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) 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 transport->release(vsk); 652 653 lock_sock(sk); 654 sock_orphan(sk); 655 sk->sk_shutdown = SHUTDOWN_MASK; 656 657 while ((skb = skb_dequeue(&sk->sk_receive_queue))) 658 kfree_skb(skb); 659 660 /* Clean up any sockets that never were accepted. */ 661 while ((pending = vsock_dequeue_accept(sk)) != NULL) { 662 __vsock_release(pending); 663 sock_put(pending); 664 } 665 666 release_sock(sk); 667 sock_put(sk); 668 } 669 } 670 671 static void vsock_sk_destruct(struct sock *sk) 672 { 673 struct vsock_sock *vsk = vsock_sk(sk); 674 675 transport->destruct(vsk); 676 677 /* When clearing these addresses, there's no need to set the family and 678 * possibly register the address family with the kernel. 679 */ 680 vsock_addr_init(&vsk->local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 681 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY); 682 683 put_cred(vsk->owner); 684 } 685 686 static int vsock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 687 { 688 int err; 689 690 err = sock_queue_rcv_skb(sk, skb); 691 if (err) 692 kfree_skb(skb); 693 694 return err; 695 } 696 697 s64 vsock_stream_has_data(struct vsock_sock *vsk) 698 { 699 return transport->stream_has_data(vsk); 700 } 701 EXPORT_SYMBOL_GPL(vsock_stream_has_data); 702 703 s64 vsock_stream_has_space(struct vsock_sock *vsk) 704 { 705 return transport->stream_has_space(vsk); 706 } 707 EXPORT_SYMBOL_GPL(vsock_stream_has_space); 708 709 static int vsock_release(struct socket *sock) 710 { 711 __vsock_release(sock->sk); 712 sock->sk = NULL; 713 sock->state = SS_FREE; 714 715 return 0; 716 } 717 718 static int 719 vsock_bind(struct socket *sock, struct sockaddr *addr, int addr_len) 720 { 721 int err; 722 struct sock *sk; 723 struct sockaddr_vm *vm_addr; 724 725 sk = sock->sk; 726 727 if (vsock_addr_cast(addr, addr_len, &vm_addr) != 0) 728 return -EINVAL; 729 730 lock_sock(sk); 731 err = __vsock_bind(sk, vm_addr); 732 release_sock(sk); 733 734 return err; 735 } 736 737 static int vsock_getname(struct socket *sock, 738 struct sockaddr *addr, int peer) 739 { 740 int err; 741 struct sock *sk; 742 struct vsock_sock *vsk; 743 struct sockaddr_vm *vm_addr; 744 745 sk = sock->sk; 746 vsk = vsock_sk(sk); 747 err = 0; 748 749 lock_sock(sk); 750 751 if (peer) { 752 if (sock->state != SS_CONNECTED) { 753 err = -ENOTCONN; 754 goto out; 755 } 756 vm_addr = &vsk->remote_addr; 757 } else { 758 vm_addr = &vsk->local_addr; 759 } 760 761 if (!vm_addr) { 762 err = -EINVAL; 763 goto out; 764 } 765 766 /* sys_getsockname() and sys_getpeername() pass us a 767 * MAX_SOCK_ADDR-sized buffer and don't set addr_len. Unfortunately 768 * that macro is defined in socket.c instead of .h, so we hardcode its 769 * value here. 770 */ 771 BUILD_BUG_ON(sizeof(*vm_addr) > 128); 772 memcpy(addr, vm_addr, sizeof(*vm_addr)); 773 err = sizeof(*vm_addr); 774 775 out: 776 release_sock(sk); 777 return err; 778 } 779 780 static int vsock_shutdown(struct socket *sock, int mode) 781 { 782 int err; 783 struct sock *sk; 784 785 /* User level uses SHUT_RD (0) and SHUT_WR (1), but the kernel uses 786 * RCV_SHUTDOWN (1) and SEND_SHUTDOWN (2), so we must increment mode 787 * here like the other address families do. Note also that the 788 * increment makes SHUT_RDWR (2) into RCV_SHUTDOWN | SEND_SHUTDOWN (3), 789 * which is what we want. 790 */ 791 mode++; 792 793 if ((mode & ~SHUTDOWN_MASK) || !mode) 794 return -EINVAL; 795 796 /* If this is a STREAM socket and it is not connected then bail out 797 * immediately. If it is a DGRAM socket then we must first kick the 798 * socket so that it wakes up from any sleeping calls, for example 799 * recv(), and then afterwards return the error. 