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 static const struct vsock_transport *transport; 130 static DEFINE_MUTEX(vsock_register_mutex); 131 132 /**** EXPORTS ****/ 133 134 /* Get the ID of the local context. This is transport dependent. */ 135 136 int vm_sockets_get_local_cid(void) 137 { 138 return transport->get_local_cid(); 139 } 140 EXPORT_SYMBOL_GPL(vm_sockets_get_local_cid); 141 142 /**** UTILS ****/ 143 144 /* Each bound VSocket is stored in the bind hash table and each connected 145 * VSocket is stored in the connected hash table. 146 * 147 * Unbound sockets are all put on the same list attached to the end of the hash 148 * table (vsock_unbound_sockets). Bound sockets are added to the hash table in 149 * the bucket that their local address hashes to (vsock_bound_sockets(addr) 150 * represents the list that addr hashes to). 151 * 152 * Specifically, we initialize the vsock_bind_table array to a size of 153 * VSOCK_HASH_SIZE + 1 so that vsock_bind_table[0] through 154 * vsock_bind_table[VSOCK_HASH_SIZE - 1] are for bound sockets and 155 * vsock_bind_table[VSOCK_HASH_SIZE] is for unbound sockets. The hash function 156 * mods with VSOCK_HASH_SIZE to ensure this. 157 */ 158 #define MAX_PORT_RETRIES 24 159 160 #define VSOCK_HASH(addr) ((addr)->svm_port % VSOCK_HASH_SIZE) 161 #define vsock_bound_sockets(addr) (&vsock_bind_table[VSOCK_HASH(addr)]) 162 #define vsock_unbound_sockets (&vsock_bind_table[VSOCK_HASH_SIZE]) 163 164 /* XXX This can probably be implemented in a better way. */ 165 #define VSOCK_CONN_HASH(src, dst) \ 166 (((src)->svm_cid ^ (dst)->svm_port) % VSOCK_HASH_SIZE) 167 #define vsock_connected_sockets(src, dst) \ 168 (&vsock_connected_table[VSOCK_CONN_HASH(src, dst)]) 169 #define vsock_connected_sockets_vsk(vsk) \ 170 vsock_connected_sockets(&(vsk)->remote_addr, &(vsk)->local_addr) 171 172 struct list_head vsock_bind_table[VSOCK_HASH_SIZE + 1]; 173 EXPORT_SYMBOL_GPL(vsock_bind_table); 174 struct list_head vsock_connected_table[VSOCK_HASH_SIZE]; 175 EXPORT_SYMBOL_GPL(vsock_connected_table); 176 DEFINE_SPINLOCK(vsock_table_lock); 177 EXPORT_SYMBOL_GPL(vsock_table_lock); 178 179 /* Autobind this socket to the local address if necessary. */ 180 static int vsock_auto_bind(struct vsock_sock *vsk) 181 { 182 struct sock *sk = sk_vsock(vsk); 183 struct sockaddr_vm local_addr; 184 185 if (vsock_addr_bound(&vsk->local_addr)) 186 return 0; 187 vsock_addr_init(&local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 188 return __vsock_bind(sk, &local_addr); 189 } 190 191 static int __init vsock_init_tables(void) 192 { 193 int i; 194 195 for (i = 0; i < ARRAY_SIZE(vsock_bind_table); i++) 196 INIT_LIST_HEAD(&vsock_bind_table[i]); 197 198 for (i = 0; i < ARRAY_SIZE(vsock_connected_table); i++) 199 INIT_LIST_HEAD(&vsock_connected_table[i]); 200 return 0; 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 (addr->svm_port == vsk->local_addr.svm_port) 235 return sk_vsock(vsk); 236 237 return NULL; 238 } 239 240 static struct sock *__vsock_find_connected_socket(struct sockaddr_vm *src, 241 struct sockaddr_vm *dst) 242 { 243 struct vsock_sock *vsk; 244 245 list_for_each_entry(vsk, vsock_connected_sockets(src, dst), 246 connected_table) { 247 if (vsock_addr_equals_addr(src, &vsk->remote_addr) && 248 dst->svm_port == vsk->local_addr.svm_port) { 249 return sk_vsock(vsk); 250 } 251 } 252 253 return NULL; 254 } 255 256 static void vsock_insert_unbound(struct vsock_sock *vsk) 257 { 258 spin_lock_bh(&vsock_table_lock); 259 __vsock_insert_bound(vsock_unbound_sockets, vsk); 260 spin_unlock_bh(&vsock_table_lock); 261 } 262 263 void vsock_insert_connected(struct vsock_sock *vsk) 264 { 265 struct list_head *list = vsock_connected_sockets( 266 &vsk->remote_addr, &vsk->local_addr); 267 268 spin_lock_bh(&vsock_table_lock); 269 __vsock_insert_connected(list, vsk); 270 spin_unlock_bh(&vsock_table_lock); 271 } 272 EXPORT_SYMBOL_GPL(vsock_insert_connected); 273 274 void vsock_remove_bound(struct vsock_sock *vsk) 275 { 276 spin_lock_bh(&vsock_table_lock); 277 if (__vsock_in_bound_table(vsk)) 278 __vsock_remove_bound(vsk); 279 spin_unlock_bh(&vsock_table_lock); 280 } 281 EXPORT_SYMBOL_GPL(vsock_remove_bound); 282 283 void vsock_remove_connected(struct vsock_sock *vsk) 284 { 285 spin_lock_bh(&vsock_table_lock); 286 if (__vsock_in_connected_table(vsk)) 287 __vsock_remove_connected(vsk); 288 spin_unlock_bh(&vsock_table_lock); 289 } 290 EXPORT_SYMBOL_GPL(vsock_remove_connected); 291 292 struct sock *vsock_find_bound_socket(struct sockaddr_vm *addr) 293 { 294 struct sock *sk; 295 296 spin_lock_bh(&vsock_table_lock); 297 sk = __vsock_find_bound_socket(addr); 298 if (sk) 299 sock_hold(sk); 300 301 spin_unlock_bh(&vsock_table_lock); 302 303 return sk; 304 } 305 EXPORT_SYMBOL_GPL(vsock_find_bound_socket); 306 307 struct sock *vsock_find_connected_socket(struct sockaddr_vm *src, 308 struct sockaddr_vm *dst) 309 { 310 struct sock *sk; 311 312 spin_lock_bh(&vsock_table_lock); 313 sk = __vsock_find_connected_socket(src, dst); 314 if (sk) 315 sock_hold(sk); 316 317 spin_unlock_bh(&vsock_table_lock); 