1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * VMware vSockets Driver 4 * 5 * Copyright (C) 2007-2013 VMware, Inc. All rights reserved. 6 */ 7 8 /* Implementation notes: 9 * 10 * - There are two kinds of sockets: those created by user action (such as 11 * calling socket(2)) and those created by incoming connection request packets. 12 * 13 * - There are two "global" tables, one for bound sockets (sockets that have 14 * specified an address that they are responsible for) and one for connected 15 * sockets (sockets that have established a connection with another socket). 16 * These tables are "global" in that all sockets on the system are placed 17 * within them. - Note, though, that the bound table contains an extra entry 18 * for a list of unbound sockets and SOCK_DGRAM sockets will always remain in 19 * that list. The bound table is used solely for lookup of sockets when packets 20 * are received and that's not necessary for SOCK_DGRAM sockets since we create 21 * a datagram handle for each and need not perform a lookup. Keeping SOCK_DGRAM 22 * sockets out of the bound hash buckets will reduce the chance of collisions 23 * when looking for SOCK_STREAM sockets and prevents us from having to check the 24 * socket type in the hash table lookups. 25 * 26 * - Sockets created by user action will either be "client" sockets that 27 * initiate a connection or "server" sockets that listen for connections; we do 28 * not support simultaneous connects (two "client" sockets connecting). 29 * 30 * - "Server" sockets are referred to as listener sockets throughout this 31 * implementation because they are in the TCP_LISTEN state. When a 32 * connection request is received (the second kind of socket mentioned above), 33 * we create a new socket and refer to it as a pending socket. These pending 34 * sockets are placed on the pending connection list of the listener socket. 35 * When future packets are received for the address the listener socket is 36 * bound to, we check if the source of the packet is from one that has an 37 * existing pending connection. If it does, we process the packet for the 38 * pending socket. When that socket reaches the connected state, it is removed 39 * from the listener socket's pending list and enqueued in the listener 40 * socket's accept queue. Callers of accept(2) will accept connected sockets 41 * from the listener socket's accept queue. If the socket cannot be accepted 42 * for some reason then it is marked rejected. Once the connection is 43 * accepted, it is owned by the user process and the responsibility for cleanup 44 * falls with that user process. 45 * 46 * - It is possible that these pending sockets will never reach the connected 47 * state; in fact, we may never receive another packet after the connection 48 * request. Because of this, we must schedule a cleanup function to run in the 49 * future, after some amount of time passes where a connection should have been 50 * established. This function ensures that the socket is off all lists so it 51 * cannot be retrieved, then drops all references to the socket so it is cleaned 52 * up (sock_put() -> sk_free() -> our sk_destruct implementation). Note this 53 * function will also cleanup rejected sockets, those that reach the connected 54 * state but leave it before they have been accepted. 55 * 56 * - Lock ordering for pending or accept queue sockets is: 57 * 58 * lock_sock(listener); 59 * lock_sock_nested(pending, SINGLE_DEPTH_NESTING); 60 * 61 * Using explicit nested locking keeps lockdep happy since normally only one 62 * lock of a given class may be taken at a time. 63 * 64 * - Sockets created by user action will be cleaned up when the user process 65 * calls close(2), causing our release implementation to be called. Our release 66 * implementation will perform some cleanup then drop the last reference so our 67 * sk_destruct implementation is invoked. Our sk_destruct implementation will 68 * perform additional cleanup that's common for both types of sockets. 69 * 70 * - A socket's reference count is what ensures that the structure won't be 71 * freed. Each entry in a list (such as the "global" bound and connected tables 72 * and the listener socket's pending list and connected queue) ensures a 73 * reference. When we defer work until process context and pass a socket as our 74 * argument, we must ensure the reference count is increased to ensure the 75 * socket isn't freed before the function is run; the deferred function will 76 * then drop the reference. 77 * 78 * - sk->sk_state uses the TCP state constants because they are widely used by 79 * other address families and exposed to userspace tools like ss(8): 80 * 81 * TCP_CLOSE - unconnected 82 * TCP_SYN_SENT - connecting 83 * TCP_ESTABLISHED - connected 84 * TCP_CLOSING - disconnecting 85 * TCP_LISTEN - listening 86 */ 87 88 #include <linux/types.h> 89 #include <linux/bitops.h> 90 #include <linux/cred.h> 91 #include <linux/init.h> 92 #include <linux/io.h> 93 #include <linux/kernel.h> 94 #include <linux/sched/signal.h> 95 #include <linux/kmod.h> 96 #include <linux/list.h> 97 #include <linux/miscdevice.h> 98 #include <linux/module.h> 99 #include <linux/mutex.h> 100 #include <linux/net.h> 101 #include <linux/poll.h> 102 #include <linux/random.h> 103 #include <linux/skbuff.h> 104 #include <linux/smp.h> 105 #include <linux/socket.h> 106 #include <linux/stddef.h> 107 #include <linux/unistd.h> 108 #include <linux/wait.h> 109 #include <linux/workqueue.h> 110 #include <net/sock.h> 111 #include <net/af_vsock.h> 112 113 static int __vsock_bind(struct sock *sk, struct sockaddr_vm *addr); 114 static void vsock_sk_destruct(struct sock *sk); 115 static int vsock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); 116 117 /* Protocol family. */ 118 static struct proto vsock_proto = { 119 .name = "AF_VSOCK", 120 .owner = THIS_MODULE, 121 .obj_size = sizeof(struct vsock_sock), 122 }; 123 124 /* The default peer timeout indicates how long we will wait for a peer response 125 * to a control message. 126 */ 127 #define VSOCK_DEFAULT_CONNECT_TIMEOUT (2 * HZ) 128 129 #define VSOCK_DEFAULT_BUFFER_SIZE (1024 * 256) 130 #define VSOCK_DEFAULT_BUFFER_MAX_SIZE (1024 * 256) 131 #define VSOCK_DEFAULT_BUFFER_MIN_SIZE 128 132 133 /* Transport used for host->guest communication */ 134 static const struct vsock_transport *transport_h2g; 135 /* Transport used for guest->host communication */ 136 static const struct vsock_transport *transport_g2h; 137 /* Transport used for DGRAM communication */ 138 static const struct vsock_transport *transport_dgram; 139 /* Transport used for local communication */ 140 static const struct vsock_transport *transport_local; 141 static DEFINE_MUTEX(vsock_register_mutex); 142 143 /**** UTILS ****/ 144 145 /* Each bound VSocket is stored in the bind hash table and each connected 146 * VSocket is stored in the connected hash table. 147 * 148 * Unbound sockets are all put on the same list attached to the end of the hash 149 * table (vsock_unbound_sockets). Bound sockets are added to the hash table in 150 * the bucket that their local address hashes to (vsock_bound_sockets(addr) 151 * represents the list that addr hashes to). 