Pileus Git - ~andy/linux/blob - net/vmw_vsock/af_vsock.c

   1 /*
   2  * VMware vSockets Driver
   3  *
   4  * Copyright (C) 2007-2013 VMware, Inc. All rights reserved.
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License as published by the Free
   8  * Software Foundation version 2 and no later version.
   9  *
  10  * This program is distributed in the hope that it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14  */
  15
  16 /* Implementation notes:
  17  *
  18  * - There are two kinds of sockets: those created by user action (such as
  19  * calling socket(2)) and those created by incoming connection request packets.
  20  *
  21  * - There are two "global" tables, one for bound sockets (sockets that have
  22  * specified an address that they are responsible for) and one for connected
  23  * sockets (sockets that have established a connection with another socket).
  24  * These tables are "global" in that all sockets on the system are placed
  25  * within them. - Note, though, that the bound table contains an extra entry
  26  * for a list of unbound sockets and SOCK_DGRAM sockets will always remain in
  27  * that list. The bound table is used solely for lookup of sockets when packets
  28  * are received and that's not necessary for SOCK_DGRAM sockets since we create
  29  * a datagram handle for each and need not perform a lookup.  Keeping SOCK_DGRAM
  30  * sockets out of the bound hash buckets will reduce the chance of collisions
  31  * when looking for SOCK_STREAM sockets and prevents us from having to check the
  32  * socket type in the hash table lookups.
  33  *
  34  * - Sockets created by user action will either be "client" sockets that
  35  * initiate a connection or "server" sockets that listen for connections; we do
  36  * not support simultaneous connects (two "client" sockets connecting).
  37  *
  38  * - "Server" sockets are referred to as listener sockets throughout this
  39  * implementation because they are in the SS_LISTEN state.  When a connection
  40  * request is received (the second kind of socket mentioned above), we create a
  41  * new socket and refer to it as a pending socket.  These pending sockets are
  42  * placed on the pending connection list of the listener socket.  When future
  43  * packets are received for the address the listener socket is bound to, we
  44  * check if the source of the packet is from one that has an existing pending
  45  * connection.  If it does, we process the packet for the pending socket.  When
  46  * that socket reaches the connected state, it is removed from the listener
  47  * socket's pending list and enqueued in the listener socket's accept queue.
  48  * Callers of accept(2) will accept connected sockets from the listener socket's
  49  * accept queue.  If the socket cannot be accepted for some reason then it is
  50  * marked rejected.  Once the connection is accepted, it is owned by the user
  51  * process and the responsibility for cleanup falls with that user process.
  52  *
  53  * - It is possible that these pending sockets will never reach the connected
  54  * state; in fact, we may never receive another packet after the connection
  55  * request.  Because of this, we must schedule a cleanup function to run in the
  56  * future, after some amount of time passes where a connection should have been
  57  * established.  This function ensures that the socket is off all lists so it
  58  * cannot be retrieved, then drops all references to the socket so it is cleaned
  59  * up (sock_put() -> sk_free() -> our sk_destruct implementation).  Note this
  60  * function will also cleanup rejected sockets, those that reach the connected
  61  * state but leave it before they have been accepted.
  62  *
  63  * - Sockets created by user action will be cleaned up when the user process
  64  * calls close(2), causing our release implementation to be called. Our release
  65  * implementation will perform some cleanup then drop the last reference so our
  66  * sk_destruct implementation is invoked.  Our sk_destruct implementation will
  67  * perform additional cleanup that's common for both types of sockets.
  68  *
  69  * - A socket's reference count is what ensures that the structure won't be
  70  * freed.  Each entry in a list (such as the "global" bound and connected tables
  71  * and the listener socket's pending list and connected queue) ensures a
  72  * reference.  When we defer work until process context and pass a socket as our
  73  * argument, we must ensure the reference count is increased to ensure the
  74  * socket isn't freed before the function is run; the deferred function will
  75  * then drop the reference.
  76  */
  77
  78 #include <linux/types.h>
  79
  80 #define EXPORT_SYMTAB
  81 #include <linux/bitops.h>
  82 #include <linux/cred.h>
  83 #include <linux/init.h>
  84 #include <linux/io.h>
  85 #include <linux/kernel.h>
  86 #include <linux/kmod.h>
  87 #include <linux/list.h>
  88 #include <linux/miscdevice.h>
  89 #include <linux/module.h>
  90 #include <linux/mutex.h>
  91 #include <linux/net.h>
  92 #include <linux/poll.h>
  93 #include <linux/skbuff.h>
  94 #include <linux/smp.h>
  95 #include <linux/socket.h>
  96 #include <linux/stddef.h>
  97 #include <linux/unistd.h>
  98 #include <linux/wait.h>
  99 #include <linux/workqueue.h>
 100 #include <net/sock.h>
 101
 102 #include "af_vsock.h"
 103 #include "vsock_version.h"
 104
 105 static int __vsock_bind(struct sock *sk, struct sockaddr_vm *addr);
 106 static void vsock_sk_destruct(struct sock *sk);
 107 static int vsock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
 108
 109 /* Protocol family. */
 110 static struct proto vsock_proto = {
 111         .name = "AF_VSOCK",
 112         .owner = THIS_MODULE,
 113         .obj_size = sizeof(struct vsock_sock),
 114 };
 115
 116 /* The default peer timeout indicates how long we will wait for a peer response
 117  * to a control message.
 118  */
 119 #define VSOCK_DEFAULT_CONNECT_TIMEOUT (2 * HZ)
 120
 121 #define SS_LISTEN 255
 122
 123 static const struct vsock_transport *transport;
 124 static DEFINE_MUTEX(vsock_register_mutex);
 125
 126 /**** EXPORTS ****/
 127
 128 /* Get the ID of the local context.  This is transport dependent. */
 129
 130 int vm_sockets_get_local_cid(void)
 131 {
 132         return transport->get_local_cid();
 133 }
 134 EXPORT_SYMBOL_GPL(vm_sockets_get_local_cid);
 135
 136 /**** UTILS ****/
 137
 138 /* Each bound VSocket is stored in the bind hash table and each connected
 139  * VSocket is stored in the connected hash table.
 140  *
 141  * Unbound sockets are all put on the same list attached to the end of the hash
 142  * table (vsock_unbound_sockets).  Bound sockets are added to the hash table in
 143  * the bucket that their local address hashes to (vsock_bound_sockets(addr)
 144  * represents the list that addr hashes to).
 145  *
 146  * Specifically, we initialize the vsock_bind_table array to a size of
 147  * VSOCK_HASH_SIZE + 1 so that vsock_bind_table[0] through
 148  * vsock_bind_table[VSOCK_HASH_SIZE - 1] are for bound sockets and
 149  * vsock_bind_table[VSOCK_HASH_SIZE] is for unbound sockets.  The hash function
 150  * mods with VSOCK_HASH_SIZE - 1 to ensure this.