318 319 return sk; 320 } 321 EXPORT_SYMBOL_GPL(vsock_find_connected_socket); 322 323 void vsock_remove_sock(struct vsock_sock *vsk) 324 { 325 vsock_remove_bound(vsk); 326 vsock_remove_connected(vsk); 327 } 328 EXPORT_SYMBOL_GPL(vsock_remove_sock); 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 static 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, pending_work.work); 432 sk = sk_vsock(vsk); 433 listener = vsk->listener; 434 cleanup = true; 435 436 lock_sock(listener); 437 lock_sock_nested(sk, SINGLE_DEPTH_NESTING); 438 439 if (vsock_is_pending(sk)) { 440 vsock_remove_pending(listener, sk); 441 442 listener->sk_ack_backlog--; 443 } else if (!vsk->rejected) { 444 /* We are not on the pending list and accept() did not reject 445 * us, so we must have been accepted by our user process. We 446 * just need to drop our references to the sockets and be on 447 * our way. 448 */ 449 cleanup = false; 450 goto out; 451 } 452 453 /* 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 vsock_remove_connected(vsk); 458 459 sk->sk_state = TCP_CLOSE; 460 461 out: 462 release_sock(sk); 463 release_sock(listener); 464 if (cleanup) 465 sock_put(sk); 466 467 sock_put(sk); 468 sock_put(listener); 469 } 470 471 /**** SOCKET OPERATIONS ****/ 472 473 static int __vsock_bind_stream(struct vsock_sock *vsk, 474 struct sockaddr_vm *addr) 475 { 476 static u32 port; 477 struct sockaddr_vm new_addr; 478 479 if (!port) 480 port = LAST_RESERVED_PORT + 1 + 481 prandom_u32_max(U32_MAX - LAST_RESERVED_PORT); 482 483 vsock_addr_init(&new_addr, addr->svm_cid, addr->svm_port); 484 485 if (addr->svm_port == VMADDR_PORT_ANY) { 486 bool found = false; 487 unsigned int i; 488 489 for (i = 0; i < MAX_PORT_RETRIES; i++) { 490 if (port <= LAST_RESERVED_PORT) 491 port = LAST_RESERVED_PORT + 1; 492 493 new_addr.svm_port = port++; 494 495 if (!__vsock_find_bound_socket(&new_addr)) { 496 found = true; 497 break; 498 } 499 } 500 501 if (!found) 502 return -EADDRNOTAVAIL; 503 } else { 504 /* If port is in reserved range, ensure caller 505 * has necessary privileges. 506 */ 507 if (addr->svm_port <= LAST_RESERVED_PORT && 508 !capable(CAP_NET_BIND_SERVICE)) { 509 return -EACCES; 510 } 511 512 if (__vsock_find_bound_socket(&new_addr)) 513 return -EADDRINUSE; 514 } 515 516 vsock_addr_init(&vsk->local_addr, new_addr.svm_cid, new_addr.svm_port); 517 518 /* Remove stream sockets from the unbound list and add them to the hash 519 * table for easy lookup by its address. The unbound list is simply an 520 * extra entry at the end of the hash table, a trick used by AF_UNIX. 521 */ 522 __vsock_remove_bound(vsk); 523 __vsock_insert_bound(vsock_bound_sockets(&vsk->local_addr), vsk); 524 525 return 0; 526 } 527 528 static int __vsock_bind_dgram(struct vsock_sock *vsk, 529 struct sockaddr_vm *addr) 530 { 531 return transport->dgram_bind(vsk, addr); 532 } 533 534 static int __vsock_bind(struct sock *sk, struct sockaddr_vm *addr) 535 { 536 struct vsock_sock *vsk = vsock_sk(sk); 537 u32 cid; 538 int retval; 539 540 /* First ensure this socket isn't already bound. */ 541 if (vsock_addr_bound(&vsk->local_addr)) 542 return -EINVAL; 543 544 /* Now bind to the provided address or select appropriate values if 545 * none are provided (VMADDR_CID_ANY and VMADDR_PORT_ANY). Note that 546 * like AF_INET prevents binding to a non-local IP address (in most 547 * cases), we only allow binding to the local CID. 548 */ 549 cid = transport->get_local_cid(); 550 if (addr->svm_cid != cid && addr->svm_cid != VMADDR_CID_ANY) 551 return -EADDRNOTAVAIL; 552 553 switch (sk->sk_socket->type) { 554 case SOCK_STREAM: 555 spin_lock_bh(&vsock_table_lock); 556 retval = __vsock_bind_stream(vsk, addr); 557 spin_unlock_bh(&vsock_table_lock); 558 break; 559 560 case SOCK_DGRAM: 561 retval = __vsock_bind_dgram(vsk, addr); 562 break; 563 564 default: 565 retval = -EINVAL; 566 break; 567 } 568 569 return retval; 570 } 571 572 static void vsock_connect_timeout(struct work_struct *work); 573 574 struct sock *__vsock_create(struct net *net, 575 struct socket *sock, 576 struct sock *parent, 577 gfp_t priority, 578 unsigned short type, 579 int kern) 580 { 581 struct sock *sk; 582 struct vsock_sock *psk; 583 struct vsock_sock *vsk; 584 585 sk = sk_alloc(net, AF_VSOCK, priority, &vsock_proto, kern); 586 if (!sk) 587 return NULL; 588 589 sock_init_data(sock, sk); 590 591 /* sk->sk_type is normally set in sock_init_data, but only if sock is 592 * non-NULL. We make sure that our sockets always have a type by 593 * setting it here if needed. 