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_single; 130 static DEFINE_MUTEX(vsock_register_mutex); 131 132 /**** UTILS ****/ 133 134 /* Each bound VSocket is stored in the bind hash table and each connected 135 * VSocket is stored in the connected hash table. 136 * 137 * Unbound sockets are all put on the same list attached to the end of the hash 138 * table (vsock_unbound_sockets). Bound sockets are added to the hash table in 139 * the bucket that their local address hashes to (vsock_bound_sockets(addr) 140 * represents the list that addr hashes to). 141 * 142 * Specifically, we initialize the vsock_bind_table array to a size of 143 * VSOCK_HASH_SIZE + 1 so that vsock_bind_table[0] through 144 * vsock_bind_table[VSOCK_HASH_SIZE - 1] are for bound sockets and 145 * vsock_bind_table[VSOCK_HASH_SIZE] is for unbound sockets. The hash function 146 * mods with VSOCK_HASH_SIZE to ensure this. 147 */ 148 #define MAX_PORT_RETRIES 24 149 150 #define VSOCK_HASH(addr) ((addr)->svm_port % VSOCK_HASH_SIZE) 151 #define vsock_bound_sockets(addr) (&vsock_bind_table[VSOCK_HASH(addr)]) 152 #define vsock_unbound_sockets (&vsock_bind_table[VSOCK_HASH_SIZE]) 153 154 /* XXX This can probably be implemented in a better way. */ 155 #define VSOCK_CONN_HASH(src, dst) \ 156 (((src)->svm_cid ^ (dst)->svm_port) % VSOCK_HASH_SIZE) 157 #define vsock_connected_sockets(src, dst) \ 158 (&vsock_connected_table[VSOCK_CONN_HASH(src, dst)]) 159 #define vsock_connected_sockets_vsk(vsk) \ 160 vsock_connected_sockets(&(vsk)->remote_addr, &(vsk)->local_addr) 161 162 struct list_head vsock_bind_table[VSOCK_HASH_SIZE + 1]; 163 EXPORT_SYMBOL_GPL(vsock_bind_table); 164 struct list_head vsock_connected_table[VSOCK_HASH_SIZE]; 165 EXPORT_SYMBOL_GPL(vsock_connected_table); 166 DEFINE_SPINLOCK(vsock_table_lock); 167 EXPORT_SYMBOL_GPL(vsock_table_lock); 168 169 /* Autobind this socket to the local address if necessary. */ 170 static int vsock_auto_bind(struct vsock_sock *vsk) 171 { 172 struct sock *sk = sk_vsock(vsk); 173 struct sockaddr_vm local_addr; 174 175 if (vsock_addr_bound(&vsk->local_addr)) 176 return 0; 177 vsock_addr_init(&local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 178 return __vsock_bind(sk, &local_addr); 179 } 180 181 static int __init vsock_init_tables(void) 182 { 183 int i; 184 185 for (i = 0; i < ARRAY_SIZE(vsock_bind_table); i++) 186 INIT_LIST_HEAD(&vsock_bind_table[i]); 187 188 for (i = 0; i < ARRAY_SIZE(vsock_connected_table); i++) 189 INIT_LIST_HEAD(&vsock_connected_table[i]); 190 return 0; 191 } 192 193 static void __vsock_insert_bound(struct list_head *list, 194 struct vsock_sock *vsk) 195 { 196 sock_hold(&vsk->sk); 197 list_add(&vsk->bound_table, list); 198 } 199 200 static void __vsock_insert_connected(struct list_head *list, 201 struct vsock_sock *vsk) 202 { 203 sock_hold(&vsk->sk); 204 list_add(&vsk->connected_table, list); 205 } 206 207 static void __vsock_remove_bound(struct vsock_sock *vsk) 208 { 209 list_del_init(&vsk->bound_table); 210 sock_put(&vsk->sk); 211 } 212 213 static void __vsock_remove_connected(struct vsock_sock *vsk) 214 { 215 list_del_init(&vsk->connected_table); 216 sock_put(&vsk->sk); 217 } 218 219 static struct sock *__vsock_find_bound_socket(struct sockaddr_vm *addr) 220 { 221 struct vsock_sock *vsk; 222 223 list_for_each_entry(vsk, vsock_bound_sockets(addr), bound_table) 224 if (addr->svm_port == vsk->local_addr.svm_port) 225 return sk_vsock(vsk); 226 227 return NULL; 228 } 229 230 static struct sock *__vsock_find_connected_socket(struct sockaddr_vm *src, 231 struct sockaddr_vm *dst) 232 { 233 struct vsock_sock *vsk; 234 235 list_for_each_entry(vsk, vsock_connected_sockets(src, dst), 236 connected_table) { 237 if (vsock_addr_equals_addr(src, &vsk->remote_addr) && 238 dst->svm_port == vsk->local_addr.svm_port) { 239 return sk_vsock(vsk); 240 } 241 } 242 243 return NULL; 244 } 245 246 static void vsock_insert_unbound(struct vsock_sock *vsk) 247 { 248 spin_lock_bh(&vsock_table_lock); 249 __vsock_insert_bound(vsock_unbound_sockets, vsk); 250 spin_unlock_bh(&vsock_table_lock); 251 } 252 253 void vsock_insert_connected(struct vsock_sock *vsk) 254 { 255 struct list_head *list = vsock_connected_sockets( 256 &vsk->remote_addr, &vsk->local_addr); 257 258 spin_lock_bh(&vsock_table_lock); 259 __vsock_insert_connected(list, vsk); 260 spin_unlock_bh(&vsock_table_lock); 261 } 262 EXPORT_SYMBOL_GPL(vsock_insert_connected); 263 264 void vsock_remove_bound(struct vsock_sock *vsk) 265 { 266 spin_lock_bh(&vsock_table_lock); 267 if (__vsock_in_bound_table(vsk)) 268 __vsock_remove_bound(vsk); 269 spin_unlock_bh(&vsock_table_lock); 270 } 271 EXPORT_SYMBOL_GPL(vsock_remove_bound); 272 273 void vsock_remove_connected(struct vsock_sock *vsk) 274 { 275 spin_lock_bh(&vsock_table_lock); 276 if (__vsock_in_connected_table(vsk)) 277 __vsock_remove_connected(vsk); 278 spin_unlock_bh(&vsock_table_lock); 279 } 280 EXPORT_SYMBOL_GPL(vsock_remove_connected); 281 282 struct sock *vsock_find_bound_socket(struct sockaddr_vm *addr) 283 { 284 struct sock *sk; 285 286 spin_lock_bh(&vsock_table_lock); 287 sk = __vsock_find_bound_socket(addr); 288 if (sk) 289 sock_hold(sk); 290 291 spin_unlock_bh(&vsock_table_lock); 292 293 return sk; 294 } 295 EXPORT_SYMBOL_GPL(vsock_find_bound_socket); 296 297 struct sock *vsock_find_connected_socket(struct sockaddr_vm *src, 298 struct sockaddr_vm *dst) 299 { 300 struct