 151  */
 152 #define VSOCK_HASH_SIZE         251
 153 #define MAX_PORT_RETRIES        24
 154
 155 #define VSOCK_HASH(addr)        ((addr)->svm_port % (VSOCK_HASH_SIZE - 1))
 156 #define vsock_bound_sockets(addr) (&vsock_bind_table[VSOCK_HASH(addr)])
 157 #define vsock_unbound_sockets     (&vsock_bind_table[VSOCK_HASH_SIZE])
 158
 159 /* XXX This can probably be implemented in a better way. */
 160 #define VSOCK_CONN_HASH(src, dst)                               \
 161         (((src)->svm_cid ^ (dst)->svm_port) % (VSOCK_HASH_SIZE - 1))
 162 #define vsock_connected_sockets(src, dst)               \
 163         (&vsock_connected_table[VSOCK_CONN_HASH(src, dst)])
 164 #define vsock_connected_sockets_vsk(vsk)                                \
 165         vsock_connected_sockets(&(vsk)->remote_addr, &(vsk)->local_addr)
 166
 167 static struct list_head vsock_bind_table[VSOCK_HASH_SIZE + 1];
 168 static struct list_head vsock_connected_table[VSOCK_HASH_SIZE];
 169 static DEFINE_SPINLOCK(vsock_table_lock);
 170
 171 static __init void vsock_init_tables(void)
 172 {
 173         int i;
 174
 175         for (i = 0; i < ARRAY_SIZE(vsock_bind_table); i++)
 176                 INIT_LIST_HEAD(&vsock_bind_table[i]);
 177
 178         for (i = 0; i < ARRAY_SIZE(vsock_connected_table); i++)
 179                 INIT_LIST_HEAD(&vsock_connected_table[i]);
 180 }
 181
 182 static void __vsock_insert_bound(struct list_head *list,
 183                                  struct vsock_sock *vsk)
 184 {
 185         sock_hold(&vsk->sk);
 186         list_add(&vsk->bound_table, list);
 187 }
 188
 189 static void __vsock_insert_connected(struct list_head *list,
 190                                      struct vsock_sock *vsk)
 191 {
 192         sock_hold(&vsk->sk);
 193         list_add(&vsk->connected_table, list);
 194 }
 195
 196 static void __vsock_remove_bound(struct vsock_sock *vsk)
 197 {
 198         list_del_init(&vsk->bound_table);
 199         sock_put(&vsk->sk);
 200 }
 201
 202 static void __vsock_remove_connected(struct vsock_sock *vsk)
 203 {
 204         list_del_init(&vsk->connected_table);
 205         sock_put(&vsk->sk);
 206 }
 207
 208 static struct sock *__vsock_find_bound_socket(struct sockaddr_vm *addr)
 209 {
 210         struct vsock_sock *vsk;
 211
 212         list_for_each_entry(vsk, vsock_bound_sockets(addr), bound_table)
 213                 if (vsock_addr_equals_addr_any(addr, &vsk->local_addr))
 214                         return sk_vsock(vsk);
 215
 216         return NULL;
 217 }
 218
 219 static struct sock *__vsock_find_connected_socket(struct sockaddr_vm *src,
 220                                                   struct sockaddr_vm *dst)
 221 {
 222         struct vsock_sock *vsk;
 223
 224         list_for_each_entry(vsk, vsock_connected_sockets(src, dst),
 225                             connected_table) {
 226                 if (vsock_addr_equals_addr(src, &vsk->remote_addr)
 227                     && vsock_addr_equals_addr(dst, &vsk->local_addr)) {
 228                         return sk_vsock(vsk);
 229                 }
 230         }
 231
 232         return NULL;
 233 }
 234
 235 static bool __vsock_in_bound_table(struct vsock_sock *vsk)
 236 {
 237         return !list_empty(&vsk->bound_table);
 238 }
 239
 240 static bool __vsock_in_connected_table(struct vsock_sock *vsk)
 241 {
 242         return !list_empty(&vsk->connected_table);
 243 }
 244
 245 static void vsock_insert_unbound(struct vsock_sock *vsk)
 246 {
 247         spin_lock_bh(&vsock_table_lock);
 248         __vsock_insert_bound(vsock_unbound_sockets, vsk);
 249         spin_unlock_bh(&vsock_table_lock);
 250 }
 251
 252 void vsock_insert_connected(struct vsock_sock *vsk)
 253 {
 254         struct list_head *list = vsock_connected_sockets(
 255                 &vsk->remote_addr, &vsk->local_addr);
 256
 257         spin_lock_bh(&vsock_table_lock);
 258         __vsock_insert_connected(list, vsk);
 259         spin_unlock_bh(&vsock_table_lock);
 260 }
 261 EXPORT_SYMBOL_GPL(vsock_insert_connected);
 262
 263 void vsock_remove_bound(struct vsock_sock *vsk)
 264 {
 265         spin_lock_bh(&vsock_table_lock);
 266         __vsock_remove_bound(vsk);
 267         spin_unlock_bh(&vsock_table_lock);
 268 }
 269 EXPORT_SYMBOL_GPL(vsock_remove_bound);
 270
 271 void vsock_remove_connected(struct vsock_sock *vsk)
 272 {
 273         spin_lock_bh(&vsock_table_lock);
 274         __vsock_remove_connected(vsk);
 275         spin_unlock_bh(&vsock_table_lock);
 276 }
 277 EXPORT_SYMBOL_GPL(vsock_remove_connected);
 278
 279 struct sock *vsock_find_bound_socket(struct sockaddr_vm *addr)
 280 {
 281         struct sock *sk;
 282
 283         spin_lock_bh(&vsock_table_lock);
 284         sk = __vsock_find_bound_socket(addr);
 285         if (sk)
 286                 sock_hold(sk);
 287
 288         spin_unlock_bh(&vsock_table_lock);
 289
 290         return sk;
 291 }
 292 EXPORT_SYMBOL_GPL(vsock_find_bound_socket);
 293
 294 struct sock *vsock_find_connected_socket(struct sockaddr_vm *src,
 295                                          struct sockaddr_vm *dst)
 296 {
 297         struct sock *sk;
 298
 299         spin_lock_bh(&vsock_table_lock);
 300         sk = __vsock_find_connected_socket(src, dst);
 301         if (sk)
 302                 sock_hold(sk);
 303
 304         spin_unlock_bh(&vsock_table_lock);
 305
 306         return sk;
 307 }
 308 EXPORT_SYMBOL_GPL(vsock_find_connected_socket);
 309
 310 static bool vsock_in_bound_table(struct vsock_sock *vsk)
 311 {
 312         bool ret;
 313
 314         spin_lock_bh(&vsock_table_lock);
 315         ret = __vsock_in_bound_table(vsk);
 316         spin_unlock_bh(&vsock_table_lock);
 317
 318         return ret;
 319 }
 320
 321 static bool vsock_in_connected_table(struct vsock_sock *vsk)
 322 {
 323         bool ret;
 324
 325         spin_lock_bh(&vsock_table_lock);
 326         ret = __vsock_in_connected_table(vsk);
 327         spin_unlock_bh(&vsock_table_lock);
 328
 329         return ret;
 330 }
 331
 332 void vsock_for_each_connected_socket(void (*fn)(struct sock *sk))
 333 {
 334         int i;
 335
 336         spin_lock_bh(&vsock_table_lock);
 337
 338         for (i = 0; i < ARRAY_SIZE(vsock_connected_table); i++) {
 339                 struct vsock_sock *vsk;
 340                 list_for_each_entry(vsk, &vsock_connected_table[i],
 341                                     connected_table);
 342                         fn(sk_vsock(vsk));
 343         }
 344
 345         spin_unlock_bh(&vsock_table_lock);
 346 }
 347 EXPORT_SYMBOL_GPL(vsock_for_each_connected_socket);
 348
 349 void vsock_add_pending(struct sock *listener, struct sock *pending)
 350 {
 351         struct vsock_sock *vlistener;
 352         struct vsock_sock *vpending;
 353
 354         vlistener = vsock_sk(listener);
 355         vpending = vsock_sk(pending);
 356
 357         sock_hold(pending);
 358         sock_hold(listener);
 359         list_add_tail(&vpending->pending_links, &vlistener->pending_links);
 360 }
 361 EXPORT_SYMBOL_GPL(vsock_add_pending);
 362
 363 void vsock_remove_pending(struct sock *listener, struct sock *pending)
 364 {
 365         struct vsock_sock *vpending = vsock_sk(pending);
 366
 367         list_del_init(&vpending->pending_links);
 368         sock_put(listener);
 369         sock_put(pending);
 370 }
 371 EXPORT_SYMBOL_GPL(vsock_remove_pending);
 372
 373 void vsock_enqueue_accept(struct sock *listener, struct sock *connected)
 374 {
 375         struct vsock_sock *vlistener;
 376         struct vsock_sock *vconnected;
 377
 378         vlistener = vsock_sk(listener);
 379         vconnected = vsock_sk(connected);
 380
 381         sock_hold(connected);
 382         sock_hold(listener);
 383         list_add_tail(&vconnected->accept_queue, &vlistener->accept_queue);
 384 }
 385 EXPORT_SYMBOL_GPL(vsock_enqueue_accept);
 386
 387 static struct sock *vsock_dequeue_accept(struct sock *listener)
 388 {
 389         struct vsock_sock *vlistener;
 390         struct vsock_sock *vconnected;
 391
 392         vlistener = vsock_sk(listener);
 393
 394         if (list_empty(&vlistener->accept_queue))
 395                 return NULL;
 396
 397         vconnected = list_entry(vlistener->accept_queue.next,
 398                                 struct vsock_sock, accept_queue);
 399
 400         list_del_init(&vconnected->accept_queue);
 401         sock_put(listener);
 402         /* The caller will need a reference on the connected socket so we let
 403          * it call sock_put().
 404          */
 405
 406         return sk_vsock(vconnected);
 407 }
 408
 409 static bool vsock_is_accept_queue_empty(struct sock *sk)
 410 {
 411         struct vsock_sock *vsk = vsock_sk(sk);
 412         return list_empty(&vsk->accept_queue);
 413 }
 414
 415 static bool vsock_is_pending(struct sock *sk)
 416 {
 417         struct vsock_sock *vsk = vsock_sk(sk);
 418         return !list_empty(&vsk->pending_links);
 419 }
 420
 421 static int vsock_send_shutdown(struct sock *sk, int mode)
 422 {
 423         return transport->shutdown(vsock_sk(sk), mode);
 424 }
 425
 426 void vsock_pending_work(struct work_struct *work)
 427 {
 428         struct sock *sk;
 429         struct sock *listener;
 430         struct vsock_sock *vsk;
 431         bool cleanup;
 432
 433         vsk = container_of(work, struct vsock_sock, dwork.work);
 434         sk = sk_vsock(vsk);
 435         listener = vsk->listener;
 436         cleanup = true;
 437
 438         lock_sock(listener);
 439         lock_sock(sk);
 440
 441         if (vsock_is_pending(sk)) {
 442                 vsock_remove_pending(listener, sk);
 443         } else if (!vsk->rejected) {
 444                 /* We are not on the pending list and accept() did not reject
 445                  * us, so we must have been accepted by our user process.  We
 446                  * just need to drop our references to the sockets and be on
 447                  * our way.
