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 <[email protected]>
   8  *              Hendrik Brueckner <[email protected]>
   9  *  PM functions:
  10  *              Ursula Braun <[email protected]>
  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/types.h>
  18 #include <linux/list.h>
  19 #include <linux/errno.h>
  20 #include <linux/kernel.h>
  21 #include <linux/sched/signal.h>
  22 #include <linux/slab.h>
  23 #include <linux/skbuff.h>
  24 #include <linux/init.h>
  25 #include <linux/poll.h>
  26 #include <linux/security.h>
  27 #include <net/sock.h>
  28 #include <asm/ebcdic.h>
  29 #include <asm/cpcmd.h>
  30 #include <linux/kmod.h>
  31
  32 #include <net/iucv/af_iucv.h>
  33
  34 #define VERSION "1.2"
  35
  36 static char iucv_userid[80];
  37
  38 static const struct proto_ops iucv_sock_ops;
  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     FIELD_SIZEOF(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 void iucv_sock_kill(struct sock *sk);
  88 static void iucv_sock_close(struct sock *sk);
  89 static void iucv_sever_path(struct sock *, int);
  90
  91 static int afiucv_hs_rcv(struct sk_buff *skb, struct net_device *dev,
  92         struct packet_type *pt, struct net_device *orig_dev);
  93 static int afiucv_hs_send(struct iucv_message *imsg, struct sock *sock,
  94                    struct sk_buff *skb, u8 flags);
  95 static void afiucv_hs_callback_txnotify(struct sk_buff *, enum iucv_tx_notify);
  96
  97 /* Call Back functions */
  98 static void iucv_callback_rx(struct iucv_path *, struct iucv_message *);
  99 static void iucv_callback_txdone(struct iucv_path *, struct iucv_message *);
 100 static void iucv_callback_connack(struct iucv_path *, u8 *);
 101 static int iucv_callback_connreq(struct iucv_path *, u8 *, u8 *);
 102 static void iucv_callback_connrej(struct iucv_path *, u8 *);
 103 static void iucv_callback_shutdown(struct iucv_path *, u8 *);
 104
 105 static struct iucv_sock_list iucv_sk_list = {
 106         .lock = __RW_LOCK_UNLOCKED(iucv_sk_list.lock),
 107         .autobind_name = ATOMIC_INIT(0)
 108 };
 109
 110 static struct iucv_handler af_iucv_handler = {
 111         .path_pending     = iucv_callback_connreq,
 112         .path_complete    = iucv_callback_connack,
 113         .path_severed     = iucv_callback_connrej,
 114         .message_pending  = iucv_callback_rx,
 115         .message_complete = iucv_callback_txdone,
 116         .path_quiesced    = iucv_callback_shutdown,
 117 };
 118
 119 static inline void high_nmcpy(unsigned char *dst, char *src)
 120 {
 121        memcpy(dst, src, 8);
 122 }
 123
 124 static inline void low_nmcpy(unsigned char *dst, char *src)
 125 {
 126        memcpy(&dst[8], src, 8);
 127 }
 128
 129 static int afiucv_pm_prepare(struct device *dev)
 130 {
 131 #ifdef CONFIG_PM_DEBUG
 132         printk(KERN_WARNING "afiucv_pm_prepare\n");
 133 #endif
 134         return 0;
 135 }
 136
 137 static void afiucv_pm_complete(struct device *dev)
 138 {
 139 #ifdef CONFIG_PM_DEBUG
 140         printk(KERN_WARNING "afiucv_pm_complete\n");
 141 #endif
 142 }
 143
 144 /**
 145  * afiucv_pm_freeze() - Freeze PM callback
 146  * @dev:        AFIUCV dummy device
 147  *
 148  * Sever all established IUCV communication pathes
 149  */
 150 static int afiucv_pm_freeze(struct device *dev)
 151 {
 152         struct iucv_sock *iucv;
 153         struct sock *sk;
 154
 155 #ifdef CONFIG_PM_DEBUG
 156         printk(KERN_WARNING "afiucv_pm_freeze\n");
 157 #endif
 158         read_lock(&iucv_sk_list.lock);
 159         sk_for_each(sk, &iucv_sk_list.head) {
 160                 iucv = iucv_sk(sk);
 161                 switch (sk->sk_state) {
 162                 case IUCV_DISCONN:
 163                 case IUCV_CLOSING:
 164                 case IUCV_CONNECTED:
 165                         iucv_sever_path(sk, 0);
 166                         break;
 167                 case IUCV_OPEN:
 168                 case IUCV_BOUND:
 169                 case IUCV_LISTEN:
 170                 case IUCV_CLOSED:
 171                 default:
 172                         break;
 173                 }
 174                 skb_queue_purge(&iucv->send_skb_q);
 175                 skb_queue_purge(&iucv->backlog_skb_q);
 176         }
 177         read_unlock(&iucv_sk_list.lock);
 178         return 0;
 179 }
 180
 181 /**
 182  * afiucv_pm_restore_thaw() - Thaw and restore PM callback
 183  * @dev:        AFIUCV dummy device
 184  *
 185  * socket clean up after freeze
 186  */
 187 static int afiucv_pm_restore_thaw(struct device *dev)
 188 {
 189         struct sock *sk;
 190
 191 #ifdef CONFIG_PM_DEBUG
 192         printk(KERN_WARNING "afiucv_pm_restore_thaw\n");
 193 #endif
 194         read_lock(&iucv_sk_list.lock);
 195         sk_for_each(sk, &iucv_sk_list.head) {
 196                 switch (sk->sk_state) {
 197                 case IUCV_CONNECTED:
 198                         sk->sk_err = EPIPE;
 199                         sk->sk_state = IUCV_DISCONN;
 200                         sk->sk_state_change(sk);
 201                         break;
 202                 case IUCV_DISCONN:
 203                 case IUCV_CLOSING:
 204                 case IUCV_LISTEN:
 205                 case IUCV_BOUND:
 206                 case IUCV_OPEN:
 207                 default:
 208                         break;
 209                 }
 210         }
 211         read_unlock(&iucv_sk_list.lock);
 212         return 0;
 213 }
 214
 215 static const struct dev_pm_ops afiucv_pm_ops = {
 216         .prepare = afiucv_pm_prepare,
 217         .complete = afiucv_pm_complete,
 218         .freeze = afiucv_pm_freeze,
 219         .thaw = afiucv_pm_restore_thaw,
 220         .restore = afiucv_pm_restore_thaw,
 221 };
 222
 223 static struct device_driver af_iucv_driver = {
 224         .owner = THIS_MODULE,
 225         .name = "afiucv",
 226         .bus  = NULL,
 227         .pm   = &afiucv_pm_ops,
 228 };
 229
 230 /* dummy device used as trigger for PM functions */
 231 static struct device *af_iucv_dev;
 232
 233 /**
 234  * iucv_msg_length() - Returns the length of an iucv message.
 235  * @msg:        Pointer to struct iucv_message, MUST NOT be NULL
 236  *
 237  * The function returns the length of the specified iucv message @msg of data
 238  * stored in a buffer and of data stored in the parameter list (PRMDATA).
 239  *
 240  * For IUCV_IPRMDATA, AF_IUCV uses the following convention to transport socket
 241  * data:
 242  *      PRMDATA[0..6]   socket data (max 7 bytes);
 243  *      PRMDATA[7]      socket data length value (len is 0xff - PRMDATA[7])
 244  *
 245  * The socket data length is computed by subtracting the socket data length
 246  * value from 0xFF.
 247  * If the socket data len is greater 7, then PRMDATA can be used for special
 248  * notifications (see iucv_sock_shutdown); and further,
 249  * if the socket data len is > 7, the function returns 8.
 250  *
 251  * Use this function to allocate socket buffers to store iucv message data.
 252  */
 253 static inline size_t iucv_msg_length(struct iucv_message *msg)
 254 {
 255         size_t datalen;
 256
 257         if (msg->flags & IUCV_IPRMDATA) {
 258                 datalen = 0xff - msg->rmmsg[7];
 259                 return (datalen < 8) ? datalen : 8;
 260         }
 261         return msg->length;
 262 }
 263
 264 /**
 265  * iucv_sock_in_state() - check for specific states
 266  * @sk:         sock structure
 267  * @state:      first iucv sk state
 268  * @state:      second iucv sk state
 269  *
 270  * Returns true if the socket in either in the first or second state.
 271  */
 272 static int iucv_sock_in_state(struct sock *sk, int state, int state2)
 273 {
 274         return (sk->sk_state == state || sk->sk_state == state2);
 275 }
 276
 277 /**
 278  * iucv_below_msglim() - function to check if messages can be sent
 279  * @sk:         sock structure
 280  *
 281  * Returns true if the send queue length is lower than the message limit.
 282  * Always returns true if the socket is not connected (no iucv path for
 283  * checking the message limit).
