1 /* 2 * net/tipc/socket.c: TIPC socket API 3 * 4 * Copyright (c) 2001-2007, Ericsson AB 5 * Copyright (c) 2004-2008, 2010-2011, Wind River Systems 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions are met: 10 * 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the names of the copyright holders nor the names of its 17 * contributors may be used to endorse or promote products derived from 18 * this software without specific prior written permission. 19 * 20 * Alternatively, this software may be distributed under the terms of the 21 * GNU General Public License ("GPL") version 2 as published by the Free 22 * Software Foundation. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 25 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 28 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 32 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 34 * POSSIBILITY OF SUCH DAMAGE. 35 */ 36 37 #include <net/sock.h> 38 39 #include "core.h" 40 #include "port.h" 41 42 #define SS_LISTENING -1 /* socket is listening */ 43 #define SS_READY -2 /* socket is connectionless */ 44 45 #define OVERLOAD_LIMIT_BASE 5000 46 #define CONN_TIMEOUT_DEFAULT 8000 /* default connect timeout = 8s */ 47 48 struct tipc_sock { 49 struct sock sk; 50 struct tipc_port *p; 51 struct tipc_portid peer_name; 52 long conn_timeout; 53 }; 54 55 #define tipc_sk(sk) ((struct tipc_sock *)(sk)) 56 #define tipc_sk_port(sk) ((struct tipc_port *)(tipc_sk(sk)->p)) 57 58 #define tipc_rx_ready(sock) (!skb_queue_empty(&sock->sk->sk_receive_queue) || \ 59 (sock->state == SS_DISCONNECTING)) 60 61 static int backlog_rcv(struct sock *sk, struct sk_buff *skb); 62 static u32 dispatch(struct tipc_port *tport, struct sk_buff *buf); 63 static void wakeupdispatch(struct tipc_port *tport); 64 65 static const struct proto_ops packet_ops; 66 static const struct proto_ops stream_ops; 67 static const struct proto_ops msg_ops; 68 69 static struct proto tipc_proto; 70 71 static int sockets_enabled; 72 73 static atomic_t tipc_queue_size = ATOMIC_INIT(0); 74 75 /* 76 * Revised TIPC socket locking policy: 77 * 78 * Most socket operations take the standard socket lock when they start 79 * and hold it until they finish (or until they need to sleep). Acquiring 80 * this lock grants the owner exclusive access to the fields of the socket 81 * data structures, with the exception of the backlog queue. A few socket 82 * operations can be done without taking the socket lock because they only 83 * read socket information that never changes during the life of the socket. 84 * 85 * Socket operations may acquire the lock for the associated TIPC port if they 86 * need to perform an operation on the port. If any routine needs to acquire 87 * both the socket lock and the port lock it must take the socket lock first 88 * to avoid the risk of deadlock. 89 * 90 * The dispatcher handling incoming messages cannot grab the socket lock in 91 * the standard fashion, since invoked it runs at the BH level and cannot block. 92 * Instead, it checks to see if the socket lock is currently owned by someone, 93 * and either handles the message itself or adds it to the socket's backlog 94 * queue; in the latter case the queued message is processed once the process 95 * owning the socket lock releases it. 96 * 97 * NOTE: Releasing the socket lock while an operation is sleeping overcomes 98 * the problem of a blocked socket operation preventing any other operations 99 * from occurring. However, applications must be careful if they have 100 * multiple threads trying to send (or receive) on the same socket, as these 101 * operations might interfere with each other. For example, doing a connect 102 * and a receive at the same time might allow the receive to consume the 103 * ACK message meant for the connect. While additional work could be done 104 * to try and overcome this, it doesn't seem to be worthwhile at the present. 105 * 106 * NOTE: Releasing the socket lock while an operation is sleeping also ensures 107 * that another operation that must be performed in a non-blocking manner is 108 * not delayed for very long because the lock has already been taken. 109 * 110 * NOTE: This code assumes that certain fields of a port/socket pair are 111 * constant over its lifetime; such fields can be examined without taking 112 * the socket lock and/or port lock, and do not need to be re-read even 113 * after resuming processing after waiting. These fields include: 114 * - socket type 115 * - pointer to socket sk structure (aka tipc_sock structure) 116 * - pointer to port structure 117 * - port reference 118 */ 119 120 /** 121 * advance_rx_queue - discard first buffer in socket receive queue 122 * 123 * Caller must hold socket lock 124 */ 125 126 static void advance_rx_queue(struct sock *sk) 127 { 128 buf_discard(__skb_dequeue(&sk->sk_receive_queue)); 129 atomic_dec(&tipc_queue_size); 130 } 131 132 /** 133 * discard_rx_queue - discard all buffers in socket receive queue 134 * 135 * Caller must hold socket lock 136 */ 137 138 static void discard_rx_queue(struct sock *sk) 139 { 140 struct sk_buff *buf; 141 142 while ((buf = __skb_dequeue(&sk->sk_receive_queue))) { 143 atomic_dec(&tipc_queue_size); 144 buf_discard(buf); 145 } 146 } 147 148 /** 149 * reject_rx_queue - reject all buffers in socket receive queue 150 * 151 * Caller must hold socket lock 152 */ 153 154 static void reject_rx_queue(struct sock *sk) 155 { 156 struct sk_buff *buf; 157 158 while ((buf = __skb_dequeue(&sk->sk_receive_queue))) { 159 tipc_reject_msg(buf, TIPC_ERR_NO_PORT); 160 atomic_dec(&tipc_queue_size); 161 } 162 } 163 164 /** 165 * tipc_create - create a TIPC socket 166 * @net: network namespace (must be default network) 167 * @sock: pre-allocated socket structure 168 * @protocol: protocol indicator (must be 0) 169 * @kern: caused by kernel or by userspace? 170 * 171 * This routine creates additional data structures used by the TIPC socket, 172 * initializes them, and links them together. 