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