152 * 153 * Specifically, we initialize the vsock_bind_table array to a size of 154 * VSOCK_HASH_SIZE + 1 so that vsock_bind_table[0] through 155 * vsock_bind_table[VSOCK_HASH_SIZE - 1] are for bound sockets and 156 * vsock_bind_table[VSOCK_HASH_SIZE] is for unbound sockets. The hash function 157 * mods with VSOCK_HASH_SIZE to ensure this. 158 */ 159 #define MAX_PORT_RETRIES 24 160 161 #define VSOCK_HASH(addr) ((addr)->svm_port % VSOCK_HASH_SIZE) 162 #define vsock_bound_sockets(addr) (&vsock_bind_table[VSOCK_HASH(addr)]) 163 #define vsock_unbound_sockets (&vsock_bind_table[VSOCK_HASH_SIZE]) 164 165 /* XXX This can probably be implemented in a better way. */ 166 #define VSOCK_CONN_HASH(src, dst) \ 167 (((src)->svm_cid ^ (dst)->svm_port) % VSOCK_HASH_SIZE) 168 #define vsock_connected_sockets(src, dst) \ 169 (&vsock_connected_table[VSOCK_CONN_HASH(src, dst)]) 170 #define vsock_connected_sockets_vsk(vsk) \ 171 vsock_connected_sockets(&(vsk)->remote_addr, &(vsk)->local_addr) 172 173 struct list_head vsock_bind_table[VSOCK_HASH_SIZE + 1]; 174 EXPORT_SYMBOL_GPL(vsock_bind_table); 175 struct list_head vsock_connected_table[VSOCK_HASH_SIZE]; 176 EXPORT_SYMBOL_GPL(vsock_connected_table); 177 DEFINE_SPINLOCK(vsock_table_lock); 178 EXPORT_SYMBOL_GPL(vsock_table_lock); 179 180 /* Autobind this socket to the local address if necessary. */ 181 static int vsock_auto_bind(struct vsock_sock *vsk) 182 { 183 struct sock *sk = sk_vsock(vsk); 184 struct sockaddr_vm local_addr; 185 186 if (vsock_addr_bound(&vsk->local_addr)) 187 return 0; 188 vsock_addr_init(&local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 189 return __vsock_bind(sk, &local_addr); 190 } 191 192 static void vsock_init_tables(void) 193 { 194 int i; 195 196 for (i = 0; i < ARRAY_SIZE(vsock_bind_table); i++) 197 INIT_LIST_HEAD(&vsock_bind_table[i]); 198 199 for (i = 0; i < ARRAY_SIZE(vsock_connected_table); i++) 200 INIT_LIST_HEAD(&vsock_connected_table[i]); 201 } 202 203 static void __vsock_insert_bound(struct list_head *list, 204 struct vsock_sock *vsk) 205 { 206 sock_hold(&vsk->sk); 207 list_add(&vsk->bound_table, list); 208 } 209 210 static void __vsock_insert_connected(struct list_head *list, 211 struct vsock_sock *vsk) 212 { 213 sock_hold(&vsk->sk); 214 list_add(&vsk->connected_table, list); 215 } 216 217 static void __vsock_remove_bound(struct vsock_sock *vsk) 218 { 219 list_del_init(&vsk->bound_table); 220 sock_put(&vsk->sk); 221 } 222 223 static void __vsock_remove_connected(struct vsock_sock *vsk) 224 { 225 list_del_init(&vsk->connected_table); 226 sock_put(&vsk->sk); 227 } 228 229 static struct sock *__vsock_find_bound_socket(struct sockaddr_vm *addr) 230 { 231 struct vsock_sock *vsk; 232 233 list_for_each_entry(vsk, vsock_bound_sockets(addr), bound_table) { 234 if (vsock_addr_equals_addr(addr, &vsk->local_addr)) 235 return sk_vsock(vsk); 236 237 if (addr->svm_port == vsk->local_addr.svm_port && 238 (vsk->local_addr.svm_cid == VMADDR_CID_ANY || 239 addr->svm_cid == VMADDR_CID_ANY)) 240 return sk_vsock(vsk); 241 } 242 243 return NULL; 244 } 245 246 static struct sock *__vsock_find_connected_socket(struct sockaddr_vm *src, 247 struct sockaddr_vm *dst) 248 { 249 struct vsock_sock *vsk; 250 251 list_for_each_entry(vsk, vsock_connected_sockets(src, dst), 252 connected_table) { 253 if (vsock_addr_equals_addr(src, &vsk->remote_addr) && 254 dst->svm_port == vsk->local_addr.svm_port) { 255 return sk_vsock(vsk); 256 } 257 } 258 259 return NULL; 260 } 261 262 static void vsock_insert_unbound(struct vsock_sock *vsk) 263 { 264 spin_lock_bh(&vsock_table_lock); 265 __vsock_insert_bound(vsock_unbound_sockets, vsk); 266 spin_unlock_bh(&vsock_table_lock); 267 } 268 269 void vsock_insert_connected(struct vsock_sock *vsk) 270 { 271 struct list_head *list = vsock_connected_sockets( 272 &vsk->remote_addr, &vsk->local_addr); 273 274 spin_lock_bh(&vsock_table_lock); 275 __vsock_insert_connected(list, vsk); 276 spin_unlock_bh(&vsock_table_lock); 277 } 278 EXPORT_SYMBOL_GPL(vsock_insert_connected); 279 280 void vsock_remove_bound(struct vsock_sock *vsk) 281 { 282 spin_lock_bh(&vsock_table_lock); 283 if (__vsock_in_bound_table(vsk)) 284 __vsock_remove_bound(vsk); 285 spin_unlock_bh(&vsock_table_lock); 286 } 287 EXPORT_SYMBOL_GPL(vsock_remove_bound); 288 289 void vsock_remove_connected(struct vsock_sock *vsk) 290 { 291 spin_lock_bh(&vsock_table_lock); 292 if (__vsock_in_connected_table(vsk)) 293 __vsock_remove_connected(vsk); 294 spin_unlock_bh(&vsock_table_lock); 295 } 296 EXPORT_SYMBOL_GPL(vsock_remove_connected); 297 298 struct sock *vsock_find_bound_socket(struct sockaddr_vm *addr) 299 { 300 struct sock *sk; 301 302 spin_lock_bh(&vsock_table_lock); 303 sk = __vsock_find_bound_socket(addr); 304 if (sk) 305 sock_hold(sk); 306 307 spin_unlock_bh(&vsock_table_lock); 308 309 return sk; 310 } 311 EXPORT_SYMBOL_GPL(vsock_find_bound_socket); 312 313 struct sock *vsock_find_connected_socket(struct sockaddr_vm *src, 314 struct sockaddr_vm *dst) 315 { 316 struct sock *sk; 317 318 spin_lock_bh(&vsock_table_lock); 319 sk = __vsock_find_connected_socket(src, dst); 320 if (sk) 321 sock_hold(sk); 322 323 spin_unlock_bh(&vsock_table_lock); 324 325 return sk; 326 } 327 EXPORT_SYMBOL_GPL(vsock_find_connected_socket); 328 329 void vsock_remove_sock(struct vsock_sock *vsk) 330 { 331 vsock_remove_bound(vsk); 332 vsock_remove_connected(vsk); 333 } 334 EXPORT_SYMBOL_GPL(vsock_remove_sock); 335 336 void vsock_for_each_connected_socket(void (*fn)(struct sock *sk)) 337 { 338 int i; 339 340 spin_lock_bh(&vsock_table_lock); 341 342 for (i = 0; i < ARRAY_SIZE(vsock_connected_table); i++) { 343 struct vsock_sock *vsk; 344 list_for_each_entry(vsk, &vsock_connected_table[i], 345 connected_table) 346 fn(sk_vsock(vsk)); 347 } 348 349 spin_unlock_bh(&vsock_table_lock); 350 } 351 EXPORT_SYMBOL_GPL(vsock_for_each_connected_socket); 352 353 void vsock_add_pending(struct sock *listener, struct sock *pending) 354 { 355 struct vsock_sock *vlistener; 356 struct vsock_sock *vpending; 357 358 vlistener = vsock_sk(listener); 359 vpending = vsock_sk(pending); 360 361 sock_hold(pending); 362 sock_hold(listener); 363 list_add_tail(&vpending->pending_links, &vlistener->pending_links); 364 } 365 EXPORT_SYMBOL_GPL(vsock_add_pending); 366 367 void vsock_remove_pending(struct sock *listener, struct sock *pending) 368 { 369 struct vsock_sock *vpending = vsock_sk(pending); 370 371 list_del_init(&vpending->pending_links); 372 sock_put(listener); 373 sock_put(pending); 374 } 375 EXPORT_SYMBOL_GPL(vsock_remove_pending); 376 377 void vsock_enqueue_accept(struct sock *listener, struct sock *connected) 378 { 379 struct vsock_sock *vlistener; 380 struct vsock_sock *vconnected; 381 382 vlistener = vsock_sk(listener); 383 vconnected = vsock_sk(connected); 384 385 sock_hold(connected); 386 sock_hold(listener); 387 list_add_tail(&vconnected->accept_queue, &vlistener->accept_queue); 388 } 389 EXPORT_SYMBOL_GPL(vsock_enqueue_accept); 390 391 static bool vsock_use_local_transport(unsigned int remote_cid) 392 { 393 if (!transport_local) 394 return false; 395 396 if (remote_cid == VMADDR_CID_LOCAL) 397 return true; 398 399 if (transport_g2h) { 400 return remote_cid == transport_g2h->get_local_cid(); 401 } else { 402 return remote_cid == VMADDR_CID_HOST; 403 } 404 } 405 406 static void vsock_deassign_transport(struct vsock_sock *vsk) 407 { 408 if (!vsk->transport) 409 return; 410 411 vsk->transport->destruct(vsk); 412 module_put(vsk->transport->module); 413 vsk->transport = NULL; 414 } 415 416 /* Assign a transport to a socket and call the .init transport callback. 417 * 418 * Note: for stream socket this must be called when vsk->remote_addr is set 419 * (e.g. during the connect() or when a connection request on a listener 420 * socket is received). 421 * The vsk->remote_addr is used to decide which transport to use: 422 * - remote CID == VMADDR_CID_LOCAL or g2h->local_cid or VMADDR_CID_HOST if 423 * g2h is not loaded, will use local transport; 424 * - remote CID <= VMADDR_CID_HOST or h2g is not loaded or remote flags field 425 * includes VMADDR_FLAG_TO_HOST flag value, will use guest->host transport; 426 * - remote CID > VMADDR_CID_HOST will use host->guest transport; 427 */ 428 int vsock_assign_transport(struct vsock_sock *vsk, struct vsock_sock *psk) 429 { 430 const struct vsock_transport *new_transport; 431 struct sock *sk = sk_vsock(vsk); 432 unsigned int remote_cid = vsk->remote_addr.svm_cid; 433 __u8 remote_flags; 434 int ret; 435 436 /* If the packet is coming with the source and destination CIDs higher 437 * than VMADDR_CID_HOST, then a vsock channel where all the packets are 438 * forwarded to the host should be established. Then the host will 439 * need to forward the packets to the guest. 