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