 284  */
 285 static inline int iucv_below_msglim(struct sock *sk)
 286 {
 287         struct iucv_sock *iucv = iucv_sk(sk);
 288
 289         if (sk->sk_state != IUCV_CONNECTED)
 290                 return 1;
 291         if (iucv->transport == AF_IUCV_TRANS_IUCV)
 292                 return (skb_queue_len(&iucv->send_skb_q) < iucv->path->msglim);
 293         else
 294                 return ((atomic_read(&iucv->msg_sent) < iucv->msglimit_peer) &&
 295                         (atomic_read(&iucv->pendings) <= 0));
 296 }
 297
 298 /**
 299  * iucv_sock_wake_msglim() - Wake up thread waiting on msg limit
 300  */
 301 static void iucv_sock_wake_msglim(struct sock *sk)
 302 {
 303         struct socket_wq *wq;
 304
 305         rcu_read_lock();
 306         wq = rcu_dereference(sk->sk_wq);
 307         if (skwq_has_sleeper(wq))
 308                 wake_up_interruptible_all(&wq->wait);
 309         sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
 310         rcu_read_unlock();
 311 }
 312
 313 /**
 314  * afiucv_hs_send() - send a message through HiperSockets transport
 315  */
 316 static int afiucv_hs_send(struct iucv_message *imsg, struct sock *sock,
 317                    struct sk_buff *skb, u8 flags)
 318 {
 319         struct iucv_sock *iucv = iucv_sk(sock);
 320         struct af_iucv_trans_hdr *phs_hdr;
 321         struct sk_buff *nskb;
 322         int err, confirm_recv = 0;
 323
 324         phs_hdr = skb_push(skb, sizeof(*phs_hdr));
 325         memset(phs_hdr, 0, sizeof(*phs_hdr));
 326         skb_reset_network_header(skb);
 327
 328         phs_hdr->magic = ETH_P_AF_IUCV;
 329         phs_hdr->version = 1;
 330         phs_hdr->flags = flags;
 331         if (flags == AF_IUCV_FLAG_SYN)
 332                 phs_hdr->window = iucv->msglimit;
 333         else if ((flags == AF_IUCV_FLAG_WIN) || !flags) {
 334                 confirm_recv = atomic_read(&iucv->msg_recv);
 335                 phs_hdr->window = confirm_recv;
 336                 if (confirm_recv)
 337                         phs_hdr->flags = phs_hdr->flags | AF_IUCV_FLAG_WIN;
 338         }
 339         memcpy(phs_hdr->destUserID, iucv->dst_user_id, 8);
 340         memcpy(phs_hdr->destAppName, iucv->dst_name, 8);
 341         memcpy(phs_hdr->srcUserID, iucv->src_user_id, 8);
 342         memcpy(phs_hdr->srcAppName, iucv->src_name, 8);
 343         ASCEBC(phs_hdr->destUserID, sizeof(phs_hdr->destUserID));
 344         ASCEBC(phs_hdr->destAppName, sizeof(phs_hdr->destAppName));
 345         ASCEBC(phs_hdr->srcUserID, sizeof(phs_hdr->srcUserID));
 346         ASCEBC(phs_hdr->srcAppName, sizeof(phs_hdr->srcAppName));
 347         if (imsg)
 348                 memcpy(&phs_hdr->iucv_hdr, imsg, sizeof(struct iucv_message));
 349
 350         skb_push(skb, ETH_HLEN);
 351         memset(skb->data, 0, ETH_HLEN);
 352
 353         skb->dev = iucv->hs_dev;
 354         if (!skb->dev) {
 355                 err = -ENODEV;
 356                 goto err_free;
 357         }
 358         if (!(skb->dev->flags & IFF_UP) || !netif_carrier_ok(skb->dev)) {
 359                 err = -ENETDOWN;
 360                 goto err_free;
 361         }
 362         if (skb->len > skb->dev->mtu) {
 363                 if (sock->sk_type == SOCK_SEQPACKET) {
 364                         err = -EMSGSIZE;
 365                         goto err_free;
 366                 }
 367                 skb_trim(skb, skb->dev->mtu);
 368         }
 369         skb->protocol = cpu_to_be16(ETH_P_AF_IUCV);
 370         nskb = skb_clone(skb, GFP_ATOMIC);
 371         if (!nskb) {
 372                 err = -ENOMEM;
 373                 goto err_free;
 374         }
 375
 376         skb_queue_tail(&iucv->send_skb_q, nskb);
 377         err = dev_queue_xmit(skb);
 378         if (net_xmit_eval(err)) {
 379                 skb_unlink(nskb, &iucv->send_skb_q);
 380                 kfree_skb(nskb);
 381         } else {
 382                 atomic_sub(confirm_recv, &iucv->msg_recv);
 383                 WARN_ON(atomic_read(&iucv->msg_recv) < 0);
 384         }
 385         return net_xmit_eval(err);
 386
 387 err_free:
 388         kfree_skb(skb);
 389         return err;
 390 }
 391
 392 static struct sock *__iucv_get_sock_by_name(char *nm)
 393 {
 394         struct sock *sk;
 395
 396         sk_for_each(sk, &iucv_sk_list.head)
 397                 if (!memcmp(&iucv_sk(sk)->src_name, nm, 8))
 398                         return sk;
 399
 400         return NULL;
 401 }
 402
 403 static void iucv_sock_destruct(struct sock *sk)
 404 {
 405         skb_queue_purge(&sk->sk_receive_queue);
 406         skb_queue_purge(&sk->sk_error_queue);
 407
 408         sk_mem_reclaim(sk);
 409
 410         if (!sock_flag(sk, SOCK_DEAD)) {
 411                 pr_err("Attempt to release alive iucv socket %p\n", sk);
 412                 return;
 413         }
 414
 415         WARN_ON(atomic_read(&sk->sk_rmem_alloc));
 416         WARN_ON(refcount_read(&sk->sk_wmem_alloc));
 417         WARN_ON(sk->sk_wmem_queued);
 418         WARN_ON(sk->sk_forward_alloc);
 419 }
 420
 421 /* Cleanup Listen */
 422 static void iucv_sock_cleanup_listen(struct sock *parent)
 423 {
 424         struct sock *sk;
 425
 426         /* Close non-accepted connections */
 427         while ((sk = iucv_accept_dequeue(parent, NULL))) {
 428                 iucv_sock_close(sk);
 429                 iucv_sock_kill(sk);
 430         }
 431
 432         parent->sk_state = IUCV_CLOSED;
 433 }
 434
 435 /* Kill socket (only if zapped and orphaned) */
 436 static void iucv_sock_kill(struct sock *sk)
 437 {
 438         if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket)
 439                 return;
 440
 441         iucv_sock_unlink(&iucv_sk_list, sk);
 442         sock_set_flag(sk, SOCK_DEAD);
 443         sock_put(sk);
 444 }
 445
 446 /* Terminate an IUCV path */
 447 static void iucv_sever_path(struct sock *sk, int with_user_data)
 448 {
 449         unsigned char user_data[16];
 450         struct iucv_sock *iucv = iucv_sk(sk);
 451         struct iucv_path *path = iucv->path;
 452
 453         if (iucv->path) {
 454                 iucv->path = NULL;
 455                 if (with_user_data) {
 456                         low_nmcpy(user_data, iucv->src_name);
 457                         high_nmcpy(user_data, iucv->dst_name);
 458                         ASCEBC(user_data, sizeof(user_data));
 459                         pr_iucv->path_sever(path, user_data);
 460                 } else
 461                         pr_iucv->path_sever(path, NULL);
 462                 iucv_path_free(path);
 463         }
 464 }
 465
 466 /* Send controlling flags through an IUCV socket for HIPER transport */
 467 static int iucv_send_ctrl(struct sock *sk, u8 flags)
 468 {
 469         int err = 0;
 470         int blen;
 471         struct sk_buff *skb;
 472         u8 shutdown = 0;
 473
 474         blen = sizeof(struct af_iucv_trans_hdr) + ETH_HLEN;
 475         if (sk->sk_shutdown & SEND_SHUTDOWN) {
 476                 /* controlling flags should be sent anyway */
 477                 shutdown = sk->sk_shutdown;
 478                 sk->sk_shutdown &= RCV_SHUTDOWN;
 479         }
 480         skb = sock_alloc_send_skb(sk, blen, 1, &err);
 481         if (skb) {
 482                 skb_reserve(skb, blen);
 483                 err = afiucv_hs_send(NULL, sk, skb, flags);
 484         }
 485         if (shutdown)
 486                 sk->sk_shutdown = shutdown;
 487         return err;
 488 }
 489
 490 /* Close an IUCV socket */
 491 static void iucv_sock_close(struct sock *sk)
 492 {
 493         struct iucv_sock *iucv = iucv_sk(sk);
 494         unsigned long timeo;
 495         int err = 0;
 496
 497         lock_sock(sk);
 498
 499         switch (sk->sk_state) {
 500         case IUCV_LISTEN:
 501                 iucv_sock_cleanup_listen(sk);
 502                 break;
 503
 504         case IUCV_CONNECTED:
 505                 if (iucv->transport == AF_IUCV_TRANS_HIPER) {
 506                         err = iucv_send_ctrl(sk, AF_IUCV_FLAG_FIN);
 507                         sk->sk_state = IUCV_DISCONN;
 508                         sk->sk_state_change(sk);
 509                 }
 510         case IUCV_DISCONN:   /* fall through */
 511                 sk->sk_state = IUCV_CLOSING;
 512                 sk->sk_state_change(sk);
 513
 514                 if (!err && !skb_queue_empty(&iucv->send_skb_q)) {
 515                         if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime)
 516                                 timeo = sk->sk_lingertime;
 517                         else
 518                                 timeo = IUCV_DISCONN_TIMEOUT;
 519                         iucv_sock_wait(sk,
 520                                         iucv_sock_in_state(sk, IUCV_CLOSED, 0),
 521                                         timeo);
 522                 }
 523
 524         case IUCV_CLOSING:   /* fall through */
 525                 sk->sk_state = IUCV_CLOSED;
 526                 sk->sk_state_change(sk);
 527
 528                 sk->sk_err = ECONNRESET;
 529                 sk->sk_state_change(sk);
 530
 531                 skb_queue_purge(&iucv->send_skb_q);
 532                 skb_queue_purge(&iucv->backlog_skb_q);
 533
 534         default:   /* fall through */
 535                 iucv_sever_path(sk, 1);
 536         }
 537
 538         if (iucv->hs_dev) {
 539                 dev_put(iucv->hs_dev);
 540                 iucv->hs_dev = NULL;
 541                 sk->sk_bound_dev_if = 0;
 542         }
 543
 544         /* mark socket for deletion by iucv_sock_kill() */
 545         sock_set_flag(sk, SOCK_ZAPPED);
 546
 547         release_sock(sk);
 548 }
 549
 550 static void iucv_sock_init(struct sock *sk, struct sock *parent)
 551 {
 552         if (parent) {
 553                 sk->sk_type = parent->sk_type;
 554                 security_sk_clone(parent, sk);
 555         }
 556 }
 557
 558 static struct sock *iucv_sock_alloc(struct socket *sock, int proto, gfp_t prio, int kern)
 559 {
 560         struct sock *sk;
 561         struct iucv_sock *iucv;
 562
 563         sk = sk_alloc(&init_net, PF_IUCV, prio, &iucv_proto, kern);
 564         if (!sk)
 565                 return NULL;
 566         iucv = iucv_sk(sk);
 567
 568         sock_init_data(sock, sk);
 569         INIT_LIST_HEAD(&iucv->accept_q);
 570         spin_lock_init(&iucv->accept_q_lock);
 571         skb_queue_head_init(&iucv->send_skb_q);
 572         INIT_LIST_HEAD(&iucv->message_q.list);
 573         spin_lock_init(&iucv->message_q.lock);
 574         skb_queue_head_init(&iucv->backlog_skb_q);
 575         iucv->send_tag = 0;
 576         atomic_set(&iucv->pendings, 0);
 577         iucv->flags = 0;
 578         iucv->msglimit = 0;
 579         atomic_set(&iucv->msg_sent, 0);
 580         atomic_set(&iucv->msg_recv, 0);
 581         iucv->path = NULL;
 582         iucv->sk_txnotify = afiucv_hs_callback_txnotify;
 583         memset(&iucv->src_user_id , 0, 32);
 584         if (pr_iucv)
 585                 iucv->transport = AF_IUCV_TRANS_IUCV;
 586         else
 587                 iucv->transport = AF_IUCV_TRANS_HIPER;
 588
 589         sk->sk_destruct = iucv_sock_destruct;
 590         sk->sk_sndtimeo = IUCV_CONN_TIMEOUT;
 591         sk->sk_allocation = GFP_DMA;
 592
 593         sock_reset_flag(sk, SOCK_ZAPPED);
 594
 595         sk->sk_protocol = proto;
 596         sk->sk_state    = IUCV_OPEN;
 597
 598         iucv_sock_link(&iucv_sk_list, sk);
 599         return sk;
 600 }
 601
 602 /* Create an IUCV socket */
 603 static int iucv_sock_create(struct net *net, struct socket *sock, int protocol,
 604                             int kern)
 605 {
 606         struct sock *sk;
 607
 608         if (protocol && protocol != PF_IUCV)
 609                 return -EPROTONOSUPPORT;
 610
 611         sock->state = SS_UNCONNECTED;
 612
 613         switch (sock->type) {
 614         case SOCK_STREAM:
 615                 sock->ops = &iucv_sock_ops;
 616                 break;
 617         case SOCK_SEQPACKET:
 618                 /* currently, proto ops can handle both sk types */
 619                 sock->ops = &iucv_sock_ops;
 620                 break;
 621         default:
 622                 return -ESOCKTNOSUPPORT;
 623         }
 624
 625         sk = iucv_sock_alloc(sock, protocol, GFP_KERNEL, kern);
 626         if (!sk)
 627                 return -ENOMEM;
 628
 629         iucv_sock_init(sk, NULL);
 630
 631         return 0;
 632 }
 633
 634 void iucv_sock_link(struct iucv_sock_list *l, struct sock *sk)
 635 {
 636         write_lock_bh(&l->lock);
 637         sk_add_node(sk, &l->head);
 638         write_unlock_bh(&l->lock);
 639 }
 640
 641 void iucv_sock_unlink(struct iucv_sock_list *l, struct sock *sk)
 642 {
 643         write_lock_bh(&l->lock);
 644         sk_del_node_init(sk);
 645         write_unlock_bh(&l->lock);
 646 }
 647
 648 void iucv_accept_enqueue(struct sock *parent, struct sock *sk)
 649 {
 650         unsigned long flags;
 651         struct iucv_sock *par = iucv_sk(parent);
 652
 653         sock_hold(sk);
 654         spin_lock_irqsave(&par->accept_q_lock, flags);
 655         list_add_tail(&iucv_sk(sk)->accept_q, &par->accept_q);
 656         spin_unlock_irqrestore(&par->accept_q_lock, flags);
 657         iucv_sk(sk)->parent = parent;
 658         sk_acceptq_added(parent);
 659 }
 660