800 */ 801 802 sk = sock->sk; 803 if (sock->state == SS_UNCONNECTED) { 804 err = -ENOTCONN; 805 if (sk->sk_type == SOCK_STREAM) 806 return err; 807 } else { 808 sock->state = SS_DISCONNECTING; 809 err = 0; 810 } 811 812 /* Receive and send shutdowns are treated alike. */ 813 mode = mode & (RCV_SHUTDOWN | SEND_SHUTDOWN); 814 if (mode) { 815 lock_sock(sk); 816 sk->sk_shutdown |= mode; 817 sk->sk_state_change(sk); 818 release_sock(sk); 819 820 if (sk->sk_type == SOCK_STREAM) { 821 sock_reset_flag(sk, SOCK_DONE); 822 vsock_send_shutdown(sk, mode); 823 } 824 } 825 826 return err; 827 } 828 829 static __poll_t vsock_poll(struct file *file, struct socket *sock, 830 poll_table *wait) 831 { 832 struct sock *sk; 833 __poll_t mask; 834 struct vsock_sock *vsk; 835 836 sk = sock->sk; 837 vsk = vsock_sk(sk); 838 839 poll_wait(file, sk_sleep(sk), wait); 840 mask = 0; 841 842 if (sk->sk_err) 843 /* Signify that there has been an error on this socket. */ 844 mask |= EPOLLERR; 845 846 /* INET sockets treat local write shutdown and peer write shutdown as a 847 * case of EPOLLHUP set. 848 */ 849 if ((sk->sk_shutdown == SHUTDOWN_MASK) || 850 ((sk->sk_shutdown & SEND_SHUTDOWN) && 851 (vsk->peer_shutdown & SEND_SHUTDOWN))) { 852 mask |= EPOLLHUP; 853 } 854 855 if (sk->sk_shutdown & RCV_SHUTDOWN || 856 vsk->peer_shutdown & SEND_SHUTDOWN) { 857 mask |= EPOLLRDHUP; 858 } 859 860 if (sock->type == SOCK_DGRAM) { 861 /* For datagram sockets we can read if there is something in 862 * the queue and write as long as the socket isn't shutdown for 863 * sending. 864 */ 865 if (!skb_queue_empty(&sk->sk_receive_queue) || 866 (sk->sk_shutdown & RCV_SHUTDOWN)) { 867 mask |= EPOLLIN | EPOLLRDNORM; 868 } 869 870 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) 871 mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND; 872 873 } else if (sock->type == SOCK_STREAM) { 874 lock_sock(sk); 875 876 /* Listening sockets that have connections in their accept 877 * queue can be read. 878 */ 879 if (sk->sk_state == 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; 949 950 if (msg->msg_flags & MSG_OOB) 951 return -EOPNOTSUPP; 952 953 /* For now, MSG_DONTWAIT is always assumed... */ 954 err = 0; 955 sk = sock->sk; 956 vsk = vsock_sk(sk); 957 958 lock_sock(sk); 959 960 err = vsock_auto_bind(vsk); 961 if (err) 962 goto out; 963 964 965 /* If the provided message contains an address, use that. Otherwise 966 * fall back on the socket's remote handle (if it has been connected). 967 */ 968 if (msg->msg_name && 969 vsock_addr_cast(msg->msg_name, msg->msg_namelen, 970 &remote_addr) == 0) { 971 /* Ensure this address is of the right type and is a valid 972 * destination. 973 */ 974 975 if (remote_addr->svm_cid == VMADDR_CID_ANY) 976 remote_addr->svm_cid = transport->get_local_cid(); 977 978 if (!vsock_addr_bound(remote_addr)) { 979 err = -EINVAL; 980 goto out; 981 } 982 } else if (sock->state == SS_CONNECTED) { 983 remote_addr = &vsk->remote_addr; 984 985 if (remote_addr->svm_cid == VMADDR_CID_ANY) 986 remote_addr->svm_cid = transport->get_local_cid(); 987 988 /* XXX Should connect() or this function ensure remote_addr is 989 * bound? 990 */ 991 if (!vsock_addr_bound(&vsk->remote_addr)) { 992 err = -EINVAL; 993 goto out; 994 } 995 } else { 996 err = -EINVAL; 997 goto out; 998 } 999 1000 if (!transport->dgram_allow(remote_addr->svm_cid, 1001 remote_addr->svm_port)) { 1002 err = -EINVAL; 1003 goto out; 1004 } 1005 1006 err = transport->dgram_enqueue(vsk, remote_addr, msg, len); 1007 1008 out: 1009 release_sock(sk); 1010 return err; 1011 } 1012 1013 static int vsock_dgram_connect(struct socket *sock, 1014 struct sockaddr *addr, int addr_len, int flags) 1015 { 1016 int err; 1017 struct sock *sk; 1018 struct vsock_sock *vsk; 1019 struct sockaddr_vm *remote_addr; 1020 1021 sk = sock->sk; 1022 vsk = vsock_sk(sk); 1023 1024 err = vsock_addr_cast(addr, addr_len, &remote_addr); 1025 if (err == -EAFNOSUPPORT && remote_addr->svm_family == AF_UNSPEC) { 1026 lock_sock(sk); 1027 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, 1028 VMADDR_PORT_ANY); 1029 sock->state = SS_UNCONNECTED; 1030 release_sock(sk); 1031 return 0; 1032 } else if (err != 0) 1033 return -EINVAL; 1034 1035 lock_sock(sk); 1036 1037 err = vsock_auto_bind(vsk); 