173 * 174 * Returns 0 on success, errno otherwise 175 */ 176 177 static int tipc_create(struct net *net, struct socket *sock, int protocol, 178 int kern) 179 { 180 const struct proto_ops *ops; 181 socket_state state; 182 struct sock *sk; 183 struct tipc_port *tp_ptr; 184 185 /* Validate arguments */ 186 187 if (!net_eq(net, &init_net)) 188 return -EAFNOSUPPORT; 189 190 if (unlikely(protocol != 0)) 191 return -EPROTONOSUPPORT; 192 193 switch (sock->type) { 194 case SOCK_STREAM: 195 ops = &stream_ops; 196 state = SS_UNCONNECTED; 197 break; 198 case SOCK_SEQPACKET: 199 ops = &packet_ops; 200 state = SS_UNCONNECTED; 201 break; 202 case SOCK_DGRAM: 203 case SOCK_RDM: 204 ops = &msg_ops; 205 state = SS_READY; 206 break; 207 default: 208 return -EPROTOTYPE; 209 } 210 211 /* Allocate socket's protocol area */ 212 213 sk = sk_alloc(net, AF_TIPC, GFP_KERNEL, &tipc_proto); 214 if (sk == NULL) 215 return -ENOMEM; 216 217 /* Allocate TIPC port for socket to use */ 218 219 tp_ptr = tipc_createport_raw(sk, &dispatch, &wakeupdispatch, 220 TIPC_LOW_IMPORTANCE); 221 if (unlikely(!tp_ptr)) { 222 sk_free(sk); 223 return -ENOMEM; 224 } 225 226 /* Finish initializing socket data structures */ 227 228 sock->ops = ops; 229 sock->state = state; 230 231 sock_init_data(sock, sk); 232 sk->sk_backlog_rcv = backlog_rcv; 233 tipc_sk(sk)->p = tp_ptr; 234 tipc_sk(sk)->conn_timeout = msecs_to_jiffies(CONN_TIMEOUT_DEFAULT); 235 236 spin_unlock_bh(tp_ptr->lock); 237 238 if (sock->state == SS_READY) { 239 tipc_set_portunreturnable(tp_ptr->ref, 1); 240 if (sock->type == SOCK_DGRAM) 241 tipc_set_portunreliable(tp_ptr->ref, 1); 242 } 243 244 return 0; 245 } 246 247 /** 248 * release - destroy a TIPC socket 249 * @sock: socket to destroy 250 * 251 * This routine cleans up any messages that are still queued on the socket. 252 * For DGRAM and RDM socket types, all queued messages are rejected. 253 * For SEQPACKET and STREAM socket types, the first message is rejected 254 * and any others are discarded. (If the first message on a STREAM socket 255 * is partially-read, it is discarded and the next one is rejected instead.) 256 * 257 * NOTE: Rejected messages are not necessarily returned to the sender! They 258 * are returned or discarded according to the "destination droppable" setting 259 * specified for the message by the sender. 260 * 261 * Returns 0 on success, errno otherwise 262 */ 263 264 static int release(struct socket *sock) 265 { 266 struct sock *sk = sock->sk; 267 struct tipc_port *tport; 268 struct sk_buff *buf; 269 int res; 270 271 /* 272 * Exit if socket isn't fully initialized (occurs when a failed accept() 273 * releases a pre-allocated child socket that was never used) 274 */ 275 276 if (sk == NULL) 277 return 0; 278 279 tport = tipc_sk_port(sk); 280 lock_sock(sk); 281 282 /* 283 * Reject all unreceived messages, except on an active connection 284 * (which disconnects locally & sends a 'FIN+' to peer) 285 */ 286 287 while (sock->state != SS_DISCONNECTING) { 288 buf = __skb_dequeue(&sk->sk_receive_queue); 289 if (buf == NULL) 290 break; 291 atomic_dec(&tipc_queue_size); 292 if (TIPC_SKB_CB(buf)->handle != 0) 293 buf_discard(buf); 294 else { 295 if ((sock->state == SS_CONNECTING) || 296 (sock->state == SS_CONNECTED)) { 297 sock->state = SS_DISCONNECTING; 298 tipc_disconnect(tport->ref); 299 } 300 tipc_reject_msg(buf, TIPC_ERR_NO_PORT); 301 } 302 } 303 304 /* 305 * Delete TIPC port; this ensures no more messages are queued 306 * (also disconnects an active connection & sends a 'FIN-' to peer) 307 */ 308 309 res = tipc_deleteport(tport->ref); 310 311 /* Discard any remaining (connection-based) messages in receive queue */ 312 313 discard_rx_queue(sk); 314 315 /* Reject any messages that accumulated in backlog queue */ 316 317 sock->state = SS_DISCONNECTING; 318 release_sock(sk); 319 320 sock_put(sk); 321 sock->sk = NULL; 322 323 return res; 324 } 325 326 /** 327 * bind - associate or disassocate TIPC name(s) with a socket 328 * @sock: socket structure 329 * @uaddr: socket address describing name(s) and desired operation 330 * @uaddr_len: size of socket address data structure 331 * 332 * Name and name sequence binding is indicated using a positive scope value; 333 * a negative scope value unbinds the specified name. Specifying no name 334 * (i.e. a socket address length of 0) unbinds all names from the socket. 335 * 336 * Returns 0 on success, errno otherwise 337 * 338 * NOTE: This routine doesn't need to take the socket lock since it doesn't 339 * access any non-constant socket information. 340 */ 341 342 static int bind(struct socket *sock, struct sockaddr *uaddr, int uaddr_len) 343 { 344 struct sockaddr_tipc *addr = (struct sockaddr_tipc *)uaddr; 345 u32 portref = tipc_sk_port(sock->sk)->ref; 346 347 if (unlikely(!uaddr_len)) 348 return tipc_withdraw(portref, 0, NULL); 349 350 if (uaddr_len < sizeof(struct sockaddr_tipc)) 351 return -EINVAL; 352 if (addr->family != AF_TIPC) 353 return -EAFNOSUPPORT; 354 355 if (addr->addrtype == TIPC_ADDR_NAME) 356 addr->addr.nameseq.upper = addr->addr.nameseq.lower; 357 else if (addr->addrtype != TIPC_ADDR_NAMESEQ) 358 return -EAFNOSUPPORT; 359 360 return (addr->scope > 0) ? 361 tipc_publish(portref, addr->scope, &addr->addr.nameseq) : 362 tipc_withdraw(portref, -addr->scope, &addr->addr.nameseq); 363 } 364 365 /** 366 * get_name - get port ID of socket or peer socket 367 * @sock: socket structure 368 * @uaddr: area for returned socket address 369 * @uaddr_len: area for returned length of socket address 370 * @peer: 0 = own ID, 1 = current peer ID, 2 = current/former peer ID 371 * 372 * Returns 0 on success, errno otherwise 373 * 374 * NOTE: This routine doesn't need to take the socket lock since it only 375 * accesses socket information that is unchanging (or which changes in 376 * a completely predictable manner). 377 */ 378 379 static int get_name(struct socket *sock, struct sockaddr *uaddr, 380 int *uaddr_len, int peer) 381 { 382 struct sockaddr_tipc *addr = (struct sockaddr_tipc *)uaddr; 383 struct tipc_sock *tsock = tipc_sk(sock->sk); 384 385 memset(addr, 0, sizeof(*addr)); 386 if (peer) { 387 if ((sock->state != SS_CONNECTED) && 388 ((peer != 2) || (sock->state != SS_DISCONNECTING))) 389 return -ENOTCONN; 390 addr->addr.id.ref = tsock->peer_name.ref; 391 addr->addr.id.node = tsock->peer_name.node; 392 } else { 393 addr->addr.id.ref = tsock->p->ref; 394 addr->addr.id.node = tipc_own_addr; 395 } 396 397 *uaddr_len = sizeof(*addr); 398 addr->addrtype = TIPC_ADDR_ID; 399 addr->family = AF_TIPC; 400 addr->scope = 0; 401 addr->addr.name.domain = 0; 402 403 return 0; 404 } 405 406 /** 407 * poll - read and possibly block on pollmask 408 * @file: file structure associated with the socket 409 * @sock: socket for which to calculate the poll bits 410 * @wait: ??? 