net/iucv/af_iucv.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *  IUCV protocol stack for Linux on zSeries
   4  *
   5  *  Copyright IBM Corp. 2006, 2009
   6  *
   7  *  Author(s):  Jennifer Hunt <jenhunt@us.ibm.com>
   8  *              Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
   9  *  PM functions:
  10  *              Ursula Braun <ursula.braun@de.ibm.com>
  11  */
  12
  13 #define KMSG_COMPONENT "af_iucv"
  14 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  15
  16 #include <linux/module.h>
  17 #include <linux/netdevice.h>
  18 #include <linux/types.h>
  19 #include <linux/limits.h>
  20 #include <linux/list.h>
  21 #include <linux/errno.h>
  22 #include <linux/kernel.h>
  23 #include <linux/sched/signal.h>
  24 #include <linux/slab.h>
  25 #include <linux/skbuff.h>
  26 #include <linux/init.h>
  27 #include <linux/poll.h>
  28 #include <linux/security.h>
  29 #include <net/sock.h>
  30 #include <asm/ebcdic.h>
  31 #include <asm/cpcmd.h>
  32 #include <linux/kmod.h>
  33
  34 #include <net/iucv/af_iucv.h>
  35
  36 #define VERSION "1.2"
  37
  38 static char iucv_userid[80];
  39
  40 static struct proto iucv_proto = {
  41         .name           = "AF_IUCV",
  42         .owner          = THIS_MODULE,
  43         .obj_size       = sizeof(struct iucv_sock),
  44 };
  45
  46 static struct iucv_interface *pr_iucv;
  47
  48 /* special AF_IUCV IPRM messages */
  49 static const u8 iprm_shutdown[8] =
  50         {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01};
  51
  52 #define TRGCLS_SIZE     sizeof_field(struct iucv_message, class)
  53
  54 #define __iucv_sock_wait(sk, condition, timeo, ret)                     \
  55 do {                                                                    \
  56         DEFINE_WAIT(__wait);                                            \
  57         long __timeo = timeo;                                           \
  58         ret = 0;                                                        \
  59         prepare_to_wait(sk_sleep(sk), &__wait, TASK_INTERRUPTIBLE);     \
  60         while (!(condition)) {                                          \
  61                 if (!__timeo) {                                         \
  62                         ret = -EAGAIN;                                  \
  63                         break;                                          \
  64                 }                                                       \
  65                 if (signal_pending(current)) {                          \
  66                         ret = sock_intr_errno(__timeo);                 \
  67                         break;                                          \
  68                 }                                                       \
  69                 release_sock(sk);                                       \
  70                 __timeo = schedule_timeout(__timeo);                    \
  71                 lock_sock(sk);                                          \
  72                 ret = sock_error(sk);                                   \
  73                 if (ret)                                                \
  74                         break;                                          \
  75         }                                                               \
  76         finish_wait(sk_sleep(sk), &__wait);                             \
  77 } while (0)
  78
  79 #define iucv_sock_wait(sk, condition, timeo)                            \
  80 ({                                                                      \
  81         int __ret = 0;                                                  \
  82         if (!(condition))                                               \
  83                 __iucv_sock_wait(sk, condition, timeo, __ret);          \
  84         __ret;                                                          \
  85 })
  86
  87 static struct sock *iucv_accept_dequeue(struct sock *parent,
  88                                         struct socket *newsock);
  89 static void iucv_sock_kill(struct sock *sk);
  90 static void iucv_sock_close(struct sock *sk);
  91
  92 static void afiucv_hs_callback_txnotify(struct sk_buff *, enum iucv_tx_notify);
  93
  94 /* Call Back functions */
  95 static void iucv_callback_rx(struct iucv_path *, struct iucv_message *);
  96 static void iucv_callback_txdone(struct iucv_path *, struct iucv_message *);
  97 static void iucv_callback_connack(struct iucv_path *, u8 *);
  98 static int iucv_callback_connreq(struct iucv_path *, u8 *, u8 *);
  99 static void iucv_callback_connrej(struct iucv_path *, u8 *);
 100 static void iucv_callback_shutdown(struct iucv_path *, u8 *);
 101
 102 static struct iucv_sock_list iucv_sk_list = {
 103         .lock = __RW_LOCK_UNLOCKED(iucv_sk_list.lock),
 104         .autobind_name = ATOMIC_INIT(0)
 105 };
 106
 107 static struct iucv_handler af_iucv_handler = {
 108         .path_pending     = iucv_callback_connreq,
 109         .path_complete    = iucv_callback_connack,
 110         .path_severed     = iucv_callback_connrej,
 111         .message_pending  = iucv_callback_rx,
 112         .message_complete = iucv_callback_txdone,
 113         .path_quiesced    = iucv_callback_shutdown,
 114 };
 115
 116 static inline void high_nmcpy(unsigned char *dst, char *src)
 117 {
 118        memcpy(dst, src, 8);
 119 }
 120
 121 static inline void low_nmcpy(unsigned char *dst, char *src)
 122 {
 123        memcpy(&dst[8], src, 8);
 124 }
 125
 126 /**
 127  * iucv_msg_length() - Returns the length of an iucv message.
 128  * @msg:        Pointer to struct iucv_message, MUST NOT be NULL
 129  *
 130  * The function returns the length of the specified iucv message @msg of data
 131  * stored in a buffer and of data stored in the parameter list (PRMDATA).
 132  *
 133  * For IUCV_IPRMDATA, AF_IUCV uses the following convention to transport socket
 134  * data:
 135  *      PRMDATA[0..6]   socket data (max 7 bytes);
 136  *      PRMDATA[7]      socket data length value (len is 0xff - PRMDATA[7])
 137  *
 138  * The socket data length is computed by subtracting the socket data length
 139  * value from 0xFF.
 140  * If the socket data len is greater 7, then PRMDATA can be used for special
 141  * notifications (see iucv_sock_shutdown); and further,
 142  * if the socket data len is > 7, the function returns 8.
 143  *
 144  * Use this function to allocate socket buffers to store iucv message data.
 145  */
 146 static inline size_t iucv_msg_length(struct iucv_message *msg)
 147 {
 148         size_t datalen;
 149
 150         if (msg->flags & IUCV_IPRMDATA) {
 151                 datalen = 0xff - msg->rmmsg[7];
 152                 return (datalen < 8) ? datalen : 8;
 153         }
 154         return msg->length;
 155 }
 156
 157 /**
 158  * iucv_sock_in_state() - check for specific states
 159  * @sk:         sock structure
 160  * @state:      first iucv sk state
 161  * @state:      second iucv sk state
 162  *
 163  * Returns true if the socket in either in the first or second state.
 164  */
 165 static int iucv_sock_in_state(struct sock *sk, int state, int state2)
 166 {
 167         return (sk->sk_state == state || sk->sk_state == state2);
 168 }
 169
 170 /**
 171  * iucv_below_msglim() - function to check if messages can be sent
 172  * @sk:         sock structure
 173  *
 174  * Returns true if the send queue length is lower than the message limit.
 175  * Always returns true if the socket is not connected (no iucv path for
 176  * checking the message limit).
 177  */
 178 static inline int iucv_below_msglim(struct sock *sk)
 179 {
 180         struct iucv_sock *iucv = iucv_sk(sk);
 181
 182         if (sk->sk_state != IUCV_CONNECTED)
 183                 return 1;
 184         if (iucv->transport == AF_IUCV_TRANS_IUCV)
 185                 return (skb_queue_len(&iucv->send_skb_q) < iucv->path->msglim);
 186         else
 187                 return ((atomic_read(&iucv->msg_sent) < iucv->msglimit_peer) &&
 188                         (atomic_read(&iucv->pendings) <= 0));
 189 }
 190
 191 /**
 192  * iucv_sock_wake_msglim() - Wake up thread waiting on msg limit
 193  */
 194 static void iucv_sock_wake_msglim(struct sock *sk)
 195 {
 196         struct socket_wq *wq;
 197
 198         rcu_read_lock();
 199         wq = rcu_dereference(sk->sk_wq);
 200         if (skwq_has_sleeper(wq))
 201                 wake_up_interruptible_all(&wq->wait);
 202         sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
 203         rcu_read_unlock();
 204 }
 205
 206 /**
 207  * afiucv_hs_send() - send a message through HiperSockets transport
 208  */
 209 static int afiucv_hs_send(struct iucv_message *imsg, struct sock *sock,
 210                    struct sk_buff *skb, u8 flags)
 211 {
 212         struct iucv_sock *iucv = iucv_sk(sock);
 213         struct af_iucv_trans_hdr *phs_hdr;
 214         struct sk_buff *nskb;
 215         int err, confirm_recv = 0;
 216
 217         phs_hdr = skb_push(skb, sizeof(*phs_hdr));
 218         memset(phs_hdr, 0, sizeof(*phs_hdr));
 219         skb_reset_network_header(skb);
 220
 221         phs_hdr->magic = ETH_P_AF_IUCV;
 222         phs_hdr->version = 1;
 223         phs_hdr->flags = flags;
 224         if (flags == AF_IUCV_FLAG_SYN)
 225                 phs_hdr->window = iucv->msglimit;
 226         else if ((flags == AF_IUCV_FLAG_WIN) || !flags) {
 227                 confirm_recv = atomic_read(&iucv->msg_recv);
 228                 phs_hdr->window = confirm_recv;
 229                 if (confirm_recv)
 230                         phs_hdr->flags = phs_hdr->flags | AF_IUCV_FLAG_WIN;
 231         }
 232         memcpy(phs_hdr->destUserID, iucv->dst_user_id, 8);
 233         memcpy(phs_hdr->destAppName, iucv->dst_name, 8);
 234         memcpy(phs_hdr->srcUserID, iucv->src_user_id, 8);
 235         memcpy(phs_hdr->srcAppName, iucv->src_name, 8);
 236         ASCEBC(phs_hdr->destUserID, sizeof(phs_hdr->destUserID));
 237         ASCEBC(phs_hdr->destAppName, sizeof(phs_hdr->destAppName));
 238         ASCEBC(phs_hdr->srcUserID, sizeof(phs_hdr->srcUserID));
 239         ASCEBC(phs_hdr->srcAppName, sizeof(phs_hdr->srcAppName));
 240         if (imsg)
 241                 memcpy(&phs_hdr->iucv_hdr, imsg, sizeof(struct iucv_message));
 242
 243         skb->dev = iucv->hs_dev;
 244         if (!skb->dev) {
 245                 err = -ENODEV;
 246                 goto err_free;
 247         }
 248
 249         dev_hard_header(skb, skb->dev, ETH_P_AF_IUCV, NULL, NULL, skb->len);
 250
 251         if (!(skb->dev->flags & IFF_UP) || !netif_carrier_ok(skb->dev)) {
 252                 err = -ENETDOWN;
 253                 goto err_free;
 254         }
 255         if (skb->len > skb->dev->mtu) {
 256                 if (sock->sk_type == SOCK_SEQPACKET) {
 257                         err = -EMSGSIZE;
 258                         goto err_free;
 259                 }
 260                 skb_trim(skb, skb->dev->mtu);
 261         }
 262         skb->protocol = cpu_to_be16(ETH_P_AF_IUCV);
 263
 264         __skb_header_release(skb);
 265         nskb = skb_clone(skb, GFP_ATOMIC);
 266         if (!nskb) {
 267                 err = -ENOMEM;
 268                 goto err_free;