 661 void iucv_accept_unlink(struct sock *sk)
 662 {
 663         unsigned long flags;
 664         struct iucv_sock *par = iucv_sk(iucv_sk(sk)->parent);
 665
 666         spin_lock_irqsave(&par->accept_q_lock, flags);
 667         list_del_init(&iucv_sk(sk)->accept_q);
 668         spin_unlock_irqrestore(&par->accept_q_lock, flags);
 669         sk_acceptq_removed(iucv_sk(sk)->parent);
 670         iucv_sk(sk)->parent = NULL;
 671         sock_put(sk);
 672 }
 673
 674 struct sock *iucv_accept_dequeue(struct sock *parent, struct socket *newsock)
 675 {
 676         struct iucv_sock *isk, *n;
 677         struct sock *sk;
 678
 679         list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
 680                 sk = (struct sock *) isk;
 681                 lock_sock(sk);
 682
 683                 if (sk->sk_state == IUCV_CLOSED) {
 684                         iucv_accept_unlink(sk);
 685                         release_sock(sk);
 686                         continue;
 687                 }
 688
 689                 if (sk->sk_state == IUCV_CONNECTED ||
 690                     sk->sk_state == IUCV_DISCONN ||
 691                     !newsock) {
 692                         iucv_accept_unlink(sk);
 693                         if (newsock)
 694                                 sock_graft(sk, newsock);
 695
 696                         release_sock(sk);
 697                         return sk;
 698                 }
 699
 700                 release_sock(sk);
 701         }
 702         return NULL;
 703 }
 704
 705 static void __iucv_auto_name(struct iucv_sock *iucv)
 706 {
 707         char name[12];
 708
 709         sprintf(name, "%08x", atomic_inc_return(&iucv_sk_list.autobind_name));
 710         while (__iucv_get_sock_by_name(name)) {
 711                 sprintf(name, "%08x",
 712                         atomic_inc_return(&iucv_sk_list.autobind_name));
 713         }
 714         memcpy(iucv->src_name, name, 8);
 715 }
 716
 717 /* Bind an unbound socket */
 718 static int iucv_sock_bind(struct socket *sock, struct sockaddr *addr,
 719                           int addr_len)
 720 {
 721         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
 722         struct sock *sk = sock->sk;
 723         struct iucv_sock *iucv;
 724         int err = 0;
 725         struct net_device *dev;
 726         char uid[9];
 727
 728         /* Verify the input sockaddr */
 729         if (addr_len < sizeof(struct sockaddr_iucv) ||
 730             addr->sa_family != AF_IUCV)
 731                 return -EINVAL;
 732
 733         lock_sock(sk);
 734         if (sk->sk_state != IUCV_OPEN) {
 735                 err = -EBADFD;
 736                 goto done;
 737         }
 738
 739         write_lock_bh(&iucv_sk_list.lock);
 740
 741         iucv = iucv_sk(sk);
 742         if (__iucv_get_sock_by_name(sa->siucv_name)) {
 743                 err = -EADDRINUSE;
 744                 goto done_unlock;
 745         }
 746         if (iucv->path)
 747                 goto done_unlock;
 748
 749         /* Bind the socket */
 750         if (pr_iucv)
 751                 if (!memcmp(sa->siucv_user_id, iucv_userid, 8))
 752                         goto vm_bind; /* VM IUCV transport */
 753
 754         /* try hiper transport */
 755         memcpy(uid, sa->siucv_user_id, sizeof(uid));
 756         ASCEBC(uid, 8);
 757         rcu_read_lock();
 758         for_each_netdev_rcu(&init_net, dev) {
 759                 if (!memcmp(dev->perm_addr, uid, 8)) {
 760                         memcpy(iucv->src_user_id, sa->siucv_user_id, 8);
 761                         /* Check for unitialized siucv_name */
 762                         if (strncmp(sa->siucv_name, "        ", 8) == 0)
 763                                 __iucv_auto_name(iucv);
 764                         else
 765                                 memcpy(iucv->src_name, sa->siucv_name, 8);
 766                         sk->sk_bound_dev_if = dev->ifindex;
 767                         iucv->hs_dev = dev;
 768                         dev_hold(dev);
 769                         sk->sk_state = IUCV_BOUND;
 770                         iucv->transport = AF_IUCV_TRANS_HIPER;
 771                         if (!iucv->msglimit)
 772                                 iucv->msglimit = IUCV_HIPER_MSGLIM_DEFAULT;
 773                         rcu_read_unlock();
 774                         goto done_unlock;
 775                 }
 776         }
 777         rcu_read_unlock();
 778 vm_bind:
 779         if (pr_iucv) {
 780                 /* use local userid for backward compat */
 781                 memcpy(iucv->src_name, sa->siucv_name, 8);
 782                 memcpy(iucv->src_user_id, iucv_userid, 8);
 783                 sk->sk_state = IUCV_BOUND;
 784                 iucv->transport = AF_IUCV_TRANS_IUCV;
 785                 if (!iucv->msglimit)
 786                         iucv->msglimit = IUCV_QUEUELEN_DEFAULT;
 787                 goto done_unlock;
 788         }
 789         /* found no dev to bind */
 790         err = -ENODEV;
 791 done_unlock:
 792         /* Release the socket list lock */
 793         write_unlock_bh(&iucv_sk_list.lock);
 794 done:
 795         release_sock(sk);
 796         return err;
 797 }
 798
 799 /* Automatically bind an unbound socket */
 800 static int iucv_sock_autobind(struct sock *sk)
 801 {
 802         struct iucv_sock *iucv = iucv_sk(sk);
 803         int err = 0;
 804
 805         if (unlikely(!pr_iucv))
 806                 return -EPROTO;
 807
 808         memcpy(iucv->src_user_id, iucv_userid, 8);
 809
 810         write_lock_bh(&iucv_sk_list.lock);
 811         __iucv_auto_name(iucv);
 812         write_unlock_bh(&iucv_sk_list.lock);
 813
 814         if (!iucv->msglimit)
 815                 iucv->msglimit = IUCV_QUEUELEN_DEFAULT;
 816
 817         return err;
 818 }
 819
 820 static int afiucv_path_connect(struct socket *sock, struct sockaddr *addr)
 821 {
 822         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
 823         struct sock *sk = sock->sk;
 824         struct iucv_sock *iucv = iucv_sk(sk);
 825         unsigned char user_data[16];
 826         int err;
 827
 828         high_nmcpy(user_data, sa->siucv_name);
 829         low_nmcpy(user_data, iucv->src_name);
 830         ASCEBC(user_data, sizeof(user_data));
 831
 832         /* Create path. */
 833         iucv->path = iucv_path_alloc(iucv->msglimit,
 834                                      IUCV_IPRMDATA, GFP_KERNEL);
 835         if (!iucv->path) {
 836                 err = -ENOMEM;
 837                 goto done;
 838         }
 839         err = pr_iucv->path_connect(iucv->path, &af_iucv_handler,
 840                                     sa->siucv_user_id, NULL, user_data,
 841                                     sk);
 842         if (err) {
 843                 iucv_path_free(iucv->path);
 844                 iucv->path = NULL;
 845                 switch (err) {
 846                 case 0x0b:      /* Target communicator is not logged on */
 847                         err = -ENETUNREACH;
 848                         break;
 849                 case 0x0d:      /* Max connections for this guest exceeded */
 850                 case 0x0e:      /* Max connections for target guest exceeded */
 851                         err = -EAGAIN;
 852                         break;
 853                 case 0x0f:      /* Missing IUCV authorization */
 854                         err = -EACCES;
 855                         break;
 856                 default:
 857                         err = -ECONNREFUSED;
 858                         break;
 859                 }
 860         }
 861 done:
 862         return err;
 863 }
 864
 865 /* Connect an unconnected socket */
 866 static int iucv_sock_connect(struct socket *sock, struct sockaddr *addr,
 867                              int alen, int flags)
 868 {
 869         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
 870         struct sock *sk = sock->sk;
 871         struct iucv_sock *iucv = iucv_sk(sk);
 872         int err;
 873
 874         if (alen < sizeof(struct sockaddr_iucv) || addr->sa_family != AF_IUCV)
 875                 return -EINVAL;
 876
 877         if (sk->sk_state != IUCV_OPEN && sk->sk_state != IUCV_BOUND)
 878                 return -EBADFD;
 879
 880         if (sk->sk_state == IUCV_OPEN &&
 881             iucv->transport == AF_IUCV_TRANS_HIPER)
 882                 return -EBADFD; /* explicit bind required */
 883
 884         if (sk->sk_type != SOCK_STREAM && sk->sk_type != SOCK_SEQPACKET)
 885                 return -EINVAL;
 886
 887         if (sk->sk_state == IUCV_OPEN) {
 888                 err = iucv_sock_autobind(sk);
 889                 if (unlikely(err))
 890                         return err;
 891         }
 892
 893         lock_sock(sk);
 894
 895         /* Set the destination information */
 896         memcpy(iucv->dst_user_id, sa->siucv_user_id, 8);
 897         memcpy(iucv->dst_name, sa->siucv_name, 8);
 898
 899         if (iucv->transport == AF_IUCV_TRANS_HIPER)
 900                 err = iucv_send_ctrl(sock->sk, AF_IUCV_FLAG_SYN);
 901         else
 902                 err = afiucv_path_connect(sock, addr);
 903         if (err)
 904                 goto done;
 905
 906         if (sk->sk_state != IUCV_CONNECTED)
 907                 err = iucv_sock_wait(sk, iucv_sock_in_state(sk, IUCV_CONNECTED,
 908                                                             IUCV_DISCONN),
 909                                      sock_sndtimeo(sk, flags & O_NONBLOCK));
 910
 911         if (sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_CLOSED)
 912                 err = -ECONNREFUSED;
 913
 914         if (err && iucv->transport == AF_IUCV_TRANS_IUCV)
 915                 iucv_sever_path(sk, 0);
 916
 917 done:
 918         release_sock(sk);
 919         return err;
 920 }
 921
 922 /* Move a socket into listening state. */
 923 static int iucv_sock_listen(struct socket *sock, int backlog)
 924 {
 925         struct sock *sk = sock->sk;
 926         int err;
 927
 928         lock_sock(sk);
 929
 930         err = -EINVAL;
 931         if (sk->sk_state != IUCV_BOUND)
 932                 goto done;
 933
 934         if (sock->type != SOCK_STREAM && sock->type != SOCK_SEQPACKET)
 935                 goto done;
 936
 937         sk->sk_max_ack_backlog = backlog;
 938         sk->sk_ack_backlog = 0;
 939         sk->sk_state = IUCV_LISTEN;
 940         err = 0;
 941
 942 done:
 943         release_sock(sk);
 944         return err;
 945 }
 946
 947 /* Accept a pending connection */
 948 static int iucv_sock_accept(struct socket *sock, struct socket *newsock,
 949                             int flags, bool kern)
 950 {
 951         DECLARE_WAITQUEUE(wait, current);
 952         struct sock *sk = sock->sk, *nsk;
 953         long timeo;
 954         int err = 0;
 955
 956         lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
 957
 958         if (sk->sk_state != IUCV_LISTEN) {
 959                 err = -EBADFD;
 960                 goto done;
 961         }
 962
 963         timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
 964
 965         /* Wait for an incoming connection */
 966         add_wait_queue_exclusive(sk_sleep(sk), &wait);
 967         while (!(nsk = iucv_accept_dequeue(sk, newsock))) {
 968                 set_current_state(TASK_INTERRUPTIBLE);
 969                 if (!timeo) {
 970                         err = -EAGAIN;
 971                         break;
 972                 }
 973
 974                 release_sock(sk);
 975                 timeo = schedule_timeout(timeo);
 976                 lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
 977
 978                 if (sk->sk_state != IUCV_LISTEN) {
 979                         err = -EBADFD;
 980                         break;
 981                 }
 982
 983                 if (signal_pending(current)) {
 984                         err = sock_intr_errno(timeo);
 985                         break;
 986                 }
 987         }
 988
 989         set_current_state(TASK_RUNNING);
 990         remove_wait_queue(sk_sleep(sk), &wait);
 991
 992         if (err)
 993                 goto done;
 994
 995         newsock->state = SS_CONNECTED;
 996
 997 done:
 998         release_sock(sk);
 999         return err;
1000 }
1001
1002 static int iucv_sock_getname(struct socket *sock, struct sockaddr *addr,
1003                              int peer)
1004 {
1005         struct sockaddr_iucv *siucv = (struct sockaddr_iucv *) addr;
1006         struct sock *sk = sock->sk;
1007         struct iucv_sock *iucv = iucv_sk(sk);
1008
1009         addr->sa_family = AF_IUCV;
1010
1011         if (peer) {
1012                 memcpy(siucv->siucv_user_id, iucv->dst_user_id, 8);
1013                 memcpy(siucv->siucv_name, iucv->dst_name, 8);
1014         } else {
1015                 memcpy(siucv->siucv_user_id, iucv->src_user_id, 8);
1016                 memcpy(siucv->siucv_name, iucv->src_name, 8);
1017         }
1018         memset(&siucv->siucv_port, 0, sizeof(siucv->siucv_port));
1019         memset(&siucv->siucv_addr, 0, sizeof(siucv->siucv_addr));
1020         memset(&siucv->siucv_nodeid, 0, sizeof(siucv->siucv_nodeid));
1021
1022         return sizeof(struct sockaddr_iucv);
1023 }
1024
1025 /**
1026  * iucv_send_iprm() - Send socket data in parameter list of an iucv message.