440 * 441 * The flag is set on the (listen) receive path (psk is not NULL). On 442 * the connect path the flag can be set by the user space application. 443 */ 444 if (psk && vsk->local_addr.svm_cid > VMADDR_CID_HOST && 445 vsk->remote_addr.svm_cid > VMADDR_CID_HOST) 446 vsk->remote_addr.svm_flags |= VMADDR_FLAG_TO_HOST; 447 448 remote_flags = vsk->remote_addr.svm_flags; 449 450 switch (sk->sk_type) { 451 case SOCK_DGRAM: 452 new_transport = transport_dgram; 453 break; 454 case SOCK_STREAM: 455 if (vsock_use_local_transport(remote_cid)) 456 new_transport = transport_local; 457 else if (remote_cid <= VMADDR_CID_HOST || !transport_h2g || 458 (remote_flags & VMADDR_FLAG_TO_HOST)) 459 new_transport = transport_g2h; 460 else 461 new_transport = transport_h2g; 462 break; 463 default: 464 return -ESOCKTNOSUPPORT; 465 } 466 467 if (vsk->transport) { 468 if (vsk->transport == new_transport) 469 return 0; 470 471 /* transport->release() must be called with sock lock acquired. 472 * This path can only be taken during vsock_stream_connect(), 473 * where we have already held the sock lock. 474 * In the other cases, this function is called on a new socket 475 * which is not assigned to any transport. 476 */ 477 vsk->transport->release(vsk); 478 vsock_deassign_transport(vsk); 479 } 480 481 /* We increase the module refcnt to prevent the transport unloading 482 * while there are open sockets assigned to it. 483 */ 484 if (!new_transport || !try_module_get(new_transport->module)) 485 return -ENODEV; 486 487 ret = new_transport->init(vsk, psk); 488 if (ret) { 489 module_put(new_transport->module); 490 return ret; 491 } 492 493 vsk->transport = new_transport; 494 495 return 0; 496 } 497 EXPORT_SYMBOL_GPL(vsock_assign_transport); 498 499 bool vsock_find_cid(unsigned int cid) 500 { 501 if (transport_g2h && cid == transport_g2h->get_local_cid()) 502 return true; 503 504 if (transport_h2g && cid == VMADDR_CID_HOST) 505 return true; 506 507 if (transport_local && cid == VMADDR_CID_LOCAL) 508 return true; 509 510 return false; 511 } 512 EXPORT_SYMBOL_GPL(vsock_find_cid); 513 514 static struct sock *vsock_dequeue_accept(struct sock *listener) 515 { 516 struct vsock_sock *vlistener; 517 struct vsock_sock *vconnected; 518 519 vlistener = vsock_sk(listener); 520 521 if (list_empty(&vlistener->accept_queue)) 522 return NULL; 523 524 vconnected = list_entry(vlistener->accept_queue.next, 525 struct vsock_sock, accept_queue); 526 527 list_del_init(&vconnected->accept_queue); 528 sock_put(listener); 529 /* The caller will need a reference on the connected socket so we let 530 * it call sock_put(). 531 */ 532 533 return sk_vsock(vconnected); 534 } 535 536 static bool vsock_is_accept_queue_empty(struct sock *sk) 537 { 538 struct vsock_sock *vsk = vsock_sk(sk); 539 return list_empty(&vsk->accept_queue); 540 } 541 542 static bool vsock_is_pending(struct sock *sk) 543 { 544 struct vsock_sock *vsk = vsock_sk(sk); 545 return !list_empty(&vsk->pending_links); 546 } 547 548 static int vsock_send_shutdown(struct sock *sk, int mode) 549 { 550 struct vsock_sock *vsk = vsock_sk(sk); 551 552 if (!vsk->transport) 553 return -ENODEV; 554 555 return vsk->transport->shutdown(vsk, mode); 556 } 557 558 static void vsock_pending_work(struct work_struct *work) 559 { 560 struct sock *sk; 561 struct sock *listener; 562 struct vsock_sock *vsk; 563 bool cleanup; 564 565 vsk = container_of(work, struct vsock_sock, pending_work.work); 566 sk = sk_vsock(vsk); 567 listener = vsk->listener; 568 cleanup = true; 569 570 lock_sock(listener); 571 lock_sock_nested(sk, SINGLE_DEPTH_NESTING); 572 573 if (vsock_is_pending(sk)) { 574 vsock_remove_pending(listener, sk); 575 576 sk_acceptq_removed(listener); 577 } else if (!vsk->rejected) { 578 /* We are not on the pending list and accept() did not reject 579 * us, so we must have been accepted by our user process. We 580 * just need to drop our references to the sockets and be on 581 * our way. 582 */ 583 cleanup = false; 584 goto out; 585 } 586 587 /* We need to remove ourself from the global connected sockets list so 588 * incoming packets can't find this socket, and to reduce the reference 589 * count. 590 */ 591 vsock_remove_connected(vsk); 592 593 sk->sk_state = TCP_CLOSE; 594 595 out: 596 release_sock(sk); 597 release_sock(listener); 598 if (cleanup) 599 sock_put(sk); 600 601 sock_put(sk); 602 sock_put(listener); 603 } 604 605 /**** SOCKET OPERATIONS ****/ 606 607 static int __vsock_bind_stream(struct vsock_sock *vsk, 608 struct sockaddr_vm *addr) 609 { 610 static u32 port; 611 struct sockaddr_vm new_addr; 612 613 if (!port) 614 port = LAST_RESERVED_PORT + 1 + 615 prandom_u32_max(U32_MAX - LAST_RESERVED_PORT); 616 617 vsock_addr_init(&new_addr, addr->svm_cid, addr->svm_port); 618 619 if (addr->svm_port == VMADDR_PORT_ANY) { 620 bool found = false; 621 unsigned int i; 622 623 for (i = 0; i < MAX_PORT_RETRIES; i++) { 624 if (port <= LAST_RESERVED_PORT) 625 port = LAST_RESERVED_PORT + 1; 626 627 new_addr.svm_port = port++; 628 629 if (!__vsock_find_bound_socket(&new_addr)) { 630 found = true; 631 break; 632 } 633 } 634 635 if (!found) 636 return -EADDRNOTAVAIL; 637 } else { 638 /* If port is in reserved range, ensure caller 639 * has necessary privileges. 640 */ 641 if (addr->svm_port <= LAST_RESERVED_PORT && 642 !capable(CAP_NET_BIND_SERVICE)) { 643 return -EACCES; 644 } 645 646 if (__vsock_find_bound_socket(&new_addr)) 647 return -EADDRINUSE; 648 } 649 650 vsock_addr_init(&vsk->local_addr, new_addr.svm_cid, new_addr.svm_port); 651 652 /* Remove stream sockets from the unbound list and add them to the hash 653 * table for easy lookup by its address. The unbound list is simply an 654 * extra entry at the end of the hash table, a trick used by AF_UNIX. 655 */ 656 __vsock_remove_bound(vsk); 657 __vsock_insert_bound(vsock_bound_sockets(&vsk->local_addr), vsk); 658 659 return 0; 660 } 661 662 static int __vsock_bind_dgram(struct vsock_sock *vsk, 663 struct sockaddr_vm *addr) 664 { 665 return vsk->transport->dgram_bind(vsk, addr); 666 } 667 668 static int __vsock_bind(struct sock *sk, struct sockaddr_vm *addr) 669 { 670 struct vsock_sock *vsk = vsock_sk(sk); 671 int retval; 672 673 /* First ensure this socket isn't already bound. */ 674 if (vsock_addr_bound(&vsk->local_addr)) 675 return -EINVAL; 676 677 /* Now bind to the provided address or select appropriate values if 678 * none are provided (VMADDR_CID_ANY and VMADDR_PORT_ANY). Note that 679 * like AF_INET prevents binding to a non-local IP address (in most 680 * cases), we only allow binding to a local CID. 681 */ 682 if (addr->svm_cid != VMADDR_CID_ANY && !vsock_find_cid(addr->svm_cid)) 683 return -EADDRNOTAVAIL; 684 685 switch (sk->sk_socket->type) { 686 case SOCK_STREAM: 687 spin_lock_bh(&vsock_table_lock); 688 retval = __vsock_bind_stream(vsk, addr); 689 spin_unlock_bh(&vsock_table_lock); 690 break; 691 692 case SOCK_DGRAM: 693 retval = __vsock_bind_dgram(vsk, addr); 694 break; 695 696 default: 697 retval = -EINVAL; 698 break; 699 } 700 701 return retval; 702 } 703 704 static void vsock_connect_timeout(struct work_struct *work); 705 706 static struct sock *__vsock_create(struct net *net, 707 struct socket *sock, 708 struct sock *parent, 709 gfp_t priority, 710 unsigned short type, 711 int kern) 712 { 713 struct sock *sk; 714 struct vsock_sock *psk; 715 struct vsock_sock *vsk; 716 717 sk = sk_alloc(net, AF_VSOCK, priority, &vsock_proto, kern); 718 if (!sk) 719 return NULL; 720 721 sock_init_data(sock, sk); 722 723 /* sk->sk_type is normally set in sock_init_data, but only if sock is 724 * non-NULL. We make sure that our sockets always have a type by 725 * setting it here if needed. 