594 */ 595 if (!sock) 596 sk->sk_type = type; 597 598 vsk = vsock_sk(sk); 599 vsock_addr_init(&vsk->local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 600 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 601 602 sk->sk_destruct = vsock_sk_destruct; 603 sk->sk_backlog_rcv = vsock_queue_rcv_skb; 604 sock_reset_flag(sk, SOCK_DONE); 605 606 INIT_LIST_HEAD(&vsk->bound_table); 607 INIT_LIST_HEAD(&vsk->connected_table); 608 vsk->listener = NULL; 609 INIT_LIST_HEAD(&vsk->pending_links); 610 INIT_LIST_HEAD(&vsk->accept_queue); 611 vsk->rejected = false; 612 vsk->sent_request = false; 613 vsk->ignore_connecting_rst = false; 614 vsk->peer_shutdown = 0; 615 INIT_DELAYED_WORK(&vsk->connect_work, vsock_connect_timeout); 616 INIT_DELAYED_WORK(&vsk->pending_work, vsock_pending_work); 617 618 psk = parent ? vsock_sk(parent) : NULL; 619 if (parent) { 620 vsk->trusted = psk->trusted; 621 vsk->owner = get_cred(psk->owner); 622 vsk->connect_timeout = psk->connect_timeout; 623 } else { 624 vsk->trusted = capable(CAP_NET_ADMIN); 625 vsk->owner = get_current_cred(); 626 vsk->connect_timeout = VSOCK_DEFAULT_CONNECT_TIMEOUT; 627 } 628 629 if (transport->init(vsk, psk) < 0) { 630 sk_free(sk); 631 return NULL; 632 } 633 634 if (sock) 635 vsock_insert_unbound(vsk); 636 637 return sk; 638 } 639 EXPORT_SYMBOL_GPL(__vsock_create); 640 641 static void __vsock_release(struct sock *sk, int level) 642 { 643 if (sk) { 644 struct sk_buff *skb; 645 struct sock *pending; 646 struct vsock_sock *vsk; 647 648 vsk = vsock_sk(sk); 649 pending = NULL; /* Compiler warning. */ 650 651 /* The release call is supposed to use lock_sock_nested() 652 * rather than lock_sock(), if a sock lock should be acquired. 653 */ 654 transport->release(vsk); 655 656 /* When "level" is SINGLE_DEPTH_NESTING, use the nested 657 * version to avoid the warning "possible recursive locking 658 * detected". When "level" is 0, lock_sock_nested(sk, level) 659 * is the same as lock_sock(sk). 660 */ 661 lock_sock_nested(sk, level); 662 sock_orphan(sk); 663 sk->sk_shutdown = SHUTDOWN_MASK; 664 665 while ((skb = skb_dequeue(&sk->sk_receive_queue))) 666 kfree_skb(skb); 667 668 /* Clean up any sockets that never were accepted. */ 669 while ((pending = vsock_dequeue_accept(sk)) != NULL) { 670 __vsock_release(pending, SINGLE_DEPTH_NESTING); 671 sock_put(pending); 672 } 673 674 release_sock(sk); 675 sock_put(sk); 676 } 677 } 678 679 static void vsock_sk_destruct(struct sock *sk) 680 { 681 struct vsock_sock *vsk = vsock_sk(sk); 682 683 transport->destruct(vsk); 684 685 /* When clearing these addresses, there's no need to set the family and 686 * possibly register the address family with the kernel. 687 */ 688 vsock_addr_init(&vsk->local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 689 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 690 691 put_cred(vsk->owner); 692 } 693 694 static int vsock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 695 { 696 int err; 697 698 err = sock_queue_rcv_skb(sk, skb); 699 if (err) 700 kfree_skb(skb); 701 702 return err; 703 } 704 705 s64 vsock_stream_has_data(struct vsock_sock *vsk) 706 { 707 return transport->stream_has_data(vsk); 708 } 709 EXPORT_SYMBOL_GPL(vsock_stream_has_data); 710 711 s64 vsock_stream_has_space(struct vsock_sock *vsk) 712 { 713 return transport->stream_has_space(vsk); 714 } 715 EXPORT_SYMBOL_GPL(vsock_stream_has_space); 716 717 static int vsock_release(struct socket *sock) 718 { 719 __vsock_release(sock->sk, 0); 720 sock->sk = NULL; 721 sock->state = SS_FREE; 722 723 return 0; 724 } 725 726 static int 727 vsock_bind(struct socket *sock, struct sockaddr *addr, int addr_len) 728 { 729 int err; 730 struct sock *sk; 731 struct sockaddr_vm *vm_addr; 732 733 sk = sock->sk; 734 735 if (vsock_addr_cast(addr, addr_len, &vm_addr) != 0) 736 return -EINVAL; 737 738 lock_sock(sk); 739 err = __vsock_bind(sk, vm_addr); 740 release_sock(sk); 741 742 return err; 743 } 744 745 static int vsock_getname(struct socket *sock, 746 struct sockaddr *addr, int peer) 747 { 748 int err; 749 struct sock *sk; 750 struct vsock_sock *vsk; 751 struct sockaddr_vm *vm_addr; 752 753 sk = sock->sk; 754 vsk = vsock_sk(sk); 755 err = 0; 756 757 lock_sock(sk); 758 759 if (peer) { 760 if (sock->state != SS_CONNECTED) { 761 err = -ENOTCONN; 762 goto out; 763 } 764 vm_addr = &vsk->remote_addr; 765 } else { 766 vm_addr = &vsk->local_addr; 767 } 768 769 if (!vm_addr) { 770 err = -EINVAL; 771 goto out; 772 } 773 774 /* sys_getsockname() and sys_getpeername() pass us a 775 * MAX_SOCK_ADDR-sized buffer and don't set addr_len. Unfortunately 776 * that macro is defined in socket.c instead of .h, so we hardcode its 777 * value here. 778 */ 779 BUILD_BUG_ON(sizeof(*vm_addr) > 128); 780 memcpy(addr, vm_addr, sizeof(*vm_addr)); 781 err = sizeof(*vm_addr); 782 783 out: 784 release_sock(sk); 785 return err; 786 } 787 788 static int vsock_shutdown(struct socket *sock, int mode) 789 { 790 int err; 791 struct sock *sk; 792 793 /* User level uses SHUT_RD (0) and SHUT_WR (1), but the kernel uses 794 * RCV_SHUTDOWN (1) and SEND_SHUTDOWN (2), so we must increment mode 795 * here like the other address families do. Note also that the 796 * increment makes SHUT_RDWR (2) into RCV_SHUTDOWN | SEND_SHUTDOWN (3), 797 * which is what we want. 798 */ 799 mode++; 800 801 if ((mode & ~SHUTDOWN_MASK) || !mode) 802 return -EINVAL; 803 804 /* If this is a STREAM socket and it is not connected then bail out 805 * immediately. If it is a DGRAM socket then we must first kick the 806 * socket so that it wakes up from any sleeping calls, for example 807 * recv(), and then afterwards return the error. 