 269         }
 270
 271         skb_queue_tail(&iucv->send_skb_q, nskb);
 272         err = dev_queue_xmit(skb);
 273         if (net_xmit_eval(err)) {
 274                 skb_unlink(nskb, &iucv->send_skb_q);
 275                 kfree_skb(nskb);
 276         } else {
 277                 atomic_sub(confirm_recv, &iucv->msg_recv);
 278                 WARN_ON(atomic_read(&iucv->msg_recv) < 0);
 279         }
 280         return net_xmit_eval(err);
 281
 282 err_free:
 283         kfree_skb(skb);
 284         return err;
 285 }
 286
 287 static struct sock *__iucv_get_sock_by_name(char *nm)
 288 {
 289         struct sock *sk;
 290
 291         sk_for_each(sk, &iucv_sk_list.head)
 292                 if (!memcmp(&iucv_sk(sk)->src_name, nm, 8))
 293                         return sk;
 294
 295         return NULL;
 296 }
 297
 298 static void iucv_sock_destruct(struct sock *sk)
 299 {
 300         skb_queue_purge(&sk->sk_receive_queue);
 301         skb_queue_purge(&sk->sk_error_queue);
 302
 303         sk_mem_reclaim(sk);
 304
 305         if (!sock_flag(sk, SOCK_DEAD)) {
 306                 pr_err("Attempt to release alive iucv socket %p\n", sk);
 307                 return;
 308         }
 309
 310         WARN_ON(atomic_read(&sk->sk_rmem_alloc));
 311         WARN_ON(refcount_read(&sk->sk_wmem_alloc));
 312         WARN_ON(sk->sk_wmem_queued);
 313         WARN_ON(sk->sk_forward_alloc);
 314 }
 315
 316 /* Cleanup Listen */
 317 static void iucv_sock_cleanup_listen(struct sock *parent)
 318 {
 319         struct sock *sk;
 320
 321         /* Close non-accepted connections */
 322         while ((sk = iucv_accept_dequeue(parent, NULL))) {
 323                 iucv_sock_close(sk);
 324                 iucv_sock_kill(sk);
 325         }
 326
 327         parent->sk_state = IUCV_CLOSED;
 328 }
 329
 330 static void iucv_sock_link(struct iucv_sock_list *l, struct sock *sk)
 331 {
 332         write_lock_bh(&l->lock);
 333         sk_add_node(sk, &l->head);
 334         write_unlock_bh(&l->lock);
 335 }
 336
 337 static void iucv_sock_unlink(struct iucv_sock_list *l, struct sock *sk)
 338 {
 339         write_lock_bh(&l->lock);
 340         sk_del_node_init(sk);
 341         write_unlock_bh(&l->lock);
 342 }
 343
 344 /* Kill socket (only if zapped and orphaned) */
 345 static void iucv_sock_kill(struct sock *sk)
 346 {
 347         if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket)
 348                 return;
 349
 350         iucv_sock_unlink(&iucv_sk_list, sk);
 351         sock_set_flag(sk, SOCK_DEAD);
 352         sock_put(sk);
 353 }
 354
 355 /* Terminate an IUCV path */
 356 static void iucv_sever_path(struct sock *sk, int with_user_data)
 357 {
 358         unsigned char user_data[16];
 359         struct iucv_sock *iucv = iucv_sk(sk);
 360         struct iucv_path *path = iucv->path;
 361
 362         if (iucv->path) {
 363                 iucv->path = NULL;
 364                 if (with_user_data) {
 365                         low_nmcpy(user_data, iucv->src_name);
 366                         high_nmcpy(user_data, iucv->dst_name);
 367                         ASCEBC(user_data, sizeof(user_data));
 368                         pr_iucv->path_sever(path, user_data);
 369                 } else
 370                         pr_iucv->path_sever(path, NULL);
 371                 iucv_path_free(path);
 372         }
 373 }
 374
 375 /* Send controlling flags through an IUCV socket for HIPER transport */
 376 static int iucv_send_ctrl(struct sock *sk, u8 flags)
 377 {
 378         struct iucv_sock *iucv = iucv_sk(sk);
 379         int err = 0;
 380         int blen;
 381         struct sk_buff *skb;
 382         u8 shutdown = 0;
 383
 384         blen = sizeof(struct af_iucv_trans_hdr) +
 385                LL_RESERVED_SPACE(iucv->hs_dev);
 386         if (sk->sk_shutdown & SEND_SHUTDOWN) {
 387                 /* controlling flags should be sent anyway */
 388                 shutdown = sk->sk_shutdown;
 389                 sk->sk_shutdown &= RCV_SHUTDOWN;
 390         }
 391         skb = sock_alloc_send_skb(sk, blen, 1, &err);
 392         if (skb) {
 393                 skb_reserve(skb, blen);
 394                 err = afiucv_hs_send(NULL, sk, skb, flags);
 395         }
 396         if (shutdown)
 397                 sk->sk_shutdown = shutdown;
 398         return err;
 399 }
 400
 401 /* Close an IUCV socket */
 402 static void iucv_sock_close(struct sock *sk)
 403 {
 404         struct iucv_sock *iucv = iucv_sk(sk);
 405         unsigned long timeo;
 406         int err = 0;
 407
 408         lock_sock(sk);
 409
 410         switch (sk->sk_state) {
 411         case IUCV_LISTEN:
 412                 iucv_sock_cleanup_listen(sk);
 413                 break;
 414
 415         case IUCV_CONNECTED:
 416                 if (iucv->transport == AF_IUCV_TRANS_HIPER) {
 417                         err = iucv_send_ctrl(sk, AF_IUCV_FLAG_FIN);
 418                         sk->sk_state = IUCV_DISCONN;
 419                         sk->sk_state_change(sk);
 420                 }
 421                 fallthrough;
 422
 423         case IUCV_DISCONN:
 424                 sk->sk_state = IUCV_CLOSING;
 425                 sk->sk_state_change(sk);
 426
 427                 if (!err && !skb_queue_empty(&iucv->send_skb_q)) {
 428                         if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime)
 429                                 timeo = sk->sk_lingertime;
 430                         else
 431                                 timeo = IUCV_DISCONN_TIMEOUT;
 432                         iucv_sock_wait(sk,
 433                                         iucv_sock_in_state(sk, IUCV_CLOSED, 0),
 434                                         timeo);
 435                 }
 436                 fallthrough;
 437
 438         case IUCV_CLOSING:
 439                 sk->sk_state = IUCV_CLOSED;
 440                 sk->sk_state_change(sk);
 441
 442                 sk->sk_err = ECONNRESET;
 443                 sk->sk_state_change(sk);
 444
 445                 skb_queue_purge(&iucv->send_skb_q);
 446                 skb_queue_purge(&iucv->backlog_skb_q);
 447                 fallthrough;
 448
 449         default:
 450                 iucv_sever_path(sk, 1);
 451         }
 452
 453         if (iucv->hs_dev) {
 454                 dev_put(iucv->hs_dev);
 455                 iucv->hs_dev = NULL;
 456                 sk->sk_bound_dev_if = 0;
 457         }
 458
 459         /* mark socket for deletion by iucv_sock_kill() */
 460         sock_set_flag(sk, SOCK_ZAPPED);
 461
 462         release_sock(sk);
 463 }
 464
 465 static void iucv_sock_init(struct sock *sk, struct sock *parent)
 466 {
 467         if (parent) {
 468                 sk->sk_type = parent->sk_type;
 469                 security_sk_clone(parent, sk);
 470         }
 471 }
 472
 473 static struct sock *iucv_sock_alloc(struct socket *sock, int proto, gfp_t prio, int kern)
 474 {
 475         struct sock *sk;
 476         struct iucv_sock *iucv;
 477
 478         sk = sk_alloc(&init_net, PF_IUCV, prio, &iucv_proto, kern);
 479         if (!sk)
 480                 return NULL;
 481         iucv = iucv_sk(sk);
 482
 483         sock_init_data(sock, sk);
 484         INIT_LIST_HEAD(&iucv->accept_q);
 485         spin_lock_init(&iucv->accept_q_lock);
 486         skb_queue_head_init(&iucv->send_skb_q);
 487         INIT_LIST_HEAD(&iucv->message_q.list);
 488         spin_lock_init(&iucv->message_q.lock);
 489         skb_queue_head_init(&iucv->backlog_skb_q);
 490         iucv->send_tag = 0;
 491         atomic_set(&iucv->pendings, 0);
 492         iucv->flags = 0;
 493         iucv->msglimit = 0;
 494         atomic_set(&iucv->msg_sent, 0);
 495         atomic_set(&iucv->msg_recv, 0);
 496         iucv->path = NULL;
 497         iucv->sk_txnotify = afiucv_hs_callback_txnotify;
 498         memset(&iucv->src_user_id , 0, 32);
 499         if (pr_iucv)
 500                 iucv->transport = AF_IUCV_TRANS_IUCV;
 501         else
 502                 iucv->transport = AF_IUCV_TRANS_HIPER;
 503
 504         sk->sk_destruct = iucv_sock_destruct;
 505         sk->sk_sndtimeo = IUCV_CONN_TIMEOUT;
 506
 507         sock_reset_flag(sk, SOCK_ZAPPED);
 508
 509         sk->sk_protocol = proto;
 510         sk->sk_state    = IUCV_OPEN;
 511
 512         iucv_sock_link(&iucv_sk_list, sk);
 513         return sk;
 514 }
 515
 516 static void iucv_accept_enqueue(struct sock *parent, struct sock *sk)
 517 {
 518         unsigned long flags;
 519         struct iucv_sock *par = iucv_sk(parent);
 520
 521         sock_hold(sk);
 522         spin_lock_irqsave(&par->accept_q_lock, flags);
 523         list_add_tail(&iucv_sk(sk)->accept_q, &par->accept_q);
 524         spin_unlock_irqrestore(&par->accept_q_lock, flags);
 525         iucv_sk(sk)->parent = parent;
 526         sk_acceptq_added(parent);
 527 }
 528
 529 static void iucv_accept_unlink(struct sock *sk)
 530 {
 531         unsigned long flags;
 532         struct iucv_sock *par = iucv_sk(iucv_sk(sk)->parent);
 533
 534         spin_lock_irqsave(&par->accept_q_lock, flags);
 535         list_del_init(&iucv_sk(sk)->accept_q);
 536         spin_unlock_irqrestore(&par->accept_q_lock, flags);
 537         sk_acceptq_removed(iucv_sk(sk)->parent);
 538         iucv_sk(sk)->parent = NULL;
 539         sock_put(sk);
 540 }
 541
 542 static struct sock *iucv_accept_dequeue(struct sock *parent,
 543                                         struct socket *newsock)
 544 {
 545         struct iucv_sock *isk, *n;
 546         struct sock *sk;
 547
 548         list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
 549                 sk = (struct sock *) isk;
 550                 lock_sock(sk);
 551
 552                 if (sk->sk_state == IUCV_CLOSED) {
 553                         iucv_accept_unlink(sk);
 554                         release_sock(sk);
 555                         continue;
 556                 }
 557
 558                 if (sk->sk_state == IUCV_CONNECTED ||
 559                     sk->sk_state == IUCV_DISCONN ||
 560                     !newsock) {
 561                         iucv_accept_unlink(sk);
 562                         if (newsock)
 563                                 sock_graft(sk, newsock);
 564
 565                         release_sock(sk);
 566                         return sk;
 567                 }
 568
 569                 release_sock(sk);
 570         }
 571         return NULL;
 572 }
 573
 574 static void __iucv_auto_name(struct iucv_sock *iucv)
 575 {
 576         char name[12];
 577
 578         sprintf(name, "%08x", atomic_inc_return(&iucv_sk_list.autobind_name));
 579         while (__iucv_get_sock_by_name(name)) {
 580                 sprintf(name, "%08x",
 581                         atomic_inc_return(&iucv_sk_list.autobind_name));
 582         }
 583         memcpy(iucv->src_name, name, 8);
 584 }
 585
 586 /* Bind an unbound socket */
 587 static int iucv_sock_bind(struct socket *sock, struct sockaddr *addr,
 588                           int addr_len)
 589 {
 590         DECLARE_SOCKADDR(struct sockaddr_iucv *, sa, addr);
 591         char uid[sizeof(sa->siucv_user_id)];
 592         struct sock *sk = sock->sk;
 593         struct iucv_sock *iucv;