726 */ 727 if (!sock) 728 sk->sk_type = type; 729 730 vsk = vsock_sk(sk); 731 vsock_addr_init(&vsk->local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 732 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 733 734 sk->sk_destruct = vsock_sk_destruct; 735 sk->sk_backlog_rcv = vsock_queue_rcv_skb; 736 sock_reset_flag(sk, SOCK_DONE); 737 738 INIT_LIST_HEAD(&vsk->bound_table); 739 INIT_LIST_HEAD(&vsk->connected_table); 740 vsk->listener = NULL; 741 INIT_LIST_HEAD(&vsk->pending_links); 742 INIT_LIST_HEAD(&vsk->accept_queue); 743 vsk->rejected = false; 744 vsk->sent_request = false; 745 vsk->ignore_connecting_rst = false; 746 vsk->peer_shutdown = 0; 747 INIT_DELAYED_WORK(&vsk->connect_work, vsock_connect_timeout); 748 INIT_DELAYED_WORK(&vsk->pending_work, vsock_pending_work); 749 750 psk = parent ? vsock_sk(parent) : NULL; 751 if (parent) { 752 vsk->trusted = psk->trusted; 753 vsk->owner = get_cred(psk->owner); 754 vsk->connect_timeout = psk->connect_timeout; 755 vsk->buffer_size = psk->buffer_size; 756 vsk->buffer_min_size = psk->buffer_min_size; 757 vsk->buffer_max_size = psk->buffer_max_size; 758 } else { 759 vsk->trusted = ns_capable_noaudit(&init_user_ns, CAP_NET_ADMIN); 760 vsk->owner = get_current_cred(); 761 vsk->connect_timeout = VSOCK_DEFAULT_CONNECT_TIMEOUT; 762 vsk->buffer_size = VSOCK_DEFAULT_BUFFER_SIZE; 763 vsk->buffer_min_size = VSOCK_DEFAULT_BUFFER_MIN_SIZE; 764 vsk->buffer_max_size = VSOCK_DEFAULT_BUFFER_MAX_SIZE; 765 } 766 767 return sk; 768 } 769 770 static void __vsock_release(struct sock *sk, int level) 771 { 772 if (sk) { 773 struct sock *pending; 774 struct vsock_sock *vsk; 775 776 vsk = vsock_sk(sk); 777 pending = NULL; /* Compiler warning. */ 778 779 /* When "level" is SINGLE_DEPTH_NESTING, use the nested 780 * version to avoid the warning "possible recursive locking 781 * detected". When "level" is 0, lock_sock_nested(sk, level) 782 * is the same as lock_sock(sk). 783 */ 784 lock_sock_nested(sk, level); 785 786 if (vsk->transport) 787 vsk->transport->release(vsk); 788 else if (sk->sk_type == SOCK_STREAM) 789 vsock_remove_sock(vsk); 790 791 sock_orphan(sk); 792 sk->sk_shutdown = SHUTDOWN_MASK; 793 794 skb_queue_purge(&sk->sk_receive_queue); 795 796 /* Clean up any sockets that never were accepted. */ 797 while ((pending = vsock_dequeue_accept(sk)) != NULL) { 798 __vsock_release(pending, SINGLE_DEPTH_NESTING); 799 sock_put(pending); 800 } 801 802 release_sock(sk); 803 sock_put(sk); 804 } 805 } 806 807 static void vsock_sk_destruct(struct sock *sk) 808 { 809 struct vsock_sock *vsk = vsock_sk(sk); 810 811 vsock_deassign_transport(vsk); 812 813 /* When clearing these addresses, there's no need to set the family and 814 * possibly register the address family with the kernel. 815 */ 816 vsock_addr_init(&vsk->local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 817 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 818 819 put_cred(vsk->owner); 820 } 821 822 static int vsock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 823 { 824 int err; 825 826 err = sock_queue_rcv_skb(sk, skb); 827 if (err) 828 kfree_skb(skb); 829 830 return err; 831 } 832 833 struct sock *vsock_create_connected(struct sock *parent) 834 { 835 return __vsock_create(sock_net(parent), NULL, parent, GFP_KERNEL, 836 parent->sk_type, 0); 837 } 838 EXPORT_SYMBOL_GPL(vsock_create_connected); 839 840 s64 vsock_stream_has_data(struct vsock_sock *vsk) 841 { 842 return vsk->transport->stream_has_data(vsk); 843 } 844 EXPORT_SYMBOL_GPL(vsock_stream_has_data); 845 846 s64 vsock_stream_has_space(struct vsock_sock *vsk) 847 { 848 return vsk->transport->stream_has_space(vsk); 849 } 850 EXPORT_SYMBOL_GPL(vsock_stream_has_space); 851 852 static int vsock_release(struct socket *sock) 853 { 854 __vsock_release(sock->sk, 0); 855 sock->sk = NULL; 856 sock->state = SS_FREE; 857 858 return 0; 859 } 860 861 static int 862 vsock_bind(struct socket *sock, struct sockaddr *addr, int addr_len) 863 { 864 int err; 865 struct sock *sk; 866 struct sockaddr_vm *vm_addr; 867 868 sk = sock->sk; 869 870 if (vsock_addr_cast(addr, addr_len, &vm_addr) != 0) 871 return -EINVAL; 872 873 lock_sock(sk); 874 err = __vsock_bind(sk, vm_addr); 875 release_sock(sk); 876 877 return err; 878 } 879 880 static int vsock_getname(struct socket *sock, 881 struct sockaddr *addr, int peer) 882 { 883 int err; 884 struct sock *sk; 885 struct vsock_sock *vsk; 886 struct sockaddr_vm *vm_addr; 887 888 sk = sock->sk; 889 vsk = vsock_sk(sk); 890 err = 0; 891 892 lock_sock(sk); 893 894 if (peer) { 895 if (sock->state != SS_CONNECTED) { 896 err = -ENOTCONN; 897 goto out; 898 } 899 vm_addr = &vsk->remote_addr; 900 } else { 901 vm_addr = &vsk->local_addr; 902 } 903 904 if (!vm_addr) { 905 err = -EINVAL; 906 goto out; 907 } 908 909 /* sys_getsockname() and sys_getpeername() pass us a 910 * MAX_SOCK_ADDR-sized buffer and don't set addr_len. Unfortunately 911 * that macro is defined in socket.c instead of .h, so we hardcode its 912 * value here. 913 */ 914 BUILD_BUG_ON(sizeof(*vm_addr) > 128); 915 memcpy(addr, vm_addr, sizeof(*vm_addr)); 916 err = sizeof(*vm_addr); 917 918 out: 919 release_sock(sk); 920 return err; 921 } 922 923 static int vsock_shutdown(struct socket *sock, int mode) 924 { 925 int err; 926 struct sock *sk; 927 928 /* User level uses SHUT_RD (0) and SHUT_WR (1), but the kernel uses 929 * RCV_SHUTDOWN (1) and SEND_SHUTDOWN (2), so we must increment mode 930 * here like the other address families do. Note also that the 931 * increment makes SHUT_RDWR (2) into RCV_SHUTDOWN | SEND_SHUTDOWN (3), 932 * which is what we want. 933 */ 934 mode++; 935 936 if ((mode & ~SHUTDOWN_MASK) || !mode) 937 return -EINVAL; 938 939 /* If this is a STREAM socket and it is not connected then bail out 940 * immediately. If it is a DGRAM socket then we must first kick the 941 * socket so that it wakes up from any sleeping calls, for example 942 * recv(), and then afterwards return the error. 943 */ 944 945 sk = sock->sk; 946 947 lock_sock(sk); 948 if (sock->state == SS_UNCONNECTED) { 949 err = -ENOTCONN; 950 if (sk->sk_type == SOCK_STREAM) 951 goto out; 952 } else { 953 sock->state = SS_DISCONNECTING; 954 err = 0; 955 } 956 957 /* Receive and send shutdowns are treated alike. */ 958 mode = mode & (RCV_SHUTDOWN | SEND_SHUTDOWN); 959 if (mode) { 960 sk->sk_shutdown |= mode; 961 sk->sk_state_change(sk); 962 963 if (sk->sk_type == SOCK_STREAM) { 964 sock_reset_flag(sk, SOCK_DONE); 965 vsock_send_shutdown(sk, mode); 966 } 967 } 968 969 out: 970 release_sock(sk); 971 return err; 972 } 973 974 static __poll_t vsock_poll(struct file *file, struct socket *sock, 975 poll_table *wait) 976 { 977 struct sock *sk; 978 __poll_t mask; 979 struct vsock_sock *vsk; 980 981 sk = sock->sk; 982 vsk = vsock_sk(sk); 983 984 poll_wait(file, sk_sleep(sk), wait); 985 mask = 0; 986 987 if (sk->sk_err) 988 /* Signify that there has been an error on this socket. */ 989 mask |= EPOLLERR; 990 991 /* INET sockets treat local write shutdown and peer write shutdown as a 992 * case of EPOLLHUP set. 993 */ 994 if ((sk->sk_shutdown == SHUTDOWN_MASK) || 995 ((sk->sk_shutdown & SEND_SHUTDOWN) && 996 (vsk->peer_shutdown & SEND_SHUTDOWN))) { 997 mask |= EPOLLHUP; 998 } 999 1000 if (sk->sk_shutdown & RCV_SHUTDOWN || 1001 vsk->peer_shutdown & SEND_SHUTDOWN) { 1002 mask |= EPOLLRDHUP; 1003 } 1004 1005 if (sock->type == SOCK_DGRAM) { 1006 /* For datagram sockets we can read if there is something in 1007 * the queue and write as long as the socket isn't shutdown for 1008 * sending. 