808 */ 809 810 sk = sock->sk; 811 if (sock->state == SS_UNCONNECTED) { 812 err = -ENOTCONN; 813 if (sk->sk_type == SOCK_STREAM) 814 return err; 815 } else { 816 sock->state = SS_DISCONNECTING; 817 err = 0; 818 } 819 820 /* Receive and send shutdowns are treated alike. */ 821 mode = mode & (RCV_SHUTDOWN | SEND_SHUTDOWN); 822 if (mode) { 823 lock_sock(sk); 824 sk->sk_shutdown |= mode; 825 sk->sk_state_change(sk); 826 release_sock(sk); 827 828 if (sk->sk_type == SOCK_STREAM) { 829 sock_reset_flag(sk, SOCK_DONE); 830 vsock_send_shutdown(sk, mode); 831 } 832 } 833 834 return err; 835 } 836 837 static __poll_t vsock_poll(struct file *file, struct socket *sock, 838 poll_table *wait) 839 { 840 struct sock *sk; 841 __poll_t mask; 842 struct vsock_sock *vsk; 843 844 sk = sock->sk; 845 vsk = vsock_sk(sk); 846 847 poll_wait(file, sk_sleep(sk), wait); 848 mask = 0; 849 850 if (sk->sk_err) 851 /* Signify that there has been an error on this socket. */ 852 mask |= EPOLLERR; 853 854 /* INET sockets treat local write shutdown and peer write shutdown as a 855 * case of EPOLLHUP set. 856 */ 857 if ((sk->sk_shutdown == SHUTDOWN_MASK) || 858 ((sk->sk_shutdown & SEND_SHUTDOWN) && 859 (vsk->peer_shutdown & SEND_SHUTDOWN))) { 860 mask |= EPOLLHUP; 861 } 862 863 if (sk->sk_shutdown & RCV_SHUTDOWN || 864 vsk->peer_shutdown & SEND_SHUTDOWN) { 865 mask |= EPOLLRDHUP; 866 } 867 868 if (sock->type == SOCK_DGRAM) { 869 /* For datagram sockets we can read if there is something in 870 * the queue and write as long as the socket isn't shutdown for 871 * sending. 872 */ 873 if (!skb_queue_empty_lockless(&sk->sk_receive_queue) || 874 (sk->sk_shutdown & RCV_SHUTDOWN)) { 875 mask |= EPOLLIN | EPOLLRDNORM; 876 } 877 878 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) 879 mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND; 880 881 } else if (sock->type == SOCK_STREAM) { 882 lock_sock(sk); 883 884 /* Listening sockets that have connections in their accept 885 * queue can be read. 886 */ 887 if (sk->sk_state == TCP_LISTEN 888 && !vsock_is_accept_queue_empty(sk)) 889 mask |= EPOLLIN | EPOLLRDNORM; 890 891 /* If there is something in the queue then we can read. */ 892 if (transport->stream_is_active(vsk) && 893 !(sk->sk_shutdown & RCV_SHUTDOWN)) { 894 bool data_ready_now = false; 895 int ret = transport->notify_poll_in( 896 vsk, 1, &data_ready_now); 897 if (ret < 0) { 898 mask |= EPOLLERR; 899 } else { 900 if (data_ready_now) 901 mask |= EPOLLIN | EPOLLRDNORM; 902 903 } 904 } 905 906 /* Sockets whose connections have been closed, reset, or 907 * terminated should also be considered read, and we check the 908 * shutdown flag for that. 909 */ 910 if (sk->sk_shutdown & RCV_SHUTDOWN || 911 vsk->peer_shutdown & SEND_SHUTDOWN) { 912 mask |= EPOLLIN | EPOLLRDNORM; 913 } 914 915 /* Connected sockets that can produce data can be written. */ 916 if (sk->sk_state == TCP_ESTABLISHED) { 917 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) { 918 bool space_avail_now = false; 919 int ret = transport->notify_poll_out( 920 vsk, 1, &space_avail_now); 921 if (ret < 0) { 922 mask |= EPOLLERR; 923 } else { 924 if (space_avail_now) 925 /* Remove EPOLLWRBAND since INET 926 * sockets are not setting it. 927 */ 928 mask |= EPOLLOUT | EPOLLWRNORM; 929 930 } 931 } 932 } 933 934 /* Simulate INET socket poll behaviors, which sets 935 * EPOLLOUT|EPOLLWRNORM when peer is closed and nothing to read, 936 * but local send is not shutdown. 937 */ 938 if (sk->sk_state == TCP_CLOSE || sk->sk_state == TCP_CLOSING) { 939 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) 940 mask |= EPOLLOUT | EPOLLWRNORM; 941 942 } 943 944 release_sock(sk); 945 } 946 947 return mask; 948 } 949 950 static int vsock_dgram_sendmsg(struct socket *sock, struct msghdr *msg, 951 size_t len) 952 { 953 int err; 954 struct sock *sk; 955 struct vsock_sock *vsk; 956 struct sockaddr_vm *remote_addr; 957 958 if (msg->msg_flags & MSG_OOB) 959 return -EOPNOTSUPP; 960 961 /* For now, MSG_DONTWAIT is always assumed... */ 962 err = 0; 963 sk = sock->sk; 964 vsk = vsock_sk(sk); 965 966 lock_sock(sk); 967 968 err = vsock_auto_bind(vsk); 969 if (err) 970 goto out; 971 972 973 /* If the provided message contains an address, use that. Otherwise 974 * fall back on the socket's remote handle (if it has been connected). 975 */ 976 if (msg->msg_name && 977 vsock_addr_cast(msg->msg_name, msg->msg_namelen, 978 &remote_addr) == 0) { 979 /* Ensure this address is of the right type and is a valid 980 * destination. 981 */ 982 983 if (remote_addr->svm_cid == VMADDR_CID_ANY) 984 remote_addr->svm_cid = transport->get_local_cid(); 985 986 if (!vsock_addr_bound(remote_addr)) { 987 err = -EINVAL; 988 goto out; 989 } 990 } else if (sock->state == SS_CONNECTED) { 991 remote_addr = &vsk->remote_addr; 992 993 if (remote_addr->svm_cid == VMADDR_CID_ANY) 994 remote_addr->svm_cid = transport->get_local_cid(); 995 996 /* XXX Should connect() or this function ensure remote_addr is 997 * bound? 