 594         int err = 0;
 595         struct net_device *dev;
 596
 597         /* Verify the input sockaddr */
 598         if (addr_len < sizeof(struct sockaddr_iucv) ||
 599             addr->sa_family != AF_IUCV)
 600                 return -EINVAL;
 601
 602         lock_sock(sk);
 603         if (sk->sk_state != IUCV_OPEN) {
 604                 err = -EBADFD;
 605                 goto done;
 606         }
 607
 608         write_lock_bh(&iucv_sk_list.lock);
 609
 610         iucv = iucv_sk(sk);
 611         if (__iucv_get_sock_by_name(sa->siucv_name)) {
 612                 err = -EADDRINUSE;
 613                 goto done_unlock;
 614         }
 615         if (iucv->path)
 616                 goto done_unlock;
 617
 618         /* Bind the socket */
 619         if (pr_iucv)
 620                 if (!memcmp(sa->siucv_user_id, iucv_userid, 8))
 621                         goto vm_bind; /* VM IUCV transport */
 622
 623         /* try hiper transport */
 624         memcpy(uid, sa->siucv_user_id, sizeof(uid));
 625         ASCEBC(uid, 8);
 626         rcu_read_lock();
 627         for_each_netdev_rcu(&init_net, dev) {
 628                 if (!memcmp(dev->perm_addr, uid, 8)) {
 629                         memcpy(iucv->src_user_id, sa->siucv_user_id, 8);
 630                         /* Check for unitialized siucv_name */
 631                         if (strncmp(sa->siucv_name, "        ", 8) == 0)
 632                                 __iucv_auto_name(iucv);
 633                         else
 634                                 memcpy(iucv->src_name, sa->siucv_name, 8);
 635                         sk->sk_bound_dev_if = dev->ifindex;
 636                         iucv->hs_dev = dev;
 637                         dev_hold(dev);
 638                         sk->sk_state = IUCV_BOUND;
 639                         iucv->transport = AF_IUCV_TRANS_HIPER;
 640                         if (!iucv->msglimit)
 641                                 iucv->msglimit = IUCV_HIPER_MSGLIM_DEFAULT;
 642                         rcu_read_unlock();
 643                         goto done_unlock;
 644                 }
 645         }
 646         rcu_read_unlock();
 647 vm_bind:
 648         if (pr_iucv) {
 649                 /* use local userid for backward compat */
 650                 memcpy(iucv->src_name, sa->siucv_name, 8);
 651                 memcpy(iucv->src_user_id, iucv_userid, 8);
 652                 sk->sk_state = IUCV_BOUND;
 653                 iucv->transport = AF_IUCV_TRANS_IUCV;
 654                 sk->sk_allocation |= GFP_DMA;
 655                 if (!iucv->msglimit)
 656                         iucv->msglimit = IUCV_QUEUELEN_DEFAULT;
 657                 goto done_unlock;
 658         }
 659         /* found no dev to bind */
 660         err = -ENODEV;
 661 done_unlock:
 662         /* Release the socket list lock */
 663         write_unlock_bh(&iucv_sk_list.lock);
 664 done:
 665         release_sock(sk);
 666         return err;
 667 }
 668
 669 /* Automatically bind an unbound socket */
 670 static int iucv_sock_autobind(struct sock *sk)
 671 {
 672         struct iucv_sock *iucv = iucv_sk(sk);
 673         int err = 0;
 674
 675         if (unlikely(!pr_iucv))
 676                 return -EPROTO;
 677
 678         memcpy(iucv->src_user_id, iucv_userid, 8);
 679         iucv->transport = AF_IUCV_TRANS_IUCV;
 680         sk->sk_allocation |= GFP_DMA;
 681
 682         write_lock_bh(&iucv_sk_list.lock);
 683         __iucv_auto_name(iucv);
 684         write_unlock_bh(&iucv_sk_list.lock);
 685
 686         if (!iucv->msglimit)
 687                 iucv->msglimit = IUCV_QUEUELEN_DEFAULT;
 688
 689         return err;
 690 }
 691
 692 static int afiucv_path_connect(struct socket *sock, struct sockaddr *addr)
 693 {
 694         DECLARE_SOCKADDR(struct sockaddr_iucv *, sa, addr);
 695         struct sock *sk = sock->sk;
 696         struct iucv_sock *iucv = iucv_sk(sk);
 697         unsigned char user_data[16];
 698         int err;
 699
 700         high_nmcpy(user_data, sa->siucv_name);
 701         low_nmcpy(user_data, iucv->src_name);
 702         ASCEBC(user_data, sizeof(user_data));
 703
 704         /* Create path. */
 705         iucv->path = iucv_path_alloc(iucv->msglimit,
 706                                      IUCV_IPRMDATA, GFP_KERNEL);
 707         if (!iucv->path) {
 708                 err = -ENOMEM;
 709                 goto done;
 710         }
 711         err = pr_iucv->path_connect(iucv->path, &af_iucv_handler,
 712                                     sa->siucv_user_id, NULL, user_data,
 713                                     sk);
 714         if (err) {
 715                 iucv_path_free(iucv->path);
 716                 iucv->path = NULL;
 717                 switch (err) {
 718                 case 0x0b:      /* Target communicator is not logged on */
 719                         err = -ENETUNREACH;
 720                         break;
 721                 case 0x0d:      /* Max connections for this guest exceeded */
 722                 case 0x0e:      /* Max connections for target guest exceeded */
 723                         err = -EAGAIN;
 724                         break;
 725                 case 0x0f:      /* Missing IUCV authorization */
 726                         err = -EACCES;
 727                         break;
 728                 default:
 729                         err = -ECONNREFUSED;
 730                         break;
 731                 }
 732         }
 733 done:
 734         return err;
 735 }
 736
 737 /* Connect an unconnected socket */
 738 static int iucv_sock_connect(struct socket *sock, struct sockaddr *addr,
 739                              int alen, int flags)
 740 {
 741         DECLARE_SOCKADDR(struct sockaddr_iucv *, sa, addr);
 742         struct sock *sk = sock->sk;
 743         struct iucv_sock *iucv = iucv_sk(sk);
 744         int err;
 745
 746         if (alen < sizeof(struct sockaddr_iucv) || addr->sa_family != AF_IUCV)
 747                 return -EINVAL;
 748
 749         if (sk->sk_state != IUCV_OPEN && sk->sk_state != IUCV_BOUND)
 750                 return -EBADFD;
 751
 752         if (sk->sk_state == IUCV_OPEN &&
 753             iucv->transport == AF_IUCV_TRANS_HIPER)
 754                 return -EBADFD; /* explicit bind required */
 755
 756         if (sk->sk_type != SOCK_STREAM && sk->sk_type != SOCK_SEQPACKET)
 757                 return -EINVAL;
 758
 759         if (sk->sk_state == IUCV_OPEN) {
 760                 err = iucv_sock_autobind(sk);
 761                 if (unlikely(err))
 762                         return err;
 763         }
 764
 765         lock_sock(sk);
 766
 767         /* Set the destination information */
 768         memcpy(iucv->dst_user_id, sa->siucv_user_id, 8);
 769         memcpy(iucv->dst_name, sa->siucv_name, 8);
 770
 771         if (iucv->transport == AF_IUCV_TRANS_HIPER)
 772                 err = iucv_send_ctrl(sock->sk, AF_IUCV_FLAG_SYN);
 773         else
 774                 err = afiucv_path_connect(sock, addr);
 775         if (err)
 776                 goto done;
 777
 778         if (sk->sk_state != IUCV_CONNECTED)
 779                 err = iucv_sock_wait(sk, iucv_sock_in_state(sk, IUCV_CONNECTED,
 780                                                             IUCV_DISCONN),
 781                                      sock_sndtimeo(sk, flags & O_NONBLOCK));
 782
 783         if (sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_CLOSED)
 784                 err = -ECONNREFUSED;
 785
 786         if (err && iucv->transport == AF_IUCV_TRANS_IUCV)
 787                 iucv_sever_path(sk, 0);
 788
 789 done:
 790         release_sock(sk);
 791         return err;
 792 }
 793
 794 /* Move a socket into listening state. */
 795 static int iucv_sock_listen(struct socket *sock, int backlog)
 796 {
 797         struct sock *sk = sock->sk;
 798         int err;
 799
 800         lock_sock(sk);
 801
 802         err = -EINVAL;
 803         if (sk->sk_state != IUCV_BOUND)
 804                 goto done;
 805
 806         if (sock->type != SOCK_STREAM && sock->type != SOCK_SEQPACKET)
 807                 goto done;
 808
 809         sk->sk_max_ack_backlog = backlog;
 810         sk->sk_ack_backlog = 0;
 811         sk->sk_state = IUCV_LISTEN;
 812         err = 0;
 813
 814 done:
 815         release_sock(sk);
 816         return err;
 817 }
 818
 819 /* Accept a pending connection */
 820 static int iucv_sock_accept(struct socket *sock, struct socket *newsock,
 821                             int flags, bool kern)
 822 {
 823         DECLARE_WAITQUEUE(wait, current);
 824         struct sock *sk = sock->sk, *nsk;
 825         long timeo;
 826         int err = 0;
 827
 828         lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
 829
 830         if (sk->sk_state != IUCV_LISTEN) {
 831                 err = -EBADFD;
 832                 goto done;
 833         }
 834
 835         timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
 836
 837         /* Wait for an incoming connection */
 838         add_wait_queue_exclusive(sk_sleep(sk), &wait);
 839         while (!(nsk = iucv_accept_dequeue(sk, newsock))) {
 840                 set_current_state(TASK_INTERRUPTIBLE);
 841                 if (!timeo) {
 842                         err = -EAGAIN;
 843                         break;
 844                 }
 845
 846                 release_sock(sk);
 847                 timeo = schedule_timeout(timeo);
 848                 lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
 849
 850                 if (sk->sk_state != IUCV_LISTEN) {
 851                         err = -EBADFD;
 852                         break;
 853                 }
 854
 855                 if (signal_pending(current)) {
 856                         err = sock_intr_errno(timeo);
 857                         break;
 858                 }
 859         }
 860
 861         set_current_state(TASK_RUNNING);
 862         remove_wait_queue(sk_sleep(sk), &wait);
 863
 864         if (err)
 865                 goto done;
 866
 867         newsock->state = SS_CONNECTED;
 868
 869 done:
 870         release_sock(sk);
 871         return err;
 872 }
 873
 874 static int iucv_sock_getname(struct socket *sock, struct sockaddr *addr,
 875                              int peer)
 876 {
 877         DECLARE_SOCKADDR(struct sockaddr_iucv *, siucv, addr);
 878         struct sock *sk = sock->sk;
 879         struct iucv_sock *iucv = iucv_sk(sk);
 880
 881         addr->sa_family = AF_IUCV;
 882
 883         if (peer) {
 884                 memcpy(siucv->siucv_user_id, iucv->dst_user_id, 8);
 885                 memcpy(siucv->siucv_name, iucv->dst_name, 8);
 886         } else {
 887                 memcpy(siucv->siucv_user_id, iucv->src_user_id, 8);
 888                 memcpy(siucv->siucv_name, iucv->src_name, 8);
 889         }
 890         memset(&siucv->siucv_port, 0, sizeof(siucv->siucv_port));
 891         memset(&siucv->siucv_addr, 0, sizeof(siucv->siucv_addr));
 892         memset(&siucv->siucv_nodeid, 0, sizeof(siucv->siucv_nodeid));
 893
 894         return sizeof(struct sockaddr_iucv);
 895 }
 896
 897 /**
 898  * iucv_send_iprm() - Send socket data in parameter list of an iucv message.