sock *sk; 301 302 spin_lock_bh(&vsock_table_lock); 303 sk = __vsock_find_connected_socket(src, dst); 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_connected_socket); 312 313 void vsock_remove_sock(struct vsock_sock *vsk) 314 { 315 vsock_remove_bound(vsk); 316 vsock_remove_connected(vsk); 317 } 318 EXPORT_SYMBOL_GPL(vsock_remove_sock); 319 320 void vsock_for_each_connected_socket(void (*fn)(struct sock *sk)) 321 { 322 int i; 323 324 spin_lock_bh(&vsock_table_lock); 325 326 for (i = 0; i < ARRAY_SIZE(vsock_connected_table); i++) { 327 struct vsock_sock *vsk; 328 list_for_each_entry(vsk, &vsock_connected_table[i], 329 connected_table) 330 fn(sk_vsock(vsk)); 331 } 332 333 spin_unlock_bh(&vsock_table_lock); 334 } 335 EXPORT_SYMBOL_GPL(vsock_for_each_connected_socket); 336 337 void vsock_add_pending(struct sock *listener, struct sock *pending) 338 { 339 struct vsock_sock *vlistener; 340 struct vsock_sock *vpending; 341 342 vlistener = vsock_sk(listener); 343 vpending = vsock_sk(pending); 344 345 sock_hold(pending); 346 sock_hold(listener); 347 list_add_tail(&vpending->pending_links, &vlistener->pending_links); 348 } 349 EXPORT_SYMBOL_GPL(vsock_add_pending); 350 351 void vsock_remove_pending(struct sock *listener, struct sock *pending) 352 { 353 struct vsock_sock *vpending = vsock_sk(pending); 354 355 list_del_init(&vpending->pending_links); 356 sock_put(listener); 357 sock_put(pending); 358 } 359 EXPORT_SYMBOL_GPL(vsock_remove_pending); 360 361 void vsock_enqueue_accept(struct sock *listener, struct sock *connected) 362 { 363 struct vsock_sock *vlistener; 364 struct vsock_sock *vconnected; 365 366 vlistener = vsock_sk(listener); 367 vconnected = vsock_sk(connected); 368 369 sock_hold(connected); 370 sock_hold(listener); 371 list_add_tail(&vconnected->accept_queue, &vlistener->accept_queue); 372 } 373 EXPORT_SYMBOL_GPL(vsock_enqueue_accept); 374 375 static struct sock *vsock_dequeue_accept(struct sock *listener) 376 { 377 struct vsock_sock *vlistener; 378 struct vsock_sock *vconnected; 379 380 vlistener = vsock_sk(listener); 381 382 if (list_empty(&vlistener->accept_queue)) 383 return NULL; 384 385 vconnected = list_entry(vlistener->accept_queue.next, 386 struct vsock_sock, accept_queue); 387 388 list_del_init(&vconnected->accept_queue); 389 sock_put(listener); 390 /* The caller will need a reference on the connected socket so we let 391 * it call sock_put(). 392 */ 393 394 return sk_vsock(vconnected); 395 } 396 397 static bool vsock_is_accept_queue_empty(struct sock *sk) 398 { 399 struct vsock_sock *vsk = vsock_sk(sk); 400 return list_empty(&vsk->accept_queue); 401 } 402 403 static bool vsock_is_pending(struct sock *sk) 404 { 405 struct vsock_sock *vsk = vsock_sk(sk); 406 return !list_empty(&vsk->pending_links); 407 } 408 409 static int vsock_send_shutdown(struct sock *sk, int mode) 410 { 411 struct vsock_sock *vsk = vsock_sk(sk); 412 413 return vsk->transport->shutdown(vsk, mode); 414 } 415 416 static void vsock_pending_work(struct work_struct *work) 417 { 418 struct sock *sk; 419 struct sock *listener; 420 struct vsock_sock *vsk; 421 bool cleanup; 422 423 vsk = container_of(work, struct vsock_sock, pending_work.work); 424 sk = sk_vsock(vsk); 425 listener = vsk->listener; 426 cleanup = true; 427 428 lock_sock(listener); 429 lock_sock_nested(sk, SINGLE_DEPTH_NESTING); 430 431 if (vsock_is_pending(sk)) { 432 vsock_remove_pending(listener, sk); 433 434 sk_acceptq_removed(listener); 435 } else if (!vsk->rejected) { 436 /* We are not on the pending list and accept() did not reject 437 * us, so we must have been accepted by our user process. We 438 * just need to drop our references to the sockets and be on 439 * our way. 440 */ 441 cleanup = false; 442 goto out; 443 } 444 445 /* We need to remove ourself from the global connected sockets list so 446 * incoming packets can't find this socket, and to reduce the reference 447 * count. 448 */ 449 vsock_remove_connected(vsk); 450 451 sk->sk_state = TCP_CLOSE; 452 453 out: 454 release_sock(sk); 455 release_sock(listener); 456 if (cleanup) 457 sock_put(sk); 458 459 sock_put(sk); 460 sock_put(listener); 461 } 462 463 /**** SOCKET OPERATIONS ****/ 464 465 static int __vsock_bind_stream(struct vsock_sock *vsk, 466 struct sockaddr_vm *addr) 467 { 468 static u32 port; 469 struct sockaddr_vm new_addr; 470 471 if (!port) 472 port = LAST_RESERVED_PORT + 1 + 473 prandom_u32_max(U32_MAX - LAST_RESERVED_PORT); 474 475 vsock_addr_init(&new_addr, addr->svm_cid, addr->svm_port); 476 477 if (addr->svm_port == VMADDR_PORT_ANY) { 478 bool found = false; 479 unsigned int i; 480 481 for (i = 0; i < MAX_PORT_RETRIES; i++) { 482 if (port <= LAST_RESERVED_PORT) 483 port = LAST_RESERVED_PORT + 1; 484 485 new_addr.svm_port = port++; 486 487 if (!__vsock_find_bound_socket(&new_addr)) { 488 found = true; 489 break; 490 } 491 } 492 493 if (!found) 494 return -EADDRNOTAVAIL; 495 } else { 496 /* If port is in reserved range, ensure caller 497 * has necessary privileges. 