 448                  */
 449                 cleanup = false;
 450                 goto out;
 451         }
 452
 453         listener->sk_ack_backlog--;
 454
 455         /* We need to remove ourself from the global connected sockets list so
 456          * incoming packets can't find this socket, and to reduce the reference
 457          * count.
 458          */
 459         if (vsock_in_connected_table(vsk))
 460                 vsock_remove_connected(vsk);
 461
 462         sk->sk_state = SS_FREE;
 463
 464 out:
 465         release_sock(sk);
 466         release_sock(listener);
 467         if (cleanup)
 468                 sock_put(sk);
 469
 470         sock_put(sk);
 471         sock_put(listener);
 472 }
 473 EXPORT_SYMBOL_GPL(vsock_pending_work);
 474
 475 /**** SOCKET OPERATIONS ****/
 476
 477 static int __vsock_bind_stream(struct vsock_sock *vsk,
 478                                struct sockaddr_vm *addr)
 479 {
 480         static u32 port = LAST_RESERVED_PORT + 1;
 481         struct sockaddr_vm new_addr;
 482
 483         vsock_addr_init(&new_addr, addr->svm_cid, addr->svm_port);
 484
 485         if (addr->svm_port == VMADDR_PORT_ANY) {
 486                 bool found = false;
 487                 unsigned int i;
 488
 489                 for (i = 0; i < MAX_PORT_RETRIES; i++) {
 490                         if (port <= LAST_RESERVED_PORT)
 491                                 port = LAST_RESERVED_PORT + 1;
 492
 493                         new_addr.svm_port = port++;
 494
 495                         if (!__vsock_find_bound_socket(&new_addr)) {
 496                                 found = true;
 497                                 break;
 498                         }
 499                 }
 500
 501                 if (!found)
 502                         return -EADDRNOTAVAIL;
 503         } else {
 504                 /* If port is in reserved range, ensure caller
 505                  * has necessary privileges.
 506                  */
 507                 if (addr->svm_port <= LAST_RESERVED_PORT &&
 508                     !capable(CAP_NET_BIND_SERVICE)) {
 509                         return -EACCES;
 510                 }
 511
 512                 if (__vsock_find_bound_socket(&new_addr))
 513                         return -EADDRINUSE;
 514         }
 515
 516         vsock_addr_init(&vsk->local_addr, new_addr.svm_cid, new_addr.svm_port);
 517
 518         /* Remove stream sockets from the unbound list and add them to the hash
 519          * table for easy lookup by its address.  The unbound list is simply an
 520          * extra entry at the end of the hash table, a trick used by AF_UNIX.
 521          */
 522         __vsock_remove_bound(vsk);
 523         __vsock_insert_bound(vsock_bound_sockets(&vsk->local_addr), vsk);
 524
 525         return 0;
 526 }
 527
 528 static int __vsock_bind_dgram(struct vsock_sock *vsk,
 529                               struct sockaddr_vm *addr)
 530 {
 531         return transport->dgram_bind(vsk, addr);
 532 }
 533
 534 static int __vsock_bind(struct sock *sk, struct sockaddr_vm *addr)
 535 {
 536         struct vsock_sock *vsk = vsock_sk(sk);
 537         u32 cid;
 538         int retval;
 539
 540         /* First ensure this socket isn't already bound. */
 541         if (vsock_addr_bound(&vsk->local_addr))
 542                 return -EINVAL;
 543
 544         /* Now bind to the provided address or select appropriate values if
 545          * none are provided (VMADDR_CID_ANY and VMADDR_PORT_ANY).  Note that
 546          * like AF_INET prevents binding to a non-local IP address (in most
 547          * cases), we only allow binding to the local CID.
 548          */
 549         cid = transport->get_local_cid();
 550         if (addr->svm_cid != cid && addr->svm_cid != VMADDR_CID_ANY)
 551                 return -EADDRNOTAVAIL;
 552
 553         switch (sk->sk_socket->type) {
 554         case SOCK_STREAM:
 555                 spin_lock_bh(&vsock_table_lock);
 556                 retval = __vsock_bind_stream(vsk, addr);
 557                 spin_unlock_bh(&vsock_table_lock);
 558                 break;
 559
 560         case SOCK_DGRAM:
 561                 retval = __vsock_bind_dgram(vsk, addr);
 562                 break;
 563
 564         default:
 565                 retval = -EINVAL;
 566                 break;
 567         }
 568
 569         return retval;
 570 }
 571
 572 struct sock *__vsock_create(struct net *net,
 573                             struct socket *sock,
 574                             struct sock *parent,
 575                             gfp_t priority,
 576                             unsigned short type)
 577 {
 578         struct sock *sk;
 579         struct vsock_sock *psk;
 580         struct vsock_sock *vsk;
 581
 582         sk = sk_alloc(net, AF_VSOCK, priority, &vsock_proto);
 583         if (!sk)
 584                 return NULL;
 585
 586         sock_init_data(sock, sk);
 587
 588         /* sk->sk_type is normally set in sock_init_data, but only if sock is
 589          * non-NULL. We make sure that our sockets always have a type by
 590          * setting it here if needed.
 591          */
 592         if (!sock)
 593                 sk->sk_type = type;
 594
 595         vsk = vsock_sk(sk);
 596         vsock_addr_init(&vsk->local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
 597         vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
 598
 599         sk->sk_destruct = vsock_sk_destruct;
 600         sk->sk_backlog_rcv = vsock_queue_rcv_skb;
 601         sk->sk_state = 0;
 602         sock_reset_flag(sk, SOCK_DONE);
 603
 604         INIT_LIST_HEAD(&vsk->bound_table);
 605         INIT_LIST_HEAD(&vsk->connected_table);
 606         vsk->listener = NULL;
 607         INIT_LIST_HEAD(&vsk->pending_links);
 608         INIT_LIST_HEAD(&vsk->accept_queue);
 609         vsk->rejected = false;
 610         vsk->sent_request = false;
 611         vsk->ignore_connecting_rst = false;
 612         vsk->peer_shutdown = 0;
 613
 614         psk = parent ? vsock_sk(parent) : NULL;
 615         if (parent) {
 616                 vsk->trusted = psk->trusted;
 617                 vsk->owner = get_cred(psk->owner);
 618                 vsk->connect_timeout = psk->connect_timeout;
 619         } else {
 620                 vsk->trusted = capable(CAP_NET_ADMIN);
 621                 vsk->owner = get_current_cred();
 622                 vsk->connect_timeout = VSOCK_DEFAULT_CONNECT_TIMEOUT;
 623         }
 624
 625         if (transport->init(vsk, psk) < 0) {
 626                 sk_free(sk);
 627                 return NULL;
 628         }
 629
 630         if (sock)
 631                 vsock_insert_unbound(vsk);
 632
 633         return sk;
 634 }
 635 EXPORT_SYMBOL_GPL(__vsock_create);
 636
 637 static void __vsock_release(struct sock *sk)
 638 {
 639         if (sk) {
 640                 struct sk_buff *skb;
 641                 struct sock *pending;
 642                 struct vsock_sock *vsk;
 643
 644                 vsk = vsock_sk(sk);
 645                 pending = NULL; /* Compiler warning. */
 646
 647                 if (vsock_in_bound_table(vsk))
 648                         vsock_remove_bound(vsk);
 649
 650                 if (vsock_in_connected_table(vsk))
 651                         vsock_remove_connected(vsk);
 652
 653                 transport->release(vsk);
 654
 655                 lock_sock(sk);
 656                 sock_orphan(sk);
 657                 sk->sk_shutdown = SHUTDOWN_MASK;
 658
 659                 while ((skb = skb_dequeue(&sk->sk_receive_queue)))
 660                         kfree_skb(skb);
 661
 662                 /* Clean up any sockets that never were accepted. */
 663                 while ((pending = vsock_dequeue_accept(sk)) != NULL) {
 664                         __vsock_release(pending);
 665                         sock_put(pending);
 666                 }
 667
 668                 release_sock(sk);
 669                 sock_put(sk);
 670         }
 671 }
 672
 673 static void vsock_sk_destruct(struct sock *sk)
 674 {
 675         struct vsock_sock *vsk = vsock_sk(sk);
 676
 677         transport->destruct(vsk);
 678
 679         /* When clearing these addresses, there's no need to set the family and
 680          * possibly register the address family with the kernel.