1009 */ 1010 if (!skb_queue_empty_lockless(&sk->sk_receive_queue) || 1011 (sk->sk_shutdown & RCV_SHUTDOWN)) { 1012 mask |= EPOLLIN | EPOLLRDNORM; 1013 } 1014 1015 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) 1016 mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND; 1017 1018 } else if (sock->type == SOCK_STREAM) { 1019 const struct vsock_transport *transport; 1020 1021 lock_sock(sk); 1022 1023 transport = vsk->transport; 1024 1025 /* Listening sockets that have connections in their accept 1026 * queue can be read. 1027 */ 1028 if (sk->sk_state == TCP_LISTEN 1029 && !vsock_is_accept_queue_empty(sk)) 1030 mask |= EPOLLIN | EPOLLRDNORM; 1031 1032 /* If there is something in the queue then we can read. */ 1033 if (transport && transport->stream_is_active(vsk) && 1034 !(sk->sk_shutdown & RCV_SHUTDOWN)) { 1035 bool data_ready_now = false; 1036 int ret = transport->notify_poll_in( 1037 vsk, 1, &data_ready_now); 1038 if (ret < 0) { 1039 mask |= EPOLLERR; 1040 } else { 1041 if (data_ready_now) 1042 mask |= EPOLLIN | EPOLLRDNORM; 1043 1044 } 1045 } 1046 1047 /* Sockets whose connections have been closed, reset, or 1048 * terminated should also be considered read, and we check the 1049 * shutdown flag for that. 1050 */ 1051 if (sk->sk_shutdown & RCV_SHUTDOWN || 1052 vsk->peer_shutdown & SEND_SHUTDOWN) { 1053 mask |= EPOLLIN | EPOLLRDNORM; 1054 } 1055 1056 /* Connected sockets that can produce data can be written. */ 1057 if (transport && sk->sk_state == TCP_ESTABLISHED) { 1058 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) { 1059 bool space_avail_now = false; 1060 int ret = transport->notify_poll_out( 1061 vsk, 1, &space_avail_now); 1062 if (ret < 0) { 1063 mask |= EPOLLERR; 1064 } else { 1065 if (space_avail_now) 1066 /* Remove EPOLLWRBAND since INET 1067 * sockets are not setting it. 1068 */ 1069 mask |= EPOLLOUT | EPOLLWRNORM; 1070 1071 } 1072 } 1073 } 1074 1075 /* Simulate INET socket poll behaviors, which sets 1076 * EPOLLOUT|EPOLLWRNORM when peer is closed and nothing to read, 1077 * but local send is not shutdown. 1078 */ 1079 if (sk->sk_state == TCP_CLOSE || sk->sk_state == TCP_CLOSING) { 1080 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) 1081 mask |= EPOLLOUT | EPOLLWRNORM; 1082 1083 } 1084 1085 release_sock(sk); 1086 } 1087 1088 return mask; 1089 } 1090 1091 static int vsock_dgram_sendmsg(struct socket *sock, struct msghdr *msg, 1092 size_t len) 1093 { 1094 int err; 1095 struct sock *sk; 1096 struct vsock_sock *vsk; 1097 struct sockaddr_vm *remote_addr; 1098 const struct vsock_transport *transport; 1099 1100 if (msg->msg_flags & MSG_OOB) 1101 return -EOPNOTSUPP; 1102 1103 /* For now, MSG_DONTWAIT is always assumed... */ 1104 err = 0; 1105 sk = sock->sk; 1106 vsk = vsock_sk(sk); 1107 1108 lock_sock(sk); 1109 1110 transport = vsk->transport; 1111 1112 err = vsock_auto_bind(vsk); 1113 if (err) 1114 goto out; 1115 1116 1117 /* If the provided message contains an address, use that. Otherwise 1118 * fall back on the socket's remote handle (if it has been connected). 1119 */ 1120 if (msg->msg_name && 1121 vsock_addr_cast(msg->msg_name, msg->msg_namelen, 1122 &remote_addr) == 0) { 1123 /* Ensure this address is of the right type and is a valid 1124 * destination. 1125 */ 1126 1127 if (remote_addr->svm_cid == VMADDR_CID_ANY) 1128 remote_addr->svm_cid = transport->get_local_cid(); 1129 1130 if (!vsock_addr_bound(remote_addr)) { 1131 err = -EINVAL; 1132 goto out; 1133 } 1134 } else if (sock->state == SS_CONNECTED) { 1135 remote_addr = &vsk->remote_addr; 1136 1137 if (remote_addr->svm_cid == VMADDR_CID_ANY) 1138 remote_addr->svm_cid = transport->get_local_cid(); 1139 1140 /* XXX Should connect() or this function ensure remote_addr is 1141 * bound? 1142 */ 1143 if (!vsock_addr_bound(&vsk->remote_addr)) { 1144 err = -EINVAL; 1145 goto out; 1146 } 1147 } else { 1148 err = -EINVAL; 1149 goto out; 1150 } 1151 1152 if (!transport->dgram_allow(remote_addr->svm_cid, 1153 remote_addr->svm_port)) { 1154 err = -EINVAL; 1155 goto out; 1156 } 1157 1158 err = transport->dgram_enqueue(vsk, remote_addr, msg, len); 1159 1160 out: 1161 release_sock(sk); 1162 return err; 1163 } 1164 1165 static int vsock_dgram_connect(struct socket *sock, 1166 struct sockaddr *addr, int addr_len, int flags) 1167 { 1168 int err; 1169 struct sock *sk; 1170 struct vsock_sock *vsk; 1171 struct sockaddr_vm *remote_addr; 1172 1173 sk = sock->sk; 1174 vsk = vsock_sk(sk); 1175 1176 err = vsock_addr_cast(addr, addr_len, &remote_addr); 1177 if (err == -EAFNOSUPPORT && remote_addr->svm_family == AF_UNSPEC) { 1178 lock_sock(sk); 1179 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, 1180 VMADDR_PORT_ANY); 1181 sock->state = SS_UNCONNECTED; 1182 release_sock(sk); 1183 return 0; 1184 } else if (err != 0) 1185 return -EINVAL; 1186 1187 lock_sock(sk); 1188 1189 err = vsock_auto_bind(vsk); 1190 if (err) 1191 goto out; 1192 1193 if (!vsk->transport->dgram_allow(remote_addr->svm_cid, 1194 remote_addr->svm_port)) { 1195 err = -EINVAL; 1196 goto out; 1197 } 1198 1199 memcpy(&vsk->remote_addr, remote_addr, sizeof(vsk->remote_addr)); 1200 sock->state = SS_CONNECTED; 1201 1202 out: 1203 release_sock(sk); 1204 return err; 1205 } 1206 1207 static int vsock_dgram_recvmsg(struct socket *sock, struct msghdr *msg, 1208 size_t len, int flags) 1209 { 1210 struct vsock_sock *vsk = vsock_sk(sock->sk); 1211 1212 return vsk->transport->dgram_dequeue(vsk, msg, len, flags); 1213 } 1214 1215 static const struct proto_ops vsock_dgram_ops = { 1216 .family = PF_VSOCK, 1217 .owner = THIS_MODULE, 1218 .release = vsock_release, 1219 .bind = vsock_bind, 1220 .connect = vsock_dgram_connect, 1221 .socketpair = sock_no_socketpair, 1222 .accept = sock_no_accept, 1223 .getname = vsock_getname, 1224 .poll = vsock_poll, 1225 .ioctl = sock_no_ioctl, 1226 .listen = sock_no_listen, 1227 .shutdown = vsock_shutdown, 1228 .sendmsg = vsock_dgram_sendmsg, 1229 .recvmsg = vsock_dgram_recvmsg, 1230 .mmap = sock_no_mmap, 1231 .sendpage = sock_no_sendpage, 1232 }; 1233 1234 static int vsock_transport_cancel_pkt(struct vsock_sock *vsk) 1235 { 1236 const struct vsock_transport *transport = vsk->transport; 1237 1238 if (!transport || !transport->cancel_pkt) 1239 return -EOPNOTSUPP; 1240 1241 return transport->cancel_pkt(vsk); 1242 } 1243 1244 static void vsock_connect_timeout(struct work_struct *work) 1245 { 1246 struct sock *sk; 1247 struct vsock_sock *vsk; 1248 1249 vsk = container_of(work, struct vsock_sock, connect_work.work); 1250 sk = sk_vsock(vsk); 1251 1252 lock_sock(sk); 1253 if (sk->sk_state == TCP_SYN_SENT && 1254 (sk->sk_shutdown != SHUTDOWN_MASK)) { 1255 sk->sk_state = TCP_CLOSE; 1256 sk->sk_err = ETIMEDOUT; 1257 sk->sk_error_report(sk); 1258 vsock_transport_cancel_pkt(vsk); 1259 } 1260 release_sock(sk); 1261 1262 sock_put(sk); 1263 } 1264 1265 static int vsock_stream_connect(struct socket *sock, struct sockaddr *addr, 1266 int addr_len, int flags) 1267 { 1268 int err; 1269 struct sock *sk; 1270 struct vsock_sock *vsk; 1271 const struct vsock_transport *transport; 1272 struct sockaddr_vm *remote_addr; 1273 long timeout; 1274 DEFINE_WAIT(wait); 1275 1276 err = 0; 1277 sk = sock->sk; 1278 vsk = vsock_sk(sk); 1279 1280 lock_sock(sk); 1281 1282 /* XXX AF_UNSPEC should make us disconnect like AF_INET. */ 1283 switch (sock->state) { 1284 case SS_CONNECTED: 1285 err = -EISCONN; 1286 goto out; 1287 case SS_DISCONNECTING: 1288 err = -EINVAL; 1289 goto out; 1290 case SS_CONNECTING: 1291 /* This continues on so we can move sock into the SS_CONNECTED 1292 * state once the connection has completed (at which point err 1293 * will be set to zero also). Otherwise, we will either wait 1294 * for the connection or return -EALREADY should this be a 1295 * non-blocking call. 1296 */ 1297 err = -EALREADY; 1298 break; 1299 default: 1300 if ((sk->sk_state == TCP_LISTEN) || 1301 vsock_addr_cast(addr, addr_len, &remote_addr) != 0) { 1302 err = -EINVAL; 1303 goto out; 1304 } 1305 1306 /* Set the remote address that we are connecting to. */ 1307 memcpy(&vsk->remote_addr, remote_addr, 1308 sizeof(vsk->remote_addr)); 1309 1310 err = vsock_assign_transport(vsk, NULL); 1311 if (err) 1312 goto out; 1313 1314 transport = vsk->transport; 1315 1316 /* The hypervisor and well-known contexts do not have socket 1317 * endpoints. 