1038 if (err) 1039 goto out; 1040 1041 if (!transport->dgram_allow(remote_addr->svm_cid, 1042 remote_addr->svm_port)) { 1043 err = -EINVAL; 1044 goto out; 1045 } 1046 1047 memcpy(&vsk->remote_addr, remote_addr, sizeof(vsk->remote_addr)); 1048 sock->state = SS_CONNECTED; 1049 1050 out: 1051 release_sock(sk); 1052 return err; 1053 } 1054 1055 static int vsock_dgram_recvmsg(struct socket *sock, struct msghdr *msg, 1056 size_t len, int flags) 1057 { 1058 return transport->dgram_dequeue(vsock_sk(sock->sk), msg, len, flags); 1059 } 1060 1061 static const struct proto_ops vsock_dgram_ops = { 1062 .family = PF_VSOCK, 1063 .owner = THIS_MODULE, 1064 .release = vsock_release, 1065 .bind = vsock_bind, 1066 .connect = vsock_dgram_connect, 1067 .socketpair = sock_no_socketpair, 1068 .accept = sock_no_accept, 1069 .getname = vsock_getname, 1070 .poll = vsock_poll, 1071 .ioctl = sock_no_ioctl, 1072 .listen = sock_no_listen, 1073 .shutdown = vsock_shutdown, 1074 .setsockopt = sock_no_setsockopt, 1075 .getsockopt = sock_no_getsockopt, 1076 .sendmsg = vsock_dgram_sendmsg, 1077 .recvmsg = vsock_dgram_recvmsg, 1078 .mmap = sock_no_mmap, 1079 .sendpage = sock_no_sendpage, 1080 }; 1081 1082 static int vsock_transport_cancel_pkt(struct vsock_sock *vsk) 1083 { 1084 if (!transport->cancel_pkt) 1085 return -EOPNOTSUPP; 1086 1087 return transport->cancel_pkt(vsk); 1088 } 1089 1090 static void vsock_connect_timeout(struct work_struct *work) 1091 { 1092 struct sock *sk; 1093 struct vsock_sock *vsk; 1094 int cancel = 0; 1095 1096 vsk = container_of(work, struct vsock_sock, connect_work.work); 1097 sk = sk_vsock(vsk); 1098 1099 lock_sock(sk); 1100 if (sk->sk_state == TCP_SYN_SENT && 1101 (sk->sk_shutdown != SHUTDOWN_MASK)) { 1102 sk->sk_state = TCP_CLOSE; 1103 sk->sk_err = ETIMEDOUT; 1104 sk->sk_error_report(sk); 1105 cancel = 1; 1106 } 1107 release_sock(sk); 1108 if (cancel) 1109 vsock_transport_cancel_pkt(vsk); 1110 1111 sock_put(sk); 1112 } 1113 1114 static int vsock_stream_connect(struct socket *sock, struct sockaddr *addr, 1115 int addr_len, int flags) 1116 { 1117 int err; 1118 struct sock *sk; 1119 struct vsock_sock *vsk; 1120 struct sockaddr_vm *remote_addr; 1121 long timeout; 1122 DEFINE_WAIT(wait); 1123 1124 err = 0; 1125 sk = sock->sk; 1126 vsk = vsock_sk(sk); 1127 1128 lock_sock(sk); 1129 1130 /* XXX AF_UNSPEC should make us disconnect like AF_INET. */ 1131 switch (sock->state) { 1132 case SS_CONNECTED: 1133 err = -EISCONN; 1134 goto out; 1135 case SS_DISCONNECTING: 1136 err = -EINVAL; 1137 goto out; 1138 case SS_CONNECTING: 1139 /* This continues on so we can move sock into the SS_CONNECTED 1140 * state once the connection has completed (at which point err 1141 * will be set to zero also). Otherwise, we will either wait 1142 * for the connection or return -EALREADY should this be a 1143 * non-blocking call. 1144 */ 1145 err = -EALREADY; 1146 break; 1147 default: 1148 if ((sk->sk_state == TCP_LISTEN) || 1149 vsock_addr_cast(addr, addr_len, &remote_addr) != 0) { 1150 err = -EINVAL; 1151 goto out; 1152 } 1153 1154 /* The hypervisor and well-known contexts do not have socket 1155 * endpoints. 1156 */ 1157 if (!transport->stream_allow(remote_addr->svm_cid, 1158 remote_addr->svm_port)) { 1159 err = -ENETUNREACH; 1160 goto out; 1161 } 1162 1163 /* Set the remote address that we are connecting to. */ 1164 memcpy(&vsk->remote_addr, remote_addr, 1165 sizeof(vsk->remote_addr)); 1166 1167 err = vsock_auto_bind(vsk); 1168 if (err) 1169 goto out; 1170 1171 sk->sk_state = TCP_SYN_SENT; 1172 1173 err = transport->connect(vsk); 1174 if (err < 0) 1175 goto out; 1176 1177 /* Mark sock as connecting and set the error code to in 1178 * progress in case this is a non-blocking connect. 1179 */ 1180 sock->state = SS_CONNECTING; 1181 err = -EINPROGRESS; 1182 } 1183 1184 /* The receive path will handle all communication until we are able to 1185 * enter the connected state. Here we wait for the connection to be 1186 * completed or a notification of an error. 