998 */ 999 if (!vsock_addr_bound(&vsk->remote_addr)) { 1000 err = -EINVAL; 1001 goto out; 1002 } 1003 } else { 1004 err = -EINVAL; 1005 goto out; 1006 } 1007 1008 if (!transport->dgram_allow(remote_addr->svm_cid, 1009 remote_addr->svm_port)) { 1010 err = -EINVAL; 1011 goto out; 1012 } 1013 1014 err = transport->dgram_enqueue(vsk, remote_addr, msg, len); 1015 1016 out: 1017 release_sock(sk); 1018 return err; 1019 } 1020 1021 static int vsock_dgram_connect(struct socket *sock, 1022 struct sockaddr *addr, int addr_len, int flags) 1023 { 1024 int err; 1025 struct sock *sk; 1026 struct vsock_sock *vsk; 1027 struct sockaddr_vm *remote_addr; 1028 1029 sk = sock->sk; 1030 vsk = vsock_sk(sk); 1031 1032 err = vsock_addr_cast(addr, addr_len, &remote_addr); 1033 if (err == -EAFNOSUPPORT && remote_addr->svm_family == AF_UNSPEC) { 1034 lock_sock(sk); 1035 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, 1036 VMADDR_PORT_ANY); 1037 sock->state = SS_UNCONNECTED; 1038 release_sock(sk); 1039 return 0; 1040 } else if (err != 0) 1041 return -EINVAL; 1042 1043 lock_sock(sk); 1044 1045 err = vsock_auto_bind(vsk); 1046 if (err) 1047 goto out; 1048 1049 if (!transport->dgram_allow(remote_addr->svm_cid, 1050 remote_addr->svm_port)) { 1051 err = -EINVAL; 1052 goto out; 1053 } 1054 1055 memcpy(&vsk->remote_addr, remote_addr, sizeof(vsk->remote_addr)); 1056 sock->state = SS_CONNECTED; 1057 1058 out: 1059 release_sock(sk); 1060 return err; 1061 } 1062 1063 static int vsock_dgram_recvmsg(struct socket *sock, struct msghdr *msg, 1064 size_t len, int flags) 1065 { 1066 return transport->dgram_dequeue(vsock_sk(sock->sk), msg, len, flags); 1067 } 1068 1069 static const struct proto_ops vsock_dgram_ops = { 1070 .family = PF_VSOCK, 1071 .owner = THIS_MODULE, 1072 .release = vsock_release, 1073 .bind = vsock_bind, 1074 .connect = vsock_dgram_connect, 1075 .socketpair = sock_no_socketpair, 1076 .accept = sock_no_accept, 1077 .getname = vsock_getname, 1078 .poll = vsock_poll, 1079 .ioctl = sock_no_ioctl, 1080 .listen = sock_no_listen, 1081 .shutdown = vsock_shutdown, 1082 .setsockopt = sock_no_setsockopt, 1083 .getsockopt = sock_no_getsockopt, 1084 .sendmsg = vsock_dgram_sendmsg, 1085 .recvmsg = vsock_dgram_recvmsg, 1086 .mmap = sock_no_mmap, 1087 .sendpage = sock_no_sendpage, 1088 }; 1089 1090 static int vsock_transport_cancel_pkt(struct vsock_sock *vsk) 1091 { 1092 if (!transport->cancel_pkt) 1093 return -EOPNOTSUPP; 1094 1095 return transport->cancel_pkt(vsk); 1096 } 1097 1098 static void vsock_connect_timeout(struct work_struct *work) 1099 { 1100 struct sock *sk; 1101 struct vsock_sock *vsk; 1102 int cancel = 0; 1103 1104 vsk = container_of(work, struct vsock_sock, connect_work.work); 1105 sk = sk_vsock(vsk); 1106 1107 lock_sock(sk); 1108 if (sk->sk_state == TCP_SYN_SENT && 1109 (sk->sk_shutdown != SHUTDOWN_MASK)) { 1110 sk->sk_state = TCP_CLOSE; 1111 sk->sk_err = ETIMEDOUT; 1112 sk->sk_error_report(sk); 1113 cancel = 1; 1114 } 1115 release_sock(sk); 1116 if (cancel) 1117 vsock_transport_cancel_pkt(vsk); 1118 1119 sock_put(sk); 1120 } 1121 1122 static int vsock_stream_connect(struct socket *sock, struct sockaddr *addr, 1123 int addr_len, int flags) 1124 { 1125 int err; 1126 struct sock *sk; 1127 struct vsock_sock *vsk; 1128 struct sockaddr_vm *remote_addr; 1129 long timeout; 1130 DEFINE_WAIT(wait); 1131 1132 err = 0; 1133 sk = sock->sk; 1134 vsk = vsock_sk(sk); 1135 1136 lock_sock(sk); 1137 1138 /* XXX AF_UNSPEC should make us disconnect like AF_INET. */ 1139 switch (sock->state) { 1140 case SS_CONNECTED: 1141 err = -EISCONN; 1142 goto out; 1143 case SS_DISCONNECTING: 1144 err = -EINVAL; 1145 goto out; 1146 case SS_CONNECTING: 1147 /* This continues on so we can move sock into the SS_CONNECTED 1148 * state once the connection has completed (at which point err 1149 * will be set to zero also). Otherwise, we will either wait 1150 * for the connection or return -EALREADY should this be a 1151 * non-blocking call. 1152 */ 1153 err = -EALREADY; 1154 break; 1155 default: 1156 if ((sk->sk_state == TCP_LISTEN) || 1157 vsock_addr_cast(addr, addr_len, &remote_addr) != 0) { 1158 err = -EINVAL; 1159 goto out; 1160 } 1161 1162 /* The hypervisor and well-known contexts do not have socket 1163 * endpoints. 1164 */ 1165 if (!transport->stream_allow(remote_addr->svm_cid, 1166 remote_addr->svm_port)) { 1167 err = -ENETUNREACH; 1168 goto out; 1169 } 1170 1171 /* Set the remote address that we are connecting to. */ 1172 memcpy(&vsk->remote_addr, remote_addr, 1173 sizeof(vsk->remote_addr)); 1174 1175 err = vsock_auto_bind(vsk); 1176 if (err) 1177 goto out; 1178 1179 sk->sk_state = TCP_SYN_SENT; 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 != TCP_ESTABLISHED && 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 schedule_delayed_work(&vsk->connect_work, timeout); 1209 1210 /* Skip ahead to preserve error code set above. */ 1211 goto out_wait; 1212 } 1213 1214 release_sock(sk); 1215 timeout = schedule_timeout(timeout); 1216 lock_sock(sk); 1217 1218 if (signal_pending(current)) { 1219 err = sock_intr_errno(timeout); 1220 sk->sk_state = TCP_CLOSE; 1221 sock->state = SS_UNCONNECTED; 1222 vsock_transport_cancel_pkt(vsk); 1223 goto out_wait; 1224 } else if (timeout == 0) { 1225 err = -ETIMEDOUT; 1226 sk->sk_state = TCP_CLOSE; 1227 sock->state = SS_UNCONNECTED; 1228 vsock_transport_cancel_pkt(vsk); 1229 goto out_wait; 1230 } 1231 1232 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1233 } 1234 1235 if (sk->sk_err) { 1236 err = -sk->sk_err; 1237 sk->sk_state = TCP_CLOSE; 1238 sock->state = SS_UNCONNECTED; 1239 } else { 1240 err = 0; 1241 } 1242 1243 out_wait: 1244 finish_wait(sk_sleep(sk), &wait); 1245 out: 1246 release_sock(sk); 1247 return err; 1248 } 1249 1250 static int vsock_accept(struct socket *sock, struct socket *newsock, int flags, 1251 bool kern) 1252 { 1253 struct sock *listener; 1254 int err; 1255 struct sock *connected; 1256 struct vsock_sock *vconnected; 1257 long timeout; 1258 DEFINE_WAIT(wait); 1259 1260 err = 0; 1261 listener = sock->sk; 1262 1263 lock_sock(listener); 1264 1265 if (sock->type != SOCK_STREAM) { 1266 err = -EOPNOTSUPP; 1267 goto out; 1268 } 1269 1270 if (listener->sk_state != TCP_LISTEN) { 1271 err = -EINVAL; 1272 goto out; 1273 } 1274 1275 /* Wait for children sockets to appear; these are the new sockets 1276 * created upon connection establishment. 1277 */ 1278 timeout = sock_sndtimeo(listener, flags & O_NONBLOCK); 1279 prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE); 1280 1281 while ((connected = vsock_dequeue_accept(listener)) == NULL && 1282 listener->sk_err == 0) { 1283 release_sock(listener); 1284 timeout = schedule_timeout(timeout); 1285 finish_wait(sk_sleep(listener), &wait); 1286 lock_sock(listener); 1287 1288 if (signal_pending(current)) { 1289 err = sock_intr_errno(timeout); 1290 goto out; 1291 } else if (timeout == 0) { 1292 err = -EAGAIN; 1293 goto out; 1294 } 1295 1296 prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE); 1297 } 1298 finish_wait(sk_sleep(listener), &wait); 1299 1300 if (listener->sk_err) 1301 err = -listener->sk_err; 1302 1303 if (connected) { 1304 listener->sk_ack_backlog--; 1305 1306 lock_sock_nested(connected, SINGLE_DEPTH_NESTING); 1307 vconnected = vsock_sk(connected); 1308 1309 /* If the listener socket has received an error, then we should 1310 * reject this socket and return. Note that we simply mark the 1311 * socket rejected, drop our reference, and let the cleanup 1312 * function handle the cleanup; the fact that we found it in 1313 * the listener's accept queue guarantees that the cleanup 1314 * function hasn't run yet. 1315 */ 1316 if (err) { 1317 vconnected->rejected = true; 1318 } else { 1319 newsock->state = SS_CONNECTED; 1320 sock_graft(connected, newsock); 1321 } 1322 1323 release_sock(connected); 1324 sock_put(connected); 1325 } 1326 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 = TCP_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 __kernel_old_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 __kernel_old_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 socket *sock, struct msghdr *msg, 1518 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 DEFINE_WAIT_FUNC(wait, woken_wake_function); 1527 1528 sk = sock->sk; 1529 vsk = vsock_sk(sk); 1530 total_written = 0; 1531 err = 0; 1532 1533 if (msg->msg_flags & MSG_OOB) 1534 return -EOPNOTSUPP; 1535 1536 lock_sock(sk); 1537 1538 /* Callers should not provide a destination with stream sockets. */ 1539 if (msg->msg_namelen) { 1540 err = sk->sk_state == TCP_ESTABLISHED ? -EISCONN : -EOPNOTSUPP; 1541 goto out; 1542 } 1543 1544 /* Send data only if both sides are not shutdown in the direction. */ 1545 if (sk->sk_shutdown & SEND_SHUTDOWN || 1546 vsk->peer_shutdown & RCV_SHUTDOWN) { 1547 err = -EPIPE; 1548 goto out; 1549 } 1550 1551 if (sk->sk_state != TCP_ESTABLISHED || 1552 !vsock_addr_bound(&vsk->local_addr)) { 1553 err = -ENOTCONN; 1554 goto out; 1555 } 1556 1557 if (!vsock_addr_bound(&vsk->remote_addr)) { 1558 err = -EDESTADDRREQ; 1559 goto out; 1560 } 1561 1562 /* Wait for room in the produce queue to enqueue our user's data. */ 1563 timeout = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT); 1564 1565 err = transport->notify_send_init(vsk, &send_data); 1566 if (err < 0) 1567 goto out; 1568 1569 while (total_written < len) { 1570 ssize_t written; 1571 1572 add_wait_queue(sk_sleep(sk), &wait); 1573 while (vsock_stream_has_space(vsk) == 0 && 1574 sk->sk_err == 0 && 1575 !(sk->sk_shutdown & SEND_SHUTDOWN) && 1576 !(vsk->peer_shutdown & RCV_SHUTDOWN)) { 1577 1578 /* Don't wait for non-blocking sockets. */ 1579 if (timeout == 0) { 1580 err = -EAGAIN; 1581 remove_wait_queue(sk_sleep(sk), &wait); 1582 goto out_err; 1583 } 1584 1585 err = transport->notify_send_pre_block(vsk, &send_data); 1586 if (err < 0) { 1587 remove_wait_queue(sk_sleep(sk), &wait); 1588 goto out_err; 1589 } 1590 1591 release_sock(sk); 1592 timeout = wait_woken(&wait, TASK_INTERRUPTIBLE, timeout); 1593 lock_sock(sk); 1594 if (signal_pending(current)) { 1595 err = sock_intr_errno(timeout); 1596 remove_wait_queue(sk_sleep(sk), &wait); 1597 goto out_err; 1598 } else if (timeout == 0) { 1599 err = -EAGAIN; 1600 remove_wait_queue(sk_sleep(sk), &wait); 1601 goto out_err; 1602 } 1603 } 1604 remove_wait_queue(sk_sleep(sk), &wait); 1605 1606 /* These checks occur both as part of and after the loop 1607 * conditional since we need to check before and after 1608 * sleeping. 