411 * 412 * Returns pollmask value 413 * 414 * COMMENTARY: 415 * It appears that the usual socket locking mechanisms are not useful here 416 * since the pollmask info is potentially out-of-date the moment this routine 417 * exits. TCP and other protocols seem to rely on higher level poll routines 418 * to handle any preventable race conditions, so TIPC will do the same ... 419 * 420 * TIPC sets the returned events as follows: 421 * 422 * socket state flags set 423 * ------------ --------- 424 * unconnected no read flags 425 * no write flags 426 * 427 * connecting POLLIN/POLLRDNORM if ACK/NACK in rx queue 428 * no write flags 429 * 430 * connected POLLIN/POLLRDNORM if data in rx queue 431 * POLLOUT if port is not congested 432 * 433 * disconnecting POLLIN/POLLRDNORM/POLLHUP 434 * no write flags 435 * 436 * listening POLLIN if SYN in rx queue 437 * no write flags 438 * 439 * ready POLLIN/POLLRDNORM if data in rx queue 440 * [connectionless] POLLOUT (since port cannot be congested) 441 * 442 * IMPORTANT: The fact that a read or write operation is indicated does NOT 443 * imply that the operation will succeed, merely that it should be performed 444 * and will not block. 445 */ 446 447 static unsigned int poll(struct file *file, struct socket *sock, 448 poll_table *wait) 449 { 450 struct sock *sk = sock->sk; 451 u32 mask = 0; 452 453 poll_wait(file, sk_sleep(sk), wait); 454 455 switch ((int)sock->state) { 456 case SS_READY: 457 case SS_CONNECTED: 458 if (!tipc_sk_port(sk)->congested) 459 mask |= POLLOUT; 460 /* fall thru' */ 461 case SS_CONNECTING: 462 case SS_LISTENING: 463 if (!skb_queue_empty(&sk->sk_receive_queue)) 464 mask |= (POLLIN | POLLRDNORM); 465 break; 466 case SS_DISCONNECTING: 467 mask = (POLLIN | POLLRDNORM | POLLHUP); 468 break; 469 } 470 471 return mask; 472 } 473 474 /** 475 * dest_name_check - verify user is permitted to send to specified port name 476 * @dest: destination address 477 * @m: descriptor for message to be sent 478 * 479 * Prevents restricted configuration commands from being issued by 480 * unauthorized users. 481 * 482 * Returns 0 if permission is granted, otherwise errno 483 */ 484 485 static int dest_name_check(struct sockaddr_tipc *dest, struct msghdr *m) 486 { 487 struct tipc_cfg_msg_hdr hdr; 488 489 if (likely(dest->addr.name.name.type >= TIPC_RESERVED_TYPES)) 490 return 0; 491 if (likely(dest->addr.name.name.type == TIPC_TOP_SRV)) 492 return 0; 493 if (likely(dest->addr.name.name.type != TIPC_CFG_SRV)) 494 return -EACCES; 495 496 if (!m->msg_iovlen || (m->msg_iov[0].iov_len < sizeof(hdr))) 497 return -EMSGSIZE; 498 if (copy_from_user(&hdr, m->msg_iov[0].iov_base, sizeof(hdr))) 499 return -EFAULT; 500 if ((ntohs(hdr.tcm_type) & 0xC000) && (!capable(CAP_NET_ADMIN))) 501 return -EACCES; 502 503 return 0; 504 } 505 506 /** 507 * send_msg - send message in connectionless manner 508 * @iocb: if NULL, indicates that socket lock is already held 509 * @sock: socket structure 510 * @m: message to send 511 * @total_len: length of message 512 * 513 * Message must have an destination specified explicitly. 514 * Used for SOCK_RDM and SOCK_DGRAM messages, 515 * and for 'SYN' messages on SOCK_SEQPACKET and SOCK_STREAM connections. 516 * (Note: 'SYN+' is prohibited on SOCK_STREAM.) 517 * 518 * Returns the number of bytes sent on success, or errno otherwise 519 */ 520 521 static int send_msg(struct kiocb *iocb, struct socket *sock, 522 struct msghdr *m, size_t total_len) 523 { 524 struct sock *sk = sock->sk; 525 struct tipc_port *tport = tipc_sk_port(sk); 526 struct sockaddr_tipc *dest = (struct sockaddr_tipc *)m->msg_name; 527 int needs_conn; 528 int res = -EINVAL; 529 530 if (unlikely(!dest)) 531 return -EDESTADDRREQ; 532 if (unlikely((m->msg_namelen < sizeof(*dest)) || 533 (dest->family != AF_TIPC))) 534 return -EINVAL; 535 if ((total_len > TIPC_MAX_USER_MSG_SIZE) || 536 (m->msg_iovlen > (unsigned)INT_MAX)) 537 return -EMSGSIZE; 538 539 if (iocb) 540 lock_sock(sk); 541 542 needs_conn = (sock->state != SS_READY); 543 if (unlikely(needs_conn)) { 544 if (sock->state == SS_LISTENING) { 545 res = -EPIPE; 546 goto exit; 547 } 548 if (sock->state != SS_UNCONNECTED) { 549 res = -EISCONN; 550 goto exit; 551 } 552 if ((tport->published) || 553 ((sock->type == SOCK_STREAM) && (total_len != 0))) { 554 res = -EOPNOTSUPP; 555 goto exit; 556 } 557 if (dest->addrtype == TIPC_ADDR_NAME) { 558 tport->conn_type = dest->addr.name.name.type; 559 tport->conn_instance = dest->addr.name.name.instance; 560 } 561 562 /* Abort any pending connection attempts (very unlikely) */ 563 564 reject_rx_queue(sk); 565 } 566 567 do { 568 if (dest->addrtype == TIPC_ADDR_NAME) { 569 res = dest_name_check(dest, m); 570 if (res) 571 break; 572 res = tipc_send2name(tport->ref, 573 &dest->addr.name.name, 574 dest->addr.name.domain, 575 m->msg_iovlen, 576 m->msg_iov, 577 total_len); 578 } else if (dest->addrtype == TIPC_ADDR_ID) { 579 res = tipc_send2port(tport->ref, 580 &dest->addr.id, 581 m->msg_iovlen, 582 m->msg_iov, 583 total_len); 584 } else if (dest->addrtype == TIPC_ADDR_MCAST) { 585 if (needs_conn) { 586 res = -EOPNOTSUPP; 587 break; 588 } 589 res = dest_name_check(dest, m); 590 if (res) 591 break; 592 res = tipc_multicast(tport->ref, 593 &dest->addr.nameseq, 594 m->msg_iovlen, 595 m->msg_iov, 596 total_len); 597 } 598 if (likely(res != -ELINKCONG)) { 599 if (needs_conn && (res >= 0)) 600 sock->state = SS_CONNECTING; 601 break; 602 } 603 if (m->msg_flags & MSG_DONTWAIT) { 604 res = -EWOULDBLOCK; 605 break; 606 } 607 release_sock(sk); 608 res = wait_event_interruptible(*sk_sleep(sk), 609 !tport->congested); 610 lock_sock(sk); 611 if (res) 612 break; 613 } while (1); 614 615 exit: 616 if (iocb) 617 release_sock(sk); 618 return res; 619 } 620 621 /** 622 * send_packet - send a connection-oriented message 623 * @iocb: if NULL, indicates that socket lock is already held 624 * @sock: socket structure 625 * @m: message to send 626 * @total_len: length of message 627 * 628 * Used for SOCK_SEQPACKET messages and SOCK_STREAM data. 629 * 630 * Returns the number of bytes sent on success, or errno otherwise 631 */ 632 633 static int send_packet(struct kiocb *iocb, struct socket *sock, 634 struct msghdr *m, size_t total_len) 635 { 636 struct sock *sk = sock->sk; 637 struct tipc_port *tport = tipc_sk_port(sk); 638 struct sockaddr_tipc *dest = (struct sockaddr_tipc *)m->msg_name; 639 int res; 640 641 /* Handle implied connection establishment */ 642 643 if (unlikely(dest)) 644 return send_msg(iocb, sock, m, total_len); 645 646 if ((total_len > TIPC_MAX_USER_MSG_SIZE) || 