 681          */
 682         vsock_addr_init(&vsk->local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
 683         vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
 684
 685         put_cred(vsk->owner);
 686 }
 687
 688 static int vsock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 689 {
 690         int err;
 691
 692         err = sock_queue_rcv_skb(sk, skb);
 693         if (err)
 694                 kfree_skb(skb);
 695
 696         return err;
 697 }
 698
 699 s64 vsock_stream_has_data(struct vsock_sock *vsk)
 700 {
 701         return transport->stream_has_data(vsk);
 702 }
 703 EXPORT_SYMBOL_GPL(vsock_stream_has_data);
 704
 705 s64 vsock_stream_has_space(struct vsock_sock *vsk)
 706 {
 707         return transport->stream_has_space(vsk);
 708 }
 709 EXPORT_SYMBOL_GPL(vsock_stream_has_space);
 710
 711 static int vsock_release(struct socket *sock)
 712 {
 713         __vsock_release(sock->sk);
 714         sock->sk = NULL;
 715         sock->state = SS_FREE;
 716
 717         return 0;
 718 }
 719
 720 static int
 721 vsock_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
 722 {
 723         int err;
 724         struct sock *sk;
 725         struct sockaddr_vm *vm_addr;
 726
 727         sk = sock->sk;
 728
 729         if (vsock_addr_cast(addr, addr_len, &vm_addr) != 0)
 730                 return -EINVAL;
 731
 732         lock_sock(sk);
 733         err = __vsock_bind(sk, vm_addr);
 734         release_sock(sk);
 735
 736         return err;
 737 }
 738
 739 static int vsock_getname(struct socket *sock,
 740                          struct sockaddr *addr, int *addr_len, int peer)
 741 {
 742         int err;
 743         struct sock *sk;
 744         struct vsock_sock *vsk;
 745         struct sockaddr_vm *vm_addr;
 746
 747         sk = sock->sk;
 748         vsk = vsock_sk(sk);
 749         err = 0;
 750
 751         lock_sock(sk);
 752
 753         if (peer) {
 754                 if (sock->state != SS_CONNECTED) {
 755                         err = -ENOTCONN;
 756                         goto out;
 757                 }
 758                 vm_addr = &vsk->remote_addr;
 759         } else {
 760                 vm_addr = &vsk->local_addr;
 761         }
 762
 763         if (!vm_addr) {
 764                 err = -EINVAL;
 765                 goto out;
 766         }
 767
 768         /* sys_getsockname() and sys_getpeername() pass us a
 769          * MAX_SOCK_ADDR-sized buffer and don't set addr_len.  Unfortunately
 770          * that macro is defined in socket.c instead of .h, so we hardcode its
 771          * value here.
 772          */
 773         BUILD_BUG_ON(sizeof(*vm_addr) > 128);
 774         memcpy(addr, vm_addr, sizeof(*vm_addr));
 775         *addr_len = sizeof(*vm_addr);
 776
 777 out:
 778         release_sock(sk);
 779         return err;
 780 }
 781
 782 static int vsock_shutdown(struct socket *sock, int mode)
 783 {
 784         int err;
 785         struct sock *sk;
 786
 787         /* User level uses SHUT_RD (0) and SHUT_WR (1), but the kernel uses
 788          * RCV_SHUTDOWN (1) and SEND_SHUTDOWN (2), so we must increment mode
 789          * here like the other address families do.  Note also that the
 790          * increment makes SHUT_RDWR (2) into RCV_SHUTDOWN | SEND_SHUTDOWN (3),
 791          * which is what we want.
 792          */
 793         mode++;
 794
 795         if ((mode & ~SHUTDOWN_MASK) || !mode)
 796                 return -EINVAL;
 797
 798         /* If this is a STREAM socket and it is not connected then bail out
 799          * immediately.  If it is a DGRAM socket then we must first kick the
 800          * socket so that it wakes up from any sleeping calls, for example
 801          * recv(), and then afterwards return the error.
 802          */
 803
 804         sk = sock->sk;
 805         if (sock->state == SS_UNCONNECTED) {
 806                 err = -ENOTCONN;
 807                 if (sk->sk_type == SOCK_STREAM)
 808                         return err;
 809         } else {
 810                 sock->state = SS_DISCONNECTING;
 811                 err = 0;
 812         }
 813
 814         /* Receive and send shutdowns are treated alike. */
 815         mode = mode & (RCV_SHUTDOWN | SEND_SHUTDOWN);
 816         if (mode) {
 817                 lock_sock(sk);
 818                 sk->sk_shutdown |= mode;
 819                 sk->sk_state_change(sk);
 820                 release_sock(sk);
 821
 822                 if (sk->sk_type == SOCK_STREAM) {
 823                         sock_reset_flag(sk, SOCK_DONE);
 824                         vsock_send_shutdown(sk, mode);
 825                 }
 826         }
 827
 828         return err;
 829 }
 830
 831 static unsigned int vsock_poll(struct file *file, struct socket *sock,
 832                                poll_table *wait)
 833 {
 834         struct sock *sk;
 835         unsigned int mask;
 836         struct vsock_sock *vsk;
 837
 838         sk = sock->sk;
 839         vsk = vsock_sk(sk);
 840
 841         poll_wait(file, sk_sleep(sk), wait);
 842         mask = 0;
 843
 844         if (sk->sk_err)
 845                 /* Signify that there has been an error on this socket. */
 846                 mask |= POLLERR;
 847
 848         /* INET sockets treat local write shutdown and peer write shutdown as a
 849          * case of POLLHUP set.
 850          */
 851         if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
 852             ((sk->sk_shutdown & SEND_SHUTDOWN) &&
 853              (vsk->peer_shutdown & SEND_SHUTDOWN))) {
 854                 mask |= POLLHUP;
 855         }
 856
 857         if (sk->sk_shutdown & RCV_SHUTDOWN ||
 858             vsk->peer_shutdown & SEND_SHUTDOWN) {
 859                 mask |= POLLRDHUP;
 860         }
 861
 862         if (sock->type == SOCK_DGRAM) {
 863                 /* For datagram sockets we can read if there is something in
 864                  * the queue and write as long as the socket isn't shutdown for
 865                  * sending.
 866                  */
 867                 if (!skb_queue_empty(&sk->sk_receive_queue) ||
 868                     (sk->sk_shutdown & RCV_SHUTDOWN)) {
 869                         mask |= POLLIN | POLLRDNORM;
 870                 }
 871
 872                 if (!(sk->sk_shutdown & SEND_SHUTDOWN))
 873                         mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
 874
 875         } else if (sock->type == SOCK_STREAM) {
 876                 lock_sock(sk);
 877
 878                 /* Listening sockets that have connections in their accept
 879                  * queue can be read.
 880                  */
 881                 if (sk->sk_state == SS_LISTEN
 882                     && !vsock_is_accept_queue_empty(sk))
 883                         mask |= POLLIN | POLLRDNORM;
 884
 885                 /* If there is something in the queue then we can read. */
 886                 if (transport->stream_is_active(vsk) &&
 887                     !(sk->sk_shutdown & RCV_SHUTDOWN)) {
 888                         bool data_ready_now = false;
 889                         int ret = transport->notify_poll_in(
 890                                         vsk, 1, &data_ready_now);
 891                         if (ret < 0) {
 892                                 mask |= POLLERR;
 893                         } else {
 894                                 if (data_ready_now)
 895                                         mask |= POLLIN | POLLRDNORM;
 896
 897                         }
 898                 }
 899
 900                 /* Sockets whose connections have been closed, reset, or
 901                  * terminated should also be considered read, and we check the
 902                  * shutdown flag for that.
 903                  */
 904                 if (sk->sk_shutdown & RCV_SHUTDOWN ||
 905                     vsk->peer_shutdown & SEND_SHUTDOWN) {
 906                         mask |= POLLIN | POLLRDNORM;
 907                 }
 908
 909                 /* Connected sockets that can produce data can be written. */
 910                 if (sk->sk_state == SS_CONNECTED) {
 911                         if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
 912                                 bool space_avail_now = false;
 913                                 int ret = transport->notify_poll_out(
 914                                                 vsk, 1, &space_avail_now);
 915                                 if (ret < 0) {
 916                                         mask |= POLLERR;
 917                                 } else {
 918                                         if (space_avail_now)
 919                                                 /* Remove POLLWRBAND since INET
 920                                                  * sockets are not setting it.
 921                                                  */
 922                                                 mask |= POLLOUT | POLLWRNORM;
 923
 924                                 }
 925                         }
 926                 }
 927
 928                 /* Simulate INET socket poll behaviors, which sets
 929                  * POLLOUT|POLLWRNORM when peer is closed and nothing to read,
 930                  * but local send is not shutdown.