1318 */ 1319 if (!transport || 1320 !transport->stream_allow(remote_addr->svm_cid, 1321 remote_addr->svm_port)) { 1322 err = -ENETUNREACH; 1323 goto out; 1324 } 1325 1326 err = vsock_auto_bind(vsk); 1327 if (err) 1328 goto out; 1329 1330 sk->sk_state = TCP_SYN_SENT; 1331 1332 err = transport->connect(vsk); 1333 if (err < 0) 1334 goto out; 1335 1336 /* Mark sock as connecting and set the error code to in 1337 * progress in case this is a non-blocking connect. 1338 */ 1339 sock->state = SS_CONNECTING; 1340 err = -EINPROGRESS; 1341 } 1342 1343 /* The receive path will handle all communication until we are able to 1344 * enter the connected state. Here we wait for the connection to be 1345 * completed or a notification of an error. 1346 */ 1347 timeout = vsk->connect_timeout; 1348 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1349 1350 while (sk->sk_state != TCP_ESTABLISHED && sk->sk_err == 0) { 1351 if (flags & O_NONBLOCK) { 1352 /* If we're not going to block, we schedule a timeout 1353 * function to generate a timeout on the connection 1354 * attempt, in case the peer doesn't respond in a 1355 * timely manner. We hold on to the socket until the 1356 * timeout fires. 1357 */ 1358 sock_hold(sk); 1359 schedule_delayed_work(&vsk->connect_work, timeout); 1360 1361 /* Skip ahead to preserve error code set above. */ 1362 goto out_wait; 1363 } 1364 1365 release_sock(sk); 1366 timeout = schedule_timeout(timeout); 1367 lock_sock(sk); 1368 1369 if (signal_pending(current)) { 1370 err = sock_intr_errno(timeout); 1371 sk->sk_state = TCP_CLOSE; 1372 sock->state = SS_UNCONNECTED; 1373 vsock_transport_cancel_pkt(vsk); 1374 goto out_wait; 1375 } else if (timeout == 0) { 1376 err = -ETIMEDOUT; 1377 sk->sk_state = TCP_CLOSE; 1378 sock->state = SS_UNCONNECTED; 1379 vsock_transport_cancel_pkt(vsk); 1380 goto out_wait; 1381 } 1382 1383 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1384 } 1385 1386 if (sk->sk_err) { 1387 err = -sk->sk_err; 1388 sk->sk_state = TCP_CLOSE; 1389 sock->state = SS_UNCONNECTED; 1390 } else { 1391 err = 0; 1392 } 1393 1394 out_wait: 1395 finish_wait(sk_sleep(sk), &wait); 1396 out: 1397 release_sock(sk); 1398 return err; 1399 } 1400 1401 static int vsock_accept(struct socket *sock, struct socket *newsock, int flags, 1402 bool kern) 1403 { 1404 struct sock *listener; 1405 int err; 1406 struct sock *connected; 1407 struct vsock_sock *vconnected; 1408 long timeout; 1409 DEFINE_WAIT(wait); 1410 1411 err = 0; 1412 listener = sock->sk; 1413 1414 lock_sock(listener); 1415 1416 if (sock->type != SOCK_STREAM) { 1417 err = -EOPNOTSUPP; 1418 goto out; 1419 } 1420 1421 if (listener->sk_state != TCP_LISTEN) { 1422 err = -EINVAL; 1423 goto out; 1424 } 1425 1426 /* Wait for children sockets to appear; these are the new sockets 1427 * created upon connection establishment. 1428 */ 1429 timeout = sock_rcvtimeo(listener, flags & O_NONBLOCK); 1430 prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE); 1431 1432 while ((connected = vsock_dequeue_accept(listener)) == NULL && 1433 listener->sk_err == 0) { 1434 release_sock(listener); 1435 timeout = schedule_timeout(timeout); 1436 finish_wait(sk_sleep(listener), &wait); 1437 lock_sock(listener); 1438 1439 if (signal_pending(current)) { 1440 err = sock_intr_errno(timeout); 1441 goto out; 1442 } else if (timeout == 0) { 1443 err = -EAGAIN; 1444 goto out; 1445 } 1446 1447 prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE); 1448 } 1449 finish_wait(sk_sleep(listener), &wait); 1450 1451 if (listener->sk_err) 1452 err = -listener->sk_err; 1453 1454 if (connected) { 1455 sk_acceptq_removed(listener); 1456 1457 lock_sock_nested(connected, SINGLE_DEPTH_NESTING); 1458 vconnected = vsock_sk(connected); 1459 1460 /* If the listener socket has received an error, then we should 1461 * reject this socket and return. Note that we simply mark the 1462 * socket rejected, drop our reference, and let the cleanup 1463 * function handle the cleanup; the fact that we found it in 1464 * the listener's accept queue guarantees that the cleanup 1465 * function hasn't run yet. 1466 */ 1467 if (err) { 1468 vconnected->rejected = true; 1469 } else { 1470 newsock->state = SS_CONNECTED; 1471 sock_graft(connected, newsock); 1472 } 1473 1474 release_sock(connected); 1475 sock_put(connected); 1476 } 1477 1478 out: 1479 release_sock(listener); 1480 return err; 1481 } 1482 1483 static int vsock_listen(struct socket *sock, int backlog) 1484 { 1485 int err; 1486 struct sock *sk; 1487 struct vsock_sock *vsk; 1488 1489 sk = sock->sk; 1490 1491 lock_sock(sk); 1492 1493 if (sock->type != SOCK_STREAM) { 1494 err = -EOPNOTSUPP; 1495 goto out; 1496 } 1497 1498 if (sock->state != SS_UNCONNECTED) { 1499 err = -EINVAL; 1500 goto out; 1501 } 1502 1503 vsk = vsock_sk(sk); 1504 1505 if (!vsock_addr_bound(&vsk->local_addr)) { 1506 err = -EINVAL; 1507 goto out; 1508 } 1509 1510 sk->sk_max_ack_backlog = backlog; 1511 sk->sk_state = TCP_LISTEN; 1512 1513 err = 0; 1514 1515 out: 1516 release_sock(sk); 1517 return err; 1518 } 1519 1520 static void vsock_update_buffer_size(struct vsock_sock *vsk, 1521 const struct vsock_transport *transport, 1522 u64 val) 1523 { 1524 if (val > vsk->buffer_max_size) 1525 val = vsk->buffer_max_size; 1526 1527 if (val < vsk->buffer_min_size) 1528 val = vsk->buffer_min_size; 1529 1530 if (val != vsk->buffer_size && 1531 transport && transport->notify_buffer_size) 1532 transport->notify_buffer_size(vsk, &val); 1533 1534 vsk->buffer_size = val; 1535 } 1536 1537 static int vsock_stream_setsockopt(struct socket *sock, 1538 int level, 1539 int optname, 1540 sockptr_t optval, 1541 unsigned int optlen) 1542 { 1543 int err; 1544 struct sock *sk; 1545 struct vsock_sock *vsk; 1546 const struct vsock_transport *transport; 1547 u64 val; 1548 1549 if (level != AF_VSOCK) 1550 return -ENOPROTOOPT; 1551 1552 #define COPY_IN(_v) \ 1553 do { \ 1554 if (optlen < sizeof(_v)) { \ 1555 err = -EINVAL; \ 1556 goto exit; \ 1557 } \ 1558 if (copy_from_sockptr(&_v, optval, sizeof(_v)) != 0) { \ 1559 err = -EFAULT; \ 1560 goto exit; \ 1561 } \ 1562 } while (0) 1563 1564 err = 0; 1565 sk = sock->sk; 1566 vsk = vsock_sk(sk); 1567 1568 lock_sock(sk); 1569 1570 transport = vsk->transport; 1571 1572 switch (optname) { 1573 case SO_VM_SOCKETS_BUFFER_SIZE: 1574 COPY_IN(val); 1575 vsock_update_buffer_size(vsk, transport, val); 1576 break; 1577 1578 case SO_VM_SOCKETS_BUFFER_MAX_SIZE: 1579 COPY_IN(val); 1580 vsk->buffer_max_size = val; 1581 vsock_update_buffer_size(vsk, transport, vsk->buffer_size); 1582 break; 1583 1584 case SO_VM_SOCKETS_BUFFER_MIN_SIZE: 1585 COPY_IN(val); 1586 vsk->buffer_min_size = val; 1587 vsock_update_buffer_size(vsk, transport, vsk->buffer_size); 1588 break; 1589 1590 case SO_VM_SOCKETS_CONNECT_TIMEOUT: { 1591 struct __kernel_old_timeval tv; 1592 COPY_IN(tv); 1593 if (tv.tv_sec >= 0 && tv.tv_usec < USEC_PER_SEC && 1594 tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)) { 1595 vsk->connect_timeout = tv.tv_sec * HZ + 1596 DIV_ROUND_UP(tv.tv_usec, (1000000 / HZ)); 1597 if (vsk->connect_timeout == 0) 1598 vsk->connect_timeout = 1599 VSOCK_DEFAULT_CONNECT_TIMEOUT; 1600 1601 } else { 1602 err = -ERANGE; 1603 } 1604 break; 1605 } 1606 1607 default: 1608 err = -ENOPROTOOPT; 1609 break; 1610 } 1611 1612 #undef COPY_IN 1613 1614 exit: 1615 release_sock(sk); 1616 return err; 1617 } 1618 1619 static