498 */ 499 if (addr->svm_port <= LAST_RESERVED_PORT && 500 !capable(CAP_NET_BIND_SERVICE)) { 501 return -EACCES; 502 } 503 504 if (__vsock_find_bound_socket(&new_addr)) 505 return -EADDRINUSE; 506 } 507 508 vsock_addr_init(&vsk->local_addr, new_addr.svm_cid, new_addr.svm_port); 509 510 /* Remove stream sockets from the unbound list and add them to the hash 511 * table for easy lookup by its address. The unbound list is simply an 512 * extra entry at the end of the hash table, a trick used by AF_UNIX. 513 */ 514 __vsock_remove_bound(vsk); 515 __vsock_insert_bound(vsock_bound_sockets(&vsk->local_addr), vsk); 516 517 return 0; 518 } 519 520 static int __vsock_bind_dgram(struct vsock_sock *vsk, 521 struct sockaddr_vm *addr) 522 { 523 return vsk->transport->dgram_bind(vsk, addr); 524 } 525 526 static int __vsock_bind(struct sock *sk, struct sockaddr_vm *addr) 527 { 528 struct vsock_sock *vsk = vsock_sk(sk); 529 u32 cid; 530 int retval; 531 532 /* First ensure this socket isn't already bound. */ 533 if (vsock_addr_bound(&vsk->local_addr)) 534 return -EINVAL; 535 536 /* Now bind to the provided address or select appropriate values if 537 * none are provided (VMADDR_CID_ANY and VMADDR_PORT_ANY). Note that 538 * like AF_INET prevents binding to a non-local IP address (in most 539 * cases), we only allow binding to the local CID. 540 */ 541 cid = vsk->transport->get_local_cid(); 542 if (addr->svm_cid != cid && addr->svm_cid != VMADDR_CID_ANY) 543 return -EADDRNOTAVAIL; 544 545 switch (sk->sk_socket->type) { 546 case SOCK_STREAM: 547 spin_lock_bh(&vsock_table_lock); 548 retval = __vsock_bind_stream(vsk, addr); 549 spin_unlock_bh(&vsock_table_lock); 550 break; 551 552 case SOCK_DGRAM: 553 retval = __vsock_bind_dgram(vsk, addr); 554 break; 555 556 default: 557 retval = -EINVAL; 558 break; 559 } 560 561 return retval; 562 } 563 564 static void vsock_connect_timeout(struct work_struct *work); 565 566 struct sock *__vsock_create(struct net *net, 567 struct socket *sock, 568 struct sock *parent, 569 gfp_t priority, 570 unsigned short type, 571 int kern) 572 { 573 struct sock *sk; 574 struct vsock_sock *psk; 575 struct vsock_sock *vsk; 576 577 sk = sk_alloc(net, AF_VSOCK, priority, &vsock_proto, kern); 578 if (!sk) 579 return NULL; 580 581 sock_init_data(sock, sk); 582 583 /* sk->sk_type is normally set in sock_init_data, but only if sock is 584 * non-NULL. We make sure that our sockets always have a type by 585 * setting it here if needed. 586 */ 587 if (!sock) 588 sk->sk_type = type; 589 590 vsk = vsock_sk(sk); 591 vsk->transport = transport_single; 592 vsock_addr_init(&vsk->local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 593 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 594 595 sk->sk_destruct = vsock_sk_destruct; 596 sk->sk_backlog_rcv = vsock_queue_rcv_skb; 597 sock_reset_flag(sk, SOCK_DONE); 598 599 INIT_LIST_HEAD(&vsk->bound_table); 600 INIT_LIST_HEAD(&vsk->connected_table); 601 vsk->listener = NULL; 602 INIT_LIST_HEAD(&vsk->pending_links); 603 INIT_LIST_HEAD(&vsk->accept_queue); 604 vsk->rejected = false; 605 vsk->sent_request = false; 606 vsk->ignore_connecting_rst = false; 607 vsk->peer_shutdown = 0; 608 INIT_DELAYED_WORK(&vsk->connect_work, vsock_connect_timeout); 609 INIT_DELAYED_WORK(&vsk->pending_work, vsock_pending_work); 610 611 psk = parent ? vsock_sk(parent) : NULL; 612 if (parent) { 613 vsk->trusted = psk->trusted; 614 vsk->owner = get_cred(psk->owner); 615 vsk->connect_timeout = psk->connect_timeout; 616 } else { 617 vsk->trusted = capable(CAP_NET_ADMIN); 618 vsk->owner = get_current_cred(); 619 vsk->connect_timeout = VSOCK_DEFAULT_CONNECT_TIMEOUT; 620 } 621 622 if (vsk->transport->init(vsk, psk) < 0) { 623 sk_free(sk); 624 return NULL; 625 } 626 627 if (sock) 628 vsock_insert_unbound(vsk); 629 630 return sk; 631 } 632 EXPORT_SYMBOL_GPL(__vsock_create); 633 634 static void __vsock_release(struct sock *sk, int level) 635 { 636 if (sk) { 637 struct sock *pending; 638 struct vsock_sock *vsk; 639 640 vsk = vsock_sk(sk); 641 pending = NULL; /* Compiler warning. */ 642 643 /* The release call is supposed to use lock_sock_nested() 644 * rather than lock_sock(), if a sock lock should be acquired. 645 */ 646 vsk->transport->release(vsk); 647 648 /* When "level" is SINGLE_DEPTH_NESTING, use the nested 649 * version to avoid the warning "possible recursive locking 650 * detected". When "level" is 0, lock_sock_nested(sk, level) 651 * is the same as lock_sock(sk). 652 */ 653 lock_sock_nested(sk, level); 654 sock_orphan(sk); 655 sk->sk_shutdown = SHUTDOWN_MASK; 656 657 skb_queue_purge(&sk->sk_receive_queue); 658 659 /* Clean up any sockets that never were accepted. */ 660 while ((pending = vsock_dequeue_accept(sk)) != NULL) { 661 __vsock_release(pending, SINGLE_DEPTH_NESTING); 662 sock_put(pending); 663 } 664 665 release_sock(sk); 666 sock_put(sk); 667 } 668 } 669 670 static void vsock_sk_destruct(struct sock *sk) 671 { 672 struct vsock_sock *vsk = vsock_sk(sk); 673 674 vsk->transport->destruct(vsk); 675 676 /* When clearing these addresses, there's no need to set the family and 677 * possibly register the address family with the kernel. 