1027  * @path:       IUCV path
1028  * @msg:        Pointer to a struct iucv_message
1029  * @skb:        The socket data to send, skb->len MUST BE <= 7
1030  *
1031  * Send the socket data in the parameter list in the iucv message
1032  * (IUCV_IPRMDATA). The socket data is stored at index 0 to 6 in the parameter
1033  * list and the socket data len at index 7 (last byte).
1034  * See also iucv_msg_length().
1035  *
1036  * Returns the error code from the iucv_message_send() call.
1037  */
1038 static int iucv_send_iprm(struct iucv_path *path, struct iucv_message *msg,
1039                           struct sk_buff *skb)
1040 {
1041         u8 prmdata[8];
1042
1043         memcpy(prmdata, (void *) skb->data, skb->len);
1044         prmdata[7] = 0xff - (u8) skb->len;
1045         return pr_iucv->message_send(path, msg, IUCV_IPRMDATA, 0,
1046                                  (void *) prmdata, 8);
1047 }
1048
1049 static int iucv_sock_sendmsg(struct socket *sock, struct msghdr *msg,
1050                              size_t len)
1051 {
1052         struct sock *sk = sock->sk;
1053         struct iucv_sock *iucv = iucv_sk(sk);
1054         size_t headroom = 0;
1055         size_t linear;
1056         struct sk_buff *skb;
1057         struct iucv_message txmsg = {0};
1058         struct cmsghdr *cmsg;
1059         int cmsg_done;
1060         long timeo;
1061         char user_id[9];
1062         char appl_id[9];
1063         int err;
1064         int noblock = msg->msg_flags & MSG_DONTWAIT;
1065
1066         err = sock_error(sk);
1067         if (err)
1068                 return err;
1069
1070         if (msg->msg_flags & MSG_OOB)
1071                 return -EOPNOTSUPP;
1072
1073         /* SOCK_SEQPACKET: we do not support segmented records */
1074         if (sk->sk_type == SOCK_SEQPACKET && !(msg->msg_flags & MSG_EOR))
1075                 return -EOPNOTSUPP;
1076
1077         lock_sock(sk);
1078
1079         if (sk->sk_shutdown & SEND_SHUTDOWN) {
1080                 err = -EPIPE;
1081                 goto out;
1082         }
1083
1084         /* Return if the socket is not in connected state */
1085         if (sk->sk_state != IUCV_CONNECTED) {
1086                 err = -ENOTCONN;
1087                 goto out;
1088         }
1089
1090         /* initialize defaults */
1091         cmsg_done   = 0;        /* check for duplicate headers */
1092         txmsg.class = 0;
1093
1094         /* iterate over control messages */
1095         for_each_cmsghdr(cmsg, msg) {
1096                 if (!CMSG_OK(msg, cmsg)) {
1097                         err = -EINVAL;
1098                         goto out;
1099                 }
1100
1101                 if (cmsg->cmsg_level != SOL_IUCV)
1102                         continue;
1103
1104                 if (cmsg->cmsg_type & cmsg_done) {
1105                         err = -EINVAL;
1106                         goto out;
1107                 }
1108                 cmsg_done |= cmsg->cmsg_type;
1109
1110                 switch (cmsg->cmsg_type) {
1111                 case SCM_IUCV_TRGCLS:
1112                         if (cmsg->cmsg_len != CMSG_LEN(TRGCLS_SIZE)) {
1113                                 err = -EINVAL;
1114                                 goto out;
1115                         }
1116
1117                         /* set iucv message target class */
1118                         memcpy(&txmsg.class,
1119                                 (void *) CMSG_DATA(cmsg), TRGCLS_SIZE);
1120
1121                         break;
1122
1123                 default:
1124                         err = -EINVAL;
1125                         goto out;
1126                 }
1127         }
1128
1129         /* allocate one skb for each iucv message:
1130          * this is fine for SOCK_SEQPACKET (unless we want to support
1131          * segmented records using the MSG_EOR flag), but
1132          * for SOCK_STREAM we might want to improve it in future */
1133         if (iucv->transport == AF_IUCV_TRANS_HIPER) {
1134                 headroom = sizeof(struct af_iucv_trans_hdr) + ETH_HLEN;
1135                 linear = len;
1136         } else {
1137                 if (len < PAGE_SIZE) {
1138                         linear = len;
1139                 } else {
1140                         /* In nonlinear "classic" iucv skb,
1141                          * reserve space for iucv_array
1142                          */
1143                         headroom = sizeof(struct iucv_array) *
1144                                    (MAX_SKB_FRAGS + 1);
1145                         linear = PAGE_SIZE - headroom;
1146                 }
1147         }
1148         skb = sock_alloc_send_pskb(sk, headroom + linear, len - linear,
1149                                    noblock, &err, 0);
1150         if (!skb)
1151                 goto out;
1152         if (headroom)
1153                 skb_reserve(skb, headroom);
1154         skb_put(skb, linear);
1155         skb->len = len;
1156         skb->data_len = len - linear;
1157         err = skb_copy_datagram_from_iter(skb, 0, &msg->msg_iter, len);
1158         if (err)
1159                 goto fail;
1160
1161         /* wait if outstanding messages for iucv path has reached */
1162         timeo = sock_sndtimeo(sk, noblock);
1163         err = iucv_sock_wait(sk, iucv_below_msglim(sk), timeo);
1164         if (err)
1165                 goto fail;
1166
1167         /* return -ECONNRESET if the socket is no longer connected */
1168         if (sk->sk_state != IUCV_CONNECTED) {
1169                 err = -ECONNRESET;
1170                 goto fail;
1171         }
1172
1173         /* increment and save iucv message tag for msg_completion cbk */
1174         txmsg.tag = iucv->send_tag++;
1175         IUCV_SKB_CB(skb)->tag = txmsg.tag;
1176
1177         if (iucv->transport == AF_IUCV_TRANS_HIPER) {
1178                 atomic_inc(&iucv->msg_sent);
1179                 err = afiucv_hs_send(&txmsg, sk, skb, 0);
1180                 if (err) {
1181                         atomic_dec(&iucv->msg_sent);
1182                         goto out;
1183                 }
1184         } else { /* Classic VM IUCV transport */
1185                 skb_queue_tail(&iucv->send_skb_q, skb);
1186
1187                 if (((iucv->path->flags & IUCV_IPRMDATA) & iucv->flags) &&
1188                     skb->len <= 7) {
1189                         err = iucv_send_iprm(iucv->path, &txmsg, skb);
1190
1191                         /* on success: there is no message_complete callback */
1192                         /* for an IPRMDATA msg; remove skb from send queue   */
1193                         if (err == 0) {
1194                                 skb_unlink(skb, &iucv->send_skb_q);
1195                                 kfree_skb(skb);
1196                         }
1197
1198                         /* this error should never happen since the     */
1199                         /* IUCV_IPRMDATA path flag is set... sever path */
1200                         if (err == 0x15) {
1201                                 pr_iucv->path_sever(iucv->path, NULL);
1202                                 skb_unlink(skb, &iucv->send_skb_q);
1203                                 err = -EPIPE;
1204                                 goto fail;
1205                         }
1206                 } else if (skb_is_nonlinear(skb)) {
1207                         struct iucv_array *iba = (struct iucv_array *)skb->head;
1208                         int i;
1209
1210                         /* skip iucv_array lying in the headroom */
1211                         iba[0].address = (u32)(addr_t)skb->data;
1212                         iba[0].length = (u32)skb_headlen(skb);
1213                         for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1214                                 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
1215
1216                                 iba[i + 1].address =
1217                                         (u32)(addr_t)skb_frag_address(frag);
1218                                 iba[i + 1].length = (u32)skb_frag_size(frag);
1219                         }
1220                         err = pr_iucv->message_send(iucv->path, &txmsg,
1221                                                     IUCV_IPBUFLST, 0,
1222                                                     (void *)iba, skb->len);
1223                 } else { /* non-IPRM Linear skb */
1224                         err = pr_iucv->message_send(iucv->path, &txmsg,
1225                                         0, 0, (void *)skb->data, skb->len);
1226                 }
1227                 if (err) {
1228                         if (err == 3) {
1229                                 user_id[8] = 0;
1230                                 memcpy(user_id, iucv->dst_user_id, 8);
1231                                 appl_id[8] = 0;
1232                                 memcpy(appl_id, iucv->dst_name, 8);
1233                                 pr_err(
1234                 "Application %s on z/VM guest %s exceeds message limit\n",
1235                                         appl_id, user_id);
1236                                 err = -EAGAIN;
1237                         } else {
1238                                 err = -EPIPE;
1239                         }
1240                         skb_unlink(skb, &iucv->send_skb_q);
1241                         goto fail;
1242                 }
1243         }
1244
1245         release_sock(sk);
1246         return len;
1247
1248 fail:
1249         kfree_skb(skb);
1250 out:
1251         release_sock(sk);
1252         return err;
1253 }
1254
1255 static struct sk_buff *alloc_iucv_recv_skb(unsigned long len)
1256 {
1257         size_t headroom, linear;
1258         struct sk_buff *skb;
1259         int err;
1260
1261         if (len < PAGE_SIZE) {
1262                 headroom = 0;
1263                 linear = len;
1264         } else {
1265                 headroom = sizeof(struct iucv_array) * (MAX_SKB_FRAGS + 1);
1266                 linear = PAGE_SIZE - headroom;
1267         }
1268         skb = alloc_skb_with_frags(headroom + linear, len - linear,
1269                                    0, &err, GFP_ATOMIC | GFP_DMA);
1270         WARN_ONCE(!skb,
1271                   "alloc of recv iucv skb len=%lu failed with errcode=%d\n",
1272                   len, err);
1273         if (skb) {
1274                 if (headroom)
1275                         skb_reserve(skb, headroom);
1276                 skb_put(skb, linear);
1277                 skb->len = len;
1278                 skb->data_len = len - linear;
1279         }
1280         return skb;
1281 }
1282
1283 /* iucv_process_message() - Receive a single outstanding IUCV message
1284  *
1285  * Locking: must be called with message_q.lock held
1286  */
1287 static void iucv_process_message(struct sock *sk, struct sk_buff *skb,
1288                                  struct iucv_path *path,
1289                                  struct iucv_message *msg)
1290 {
1291         int rc;
1292         unsigned int len;
1293
1294         len = iucv_msg_length(msg);
1295
1296         /* store msg target class in the second 4 bytes of skb ctrl buffer */
1297         /* Note: the first 4 bytes are reserved for msg tag */
1298         IUCV_SKB_CB(skb)->class = msg->class;
1299
1300         /* check for special IPRM messages (e.g. iucv_sock_shutdown) */
1301         if ((msg->flags & IUCV_IPRMDATA) && len > 7) {
1302                 if (memcmp(msg->rmmsg, iprm_shutdown, 8) == 0) {
1303                         skb->data = NULL;
1304                         skb->len = 0;
1305                 }
1306         } else {