647 (m->msg_iovlen > (unsigned)INT_MAX)) 648 return -EMSGSIZE; 649 650 if (iocb) 651 lock_sock(sk); 652 653 do { 654 if (unlikely(sock->state != SS_CONNECTED)) { 655 if (sock->state == SS_DISCONNECTING) 656 res = -EPIPE; 657 else 658 res = -ENOTCONN; 659 break; 660 } 661 662 res = tipc_send(tport->ref, m->msg_iovlen, m->msg_iov, 663 total_len); 664 if (likely(res != -ELINKCONG)) 665 break; 666 if (m->msg_flags & MSG_DONTWAIT) { 667 res = -EWOULDBLOCK; 668 break; 669 } 670 release_sock(sk); 671 res = wait_event_interruptible(*sk_sleep(sk), 672 (!tport->congested || !tport->connected)); 673 lock_sock(sk); 674 if (res) 675 break; 676 } while (1); 677 678 if (iocb) 679 release_sock(sk); 680 return res; 681 } 682 683 /** 684 * send_stream - send stream-oriented data 685 * @iocb: (unused) 686 * @sock: socket structure 687 * @m: data to send 688 * @total_len: total length of data to be sent 689 * 690 * Used for SOCK_STREAM data. 691 * 692 * Returns the number of bytes sent on success (or partial success), 693 * or errno if no data sent 694 */ 695 696 static int send_stream(struct kiocb *iocb, struct socket *sock, 697 struct msghdr *m, size_t total_len) 698 { 699 struct sock *sk = sock->sk; 700 struct tipc_port *tport = tipc_sk_port(sk); 701 struct msghdr my_msg; 702 struct iovec my_iov; 703 struct iovec *curr_iov; 704 int curr_iovlen; 705 char __user *curr_start; 706 u32 hdr_size; 707 int curr_left; 708 int bytes_to_send; 709 int bytes_sent; 710 int res; 711 712 lock_sock(sk); 713 714 /* Handle special cases where there is no connection */ 715 716 if (unlikely(sock->state != SS_CONNECTED)) { 717 if (sock->state == SS_UNCONNECTED) { 718 res = send_packet(NULL, sock, m, total_len); 719 goto exit; 720 } else if (sock->state == SS_DISCONNECTING) { 721 res = -EPIPE; 722 goto exit; 723 } else { 724 res = -ENOTCONN; 725 goto exit; 726 } 727 } 728 729 if (unlikely(m->msg_name)) { 730 res = -EISCONN; 731 goto exit; 732 } 733 734 if ((total_len > (unsigned)INT_MAX) || 735 (m->msg_iovlen > (unsigned)INT_MAX)) { 736 res = -EMSGSIZE; 737 goto exit; 738 } 739 740 /* 741 * Send each iovec entry using one or more messages 742 * 743 * Note: This algorithm is good for the most likely case 744 * (i.e. one large iovec entry), but could be improved to pass sets 745 * of small iovec entries into send_packet(). 746 */ 747 748 curr_iov = m->msg_iov; 749 curr_iovlen = m->msg_iovlen; 750 my_msg.msg_iov = &my_iov; 751 my_msg.msg_iovlen = 1; 752 my_msg.msg_flags = m->msg_flags; 753 my_msg.msg_name = NULL; 754 bytes_sent = 0; 755 756 hdr_size = msg_hdr_sz(&tport->phdr); 757 758 while (curr_iovlen--) { 759 curr_start = curr_iov->iov_base; 760 curr_left = curr_iov->iov_len; 761 762 while (curr_left) { 763 bytes_to_send = tport->max_pkt - hdr_size; 764 if (bytes_to_send > TIPC_MAX_USER_MSG_SIZE) 765 bytes_to_send = TIPC_MAX_USER_MSG_SIZE; 766 if (curr_left < bytes_to_send) 767 bytes_to_send = curr_left; 768 my_iov.iov_base = curr_start; 769 my_iov.iov_len = bytes_to_send; 770 res = send_packet(NULL, sock, &my_msg, bytes_to_send); 771 if (res < 0) { 772 if (bytes_sent) 773 res = bytes_sent; 774 goto exit; 775 } 776 curr_left -= bytes_to_send; 777 curr_start += bytes_to_send; 778 bytes_sent += bytes_to_send; 779 } 780 781 curr_iov++; 782 } 783 res = bytes_sent; 784 exit: 785 release_sock(sk); 786 return res; 787 } 788 789 /** 790 * auto_connect - complete connection setup to a remote port 791 * @sock: socket structure 792 * @msg: peer's response message 793 * 794 * Returns 0 on success, errno otherwise 795 */ 796 797 static int auto_connect(struct socket *sock, struct tipc_msg *msg) 798 { 799 struct tipc_sock *tsock = tipc_sk(sock->sk); 800 801 if (msg_errcode(msg)) { 802 sock->state = SS_DISCONNECTING; 803 return -ECONNREFUSED; 804 } 805 806 tsock->peer_name.ref = msg_origport(msg); 807 tsock->peer_name.node = msg_orignode(msg); 808 tipc_connect2port(tsock->p->ref, &tsock->peer_name); 809 tipc_set_portimportance(tsock->p->ref, msg_importance(msg)); 810 sock->state = SS_CONNECTED; 811 return 0; 812 } 813 814 /** 815 * set_orig_addr - capture sender's address for received message 816 * @m: descriptor for message info 817 * @msg: received message header 818 * 819 * Note: Address is not captured if not requested by receiver. 820 */ 821 822 static void set_orig_addr(struct msghdr *m, struct tipc_msg *msg) 823 { 824 struct sockaddr_tipc *addr = (struct sockaddr_tipc *)m->msg_name; 825 826 if (addr) { 827 addr->family = AF_TIPC; 828 addr->addrtype = TIPC_ADDR_ID; 829 addr->addr.id.ref = msg_origport(msg); 830 addr->addr.id.node = msg_orignode(msg); 831 addr->addr.name.domain = 0; /* could leave uninitialized */ 832 addr->scope = 0; /* could leave uninitialized */ 833 m->msg_namelen = sizeof(struct sockaddr_tipc); 834 } 835 } 836 837 /** 838 * anc_data_recv - optionally capture ancillary data for received message 839 * @m: descriptor for message info 840 * @msg: received message header 841 * @tport: TIPC port associated with message 842 * 843 * Note: Ancillary data is not captured if not requested by receiver. 844 * 845 * Returns 0 if successful, otherwise errno 846 */ 847 848 static int anc_data_recv(struct msghdr *m, struct tipc_msg *msg, 849 struct tipc_port *tport) 850 { 851 u32 anc_data[3]; 852 u32 err; 853 u32 dest_type; 854 int has_name; 855 int res; 856 857 if (likely(m->msg_controllen == 0)) 858 return 0; 859 860 /* Optionally capture errored message object(s) */ 861 862 err = msg ? msg_errcode(msg) : 0; 863 if (unlikely(err)) { 864 anc_data[0] = err; 865 anc_data[1] = msg_data_sz(msg); 866 res = put_cmsg(m, SOL_TIPC, TIPC_ERRINFO, 8, anc_data); 867 if (res) 868 return res; 869 if (anc_data[1]) { 870 res = put_cmsg(m, SOL_TIPC, TIPC_RETDATA, anc_data[1], 871 msg_data(msg)); 872 if (res) 873 return res; 874 } 875 } 876 877 /* Optionally capture message destination object */ 878 879 dest_type = msg ? msg_type(msg) : TIPC_DIRECT_MSG; 880 switch (dest_type) { 881 case TIPC_NAMED_MSG: 882 has_name = 1; 883 anc_data[0] = msg_nametype(msg); 884 anc_data[1] = msg_namelower(msg); 885 anc_data[2] = msg_namelower(msg); 886 break; 887 case TIPC_MCAST_MSG: 888 has_name = 1; 889 anc_data[0] = msg_nametype(msg); 890 anc_data[1] = msg_namelower(msg); 891 anc_data[2] = msg_nameupper(msg); 892 break; 893 case TIPC_CONN_MSG: 894 has_name = (tport->conn_type != 0); 895 anc_data[0] = tport->conn_type; 896 anc_data[1] = tport->conn_instance; 897 anc_data[2] = tport->conn_instance; 898 break; 899 default: 900 has_name = 0; 901 } 902 if (has_name) { 903 res = put_cmsg(m, SOL_TIPC, TIPC_DESTNAME, 12, anc_data); 904 if (res) 905 return res; 906 } 907 908 return 0; 909 } 910 911 /** 912 * recv_msg - receive packet-oriented message 913 * @iocb: (unused) 914 * @m: descriptor for message info 915 * @buf_len: total size of user buffer area 916 * @flags: receive flags 917 * 918 * Used for SOCK_DGRAM, SOCK_RDM, and SOCK_SEQPACKET messages. 