1187 */ 1188 timeout = vsk->connect_timeout; 1189 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1190 1191 while (sk->sk_state != TCP_ESTABLISHED && sk->sk_err == 0) { 1192 if (flags & O_NONBLOCK) { 1193 /* If we're not going to block, we schedule a timeout 1194 * function to generate a timeout on the connection 1195 * attempt, in case the peer doesn't respond in a 1196 * timely manner. We hold on to the socket until the 1197 * timeout fires. 1198 */ 1199 sock_hold(sk); 1200 schedule_delayed_work(&vsk->connect_work, timeout); 1201 1202 /* Skip ahead to preserve error code set above. */ 1203 goto out_wait; 1204 } 1205 1206 release_sock(sk); 1207 timeout = schedule_timeout(timeout); 1208 lock_sock(sk); 1209 1210 if (signal_pending(current)) { 1211 err = sock_intr_errno(timeout); 1212 sk->sk_state = TCP_CLOSE; 1213 sock->state = SS_UNCONNECTED; 1214 vsock_transport_cancel_pkt(vsk); 1215 goto out_wait; 1216 } else if (timeout == 0) { 1217 err = -ETIMEDOUT; 1218 sk->sk_state = TCP_CLOSE; 1219 sock->state = SS_UNCONNECTED; 1220 vsock_transport_cancel_pkt(vsk); 1221 goto out_wait; 1222 } 1223 1224 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1225 } 1226 1227 if (sk->sk_err) { 1228 err = -sk->sk_err; 1229 sk->sk_state = TCP_CLOSE; 1230 sock->state = SS_UNCONNECTED; 1231 } else { 1232 err = 0; 1233 } 1234 1235 out_wait: 1236 finish_wait(sk_sleep(sk), &wait); 1237 out: 1238 release_sock(sk); 1239 return err; 1240 } 1241 1242 static int vsock_accept(struct socket *sock, struct socket *newsock, int flags, 1243 bool kern) 1244 { 1245 struct sock *listener; 1246 int err; 1247 struct sock *connected; 1248 struct vsock_sock *vconnected; 1249 long timeout; 1250 DEFINE_WAIT(wait); 1251 1252 err = 0; 1253 listener = sock->sk; 1254 1255 lock_sock(listener); 1256 1257 if (sock->type != SOCK_STREAM) { 1258 err = -EOPNOTSUPP; 1259 goto out; 1260 } 1261 1262 if (listener->sk_state != TCP_LISTEN) { 1263 err = -EINVAL; 1264 goto out; 1265 } 1266 1267 /* Wait for children sockets to appear; these are the new sockets 1268 * created upon connection establishment. 1269 */ 1270 timeout = sock_sndtimeo(listener, flags & O_NONBLOCK); 1271 prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE); 1272 1273 while ((connected = vsock_dequeue_accept(listener)) == NULL && 1274 listener->sk_err == 0) { 1275 release_sock(listener); 1276 timeout = schedule_timeout(timeout); 1277 finish_wait(sk_sleep(listener), &wait); 1278 lock_sock(listener); 1279 1280 if (signal_pending(current)) { 1281 err = sock_intr_errno(timeout); 1282 goto out; 1283 } else if (timeout == 0) { 1284 err = -EAGAIN; 1285 goto out; 1286 } 1287 1288 prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE); 1289 } 1290 finish_wait(sk_sleep(listener), &wait); 1291 1292 if (listener->sk_err) 1293 err = -listener->sk_err; 1294 1295 if (connected) { 1296 listener->sk_ack_backlog--; 1297 1298 lock_sock_nested(connected, SINGLE_DEPTH_NESTING); 1299 vconnected = vsock_sk(connected); 1300 1301 /* If the listener socket has received an error, then we should 1302 * reject this socket and return. Note that we simply mark the 1303 * socket rejected, drop our reference, and let the cleanup 1304 * function handle the cleanup; the fact that we found it in 1305 * the listener's accept queue guarantees that the cleanup 1306 * function hasn't run yet. 1307 */ 1308 if (err) { 1309 vconnected->rejected = true; 1310 } else { 1311 newsock->state = SS_CONNECTED; 1312 sock_graft(connected, newsock); 1313 } 1314 1315 release_sock(connected); 1316 sock_put(connected); 1317 } 1318 1319 out: 1320 release_sock(listener); 1321 return err; 1322 } 1323 1324 static int vsock_listen(struct socket *sock, int backlog) 1325 { 1326 int err; 1327 struct sock *sk; 1328 struct vsock_sock *vsk; 1329 1330 sk = sock->sk; 1331 1332 lock_sock(sk); 1333 1334 if (sock->type != SOCK_STREAM) { 1335 err = -EOPNOTSUPP; 1336 goto out; 1337 } 1338 1339 if (sock->state != SS_UNCONNECTED) { 1340 err = -EINVAL; 1341 goto out; 1342 } 1343 1344 vsk = vsock_sk(sk); 