678 */ 679 vsock_addr_init(&vsk->local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 680 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 681 682 put_cred(vsk->owner); 683 } 684 685 static int vsock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 686 { 687 int err; 688 689 err = sock_queue_rcv_skb(sk, skb); 690 if (err) 691 kfree_skb(skb); 692 693 return err; 694 } 695 696 s64 vsock_stream_has_data(struct vsock_sock *vsk) 697 { 698 return vsk->transport->stream_has_data(vsk); 699 } 700 EXPORT_SYMBOL_GPL(vsock_stream_has_data); 701 702 s64 vsock_stream_has_space(struct vsock_sock *vsk) 703 { 704 return vsk->transport->stream_has_space(vsk); 705 } 706 EXPORT_SYMBOL_GPL(vsock_stream_has_space); 707 708 static int vsock_release(struct socket *sock) 709 { 710 __vsock_release(sock->sk, 0); 711 sock->sk = NULL; 712 sock->state = SS_FREE; 713 714 return 0; 715 } 716 717 static int 718 vsock_bind(struct socket *sock, struct sockaddr *addr, int addr_len) 719 { 720 int err; 721 struct sock *sk; 722 struct sockaddr_vm *vm_addr; 723 724 sk = sock->sk; 725 726 if (vsock_addr_cast(addr, addr_len, &vm_addr) != 0) 727 return -EINVAL; 728 729 lock_sock(sk); 730 err = __vsock_bind(sk, vm_addr); 731 release_sock(sk); 732 733 return err; 734 } 735 736 static int vsock_getname(struct socket *sock, 737 struct sockaddr *addr, int peer) 738 { 739 int err; 740 struct sock *sk; 741 struct vsock_sock *vsk; 742 struct sockaddr_vm *vm_addr; 743 744 sk = sock->sk; 745 vsk = vsock_sk(sk); 746 err = 0; 747 748 lock_sock(sk); 749 750 if (peer) { 751 if (sock->state != SS_CONNECTED) { 752 err = -ENOTCONN; 753 goto out; 754 } 755 vm_addr = &vsk->remote_addr; 756 } else { 757 vm_addr = &vsk->local_addr; 758 } 759 760 if (!vm_addr) { 761 err = -EINVAL; 762 goto out; 763 } 764 765 /* sys_getsockname() and sys_getpeername() pass us a 766 * MAX_SOCK_ADDR-sized buffer and don't set addr_len. Unfortunately 767 * that macro is defined in socket.c instead of .h, so we hardcode its 768 * value here. 769 */ 770 BUILD_BUG_ON(sizeof(*vm_addr) > 128); 771 memcpy(addr, vm_addr, sizeof(*vm_addr)); 772 err = sizeof(*vm_addr); 773 774 out: 775 release_sock(sk); 776 return err; 777 } 778 779 static int vsock_shutdown(struct socket *sock, int mode) 780 { 781 int err; 782 struct sock *sk; 783 784 /* User level uses SHUT_RD (0) and SHUT_WR (1), but the kernel uses 785 * RCV_SHUTDOWN (1) and SEND_SHUTDOWN (2), so we must increment mode 786 * here like the other address families do. Note also that the 787 * increment makes SHUT_RDWR (2) into RCV_SHUTDOWN | SEND_SHUTDOWN (3), 788 * which is what we want. 789 */ 790 mode++; 791 792 if ((mode & ~SHUTDOWN_MASK) || !mode) 793 return -EINVAL; 794 795 /* If this is a STREAM socket and it is not connected then bail out 796 * immediately. If it is a DGRAM socket then we must first kick the 797 * socket so that it wakes up from any sleeping calls, for example 798 * recv(), and then afterwards return the error. 799 */ 800 801 sk = sock->sk; 802 if (sock->state == SS_UNCONNECTED) { 803 err = -ENOTCONN; 804 if (sk->sk_type == SOCK_STREAM) 805 return err; 806 } else { 807 sock->state = SS_DISCONNECTING; 808 err = 0; 809 } 810 811 /* Receive and send shutdowns are treated alike. */ 812 mode = mode & (RCV_SHUTDOWN | SEND_SHUTDOWN); 813 if (mode) { 814 lock_sock(sk); 815 sk->sk_shutdown |= mode; 816 sk->sk_state_change(sk); 817 release_sock(sk); 818 819 if (sk->sk_type == SOCK_STREAM) { 820 sock_reset_flag(sk, SOCK_DONE); 821 vsock_send_shutdown(sk, mode); 822 } 823 } 824 825 return err; 826 } 827 828 static __poll_t vsock_poll(struct file *file, struct socket *sock, 829 poll_table *wait) 830 { 831 struct sock *sk; 832 __poll_t mask; 833 struct vsock_sock *vsk; 834 835 sk = sock->sk; 836 vsk = vsock_sk(sk); 837 838 poll_wait(file, sk_sleep(sk), wait); 839 mask = 0; 840 841 if (sk->sk_err) 842 /* Signify that there has been an error on this socket. */ 843 mask |= EPOLLERR; 844 845 /* INET sockets treat local write shutdown and peer write shutdown as a 846 * case of EPOLLHUP set. 847 */ 848 if ((sk->sk_shutdown == SHUTDOWN_MASK) || 849 ((sk->sk_shutdown & SEND_SHUTDOWN) && 850 (vsk->peer_shutdown & SEND_SHUTDOWN))) { 851 mask |= EPOLLHUP; 852 } 853 854 if (sk->sk_shutdown & RCV_SHUTDOWN || 855 vsk->peer_shutdown & SEND_SHUTDOWN) { 856 mask |= EPOLLRDHUP; 857 } 858 859 if (sock->type == SOCK_DGRAM) { 860 /* For datagram sockets we can read if there is something in 861 * the queue and write as long as the socket isn't shutdown for 862 * sending. 863 */ 864 if (!skb_queue_empty_lockless(&sk->sk_receive_queue) || 865 (sk->sk_shutdown & RCV_SHUTDOWN)) { 866 mask |= EPOLLIN | EPOLLRDNORM; 867 } 868 869 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) 870 mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND; 871 872 } else if (sock->type == SOCK_STREAM) { 873 const struct vsock_transport *transport = vsk->transport; 874 lock_sock(sk); 875 876 /* Listening sockets that have connections in their accept 877 * queue can be read. 878 */ 879 if (sk->sk_state == TCP_LISTEN 880 && !vsock_is_accept_queue_empty(sk)) 881 mask |= EPOLLIN | EPOLLRDNORM; 882 883 /* If there is something in the queue then we can read. */ 884 if (transport->stream_is_active(vsk) && 885 !(sk->sk_shutdown & RCV_SHUTDOWN)) { 886 bool data_ready_now = false; 887 int ret = transport->notify_poll_in( 888 vsk, 1, &data_ready_now); 889 if (ret < 0) { 890 mask |= EPOLLERR; 891 } else { 892 if (data_ready_now) 893 mask |= EPOLLIN | EPOLLRDNORM; 894 895 } 896 } 897 898 /* Sockets whose connections have been closed, reset, or 899 * terminated should also be considered read, and we check the 900 * shutdown flag for that. 901 */ 902 if (sk->sk_shutdown & RCV_SHUTDOWN || 903 vsk->peer_shutdown & SEND_SHUTDOWN) { 904 mask |= EPOLLIN | EPOLLRDNORM; 905 } 906 907 /* Connected sockets that can produce data can be written. */ 908 if (sk->sk_state == TCP_ESTABLISHED) { 909 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) { 910 bool space_avail_now = false; 911 int ret = transport->notify_poll_out( 912 vsk, 1, &space_avail_now); 913 if (ret < 0) { 914 mask |= EPOLLERR; 915 } else { 916 if (space_avail_now) 917 /* Remove EPOLLWRBAND since INET 918 * sockets are not setting it. 919 */ 920 mask |= EPOLLOUT | EPOLLWRNORM; 921 922 } 923 } 924 } 925 926 /* Simulate INET socket poll behaviors, which sets 927 * EPOLLOUT|EPOLLWRNORM when peer is closed and nothing to read, 928 * but local send is not shutdown. 