 931                  */
 932                 if (sk->sk_state == SS_UNCONNECTED) {
 933                         if (!(sk->sk_shutdown & SEND_SHUTDOWN))
 934                                 mask |= POLLOUT | POLLWRNORM;
 935
 936                 }
 937
 938                 release_sock(sk);
 939         }
 940
 941         return mask;
 942 }
 943
 944 static int vsock_dgram_sendmsg(struct kiocb *kiocb, struct socket *sock,
 945                                struct msghdr *msg, size_t len)
 946 {
 947         int err;
 948         struct sock *sk;
 949         struct vsock_sock *vsk;
 950         struct sockaddr_vm *remote_addr;
 951
 952         if (msg->msg_flags & MSG_OOB)
 953                 return -EOPNOTSUPP;
 954
 955         /* For now, MSG_DONTWAIT is always assumed... */
 956         err = 0;
 957         sk = sock->sk;
 958         vsk = vsock_sk(sk);
 959
 960         lock_sock(sk);
 961
 962         if (!vsock_addr_bound(&vsk->local_addr)) {
 963                 struct sockaddr_vm local_addr;
 964
 965                 vsock_addr_init(&local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
 966                 err = __vsock_bind(sk, &local_addr);
 967                 if (err != 0)
 968                         goto out;
 969
 970         }
 971
 972         /* If the provided message contains an address, use that.  Otherwise
 973          * fall back on the socket's remote handle (if it has been connected).
 974          */
 975         if (msg->msg_name &&
 976             vsock_addr_cast(msg->msg_name, msg->msg_namelen,
 977                             &remote_addr) == 0) {
 978                 /* Ensure this address is of the right type and is a valid
 979                  * destination.
 980                  */
 981
 982                 if (remote_addr->svm_cid == VMADDR_CID_ANY)
 983                         remote_addr->svm_cid = transport->get_local_cid();
 984
 985                 if (!vsock_addr_bound(remote_addr)) {
 986                         err = -EINVAL;
 987                         goto out;
 988                 }
 989         } else if (sock->state == SS_CONNECTED) {
 990                 remote_addr = &vsk->remote_addr;
 991
 992                 if (remote_addr->svm_cid == VMADDR_CID_ANY)
 993                         remote_addr->svm_cid = transport->get_local_cid();
 994
 995                 /* XXX Should connect() or this function ensure remote_addr is
 996                  * bound?
 997                  */
 998                 if (!vsock_addr_bound(&vsk->remote_addr)) {
 999                         err = -EINVAL;
1000                         goto out;
1001                 }
1002         } else {
1003                 err = -EINVAL;
1004                 goto out;
1005         }
1006
1007         if (!transport->dgram_allow(remote_addr->svm_cid,
1008                                     remote_addr->svm_port)) {
1009                 err = -EINVAL;
1010                 goto out;
1011         }
1012
1013         err = transport->dgram_enqueue(vsk, remote_addr, msg->msg_iov, len);
1014
1015 out:
1016         release_sock(sk);
1017         return err;
1018 }
1019
1020 static int vsock_dgram_connect(struct socket *sock,
1021                                struct sockaddr *addr, int addr_len, int flags)
1022 {
1023         int err;
1024         struct sock *sk;
1025         struct vsock_sock *vsk;
1026         struct sockaddr_vm *remote_addr;
1027
1028         sk = sock->sk;
1029         vsk = vsock_sk(sk);
1030
1031         err = vsock_addr_cast(addr, addr_len, &remote_addr);
1032         if (err == -EAFNOSUPPORT && remote_addr->svm_family == AF_UNSPEC) {
1033                 lock_sock(sk);
1034                 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY,
1035                                 VMADDR_PORT_ANY);
1036                 sock->state = SS_UNCONNECTED;
1037                 release_sock(sk);
1038                 return 0;
1039         } else if (err != 0)
1040                 return -EINVAL;
1041
1042         lock_sock(sk);
1043
1044         if (!vsock_addr_bound(&vsk->local_addr)) {
1045                 struct sockaddr_vm local_addr;
1046
1047                 vsock_addr_init(&local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
1048                 err = __vsock_bind(sk, &local_addr);
1049                 if (err != 0)
1050                         goto out;
1051
1052         }
1053
1054         if (!transport->dgram_allow(remote_addr->svm_cid,
1055                                     remote_addr->svm_port)) {
1056                 err = -EINVAL;
1057                 goto out;
1058         }
1059
1060         memcpy(&vsk->remote_addr, remote_addr, sizeof(vsk->remote_addr));
1061         sock->state = SS_CONNECTED;
1062
1063 out:
1064         release_sock(sk);
1065         return err;
1066 }
1067
1068 static int vsock_dgram_recvmsg(struct kiocb *kiocb, struct socket *sock,
1069                                struct msghdr *msg, size_t len, int flags)
1070 {
1071         return transport->dgram_dequeue(kiocb, vsock_sk(sock->sk), msg, len,
1072                                         flags);
1073 }
1074
1075 static const struct proto_ops vsock_dgram_ops = {
1076         .family = PF_VSOCK,
1077         .owner = THIS_MODULE,
1078         .release = vsock_release,
1079         .bind = vsock_bind,
1080         .connect = vsock_dgram_connect,
1081         .socketpair = sock_no_socketpair,
1082         .accept = sock_no_accept,
1083         .getname = vsock_getname,
1084         .poll = vsock_poll,
1085         .ioctl = sock_no_ioctl,
1086         .listen = sock_no_listen,
1087         .shutdown = vsock_shutdown,
1088         .setsockopt = sock_no_setsockopt,
1089         .getsockopt = sock_no_getsockopt,
1090         .sendmsg = vsock_dgram_sendmsg,
1091         .recvmsg = vsock_dgram_recvmsg,
1092         .mmap = sock_no_mmap,
1093         .sendpage = sock_no_sendpage,
1094 };
1095
1096 static void vsock_connect_timeout(struct work_struct *work)
1097 {
1098         struct sock *sk;
1099         struct vsock_sock *vsk;
1100
1101         vsk = container_of(work, struct vsock_sock, dwork.work);
1102         sk = sk_vsock(vsk);
1103
1104         lock_sock(sk);
1105         if (sk->sk_state == SS_CONNECTING &&
1106             (sk->sk_shutdown != SHUTDOWN_MASK)) {
1107                 sk->sk_state = SS_UNCONNECTED;
1108                 sk->sk_err = ETIMEDOUT;
1109                 sk->sk_error_report(sk);
1110         }
1111         release_sock(sk);
1112
1113         sock_put(sk);
1114 }
1115
1116 static int vsock_stream_connect(struct socket *sock, struct sockaddr *addr,
1117                                 int addr_len, int flags)
1118 {
1119         int err;
1120         struct sock *sk;
1121         struct vsock_sock *vsk;
1122         struct sockaddr_vm *remote_addr;
1123         long timeout;
1124         DEFINE_WAIT(wait);
1125
1126         err = 0;
1127         sk = sock->sk;
1128         vsk = vsock_sk(sk);
1129
1130         lock_sock(sk);
1131
1132         /* XXX AF_UNSPEC should make us disconnect like AF_INET. */
1133         switch (sock->state) {
1134         case SS_CONNECTED:
1135                 err = -EISCONN;
1136                 goto out;
1137         case SS_DISCONNECTING:
1138                 err = -EINVAL;
1139                 goto out;
1140         case SS_CONNECTING:
1141                 /* This continues on so we can move sock into the SS_CONNECTED
1142                  * state once the connection has completed (at which point err
1143                  * will be set to zero also).  Otherwise, we will either wait
1144                  * for the connection or return -EALREADY should this be a
1145                  * non-blocking call.
1146                  */
1147                 err = -EALREADY;
1148                 break;
1149         default:
1150                 if ((sk->sk_state == SS_LISTEN) ||
1151                     vsock_addr_cast(addr, addr_len, &remote_addr) != 0) {
1152                         err = -EINVAL;
1153                         goto out;
1154                 }
1155
1156                 /* The hypervisor and well-known contexts do not have socket
1157                  * endpoints.
1158                  */
1159                 if (!transport->stream_allow(remote_addr->svm_cid,
1160                                              remote_addr->svm_port)) {
1161                         err = -ENETUNREACH;
1162                         goto out;
1163                 }
1164
1165                 /* Set the remote address that we are connecting to. */
1166                 memcpy(&vsk->remote_addr, remote_addr,
1167                        sizeof(vsk->remote_addr));
1168
1169                 /* Autobind this socket to the local address if necessary. */
1170                 if (!vsock_addr_bound(&vsk->local_addr)) {
1171                         struct sockaddr_vm local_addr;
1172
1173                         vsock_addr_init(&local_addr, VMADDR_CID_ANY,
1174                                         VMADDR_PORT_ANY);
1175                         err = __vsock_bind(sk, &local_addr);
1176                         if (err != 0)
1177                                 goto out;
1178
1179                 }
1180
1181                 sk->sk_state = SS_CONNECTING;
1182
1183                 err = transport->connect(vsk);
1184                 if (err < 0)
1185                         goto out;
1186
1187                 /* Mark sock as connecting and set the error code to in
1188                  * progress in case this is a non-blocking connect.
1189                  */
1190                 sock->state = SS_CONNECTING;
1191                 err = -EINPROGRESS;
1192         }
1193
1194         /* The receive path will handle all communication until we are able to
1195          * enter the connected state.  Here we wait for the connection to be
1196          * completed or a notification of an error.