1307                 if (skb_is_nonlinear(skb)) {
1308                         struct iucv_array *iba = (struct iucv_array *)skb->head;
1309                         int i;
1310
1311                         iba[0].address = (u32)(addr_t)skb->data;
1312                         iba[0].length = (u32)skb_headlen(skb);
1313                         for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1314                                 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
1315
1316                                 iba[i + 1].address =
1317                                         (u32)(addr_t)skb_frag_address(frag);
1318                                 iba[i + 1].length = (u32)skb_frag_size(frag);
1319                         }
1320                         rc = pr_iucv->message_receive(path, msg,
1321                                               IUCV_IPBUFLST,
1322                                               (void *)iba, len, NULL);
1323                 } else {
1324                         rc = pr_iucv->message_receive(path, msg,
1325                                               msg->flags & IUCV_IPRMDATA,
1326                                               skb->data, len, NULL);
1327                 }
1328                 if (rc) {
1329                         kfree_skb(skb);
1330                         return;
1331                 }
1332                 WARN_ON_ONCE(skb->len != len);
1333         }
1334
1335         IUCV_SKB_CB(skb)->offset = 0;
1336         if (sk_filter(sk, skb)) {
1337                 atomic_inc(&sk->sk_drops);      /* skb rejected by filter */
1338                 kfree_skb(skb);
1339                 return;
1340         }
1341         if (__sock_queue_rcv_skb(sk, skb))      /* handle rcv queue full */
1342                 skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, skb);
1343 }
1344
1345 /* iucv_process_message_q() - Process outstanding IUCV messages
1346  *
1347  * Locking: must be called with message_q.lock held
1348  */
1349 static void iucv_process_message_q(struct sock *sk)
1350 {
1351         struct iucv_sock *iucv = iucv_sk(sk);
1352         struct sk_buff *skb;
1353         struct sock_msg_q *p, *n;
1354
1355         list_for_each_entry_safe(p, n, &iucv->message_q.list, list) {
1356                 skb = alloc_iucv_recv_skb(iucv_msg_length(&p->msg));
1357                 if (!skb)
1358                         break;
1359                 iucv_process_message(sk, skb, p->path, &p->msg);
1360                 list_del(&p->list);
1361                 kfree(p);
1362                 if (!skb_queue_empty(&iucv->backlog_skb_q))
1363                         break;
1364         }
1365 }
1366
1367 static int iucv_sock_recvmsg(struct socket *sock, struct msghdr *msg,
1368                              size_t len, int flags)
1369 {
1370         int noblock = flags & MSG_DONTWAIT;
1371         struct sock *sk = sock->sk;
1372         struct iucv_sock *iucv = iucv_sk(sk);
1373         unsigned int copied, rlen;
1374         struct sk_buff *skb, *rskb, *cskb;
1375         int err = 0;
1376         u32 offset;
1377
1378         if ((sk->sk_state == IUCV_DISCONN) &&
1379             skb_queue_empty(&iucv->backlog_skb_q) &&
1380             skb_queue_empty(&sk->sk_receive_queue) &&
1381             list_empty(&iucv->message_q.list))
1382                 return 0;
1383
1384         if (flags & (MSG_OOB))
1385                 return -EOPNOTSUPP;
1386
1387         /* receive/dequeue next skb:
1388          * the function understands MSG_PEEK and, thus, does not dequeue skb */
1389         skb = skb_recv_datagram(sk, flags, noblock, &err);
1390         if (!skb) {
1391                 if (sk->sk_shutdown & RCV_SHUTDOWN)
1392                         return 0;
1393                 return err;
1394         }
1395
1396         offset = IUCV_SKB_CB(skb)->offset;
1397         rlen   = skb->len - offset;             /* real length of skb */
1398         copied = min_t(unsigned int, rlen, len);
1399         if (!rlen)
1400                 sk->sk_shutdown = sk->sk_shutdown | RCV_SHUTDOWN;
1401
1402         cskb = skb;
1403         if (skb_copy_datagram_msg(cskb, offset, msg, copied)) {
1404                 if (!(flags & MSG_PEEK))
1405                         skb_queue_head(&sk->sk_receive_queue, skb);
1406                 return -EFAULT;
1407         }
1408
1409         /* SOCK_SEQPACKET: set MSG_TRUNC if recv buf size is too small */
1410         if (sk->sk_type == SOCK_SEQPACKET) {
1411                 if (copied < rlen)
1412                         msg->msg_flags |= MSG_TRUNC;
1413                 /* each iucv message contains a complete record */
1414                 msg->msg_flags |= MSG_EOR;
1415         }
1416
1417         /* create control message to store iucv msg target class:
1418          * get the trgcls from the control buffer of the skb due to
1419          * fragmentation of original iucv message. */
1420         err = put_cmsg(msg, SOL_IUCV, SCM_IUCV_TRGCLS,
1421                        sizeof(IUCV_SKB_CB(skb)->class),
1422                        (void *)&IUCV_SKB_CB(skb)->class);
1423         if (err) {
1424                 if (!(flags & MSG_PEEK))
1425                         skb_queue_head(&sk->sk_receive_queue, skb);
1426                 return err;
1427         }
1428
1429         /* Mark read part of skb as used */
1430         if (!(flags & MSG_PEEK)) {
1431
1432                 /* SOCK_STREAM: re-queue skb if it contains unreceived data */
1433                 if (sk->sk_type == SOCK_STREAM) {
1434                         if (copied < rlen) {
1435                                 IUCV_SKB_CB(skb)->offset = offset + copied;
1436                                 skb_queue_head(&sk->sk_receive_queue, skb);
1437                                 goto done;
1438                         }
1439                 }
1440
1441                 kfree_skb(skb);
1442                 if (iucv->transport == AF_IUCV_TRANS_HIPER) {
1443                         atomic_inc(&iucv->msg_recv);
1444                         if (atomic_read(&iucv->msg_recv) > iucv->msglimit) {
1445                                 WARN_ON(1);
1446                                 iucv_sock_close(sk);
1447                                 return -EFAULT;
1448                         }
1449                 }
1450
1451                 /* Queue backlog skbs */
1452                 spin_lock_bh(&iucv->message_q.lock);
1453                 rskb = skb_dequeue(&iucv->backlog_skb_q);
1454                 while (rskb) {
1455                         IUCV_SKB_CB(rskb)->offset = 0;
1456                         if (__sock_queue_rcv_skb(sk, rskb)) {
1457                                 /* handle rcv queue full */
1458                                 skb_queue_head(&iucv->backlog_skb_q,
1459                                                 rskb);
1460                                 break;
1461                         }
1462                         rskb = skb_dequeue(&iucv->backlog_skb_q);
1463                 }
1464                 if (skb_queue_empty(&iucv->backlog_skb_q)) {
1465                         if (!list_empty(&iucv->message_q.list))
1466                                 iucv_process_message_q(sk);
1467                         if (atomic_read(&iucv->msg_recv) >=
1468                                                         iucv->msglimit / 2) {
1469                                 err = iucv_send_ctrl(sk, AF_IUCV_FLAG_WIN);
1470                                 if (err) {
1471                                         sk->sk_state = IUCV_DISCONN;
1472                                         sk->sk_state_change(sk);
1473                                 }
1474                         }
1475                 }
1476                 spin_unlock_bh(&iucv->message_q.lock);
1477         }
1478
1479 done:
1480         /* SOCK_SEQPACKET: return real length if MSG_TRUNC is set */
1481         if (sk->sk_type == SOCK_SEQPACKET && (flags & MSG_TRUNC))
1482                 copied = rlen;
1483
1484         return copied;
1485 }
1486
1487 static inline __poll_t iucv_accept_poll(struct sock *parent)
1488 {
1489         struct iucv_sock *isk, *n;
1490         struct sock *sk;
1491
1492         list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
1493                 sk = (struct sock *) isk;
1494
1495                 if (sk->sk_state == IUCV_CONNECTED)
1496                         return EPOLLIN | EPOLLRDNORM;
1497         }
1498
1499         return 0;
1500 }
1501
1502 __poll_t iucv_sock_poll(struct file *file, struct socket *sock,
1503                             poll_table *wait)
1504 {
1505         struct sock *sk = sock->sk;
1506         __poll_t mask = 0;
1507
1508         sock_poll_wait(file, sock, wait);
1509
1510         if (sk->sk_state == IUCV_LISTEN)
1511                 return iucv_accept_poll(sk);
1512
1513         if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
1514                 mask |= EPOLLERR |
1515                         (sock_flag(sk, SOCK_SELECT_ERR_QUEUE) ? EPOLLPRI : 0);
1516
1517         if (sk->sk_shutdown & RCV_SHUTDOWN)
1518                 mask |= EPOLLRDHUP;
1519
1520         if (sk->sk_shutdown == SHUTDOWN_MASK)
1521                 mask |= EPOLLHUP;
1522
1523         if (!skb_queue_empty(&sk->sk_receive_queue) ||
1524             (sk->sk_shutdown & RCV_SHUTDOWN))
1525                 mask |= EPOLLIN | EPOLLRDNORM;
1526
1527         if (sk->sk_state == IUCV_CLOSED)
1528                 mask |= EPOLLHUP;
1529
1530         if (sk->sk_state == IUCV_DISCONN)
1531                 mask |= EPOLLIN;
1532
1533         if (sock_writeable(sk) && iucv_below_msglim(sk))
1534                 mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND;
1535         else
1536                 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1537
1538         return mask;
1539 }
1540
1541 static int iucv_sock_shutdown(struct socket *sock, int how)
1542 {
1543         struct sock *sk = sock->sk;
1544         struct iucv_sock *iucv = iucv_sk(sk);
1545         struct iucv_message txmsg;
1546         int err = 0;
1547
1548         how++;
1549
1550         if ((how & ~SHUTDOWN_MASK) || !how)
1551                 return -EINVAL;
1552
1553         lock_sock(sk);
1554         switch (sk->sk_state) {
1555         case IUCV_LISTEN:
1556         case IUCV_DISCONN:
1557         case IUCV_CLOSING:
1558         case IUCV_CLOSED:
1559                 err = -ENOTCONN;
1560                 goto fail;
1561         default:
1562                 break;
1563         }
1564
1565         if (how == SEND_SHUTDOWN || how == SHUTDOWN_MASK) {
1566                 if (iucv->transport == AF_IUCV_TRANS_IUCV) {
1567                         txmsg.class = 0;
1568                         txmsg.tag = 0;
1569                         err = pr_iucv->message_send(iucv->path, &txmsg,
1570                                 IUCV_IPRMDATA, 0, (void *) iprm_shutdown, 8);
1571                         if (err) {
1572                                 switch (err) {
1573                                 case 1:
1574                                         err = -ENOTCONN;
1575                                         break;
1576                                 case 2:
1577                                         err = -ECONNRESET;
1578                                         break;
1579                                 default:
1580                                         err = -ENOTCONN;
1581                                         break;
1582                                 }
1583                         }
1584                 } else
1585                         iucv_send_ctrl(sk, AF_IUCV_FLAG_SHT);