929 */ 930 if (sk->sk_state == TCP_CLOSE || sk->sk_state == TCP_CLOSING) { 931 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) 932 mask |= EPOLLOUT | EPOLLWRNORM; 933 934 } 935 936 release_sock(sk); 937 } 938 939 return mask; 940 } 941 942 static int vsock_dgram_sendmsg(struct socket *sock, struct msghdr *msg, 943 size_t len) 944 { 945 int err; 946 struct sock *sk; 947 struct vsock_sock *vsk; 948 struct sockaddr_vm *remote_addr; 949 const struct vsock_transport *transport; 950 951 if (msg->msg_flags & MSG_OOB) 952 return -EOPNOTSUPP; 953 954 /* For now, MSG_DONTWAIT is always assumed... */ 955 err = 0; 956 sk = sock->sk; 957 vsk = vsock_sk(sk); 958 transport = vsk->transport; 959 960 lock_sock(sk); 961 962 err = vsock_auto_bind(vsk); 963 if (err) 964 goto out; 965 966 967 /* If the provided message contains an address, use that. Otherwise 968 * fall back on the socket's remote handle (if it has been connected). 969 */ 970 if (msg->msg_name && 971 vsock_addr_cast(msg->msg_name, msg->msg_namelen, 972 &remote_addr) == 0) { 973 /* Ensure this address is of the right type and is a valid 974 * destination. 975 */ 976 977 if (remote_addr->svm_cid == VMADDR_CID_ANY) 978 remote_addr->svm_cid = transport->get_local_cid(); 979 980 if (!vsock_addr_bound(remote_addr)) { 981 err = -EINVAL; 982 goto out; 983 } 984 } else if (sock->state == SS_CONNECTED) { 985 remote_addr = &vsk->remote_addr; 986 987 if (remote_addr->svm_cid == VMADDR_CID_ANY) 988 remote_addr->svm_cid = transport->get_local_cid(); 989 990 /* XXX Should connect() or this function ensure remote_addr is 991 * bound? 992 */ 993 if (!vsock_addr_bound(&vsk->remote_addr)) { 994 err = -EINVAL; 995 goto out; 996 } 997 } else { 998 err = -EINVAL; 999 goto out; 1000 } 1001 1002 if (!transport->dgram_allow(remote_addr->svm_cid, 1003 remote_addr->svm_port)) { 1004 err = -EINVAL; 1005 goto out; 1006 } 1007 1008 err = transport->dgram_enqueue(vsk, remote_addr, msg, len); 1009 1010 out: 1011 release_sock(sk); 1012 return err; 1013 } 1014 1015 static int vsock_dgram_connect(struct socket *sock, 1016 struct sockaddr *addr, int addr_len, int flags) 1017 { 1018 int err; 1019 struct sock *sk; 1020 struct vsock_sock *vsk; 1021 struct sockaddr_vm *remote_addr; 1022 1023 sk = sock->sk; 1024 vsk = vsock_sk(sk); 1025 1026 err = vsock_addr_cast(addr, addr_len, &remote_addr); 1027 if (err == -EAFNOSUPPORT && remote_addr->svm_family == AF_UNSPEC) { 1028 lock_sock(sk); 1029 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, 1030 VMADDR_PORT_ANY); 1031 sock->state = SS_UNCONNECTED; 1032 release_sock(sk); 1033 return 0; 1034 } else if (err != 0) 1035 return -EINVAL; 1036 1037 lock_sock(sk); 1038 1039 err = vsock_auto_bind(vsk); 1040 if (err) 1041 goto out; 1042 1043 if (!vsk->transport->dgram_allow(remote_addr->svm_cid, 1044 remote_addr->svm_port)) { 1045 err = -EINVAL; 1046 goto out; 1047 } 1048 1049 memcpy(&vsk->remote_addr, remote_addr, sizeof(vsk->remote_addr)); 1050 sock->state = SS_CONNECTED; 1051 1052 out: 1053 release_sock(sk); 1054 return err; 1055 } 1056 1057 static int vsock_dgram_recvmsg(struct socket *sock, struct msghdr *msg, 1058 size_t len, int flags) 1059 { 1060 struct vsock_sock *vsk = vsock_sk(sock->sk); 1061 1062 return vsk->transport->dgram_dequeue(vsk, msg, len, flags); 1063 } 1064 1065 static const struct proto_ops vsock_dgram_ops = { 1066 .family = PF_VSOCK, 1067 .owner = THIS_MODULE, 1068 .release = vsock_release, 1069 .bind = vsock_bind, 1070 .connect = vsock_dgram_connect, 1071 .socketpair = sock_no_socketpair, 1072 .accept = sock_no_accept, 1073 .getname = vsock_getname, 1074 .poll = vsock_poll, 1075 .ioctl = sock_no_ioctl, 1076 .listen = sock_no_listen, 1077 .shutdown = vsock_shutdown, 1078 .setsockopt = sock_no_setsockopt, 1079 .getsockopt = sock_no_getsockopt, 1080 .sendmsg = vsock_dgram_sendmsg, 1081 .recvmsg = vsock_dgram_recvmsg, 1082 .mmap = sock_no_mmap, 1083 .sendpage = sock_no_sendpage, 1084 }; 1085 1086 static int vsock_transport_cancel_pkt(struct vsock_sock *vsk) 1087 { 1088 const struct vsock_transport *transport = vsk->transport; 1089 1090 if (!transport->cancel_pkt) 1091 return -EOPNOTSUPP; 1092 1093 return transport->cancel_pkt(vsk); 1094 } 1095 1096 static void vsock_connect_timeout(struct work_struct *work) 1097 { 1098 struct sock *sk; 1099 struct vsock_sock *vsk; 1100 int cancel = 0; 1101 1102 vsk = container_of(work, struct vsock_sock, connect_work.work); 1103 sk = sk_vsock(vsk); 1104 1105 lock_sock(sk); 1106 if (sk->sk_state == TCP_SYN_SENT && 1107 (sk->sk_shutdown != SHUTDOWN_MASK)) { 1108 sk->sk_state = TCP_CLOSE; 1109 sk->sk_err = ETIMEDOUT; 1110 sk->sk_error_report(sk); 1111 cancel = 1; 1112 } 1113 release_sock(sk); 1114 if (cancel) 1115 vsock_transport_cancel_pkt(vsk); 1116 1117 sock_put(sk); 1118 } 1119 1120 static int vsock_stream_connect(struct socket *sock, struct sockaddr *addr, 1121 int addr_len, int flags) 1122 { 1123 int err; 1124 struct sock *sk; 1125 struct vsock_sock *vsk; 1126 const struct vsock_transport *transport; 1127 struct sockaddr_vm *remote_addr; 1128 long timeout; 1129 DEFINE_WAIT(wait); 1130 1131 err = 0; 1132 sk = sock->sk; 1133 vsk = vsock_sk(sk); 1134 transport = vsk->transport; 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 sk_acceptq_removed(listener); 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 const struct vsock_transport *transport; 1379 u64 val; 1380 1381 if (level != AF_VSOCK) 1382 return -ENOPROTOOPT; 1383 1384 #define COPY_IN(_v) \ 1385 do { \ 1386 if (optlen < sizeof(_v)) { \ 1387 err = -EINVAL; \ 1388 goto exit; \ 1389 } \ 1390 if (copy_from_user(&_v, optval, sizeof(_v)) != 0) { \ 1391 err = -EFAULT; \ 1392 goto exit; \ 1393 } \ 1394 } while (0) 1395 1396 err = 0; 1397 sk = sock->sk; 1398 vsk = vsock_sk(sk); 1399 transport = vsk->transport; 1400 1401 lock_sock(sk); 1402 1403 switch (optname) { 1404 case SO_VM_SOCKETS_BUFFER_SIZE: 1405 COPY_IN(val); 1406 transport->set_buffer_size(vsk, val); 1407 break; 1408 1409 case SO_VM_SOCKETS_BUFFER_MAX_SIZE: 1410 COPY_IN(val); 1411 transport->set_max_buffer_size(vsk, val); 1412 break; 1413 1414 case SO_VM_SOCKETS_BUFFER_MIN_SIZE: 1415 COPY_IN(val); 1416 transport->set_min_buffer_size(vsk, val); 1417 break; 1418 1419 case SO_VM_SOCKETS_CONNECT_TIMEOUT: { 1420 struct __kernel_old_timeval tv; 1421 COPY_IN(tv); 1422 if (tv.tv_sec >= 0 && tv.tv_usec < USEC_PER_SEC && 1423 tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)) { 1424 vsk->connect_timeout = tv.tv_sec * HZ + 1425 DIV_ROUND_UP(tv.tv_usec, (1000000 / HZ)); 1426 if (vsk->connect_timeout == 0) 1427 vsk->connect_timeout = 1428 VSOCK_DEFAULT_CONNECT_TIMEOUT; 1429 1430 } else { 1431 err = -ERANGE; 1432 } 1433 break; 1434 } 1435 1436 default: 1437 err = -ENOPROTOOPT; 1438 break; 1439 } 1440 1441 #undef COPY_IN 1442 1443 exit: 1444 release_sock(sk); 1445 return err; 1446 } 1447 1448 static int vsock_stream_getsockopt(struct socket *sock, 1449 int level, int optname, 1450 char __user *optval, 1451 int __user *optlen) 1452 { 1453 int err; 1454 int len; 1455 struct sock *sk; 1456 struct vsock_sock *vsk; 1457 const struct vsock_transport *transport; 1458 u64 val; 1459 1460 if (level != AF_VSOCK) 1461 return -ENOPROTOOPT; 1462 1463 err = get_user(len, optlen); 1464 if (err != 0) 1465 return err; 1466 1467 #define COPY_OUT(_v) \ 1468 do { \ 1469 if (len < sizeof(_v)) \ 1470 return -EINVAL; \ 1471 \ 1472 len = sizeof(_v); \ 1473 if (copy_to_user(optval, &_v, len) != 0) \ 1474 return -EFAULT; \ 1475 \ 1476 } while (0) 1477 1478 err = 0; 1479 sk = sock->sk; 1480 vsk = vsock_sk(sk); 1481 transport = vsk->transport; 1482 1483 switch (optname) { 1484 case SO_VM_SOCKETS_BUFFER_SIZE: 1485 val = transport->get_buffer_size(vsk); 1486 COPY_OUT(val); 1487 break; 1488 1489 case SO_VM_SOCKETS_BUFFER_MAX_SIZE: 1490 val = transport->get_max_buffer_size(vsk); 1491 COPY_OUT(val); 1492 break; 1493 1494 case SO_VM_SOCKETS_BUFFER_MIN_SIZE: 1495 val = transport->get_min_buffer_size(vsk); 1496 COPY_OUT(val); 1497 break; 1498 1499 case SO_VM_SOCKETS_CONNECT_TIMEOUT: { 1500 struct __kernel_old_timeval tv; 1501 tv.tv_sec = vsk->connect_timeout / HZ; 1502 tv.tv_usec = 1503 (vsk->connect_timeout - 1504 tv.tv_sec * HZ) * (1000000 / HZ); 1505 COPY_OUT(tv); 1506 break; 1507 } 1508 default: 1509 return -ENOPROTOOPT; 1510 } 1511 1512 err = put_user(len, optlen); 1513 if (err != 0) 1514 return -EFAULT; 1515 1516 #undef COPY_OUT 1517 1518 return 0; 1519 } 1520 1521 static int vsock_stream_sendmsg(struct socket *sock, struct msghdr *msg, 1522 size_t len) 1523 { 1524 struct sock *sk; 1525 struct vsock_sock *vsk; 1526 const struct vsock_transport *transport; 1527 ssize_t total_written; 1528 long timeout; 1529 int err; 1530 struct vsock_transport_send_notify_data send_data; 1531 DEFINE_WAIT_FUNC(wait, woken_wake_function); 1532 1533 sk = sock->sk; 1534 vsk = vsock_sk(sk); 1535 transport = vsk->transport; 1536 total_written = 0; 1537 err = 0; 1538 1539 if (msg->msg_flags & MSG_OOB) 1540 return -EOPNOTSUPP; 1541 1542 lock_sock(sk); 1543 1544 /* Callers should not provide a destination with stream sockets. */ 1545 if (msg->msg_namelen) { 1546 err = sk->sk_state == TCP_ESTABLISHED ? -EISCONN : -EOPNOTSUPP; 1547 goto out; 1548 } 1549 1550 /* Send data only if both sides are not shutdown in the direction. */ 1551 if (sk->sk_shutdown & SEND_SHUTDOWN || 1552 vsk->peer_shutdown & RCV_SHUTDOWN) { 1553 err = -EPIPE; 1554 goto out; 1555 } 1556 1557 if (sk->sk_state != TCP_ESTABLISHED || 1558 !vsock_addr_bound(&vsk->local_addr)) { 1559 err = -ENOTCONN; 1560 goto out; 1561 } 1562 1563 if (!vsock_addr_bound(&vsk->remote_addr)) { 1564 err = -EDESTADDRREQ; 1565 goto out; 1566 } 1567 1568 /* Wait for room in the produce queue to enqueue our user's data. */ 1569 timeout = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT); 1570 1571 err = transport->notify_send_init(vsk, &send_data); 1572 if (err < 0) 1573 goto out; 1574 1575 while (total_written < len) { 1576 ssize_t written; 1577 1578 add_wait_queue(sk_sleep(sk), &wait); 1579 while (vsock_stream_has_space(vsk) == 0 && 1580 sk->sk_err == 0 && 1581 !(sk->sk_shutdown & SEND_SHUTDOWN) && 1582 !