919 * If the complete message doesn't fit in user area, truncate it. 920 * 921 * Returns size of returned message data, errno otherwise 922 */ 923 924 static int recv_msg(struct kiocb *iocb, struct socket *sock, 925 struct msghdr *m, size_t buf_len, int flags) 926 { 927 struct sock *sk = sock->sk; 928 struct tipc_port *tport = tipc_sk_port(sk); 929 struct sk_buff *buf; 930 struct tipc_msg *msg; 931 long timeout; 932 unsigned int sz; 933 u32 err; 934 int res; 935 936 /* Catch invalid receive requests */ 937 938 if (unlikely(!buf_len)) 939 return -EINVAL; 940 941 lock_sock(sk); 942 943 if (unlikely(sock->state == SS_UNCONNECTED)) { 944 res = -ENOTCONN; 945 goto exit; 946 } 947 948 timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); 949 restart: 950 951 /* Look for a message in receive queue; wait if necessary */ 952 953 while (skb_queue_empty(&sk->sk_receive_queue)) { 954 if (sock->state == SS_DISCONNECTING) { 955 res = -ENOTCONN; 956 goto exit; 957 } 958 if (timeout <= 0L) { 959 res = timeout ? timeout : -EWOULDBLOCK; 960 goto exit; 961 } 962 release_sock(sk); 963 timeout = wait_event_interruptible_timeout(*sk_sleep(sk), 964 tipc_rx_ready(sock), 965 timeout); 966 lock_sock(sk); 967 } 968 969 /* Look at first message in receive queue */ 970 971 buf = skb_peek(&sk->sk_receive_queue); 972 msg = buf_msg(buf); 973 sz = msg_data_sz(msg); 974 err = msg_errcode(msg); 975 976 /* Complete connection setup for an implied connect */ 977 978 if (unlikely(sock->state == SS_CONNECTING)) { 979 res = auto_connect(sock, msg); 980 if (res) 981 goto exit; 982 } 983 984 /* Discard an empty non-errored message & try again */ 985 986 if ((!sz) && (!err)) { 987 advance_rx_queue(sk); 988 goto restart; 989 } 990 991 /* Capture sender's address (optional) */ 992 993 set_orig_addr(m, msg); 994 995 /* Capture ancillary data (optional) */ 996 997 res = anc_data_recv(m, msg, tport); 998 if (res) 999 goto exit; 1000 1001 /* Capture message data (if valid) & compute return value (always) */ 1002 1003 if (!err) { 1004 if (unlikely(buf_len < sz)) { 1005 sz = buf_len; 1006 m->msg_flags |= MSG_TRUNC; 1007 } 1008 res = skb_copy_datagram_iovec(buf, msg_hdr_sz(msg), 1009 m->msg_iov, sz); 1010 if (res) 1011 goto exit; 1012 res = sz; 1013 } else { 1014 if ((sock->state == SS_READY) || 1015 ((err == TIPC_CONN_SHUTDOWN) || m->msg_control)) 1016 res = 0; 1017 else 1018 res = -ECONNRESET; 1019 } 1020 1021 /* Consume received message (optional) */ 1022 1023 if (likely(!(flags & MSG_PEEK))) { 1024 if ((sock->state != SS_READY) && 1025 (++tport->conn_unacked >= TIPC_FLOW_CONTROL_WIN)) 1026 tipc_acknowledge(tport->ref, tport->conn_unacked); 1027 advance_rx_queue(sk); 1028 } 1029 exit: 1030 release_sock(sk); 1031 return res; 1032 } 1033 1034 /** 1035 * recv_stream - receive stream-oriented data 1036 * @iocb: (unused) 1037 * @m: descriptor for message info 1038 * @buf_len: total size of user buffer area 1039 * @flags: receive flags 1040 * 1041 * Used for SOCK_STREAM messages only. If not enough data is available 1042 * will optionally wait for more; never truncates data. 1043 * 1044 * Returns size of returned message data, errno otherwise 1045 */ 1046 1047 static int recv_stream(struct kiocb *iocb, struct socket *sock, 1048 struct msghdr *m, size_t buf_len, int flags) 1049 { 1050 struct sock *sk = sock->sk; 1051 struct tipc_port *tport = tipc_sk_port(sk); 1052 struct sk_buff *buf; 1053 struct tipc_msg *msg; 1054 long timeout; 1055 unsigned int sz; 1056 int sz_to_copy, target, needed; 1057 int sz_copied = 0; 1058 u32 err; 1059 int res = 0; 1060 1061 /* Catch invalid receive attempts */ 1062 1063 if (unlikely(!buf_len)) 1064 return -EINVAL; 1065 1066 lock_sock(sk); 1067 1068 if (unlikely((sock->state == SS_UNCONNECTED) || 1069 (sock->state == SS_CONNECTING))) { 1070 res = -ENOTCONN; 1071 goto exit; 1072 } 1073 1074 target = sock_rcvlowat(sk, flags & MSG_WAITALL, buf_len); 1075 timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); 1076 restart: 1077 1078 /* Look for a message in receive queue; wait if necessary */ 1079 1080 while (skb_queue_empty(&sk->sk_receive_queue)) { 1081 if (sock->state == SS_DISCONNECTING) { 1082 res = -ENOTCONN; 1083 goto exit; 1084 } 1085 if (timeout <= 0L) { 1086 res = timeout ? timeout : -EWOULDBLOCK; 1087 goto exit; 1088 } 1089 release_sock(sk); 1090 timeout = wait_event_interruptible_timeout(*sk_sleep(sk), 1091 tipc_rx_ready(sock), 1092 timeout); 1093 lock_sock(sk); 1094 } 1095 1096 /* Look at first message in receive queue */ 1097 1098 buf = skb_peek(&sk->sk_receive_queue); 1099 msg = buf_msg(buf); 1100 sz = msg_data_sz(msg); 1101 err = msg_errcode(msg); 1102 1103 /* Discard an empty non-errored message & try again */ 1104 1105 if ((!sz) && (!err)) { 1106 advance_rx_queue(sk); 1107 goto restart; 1108 } 1109 1110 /* Optionally capture sender's address & ancillary data of first msg */ 1111 1112 if (sz_copied == 0) { 1113 set_orig_addr(m, msg); 1114 res = anc_data_recv(m, msg, tport); 1115 if (res) 1116 goto exit; 1117 } 1118 1119 /* Capture message data (if valid) & compute return value (always) */ 1120 1121 if (!err) { 1122 u32 offset = (u32)(unsigned long)(TIPC_SKB_CB(buf)->handle); 1123 1124 sz -= offset; 1125 needed = (buf_len - sz_copied); 1126 sz_to_copy = (sz <= needed) ? sz : needed; 1127 1128 res = skb_copy_datagram_iovec(buf, msg_hdr_sz(msg) + offset, 1129 m->msg_iov, sz_to_copy); 1130 if (res) 1131 goto exit; 1132 1133 sz_copied += sz_to_copy; 1134 1135 if (sz_to_copy < sz) { 1136 if (!(flags & MSG_PEEK)) 1137 TIPC_SKB_CB(buf)->handle = 1138 (void *)(unsigned long)(offset + sz_to_copy); 1139 goto exit; 1140 } 1141 } else { 1142 if (sz_copied != 0) 1143 goto exit; /* can't add error msg to valid data */ 1144 1145 if ((err == TIPC_CONN_SHUTDOWN) || m->msg_control) 1146 res = 0; 1147 else 1148 res = -ECONNRESET; 1149 } 1150 1151 /* Consume received message (optional) */ 1152 1153 if (likely(!