1586         }
1587
1588         sk->sk_shutdown |= how;
1589         if (how == RCV_SHUTDOWN || how == SHUTDOWN_MASK) {
1590                 if ((iucv->transport == AF_IUCV_TRANS_IUCV) &&
1591                     iucv->path) {
1592                         err = pr_iucv->path_quiesce(iucv->path, NULL);
1593                         if (err)
1594                                 err = -ENOTCONN;
1595 /*                      skb_queue_purge(&sk->sk_receive_queue); */
1596                 }
1597                 skb_queue_purge(&sk->sk_receive_queue);
1598         }
1599
1600         /* Wake up anyone sleeping in poll */
1601         sk->sk_state_change(sk);
1602
1603 fail:
1604         release_sock(sk);
1605         return err;
1606 }
1607
1608 static int iucv_sock_release(struct socket *sock)
1609 {
1610         struct sock *sk = sock->sk;
1611         int err = 0;
1612
1613         if (!sk)
1614                 return 0;
1615
1616         iucv_sock_close(sk);
1617
1618         sock_orphan(sk);
1619         iucv_sock_kill(sk);
1620         return err;
1621 }
1622
1623 /* getsockopt and setsockopt */
1624 static int iucv_sock_setsockopt(struct socket *sock, int level, int optname,
1625                                 char __user *optval, unsigned int optlen)
1626 {
1627         struct sock *sk = sock->sk;
1628         struct iucv_sock *iucv = iucv_sk(sk);
1629         int val;
1630         int rc;
1631
1632         if (level != SOL_IUCV)
1633                 return -ENOPROTOOPT;
1634
1635         if (optlen < sizeof(int))
1636                 return -EINVAL;
1637
1638         if (get_user(val, (int __user *) optval))
1639                 return -EFAULT;
1640
1641         rc = 0;
1642
1643         lock_sock(sk);
1644         switch (optname) {
1645         case SO_IPRMDATA_MSG:
1646                 if (val)
1647                         iucv->flags |= IUCV_IPRMDATA;
1648                 else
1649                         iucv->flags &= ~IUCV_IPRMDATA;
1650                 break;
1651         case SO_MSGLIMIT:
1652                 switch (sk->sk_state) {
1653                 case IUCV_OPEN:
1654                 case IUCV_BOUND:
1655                         if (val < 1 || val > (u16)(~0))
1656                                 rc = -EINVAL;
1657                         else
1658                                 iucv->msglimit = val;
1659                         break;
1660                 default:
1661                         rc = -EINVAL;
1662                         break;
1663                 }
1664                 break;
1665         default:
1666                 rc = -ENOPROTOOPT;
1667                 break;
1668         }
1669         release_sock(sk);
1670
1671         return rc;
1672 }
1673
1674 static int iucv_sock_getsockopt(struct socket *sock, int level, int optname,
1675                                 char __user *optval, int __user *optlen)
1676 {
1677         struct sock *sk = sock->sk;
1678         struct iucv_sock *iucv = iucv_sk(sk);
1679         unsigned int val;
1680         int len;
1681
1682         if (level != SOL_IUCV)
1683                 return -ENOPROTOOPT;
1684
1685         if (get_user(len, optlen))
1686                 return -EFAULT;
1687
1688         if (len < 0)
1689                 return -EINVAL;
1690
1691         len = min_t(unsigned int, len, sizeof(int));
1692
1693         switch (optname) {
1694         case SO_IPRMDATA_MSG:
1695                 val = (iucv->flags & IUCV_IPRMDATA) ? 1 : 0;
1696                 break;
1697         case SO_MSGLIMIT:
1698                 lock_sock(sk);
1699                 val = (iucv->path != NULL) ? iucv->path->msglim /* connected */
1700                                            : iucv->msglimit;    /* default */
1701                 release_sock(sk);
1702                 break;
1703         case SO_MSGSIZE:
1704                 if (sk->sk_state == IUCV_OPEN)
1705                         return -EBADFD;
1706                 val = (iucv->hs_dev) ? iucv->hs_dev->mtu -
1707                                 sizeof(struct af_iucv_trans_hdr) - ETH_HLEN :
1708                                 0x7fffffff;
1709                 break;
1710         default:
1711                 return -ENOPROTOOPT;
1712         }
1713
1714         if (put_user(len, optlen))
1715                 return -EFAULT;
1716         if (copy_to_user(optval, &val, len))
1717                 return -EFAULT;
1718
1719         return 0;
1720 }
1721
1722
1723 /* Callback wrappers - called from iucv base support */
1724 static int iucv_callback_connreq(struct iucv_path *path,
1725                                  u8 ipvmid[8], u8 ipuser[16])
1726 {
1727         unsigned char user_data[16];
1728         unsigned char nuser_data[16];
1729         unsigned char src_name[8];
1730         struct sock *sk, *nsk;
1731         struct iucv_sock *iucv, *niucv;
1732         int err;
1733
1734         memcpy(src_name, ipuser, 8);
1735         EBCASC(src_name, 8);
1736         /* Find out if this path belongs to af_iucv. */
1737         read_lock(&iucv_sk_list.lock);
1738         iucv = NULL;
1739         sk = NULL;
1740         sk_for_each(sk, &iucv_sk_list.head)
1741                 if (sk->sk_state == IUCV_LISTEN &&
1742                     !memcmp(&iucv_sk(sk)->src_name, src_name, 8)) {
1743                         /*
1744                          * Found a listening socket with
1745                          * src_name == ipuser[0-7].
1746                          */
1747                         iucv = iucv_sk(sk);
1748                         break;
1749                 }
1750         read_unlock(&iucv_sk_list.lock);
1751         if (!iucv)
1752                 /* No socket found, not one of our paths. */
1753                 return -EINVAL;
1754
1755         bh_lock_sock(sk);
1756
1757         /* Check if parent socket is listening */
1758         low_nmcpy(user_data, iucv->src_name);
1759         high_nmcpy(user_data, iucv->dst_name);
1760         ASCEBC(user_data, sizeof(user_data));
1761         if (sk->sk_state != IUCV_LISTEN) {
1762                 err = pr_iucv->path_sever(path, user_data);
1763                 iucv_path_free(path);
1764                 goto fail;
1765         }
1766
1767         /* Check for backlog size */
1768         if (sk_acceptq_is_full(sk)) {
1769                 err = pr_iucv->path_sever(path, user_data);
1770                 iucv_path_free(path);
1771                 goto fail;
1772         }
1773
1774         /* Create the new socket */
1775         nsk = iucv_sock_alloc(NULL, sk->sk_type, GFP_ATOMIC, 0);
1776         if (!nsk) {
1777                 err = pr_iucv->path_sever(path, user_data);
1778                 iucv_path_free(path);
1779                 goto fail;
1780         }
1781
1782         niucv = iucv_sk(nsk);
1783         iucv_sock_init(nsk, sk);
1784
1785         /* Set the new iucv_sock */
1786         memcpy(niucv->dst_name, ipuser + 8, 8);
1787         EBCASC(niucv->dst_name, 8);
1788         memcpy(niucv->dst_user_id, ipvmid, 8);
1789         memcpy(niucv->src_name, iucv->src_name, 8);
1790         memcpy(niucv->src_user_id, iucv->src_user_id, 8);
1791         niucv->path = path;
1792
1793         /* Call iucv_accept */
1794         high_nmcpy(nuser_data, ipuser + 8);
1795         memcpy(nuser_data + 8, niucv->src_name, 8);
1796         ASCEBC(nuser_data + 8, 8);
1797
1798         /* set message limit for path based on msglimit of accepting socket */
1799         niucv->msglimit = iucv->msglimit;
1800         path->msglim = iucv->msglimit;
1801         err = pr_iucv->path_accept(path, &af_iucv_handler, nuser_data, nsk);
1802         if (err) {
1803                 iucv_sever_path(nsk, 1);
1804                 iucv_sock_kill(nsk);
1805                 goto fail;
1806         }
1807
1808         iucv_accept_enqueue(sk, nsk);
1809
1810         /* Wake up accept */
1811         nsk->sk_state = IUCV_CONNECTED;
1812         sk->sk_data_ready(sk);
1813         err = 0;
1814 fail:
1815         bh_unlock_sock(sk);
1816         return 0;
1817 }
1818
1819 static void iucv_callback_connack(struct iucv_path *path, u8 ipuser[16])
1820 {
1821         struct sock *sk = path->private;
1822
1823         sk->sk_state = IUCV_CONNECTED;
1824         sk->sk_state_change(sk);
1825 }
1826
1827 static void iucv_callback_rx(struct iucv_path *path, struct iucv_message *msg)
1828 {
1829         struct sock *sk = path->private;
1830         struct iucv_sock *iucv = iucv_sk(sk);
1831         struct sk_buff *skb;
1832         struct sock_msg_q *save_msg;
1833         int len;
1834
1835         if (sk->sk_shutdown & RCV_SHUTDOWN) {
1836                 pr_iucv->message_reject(path, msg);
1837                 return;
1838         }
1839
1840         spin_lock(&iucv->message_q.lock);
1841
1842         if (!list_empty(&iucv->message_q.list) ||
1843             !skb_queue_empty(&iucv->backlog_skb_q))
1844                 goto save_message;
1845
1846         len = atomic_read(&sk->sk_rmem_alloc);
1847         len += SKB_TRUESIZE(iucv_msg_length(msg));
1848         if (len > sk->sk_rcvbuf)
1849                 goto save_message;
1850
1851         skb = alloc_iucv_recv_skb(iucv_msg_length(msg));
1852         if (!skb)
1853                 goto save_message;
1854
1855         iucv_process_message(sk, skb, path, msg);
1856         goto out_unlock;
1857
1858 save_message:
1859         save_msg = kzalloc(sizeof(struct sock_msg_q), GFP_ATOMIC | GFP_DMA);
1860         if (!save_msg)
1861                 goto out_unlock;
1862         save_msg->path = path;
1863         save_msg->msg = *msg;
1864
1865         list_add_tail(&save_msg->list, &iucv->message_q.list);
1866
1867 out_unlock:
1868         spin_unlock(&iucv->message_q.lock);
1869 }
1870
1871 static void iucv_callback_txdone(struct iucv_path *path,
1872                                  struct iucv_message *msg)
1873 {
1874         struct sock *sk = path->private;
1875         struct sk_buff *this = NULL;
1876         struct sk_buff_head *list = &iucv_sk(sk)->send_skb_q;
1877         struct sk_buff *list_skb;
1878         unsigned long flags;
1879
1880         bh_lock_sock(sk);
1881
1882         spin_lock_irqsave(&list->lock, flags);
1883         skb_queue_walk(list, list_skb) {
1884                 if (msg->tag == IUCV_SKB_CB(list_skb)->tag) {
1885                         this = list_skb;
1886                         break;
1887                 }
1888         }
1889         if (this)
1890                 __skb_unlink(this, list);
1891         spin_unlock_irqrestore(&list->lock, flags);
1892
1893         if (this) {
1894                 kfree_skb(this);
1895                 /* wake up any process waiting for sending */
1896                 iucv_sock_wake_msglim(sk);
1897         }
1898
1899         if (sk->sk_state == IUCV_CLOSING) {
1900                 if (skb_queue_empty(&iucv_sk(sk)->send_skb_q)) {
1901                         sk->sk_state = IUCV_CLOSED;
1902                         sk->sk_state_change(sk);
1903                 }
1904         }
1905         bh_unlock_sock(sk);
1906
1907 }
1908
1909 static void iucv_callback_connrej(struct iucv_path *path, u8 ipuser[16])
1910 {
1911         struct sock *sk = path->private;
1912
1913         if (sk->sk_state == IUCV_CLOSED)
1914                 return;
1915
1916         bh_lock_sock(sk);
1917         iucv_sever_path(sk, 1);
1918         sk->sk_state = IUCV_DISCONN;
1919
1920         sk->sk_state_change(sk);
1921         bh_unlock_sock(sk);
1922 }
1923
1924 /* called if the other communication side shuts down its RECV direction;
1925  * in turn, the callback sets SEND_SHUTDOWN to disable sending of data.