(vsk->peer_shutdown & RCV_SHUTDOWN)) { 1583 1584 /* Don't wait for non-blocking sockets. */ 1585 if (timeout == 0) { 1586 err = -EAGAIN; 1587 remove_wait_queue(sk_sleep(sk), &wait); 1588 goto out_err; 1589 } 1590 1591 err = transport->notify_send_pre_block(vsk, &send_data); 1592 if (err < 0) { 1593 remove_wait_queue(sk_sleep(sk), &wait); 1594 goto out_err; 1595 } 1596 1597 release_sock(sk); 1598 timeout = wait_woken(&wait, TASK_INTERRUPTIBLE, timeout); 1599 lock_sock(sk); 1600 if (signal_pending(current)) { 1601 err = sock_intr_errno(timeout); 1602 remove_wait_queue(sk_sleep(sk), &wait); 1603 goto out_err; 1604 } else if (timeout == 0) { 1605 err = -EAGAIN; 1606 remove_wait_queue(sk_sleep(sk), &wait); 1607 goto out_err; 1608 } 1609 } 1610 remove_wait_queue(sk_sleep(sk), &wait); 1611 1612 /* These checks occur both as part of and after the loop 1613 * conditional since we need to check before and after 1614 * sleeping. 1615 */ 1616 if (sk->sk_err) { 1617 err = -sk->sk_err; 1618 goto out_err; 1619 } else if ((sk->sk_shutdown & SEND_SHUTDOWN) || 1620 (vsk->peer_shutdown & RCV_SHUTDOWN)) { 1621 err = -EPIPE; 1622 goto out_err; 1623 } 1624 1625 err = transport->notify_send_pre_enqueue(vsk, &send_data); 1626 if (err < 0) 1627 goto out_err; 1628 1629 /* Note that enqueue will only write as many bytes as are free 1630 * in the produce queue, so we don't need to ensure len is 1631 * smaller than the queue size. It is the caller's 1632 * responsibility to check how many bytes we were able to send. 1633 */ 1634 1635 written = transport->stream_enqueue( 1636 vsk, msg, 1637 len - total_written); 1638 if (written < 0) { 1639 err = -ENOMEM; 1640 goto out_err; 1641 } 1642 1643 total_written += written; 1644 1645 err = transport->notify_send_post_enqueue( 1646 vsk, written, &send_data); 1647 if (err < 0) 1648 goto out_err; 1649 1650 } 1651 1652 out_err: 1653 if (total_written > 0) 1654 err = total_written; 1655 out: 1656 release_sock(sk); 1657 return err; 1658 } 1659 1660 1661 static int 1662 vsock_stream_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, 1663 int flags) 1664 { 1665 struct sock *sk; 1666 struct vsock_sock *vsk; 1667 const struct vsock_transport *transport; 1668 int err; 1669 size_t target; 1670 ssize_t copied; 1671 long timeout; 1672 struct vsock_transport_recv_notify_data recv_data; 1673 1674 DEFINE_WAIT(wait); 1675 1676 sk = sock->sk; 1677 vsk = vsock_sk(sk); 1678 transport = vsk->transport; 1679 err = 0; 1680 1681 lock_sock(sk); 1682 1683 if (sk->sk_state != TCP_ESTABLISHED) { 1684 /* Recvmsg is supposed to return 0 if a peer performs an 1685 * orderly shutdown. Differentiate between that case and when a 1686 * peer has not connected or a local shutdown occured with the 1687 * SOCK_DONE flag. 1688 */ 1689 if (sock_flag(sk, SOCK_DONE)) 1690 err = 0; 1691 else 1692 err = -ENOTCONN; 1693 1694 goto out; 1695 } 1696 1697 if (flags & MSG_OOB) { 1698 err = -EOPNOTSUPP; 1699 goto out; 1700 } 1701 1702 /* We don't check peer_shutdown flag here since peer may actually shut 1703 * down, but there can be data in the queue that a local socket can 1704 * receive. 1705 */ 1706 if (sk->sk_shutdown & RCV_SHUTDOWN) { 1707 err = 0; 1708 goto out; 1709 } 1710 1711 /* It is valid on Linux to pass in a zero-length receive buffer. This 1712 * is not an error. We may as well bail out now. 1713 */ 1714 if (!len) { 1715 err = 0; 1716 goto out; 1717 } 1718 1719 /* We must not copy less than target bytes into the user's buffer 1720 * before returning successfully, so we wait for the consume queue to 1721 * have that much data to consume before dequeueing. Note that this 1722 * makes it impossible to handle cases where target is greater than the 1723 * queue size. 1724 */ 1725 target = sock_rcvlowat(sk, flags & MSG_WAITALL, len); 1726 if (target >= transport->stream_rcvhiwat(vsk)) { 1727 err = -ENOMEM; 1728 goto out; 1729 } 1730 timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); 1731 copied = 0; 1732 1733 err = transport->notify_recv_init(vsk, target, &recv_data); 1734 if (err < 0) 1735 goto out; 1736 1737 1738 while (1) { 1739 s64 ready; 1740 1741 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1742 ready = vsock_stream_has_data(vsk); 1743 1744 if (ready == 0) { 1745 if (sk->sk_err != 0 || 1746 (sk->sk_shutdown & RCV_SHUTDOWN) || 1747 (vsk->peer_shutdown & SEND_SHUTDOWN)) { 1748 finish_wait(sk_sleep(sk), &wait); 1749 break; 1750 } 1751 /* Don't wait for non-blocking sockets. */ 1752 if (timeout == 0) { 1753 err = -EAGAIN; 1754 finish_wait(sk_sleep(sk), &wait); 1755 break; 1756 } 1757 1758 err = transport->notify_recv_pre_block( 1759 vsk, target, &recv_data); 1760 if (err < 0) { 1761 finish_wait(sk_sleep(sk), &wait); 1762 break; 1763 } 1764 release_sock(sk); 1765 timeout = schedule_timeout(timeout); 1766 lock_sock(sk); 1767 1768 if (signal_pending(current)) { 1769 err = sock_intr_errno(timeout); 1770 finish_wait(sk_sleep(sk), &wait); 1771 break; 1772 } else if (timeout == 0) { 1773 err = -EAGAIN; 1774 finish_wait(sk_sleep(sk), &wait); 1775 break; 1776 } 1777 } else { 1778 ssize_t read; 1779 1780 finish_wait(sk_sleep(sk), &wait); 1781 1782 if (ready < 0) { 1783 /* Invalid queue pair content. XXX This should 1784 * be changed to a connection reset in a later 1785 * change. 1786 */ 1787 1788 err = -ENOMEM; 1789 goto out; 1790 } 1791 1792 err = transport->notify_recv_pre_dequeue( 1793 vsk, target, &recv_data); 1794 if (err < 0) 1795 break; 1796 1797 read = transport->stream_dequeue( 1798 vsk, msg, 1799 len - copied, flags); 1800 if (read < 0) { 1801 err = -ENOMEM; 1802 break; 1803 } 1804 1805 copied += read; 1806 1807 err = transport->notify_recv_post_dequeue( 1808 vsk, target, read, 1809 !