1345 1346 if (!vsock_addr_bound(&vsk->local_addr)) { 1347 err = -EINVAL; 1348 goto out; 1349 } 1350 1351 sk->sk_max_ack_backlog = backlog; 1352 sk->sk_state = TCP_LISTEN; 1353 1354 err = 0; 1355 1356 out: 1357 release_sock(sk); 1358 return err; 1359 } 1360 1361 static int vsock_stream_setsockopt(struct socket *sock, 1362 int level, 1363 int optname, 1364 char __user *optval, 1365 unsigned int optlen) 1366 { 1367 int err; 1368 struct sock *sk; 1369 struct vsock_sock *vsk; 1370 u64 val; 1371 1372 if (level != AF_VSOCK) 1373 return -ENOPROTOOPT; 1374 1375 #define COPY_IN(_v) \ 1376 do { \ 1377 if (optlen < sizeof(_v)) { \ 1378 err = -EINVAL; \ 1379 goto exit; \ 1380 } \ 1381 if (copy_from_user(&_v, optval, sizeof(_v)) != 0) { \ 1382 err = -EFAULT; \ 1383 goto exit; \ 1384 } \ 1385 } while (0) 1386 1387 err = 0; 1388 sk = sock->sk; 1389 vsk = vsock_sk(sk); 1390 1391 lock_sock(sk); 1392 1393 switch (optname) { 1394 case SO_VM_SOCKETS_BUFFER_SIZE: 1395 COPY_IN(val); 1396 transport->set_buffer_size(vsk, val); 1397 break; 1398 1399 case SO_VM_SOCKETS_BUFFER_MAX_SIZE: 1400 COPY_IN(val); 1401 transport->set_max_buffer_size(vsk, val); 1402 break; 1403 1404 case SO_VM_SOCKETS_BUFFER_MIN_SIZE: 1405 COPY_IN(val); 1406 transport->set_min_buffer_size(vsk, val); 1407 break; 1408 1409 case SO_VM_SOCKETS_CONNECT_TIMEOUT: { 1410 struct __kernel_old_timeval tv; 1411 COPY_IN(tv); 1412 if (tv.tv_sec >= 0 && tv.tv_usec < USEC_PER_SEC && 1413 tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)) { 1414 vsk->connect_timeout = tv.tv_sec * HZ + 1415 DIV_ROUND_UP(tv.tv_usec, (1000000 / HZ)); 1416 if (vsk->connect_timeout == 0) 1417 vsk->connect_timeout = 1418 VSOCK_DEFAULT_CONNECT_TIMEOUT; 1419 1420 } else { 1421 err = -ERANGE; 1422 } 1423 break; 1424 } 1425 1426 default: 1427 err = -ENOPROTOOPT; 1428 break; 1429 } 1430 1431 #undef COPY_IN 1432 1433 exit: 1434 release_sock(sk); 1435 return err; 1436 } 1437 1438 static int vsock_stream_getsockopt(struct socket *sock, 1439 int level, int optname, 1440 char __user *optval, 1441 int __user *optlen) 1442 { 1443 int err; 1444 int len; 1445 struct sock *sk; 1446 struct vsock_sock *vsk; 1447 u64 val; 1448 1449 if (level != AF_VSOCK) 1450 return -ENOPROTOOPT; 1451 1452 err = get_user(len, optlen); 1453 if (err != 0) 1454 return err; 1455 1456 #define COPY_OUT(_v) \ 1457 do { \ 1458 if (len < sizeof(_v)) \ 1459 return -EINVAL; \ 1460 \ 1461 len = sizeof(_v); \ 1462 if (copy_to_user(optval, &_v, len) != 0) \ 1463 return -EFAULT; \ 1464 \ 1465 } while (0) 1466 1467 err = 0; 1468 sk = sock->sk; 1469 vsk = vsock_sk(sk); 1470 1471 switch (optname) { 1472 case SO_VM_SOCKETS_BUFFER_SIZE: 1473 val = transport->get_buffer_size(vsk); 1474 COPY_OUT(val); 1475 break; 1476 1477 case SO_VM_SOCKETS_BUFFER_MAX_SIZE: 1478 val = transport->get_max_buffer_size(vsk); 1479 COPY_OUT(val); 1480 break; 1481 1482 case SO_VM_SOCKETS_BUFFER_MIN_SIZE: 1483 val = transport->get_min_buffer_size(vsk); 1484 COPY_OUT(val); 1485 break; 1486 1487 case SO_VM_SOCKETS_CONNECT_TIMEOUT: { 1488 struct __kernel_old_timeval tv; 1489 tv.tv_sec = vsk->connect_timeout / HZ; 1490 tv.tv_usec = 1491 (vsk->connect_timeout - 1492 tv.tv_sec * HZ) * (1000000 / HZ); 1493 COPY_OUT(tv); 1494 break; 1495 } 1496 default: 1497 return -ENOPROTOOPT; 1498 } 1499 1500 err = put_user(len, optlen); 1501 if (err != 0) 1502 return -EFAULT; 1503 1504 #undef COPY_OUT 1505 1506 return 0; 1507 } 1508 1509 static int vsock_stream_sendmsg(struct socket *sock, struct msghdr *msg, 1510 size_t len) 1511 { 1512 struct sock *sk; 1513 struct vsock_sock *vsk; 1514 ssize_t total_written; 1515 long timeout; 1516 int err; 1517 struct vsock_transport_send_notify_data send_data; 1518 DEFINE_WAIT_FUNC(wait, woken_wake_function); 1519 1520 sk = sock->sk; 1521 vsk = vsock_sk(sk); 1522 total_written = 0; 1523 err = 0; 1524 1525 if (msg->msg_flags & MSG_OOB) 1526 return -EOPNOTSUPP; 1527 1528 lock_sock(sk); 1529 1530 /* Callers should not provide a destination with stream sockets. */ 1531 if (msg->msg_namelen) { 1532 err = sk->sk_state == TCP_ESTABLISHED ? -EISCONN : -EOPNOTSUPP; 1533 goto out; 1534 } 1535 1536 /* Send data only if both sides are not shutdown in the direction. */ 1537 if (sk->sk_shutdown & SEND_SHUTDOWN || 1538 vsk->peer_shutdown & RCV_SHUTDOWN) { 1539 err = -EPIPE; 1540 goto out; 1541 } 1542 1543 if (sk->sk_state != TCP_ESTABLISHED || 1544 !vsock_addr_bound(&vsk->local_addr)) { 1545 err = -ENOTCONN; 1546 goto out; 1547 } 1548 1549 if (!vsock_addr_bound(&vsk->remote_addr)) { 1550 err = -EDESTADDRREQ; 1551 goto out; 1552 } 1553 1554 /* Wait for room in the produce queue to enqueue our user's data. */ 1555 timeout = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT); 1556 1557 err = transport->notify_send_init(vsk, &send_data); 1558 if (err < 0) 1559 goto out; 1560 1561 while (total_written < len) { 1562 ssize_t written; 1563 1564 add_wait_queue(sk_sleep(sk), &wait); 1565 while (vsock_stream_has_space(vsk) == 0 && 1566 sk->sk_err == 0 && 1567 !(sk->sk_shutdown & SEND_SHUTDOWN) && 1568 !(vsk->peer_shutdown & RCV_SHUTDOWN)) { 1569 1570 /* Don't wait for non-blocking sockets. */ 1571 if (timeout == 0) { 1572 err = -EAGAIN; 1573 remove_wait_queue(sk_sleep(sk), &wait); 1574 goto out_err; 1575 } 1576 1577 err = transport->notify_send_pre_block(vsk, &send_data); 1578 if (err < 0) { 1579 remove_wait_queue(sk_sleep(sk), &wait); 1580 goto out_err; 1581 } 1582 1583 release_sock(sk); 1584 timeout = wait_woken(&wait, TASK_INTERRUPTIBLE, timeout); 1585 lock_sock(sk); 1586 if (signal_pending(current)) { 1587 err = sock_intr_errno(timeout); 1588 remove_wait_queue(sk_sleep(sk), &wait); 1589 goto out_err; 1590 } else if (timeout == 0) { 1591 err = -EAGAIN; 1592 remove_wait_queue(sk_sleep(sk), &wait); 1593 goto out_err; 1594 } 1595 } 1596 remove_wait_queue(sk_sleep(sk), &wait); 1597 1598 /* These checks occur both as part of and after the loop 1599 * conditional since we need to check before and after 1600 * sleeping. 1601 */ 1602 if (sk->sk_err) { 1603 err = -sk->sk_err; 1604 goto out_err; 1605 } else if ((sk->sk_shutdown & SEND_SHUTDOWN) || 1606 (vsk->peer_shutdown & RCV_SHUTDOWN)) { 1607 err = -EPIPE; 1608 goto out_err; 1609 } 1610 1611 err = transport->notify_send_pre_enqueue(vsk, &send_data); 1612 if (err < 0) 1613 goto out_err; 1614 1615 /* Note that enqueue will only write as many bytes as are free 1616 * in the produce queue, so we don't need to ensure len is 1617 * smaller than the queue size. It is the caller's 1618 * responsibility to check how many bytes we were able to send. 1619 */ 1620 1621 written = transport->stream_enqueue( 1622 vsk, msg, 1623 len - total_written); 1624 if (written < 0) { 1625 err = -ENOMEM; 1626 goto out_err; 1627 } 1628 1629 total_written += written; 1630 1631 err = transport->notify_send_post_enqueue( 1632 vsk, written, &send_data); 1633 if (err < 0) 1634 goto out_err; 1635 1636 } 1637 1638 out_err: 1639 if (total_written > 0) 1640 err = total_written; 1641 out: 1642 release_sock(sk); 1643 return err; 1644 } 1645 1646 1647 static int 1648 vsock_stream_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, 1649 int flags) 1650 { 1651 struct sock *sk; 1652 struct vsock_sock *vsk; 1653 int err; 1654 size_t target; 1655 ssize_t copied; 1656 long timeout; 1657 struct vsock_transport_recv_notify_data recv_data; 1658 1659 DEFINE_WAIT(wait); 1660 1661 sk = sock->sk; 1662 vsk = vsock_sk(sk); 1663 err = 0; 1664 1665 lock_sock(sk); 1666 1667 if (sk->sk_state != TCP_ESTABLISHED) { 1668 /* Recvmsg is supposed to return 0 if a peer performs an 1669 * orderly shutdown. Differentiate between that case and when a 1670 * peer has not connected or a local shutdown occured with the 1671 * SOCK_DONE flag. 1672 */ 1673 if (sock_flag(sk, SOCK_DONE)) 1674 err = 0; 1675 else 1676 err = -ENOTCONN; 1677 1678 goto out; 1679 } 1680 1681 if (flags & MSG_OOB) { 1682 err = -EOPNOTSUPP; 1683 goto out; 1684 } 1685 1686 /* We don't check peer_shutdown flag here since peer may actually shut 1687 * down, but there can be data in the queue that a local socket can 1688 * receive. 