1926  */
1927 static void iucv_callback_shutdown(struct iucv_path *path, u8 ipuser[16])
1928 {
1929         struct sock *sk = path->private;
1930
1931         bh_lock_sock(sk);
1932         if (sk->sk_state != IUCV_CLOSED) {
1933                 sk->sk_shutdown |= SEND_SHUTDOWN;
1934                 sk->sk_state_change(sk);
1935         }
1936         bh_unlock_sock(sk);
1937 }
1938
1939 /***************** HiperSockets transport callbacks ********************/
1940 static void afiucv_swap_src_dest(struct sk_buff *skb)
1941 {
1942         struct af_iucv_trans_hdr *trans_hdr = iucv_trans_hdr(skb);
1943         char tmpID[8];
1944         char tmpName[8];
1945
1946         ASCEBC(trans_hdr->destUserID, sizeof(trans_hdr->destUserID));
1947         ASCEBC(trans_hdr->destAppName, sizeof(trans_hdr->destAppName));
1948         ASCEBC(trans_hdr->srcUserID, sizeof(trans_hdr->srcUserID));
1949         ASCEBC(trans_hdr->srcAppName, sizeof(trans_hdr->srcAppName));
1950         memcpy(tmpID, trans_hdr->srcUserID, 8);
1951         memcpy(tmpName, trans_hdr->srcAppName, 8);
1952         memcpy(trans_hdr->srcUserID, trans_hdr->destUserID, 8);
1953         memcpy(trans_hdr->srcAppName, trans_hdr->destAppName, 8);
1954         memcpy(trans_hdr->destUserID, tmpID, 8);
1955         memcpy(trans_hdr->destAppName, tmpName, 8);
1956         skb_push(skb, ETH_HLEN);
1957         memset(skb->data, 0, ETH_HLEN);
1958 }
1959
1960 /**
1961  * afiucv_hs_callback_syn - react on received SYN
1962  **/
1963 static int afiucv_hs_callback_syn(struct sock *sk, struct sk_buff *skb)
1964 {
1965         struct af_iucv_trans_hdr *trans_hdr = iucv_trans_hdr(skb);
1966         struct sock *nsk;
1967         struct iucv_sock *iucv, *niucv;
1968         int err;
1969
1970         iucv = iucv_sk(sk);
1971         if (!iucv) {
1972                 /* no sock - connection refused */
1973                 afiucv_swap_src_dest(skb);
1974                 trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN;
1975                 err = dev_queue_xmit(skb);
1976                 goto out;
1977         }
1978
1979         nsk = iucv_sock_alloc(NULL, sk->sk_type, GFP_ATOMIC, 0);
1980         bh_lock_sock(sk);
1981         if ((sk->sk_state != IUCV_LISTEN) ||
1982             sk_acceptq_is_full(sk) ||
1983             !nsk) {
1984                 /* error on server socket - connection refused */
1985                 afiucv_swap_src_dest(skb);
1986                 trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN;
1987                 err = dev_queue_xmit(skb);
1988                 iucv_sock_kill(nsk);
1989                 bh_unlock_sock(sk);
1990                 goto out;
1991         }
1992
1993         niucv = iucv_sk(nsk);
1994         iucv_sock_init(nsk, sk);
1995         niucv->transport = AF_IUCV_TRANS_HIPER;
1996         niucv->msglimit = iucv->msglimit;
1997         if (!trans_hdr->window)
1998                 niucv->msglimit_peer = IUCV_HIPER_MSGLIM_DEFAULT;
1999         else
2000                 niucv->msglimit_peer = trans_hdr->window;
2001         memcpy(niucv->dst_name, trans_hdr->srcAppName, 8);
2002         memcpy(niucv->dst_user_id, trans_hdr->srcUserID, 8);
2003         memcpy(niucv->src_name, iucv->src_name, 8);
2004         memcpy(niucv->src_user_id, iucv->src_user_id, 8);
2005         nsk->sk_bound_dev_if = sk->sk_bound_dev_if;
2006         niucv->hs_dev = iucv->hs_dev;
2007         dev_hold(niucv->hs_dev);
2008         afiucv_swap_src_dest(skb);
2009         trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_ACK;
2010         trans_hdr->window = niucv->msglimit;
2011         /* if receiver acks the xmit connection is established */
2012         err = dev_queue_xmit(skb);
2013         if (!err) {
2014                 iucv_accept_enqueue(sk, nsk);
2015                 nsk->sk_state = IUCV_CONNECTED;
2016                 sk->sk_data_ready(sk);
2017         } else
2018                 iucv_sock_kill(nsk);
2019         bh_unlock_sock(sk);
2020
2021 out:
2022         return NET_RX_SUCCESS;
2023 }
2024
2025 /**
2026  * afiucv_hs_callback_synack() - react on received SYN-ACK
2027  **/
2028 static int afiucv_hs_callback_synack(struct sock *sk, struct sk_buff *skb)
2029 {
2030         struct iucv_sock *iucv = iucv_sk(sk);
2031
2032         if (!iucv)
2033                 goto out;
2034         if (sk->sk_state != IUCV_BOUND)
2035                 goto out;
2036         bh_lock_sock(sk);
2037         iucv->msglimit_peer = iucv_trans_hdr(skb)->window;
2038         sk->sk_state = IUCV_CONNECTED;
2039         sk->sk_state_change(sk);
2040         bh_unlock_sock(sk);
2041 out:
2042         kfree_skb(skb);
2043         return NET_RX_SUCCESS;
2044 }
2045
2046 /**
2047  * afiucv_hs_callback_synfin() - react on received SYN_FIN
2048  **/
2049 static int afiucv_hs_callback_synfin(struct sock *sk, struct sk_buff *skb)
2050 {
2051         struct iucv_sock *iucv = iucv_sk(sk);
2052
2053         if (!iucv)
2054                 goto out;
2055         if (sk->sk_state != IUCV_BOUND)
2056                 goto out;
2057         bh_lock_sock(sk);
2058         sk->sk_state = IUCV_DISCONN;
2059         sk->sk_state_change(sk);
2060         bh_unlock_sock(sk);
2061 out:
2062         kfree_skb(skb);
2063         return NET_RX_SUCCESS;
2064 }
2065
2066 /**
2067  * afiucv_hs_callback_fin() - react on received FIN
2068  **/
2069 static int afiucv_hs_callback_fin(struct sock *sk, struct sk_buff *skb)
2070 {
2071         struct iucv_sock *iucv = iucv_sk(sk);
2072
2073         /* other end of connection closed */
2074         if (!iucv)
2075                 goto out;
2076         bh_lock_sock(sk);
2077         if (sk->sk_state == IUCV_CONNECTED) {
2078                 sk->sk_state = IUCV_DISCONN;
2079                 sk->sk_state_change(sk);
2080         }
2081         bh_unlock_sock(sk);
2082 out:
2083         kfree_skb(skb);
2084         return NET_RX_SUCCESS;
2085 }
2086
2087 /**
2088  * afiucv_hs_callback_win() - react on received WIN
2089  **/
2090 static int afiucv_hs_callback_win(struct sock *sk, struct sk_buff *skb)
2091 {
2092         struct iucv_sock *iucv = iucv_sk(sk);
2093
2094         if (!iucv)
2095                 return NET_RX_SUCCESS;
2096
2097         if (sk->sk_state != IUCV_CONNECTED)
2098                 return NET_RX_SUCCESS;
2099
2100         atomic_sub(iucv_trans_hdr(skb)->window, &iucv->msg_sent);
2101         iucv_sock_wake_msglim(sk);
2102         return NET_RX_SUCCESS;
2103 }
2104
2105 /**
2106  * afiucv_hs_callback_rx() - react on received data
2107  **/
2108 static int afiucv_hs_callback_rx(struct sock *sk, struct sk_buff *skb)
2109 {
2110         struct iucv_sock *iucv = iucv_sk(sk);
2111
2112         if (!iucv) {
2113                 kfree_skb(skb);
2114                 return NET_RX_SUCCESS;
2115         }
2116
2117         if (sk->sk_state != IUCV_CONNECTED) {
2118                 kfree_skb(skb);
2119                 return NET_RX_SUCCESS;
2120         }
2121
2122         if (sk->sk_shutdown & RCV_SHUTDOWN) {
2123                 kfree_skb(skb);
2124                 return NET_RX_SUCCESS;
2125         }
2126
2127         /* write stuff from iucv_msg to skb cb */
2128         skb_pull(skb, sizeof(struct af_iucv_trans_hdr));
2129         skb_reset_transport_header(skb);
2130         skb_reset_network_header(skb);
2131         IUCV_SKB_CB(skb)->offset = 0;
2132         if (sk_filter(sk, skb)) {
2133                 atomic_inc(&sk->sk_drops);      /* skb rejected by filter */
2134                 kfree_skb(skb);
2135                 return NET_RX_SUCCESS;
2136         }
2137
2138         spin_lock(&iucv->message_q.lock);
2139         if (skb_queue_empty(&iucv->backlog_skb_q)) {
2140                 if (__sock_queue_rcv_skb(sk, skb))
2141                         /* handle rcv queue full */
2142                         skb_queue_tail(&iucv->backlog_skb_q, skb);
2143         } else
2144                 skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, skb);
2145         spin_unlock(&iucv->message_q.lock);
2146         return NET_RX_SUCCESS;
2147 }
2148
2149 /**
2150  * afiucv_hs_rcv() - base function for arriving data through HiperSockets
2151  *                   transport
2152  *                   called from netif RX softirq
2153  **/
2154 static int afiucv_hs_rcv(struct sk_buff *skb, struct net_device *dev,
2155         struct packet_type *pt, struct net_device *orig_dev)
2156 {
2157         struct sock *sk;
2158         struct iucv_sock *iucv;
2159         struct af_iucv_trans_hdr *trans_hdr;
2160         int err = NET_RX_SUCCESS;
2161         char nullstring[8];
2162
2163         if (!pskb_may_pull(skb, sizeof(*trans_hdr))) {
2164                 WARN_ONCE(1, "AF_IUCV failed to receive skb, len=%u", skb->len);
2165                 kfree_skb(skb);
2166                 return NET_RX_SUCCESS;
2167         }
2168
2169         trans_hdr = iucv_trans_hdr(skb);
2170         EBCASC(trans_hdr->destAppName, sizeof(trans_hdr->destAppName));
2171         EBCASC(trans_hdr->destUserID, sizeof(trans_hdr->destUserID));
2172         EBCASC(trans_hdr->srcAppName, sizeof(trans_hdr->srcAppName));
2173         EBCASC(trans_hdr->srcUserID, sizeof(trans_hdr->srcUserID));
2174         memset(nullstring, 0, sizeof(nullstring));
2175         iucv = NULL;
2176         sk = NULL;
2177         read_lock(&iucv_sk_list.lock);
2178         sk_for_each(sk, &iucv_sk_list.head) {
2179                 if (trans_hdr->flags == AF_IUCV_FLAG_SYN) {
2180                         if ((!memcmp(&iucv_sk(sk)->src_name,
2181                                      trans_hdr->destAppName, 8)) &&
2182                             (!memcmp(&iucv_sk(sk)->src_user_id,
2183                                      trans_hdr->destUserID, 8)) &&
2184                             (!memcmp(&iucv_sk(sk)->dst_name, nullstring, 8)) &&
2185                             (!memcmp(&iucv_sk(sk)->dst_user_id,
2186                                      nullstring, 8))) {
2187                                 iucv = iucv_sk(sk);
2188                                 break;
2189                         }
2190                 } else {
2191                         if ((!memcmp(&iucv_sk(sk)->src_name,
2192                                      trans_hdr->destAppName, 8)) &&
2193                             (!memcmp(&iucv_sk(sk)->src_user_id,
2194                                      trans_hdr->destUserID, 8)) &&
2195                             (!memcmp(&iucv_sk(sk)->dst_name,
2196                                      trans_hdr->srcAppName, 8)) &&
2197                             (!memcmp(&iucv_sk(sk)->dst_user_id,
2198                                      trans_hdr->srcUserID, 8))) {
2199                                 iucv = iucv_sk(sk);
2200                                 break;
2201                         }
2202                 }
2203         }
2204         read_unlock(&iucv_sk_list.lock);
2205         if (!iucv)
2206                 sk = NULL;
2207
2208         /* no sock
2209         how should we send with no sock
2210         1) send without sock no send rc checking?