1609 */ 1610 if (sk->sk_err) { 1611 err = -sk->sk_err; 1612 goto out_err; 1613 } else if ((sk->sk_shutdown & SEND_SHUTDOWN) || 1614 (vsk->peer_shutdown & RCV_SHUTDOWN)) { 1615 err = -EPIPE; 1616 goto out_err; 1617 } 1618 1619 err = transport->notify_send_pre_enqueue(vsk, &send_data); 1620 if (err < 0) 1621 goto out_err; 1622 1623 /* Note that enqueue will only write as many bytes as are free 1624 * in the produce queue, so we don't need to ensure len is 1625 * smaller than the queue size. It is the caller's 1626 * responsibility to check how many bytes we were able to send. 1627 */ 1628 1629 written = transport->stream_enqueue( 1630 vsk, msg, 1631 len - total_written); 1632 if (written < 0) { 1633 err = -ENOMEM; 1634 goto out_err; 1635 } 1636 1637 total_written += written; 1638 1639 err = transport->notify_send_post_enqueue( 1640 vsk, written, &send_data); 1641 if (err < 0) 1642 goto out_err; 1643 1644 } 1645 1646 out_err: 1647 if (total_written > 0) 1648 err = total_written; 1649 out: 1650 release_sock(sk); 1651 return err; 1652 } 1653 1654 1655 static int 1656 vsock_stream_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, 1657 int flags) 1658 { 1659 struct sock *sk; 1660 struct vsock_sock *vsk; 1661 int err; 1662 size_t target; 1663 ssize_t copied; 1664 long timeout; 1665 struct vsock_transport_recv_notify_data recv_data; 1666 1667 DEFINE_WAIT(wait); 1668 1669 sk = sock->sk; 1670 vsk = vsock_sk(sk); 1671 err = 0; 1672 1673 lock_sock(sk); 1674 1675 if (sk->sk_state != TCP_ESTABLISHED) { 1676 /* Recvmsg is supposed to return 0 if a peer performs an 1677 * orderly shutdown. Differentiate between that case and when a 1678 * peer has not connected or a local shutdown occured with the 1679 * SOCK_DONE flag. 1680 */ 1681 if (sock_flag(sk, SOCK_DONE)) 1682 err = 0; 1683 else 1684 err = -ENOTCONN; 1685 1686 goto out; 1687 } 1688 1689 if (flags & MSG_OOB) { 1690 err = -EOPNOTSUPP; 1691 goto out; 1692 } 1693 1694 /* We don't check peer_shutdown flag here since peer may actually shut 1695 * down, but there can be data in the queue that a local socket can 1696 * receive. 1697 */ 1698 if (sk->sk_shutdown & RCV_SHUTDOWN) { 1699 err = 0; 1700 goto out; 1701 } 1702 1703 /* It is valid on Linux to pass in a zero-length receive buffer. This 1704 * is not an error. We may as well bail out now. 1705 */ 1706 if (!len) { 1707 err = 0; 1708 goto out; 1709 } 1710 1711 /* We must not copy less than target bytes into the user's buffer 1712 * before returning successfully, so we wait for the consume queue to 1713 * have that much data to consume before dequeueing. Note that this 1714 * makes it impossible to handle cases where target is greater than the 1715 * queue size. 1716 */ 1717 target = sock_rcvlowat(sk, flags & MSG_WAITALL, len); 1718 if (target >= transport->stream_rcvhiwat(vsk)) { 1719 err = -ENOMEM; 1720 goto out; 1721 } 1722 timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); 1723 copied = 0; 1724 1725 err = transport->notify_recv_init(vsk, target, &recv_data); 1726 if (err < 0) 1727 goto out; 1728 1729 1730 while (1) { 1731 s64 ready; 1732 1733 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1734 ready = vsock_stream_has_data(vsk); 1735 1736 if (ready == 0) { 1737 if (sk->sk_err != 0 || 1738 (sk->sk_shutdown & RCV_SHUTDOWN) || 1739 (vsk->peer_shutdown & SEND_SHUTDOWN)) { 1740 finish_wait(sk_sleep(sk), &wait); 1741 break; 1742 } 1743 /* Don't wait for non-blocking sockets. */ 1744 if (timeout == 0) { 1745 err = -EAGAIN; 1746 finish_wait(sk_sleep(sk), &wait); 1747 break; 1748 } 1749 1750 err = transport->notify_recv_pre_block( 1751 vsk, target, &recv_data); 1752 if (err < 0) { 1753 finish_wait(sk_sleep(sk), &wait); 1754 break; 1755 } 1756 release_sock(sk); 1757 timeout = schedule_timeout(timeout); 1758 lock_sock(sk); 1759 1760 if (signal_pending(current)) { 1761 err = sock_intr_errno(timeout); 1762 finish_wait(sk_sleep(sk), &wait); 1763 break; 1764 } else if (timeout == 0) { 1765 err = -EAGAIN; 1766 finish_wait(sk_sleep(sk), &wait); 1767 break; 1768 } 1769 } else { 1770 ssize_t read; 1771 1772 finish_wait(sk_sleep(sk), &wait); 1773 1774 if (ready < 0) { 1775 /* Invalid queue pair content. XXX This should 1776 * be changed to a connection reset in a later 1777 * change. 1778 */ 1779 1780 err = -ENOMEM; 1781 goto out; 1782 } 1783 1784 err = transport->notify_recv_pre_dequeue( 1785 vsk, target, &recv_data); 1786 if (err < 0) 1787 break; 1788 1789 read = transport->stream_dequeue( 1790 vsk, msg, 1791 len - copied, flags); 1792 if (read < 0) { 1793 err = -ENOMEM; 1794 break; 1795 } 1796 1797 copied += read; 1798 1799 err = transport->notify_recv_post_dequeue( 1800 vsk, target, read, 1801 !