int vsock_stream_getsockopt(struct socket *sock, 1620 int level, int optname, 1621 char __user *optval, 1622 int __user *optlen) 1623 { 1624 int err; 1625 int len; 1626 struct sock *sk; 1627 struct vsock_sock *vsk; 1628 u64 val; 1629 1630 if (level != AF_VSOCK) 1631 return -ENOPROTOOPT; 1632 1633 err = get_user(len, optlen); 1634 if (err != 0) 1635 return err; 1636 1637 #define COPY_OUT(_v) \ 1638 do { \ 1639 if (len < sizeof(_v)) \ 1640 return -EINVAL; \ 1641 \ 1642 len = sizeof(_v); \ 1643 if (copy_to_user(optval, &_v, len) != 0) \ 1644 return -EFAULT; \ 1645 \ 1646 } while (0) 1647 1648 err = 0; 1649 sk = sock->sk; 1650 vsk = vsock_sk(sk); 1651 1652 switch (optname) { 1653 case SO_VM_SOCKETS_BUFFER_SIZE: 1654 val = vsk->buffer_size; 1655 COPY_OUT(val); 1656 break; 1657 1658 case SO_VM_SOCKETS_BUFFER_MAX_SIZE: 1659 val = vsk->buffer_max_size; 1660 COPY_OUT(val); 1661 break; 1662 1663 case SO_VM_SOCKETS_BUFFER_MIN_SIZE: 1664 val = vsk->buffer_min_size; 1665 COPY_OUT(val); 1666 break; 1667 1668 case SO_VM_SOCKETS_CONNECT_TIMEOUT: { 1669 struct __kernel_old_timeval tv; 1670 tv.tv_sec = vsk->connect_timeout / HZ; 1671 tv.tv_usec = 1672 (vsk->connect_timeout - 1673 tv.tv_sec * HZ) * (1000000 / HZ); 1674 COPY_OUT(tv); 1675 break; 1676 } 1677 default: 1678 return -ENOPROTOOPT; 1679 } 1680 1681 err = put_user(len, optlen); 1682 if (err != 0) 1683 return -EFAULT; 1684 1685 #undef COPY_OUT 1686 1687 return 0; 1688 } 1689 1690 static int vsock_stream_sendmsg(struct socket *sock, struct msghdr *msg, 1691 size_t len) 1692 { 1693 struct sock *sk; 1694 struct vsock_sock *vsk; 1695 const struct vsock_transport *transport; 1696 ssize_t total_written; 1697 long timeout; 1698 int err; 1699 struct vsock_transport_send_notify_data send_data; 1700 DEFINE_WAIT_FUNC(wait, woken_wake_function); 1701 1702 sk = sock->sk; 1703 vsk = vsock_sk(sk); 1704 total_written = 0; 1705 err = 0; 1706 1707 if (msg->msg_flags & MSG_OOB) 1708 return -EOPNOTSUPP; 1709 1710 lock_sock(sk); 1711 1712 transport = vsk->transport; 1713 1714 /* Callers should not provide a destination with stream sockets. */ 1715 if (msg->msg_namelen) { 1716 err = sk->sk_state == TCP_ESTABLISHED ? -EISCONN : -EOPNOTSUPP; 1717 goto out; 1718 } 1719 1720 /* Send data only if both sides are not shutdown in the direction. */ 1721 if (sk->sk_shutdown & SEND_SHUTDOWN || 1722 vsk->peer_shutdown & RCV_SHUTDOWN) { 1723 err = -EPIPE; 1724 goto out; 1725 } 1726 1727 if (!transport || sk->sk_state != TCP_ESTABLISHED || 1728 !vsock_addr_bound(&vsk->local_addr)) { 1729 err = -ENOTCONN; 1730 goto out; 1731 } 1732 1733 if (!vsock_addr_bound(&vsk->remote_addr)) { 1734 err = -EDESTADDRREQ; 1735 goto out; 1736 } 1737 1738 /* Wait for room in the produce queue to enqueue our user's data. */ 1739 timeout = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT); 1740 1741 err = transport->notify_send_init(vsk, &send_data); 1742 if (err < 0) 1743 goto out; 1744 1745 while (total_written < len) { 1746 ssize_t written; 1747 1748 add_wait_queue(sk_sleep(sk), &wait); 1749 while (vsock_stream_has_space(vsk) == 0 && 1750 sk->sk_err == 0 && 1751 !(sk->sk_shutdown & SEND_SHUTDOWN) && 1752 !(vsk->peer_shutdown & RCV_SHUTDOWN)) { 1753 1754 /* Don't wait for non-blocking sockets. */ 1755 if (timeout == 0) { 1756 err = -EAGAIN; 1757 remove_wait_queue(sk_sleep(sk), &wait); 1758 goto out_err; 1759 } 1760 1761 err = transport->notify_send_pre_block(vsk, &send_data); 1762 if (err < 0) { 1763 remove_wait_queue(sk_sleep(sk), &wait); 1764 goto out_err; 1765 } 1766 1767 release_sock(sk); 1768 timeout = wait_woken(&wait, TASK_INTERRUPTIBLE, timeout); 1769 lock_sock(sk); 1770 if (signal_pending(current)) { 1771 err = sock_intr_errno(timeout); 1772 remove_wait_queue(sk_sleep(sk), &wait); 1773 goto out_err; 1774 } else if (timeout == 0) { 1775 err = -EAGAIN; 1776 remove_wait_queue(sk_sleep(sk), &wait); 1777 goto out_err; 1778 } 1779 } 1780 remove_wait_queue(sk_sleep(sk), &wait); 1781 1782 /* These checks occur both as part of and after the loop 1783 * conditional since we need to check before and after 1784 * sleeping. 1785 */ 1786 if (sk->sk_err) { 1787 err = -sk->sk_err; 1788 goto out_err; 1789 } else if ((sk->sk_shutdown & SEND_SHUTDOWN) || 1790 (vsk->peer_shutdown & RCV_SHUTDOWN)) { 1791 err = -EPIPE; 1792 goto out_err; 1793 } 1794 1795 err = transport->notify_send_pre_enqueue(vsk, &send_data); 1796 if (err < 0) 1797 goto out_err; 1798 1799 /* Note that enqueue will only write as many bytes as are free 1800 * in the produce queue, so we don't need to ensure len is 1801 * smaller than the queue size. It is the caller's 1802 * responsibility to check how many bytes we were able to send. 1803 */ 1804 1805 written = transport->stream_enqueue( 1806 vsk, msg, 1807 len - total_written); 1808 if (written < 0) { 1809 err = -ENOMEM; 1810 goto out_err; 1811 } 1812 1813 total_written += written; 1814 1815 err = transport->notify_send_post_enqueue( 1816 vsk, written, &send_data); 1817 if (err < 0) 1818 goto out_err; 1819 1820 } 1821 1822 out_err: 1823 if (total_written > 0) 1824 err = total_written; 1825 out: 1826 release_sock(sk); 1827 return err; 1828 } 1829 1830 1831 static int 1832 vsock_stream_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, 1833 int flags) 1834 { 1835 struct sock *sk; 1836 struct vsock_sock *vsk; 1837 const struct vsock_transport *transport; 1838 int err; 1839 size_t target; 1840 ssize_t copied; 1841 long timeout; 1842 struct vsock_transport_recv_notify_data recv_data; 1843 1844 DEFINE_WAIT(wait); 1845 1846 sk = sock->sk; 1847 vsk = vsock_sk(sk); 1848 err = 0; 1849 1850 lock_sock(sk); 1851 1852 transport = vsk->transport; 1853 1854 if (!transport || sk->sk_state != TCP_ESTABLISHED) { 1855 /* Recvmsg is supposed to return 0 if a peer performs an 1856 * orderly shutdown. Differentiate between that case and when a 1857 * peer has not connected or a local shutdown occured with the 1858 * SOCK_DONE flag. 1859 */ 1860 if (sock_flag(sk, SOCK_DONE)) 1861 err = 0; 1862 else 1863 err = -ENOTCONN; 1864 1865 goto out; 1866 } 1867 1868 if (flags & MSG_OOB) { 1869 err = -EOPNOTSUPP; 1870 goto out; 1871 } 1872 1873 /* We don't check peer_shutdown flag here since peer may actually shut 1874 * down, but there can be data in the queue that a local socket can 1875 * receive. 1876 */ 1877 if (sk->sk_shutdown & RCV_SHUTDOWN) { 1878 err = 0; 1879 goto out; 1880 } 1881 1882 /* It is valid on Linux to pass in a zero-length receive buffer. This 1883 * is not an error. We may as well bail out now. 1884 */ 1885 if (!len) { 1886 err = 0; 1887 goto out; 1888 } 1889 1890 /* We must not copy less than target bytes into the user's buffer 1891 * before returning successfully, so we wait for the consume queue to 1892 * have that much data to consume before dequeueing. Note that this 1893 * makes it impossible to handle cases where target is greater than the 1894 * queue size. 1895 */ 1896 target = sock_rcvlowat(sk, flags & MSG_WAITALL, len); 1897 if (target >= transport->stream_rcvhiwat(vsk)) { 1898 err = -ENOMEM; 1899 goto out; 1900 } 1901 timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); 1902 copied = 0; 1903 1904 err = transport->notify_recv_init(vsk, target, &recv_data); 1905 if (err < 0) 1906 goto out; 1907 1908 1909 while (1) { 1910 s64 ready; 1911 1912 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1913 ready = vsock_stream_has_data(vsk); 1914 1915 if (ready == 0) { 1916 if (sk->sk_err != 0 || 1917 (sk->sk_shutdown & RCV_SHUTDOWN) || 1918 (vsk->peer_shutdown & SEND_SHUTDOWN)) { 1919 finish_wait(sk_sleep(sk), &wait); 1920 break; 1921 } 1922 /* Don't wait for non-blocking sockets. */ 1923 if (timeout == 0) { 1924 err = -EAGAIN; 1925 finish_wait(sk_sleep(sk), &wait); 1926 break; 1927 } 1928 1929 err = transport->notify_recv_pre_block( 1930 vsk, target, &recv_data); 1931 if (err < 0) { 1932 finish_wait(sk_sleep(sk), &wait); 1933 break; 1934 } 1935 release_sock(sk); 1936 timeout = schedule_timeout(timeout); 1937 lock_sock(sk); 1938 1939 if (signal_pending(current)) { 1940 err = sock_intr_errno(timeout); 1941 finish_wait(sk_sleep(sk), &wait); 1942 break; 1943 } else if (timeout == 0) { 1944 err = -EAGAIN; 1945 finish_wait(sk_sleep(sk), &wait); 1946 break; 1947 } 1948 } else { 1949 ssize_t read; 1950 1951 finish_wait(sk_sleep(sk), &wait); 1952 1953 if (ready < 0) { 1954 /* Invalid queue pair content. XXX This should 1955 * be changed to a connection reset in a later 1956 * change. 