2211         2) introduce default sock to handle this cases
2212
2213          SYN -> send SYN|ACK in good case, send SYN|FIN in bad case
2214          data -> send FIN
2215          SYN|ACK, SYN|FIN, FIN -> no action? */
2216
2217         switch (trans_hdr->flags) {
2218         case AF_IUCV_FLAG_SYN:
2219                 /* connect request */
2220                 err = afiucv_hs_callback_syn(sk, skb);
2221                 break;
2222         case (AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_ACK):
2223                 /* connect request confirmed */
2224                 err = afiucv_hs_callback_synack(sk, skb);
2225                 break;
2226         case (AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN):
2227                 /* connect request refused */
2228                 err = afiucv_hs_callback_synfin(sk, skb);
2229                 break;
2230         case (AF_IUCV_FLAG_FIN):
2231                 /* close request */
2232                 err = afiucv_hs_callback_fin(sk, skb);
2233                 break;
2234         case (AF_IUCV_FLAG_WIN):
2235                 err = afiucv_hs_callback_win(sk, skb);
2236                 if (skb->len == sizeof(struct af_iucv_trans_hdr)) {
2237                         kfree_skb(skb);
2238                         break;
2239                 }
2240                 /* fall through and receive non-zero length data */
2241         case (AF_IUCV_FLAG_SHT):
2242                 /* shutdown request */
2243                 /* fall through and receive zero length data */
2244         case 0:
2245                 /* plain data frame */
2246                 IUCV_SKB_CB(skb)->class = trans_hdr->iucv_hdr.class;
2247                 err = afiucv_hs_callback_rx(sk, skb);
2248                 break;
2249         default:
2250                 kfree_skb(skb);
2251         }
2252
2253         return err;
2254 }
2255
2256 /**
2257  * afiucv_hs_callback_txnotify() - handle send notifcations from HiperSockets
2258  *                                 transport
2259  **/
2260 static void afiucv_hs_callback_txnotify(struct sk_buff *skb,
2261                                         enum iucv_tx_notify n)
2262 {
2263         struct sock *isk = skb->sk;
2264         struct sock *sk = NULL;
2265         struct iucv_sock *iucv = NULL;
2266         struct sk_buff_head *list;
2267         struct sk_buff *list_skb;
2268         struct sk_buff *nskb;
2269         unsigned long flags;
2270
2271         read_lock_irqsave(&iucv_sk_list.lock, flags);
2272         sk_for_each(sk, &iucv_sk_list.head)
2273                 if (sk == isk) {
2274                         iucv = iucv_sk(sk);
2275                         break;
2276                 }
2277         read_unlock_irqrestore(&iucv_sk_list.lock, flags);
2278
2279         if (!iucv || sock_flag(sk, SOCK_ZAPPED))
2280                 return;
2281
2282         list = &iucv->send_skb_q;
2283         spin_lock_irqsave(&list->lock, flags);
2284         skb_queue_walk_safe(list, list_skb, nskb) {
2285                 if (skb_shinfo(list_skb) == skb_shinfo(skb)) {
2286                         switch (n) {
2287                         case TX_NOTIFY_OK:
2288                                 __skb_unlink(list_skb, list);
2289                                 kfree_skb(list_skb);
2290                                 iucv_sock_wake_msglim(sk);
2291                                 break;
2292                         case TX_NOTIFY_PENDING:
2293                                 atomic_inc(&iucv->pendings);
2294                                 break;
2295                         case TX_NOTIFY_DELAYED_OK:
2296                                 __skb_unlink(list_skb, list);
2297                                 atomic_dec(&iucv->pendings);
2298                                 if (atomic_read(&iucv->pendings) <= 0)
2299                                         iucv_sock_wake_msglim(sk);
2300                                 kfree_skb(list_skb);
2301                                 break;
2302                         case TX_NOTIFY_UNREACHABLE:
2303                         case TX_NOTIFY_DELAYED_UNREACHABLE:
2304                         case TX_NOTIFY_TPQFULL: /* not yet used */
2305                         case TX_NOTIFY_GENERALERROR:
2306                         case TX_NOTIFY_DELAYED_GENERALERROR:
2307                                 __skb_unlink(list_skb, list);
2308                                 kfree_skb(list_skb);
2309                                 if (sk->sk_state == IUCV_CONNECTED) {
2310                                         sk->sk_state = IUCV_DISCONN;
2311                                         sk->sk_state_change(sk);
2312                                 }
2313                                 break;
2314                         }
2315                         break;
2316                 }
2317         }
2318         spin_unlock_irqrestore(&list->lock, flags);
2319
2320         if (sk->sk_state == IUCV_CLOSING) {
2321                 if (skb_queue_empty(&iucv_sk(sk)->send_skb_q)) {
2322                         sk->sk_state = IUCV_CLOSED;
2323                         sk->sk_state_change(sk);
2324                 }
2325         }
2326
2327 }
2328
2329 /*
2330  * afiucv_netdev_event: handle netdev notifier chain events
2331  */
2332 static int afiucv_netdev_event(struct notifier_block *this,
2333                                unsigned long event, void *ptr)
2334 {
2335         struct net_device *event_dev = netdev_notifier_info_to_dev(ptr);
2336         struct sock *sk;
2337         struct iucv_sock *iucv;
2338
2339         switch (event) {
2340         case NETDEV_REBOOT:
2341         case NETDEV_GOING_DOWN:
2342                 sk_for_each(sk, &iucv_sk_list.head) {
2343                         iucv = iucv_sk(sk);
2344                         if ((iucv->hs_dev == event_dev) &&
2345                             (sk->sk_state == IUCV_CONNECTED)) {
2346                                 if (event == NETDEV_GOING_DOWN)
2347                                         iucv_send_ctrl(sk, AF_IUCV_FLAG_FIN);
2348                                 sk->sk_state = IUCV_DISCONN;
2349                                 sk->sk_state_change(sk);
2350                         }
2351                 }
2352                 break;
2353         case NETDEV_DOWN:
2354         case NETDEV_UNREGISTER:
2355         default:
2356                 break;
2357         }
2358         return NOTIFY_DONE;
2359 }
2360
2361 static struct notifier_block afiucv_netdev_notifier = {
2362         .notifier_call = afiucv_netdev_event,
2363 };
2364
2365 static const struct proto_ops iucv_sock_ops = {
2366         .family         = PF_IUCV,
2367         .owner          = THIS_MODULE,
2368         .release        = iucv_sock_release,
2369         .bind           = iucv_sock_bind,
2370         .connect        = iucv_sock_connect,
2371         .listen         = iucv_sock_listen,
2372         .accept         = iucv_sock_accept,
2373         .getname        = iucv_sock_getname,
2374         .sendmsg        = iucv_sock_sendmsg,
2375         .recvmsg        = iucv_sock_recvmsg,
2376         .poll           = iucv_sock_poll,
2377         .ioctl          = sock_no_ioctl,
2378         .mmap           = sock_no_mmap,
2379         .socketpair     = sock_no_socketpair,
2380         .shutdown       = iucv_sock_shutdown,
2381         .setsockopt     = iucv_sock_setsockopt,
2382         .getsockopt     = iucv_sock_getsockopt,
2383 };
2384
2385 static const struct net_proto_family iucv_sock_family_ops = {
2386         .family = AF_IUCV,
2387         .owner  = THIS_MODULE,
2388         .create = iucv_sock_create,
2389 };
2390
2391 static struct packet_type iucv_packet_type = {
2392         .type = cpu_to_be16(ETH_P_AF_IUCV),
2393         .func = afiucv_hs_rcv,
2394 };
2395
2396 static int afiucv_iucv_init(void)
2397 {
2398         int err;
2399
2400         err = pr_iucv->iucv_register(&af_iucv_handler, 0);
2401         if (err)
2402                 goto out;
2403         /* establish dummy device */
2404         af_iucv_driver.bus = pr_iucv->bus;
2405         err = driver_register(&af_iucv_driver);
2406         if (err)
2407                 goto out_iucv;
2408         af_iucv_dev = kzalloc(sizeof(struct device), GFP_KERNEL);
2409         if (!af_iucv_dev) {
2410                 err = -ENOMEM;
2411                 goto out_driver;
2412         }
2413         dev_set_name(af_iucv_dev, "af_iucv");
2414         af_iucv_dev->bus = pr_iucv->bus;
2415         af_iucv_dev->parent = pr_iucv->root;
2416         af_iucv_dev->release = (void (*)(struct device *))kfree;
2417         af_iucv_dev->driver = &af_iucv_driver;
2418         err = device_register(af_iucv_dev);
2419         if (err)
2420                 goto out_iucv_dev;
2421         return 0;
2422
2423 out_iucv_dev:
2424         put_device(af_iucv_dev);
2425 out_driver:
2426         driver_unregister(&af_iucv_driver);
2427 out_iucv:
2428         pr_iucv->iucv_unregister(&af_iucv_handler, 0);
2429 out:
2430         return err;
2431 }
2432
2433 static int __init afiucv_init(void)
2434 {
2435         int err;
2436
2437         if (MACHINE_IS_VM) {
2438                 cpcmd("QUERY USERID", iucv_userid, sizeof(iucv_userid), &err);
2439                 if (unlikely(err)) {
2440                         WARN_ON(err);
2441                         err = -EPROTONOSUPPORT;
2442                         goto out;
2443                 }
2444
2445                 pr_iucv = try_then_request_module(symbol_get(iucv_if), "iucv");
2446                 if (!pr_iucv) {
2447                         printk(KERN_WARNING "iucv_if lookup failed\n");
2448                         memset(&iucv_userid, 0, sizeof(iucv_userid));
2449                 }
2450         } else {
2451                 memset(&iucv_userid, 0, sizeof(iucv_userid));
2452                 pr_iucv = NULL;
2453         }
2454
2455         err = proto_register(&iucv_proto, 0);
2456         if (err)
2457                 goto out;
2458         err = sock_register(&iucv_sock_family_ops);
2459         if (err)
2460                 goto out_proto;
2461
2462         if (pr_iucv) {
2463                 err = afiucv_iucv_init();
2464                 if (err)
2465                         goto out_sock;
2466         } else
2467                 register_netdevice_notifier(&afiucv_netdev_notifier);
2468         dev_add_pack(&iucv_packet_type);
2469         return 0;
2470
2471 out_sock:
2472         sock_unregister(PF_IUCV);
2473 out_proto:
2474         proto_unregister(&iucv_proto);
2475 out:
2476         if (pr_iucv)
2477                 symbol_put(iucv_if);
2478         return err;
2479 }
2480
2481 static void __exit afiucv_exit(void)
2482 {
2483         if (pr_iucv) {
2484                 device_unregister(af_iucv_dev);
2485                 driver_unregister(&af_iucv_driver);
2486                 pr_iucv->iucv_unregister(&af_iucv_handler, 0);
2487                 symbol_put(iucv_if);
2488         } else
2489                 unregister_netdevice_notifier(&afiucv_netdev_notifier);
2490         dev_remove_pack(&iucv_packet_type);
2491         sock_unregister(PF_IUCV);
2492         proto_unregister(&iucv_proto);
2493 }
2494
2495 module_init(afiucv_init);
2496 module_exit(afiucv_exit);
2497
2498 MODULE_AUTHOR("Jennifer Hunt <[email protected]>");
2499 MODULE_DESCRIPTION("IUCV Sockets ver " VERSION);
2500 MODULE_VERSION(VERSION);
2501 MODULE_LICENSE("GPL");
2502 MODULE_ALIAS_NETPROTO(PF_IUCV);