1197          */
1198         timeout = vsk->connect_timeout;
1199         prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1200
1201         while (sk->sk_state != SS_CONNECTED && sk->sk_err == 0) {
1202                 if (flags & O_NONBLOCK) {
1203                         /* If we're not going to block, we schedule a timeout
1204                          * function to generate a timeout on the connection
1205                          * attempt, in case the peer doesn't respond in a
1206                          * timely manner. We hold on to the socket until the
1207                          * timeout fires.
1208                          */
1209                         sock_hold(sk);
1210                         INIT_DELAYED_WORK(&vsk->dwork,
1211                                           vsock_connect_timeout);
1212                         schedule_delayed_work(&vsk->dwork, timeout);
1213
1214                         /* Skip ahead to preserve error code set above. */
1215                         goto out_wait;
1216                 }
1217
1218                 release_sock(sk);
1219                 timeout = schedule_timeout(timeout);
1220                 lock_sock(sk);
1221
1222                 if (signal_pending(current)) {
1223                         err = sock_intr_errno(timeout);
1224                         goto out_wait_error;
1225                 } else if (timeout == 0) {
1226                         err = -ETIMEDOUT;
1227                         goto out_wait_error;
1228                 }
1229
1230                 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1231         }
1232
1233         if (sk->sk_err) {
1234                 err = -sk->sk_err;
1235                 goto out_wait_error;
1236         } else
1237                 err = 0;
1238
1239 out_wait:
1240         finish_wait(sk_sleep(sk), &wait);
1241 out:
1242         release_sock(sk);
1243         return err;
1244
1245 out_wait_error:
1246         sk->sk_state = SS_UNCONNECTED;
1247         sock->state = SS_UNCONNECTED;
1248         goto out_wait;
1249 }
1250
1251 static int vsock_accept(struct socket *sock, struct socket *newsock, int flags)
1252 {
1253         struct sock *listener;
1254         int err;
1255         struct sock *connected;
1256         struct vsock_sock *vconnected;
1257         long timeout;
1258         DEFINE_WAIT(wait);
1259
1260         err = 0;
1261         listener = sock->sk;
1262
1263         lock_sock(listener);
1264
1265         if (sock->type != SOCK_STREAM) {
1266                 err = -EOPNOTSUPP;
1267                 goto out;
1268         }
1269
1270         if (listener->sk_state != SS_LISTEN) {
1271                 err = -EINVAL;
1272                 goto out;
1273         }
1274
1275         /* Wait for children sockets to appear; these are the new sockets
1276          * created upon connection establishment.
1277          */
1278         timeout = sock_sndtimeo(listener, flags & O_NONBLOCK);
1279         prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE);
1280
1281         while ((connected = vsock_dequeue_accept(listener)) == NULL &&
1282                listener->sk_err == 0) {
1283                 release_sock(listener);
1284                 timeout = schedule_timeout(timeout);
1285                 lock_sock(listener);
1286
1287                 if (signal_pending(current)) {
1288                         err = sock_intr_errno(timeout);
1289                         goto out_wait;
1290                 } else if (timeout == 0) {
1291                         err = -EAGAIN;
1292                         goto out_wait;
1293                 }
1294
1295                 prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE);
1296         }
1297
1298         if (listener->sk_err)
1299                 err = -listener->sk_err;
1300
1301         if (connected) {
1302                 listener->sk_ack_backlog--;
1303
1304                 lock_sock(connected);
1305                 vconnected = vsock_sk(connected);
1306
1307                 /* If the listener socket has received an error, then we should
1308                  * reject this socket and return.  Note that we simply mark the
1309                  * socket rejected, drop our reference, and let the cleanup
1310                  * function handle the cleanup; the fact that we found it in
1311                  * the listener's accept queue guarantees that the cleanup
1312                  * function hasn't run yet.
1313                  */
1314                 if (err) {
1315                         vconnected->rejected = true;
1316                         release_sock(connected);
1317                         sock_put(connected);
1318                         goto out_wait;
1319                 }
1320
1321                 newsock->state = SS_CONNECTED;
1322                 sock_graft(connected, newsock);
1323                 release_sock(connected);
1324                 sock_put(connected);
1325         }
1326
1327 out_wait:
1328         finish_wait(sk_sleep(listener), &wait);
1329 out:
1330         release_sock(listener);
1331         return err;
1332 }
1333
1334 static int vsock_listen(struct socket *sock, int backlog)
1335 {
1336         int err;
1337         struct sock *sk;
1338         struct vsock_sock *vsk;
1339
1340         sk = sock->sk;
1341
1342         lock_sock(sk);
1343
1344         if (sock->type != SOCK_STREAM) {
1345                 err = -EOPNOTSUPP;
1346                 goto out;
1347         }
1348
1349         if (sock->state != SS_UNCONNECTED) {
1350                 err = -EINVAL;
1351                 goto out;
1352         }
1353
1354         vsk = vsock_sk(sk);
1355
1356         if (!vsock_addr_bound(&vsk->local_addr)) {
1357                 err = -EINVAL;
1358                 goto out;
1359         }
1360
1361         sk->sk_max_ack_backlog = backlog;
1362         sk->sk_state = SS_LISTEN;
1363
1364         err = 0;
1365
1366 out:
1367         release_sock(sk);
1368         return err;
1369 }
1370
1371 static int vsock_stream_setsockopt(struct socket *sock,
1372                                    int level,
1373                                    int optname,
1374                                    char __user *optval,
1375                                    unsigned int optlen)
1376 {
1377         int err;
1378         struct sock *sk;
1379         struct vsock_sock *vsk;
1380         u64 val;
1381
1382         if (level != AF_VSOCK)
1383                 return -ENOPROTOOPT;
1384
1385 #define COPY_IN(_v)                                       \
1386         do {                                              \
1387                 if (optlen < sizeof(_v)) {                \
1388                         err = -EINVAL;                    \
1389                         goto exit;                        \
1390                 }                                         \
1391                 if (copy_from_user(&_v, optval, sizeof(_v)) != 0) {     \
1392                         err = -EFAULT;                                  \
1393                         goto exit;                                      \
1394                 }                                                       \
1395         } while (0)
1396
1397         err = 0;
1398         sk = sock->sk;
1399         vsk = vsock_sk(sk);
1400
1401         lock_sock(sk);
1402
1403         switch (optname) {
1404         case SO_VM_SOCKETS_BUFFER_SIZE:
1405                 COPY_IN(val);
1406                 transport->set_buffer_size(vsk, val);
1407                 break;
1408
1409         case SO_VM_SOCKETS_BUFFER_MAX_SIZE:
1410                 COPY_IN(val);
1411                 transport->set_max_buffer_size(vsk, val);
1412                 break;
1413
1414         case SO_VM_SOCKETS_BUFFER_MIN_SIZE:
1415                 COPY_IN(val);
1416                 transport->set_min_buffer_size(vsk, val);
1417                 break;
1418
1419         case SO_VM_SOCKETS_CONNECT_TIMEOUT: {
1420                 struct timeval tv;
1421                 COPY_IN(tv);
1422                 if (tv.tv_sec >= 0 && tv.tv_usec < USEC_PER_SEC &&
1423                     tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)) {
1424                         vsk->connect_timeout = tv.tv_sec * HZ +
1425                             DIV_ROUND_UP(tv.tv_usec, (1000000 / HZ));
1426                         if (vsk->connect_timeout == 0)
1427                                 vsk->connect_timeout =
1428                                     VSOCK_DEFAULT_CONNECT_TIMEOUT;
1429
1430                 } else {
1431                         err = -ERANGE;
1432                 }
1433                 break;
1434         }
1435
1436         default:
1437                 err = -ENOPROTOOPT;
1438                 break;
1439         }
1440
1441 #undef COPY_IN
1442
1443 exit:
1444         release_sock(sk);
1445         return err;
1446 }
1447
1448 static int vsock_stream_getsockopt(struct socket *sock,
1449                                    int level, int optname,
1450                                    char __user *optval,
1451                                    int __user *optlen)
1452 {
1453         int err;
1454         int len;
1455         struct sock *sk;
1456         struct vsock_sock *vsk;
1457         u64 val;
1458
1459         if (level != AF_VSOCK)
1460                 return -ENOPROTOOPT;
1461
1462         err = get_user(len, optlen);
1463         if (err != 0)
1464                 return err;
1465
1466 #define COPY_OUT(_v)                            \
1467         do {                                    \
1468                 if (len < sizeof(_v))           \
1469                         return -EINVAL;         \
1470                                                 \
1471                 len = sizeof(_v);               \
1472                 if (copy_to_user(optval, &_v, len) != 0)        \