(flags & MSG_PEEK))) { 1154 if (unlikely(++tport->conn_unacked >= TIPC_FLOW_CONTROL_WIN)) 1155 tipc_acknowledge(tport->ref, tport->conn_unacked); 1156 advance_rx_queue(sk); 1157 } 1158 1159 /* Loop around if more data is required */ 1160 1161 if ((sz_copied < buf_len) && /* didn't get all requested data */ 1162 (!skb_queue_empty(&sk->sk_receive_queue) || 1163 (sz_copied < target)) && /* and more is ready or required */ 1164 (!(flags & MSG_PEEK)) && /* and aren't just peeking at data */ 1165 (!err)) /* and haven't reached a FIN */ 1166 goto restart; 1167 1168 exit: 1169 release_sock(sk); 1170 return sz_copied ? sz_copied : res; 1171 } 1172 1173 /** 1174 * rx_queue_full - determine if receive queue can accept another message 1175 * @msg: message to be added to queue 1176 * @queue_size: current size of queue 1177 * @base: nominal maximum size of queue 1178 * 1179 * Returns 1 if queue is unable to accept message, 0 otherwise 1180 */ 1181 1182 static int rx_queue_full(struct tipc_msg *msg, u32 queue_size, u32 base) 1183 { 1184 u32 threshold; 1185 u32 imp = msg_importance(msg); 1186 1187 if (imp == TIPC_LOW_IMPORTANCE) 1188 threshold = base; 1189 else if (imp == TIPC_MEDIUM_IMPORTANCE) 1190 threshold = base * 2; 1191 else if (imp == TIPC_HIGH_IMPORTANCE) 1192 threshold = base * 100; 1193 else 1194 return 0; 1195 1196 if (msg_connected(msg)) 1197 threshold *= 4; 1198 1199 return queue_size >= threshold; 1200 } 1201 1202 /** 1203 * filter_rcv - validate incoming message 1204 * @sk: socket 1205 * @buf: message 1206 * 1207 * Enqueues message on receive queue if acceptable; optionally handles 1208 * disconnect indication for a connected socket. 1209 * 1210 * Called with socket lock already taken; port lock may also be taken. 1211 * 1212 * Returns TIPC error status code (TIPC_OK if message is not to be rejected) 1213 */ 1214 1215 static u32 filter_rcv(struct sock *sk, struct sk_buff *buf) 1216 { 1217 struct socket *sock = sk->sk_socket; 1218 struct tipc_msg *msg = buf_msg(buf); 1219 u32 recv_q_len; 1220 1221 /* Reject message if it is wrong sort of message for socket */ 1222 1223 /* 1224 * WOULD IT BE BETTER TO JUST DISCARD THESE MESSAGES INSTEAD? 1225 * "NO PORT" ISN'T REALLY THE RIGHT ERROR CODE, AND THERE MAY 1226 * BE SECURITY IMPLICATIONS INHERENT IN REJECTING INVALID TRAFFIC 1227 */ 1228 1229 if (sock->state == SS_READY) { 1230 if (msg_connected(msg)) 1231 return TIPC_ERR_NO_PORT; 1232 } else { 1233 if (msg_mcast(msg)) 1234 return TIPC_ERR_NO_PORT; 1235 if (sock->state == SS_CONNECTED) { 1236 if (!msg_connected(msg)) 1237 return TIPC_ERR_NO_PORT; 1238 } else if (sock->state == SS_CONNECTING) { 1239 if (!msg_connected(msg) && (msg_errcode(msg) == 0)) 1240 return TIPC_ERR_NO_PORT; 1241 } else if (sock->state == SS_LISTENING) { 1242 if (msg_connected(msg) || msg_errcode(msg)) 1243 return TIPC_ERR_NO_PORT; 1244 } else if (sock->state == SS_DISCONNECTING) { 1245 return TIPC_ERR_NO_PORT; 1246 } else /* (sock->state == SS_UNCONNECTED) */ { 1247 if (msg_connected(msg) || msg_errcode(msg)) 1248 return TIPC_ERR_NO_PORT; 1249 } 1250 } 1251 1252 /* Reject message if there isn't room to queue it */ 1253 1254 recv_q_len = (u32)atomic_read(&tipc_queue_size); 1255 if (unlikely(recv_q_len >= OVERLOAD_LIMIT_BASE)) { 1256 if (rx_queue_full(msg, recv_q_len, OVERLOAD_LIMIT_BASE)) 1257 return TIPC_ERR_OVERLOAD; 1258 } 1259 recv_q_len = skb_queue_len(&sk->sk_receive_queue); 1260 if (unlikely(recv_q_len >= (OVERLOAD_LIMIT_BASE / 2))) { 1261 if (rx_queue_full(msg, recv_q_len, OVERLOAD_LIMIT_BASE / 2)) 1262 return TIPC_ERR_OVERLOAD; 1263 } 1264 1265 /* Enqueue message (finally!) */ 1266 1267 TIPC_SKB_CB(buf)->handle = 0; 1268 atomic_inc(&tipc_queue_size); 1269 __skb_queue_tail(&sk->sk_receive_queue, buf); 1270 1271 /* Initiate connection termination for an incoming 'FIN' */ 1272 1273 if (unlikely(msg_errcode(msg) && (sock->state == SS_CONNECTED))) { 1274 sock->state = SS_DISCONNECTING; 1275 tipc_disconnect_port(tipc_sk_port(sk)); 1276 } 1277 1278 if (waitqueue_active(sk_sleep(sk))) 1279 wake_up_interruptible(sk_sleep(sk)); 1280 return TIPC_OK; 1281 } 1282 1283 /** 1284 * backlog_rcv - handle incoming message from backlog queue 1285 * @sk: socket 1286 * @buf: message 1287 * 1288 * Caller must hold socket lock, but not port lock. 1289 * 1290 * Returns 0 1291 */ 1292 1293 static int backlog_rcv(struct sock *sk, struct sk_buff *buf) 1294 { 1295 u32 res; 1296 1297 res = filter_rcv(sk, buf); 1298 if (res) 1299 tipc_reject_msg(buf, res); 1300 return 0; 1301 } 1302 1303 /** 1304 * dispatch - handle incoming message 1305 * @tport: TIPC port that received message 1306 * @buf: message 1307 * 1308 * Called with port lock already taken. 1309 * 1310 * Returns TIPC error status code (TIPC_OK if message is not to be rejected) 1311 */ 1312 1313 static u32 dispatch(struct tipc_port *tport, struct sk_buff *buf) 1314 { 1315 struct sock *sk = (struct sock *)tport->usr_handle; 1316 u32 res; 1317 1318 /* 1319 * Process message if socket is unlocked; otherwise add to backlog queue 1320 * 1321 * This code is based on sk_receive_skb(), but must be distinct from it 1322 * since a TIPC-specific filter/reject mechanism is utilized 1323 */ 1324 1325 bh_lock_sock(sk); 1326 if (!sock_owned_by_user(sk)) { 1327 res = filter_rcv(sk, buf); 1328 } else { 1329 if (sk_add_backlog(sk, buf)) 1330 res = TIPC_ERR_OVERLOAD; 1331 else 1332 res = TIPC_OK; 1333 } 1334 bh_unlock_sock(sk); 1335 1336 return res; 1337 } 1338 1339 /** 1340 * wakeupdispatch - wake up port after congestion 1341 * @tport: port to wakeup 1342 * 1343 * Called with port lock already taken. 