM, GFP_ATOMIC);
1035         if (!nsk) {
1036                 err = iucv_path_sever(path, user_data);
1037                 goto fail;
1038         }
1039
1040         niucv = iucv_sk(nsk);
1041         iucv_sock_init(nsk, sk);
1042
1043         /* Set the new iucv_sock */
1044         memcpy(niucv->dst_name, ipuser + 8, 8);
1045         EBCASC(niucv->dst_name, 8);
1046         memcpy(niucv->dst_user_id, ipvmid, 8);
1047         memcpy(niucv->src_name, iucv->src_name, 8);
1048         memcpy(niucv->src_user_id, iucv->src_user_id, 8);
1049         niucv->path = path;
1050
1051         /* Call iucv_accept */
1052         high_nmcpy(nuser_data, ipuser + 8);
1053         memcpy(nuser_data + 8, niucv->src_name, 8);
1054         ASCEBC(nuser_data + 8, 8);
1055
1056         path->msglim = IUCV_QUEUELEN_DEFAULT;
1057         err = iucv_path_accept(path, &af_iucv_handler, nuser_data, nsk);
1058         if (err) {
1059                 err = iucv_path_sever(path, user_data);
1060                 goto fail;
1061         }
1062
1063         iucv_accept_enqueue(sk, nsk);
1064
1065         /* Wake up accept */
1066         nsk->sk_state = IUCV_CONNECTED;
1067         sk->sk_data_ready(sk, 1);
1068         err = 0;
1069 fail:
1070         bh_unlock_sock(sk);
1071         return 0;
1072 }
1073
1074 static void iucv_callback_connack(struct iucv_path *path, u8 ipuser[16])
1075 {
1076         struct sock *sk = path->private;
1077
1078         sk->sk_state = IUCV_CONNECTED;
1079         sk->sk_state_change(sk);
1080 }
1081
1082 static void iucv_callback_rx(struct iucv_path *path, struct iucv_message *msg)
1083 {
1084         struct sock *sk = path->private;
1085         struct iucv_sock *iucv = iucv_sk(sk);
1086         struct sk_buff *skb;
1087         struct sock_msg_q *save_msg;
1088         int len;
1089
1090         if (sk->sk_shutdown & RCV_SHUTDOWN)
1091                 return;
1092
1093         if (!list_empty(&iucv->message_q.list) ||
1094             !skb_queue_empty(&iucv->backlog_skb_q))
1095                 goto save_message;
1096
1097         len = atomic_read(&sk->sk_rmem_alloc);
1098         len += msg->length + sizeof(struct sk_buff);
1099         if (len > sk->sk_rcvbuf)
1100                 goto save_message;
1101
1102         skb = alloc_skb(msg->length, GFP_ATOMIC | GFP_DMA);
1103         if (!skb)
1104                 goto save_message;
1105
1106         spin_lock(&iucv->message_q.lock);
1107         iucv_process_message(sk, skb, path, msg);
1108         spin_unlock(&iucv->message_q.lock);
1109
1110         return;
1111
1112 save_message:
1113         save_msg = kzalloc(sizeof(struct sock_msg_q), GFP_ATOMIC | GFP_DMA);
1114         if (!save_msg)
1115                 return;
1116         save_msg->path = path;
1117         save_msg->msg = *msg;
1118
1119         spin_lock(&iucv->message_q.lock);
1120         list_add_tail(&save_msg->list, &iucv->message_q.list);
1121         spin_unlock(&iucv->message_q.lock);
1122 }
1123
1124 static void iucv_callback_txdone(struct iucv_path *path,
1125                                  struct iucv_message *msg)
1126 {
1127         struct sock *sk = path->private;
1128         struct sk_buff *this = NULL;
1129         struct sk_buff_head *list = &iucv_sk(sk)->send_skb_q;
1130         struct sk_buff *list_skb = list->next;
1131         unsigned long flags;
1132
1133         if (!skb_queue_empty(list)) {
1134                 spin_lock_irqsave(&list->lock, flags);
1135
1136                 while (list_skb != (struct sk_buff *)list) {
1137                         if (!memcmp(&msg->tag, list_skb->cb, 4)) {
1138                                 this = list_skb;
1139                                 break;