 899  * @path:       IUCV path
 900  * @msg:        Pointer to a struct iucv_message
 901  * @skb:        The socket data to send, skb->len MUST BE <= 7
 902  *
 903  * Send the socket data in the parameter list in the iucv message
 904  * (IUCV_IPRMDATA). The socket data is stored at index 0 to 6 in the parameter
 905  * list and the socket data len at index 7 (last byte).
 906  * See also iucv_msg_length().
 907  *
 908  * Returns the error code from the iucv_message_send() call.
 909  */
 910 static int iucv_send_iprm(struct iucv_path *path, struct iucv_message *msg,
 911                           struct sk_buff *skb)
 912 {
 913         u8 prmdata[8];
 914
 915         memcpy(prmdata, (void *) skb->data, skb->len);
 916         prmdata[7] = 0xff - (u8) skb->len;
 917         return pr_iucv->message_send(path, msg, IUCV_IPRMDATA, 0,
 918                                  (void *) prmdata, 8);
 919 }
 920
 921 static int iucv_sock_sendmsg(struct socket *sock, struct msghdr *msg,
 922                              size_t len)
 923 {
 924         struct sock *sk = sock->sk;
 925         struct iucv_sock *iucv = iucv_sk(sk);
 926         size_t headroom = 0;
 927         size_t linear;
 928         struct sk_buff *skb;
 929         struct iucv_message txmsg = {0};
 930         struct cmsghdr *cmsg;
 931         int cmsg_done;
 932         long timeo;
 933         char user_id[9];
 934         char appl_id[9];
 935         int err;
 936         int noblock = msg->msg_flags & MSG_DONTWAIT;
 937
 938         err = sock_error(sk);
 939         if (err)
 940                 return err;
 941
 942         if (msg->msg_flags & MSG_OOB)
 943                 return -EOPNOTSUPP;
 944
 945         /* SOCK_SEQPACKET: we do not support segmented records */
 946         if (sk->sk_type == SOCK_SEQPACKET && !(msg->msg_flags & MSG_EOR))
 947                 return -EOPNOTSUPP;
 948
 949         lock_sock(sk);
 950
 951         if (sk->sk_shutdown & SEND_SHUTDOWN) {
 952                 err = -EPIPE;
 953                 goto out;
 954         }
 955
 956         /* Return if the socket is not in connected state */
 957         if (sk->sk_state != IUCV_CONNECTED) {
 958                 err = -ENOTCONN;
 959                 goto out;
 960         }
 961
 962         /* initialize defaults */
 963         cmsg_done   = 0;        /* check for duplicate headers */
 964
 965         /* iterate over control messages */
 966         for_each_cmsghdr(cmsg, msg) {
 967                 if (!CMSG_OK(msg, cmsg)) {
 968                         err = -EINVAL;
 969                         goto out;
 970                 }
 971
 972                 if (cmsg->cmsg_level != SOL_IUCV)
 973                         continue;
 974
 975                 if (cmsg->cmsg_type & cmsg_done) {
 976                         err = -EINVAL;
 977                         goto out;
 978                 }
 979                 cmsg_done |= cmsg->cmsg_type;
 980
 981                 switch (cmsg->cmsg_type) {
 982                 case SCM_IUCV_TRGCLS:
 983                         if (cmsg->cmsg_len != CMSG_LEN(TRGCLS_SIZE)) {
 984                                 err = -EINVAL;
 985                                 goto out;
 986                         }
 987
 988                         /* set iucv message target class */
 989                         memcpy(&txmsg.class,
 990                                 (void *) CMSG_DATA(cmsg), TRGCLS_SIZE);
 991
 992                         break;
 993
 994                 default:
 995                         err = -EINVAL;
 996                         goto out;
 997                 }
 998         }
 999
1000         /* allocate one skb for each iucv message:
1001          * this is fine for SOCK_SEQPACKET (unless we want to support
1002          * segmented records using the MSG_EOR flag), but
1003          * for SOCK_STREAM we might want to improve it in future */
1004         if (iucv->transport == AF_IUCV_TRANS_HIPER) {
1005                 headroom = sizeof(struct af_iucv_trans_hdr) +
1006                            LL_RESERVED_SPACE(iucv->hs_dev);
1007                 linear = len;
1008         } else {
1009                 if (len < PAGE_SIZE) {
1010                         linear = len;
1011                 } else {
1012                         /* In nonlinear "classic" iucv skb,
1013                          * reserve space for iucv_array
1014                          */
1015                         headroom = sizeof(struct iucv_array) *
1016                                    (MAX_SKB_FRAGS + 1);
1017                         linear = PAGE_SIZE - headroom;
1018                 }
1019         }
1020         skb = sock_alloc_send_pskb(sk, headroom + linear, len - linear,
1021                                    noblock, &err, 0);
1022         if (!skb)
1023                 goto out;
1024         if (headroom)
1025                 skb_reserve(skb, headroom);
1026         skb_put(skb, linear);
1027         skb->len = len;
1028         skb->data_len = len - linear;
1029         err = skb_copy_datagram_from_iter(skb, 0, &msg->msg_iter, len);
1030         if (err)
1031                 goto fail;
1032
1033         /* wait if outstanding messages for iucv path has reached */
1034         timeo = sock_sndtimeo(sk, noblock);
1035         err = iucv_sock_wait(sk, iucv_below_msglim(sk), timeo);
1036         if (err)
1037                 goto fail;
1038
1039         /* return -ECONNRESET if the socket is no longer connected */
1040         if (sk->sk_state != IUCV_CONNECTED) {
1041                 err = -ECONNRESET;
1042                 goto fail;
1043         }
1044
1045         /* increment and save iucv message tag for msg_completion cbk */
1046         txmsg.tag = iucv->send_tag++;
1047         IUCV_SKB_CB(skb)->tag = txmsg.tag;
1048
1049         if (iucv->transport == AF_IUCV_TRANS_HIPER) {
1050                 atomic_inc(&iucv->msg_sent);
1051                 err = afiucv_hs_send(&txmsg, sk, skb, 0);
1052                 if (err) {
1053                         atomic_dec(&iucv->msg_sent);
1054                         goto out;
1055                 }
1056         } else { /* Classic VM IUCV transport */
1057                 skb_queue_tail(&iucv->send_skb_q, skb);
1058
1059                 if (((iucv->path->flags & IUCV_IPRMDATA) & iucv->flags) &&
1060                     skb->len <= 7) {
1061                         err = iucv_send_iprm(iucv->path, &txmsg, skb);
1062
1063                         /* on success: there is no message_complete callback */
1064                         /* for an IPRMDATA msg; remove skb from send queue   */
1065                         if (err == 0) {
1066                                 skb_unlink(skb, &iucv->send_skb_q);
1067                                 kfree_skb(skb);
1068                         }
1069
1070                         /* this error should never happen since the     */
1071                         /* IUCV_IPRMDATA path flag is set... sever path */
1072                         if (err == 0x15) {
1073                                 pr_iucv->path_sever(iucv->path, NULL);
1074                                 skb_unlink(skb, &iucv->send_skb_q);
1075                                 err = -EPIPE;
1076                                 goto fail;
1077                         }
1078                 } else if (skb_is_nonlinear(skb)) {
1079                         struct iucv_array *iba = (struct iucv_array *)skb->head;
1080                         int i;
1081
1082                         /* skip iucv_array lying in the headroom */
1083                         iba[0].address = (u32)(addr_t)skb->data;
1084                         iba[0].length = (u32)skb_headlen(skb);
1085                         for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1086                                 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
1087
1088                                 iba[i + 1].address =
1089                                         (u32)(addr_t)skb_frag_address(frag);
1090                                 iba[i + 1].length = (u32)skb_frag_size(frag);
1091                         }
1092                         err = pr_iucv->message_send(iucv->path, &txmsg,
1093                                                     IUCV_IPBUFLST, 0,
1094                                                     (void *)iba, skb->len);
1095                 } else { /* non-IPRM Linear skb */
1096                         err = pr_iucv->message_send(iucv->path, &txmsg,
1097                                         0, 0, (void *)skb->data, skb->len);
1098                 }
1099                 if (err) {
1100                         if (err == 3) {
1101                                 user_id[8] = 0;
1102                                 memcpy(user_id, iucv->dst_user_id, 8);
1103                                 appl_id[8] = 0;
1104                                 memcpy(appl_id, iucv->dst_name, 8);
1105                                 pr_err(
1106                 "Application %s on z/VM guest %s exceeds message limit\n",
1107                                         appl_id, user_id);
1108                                 err = -EAGAIN;
1109                         } else {
1110                                 err = -EPIPE;
1111                         }
1112                         skb_unlink(skb, &iucv->send_skb_q);
1113                         goto fail;
1114                 }
1115         }
1116
1117         release_sock(sk);
1118         return len;
1119
1120 fail:
1121         kfree_skb(skb);
1122 out:
1123         release_sock(sk);
1124         return err;
1125 }
1126
1127 static struct sk_buff *alloc_iucv_recv_skb(unsigned long len)
1128 {
1129         size_t headroom, linear;
1130         struct sk_buff *skb;
1131         int err;
1132
1133         if (len < PAGE_SIZE) {
1134                 headroom = 0;
1135                 linear = len;
1136         } else {
1137                 headroom = sizeof(struct iucv_array) * (MAX_SKB_FRAGS + 1);
1138                 linear = PAGE_SIZE - headroom;
1139         }
1140         skb = alloc_skb_with_frags(headroom + linear, len - linear,
1141                                    0, &err, GFP_ATOMIC | GFP_DMA);
1142         WARN_ONCE(!skb,
1143                   "alloc of recv iucv skb len=%lu failed with errcode=%d\n",
1144                   len, err);
1145         if (skb) {
1146                 if (headroom)
1147                         skb_reserve(skb, headroom);
1148                 skb_put(skb, linear);
1149                 skb->len = len;
1150                 skb->data_len = len - linear;
1151         }
1152         return skb;
1153 }
1154
1155 /* iucv_process_message() - Receive a single outstanding IUCV message
1156  *
1157  * Locking: must be called with message_q.lock held
1158  */
1159 static void iucv_process_message(struct sock *sk, struct sk_buff *skb,
1160                                  struct iucv_path *path,
1161                                  struct iucv_message *msg)
1162 {
1163         int rc;
1164         unsigned int len;
1165
1166         len = iucv_msg_length(msg);
1167
1168         /* store msg target class in the second 4 bytes of skb ctrl buffer */
1169         /* Note: the first 4 bytes are reserved for msg tag */
1170         IUCV_SKB_CB(skb)->class = msg->class;
1171
1172         /* check for special IPRM messages (e.g. iucv_sock_shutdown) */
1173         if ((msg->flags & IUCV_IPRMDATA) && len > 7) {
1174                 if (memcmp(msg->rmmsg, iprm_shutdown, 8) == 0) {
1175                         skb->data = NULL;
1176                         skb->len = 0;
1177                 }
1178         } else {
1179                 if (skb_is_nonlinear(skb)) {