1344 */ 1345 1346 static void wakeupdispatch(struct tipc_port *tport) 1347 { 1348 struct sock *sk = (struct sock *)tport->usr_handle; 1349 1350 if (waitqueue_active(sk_sleep(sk))) 1351 wake_up_interruptible(sk_sleep(sk)); 1352 } 1353 1354 /** 1355 * connect - establish a connection to another TIPC port 1356 * @sock: socket structure 1357 * @dest: socket address for destination port 1358 * @destlen: size of socket address data structure 1359 * @flags: file-related flags associated with socket 1360 * 1361 * Returns 0 on success, errno otherwise 1362 */ 1363 1364 static int connect(struct socket *sock, struct sockaddr *dest, int destlen, 1365 int flags) 1366 { 1367 struct sock *sk = sock->sk; 1368 struct sockaddr_tipc *dst = (struct sockaddr_tipc *)dest; 1369 struct msghdr m = {NULL,}; 1370 struct sk_buff *buf; 1371 struct tipc_msg *msg; 1372 long timeout; 1373 int res; 1374 1375 lock_sock(sk); 1376 1377 /* For now, TIPC does not allow use of connect() with DGRAM/RDM types */ 1378 1379 if (sock->state == SS_READY) { 1380 res = -EOPNOTSUPP; 1381 goto exit; 1382 } 1383 1384 /* For now, TIPC does not support the non-blocking form of connect() */ 1385 1386 if (flags & O_NONBLOCK) { 1387 res = -EOPNOTSUPP; 1388 goto exit; 1389 } 1390 1391 /* Issue Posix-compliant error code if socket is in the wrong state */ 1392 1393 if (sock->state == SS_LISTENING) { 1394 res = -EOPNOTSUPP; 1395 goto exit; 1396 } 1397 if (sock->state == SS_CONNECTING) { 1398 res = -EALREADY; 1399 goto exit; 1400 } 1401 if (sock->state != SS_UNCONNECTED) { 1402 res = -EISCONN; 1403 goto exit; 1404 } 1405 1406 /* 1407 * Reject connection attempt using multicast address 1408 * 1409 * Note: send_msg() validates the rest of the address fields, 1410 * so there's no need to do it here 1411 */ 1412 1413 if (dst->addrtype == TIPC_ADDR_MCAST) { 1414 res = -EINVAL; 1415 goto exit; 1416 } 1417 1418 /* Reject any messages already in receive queue (very unlikely) */ 1419 1420 reject_rx_queue(sk); 1421 1422 /* Send a 'SYN-' to destination */ 1423 1424 m.msg_name = dest; 1425 m.msg_namelen = destlen; 1426 res = send_msg(NULL, sock, &m, 0); 1427 if (res < 0) 1428 goto exit; 1429 1430 /* Wait until an 'ACK' or 'RST' arrives, or a timeout occurs */ 1431 1432 timeout = tipc_sk(sk)->conn_timeout; 1433 release_sock(sk); 1434 res = wait_event_interruptible_timeout(*sk_sleep(sk), 1435 (!skb_queue_empty(&sk->sk_receive_queue) || 1436 (sock->state != SS_CONNECTING)), 1437 timeout ? timeout : MAX_SCHEDULE_TIMEOUT); 1438 lock_sock(sk); 1439 1440 if (res > 0) { 1441 buf = skb_peek(&sk->sk_receive_queue); 1442 if (buf != NULL) { 1443 msg = buf_msg(buf); 1444 res = auto_connect(sock, msg); 1445 if (!res) { 1446 if (!msg_data_sz(msg)) 1447 advance_rx_queue(sk); 1448 } 1449 } else { 1450 if (sock->state == SS_CONNECTED) 1451 res = -EISCONN; 1452 else 1453 res = -ECONNREFUSED; 1454 } 1455 } else { 1456 if (res == 0) 1457 res = -ETIMEDOUT; 1458 else 1459 ; /* leave "res" unchanged */ 1460 sock->state = SS_DISCONNECTING; 1461 } 1462 1463 exit: 1464 release_sock(sk); 1465 return res; 1466 } 1467 1468 /** 1469 * listen - allow socket to listen for incoming connections 1470 * @sock: socket structure 1471 * @len: (unused) 1472 * 1473 * Returns 0 on success, errno otherwise 1474 */ 1475 1476 static int listen(struct socket *sock, int len) 1477 { 1478 struct sock *sk = sock->sk; 1479 int res; 1480 1481 lock_sock(sk); 1482 1483 if (sock->state == SS_READY) 1484 res = -EOPNOTSUPP; 1485 else if (sock->state != SS_UNCONNECTED) 1486 res = -EINVAL; 1487 else { 1488 sock->state = SS_LISTENING; 1489 res = 0; 1490 } 1491 1492 release_sock(sk); 1493 return res; 1494 } 1495 1496 /** 1497 * accept - wait for connection request 1498 * @sock: listening socket 1499 * @newsock: new socket that is to be connected 1500 * @flags: file-related flags associated with socket 1501 * 1502 * Returns 0 on success, errno otherwise 1503 */ 1504 1505 static int accept(struct socket *sock, struct socket *new_sock, int flags) 1506 { 1507 struct sock *sk = sock->sk; 1508 struct sk_buff *buf; 1509 int res; 1510 1511 lock_sock(sk); 1512 1513 if (sock->state == SS_READY) { 1514 res = -EOPNOTSUPP; 1515 goto exit; 1516 } 1517 if (sock->state != SS_LISTENING) { 1518 res = -EINVAL; 1519 goto exit; 1520 } 1521 1522 while (skb_queue_empty(&sk->sk_receive_queue)) { 1523 if (flags & O_NONBLOCK) { 1524 res = -EWOULDBLOCK; 1525 goto exit; 1526 } 1527 release_sock(sk); 1528 res = wait_event_interruptible(*sk_sleep(sk), 1529 (!skb_queue_empty(&sk->sk_receive_queue))); 1530 lock_sock(sk); 1531 if (res) 1532 goto exit; 1533 } 1534 1535 buf = skb_peek(&sk->sk_receive_queue); 1536 1537 res = tipc_create(sock_net(sock->sk), new_sock, 0, 0); 1538 if (!res) { 1539 struct sock *new_sk = new_sock->sk; 1540 struct tipc_sock *new_tsock = tipc_sk(new_sk); 1541 struct tipc_port *new_tport = new_tsock->p; 1542 u32 new_ref = new_tport->ref; 1543 struct tipc_msg *msg = buf_msg(buf); 1544 1545 lock_sock(new_sk); 1546 1547 /* 1548 * Reject any stray messages received by new socket 1549 * before the socket lock was taken (very, very unlikely) 1550 */ 1551 1552 reject_rx_queue(new_sk); 1553 1554 /* Connect new socket to it's peer */ 1555 1556 new_tsock->peer_name.ref = msg_origport(msg); 1557 new_tsock->peer_name.node = msg_orignode(msg); 1558 tipc_connect2port(new_ref, &new_tsock->peer_name); 1559 new_sock->state = SS_CONNECTED; 1560 1561 tipc_set_portimportance(new_ref, msg_importance(msg)); 1562 if (msg_named(msg)) { 1563 new_tport->conn_type = msg_nametype(msg); 1564 new_tport->conn_instance = msg_nameinst(msg); 1565 } 1566 1567 /* 1568 * Respond to 'SYN-' by discarding it & returning 'ACK'-. 1569 * Respond to 'SYN+' by queuing it on new socket. 1570 */ 1571 1572 if (!msg_data_sz(msg)) { 1573 struct msghdr m = {NULL,}; 1574 1575 advance_rx_queue(sk); 1576 send_packet(NULL, new_sock, &m, 0); 1577 } else { 1578 __skb_dequeue(&sk->sk_receive_queue); 1579 __skb_queue_head(&new_sk->sk_receive_queue, buf); 1580 } 1581 release_sock(new_sk); 1582 } 1583 exit: 1584 release_sock(sk); 1585 return res; 1586 } 1587 1588 /** 1589 * shutdown - shutdown socket connection 1590 * @sock: socket structure 1591 * @how: direction to close (must be SHUT_RDWR) 1592 * 1593 * Terminates connection (if necessary), then purges socket's receive queue. 1594 * 1595 * Returns 0 on success, errno otherwise 1596 */ 1597 1598 static int shutdown(struct socket *sock, int how) 1599 { 1600 struct sock *sk = sock->sk; 1601 struct tipc_port *tport = tipc_sk_port(sk); 1602 struct sk_buff *buf; 1603 int res; 1604 1605 if (how != SHUT_RDWR) 1606 return -EINVAL; 1607 1608 lock_sock(sk); 1609 1610 switch (sock->state) { 1611 case SS_CONNECTING: 1612 case SS_CONNECTED: 1613 1614 /* Disconnect and send a 'FIN+' or 'FIN-' message to peer */ 1615 restart: 1616 buf = __skb_dequeue(&sk->sk_receive_queue); 1617 if (buf) { 1618 atomic_dec(&tipc_queue_size); 1619 if (TIPC_SKB_CB(buf)->handle != 0) { 1620 buf_discard(buf); 1621 goto restart; 1622 } 1623 tipc_disconnect(tport->ref); 1624 tipc_reject_msg(buf, TIPC_CONN_SHUTDOWN); 1625 } else { 1626 tipc_shutdown(tport->ref); 1627 } 1628 1629 sock->state = SS_DISCONNECTING; 1630 1631 /* fall through */ 1632 1633 case SS_DISCONNECTING: 1634 1635 /* Discard any unreceived messages; wake up sleeping tasks */ 1636 1637 discard_rx_queue(sk); 1638 if (waitqueue_active(sk_sleep(sk))) 1639 wake_up_interruptible(sk_sleep(sk)); 1640 res = 0; 1641 break; 1642 1643 default: 1644 res = -ENOTCONN; 1645 } 1646 1647 release_sock(sk); 1648 return res; 1649 } 1650 1651 /** 1652 * setsockopt - set socket option 1653 * @sock: socket structure 1654 * @lvl: option level 1655 * @opt: option identifier 1656 * @ov: pointer to new option value 1657 * @ol: length of option value 1658 * 1659 * For stream sockets only, accepts and ignores all IPPROTO_TCP options 1660 * (to ease compatibility). 