(flags & MSG_PEEK), &recv_data); 1810 if (err < 0) 1811 goto out; 1812 1813 if (read >= target || flags & MSG_PEEK) 1814 break; 1815 1816 target -= read; 1817 } 1818 } 1819 1820 if (sk->sk_err) 1821 err = -sk->sk_err; 1822 else if (sk->sk_shutdown & RCV_SHUTDOWN) 1823 err = 0; 1824 1825 if (copied > 0) 1826 err = copied; 1827 1828 out: 1829 release_sock(sk); 1830 return err; 1831 } 1832 1833 static const struct proto_ops vsock_stream_ops = { 1834 .family = PF_VSOCK, 1835 .owner = THIS_MODULE, 1836 .release = vsock_release, 1837 .bind = vsock_bind, 1838 .connect = vsock_stream_connect, 1839 .socketpair = sock_no_socketpair, 1840 .accept = vsock_accept, 1841 .getname = vsock_getname, 1842 .poll = vsock_poll, 1843 .ioctl = sock_no_ioctl, 1844 .listen = vsock_listen, 1845 .shutdown = vsock_shutdown, 1846 .setsockopt = vsock_stream_setsockopt, 1847 .getsockopt = vsock_stream_getsockopt, 1848 .sendmsg = vsock_stream_sendmsg, 1849 .recvmsg = vsock_stream_recvmsg, 1850 .mmap = sock_no_mmap, 1851 .sendpage = sock_no_sendpage, 1852 }; 1853 1854 static int vsock_create(struct net *net, struct socket *sock, 1855 int protocol, int kern) 1856 { 1857 if (!sock) 1858 return -EINVAL; 1859 1860 if (protocol && protocol != PF_VSOCK) 1861 return -EPROTONOSUPPORT; 1862 1863 switch (sock->type) { 1864 case SOCK_DGRAM: 1865 sock->ops = &vsock_dgram_ops; 1866 break; 1867 case SOCK_STREAM: 1868 sock->ops = &vsock_stream_ops; 1869 break; 1870 default: 1871 return -ESOCKTNOSUPPORT; 1872 } 1873 1874 sock->state = SS_UNCONNECTED; 1875 1876 return __vsock_create(net, sock, NULL, GFP_KERNEL, 0, kern) ? 0 : -ENOMEM; 1877 } 1878 1879 static const struct net_proto_family vsock_family_ops = { 1880 .family = AF_VSOCK, 1881 .create = vsock_create, 1882 .owner = THIS_MODULE, 1883 }; 1884 1885 static long vsock_dev_do_ioctl(struct file *filp, 1886 unsigned int cmd, void __user *ptr) 1887 { 1888 u32 __user *p = ptr; 1889 int retval = 0; 1890 1891 switch (cmd) { 1892 case IOCTL_VM_SOCKETS_GET_LOCAL_CID: 1893 if (put_user(transport_single->get_local_cid(), p) != 0) 1894 retval = -EFAULT; 1895 break; 1896 1897 default: 1898 pr_err("Unknown ioctl %d\n", cmd); 1899 retval = -EINVAL; 1900 } 1901 1902 return retval; 1903 } 1904 1905 static long vsock_dev_ioctl(struct file *filp, 1906 unsigned int cmd, unsigned long arg) 1907 { 1908 return vsock_dev_do_ioctl(filp, cmd, (void __user *)arg); 1909 } 1910 1911 #ifdef CONFIG_COMPAT 1912 static long vsock_dev_compat_ioctl(struct file *filp, 1913 unsigned int cmd, unsigned long arg) 1914 { 1915 return vsock_dev_do_ioctl(filp, cmd, compat_ptr(arg)); 1916 } 1917 #endif 1918 1919 static const struct file_operations vsock_device_ops = { 1920 .owner = THIS_MODULE, 1921 .unlocked_ioctl = vsock_dev_ioctl, 1922 #ifdef CONFIG_COMPAT 1923 .compat_ioctl = vsock_dev_compat_ioctl, 1924 #endif 1925 .open = nonseekable_open, 1926 }; 1927 1928 static struct miscdevice vsock_device = { 1929 .name = "vsock", 1930 .fops = &vsock_device_ops, 1931 }; 1932 1933 int __vsock_core_init(const struct vsock_transport *t, struct module *owner) 1934 { 1935 int err = mutex_lock_interruptible(&vsock_register_mutex); 1936 1937 if (err) 1938 return err; 1939 1940 if (transport_single) { 1941 err = -EBUSY; 1942 goto err_busy; 1943 } 1944 1945 /* Transport must be the owner of the protocol so that it can't 1946 * unload while there are open sockets. 1947 */ 1948 vsock_proto.owner = owner; 1949 transport_single = t; 1950 1951 vsock_device.minor = MISC_DYNAMIC_MINOR; 1952 err = misc_register(&vsock_device); 1953 if (err) { 1954 pr_err("Failed to register misc device\n"); 1955 goto err_reset_transport; 1956 } 1957 1958 err = proto_register(&vsock_proto, 1); /* we want our slab */ 1959 if (err) { 1960 pr_err("Cannot register vsock protocol\n"); 1961 goto err_deregister_misc; 1962 } 1963 1964 err = sock_register(&vsock_family_ops); 1965 if (err) { 1966 pr_err("could not register af_vsock (%d) address family: %d\n", 1967 AF_VSOCK, err); 1968 goto err_unregister_proto; 1969 } 1970 1971 mutex_unlock(&vsock_register_mutex); 1972 return 0; 1973 1974 err_unregister_proto: 1975 proto_unregister(&vsock_proto); 1976 err_deregister_misc: 1977 misc_deregister(&vsock_device); 1978 err_reset_transport: 1979 transport_single = NULL; 1980 err_busy: 1981 mutex_unlock(&vsock_register_mutex); 1982 return err; 1983 } 1984 EXPORT_SYMBOL_GPL(__vsock_core_init); 1985 1986 void vsock_core_exit(void) 1987 { 1988 mutex_lock(&vsock_register_mutex); 1989 1990 misc_deregister(&vsock_device); 1991 sock_unregister(AF_VSOCK); 1992 proto_unregister(&vsock_proto); 1993 1994 /* We do not want the assignment below re-ordered. */ 1995 mb(); 1996 transport_single = NULL; 1997 1998 mutex_unlock(&vsock_register_mutex); 1999 } 2000 EXPORT_SYMBOL_GPL(vsock_core_exit); 2001 2002 const struct vsock_transport *vsock_core_get_transport(struct vsock_sock *vsk) 2003 { 2004 return vsk->transport; 2005 } 2006 EXPORT_SYMBOL_GPL(vsock_core_get_transport); 2007 2008 static void __exit vsock_exit(void) 2009 { 2010 /* Do nothing. This function makes this module removable. */ 2011 } 2012 2013 module_init(vsock_init_tables); 2014 module_exit(vsock_exit); 2015 2016 MODULE_AUTHOR("VMware, Inc."); 2017 MODULE_DESCRIPTION("VMware Virtual Socket Family"); 2018 MODULE_VERSION("1.0.2.0-k"); 2019 MODULE_LICENSE("GPL v2"); 2020