1689 */ 1690 if (sk->sk_shutdown & RCV_SHUTDOWN) { 1691 err = 0; 1692 goto out; 1693 } 1694 1695 /* It is valid on Linux to pass in a zero-length receive buffer. This 1696 * is not an error. We may as well bail out now. 1697 */ 1698 if (!len) { 1699 err = 0; 1700 goto out; 1701 } 1702 1703 /* We must not copy less than target bytes into the user's buffer 1704 * before returning successfully, so we wait for the consume queue to 1705 * have that much data to consume before dequeueing. Note that this 1706 * makes it impossible to handle cases where target is greater than the 1707 * queue size. 1708 */ 1709 target = sock_rcvlowat(sk, flags & MSG_WAITALL, len); 1710 if (target >= transport->stream_rcvhiwat(vsk)) { 1711 err = -ENOMEM; 1712 goto out; 1713 } 1714 timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); 1715 copied = 0; 1716 1717 err = transport->notify_recv_init(vsk, target, &recv_data); 1718 if (err < 0) 1719 goto out; 1720 1721 1722 while (1) { 1723 s64 ready; 1724 1725 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1726 ready = vsock_stream_has_data(vsk); 1727 1728 if (ready == 0) { 1729 if (sk->sk_err != 0 || 1730 (sk->sk_shutdown & RCV_SHUTDOWN) || 1731 (vsk->peer_shutdown & SEND_SHUTDOWN)) { 1732 finish_wait(sk_sleep(sk), &wait); 1733 break; 1734 } 1735 /* Don't wait for non-blocking sockets. */ 1736 if (timeout == 0) { 1737 err = -EAGAIN; 1738 finish_wait(sk_sleep(sk), &wait); 1739 break; 1740 } 1741 1742 err = transport->notify_recv_pre_block( 1743 vsk, target, &recv_data); 1744 if (err < 0) { 1745 finish_wait(sk_sleep(sk), &wait); 1746 break; 1747 } 1748 release_sock(sk); 1749 timeout = schedule_timeout(timeout); 1750 lock_sock(sk); 1751 1752 if (signal_pending(current)) { 1753 err = sock_intr_errno(timeout); 1754 finish_wait(sk_sleep(sk), &wait); 1755 break; 1756 } else if (timeout == 0) { 1757 err = -EAGAIN; 1758 finish_wait(sk_sleep(sk), &wait); 1759 break; 1760 } 1761 } else { 1762 ssize_t read; 1763 1764 finish_wait(sk_sleep(sk), &wait); 1765 1766 if (ready < 0) { 1767 /* Invalid queue pair content. XXX This should 1768 * be changed to a connection reset in a later 1769 * change. 1770 */ 1771 1772 err = -ENOMEM; 1773 goto out; 1774 } 1775 1776 err = transport->notify_recv_pre_dequeue( 1777 vsk, target, &recv_data); 1778 if (err < 0) 1779 break; 1780 1781 read = transport->stream_dequeue( 1782 vsk, msg, 1783 len - copied, flags); 1784 if (read < 0) { 1785 err = -ENOMEM; 1786 break; 1787 } 1788 1789 copied += read; 1790 1791 err = transport->notify_recv_post_dequeue( 1792 vsk, target, read, 1793 !(flags & MSG_PEEK), &recv_data); 1794 if (err < 0) 1795 goto out; 1796 1797 if (read >= target || flags & MSG_PEEK) 1798 break; 1799 1800 target -= read; 1801 } 1802 } 1803 1804 if (sk->sk_err) 1805 err = -sk->sk_err; 1806 else if (sk->sk_shutdown & RCV_SHUTDOWN) 1807 err = 0; 1808 1809 if (copied > 0) 1810 err = copied; 1811 1812 out: 1813 release_sock(sk); 1814 return err; 1815 } 1816 1817 static const struct proto_ops vsock_stream_ops = { 1818 .family = PF_VSOCK, 1819 .owner = THIS_MODULE, 1820 .release = vsock_release, 1821 .bind = vsock_bind, 1822 .connect = vsock_stream_connect, 1823 .socketpair = sock_no_socketpair, 1824 .accept = vsock_accept, 1825 .getname = vsock_getname, 1826 .poll = vsock_poll, 1827 .ioctl = sock_no_ioctl, 1828 .listen = vsock_listen, 1829 .shutdown = vsock_shutdown, 1830 .setsockopt = vsock_stream_setsockopt, 1831 .getsockopt = vsock_stream_getsockopt, 1832 .sendmsg = vsock_stream_sendmsg, 1833 .recvmsg = vsock_stream_recvmsg, 1834 .mmap = sock_no_mmap, 1835 .sendpage = sock_no_sendpage, 1836 }; 1837 1838 static int vsock_create(struct net *net, struct socket *sock, 1839 int protocol, int kern) 1840 { 1841 if (!sock) 1842 return -EINVAL; 1843 1844 if (protocol && protocol != PF_VSOCK) 1845 return -EPROTONOSUPPORT; 1846 1847 switch (sock->type) { 1848 case SOCK_DGRAM: 1849 sock->ops = &vsock_dgram_ops; 1850 break; 1851 case SOCK_STREAM: 1852 sock->ops = &vsock_stream_ops; 1853 break; 1854 default: 1855 return -ESOCKTNOSUPPORT; 1856 } 1857 1858 sock->state = SS_UNCONNECTED; 1859 1860 return __vsock_create(net, sock, NULL, GFP_KERNEL, 0, kern) ? 