1180                         struct iucv_array *iba = (struct iucv_array *)skb->head;
1181                         int i;
1182
1183                         iba[0].address = (u32)(addr_t)skb->data;
1184                         iba[0].length = (u32)skb_headlen(skb);
1185                         for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1186                                 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
1187
1188                                 iba[i + 1].address =
1189                                         (u32)(addr_t)skb_frag_address(frag);
1190                                 iba[i + 1].length = (u32)skb_frag_size(frag);
1191                         }
1192                         rc = pr_iucv->message_receive(path, msg,
1193                                               IUCV_IPBUFLST,
1194                                               (void *)iba, len, NULL);
1195                 } else {
1196                         rc = pr_iucv->message_receive(path, msg,
1197                                               msg->flags & IUCV_IPRMDATA,
1198                                               skb->data, len, NULL);
1199                 }
1200                 if (rc) {
1201                         kfree_skb(skb);
1202                         return;
1203                 }
1204                 WARN_ON_ONCE(skb->len != len);
1205         }
1206
1207         IUCV_SKB_CB(skb)->offset = 0;
1208         if (sk_filter(sk, skb)) {
1209                 atomic_inc(&sk->sk_drops);      /* skb rejected by filter */
1210                 kfree_skb(skb);
1211                 return;
1212         }
1213         if (__sock_queue_rcv_skb(sk, skb))      /* handle rcv queue full */
1214                 skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, skb);
1215 }
1216
1217 /* iucv_process_message_q() - Process outstanding IUCV messages
1218  *
1219  * Locking: must be called with message_q.lock held
1220  */
1221 static void iucv_process_message_q(struct sock *sk)
1222 {
1223         struct iucv_sock *iucv = iucv_sk(sk);
1224         struct sk_buff *skb;
1225         struct sock_msg_q *p, *n;
1226
1227         list_for_each_entry_safe(p, n, &iucv->message_q.list, list) {
1228                 skb = alloc_iucv_recv_skb(iucv_msg_length(&p->msg));
1229                 if (!skb)
1230                         break;
1231                 iucv_process_message(sk, skb, p->path, &p->msg);
1232                 list_del(&p->list);
1233                 kfree(p);
1234                 if (!skb_queue_empty(&iucv->backlog_skb_q))
1235                         break;
1236         }
1237 }
1238
1239 static int iucv_sock_recvmsg(struct socket *sock, struct msghdr *msg,
1240                              size_t len, int flags)
1241 {
1242         int noblock = flags & MSG_DONTWAIT;
1243         struct sock *sk = sock->sk;
1244         struct iucv_sock *iucv = iucv_sk(sk);
1245         unsigned int copied, rlen;
1246         struct sk_buff *skb, *rskb, *cskb;
1247         int err = 0;
1248         u32 offset;
1249
1250         if ((sk->sk_state == IUCV_DISCONN) &&
1251             skb_queue_empty(&iucv->backlog_skb_q) &&
1252             skb_queue_empty(&sk->sk_receive_queue) &&
1253             list_empty(&iucv->message_q.list))
1254                 return 0;
1255
1256         if (flags & (MSG_OOB))
1257                 return -EOPNOTSUPP;
1258
1259         /* receive/dequeue next skb:
1260          * the function understands MSG_PEEK and, thus, does not dequeue skb */
1261         skb = skb_recv_datagram(sk, flags, noblock, &err);
1262         if (!skb) {
1263                 if (sk->sk_shutdown & RCV_SHUTDOWN)
1264                         return 0;
1265                 return err;
1266         }
1267
1268         offset = IUCV_SKB_CB(skb)->offset;
1269         rlen   = skb->len - offset;             /* real length of skb */
1270         copied = min_t(unsigned int, rlen, len);
1271         if (!rlen)
1272                 sk->sk_shutdown = sk->sk_shutdown | RCV_SHUTDOWN;
1273
1274         cskb = skb;
1275         if (skb_copy_datagram_msg(cskb, offset, msg, copied)) {
1276                 if (!(flags & MSG_PEEK))
1277                         skb_queue_head(&sk->sk_receive_queue, skb);
1278                 return -EFAULT;
1279         }
1280
1281         /* SOCK_SEQPACKET: set MSG_TRUNC if recv buf size is too small */
1282         if (sk->sk_type == SOCK_SEQPACKET) {
1283                 if (copied < rlen)
1284                         msg->msg_flags |= MSG_TRUNC;
1285                 /* each iucv message contains a complete record */
1286                 msg->msg_flags |= MSG_EOR;
1287         }
1288
1289         /* create control message to store iucv msg target class:
1290          * get the trgcls from the control buffer of the skb due to
1291          * fragmentation of original iucv message. */
1292         err = put_cmsg(msg, SOL_IUCV, SCM_IUCV_TRGCLS,
1293                        sizeof(IUCV_SKB_CB(skb)->class),
1294                        (void *)&IUCV_SKB_CB(skb)->class);
1295         if (err) {
1296                 if (!(flags & MSG_PEEK))
1297                         skb_queue_head(&sk->sk_receive_queue, skb);
1298                 return err;
1299         }
1300
1301         /* Mark read part of skb as used */
1302         if (!(flags & MSG_PEEK)) {
1303
1304                 /* SOCK_STREAM: re-queue skb if it contains unreceived data */
1305                 if (sk->sk_type == SOCK_STREAM) {
1306                         if (copied < rlen) {
1307                                 IUCV_SKB_CB(skb)->offset = offset + copied;
1308                                 skb_queue_head(&sk->sk_receive_queue, skb);
1309                                 goto done;
1310                         }
1311                 }
1312
1313                 kfree_skb(skb);
1314                 if (iucv->transport == AF_IUCV_TRANS_HIPER) {
1315                         atomic_inc(&iucv->msg_recv);
1316                         if (atomic_read(&iucv->msg_recv) > iucv->msglimit) {
1317                                 WARN_ON(1);
1318                                 iucv_sock_close(sk);
1319                                 return -EFAULT;
1320                         }
1321                 }
1322
1323                 /* Queue backlog skbs */
1324                 spin_lock_bh(&iucv->message_q.lock);
1325                 rskb = skb_dequeue(&iucv->backlog_skb_q);
1326                 while (rskb) {
1327                         IUCV_SKB_CB(rskb)->offset = 0;
1328                         if (__sock_queue_rcv_skb(sk, rskb)) {
1329                                 /* handle rcv queue full */
1330                                 skb_queue_head(&iucv->backlog_skb_q,
1331                                                 rskb);
1332                                 break;
1333                         }
1334                         rskb = skb_dequeue(&iucv->backlog_skb_q);
1335                 }
1336                 if (skb_queue_empty(&iucv->backlog_skb_q)) {
1337                         if (!list_empty(&iucv->message_q.list))
1338                                 iucv_process_message_q(sk);
1339                         if (atomic_read(&iucv->msg_recv) >=
1340                                                         iucv->msglimit / 2) {
1341                                 err = iucv_send_ctrl(sk, AF_IUCV_FLAG_WIN);
1342                                 if (err) {
1343                                         sk->sk_state = IUCV_DISCONN;
1344                                         sk->sk_state_change(sk);
1345                                 }
1346                         }
1347                 }
1348                 spin_unlock_bh(&iucv->message_q.lock);
1349         }
1350
1351 done:
1352         /* SOCK_SEQPACKET: return real length if MSG_TRUNC is set */
1353         if (sk->sk_type == SOCK_SEQPACKET && (flags & MSG_TRUNC))
1354                 copied = rlen;
1355
1356         return copied;
1357 }
1358
1359 static inline __poll_t iucv_accept_poll(struct sock *parent)
1360 {
1361         struct iucv_sock *isk, *n;
1362         struct sock *sk;
1363
1364         list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
1365                 sk = (struct sock *) isk;
1366
1367                 if (sk->sk_state == IUCV_CONNECTED)
1368                         return EPOLLIN | EPOLLRDNORM;
1369         }
1370
1371         return 0;
1372 }
1373
1374 static __poll_t iucv_sock_poll(struct file *file, struct socket *sock,
1375                                poll_table *wait)
1376 {
1377         struct sock *sk = sock->sk;
1378         __poll_t mask = 0;
1379
1380         sock_poll_wait(file, sock, wait);
1381
1382         if (sk->sk_state == IUCV_LISTEN)
1383                 return iucv_accept_poll(sk);
1384
1385         if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
1386                 mask |= EPOLLERR |
1387                         (sock_flag(sk, SOCK_SELECT_ERR_QUEUE) ? EPOLLPRI : 0);
1388
1389         if (sk->sk_shutdown & RCV_SHUTDOWN)
1390                 mask |= EPOLLRDHUP;
1391
1392         if (sk->sk_shutdown == SHUTDOWN_MASK)
1393                 mask |= EPOLLHUP;
1394
1395         if (!skb_queue_empty(&sk->sk_receive_queue) ||
1396             (sk->sk_shutdown & RCV_SHUTDOWN))
1397                 mask |= EPOLLIN | EPOLLRDNORM;
1398
1399         if (sk->sk_state == IUCV_CLOSED)
1400                 mask |= EPOLLHUP;
1401
1402         if (sk->sk_state == IUCV_DISCONN)
1403                 mask |= EPOLLIN;
1404
1405         if (sock_writeable(sk) && iucv_below_msglim(sk))
1406                 mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND;
1407         else
1408                 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1409
1410         return mask;
1411 }
1412
1413 static int iucv_sock_shutdown(struct socket *sock, int how)
1414 {
1415         struct sock *sk = sock->sk;
1416         struct iucv_sock *iucv = iucv_sk(sk);
1417         struct iucv_message txmsg;
1418         int err = 0;
1419
1420         how++;
1421
1422         if ((how & ~SHUTDOWN_MASK) || !how)
1423                 return -EINVAL;
1424
1425         lock_sock(sk);
1426         switch (sk->sk_state) {
1427         case IUCV_LISTEN:
1428         case IUCV_DISCONN:
1429         case IUCV_CLOSING:
1430         case IUCV_CLOSED:
1431                 err = -ENOTCONN;
1432                 goto fail;
1433         default:
1434                 break;
1435         }
1436
1437         if ((how == SEND_SHUTDOWN || how == SHUTDOWN_MASK) &&
1438             sk->sk_state == IUCV_CONNECTED) {
1439                 if (iucv->transport == AF_IUCV_TRANS_IUCV) {
1440                         txmsg.class = 0;
1441                         txmsg.tag = 0;
1442                         err = pr_iucv->message_send(iucv->path, &txmsg,
1443                                 IUCV_IPRMDATA, 0, (void *) iprm_shutdown, 8);
1444                         if (err) {
1445                                 switch (err) {
1446                                 case 1:
1447                                         err = -ENOTCONN;
1448                                         break;
1449                                 case 2:
1450                                         err = -ECONNRESET;
1451                                         break;
1452                                 default:
1453                                         err = -ENOTCONN;
1454                                         break;
1455                                 }
1456                         }
1457                 } else
1458                         iucv_send_ctrl(sk, AF_IUCV_FLAG_SHT);
1459         }
1460