1957 */ 1958 1959 err = -ENOMEM; 1960 goto out; 1961 } 1962 1963 err = transport->notify_recv_pre_dequeue( 1964 vsk, target, &recv_data); 1965 if (err < 0) 1966 break; 1967 1968 read = transport->stream_dequeue( 1969 vsk, msg, 1970 len - copied, flags); 1971 if (read < 0) { 1972 err = -ENOMEM; 1973 break; 1974 } 1975 1976 copied += read; 1977 1978 err = transport->notify_recv_post_dequeue( 1979 vsk, target, read, 1980 !(flags & MSG_PEEK), &recv_data); 1981 if (err < 0) 1982 goto out; 1983 1984 if (read >= target || flags & MSG_PEEK) 1985 break; 1986 1987 target -= read; 1988 } 1989 } 1990 1991 if (sk->sk_err) 1992 err = -sk->sk_err; 1993 else if (sk->sk_shutdown & RCV_SHUTDOWN) 1994 err = 0; 1995 1996 if (copied > 0) 1997 err = copied; 1998 1999 out: 2000 release_sock(sk); 2001 return err; 2002 } 2003 2004 static const struct proto_ops vsock_stream_ops = { 2005 .family = PF_VSOCK, 2006 .owner = THIS_MODULE, 2007 .release = vsock_release, 2008 .bind = vsock_bind, 2009 .connect = vsock_stream_connect, 2010 .socketpair = sock_no_socketpair, 2011 .accept = vsock_accept, 2012 .getname = vsock_getname, 2013 .poll = vsock_poll, 2014 .ioctl = sock_no_ioctl, 2015 .listen = vsock_listen, 2016 .shutdown = vsock_shutdown, 2017 .setsockopt = vsock_stream_setsockopt, 2018 .getsockopt = vsock_stream_getsockopt, 2019 .sendmsg = vsock_stream_sendmsg, 2020 .recvmsg = vsock_stream_recvmsg, 2021 .mmap = sock_no_mmap, 2022 .sendpage = sock_no_sendpage, 2023 }; 2024 2025 static int vsock_create(struct net *net, struct socket *sock, 2026 int protocol, int kern) 2027 { 2028 struct vsock_sock *vsk; 2029 struct sock *sk; 2030 int ret; 2031 2032 if (!sock) 2033 return -EINVAL; 2034 2035 if (protocol && protocol != PF_VSOCK) 2036 return -EPROTONOSUPPORT; 2037 2038 switch (sock->type) { 2039 case SOCK_DGRAM: 2040 sock->ops = &vsock_dgram_ops; 2041 break; 2042 case SOCK_STREAM: 2043 sock->ops = &vsock_stream_ops; 2044 break; 2045 default: 2046 return -ESOCKTNOSUPPORT; 2047 } 2048 2049 sock->state = SS_UNCONNECTED; 2050 2051 sk = __vsock_create(net, sock, NULL, GFP_KERNEL, 0, kern); 2052 if (!sk) 2053 return -ENOMEM; 2054 2055 vsk = vsock_sk(sk); 2056 2057 if (sock->type == SOCK_DGRAM) { 2058 ret = vsock_assign_transport(vsk, NULL); 2059 if (ret < 0) { 2060 sock_put(sk); 2061 return ret; 2062 } 2063 } 2064 2065 vsock_insert_unbound(vsk); 2066 2067 return 0; 2068 } 2069 2070 static const struct net_proto_family vsock_family_ops = { 2071 .family = AF_VSOCK, 2072 .create = vsock_create, 2073 .owner = THIS_MODULE, 2074 }; 2075 2076 static long vsock_dev_do_ioctl(struct file *filp, 2077 unsigned int cmd, void __user *ptr) 2078 { 2079 u32 __user *p = ptr; 2080 u32 cid = VMADDR_CID_ANY; 2081 int retval = 0; 2082 2083 switch (cmd) { 2084 case IOCTL_VM_SOCKETS_GET_LOCAL_CID: 2085 /* To be compatible with the VMCI behavior, we prioritize the 2086 * guest CID instead of well-know host CID (VMADDR_CID_HOST). 2087 */ 2088 if (transport_g2h) 2089 cid = transport_g2h->get_local_cid(); 2090 else if (transport_h2g) 2091 cid = transport_h2g->get_local_cid(); 2092 2093 if (put_user(cid, p) != 0) 2094 retval = -EFAULT; 2095 break; 2096 2097 default: 2098 retval = -ENOIOCTLCMD; 2099 } 2100 2101 return retval; 2102 } 2103 2104 static long vsock_dev_ioctl(struct file *filp, 2105 unsigned int cmd, unsigned long arg) 2106 { 2107 return vsock_dev_do_ioctl(filp, cmd, (void __user *)arg); 2108 } 2109 2110 #ifdef CONFIG_COMPAT 2111 static long vsock_dev_compat_ioctl(struct file *filp, 2112 unsigned int cmd, unsigned long arg) 2113 { 2114 return vsock_dev_do_ioctl(filp, cmd, compat_ptr(arg)); 2115 } 2116 #endif 2117 2118 static const struct file_operations vsock_device_ops = { 2119 .owner = THIS_MODULE, 2120 .unlocked_ioctl = vsock_dev_ioctl, 2121 #ifdef CONFIG_COMPAT 2122 .compat_ioctl = vsock_dev_compat_ioctl, 2123 #endif 2124 .open = nonseekable_open, 2125 }; 2126 2127 static struct miscdevice vsock_device = { 2128 .name = "vsock", 2129 .fops = &vsock_device_ops, 2130 }; 2131 2132 static int __init vsock_init(void) 2133 { 2134 int err = 0; 2135 2136 vsock_init_tables(); 2137 2138 vsock_proto.owner = THIS_MODULE; 2139 vsock_device.minor = MISC_DYNAMIC_MINOR; 2140 err = misc_register(&vsock_device); 2141 if (err) { 2142 pr_err("Failed to register misc device\n"); 2143 goto err_reset_transport; 2144 } 2145 2146 err = proto_register(&vsock_proto, 1); /* we want our slab */ 2147 if (err) { 2148 pr_err("Cannot register vsock protocol\n"); 2149 goto err_deregister_misc; 2150 } 2151 2152 err = sock_register(&vsock_family_ops); 2153 if (err) { 2154 pr_err("could not register af_vsock (%d) address family: %d\n", 2155 AF_VSOCK, err); 2156 goto err_unregister_proto; 2157 } 2158 2159 return 0; 2160 2161 err_unregister_proto: 2162 proto_unregister(&vsock_proto); 2163 err_deregister_misc: 2164 misc_deregister(&vsock_device); 2165 err_reset_transport: 2166 return err; 2167 } 2168 2169 static void __exit vsock_exit(void) 2170 { 2171 misc_deregister(&vsock_device); 2172 sock_unregister(AF_VSOCK); 2173 proto_unregister(&vsock_proto); 2174 } 2175 2176 const struct vsock_transport *vsock_core_get_transport(struct vsock_sock *vsk) 2177 { 2178 return vsk->transport; 2179 } 2180 EXPORT_SYMBOL_GPL(vsock_core_get_transport); 2181 2182 int vsock_core_register(const struct vsock_transport *t, int features) 2183 { 2184 const struct vsock_transport *t_h2g, *t_g2h, *t_dgram, *t_local; 2185 int err = mutex_lock_interruptible(&vsock_register_mutex); 2186 2187 if (err) 2188 return err; 2189 2190 t_h2g = transport_h2g; 2191 t_g2h = transport_g2h; 2192 t_dgram = transport_dgram; 2193 t_local = transport_local; 2194 2195 if (features & VSOCK_TRANSPORT_F_H2G) { 2196 if (t_h2g) { 2197 err = -EBUSY; 2198 goto err_busy; 2199 } 2200 t_h2g = t; 2201 } 2202 2203 if (features & VSOCK_TRANSPORT_F_G2H) { 2204 if (t_g2h) { 2205 err = -EBUSY; 2206 goto err_busy; 2207 } 2208 t_g2h = t; 2209 } 2210 2211 if (features & VSOCK_TRANSPORT_F_DGRAM) { 2212 if (t_dgram) { 2213 err = -EBUSY; 2214 goto err_busy; 2215 } 2216 t_dgram = t; 2217 } 2218 2219 if (features & VSOCK_TRANSPORT_F_LOCAL) { 2220 if (t_local) { 2221 err = -EBUSY; 2222 goto err_busy; 2223 } 2224 t_local = t; 2225 } 2226 2227 transport_h2g = t_h2g; 2228 transport_g2h = t_g2h; 2229 transport_dgram = t_dgram; 2230 transport_local = t_local; 2231 2232 err_busy: 2233 mutex_unlock(&vsock_register_mutex); 2234 return err; 2235 } 2236 EXPORT_SYMBOL_GPL(vsock_core_register); 2237 2238 void vsock_core_unregister(const struct vsock_transport *t) 2239 { 2240 mutex_lock(&vsock_register_mutex); 2241 2242 if (transport_h2g == t) 2243 transport_h2g = NULL; 2244 2245 if (transport_g2h == t) 2246 transport_g2h = NULL; 2247 2248 if (transport_dgram == t) 2249 transport_dgram = NULL; 2250 2251 if (transport_local == t) 2252 transport_local = NULL; 2253 2254 mutex_unlock(&vsock_register_mutex); 2255 } 2256 EXPORT_SYMBOL_GPL(vsock_core_unregister); 2257 2258 module_init(vsock_init); 2259 module_exit(vsock_exit); 2260 2261 MODULE_AUTHOR("VMware, Inc."); 2262 MODULE_DESCRIPTION("VMware Virtual Socket Family"); 2263 MODULE_VERSION("1.0.2.0-k"); 2264 MODULE_LICENSE("GPL v2"); 2265