0 : -ENOMEM; 1861 } 1862 1863 static const struct net_proto_family vsock_family_ops = { 1864 .family = AF_VSOCK, 1865 .create = vsock_create, 1866 .owner = THIS_MODULE, 1867 }; 1868 1869 static long vsock_dev_do_ioctl(struct file *filp, 1870 unsigned int cmd, void __user *ptr) 1871 { 1872 u32 __user *p = ptr; 1873 int retval = 0; 1874 1875 switch (cmd) { 1876 case IOCTL_VM_SOCKETS_GET_LOCAL_CID: 1877 if (put_user(transport->get_local_cid(), p) != 0) 1878 retval = -EFAULT; 1879 break; 1880 1881 default: 1882 pr_err("Unknown ioctl %d\n", cmd); 1883 retval = -EINVAL; 1884 } 1885 1886 return retval; 1887 } 1888 1889 static long vsock_dev_ioctl(struct file *filp, 1890 unsigned int cmd, unsigned long arg) 1891 { 1892 return vsock_dev_do_ioctl(filp, cmd, (void __user *)arg); 1893 } 1894 1895 #ifdef CONFIG_COMPAT 1896 static long vsock_dev_compat_ioctl(struct file *filp, 1897 unsigned int cmd, unsigned long arg) 1898 { 1899 return vsock_dev_do_ioctl(filp, cmd, compat_ptr(arg)); 1900 } 1901 #endif 1902 1903 static const struct file_operations vsock_device_ops = { 1904 .owner = THIS_MODULE, 1905 .unlocked_ioctl = vsock_dev_ioctl, 1906 #ifdef CONFIG_COMPAT 1907 .compat_ioctl = vsock_dev_compat_ioctl, 1908 #endif 1909 .open = nonseekable_open, 1910 }; 1911 1912 static struct miscdevice vsock_device = { 1913 .name = "vsock", 1914 .fops = &vsock_device_ops, 1915 }; 1916 1917 int __vsock_core_init(const struct vsock_transport *t, struct module *owner) 1918 { 1919 int err = mutex_lock_interruptible(&vsock_register_mutex); 1920 1921 if (err) 1922 return err; 1923 1924 if (transport) { 1925 err = -EBUSY; 1926 goto err_busy; 1927 } 1928 1929 /* Transport must be the owner of the protocol so that it can't 1930 * unload while there are open sockets. 1931 */ 1932 vsock_proto.owner = owner; 1933 transport = t; 1934 1935 vsock_device.minor = MISC_DYNAMIC_MINOR; 1936 err = misc_register(&vsock_device); 1937 if (err) { 1938 pr_err("Failed to register misc device\n"); 1939 goto err_reset_transport; 1940 } 1941 1942 err = proto_register(&vsock_proto, 1); /* we want our slab */ 1943 if (err) { 1944 pr_err("Cannot register vsock protocol\n"); 1945 goto err_deregister_misc; 1946 } 1947 1948 err = sock_register(&vsock_family_ops); 1949 if (err) { 1950 pr_err("could not register af_vsock (%d) address family: %d\n", 1951 AF_VSOCK, err); 1952 goto err_unregister_proto; 1953 } 1954 1955 mutex_unlock(&vsock_register_mutex); 1956 return 0; 1957 1958 err_unregister_proto: 1959 proto_unregister(&vsock_proto); 1960 err_deregister_misc: 1961 misc_deregister(&vsock_device); 1962 err_reset_transport: 1963 transport = NULL; 1964 err_busy: 1965 mutex_unlock(&vsock_register_mutex); 1966 return err; 1967 } 1968 EXPORT_SYMBOL_GPL(__vsock_core_init); 1969 1970 void vsock_core_exit(void) 1971 { 1972 mutex_lock(&vsock_register_mutex); 1973 1974 misc_deregister(&vsock_device); 1975 sock_unregister(AF_VSOCK); 1976 proto_unregister(&vsock_proto); 1977 1978 /* We do not want the assignment below re-ordered. */ 1979 mb(); 1980 transport = NULL; 1981 1982 mutex_unlock(&vsock_register_mutex); 1983 } 1984 EXPORT_SYMBOL_GPL(vsock_core_exit); 1985 1986 const struct vsock_transport *vsock_core_get_transport(void) 1987 { 1988 /* vsock_register_mutex not taken since only the transport uses this 1989 * function and only while registered. 1990 */ 1991 return transport; 1992 } 1993 EXPORT_SYMBOL_GPL(vsock_core_get_transport); 1994 1995 static void __exit vsock_exit(void) 1996 { 1997 /* Do nothing. This function makes this module removable. */ 1998 } 1999 2000 module_init(vsock_init_tables); 2001 module_exit(vsock_exit); 2002 2003 MODULE_AUTHOR("VMware, Inc."); 2004 MODULE_DESCRIPTION("VMware Virtual Socket Family"); 2005 MODULE_VERSION("1.0.2.0-k"); 2006 MODULE_LICENSE("GPL v2"); 2007