1461         sk->sk_shutdown |= how;
1462         if (how == RCV_SHUTDOWN || how == SHUTDOWN_MASK) {
1463                 if ((iucv->transport == AF_IUCV_TRANS_IUCV) &&
1464                     iucv->path) {
1465                         err = pr_iucv->path_quiesce(iucv->path, NULL);
1466                         if (err)
1467                                 err = -ENOTCONN;
1468 /*                      skb_queue_purge(&sk->sk_receive_queue); */
1469                 }
1470                 skb_queue_purge(&sk->sk_receive_queue);
1471         }
1472
1473         /* Wake up anyone sleeping in poll */
1474         sk->sk_state_change(sk);
1475
1476 fail:
1477         release_sock(sk);
1478         return err;
1479 }
1480
1481 static int iucv_sock_release(struct socket *sock)
1482 {
1483         struct sock *sk = sock->sk;
1484         int err = 0;
1485
1486         if (!sk)
1487                 return 0;
1488
1489         iucv_sock_close(sk);
1490
1491         sock_orphan(sk);
1492         iucv_sock_kill(sk);
1493         return err;
1494 }
1495
1496 /* getsockopt and setsockopt */
1497 static int iucv_sock_setsockopt(struct socket *sock, int level, int optname,
1498                                 sockptr_t optval, unsigned int optlen)
1499 {
1500         struct sock *sk = sock->sk;
1501         struct iucv_sock *iucv = iucv_sk(sk);
1502         int val;
1503         int rc;
1504
1505         if (level != SOL_IUCV)
1506                 return -ENOPROTOOPT;
1507
1508         if (optlen < sizeof(int))
1509                 return -EINVAL;
1510
1511         if (copy_from_sockptr(&val, optval, sizeof(int)))
1512                 return -EFAULT;
1513
1514         rc = 0;
1515
1516         lock_sock(sk);
1517         switch (optname) {
1518         case SO_IPRMDATA_MSG:
1519                 if (val)
1520                         iucv->flags |= IUCV_IPRMDATA;
1521                 else
1522                         iucv->flags &= ~IUCV_IPRMDATA;
1523                 break;
1524         case SO_MSGLIMIT:
1525                 switch (sk->sk_state) {
1526                 case IUCV_OPEN:
1527                 case IUCV_BOUND:
1528                         if (val < 1 || val > U16_MAX)
1529                                 rc = -EINVAL;
1530                         else
1531                                 iucv->msglimit = val;
1532                         break;
1533                 default:
1534                         rc = -EINVAL;
1535                         break;
1536                 }
1537                 break;
1538         default:
1539                 rc = -ENOPROTOOPT;
1540                 break;
1541         }
1542         release_sock(sk);
1543
1544         return rc;
1545 }
1546
1547 static int iucv_sock_getsockopt(struct socket *sock, int level, int optname,
1548                                 char __user *optval, int __user *optlen)
1549 {
1550         struct sock *sk = sock->sk;
1551         struct iucv_sock *iucv = iucv_sk(sk);
1552         unsigned int val;
1553         int len;
1554
1555         if (level != SOL_IUCV)
1556                 return -ENOPROTOOPT;
1557
1558         if (get_user(len, optlen))
1559                 return -EFAULT;
1560
1561         if (len < 0)
1562                 return -EINVAL;
1563
1564         len = min_t(unsigned int, len, sizeof(int));
1565
1566         switch (optname) {
1567         case SO_IPRMDATA_MSG:
1568                 val = (iucv->flags & IUCV_IPRMDATA) ? 1 : 0;
1569                 break;
1570         case SO_MSGLIMIT:
1571                 lock_sock(sk);
1572                 val = (iucv->path != NULL) ? iucv->path->msglim /* connected */
1573                                            : iucv->msglimit;    /* default */
1574                 release_sock(sk);
1575                 break;
1576         case SO_MSGSIZE:
1577                 if (sk->sk_state == IUCV_OPEN)
1578                         return -EBADFD;
1579                 val = (iucv->hs_dev) ? iucv->hs_dev->mtu -
1580                                 sizeof(struct af_iucv_trans_hdr) - ETH_HLEN :
1581                                 0x7fffffff;
1582                 break;
1583         default:
1584                 return -ENOPROTOOPT;
1585         }
1586
1587         if (put_user(len, optlen))
1588                 return -EFAULT;
1589         if (copy_to_user(optval, &val, len))
1590                 return -EFAULT;
1591
1592         return 0;
1593 }
1594
1595
1596 /* Callback wrappers - called from iucv base support */
1597 static int iucv_callback_connreq(struct iucv_path *path,
1598                                  u8 ipvmid[8], u8 ipuser[16])
1599 {
1600         unsigned char user_data[16];
1601         unsigned char nuser_data[16];
1602         unsigned char src_name[8];
1603         struct sock *sk, *nsk;
1604         struct iucv_sock *iucv, *niucv;
1605         int err;
1606
1607         memcpy(src_name, ipuser, 8);
1608         EBCASC(src_name, 8);
1609         /* Find out if this path belongs to af_iucv. */
1610         read_lock(&iucv_sk_list.lock);
1611         iucv = NULL;
1612         sk = NULL;
1613         sk_for_each(sk, &iucv_sk_list.head)
1614                 if (sk->sk_state == IUCV_LISTEN &&
1615                     !memcmp(&iucv_sk(sk)->src_name, src_name, 8)) {
1616                         /*
1617                          * Found a listening socket with
1618                          * src_name == ipuser[0-7].
1619                          */
1620                         iucv = iucv_sk(sk);
1621                         break;
1622                 }
1623         read_unlock(&iucv_sk_list.lock);
1624         if (!iucv)
1625                 /* No socket found, not one of our paths. */
1626                 return -EINVAL;
1627
1628         bh_lock_sock(sk);
1629
1630         /* Check if parent socket is listening */
1631         low_nmcpy(user_data, iucv->src_name);
1632         high_nmcpy(user_data, iucv->dst_name);
1633         ASCEBC(user_data, sizeof(user_data));
1634         if (sk->sk_state != IUCV_LISTEN) {
1635                 err = pr_iucv->path_sever(path, user_data);
1636                 iucv_path_free(path);
1637                 goto fail;
1638         }
1639
1640         /* Check for backlog size */
1641         if (sk_acceptq_is_full(sk)) {
1642                 err = pr_iucv->path_sever(path, user_data);
1643                 iucv_path_free(path);
1644                 goto fail;
1645         }
1646
1647         /* Create the new socket */
1648         nsk = iucv_sock_alloc(NULL, sk->sk_protocol, GFP_ATOMIC, 0);
1649         if (!nsk) {
1650                 err = pr_iucv->path_sever(path, user_data);
1651                 iucv_path_free(path);
1652                 goto fail;
1653         }
1654
1655         niucv = iucv_sk(nsk);
1656         iucv_sock_init(nsk, sk);
1657         niucv->transport = AF_IUCV_TRANS_IUCV;
1658         nsk->sk_allocation |= GFP_DMA;
1659
1660         /* Set the new iucv_sock */
1661         memcpy(niucv->dst_name, ipuser + 8, 8);
1662         EBCASC(niucv->dst_name, 8);
1663         memcpy(niucv->dst_user_id, ipvmid, 8);
1664         memcpy(niucv->src_name, iucv->src_name, 8);
1665         memcpy(niucv->src_user_id, iucv->src_user_id, 8);
1666         niucv->path = path;
1667
1668         /* Call iucv_accept */
1669         high_nmcpy(nuser_data, ipuser + 8);
1670         memcpy(nuser_data + 8, niucv->src_name, 8);
1671         ASCEBC(nuser_data + 8, 8);
1672
1673         /* set message limit for path based on msglimit of accepting socket */
1674         niucv->msglimit = iucv->msglimit;
1675         path->msglim = iucv->msglimit;
1676         err = pr_iucv->path_accept(path, &af_iucv_handler, nuser_data, nsk);
1677         if (err) {
1678                 iucv_sever_path(nsk, 1);
1679                 iucv_sock_kill(nsk);
1680                 goto fail;
1681         }
1682
1683         iucv_accept_enqueue(sk, nsk);
1684
1685         /* Wake up accept */
1686         nsk->sk_state = IUCV_CONNECTED;
1687         sk->sk_data_ready(sk);
1688         err = 0;
1689 fail:
1690         bh_unlock_sock(sk);
1691         return 0;
1692 }
1693
1694 static void iucv_callback_connack(struct iucv_path *path, u8 ipuser[16])
1695 {
1696         struct sock *sk = path->private;
1697
1698         sk->sk_state = IUCV_CONNECTED;
1699         sk->sk_state_change(sk);
1700 }
1701
1702 static void iucv_callback_rx(struct iucv_path *path, struct iucv_message *msg)
1703 {
1704         struct sock *sk = path->private;
1705         struct iucv_sock *iucv = iucv_sk(sk);
1706         struct sk_buff *skb;
1707         struct sock_msg_q *save_msg;
1708         int len;
1709
1710         if (sk->sk_shutdown & RCV_SHUTDOWN) {
1711                 pr_iucv->message_reject(path, msg);
1712                 return;
1713         }
1714
1715         spin_lock(&iucv->message_q.lock);
1716
1717         if (!list_empty(&iucv->message_q.list) ||
1718             !skb_queue_empty(&iucv->backlog_skb_q))
1719                 goto save_message;
1720
1721         len = atomic_read(&sk->sk_rmem_alloc);
1722         len += SKB_TRUESIZE(iucv_msg_length(msg));
1723         if (len > sk->sk_rcvbuf)
1724                 goto save_message;
1725
1726         skb = alloc_iucv_recv_skb(iucv_msg_length(msg));
1727         if (!skb)
1728                 goto save_message;
1729
1730         iucv_process_message(sk, skb, path, msg);
1731         goto out_unlock;
1732
1733 save_message:
1734         save_msg = kzalloc(sizeof(struct sock_msg_q), GFP_ATOMIC | GFP_DMA);
1735         if (!save_msg)
1736                 goto out_unlock;
1737         save_msg->path = path;
1738         save_msg->msg = *msg;
1739
1740         list_add_tail(&save_msg->list, &iucv->message_q.list);
1741
1742 out_unlock:
1743         spin_unlock(&iucv->message_q.lock);
1744 }
1745
1746 static void iucv_callback_txdone(struct iucv_path *path,
1747                                  struct iucv_message *msg)
1748 {
1749         struct sock *sk = path->private;
1750         struct sk_buff *this = NULL;
1751         struct sk_buff_head *list = &iucv_sk(sk)->send_skb_q;
1752         struct sk_buff *list_skb;
1753         unsigned long flags;
1754
1755         bh_lock_sock(sk);
1756
1757         spin_lock_irqsave(&list->lock, flags);
1758         skb_queue_walk(list, list_skb) {
1759                 if (msg->tag == IUCV_SKB_CB(list_skb)->tag) {
1760                         this = list_skb;
1761                         break;
1762                 }
1763         }
1764         if (this)
1765                 __skb_unlink(this, list);
1766         spin_unlock_irqrestore(&list->lock, flags);
1767
1768         if (this) {
1769                 kfree_skb(this);
1770                 /* wake up any process waiting for sending */
1771                 iucv_sock_wake_msglim(sk);
1772         }
1773
1774         if (sk->sk_state == IUCV_CLOSING) {
1775                 if (skb_queue_empty(&iucv_sk(sk)->send_skb_q)) {
1776                         sk->sk_state = IUCV_CLOSED;
1777                         sk->sk_state_change(sk);
1778                 }
1779         }
1780         bh_unlock_sock(sk);
1781
1782 }
1783
1784 static void iucv_callback_connrej(struct iucv_path *path, u8 ipuser[16])
1785 {
1786         struct sock *sk = path->private;
1787
1788         if (sk->sk_state == IUCV_CLOSED)
1789                 return;
1790
1791         bh_lock_sock(sk);
1792         iucv_sever_path(sk, 1);
1793         sk->sk_state = IUCV_DISCONN;
1794
1795         sk->sk_state_change(sk);
1796         bh_unlock_sock(sk);
1797 }
1798
1799 /* called if the other communication side shuts down its RECV direction;
1800  * in turn, the callback sets SEND_SHUTDOWN to disable sending of data.