(flags & MSG_PEEK), &recv_data); 1802 if (err < 0) 1803 goto out; 1804 1805 if (read >= target || flags & MSG_PEEK) 1806 break; 1807 1808 target -= read; 1809 } 1810 } 1811 1812 if (sk->sk_err) 1813 err = -sk->sk_err; 1814 else if (sk->sk_shutdown & RCV_SHUTDOWN) 1815 err = 0; 1816 1817 if (copied > 0) 1818 err = copied; 1819 1820 out: 1821 release_sock(sk); 1822 return err; 1823 } 1824 1825 static const struct proto_ops vsock_stream_ops = { 1826 .family = PF_VSOCK, 1827 .owner = THIS_MODULE, 1828 .release = vsock_release, 1829 .bind = vsock_bind, 1830 .connect = vsock_stream_connect, 1831 .socketpair = sock_no_socketpair, 1832 .accept = vsock_accept, 1833 .getname = vsock_getname, 1834 .poll = vsock_poll, 1835 .ioctl = sock_no_ioctl, 1836 .listen = vsock_listen, 1837 .shutdown = vsock_shutdown, 1838 .setsockopt = vsock_stream_setsockopt, 1839 .getsockopt = vsock_stream_getsockopt, 1840 .sendmsg = vsock_stream_sendmsg, 1841 .recvmsg = vsock_stream_recvmsg, 1842 .mmap = sock_no_mmap, 1843 .sendpage = sock_no_sendpage, 1844 }; 1845 1846 static int vsock_create(struct net *net, struct socket *sock, 1847 int protocol, int kern) 1848 { 1849 if (!sock) 1850 return -EINVAL; 1851 1852 if (protocol && protocol != PF_VSOCK) 1853 return -EPROTONOSUPPORT; 1854 1855 switch (sock->type) { 1856 case SOCK_DGRAM: 1857 sock->ops = &vsock_dgram_ops; 1858 break; 1859 case SOCK_STREAM: 1860 sock->ops = &vsock_stream_ops; 1861 break; 1862 default: 1863 return -ESOCKTNOSUPPORT; 1864 } 1865 1866 sock->state = SS_UNCONNECTED; 1867 1868 return __vsock_create(net, sock, NULL, GFP_KERNEL, 0, kern) ? 0 : -ENOMEM; 1869 } 1870 1871 static const struct net_proto_family vsock_family_ops = { 1872 .family = AF_VSOCK, 1873 .create = vsock_create, 1874 .owner = THIS_MODULE, 1875 }; 1876 1877 static long vsock_dev_do_ioctl(struct file *filp, 1878 unsigned int cmd, void __user *ptr) 1879 { 1880 u32 __user *p = ptr; 1881 int retval = 0; 1882 1883 switch (cmd) { 1884 case IOCTL_VM_SOCKETS_GET_LOCAL_CID: 1885 if (put_user(transport->get_local_cid(), p) != 0) 1886 retval = -EFAULT; 1887 break; 1888 1889 default: 1890 pr_err("Unknown ioctl %d\n", cmd); 1891 retval = -EINVAL; 1892 } 1893 1894 return retval; 1895 } 1896 1897 static long vsock_dev_ioctl(struct file *filp, 1898 unsigned int cmd, unsigned long arg) 1899 { 1900 return vsock_dev_do_ioctl(filp, cmd, (void __user *)arg); 1901 } 1902 1903 #ifdef CONFIG_COMPAT 1904 static long vsock_dev_compat_ioctl(struct file *filp, 1905 unsigned int cmd, unsigned long arg) 1906 { 1907 return vsock_dev_do_ioctl(filp, cmd, compat_ptr(arg)); 1908 } 1909 #endif 1910 1911 static const struct file_operations vsock_device_ops = { 1912 .owner = THIS_MODULE, 1913 .unlocked_ioctl = vsock_dev_ioctl, 1914 #ifdef CONFIG_COMPAT 1915 .compat_ioctl = vsock_dev_compat_ioctl, 1916 #endif 1917 .open = nonseekable_open, 1918 }; 1919 1920 static struct miscdevice vsock_device = { 1921 .name = "vsock", 1922 .fops = &vsock_device_ops, 1923 }; 1924 1925 int __vsock_core_init(const struct vsock_transport *t, struct module *owner) 1926 { 1927 int err = mutex_lock_interruptible(&vsock_register_mutex); 1928 1929 if (err) 1930 return err; 1931 1932 if (transport) { 1933 err = -EBUSY; 1934 goto err_busy; 1935 } 1936 1937 /* Transport must be the owner of the protocol so that it can't 1938 * unload while there are open sockets. 1939 */ 1940 vsock_proto.owner = owner; 1941 transport = t; 1942 1943 vsock_device.minor = MISC_DYNAMIC_MINOR; 1944 err = misc_register(&vsock_device); 1945 if (err) { 1946 pr_err("Failed to register misc device\n"); 1947 goto err_reset_transport; 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_deregister_misc; 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 mutex_unlock(&vsock_register_mutex); 1964 return 0; 1965 1966 err_unregister_proto: 1967 proto_unregister(&vsock_proto); 1968 err_deregister_misc: 1969 misc_deregister(&vsock_device); 1970 err_reset_transport: 1971 transport = NULL; 1972 err_busy: 1973 mutex_unlock(&vsock_register_mutex); 1974 return err; 1975 } 1976 EXPORT_SYMBOL_GPL(__vsock_core_init); 1977 1978 void vsock_core_exit(void) 1979 { 1980 mutex_lock(&vsock_register_mutex); 1981 1982 misc_deregister(&vsock_device); 1983 sock_unregister(AF_VSOCK); 1984 proto_unregister(&vsock_proto); 1985 1986 /* We do not want the assignment below re-ordered. */ 1987 mb(); 1988 transport = NULL; 1989 1990 mutex_unlock(&vsock_register_mutex); 1991 } 1992 EXPORT_SYMBOL_GPL(vsock_core_exit); 1993 1994 const struct vsock_transport *vsock_core_get_transport(void) 1995 { 1996 /* vsock_register_mutex not taken since only the transport uses this 1997 * function and only while registered. 1998 */ 1999 return transport; 2000 } 2001 EXPORT_SYMBOL_GPL(vsock_core_get_transport); 2002 2003 static void __exit vsock_exit(void) 2004 { 2005 /* Do nothing. This function makes this module removable. */ 2006 } 2007 2008 module_init(vsock_init_tables); 2009 module_exit(vsock_exit); 2010 2011 MODULE_AUTHOR("VMware, Inc."); 2012 MODULE_DESCRIPTION("VMware Virtual Socket Family"); 2013 MODULE_VERSION("1.0.2.0-k"); 2014 MODULE_LICENSE("GPL v2"); 2015