1661 * 1662 * Returns 0 on success, errno otherwise 1663 */ 1664 1665 static int setsockopt(struct socket *sock, 1666 int lvl, int opt, char __user *ov, unsigned int ol) 1667 { 1668 struct sock *sk = sock->sk; 1669 struct tipc_port *tport = tipc_sk_port(sk); 1670 u32 value; 1671 int res; 1672 1673 if ((lvl == IPPROTO_TCP) && (sock->type == SOCK_STREAM)) 1674 return 0; 1675 if (lvl != SOL_TIPC) 1676 return -ENOPROTOOPT; 1677 if (ol < sizeof(value)) 1678 return -EINVAL; 1679 res = get_user(value, (u32 __user *)ov); 1680 if (res) 1681 return res; 1682 1683 lock_sock(sk); 1684 1685 switch (opt) { 1686 case TIPC_IMPORTANCE: 1687 res = tipc_set_portimportance(tport->ref, value); 1688 break; 1689 case TIPC_SRC_DROPPABLE: 1690 if (sock->type != SOCK_STREAM) 1691 res = tipc_set_portunreliable(tport->ref, value); 1692 else 1693 res = -ENOPROTOOPT; 1694 break; 1695 case TIPC_DEST_DROPPABLE: 1696 res = tipc_set_portunreturnable(tport->ref, value); 1697 break; 1698 case TIPC_CONN_TIMEOUT: 1699 tipc_sk(sk)->conn_timeout = msecs_to_jiffies(value); 1700 /* no need to set "res", since already 0 at this point */ 1701 break; 1702 default: 1703 res = -EINVAL; 1704 } 1705 1706 release_sock(sk); 1707 1708 return res; 1709 } 1710 1711 /** 1712 * getsockopt - get socket option 1713 * @sock: socket structure 1714 * @lvl: option level 1715 * @opt: option identifier 1716 * @ov: receptacle for option value 1717 * @ol: receptacle for length of option value 1718 * 1719 * For stream sockets only, returns 0 length result for all IPPROTO_TCP options 1720 * (to ease compatibility). 1721 * 1722 * Returns 0 on success, errno otherwise 1723 */ 1724 1725 static int getsockopt(struct socket *sock, 1726 int lvl, int opt, char __user *ov, int __user *ol) 1727 { 1728 struct sock *sk = sock->sk; 1729 struct tipc_port *tport = tipc_sk_port(sk); 1730 int len; 1731 u32 value; 1732 int res; 1733 1734 if ((lvl == IPPROTO_TCP) && (sock->type == SOCK_STREAM)) 1735 return put_user(0, ol); 1736 if (lvl != SOL_TIPC) 1737 return -ENOPROTOOPT; 1738 res = get_user(len, ol); 1739 if (res) 1740 return res; 1741 1742 lock_sock(sk); 1743 1744 switch (opt) { 1745 case TIPC_IMPORTANCE: 1746 res = tipc_portimportance(tport->ref, &value); 1747 break; 1748 case TIPC_SRC_DROPPABLE: 1749 res = tipc_portunreliable(tport->ref, &value); 1750 break; 1751 case TIPC_DEST_DROPPABLE: 1752 res = tipc_portunreturnable(tport->ref, &value); 1753 break; 1754 case TIPC_CONN_TIMEOUT: 1755 value = jiffies_to_msecs(tipc_sk(sk)->conn_timeout); 1756 /* no need to set "res", since already 0 at this point */ 1757 break; 1758 case TIPC_NODE_RECVQ_DEPTH: 1759 value = (u32)atomic_read(&tipc_queue_size); 1760 break; 1761 case TIPC_SOCK_RECVQ_DEPTH: 1762 value = skb_queue_len(&sk->sk_receive_queue); 1763 break; 1764 default: 1765 res = -EINVAL; 1766 } 1767 1768 release_sock(sk); 1769 1770 if (res) 1771 return res; /* "get" failed */ 1772 1773 if (len < sizeof(value)) 1774 return -EINVAL; 1775 1776 if (copy_to_user(ov, &value, sizeof(value))) 1777 return -EFAULT; 1778 1779 return put_user(sizeof(value), ol); 1780 } 1781 1782 /** 1783 * Protocol switches for the various types of TIPC sockets 1784 */ 1785 1786 static const struct proto_ops msg_ops = { 1787 .owner = THIS_MODULE, 1788 .family = AF_TIPC, 1789 .release = release, 1790 .bind = bind, 1791 .connect = connect, 1792 .socketpair = sock_no_socketpair, 1793 .accept = accept, 1794 .getname = get_name, 1795 .poll = poll, 1796 .ioctl = sock_no_ioctl, 1797 .listen = listen, 1798 .shutdown = shutdown, 1799 .setsockopt = setsockopt, 1800 .getsockopt = getsockopt, 1801 .sendmsg = send_msg, 1802 .recvmsg = recv_msg, 1803 .mmap = sock_no_mmap, 1804 .sendpage = sock_no_sendpage 1805 }; 1806 1807 static const struct proto_ops packet_ops = { 1808 .owner = THIS_MODULE, 1809 .family = AF_TIPC, 1810 .release = release, 1811 .bind = bind, 1812 .connect = connect, 1813 .socketpair = sock_no_socketpair, 1814 .accept = accept, 1815 .getname = get_name, 1816 .poll = poll, 1817 .ioctl = sock_no_ioctl, 1818 .listen = listen, 1819 .shutdown = shutdown, 1820 .setsockopt = setsockopt, 1821 .getsockopt = getsockopt, 1822 .sendmsg = send_packet, 1823 .recvmsg = recv_msg, 1824 .mmap = sock_no_mmap, 1825 .sendpage = sock_no_sendpage 1826 }; 1827 1828 static const struct proto_ops stream_ops = { 1829 .owner = THIS_MODULE, 1830 .family = AF_TIPC, 1831 .release = release, 1832 .bind = bind, 1833 .connect = connect, 1834 .socketpair = sock_no_socketpair, 1835 .accept = accept, 1836 .getname = get_name, 1837 .poll = poll, 1838 .ioctl = sock_no_ioctl, 1839 .listen = listen, 1840 .shutdown = shutdown, 1841 .setsockopt = setsockopt, 1842 .getsockopt = getsockopt, 1843 .sendmsg = send_stream, 1844 .recvmsg = recv_stream, 1845 .mmap = sock_no_mmap, 1846 .sendpage = sock_no_sendpage 1847 }; 1848 1849 static const struct net_proto_family tipc_family_ops = { 1850 .owner = THIS_MODULE, 1851 .family = AF_TIPC, 1852 .create = tipc_create 1853 }; 1854 1855 static struct proto tipc_proto = { 1856 .name = "TIPC", 1857 .owner = THIS_MODULE, 1858 .obj_size = sizeof(struct tipc_sock) 1859 }; 1860 1861 /** 1862 * tipc_socket_init - initialize TIPC socket interface 1863 * 1864 * Returns 0 on success, errno otherwise 1865 */ 1866 int tipc_socket_init(void) 1867 { 1868 int res; 1869 1870 res = proto_register(&tipc_proto, 1); 1871 if (res) { 1872 err("Failed to register TIPC protocol type\n"); 1873 goto out; 1874 } 1875 1876 res = sock_register(&tipc_family_ops); 1877 if (res) { 1878 err("Failed to register TIPC socket type\n"); 1879 proto_unregister(&tipc_proto); 1880 goto out; 1881 } 1882 1883 sockets_enabled = 1; 1884 out: 1885 return res; 1886 } 1887 1888 /** 1889 * tipc_socket_stop - stop TIPC socket interface 1890 */ 1891 1892 void tipc_socket_stop(void) 1893 { 1894 if (!sockets_enabled) 1895 return; 1896 1897 sockets_enabled = 0; 1898 sock_unregister(tipc_family_ops.family); 1899 proto_unregister(&tipc_proto); 1900 } 1901 1902