1801  */
1802 static void iucv_callback_shutdown(struct iucv_path *path, u8 ipuser[16])
1803 {
1804         struct sock *sk = path->private;
1805
1806         bh_lock_sock(sk);
1807         if (sk->sk_state != IUCV_CLOSED) {
1808                 sk->sk_shutdown |= SEND_SHUTDOWN;
1809                 sk->sk_state_change(sk);
1810         }
1811         bh_unlock_sock(sk);
1812 }
1813
1814 /***************** HiperSockets transport callbacks ********************/
1815 static void afiucv_swap_src_dest(struct sk_buff *skb)
1816 {
1817         struct af_iucv_trans_hdr *trans_hdr = iucv_trans_hdr(skb);
1818         char tmpID[8];
1819         char tmpName[8];
1820
1821         ASCEBC(trans_hdr->destUserID, sizeof(trans_hdr->destUserID));
1822         ASCEBC(trans_hdr->destAppName, sizeof(trans_hdr->destAppName));
1823         ASCEBC(trans_hdr->srcUserID, sizeof(trans_hdr->srcUserID));
1824         ASCEBC(trans_hdr->srcAppName, sizeof(trans_hdr->srcAppName));
1825         memcpy(tmpID, trans_hdr->srcUserID, 8);
1826         memcpy(tmpName, trans_hdr->srcAppName, 8);
1827         memcpy(trans_hdr->srcUserID, trans_hdr->destUserID, 8);
1828         memcpy(trans_hdr->srcAppName, trans_hdr->destAppName, 8);
1829         memcpy(trans_hdr->destUserID, tmpID, 8);
1830         memcpy(trans_hdr->destAppName, tmpName, 8);
1831         skb_push(skb, ETH_HLEN);
1832         memset(skb->data, 0, ETH_HLEN);
1833 }
1834
1835 /**
1836  * afiucv_hs_callback_syn - react on received SYN
1837  **/
1838 static int afiucv_hs_callback_syn(struct sock *sk, struct sk_buff *skb)
1839 {
1840         struct af_iucv_trans_hdr *trans_hdr = iucv_trans_hdr(skb);
1841         struct sock *nsk;
1842         struct iucv_sock *iucv, *niucv;
1843         int err;
1844
1845         iucv = iucv_sk(sk);
1846         if (!iucv) {
1847                 /* no sock - connection refused */
1848                 afiucv_swap_src_dest(skb);
1849                 trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN;
1850                 err = dev_queue_xmit(skb);
1851                 goto out;
1852         }
1853
1854         nsk = iucv_sock_alloc(NULL, sk->sk_protocol, GFP_ATOMIC, 0);
1855         bh_lock_sock(sk);
1856         if ((sk->sk_state != IUCV_LISTEN) ||
1857             sk_acceptq_is_full(sk) ||
1858             !nsk) {
1859                 /* error on server socket - connection refused */
1860                 afiucv_swap_src_dest(skb);
1861                 trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN;
1862                 err = dev_queue_xmit(skb);
1863                 iucv_sock_kill(nsk);
1864                 bh_unlock_sock(sk);
1865                 goto out;
1866         }
1867
1868         niucv = iucv_sk(nsk);
1869         iucv_sock_init(nsk, sk);
1870         niucv->transport = AF_IUCV_TRANS_HIPER;
1871         niucv->msglimit = iucv->msglimit;
1872         if (!trans_hdr->window)
1873                 niucv->msglimit_peer = IUCV_HIPER_MSGLIM_DEFAULT;
1874         else
1875                 niucv->msglimit_peer = trans_hdr->window;
1876         memcpy(niucv->dst_name, trans_hdr->srcAppName, 8);
1877         memcpy(niucv->dst_user_id, trans_hdr->srcUserID, 8);
1878         memcpy(niucv->src_name, iucv->src_name, 8);
1879         memcpy(niucv->src_user_id, iucv->src_user_id, 8);
1880         nsk->sk_bound_dev_if = sk->sk_bound_dev_if;
1881         niucv->hs_dev = iucv->hs_dev;
1882         dev_hold(niucv->hs_dev);
1883         afiucv_swap_src_dest(skb);
1884         trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_ACK;
1885         trans_hdr->window = niucv->msglimit;
1886         /* if receiver acks the xmit connection is established */
1887         err = dev_queue_xmit(skb);
1888         if (!err) {
1889                 iucv_accept_enqueue(sk, nsk);
1890                 nsk->sk_state = IUCV_CONNECTED;
1891                 sk->sk_data_ready(sk);
1892         } else
1893                 iucv_sock_kill(nsk);
1894         bh_unlock_sock(sk);
1895
1896 out:
1897         return NET_RX_SUCCESS;
1898 }
1899
1900 /**
1901  * afiucv_hs_callback_synack() - react on received SYN-ACK
1902  **/
1903 static int afiucv_hs_callback_synack(struct sock *sk, struct sk_buff *skb)
1904 {
1905         struct iucv_sock *iucv = iucv_sk(sk);
1906
1907         if (!iucv)
1908                 goto out;
1909         if (sk->sk_state != IUCV_BOUND)
1910                 goto out;
1911         bh_lock_sock(sk);
1912         iucv->msglimit_peer = iucv_trans_hdr(skb)->window;
1913         sk->sk_state = IUCV_CONNECTED;
1914         sk->sk_state_change(sk);
1915         bh_unlock_sock(sk);
1916 out:
1917         kfree_skb(skb);
1918         return NET_RX_SUCCESS;
1919 }
1920
1921 /**
1922  * afiucv_hs_callback_synfin() - react on received SYN_FIN
1923  **/
1924 static int afiucv_hs_callback_synfin(struct sock *sk, struct sk_buff *skb)
1925 {
1926         struct iucv_sock *iucv = iucv_sk(sk);
1927
1928         if (!iucv)
1929                 goto out;
1930         if (sk->sk_state != IUCV_BOUND)
1931                 goto out;
1932         bh_lock_sock(sk);
1933         sk->sk_state = IUCV_DISCONN;
1934         sk->sk_state_change(sk);
1935         bh_unlock_sock(sk);
1936 out:
1937         kfree_skb(skb);
1938         return NET_RX_SUCCESS;
1939 }
1940
1941 /**
1942  * afiucv_hs_callback_fin() - react on received FIN
1943  **/
1944 static int afiucv_hs_callback_fin(struct sock *sk, struct sk_buff *skb)
1945 {
1946         struct iucv_sock *iucv = iucv_sk(sk);
1947
1948         /* other end of connection closed */
1949         if (!iucv)
1950                 goto out;
1951         bh_lock_sock(sk);
1952         if (sk->sk_state == IUCV_CONNECTED) {
1953                 sk->sk_state = IUCV_DISCONN;
1954                 sk->sk_state_change(sk);
1955         }
1956         bh_unlock_sock(sk);
1957 out:
1958         kfree_skb(skb);
1959         return NET_RX_SUCCESS;
1960 }
1961
1962 /**
1963  * afiucv_hs_callback_win() - react on received WIN
1964  **/
1965 static int afiucv_hs_callback_win(struct sock *sk, struct sk_buff *skb)
1966 {
1967         struct iucv_sock *iucv = iucv_sk(sk);
1968
1969         if (!iucv)
1970                 return NET_RX_SUCCESS;
1971
1972         if (sk->sk_state != IUCV_CONNECTED)
1973                 return NET_RX_SUCCESS;
1974
1975         atomic_sub(iucv_trans_hdr(skb)->window, &iucv->msg_sent);
1976         iucv_sock_wake_msglim(sk);
1977         return NET_RX_SUCCESS;
1978 }
1979
1980 /**
1981  * afiucv_hs_callback_rx() - react on received data
1982  **/
1983 static int afiucv_hs_callback_rx(struct sock *sk, struct sk_buff *skb)
1984 {
1985         struct iucv_sock *iucv = iucv_sk(sk);
1986
1987         if (!iucv) {
1988                 kfree_skb(skb);
1989                 return NET_RX_SUCCESS;
1990         }
1991
1992         if (sk->sk_state != IUCV_CONNECTED) {
1993                 kfree_skb(skb);
1994                 return NET_RX_SUCCESS;
1995         }
1996
1997         if (sk->sk_shutdown & RCV_SHUTDOWN) {
1998                 kfree_skb(skb);
1999                 return NET_RX_SUCCESS;
2000         }
2001
2002         /* write stuff from iucv_msg to skb cb */
2003         skb_pull(skb, sizeof(struct af_iucv_trans_hdr));
2004         skb_reset_transport_header(skb);
2005         skb_reset_network_header(skb);
2006         IUCV_SKB_CB(skb)->offset = 0;
2007         if (sk_filter(sk, skb)) {
2008                 atomic_inc(&sk->sk_drops);      /* skb rejected by filter */
2009                 kfree_skb(skb);
2010                 return NET_RX_SUCCESS;
2011         }
2012
2013         spin_lock(&iucv->message_q.lock);
2014         if (skb_queue_empty(&iucv->backlog_skb_q)) {
2015                 if (__sock_queue_rcv_skb(sk, skb))
2016                         /* handle rcv queue full */
2017                         skb_queue_tail(&iucv->backlog_skb_q, skb);
2018         } else
2019                 skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, skb);
2020         spin_unlock(&iucv->message_q.lock);
2021         return NET_RX_SUCCESS;
2022 }
2023
2024 /**
2025  * afiucv_hs_rcv() - base function for arriving data through HiperSockets
2026  *                   transport
2027  *                   called from netif RX softirq
2028  **/
2029 static int afiucv_hs_rcv(struct sk_buff *skb, struct net_device *dev,
2030         struct packet_type *pt, struct net_device *orig_dev)
2031 {
2032         struct sock *sk;
2033         struct iucv_sock *iucv;
2034         struct af_iucv_trans_hdr *trans_hdr;
2035         int err = NET_RX_SUCCESS;
2036         char nullstring[8];
2037
2038         if (!pskb_may_pull(skb, sizeof(*trans_hdr))) {
2039                 WARN_ONCE(1, "AF_IUCV failed to receive skb, len=%u", skb->len);
2040                 kfree_skb(skb);
2041                 return NET_RX_SUCCESS;
2042         }
2043
2044         trans_hdr = iucv_trans_hdr(skb);
2045         EBCASC(trans_hdr->destAppName, sizeof(trans_hdr->destAppName));
2046         EBCASC(trans_hdr->destUserID, sizeof(trans_hdr->destUserID));
2047         EBCASC(trans_hdr->srcAppName, sizeof(trans_hdr->srcAppName));
2048         EBCASC(trans_hdr->srcUserID, sizeof(trans_hdr->srcUserID));
2049         memset(nullstring, 0, sizeof(nullstring));
2050         iucv = NULL;
2051         sk = NULL;
2052         read_lock(&iucv_sk_list.lock);
2053         sk_for_each(sk, &iucv_sk_list.head) {
2054                 if (trans_hdr->flags == AF_IUCV_FLAG_SYN) {
2055                         if ((!memcmp(&iucv_sk(sk)->src_name,
2056                                      trans_hdr->destAppName, 8)) &&
2057                             (!memcmp(&iucv_sk(sk)->src_user_id,
2058                                      trans_hdr->destUserID, 8)) &&
2059                             (!memcmp(&iucv_sk(sk)->dst_name, nullstring, 8)) &&
2060                             (!memcmp(&iucv_sk(sk)->dst_user_id,
2061                                      nullstring, 8))) {
2062                                 iucv = iucv_sk(sk);
2063                                 break;
2064                         }
2065                 } else {
2066                         if ((!memcmp(&iucv_sk(sk)->src_name,
2067                                      trans_hdr->destAppName, 8)) &&
2068                             (!memcmp(&iucv_sk(sk)->src_user_id,
2069                                      trans_hdr->destUserID, 8)) &&
2070                             (!memcmp(&iucv_sk(sk)->dst_name,
2071                                      trans_hdr->srcAppName, 8)) &&
2072                             (!memcmp(&iucv_sk(sk)->dst_user_id,
2073                                      trans_hdr->srcUserID, 8))) {
2074                                 iucv = iucv_sk(sk);
2075                                 break;
2076                         }
2077                 }
2078         }
2079         read_unlock(&iucv_sk_list.lock);
2080         if (!iucv)
2081                 sk = NULL;
2082
2083         /* no sock
2084         how should we send with no sock
2085         1) send without sock no send rc checking?