1140                         }
1141                         list_skb = list_skb->next;
1142                 }
1143                 if (this)
1144                         __skb_unlink(this, list);
1145
1146                 spin_unlock_irqrestore(&list->lock, flags);
1147
1148                 if (this)
1149                         kfree_skb(this);
1150         }
1151         BUG_ON(!this);
1152
1153         if (sk->sk_state == IUCV_CLOSING) {
1154                 if (skb_queue_empty(&iucv_sk(sk)->send_skb_q)) {
1155                         sk->sk_state = IUCV_CLOSED;
1156                         sk->sk_state_change(sk);
1157                 }
1158         }
1159
1160 }
1161
1162 static void iucv_callback_connrej(struct iucv_path *path, u8 ipuser[16])
1163 {
1164         struct sock *sk = path->private;
1165
1166         if (!list_empty(&iucv_sk(sk)->accept_q))
1167                 sk->sk_state = IUCV_SEVERED;
1168         else
1169                 sk->sk_state = IUCV_DISCONN;
1170
1171         sk->sk_state_change(sk);
1172 }
1173
1174 static struct proto_ops iucv_sock_ops = {
1175         .family         = PF_IUCV,
1176         .owner          = THIS_MODULE,
1177         .release        = iucv_sock_release,
1178         .bind           = iucv_sock_bind,
1179         .connect        = iucv_sock_connect,
1180         .listen         = iucv_sock_listen,
1181         .accept         = iucv_sock_accept,
1182         .getname        = iucv_sock_getname,
1183         .sendmsg        = iucv_sock_sendmsg,
1184         .recvmsg        = iucv_sock_recvmsg,
1185         .poll           = iucv_sock_poll,
1186         .ioctl          = sock_no_ioctl,
1187         .mmap           = sock_no_mmap,
1188         .socketpair     = sock_no_socketpair,
1189         .shutdown       = iucv_sock_shutdown,
1190         .setsockopt     = sock_no_setsockopt,
1191         .getsockopt     = sock_no_getsockopt
1192 };
1193
1194 static struct net_proto_family iucv_sock_family_ops = {
1195         .family = AF_IUCV,
1196         .owner  = THIS_MODULE,
1197         .create = iucv_sock_create,
1198 };
1199
1200 static int __init afiucv_init(void)
1201 {
1202         int err;
1203
1204         if (!MACHINE_IS_VM) {
1205                 pr_err("The af_iucv module cannot be loaded"
1206                        " without z/VM\n");
1207                 err = -EPROTONOSUPPORT;
1208                 goto out;
1209         }
1210         cpcmd("QUERY USERID", iucv_userid, sizeof(iucv_userid), &err);
1211         if (unlikely(err)) {
1212                 WARN_ON(err);
1213                 err = -EPROTONOSUPPORT;
1214                 goto out;
1215         }
1216
1217         err = iucv_register(&af_iucv_handler, 0);
1218         if (err)
1219                 goto out;
1220         err = proto_register(&iucv_proto, 0);
1221         if (err)
1222                 goto out_iucv;
1223         err = sock_register(&iucv_sock_family_ops);
1224         if (err)
1225                 goto out_proto;
1226         return 0;
1227
1228 out_proto:
1229         proto_unregister(&iucv_proto);
1230 out_iucv:
1231         iucv_unregister(&af_iucv_handler, 0);
1232 out:
1233         return err;
1234 }
1235
1236 static void __exit afiucv_exit(void)
1237 {
1238         sock_unregister(PF_IUCV);
1239         proto_unregister(&iucv_proto);
1240         iucv_unregister(&af_iucv_handler, 0);
1241 }
1242
1243 module_init(afiucv_init);
1244 module_exit(afiucv_exit);
1245
1246 MODULE_AUTHOR("Jennifer Hunt <jenhunt@us.ibm.com>");
1247 MODULE_DESCRIPTION("IUCV Sockets ver " VERSION);
1248 MODULE_VERSION(VERSION);
1249 MODULE_LICENSE("GPL");
1250 MODULE_ALIAS_NETPROTO(PF_IUCV);