1473                         return -EFAULT;                         \
1474                                                                 \
1475         } while (0)
1476
1477         err = 0;
1478         sk = sock->sk;
1479         vsk = vsock_sk(sk);
1480
1481         switch (optname) {
1482         case SO_VM_SOCKETS_BUFFER_SIZE:
1483                 val = transport->get_buffer_size(vsk);
1484                 COPY_OUT(val);
1485                 break;
1486
1487         case SO_VM_SOCKETS_BUFFER_MAX_SIZE:
1488                 val = transport->get_max_buffer_size(vsk);
1489                 COPY_OUT(val);
1490                 break;
1491
1492         case SO_VM_SOCKETS_BUFFER_MIN_SIZE:
1493                 val = transport->get_min_buffer_size(vsk);
1494                 COPY_OUT(val);
1495                 break;
1496
1497         case SO_VM_SOCKETS_CONNECT_TIMEOUT: {
1498                 struct timeval tv;
1499                 tv.tv_sec = vsk->connect_timeout / HZ;
1500                 tv.tv_usec =
1501                     (vsk->connect_timeout -
1502                      tv.tv_sec * HZ) * (1000000 / HZ);
1503                 COPY_OUT(tv);
1504                 break;
1505         }
1506         default:
1507                 return -ENOPROTOOPT;
1508         }
1509
1510         err = put_user(len, optlen);
1511         if (err != 0)
1512                 return -EFAULT;
1513
1514 #undef COPY_OUT
1515
1516         return 0;
1517 }
1518
1519 static int vsock_stream_sendmsg(struct kiocb *kiocb, struct socket *sock,
1520                                 struct msghdr *msg, size_t len)
1521 {
1522         struct sock *sk;
1523         struct vsock_sock *vsk;
1524         ssize_t total_written;
1525         long timeout;
1526         int err;
1527         struct vsock_transport_send_notify_data send_data;
1528
1529         DEFINE_WAIT(wait);
1530
1531         sk = sock->sk;
1532         vsk = vsock_sk(sk);
1533         total_written = 0;
1534         err = 0;
1535
1536         if (msg->msg_flags & MSG_OOB)
1537                 return -EOPNOTSUPP;
1538
1539         lock_sock(sk);
1540
1541         /* Callers should not provide a destination with stream sockets. */
1542         if (msg->msg_namelen) {
1543                 err = sk->sk_state == SS_CONNECTED ? -EISCONN : -EOPNOTSUPP;
1544                 goto out;
1545         }
1546
1547         /* Send data only if both sides are not shutdown in the direction. */
1548         if (sk->sk_shutdown & SEND_SHUTDOWN ||
1549             vsk->peer_shutdown & RCV_SHUTDOWN) {
1550                 err = -EPIPE;
1551                 goto out;
1552         }
1553
1554         if (sk->sk_state != SS_CONNECTED ||
1555             !vsock_addr_bound(&vsk->local_addr)) {
1556                 err = -ENOTCONN;
1557                 goto out;
1558         }
1559
1560         if (!vsock_addr_bound(&vsk->remote_addr)) {
1561                 err = -EDESTADDRREQ;
1562                 goto out;
1563         }
1564
1565         /* Wait for room in the produce queue to enqueue our user's data. */
1566         timeout = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
1567
1568         err = transport->notify_send_init(vsk, &send_data);
1569         if (err < 0)
1570                 goto out;
1571
1572         prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1573
1574         while (total_written < len) {
1575                 ssize_t written;
1576
1577                 while (vsock_stream_has_space(vsk) == 0 &&
1578                        sk->sk_err == 0 &&
1579                        !(sk->sk_shutdown & SEND_SHUTDOWN) &&
1580                        !(vsk->peer_shutdown & RCV_SHUTDOWN)) {
1581
1582                         /* Don't wait for non-blocking sockets. */
1583                         if (timeout == 0) {
1584                                 err = -EAGAIN;
1585                                 goto out_wait;
1586                         }
1587
1588                         err = transport->notify_send_pre_block(vsk, &send_data);
1589                         if (err < 0)
1590                                 goto out_wait;
1591
1592                         release_sock(sk);
1593                         timeout = schedule_timeout(timeout);
1594                         lock_sock(sk);
1595                         if (signal_pending(current)) {
1596                                 err = sock_intr_errno(timeout);
1597                                 goto out_wait;
1598                         } else if (timeout == 0) {
1599                                 err = -EAGAIN;
1600                                 goto out_wait;
1601                         }
1602
1603                         prepare_to_wait(sk_sleep(sk), &wait,
1604                                         TASK_INTERRUPTIBLE);
1605                 }
1606
1607                 /* These checks occur both as part of and after the loop
1608                  * conditional since we need to check before and after
1609                  * sleeping.
1610                  */
1611                 if (sk->sk_err) {
1612                         err = -sk->sk_err;
1613                         goto out_wait;
1614                 } else if ((sk->sk_shutdown & SEND_SHUTDOWN) ||
1615                            (vsk->peer_shutdown & RCV_SHUTDOWN)) {
1616                         err = -EPIPE;
1617                         goto out_wait;
1618                 }
1619
1620                 err = transport->notify_send_pre_enqueue(vsk, &send_data);
1621                 if (err < 0)
1622                         goto out_wait;
1623
1624                 /* Note that enqueue will only write as many bytes as are free
1625                  * in the produce queue, so we don't need to ensure len is
1626                  * smaller than the queue size.  It is the caller's
1627                  * responsibility to check how many bytes we were able to send.
1628                  */
1629
1630                 written = transport->stream_enqueue(
1631                                 vsk, msg->msg_iov,
1632                                 len - total_written);
1633                 if (written < 0) {
1634                         err = -ENOMEM;
1635                         goto out_wait;
1636                 }
1637
1638                 total_written += written;
1639
1640                 err = transport->notify_send_post_enqueue(
1641                                 vsk, written, &send_data);
1642                 if (err < 0)
1643                         goto out_wait;
1644
1645         }
1646
1647 out_wait:
1648         if (total_written > 0)
1649                 err = total_written;
1650         finish_wait(sk_sleep(sk), &wait);
1651 out:
1652         release_sock(sk);
1653         return err;
1654 }
1655
1656
1657 static int
1658 vsock_stream_recvmsg(struct kiocb *kiocb,
1659                      struct socket *sock,
1660                      struct msghdr *msg, size_t len, int flags)
1661 {
1662         struct sock *sk;
1663         struct vsock_sock *vsk;
1664         int err;
1665         size_t target;
1666         ssize_t copied;
1667         long timeout;
1668         struct vsock_transport_recv_notify_data recv_data;
1669
1670         DEFINE_WAIT(wait);
1671
1672         sk = sock->sk;
1673         vsk = vsock_sk(sk);
1674         err = 0;
1675
1676         lock_sock(sk);
1677
1678         if (sk->sk_state != SS_CONNECTED) {
1679                 /* Recvmsg is supposed to return 0 if a peer performs an
1680                  * orderly shutdown. Differentiate between that case and when a
1681                  * peer has not connected or a local shutdown occured with the
1682                  * SOCK_DONE flag.
1683                  */
1684                 if (sock_flag(sk, SOCK_DONE))
1685                         err = 0;
1686                 else
1687                         err = -ENOTCONN;
1688
1689                 goto out;
1690         }
1691
1692         if (flags & MSG_OOB) {
1693                 err = -EOPNOTSUPP;
1694                 goto out;
1695         }
1696
1697         /* We don't check peer_shutdown flag here since peer may actually shut
1698          * down, but there can be data in the queue that a local socket can
1699          * receive.
1700          */
1701         if (sk->sk_shutdown & RCV_SHUTDOWN) {
1702                 err = 0;
1703                 goto out;
1704         }
1705
1706         /* It is valid on Linux to pass in a zero-length receive buffer.  This
1707          * is not an error.  We may as well bail out now.
1708          */
1709         if (!len) {
1710                 err = 0;
1711                 goto out;
1712         }
1713
1714         /* We must not copy less than target bytes into the user's buffer
1715          * before returning successfully, so we wait for the consume queue to
1716          * have that much data to consume before dequeueing.  Note that this
1717          * makes it impossible to handle cases where target is greater than the
1718          * queue size.
1719          */
1720         target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
1721         if (target >= transport->stream_rcvhiwat(vsk)) {
1722                 err = -ENOMEM;
1723                 goto out;
1724         }
1725         timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
1726         copied = 0;
1727
1728         err = transport->notify_recv_init(vsk, target, &recv_data);
1729         if (err < 0)
1730                 goto out;
1731
1732         prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1733
1734         while (1) {
1735                 s64 ready = vsock_stream_has_data(vsk);
1736
1737                 if (ready < 0) {
1738                         /* Invalid queue pair content. XXX This should be
1739                          * changed to a connection reset in a later change.