2086         2) introduce default sock to handle this cases
2087
2088          SYN -> send SYN|ACK in good case, send SYN|FIN in bad case
2089          data -> send FIN
2090          SYN|ACK, SYN|FIN, FIN -> no action? */
2091
2092         switch (trans_hdr->flags) {
2093         case AF_IUCV_FLAG_SYN:
2094                 /* connect request */
2095                 err = afiucv_hs_callback_syn(sk, skb);
2096                 break;
2097         case (AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_ACK):
2098                 /* connect request confirmed */
2099                 err = afiucv_hs_callback_synack(sk, skb);
2100                 break;
2101         case (AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN):
2102                 /* connect request refused */
2103                 err = afiucv_hs_callback_synfin(sk, skb);
2104                 break;
2105         case (AF_IUCV_FLAG_FIN):
2106                 /* close request */
2107                 err = afiucv_hs_callback_fin(sk, skb);
2108                 break;
2109         case (AF_IUCV_FLAG_WIN):
2110                 err = afiucv_hs_callback_win(sk, skb);
2111                 if (skb->len == sizeof(struct af_iucv_trans_hdr)) {
2112                         kfree_skb(skb);
2113                         break;
2114                 }
2115                 fallthrough;    /* and receive non-zero length data */
2116         case (AF_IUCV_FLAG_SHT):
2117                 /* shutdown request */
2118                 fallthrough;    /* and receive zero length data */
2119         case 0:
2120                 /* plain data frame */
2121                 IUCV_SKB_CB(skb)->class = trans_hdr->iucv_hdr.class;
2122                 err = afiucv_hs_callback_rx(sk, skb);
2123                 break;
2124         default:
2125                 kfree_skb(skb);
2126         }
2127
2128         return err;
2129 }
2130
2131 /**
2132  * afiucv_hs_callback_txnotify() - handle send notifcations from HiperSockets
2133  *                                 transport
2134  **/
2135 static void afiucv_hs_callback_txnotify(struct sk_buff *skb,
2136                                         enum iucv_tx_notify n)
2137 {
2138         struct sock *isk = skb->sk;
2139         struct sock *sk = NULL;
2140         struct iucv_sock *iucv = NULL;
2141         struct sk_buff_head *list;
2142         struct sk_buff *list_skb;
2143         struct sk_buff *nskb;
2144         unsigned long flags;
2145
2146         read_lock_irqsave(&iucv_sk_list.lock, flags);
2147         sk_for_each(sk, &iucv_sk_list.head)
2148                 if (sk == isk) {
2149                         iucv = iucv_sk(sk);
2150                         break;
2151                 }
2152         read_unlock_irqrestore(&iucv_sk_list.lock, flags);
2153
2154         if (!iucv || sock_flag(sk, SOCK_ZAPPED))
2155                 return;
2156
2157         list = &iucv->send_skb_q;
2158         spin_lock_irqsave(&list->lock, flags);
2159         skb_queue_walk_safe(list, list_skb, nskb) {
2160                 if (skb_shinfo(list_skb) == skb_shinfo(skb)) {
2161                         switch (n) {
2162                         case TX_NOTIFY_OK:
2163                                 __skb_unlink(list_skb, list);
2164                                 kfree_skb(list_skb);
2165                                 iucv_sock_wake_msglim(sk);
2166                                 break;
2167                         case TX_NOTIFY_PENDING:
2168                                 atomic_inc(&iucv->pendings);
2169                                 break;
2170                         case TX_NOTIFY_DELAYED_OK:
2171                                 __skb_unlink(list_skb, list);
2172                                 atomic_dec(&iucv->pendings);
2173                                 if (atomic_read(&iucv->pendings) <= 0)
2174                                         iucv_sock_wake_msglim(sk);
2175                                 kfree_skb(list_skb);
2176                                 break;
2177                         case TX_NOTIFY_UNREACHABLE:
2178                         case TX_NOTIFY_DELAYED_UNREACHABLE:
2179                         case TX_NOTIFY_TPQFULL: /* not yet used */
2180                         case TX_NOTIFY_GENERALERROR:
2181                         case TX_NOTIFY_DELAYED_GENERALERROR:
2182                                 __skb_unlink(list_skb, list);
2183                                 kfree_skb(list_skb);
2184                                 if (sk->sk_state == IUCV_CONNECTED) {
2185                                         sk->sk_state = IUCV_DISCONN;
2186                                         sk->sk_state_change(sk);
2187                                 }
2188                                 break;
2189                         }
2190                         break;
2191                 }
2192         }
2193         spin_unlock_irqrestore(&list->lock, flags);
2194
2195         if (sk->sk_state == IUCV_CLOSING) {
2196                 if (skb_queue_empty(&iucv_sk(sk)->send_skb_q)) {
2197                         sk->sk_state = IUCV_CLOSED;
2198                         sk->sk_state_change(sk);
2199                 }
2200         }
2201
2202 }
2203
2204 /*
2205  * afiucv_netdev_event: handle netdev notifier chain events
2206  */
2207 static int afiucv_netdev_event(struct notifier_block *this,
2208                                unsigned long event, void *ptr)
2209 {
2210         struct net_device *event_dev = netdev_notifier_info_to_dev(ptr);
2211         struct sock *sk;
2212         struct iucv_sock *iucv;
2213
2214         switch (event) {
2215         case NETDEV_REBOOT:
2216         case NETDEV_GOING_DOWN:
2217                 sk_for_each(sk, &iucv_sk_list.head) {
2218                         iucv = iucv_sk(sk);
2219                         if ((iucv->hs_dev == event_dev) &&
2220                             (sk->sk_state == IUCV_CONNECTED)) {
2221                                 if (event == NETDEV_GOING_DOWN)
2222                                         iucv_send_ctrl(sk, AF_IUCV_FLAG_FIN);
2223                                 sk->sk_state = IUCV_DISCONN;
2224                                 sk->sk_state_change(sk);
2225                         }
2226                 }
2227                 break;
2228         case NETDEV_DOWN:
2229         case NETDEV_UNREGISTER:
2230         default:
2231                 break;
2232         }
2233         return NOTIFY_DONE;
2234 }
2235
2236 static struct notifier_block afiucv_netdev_notifier = {
2237         .notifier_call = afiucv_netdev_event,
2238 };
2239
2240 static const struct proto_ops iucv_sock_ops = {
2241         .family         = PF_IUCV,
2242         .owner          = THIS_MODULE,
2243         .release        = iucv_sock_release,
2244         .bind           = iucv_sock_bind,
2245         .connect        = iucv_sock_connect,
2246         .listen         = iucv_sock_listen,
2247         .accept         = iucv_sock_accept,
2248         .getname        = iucv_sock_getname,
2249         .sendmsg        = iucv_sock_sendmsg,
2250         .recvmsg        = iucv_sock_recvmsg,
2251         .poll           = iucv_sock_poll,
2252         .ioctl          = sock_no_ioctl,
2253         .mmap           = sock_no_mmap,
2254         .socketpair     = sock_no_socketpair,
2255         .shutdown       = iucv_sock_shutdown,
2256         .setsockopt     = iucv_sock_setsockopt,
2257         .getsockopt     = iucv_sock_getsockopt,
2258 };
2259
2260 static int iucv_sock_create(struct net *net, struct socket *sock, int protocol,
2261                             int kern)
2262 {
2263         struct sock *sk;
2264
2265         if (protocol && protocol != PF_IUCV)
2266                 return -EPROTONOSUPPORT;
2267
2268         sock->state = SS_UNCONNECTED;
2269
2270         switch (sock->type) {
2271         case SOCK_STREAM:
2272         case SOCK_SEQPACKET:
2273                 /* currently, proto ops can handle both sk types */
2274                 sock->ops = &iucv_sock_ops;
2275                 break;
2276         default:
2277                 return -ESOCKTNOSUPPORT;
2278         }
2279
2280         sk = iucv_sock_alloc(sock, protocol, GFP_KERNEL, kern);
2281         if (!sk)
2282                 return -ENOMEM;
2283
2284         iucv_sock_init(sk, NULL);
2285
2286         return 0;
2287 }
2288
2289 static const struct net_proto_family iucv_sock_family_ops = {
2290         .family = AF_IUCV,
2291         .owner  = THIS_MODULE,
2292         .create = iucv_sock_create,
2293 };
2294
2295 static struct packet_type iucv_packet_type = {
2296         .type = cpu_to_be16(ETH_P_AF_IUCV),
2297         .func = afiucv_hs_rcv,
2298 };
2299
2300 static int afiucv_iucv_init(void)
2301 {
2302         return pr_iucv->iucv_register(&af_iucv_handler, 0);
2303 }
2304
2305 static void afiucv_iucv_exit(void)
2306 {
2307         pr_iucv->iucv_unregister(&af_iucv_handler, 0);
2308 }
2309
2310 static int __init afiucv_init(void)
2311 {
2312         int err;
2313
2314         if (MACHINE_IS_VM) {
2315                 cpcmd("QUERY USERID", iucv_userid, sizeof(iucv_userid), &err);
2316                 if (unlikely(err)) {
2317                         WARN_ON(err);
2318                         err = -EPROTONOSUPPORT;
2319                         goto out;
2320                 }
2321
2322                 pr_iucv = try_then_request_module(symbol_get(iucv_if), "iucv");
2323                 if (!pr_iucv) {
2324                         printk(KERN_WARNING "iucv_if lookup failed\n");
2325                         memset(&iucv_userid, 0, sizeof(iucv_userid));
2326                 }
2327         } else {
2328                 memset(&iucv_userid, 0, sizeof(iucv_userid));
2329                 pr_iucv = NULL;
2330         }
2331
2332         err = proto_register(&iucv_proto, 0);
2333         if (err)
2334                 goto out;
2335         err = sock_register(&iucv_sock_family_ops);
2336         if (err)
2337                 goto out_proto;
2338
2339         if (pr_iucv) {
2340                 err = afiucv_iucv_init();
2341                 if (err)
2342                         goto out_sock;
2343         }
2344
2345         err = register_netdevice_notifier(&afiucv_netdev_notifier);
2346         if (err)
2347                 goto out_notifier;
2348
2349         dev_add_pack(&iucv_packet_type);
2350         return 0;
2351
2352 out_notifier:
2353         if (pr_iucv)
2354                 afiucv_iucv_exit();
2355 out_sock:
2356         sock_unregister(PF_IUCV);
2357 out_proto:
2358         proto_unregister(&iucv_proto);
2359 out:
2360         if (pr_iucv)
2361                 symbol_put(iucv_if);
2362         return err;
2363 }
2364
2365 static void __exit afiucv_exit(void)
2366 {
2367         if (pr_iucv) {
2368                 afiucv_iucv_exit();
2369                 symbol_put(iucv_if);
2370         }
2371
2372         unregister_netdevice_notifier(&afiucv_netdev_notifier);
2373         dev_remove_pack(&iucv_packet_type);
2374         sock_unregister(PF_IUCV);
2375         proto_unregister(&iucv_proto);
2376 }
2377
2378 module_init(afiucv_init);
2379 module_exit(afiucv_exit);
2380
2381 MODULE_AUTHOR("Jennifer Hunt <jenhunt@us.ibm.com>");
2382 MODULE_DESCRIPTION("IUCV Sockets ver " VERSION);
2383 MODULE_VERSION(VERSION);
2384 MODULE_LICENSE("GPL");
2385 MODULE_ALIAS_NETPROTO(PF_IUCV);