1740                          */
1741
1742                         err = -ENOMEM;
1743                         goto out_wait;
1744                 } else if (ready > 0) {
1745                         ssize_t read;
1746
1747                         err = transport->notify_recv_pre_dequeue(
1748                                         vsk, target, &recv_data);
1749                         if (err < 0)
1750                                 break;
1751
1752                         read = transport->stream_dequeue(
1753                                         vsk, msg->msg_iov,
1754                                         len - copied, flags);
1755                         if (read < 0) {
1756                                 err = -ENOMEM;
1757                                 break;
1758                         }
1759
1760                         copied += read;
1761
1762                         err = transport->notify_recv_post_dequeue(
1763                                         vsk, target, read,
1764                                         !(flags & MSG_PEEK), &recv_data);
1765                         if (err < 0)
1766                                 goto out_wait;
1767
1768                         if (read >= target || flags & MSG_PEEK)
1769                                 break;
1770
1771                         target -= read;
1772                 } else {
1773                         if (sk->sk_err != 0 || (sk->sk_shutdown & RCV_SHUTDOWN)
1774                             || (vsk->peer_shutdown & SEND_SHUTDOWN)) {
1775                                 break;
1776                         }
1777                         /* Don't wait for non-blocking sockets. */
1778                         if (timeout == 0) {
1779                                 err = -EAGAIN;
1780                                 break;
1781                         }
1782
1783                         err = transport->notify_recv_pre_block(
1784                                         vsk, target, &recv_data);
1785                         if (err < 0)
1786                                 break;
1787
1788                         release_sock(sk);
1789                         timeout = schedule_timeout(timeout);
1790                         lock_sock(sk);
1791
1792                         if (signal_pending(current)) {
1793                                 err = sock_intr_errno(timeout);
1794                                 break;
1795                         } else if (timeout == 0) {
1796                                 err = -EAGAIN;
1797                                 break;
1798                         }
1799
1800                         prepare_to_wait(sk_sleep(sk), &wait,
1801                                         TASK_INTERRUPTIBLE);
1802                 }
1803         }
1804
1805         if (sk->sk_err)
1806                 err = -sk->sk_err;
1807         else if (sk->sk_shutdown & RCV_SHUTDOWN)
1808                 err = 0;
1809
1810         if (copied > 0) {
1811                 /* We only do these additional bookkeeping/notification steps
1812                  * if we actually copied something out of the queue pair
1813                  * instead of just peeking ahead.
1814                  */
1815
1816                 if (!(flags & MSG_PEEK)) {
1817                         /* If the other side has shutdown for sending and there
1818                          * is nothing more to read, then modify the socket
1819                          * state.
1820                          */
1821                         if (vsk->peer_shutdown & SEND_SHUTDOWN) {
1822                                 if (vsock_stream_has_data(vsk) <= 0) {
1823                                         sk->sk_state = SS_UNCONNECTED;
1824                                         sock_set_flag(sk, SOCK_DONE);
1825                                         sk->sk_state_change(sk);
1826                                 }
1827                         }
1828                 }
1829                 err = copied;
1830         }
1831
1832 out_wait:
1833         finish_wait(sk_sleep(sk), &wait);
1834 out:
1835         release_sock(sk);
1836         return err;
1837 }
1838
1839 static const struct proto_ops vsock_stream_ops = {
1840         .family = PF_VSOCK,
1841         .owner = THIS_MODULE,
1842         .release = vsock_release,
1843         .bind = vsock_bind,
1844         .connect = vsock_stream_connect,
1845         .socketpair = sock_no_socketpair,
1846         .accept = vsock_accept,
1847         .getname = vsock_getname,
1848         .poll = vsock_poll,
1849         .ioctl = sock_no_ioctl,
1850         .listen = vsock_listen,
1851         .shutdown = vsock_shutdown,
1852         .setsockopt = vsock_stream_setsockopt,
1853         .getsockopt = vsock_stream_getsockopt,
1854         .sendmsg = vsock_stream_sendmsg,
1855         .recvmsg = vsock_stream_recvmsg,
1856         .mmap = sock_no_mmap,
1857         .sendpage = sock_no_sendpage,
1858 };
1859
1860 static int vsock_create(struct net *net, struct socket *sock,
1861                         int protocol, int kern)
1862 {
1863         if (!sock)
1864                 return -EINVAL;
1865
1866         if (protocol)
1867                 return -EPROTONOSUPPORT;
1868
1869         switch (sock->type) {
1870         case SOCK_DGRAM:
1871                 sock->ops = &vsock_dgram_ops;
1872                 break;
1873         case SOCK_STREAM:
1874                 sock->ops = &vsock_stream_ops;
1875                 break;
1876         default:
1877                 return -ESOCKTNOSUPPORT;
1878         }
1879
1880         sock->state = SS_UNCONNECTED;
1881
1882         return __vsock_create(net, sock, NULL, GFP_KERNEL, 0) ? 0 : -ENOMEM;
1883 }
1884
1885 static const struct net_proto_family vsock_family_ops = {
1886         .family = AF_VSOCK,
1887         .create = vsock_create,
1888         .owner = THIS_MODULE,
1889 };
1890
1891 static long vsock_dev_do_ioctl(struct file *filp,
1892                                unsigned int cmd, void __user *ptr)
1893 {
1894         u32 __user *p = ptr;
1895         int retval = 0;
1896
1897         switch (cmd) {
1898         case IOCTL_VM_SOCKETS_GET_LOCAL_CID:
1899                 if (put_user(transport->get_local_cid(), p) != 0)
1900                         retval = -EFAULT;
1901                 break;
1902
1903         default:
1904                 pr_err("Unknown ioctl %d\n", cmd);
1905                 retval = -EINVAL;
1906         }
1907
1908         return retval;
1909 }
1910
1911 static long vsock_dev_ioctl(struct file *filp,
1912                             unsigned int cmd, unsigned long arg)
1913 {
1914         return vsock_dev_do_ioctl(filp, cmd, (void __user *)arg);
1915 }
1916
1917 #ifdef CONFIG_COMPAT
1918 static long vsock_dev_compat_ioctl(struct file *filp,
1919                                    unsigned int cmd, unsigned long arg)
1920 {
1921         return vsock_dev_do_ioctl(filp, cmd, compat_ptr(arg));
1922 }
1923 #endif
1924
1925 static const struct file_operations vsock_device_ops = {
1926         .owner          = THIS_MODULE,
1927         .unlocked_ioctl = vsock_dev_ioctl,
1928 #ifdef CONFIG_COMPAT
1929         .compat_ioctl   = vsock_dev_compat_ioctl,
1930 #endif
1931         .open           = nonseekable_open,
1932 };
1933
1934 static struct miscdevice vsock_device = {
1935         .name           = "vsock",
1936         .minor          = MISC_DYNAMIC_MINOR,
1937         .fops           = &vsock_device_ops,
1938 };
1939
1940 static int __vsock_core_init(void)
1941 {
1942         int err;
1943
1944         vsock_init_tables();
1945
1946         err = misc_register(&vsock_device);
1947         if (err) {
1948                 pr_err("Failed to register misc device\n");
1949                 return -ENOENT;
1950         }
1951
1952         err = proto_register(&vsock_proto, 1);  /* we want our slab */
1953         if (err) {
1954                 pr_err("Cannot register vsock protocol\n");
1955                 goto err_misc_deregister;
1956         }
1957
1958         err = sock_register(&vsock_family_ops);
1959         if (err) {
1960                 pr_err("could not register af_vsock (%d) address family: %d\n",
1961                        AF_VSOCK, err);
1962                 goto err_unregister_proto;
1963         }
1964
1965         return 0;
1966
1967 err_unregister_proto:
1968         proto_unregister(&vsock_proto);
1969 err_misc_deregister:
1970         misc_deregister(&vsock_device);
1971         return err;
1972 }
1973
1974 int vsock_core_init(const struct vsock_transport *t)
1975 {
1976         int retval = mutex_lock_interruptible(&vsock_register_mutex);
1977         if (retval)
1978                 return retval;
1979
1980         if (transport) {
1981                 retval = -EBUSY;
1982                 goto out;
1983         }
1984
1985         transport = t;
1986         retval = __vsock_core_init();
1987         if (retval)
1988                 transport = NULL;
1989
1990 out:
1991         mutex_unlock(&vsock_register_mutex);
1992         return retval;
1993 }
1994 EXPORT_SYMBOL_GPL(vsock_core_init);
1995
1996 void vsock_core_exit(void)
1997 {
1998         mutex_lock(&vsock_register_mutex);
1999
2000         misc_deregister(&vsock_device);
2001         sock_unregister(AF_VSOCK);
2002         proto_unregister(&vsock_proto);
2003
2004         /* We do not want the assignment below re-ordered. */
2005         mb();
2006         transport = NULL;
2007
2008         mutex_unlock(&vsock_register_mutex);
2009 }
2010 EXPORT_SYMBOL_GPL(vsock_core_exit);
2011
2012 MODULE_AUTHOR("VMware, Inc.");
2013 MODULE_DESCRIPTION("VMware Virtual Socket Family");
2014 MODULE_VERSION(VSOCK_DRIVER_VERSION_STRING);
2015 MODULE_LICENSE("GPL v2");