1 /* 2 * net/tipc/socket.c: TIPC socket API 3 * 4 * Copyright (c) 2001-2007, 2012 Ericsson AB 5 * Copyright (c) 2004-2008, 2010-2012, 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 "core.h" 38 #include "port.h" 39 40 #include <linux/export.h> 41 #include <net/sock.h> 42 43 #define SS_LISTENING -1 /* socket is listening */ 44 #define SS_READY -2 /* socket is connectionless */ 45 46 #define OVERLOAD_LIMIT_BASE 10000 47 #define CONN_TIMEOUT_DEFAULT 8000 /* default connect timeout = 8s */ 48 49 struct tipc_sock { 50 struct sock sk; 51 struct tipc_port *p; 52 struct tipc_portid peer_name; 53 unsigned int conn_timeout; 54 }; 55 56 #define tipc_sk(sk) ((struct tipc_sock *)(sk)) 57 #define tipc_sk_port(sk) (tipc_sk(sk)->p) 58 59 #define tipc_rx_ready(sock) (!skb_queue_empty(&sock->sk->sk_receive_queue) || \ 60 (sock->state == SS_DISCONNECTING)) 61 62 static int backlog_rcv(struct sock *sk, struct sk_buff *skb); 63 static u32 dispatch(struct tipc_port *tport, struct sk_buff *buf); 64 static void wakeupdispatch(struct tipc_port *tport); 65 static void tipc_data_ready(struct sock *sk, int len); 66 static void tipc_write_space(struct sock *sk); 67 68 static const struct proto_ops packet_ops; 69 static const struct proto_ops stream_ops; 70 static const struct proto_ops msg_ops; 71 72 static struct proto tipc_proto; 73 74 static int sockets_enabled; 75 76 /* 77 * Revised TIPC socket locking policy: 78 * 79 * Most socket operations take the standard socket lock when they start 80 * and hold it until they finish (or until they need to sleep). Acquiring 81 * this lock grants the owner exclusive access to the fields of the socket 82 * data structures, with the exception of the backlog queue. A few socket 83 * operations can be done without taking the socket lock because they only 84 * read socket information that never changes during the life of the socket. 85 * 86 * Socket operations may acquire the lock for the associated TIPC port if they 87 * need to perform an operation on the port. If any routine needs to acquire 88 * both the socket lock and the port lock it must take the socket lock first 89 * to avoid the risk of deadlock. 90 * 91 * The dispatcher handling incoming messages cannot grab the socket lock in 92 * the standard fashion, since invoked it runs at the BH level and cannot block. 93 * Instead, it checks to see if the socket lock is currently owned by someone, 94 * and either handles the message itself or adds it to the socket's backlog 95 * queue; in the latter case the queued message is processed once the process 96 * owning the socket lock releases it. 97 * 98 * NOTE: Releasing the socket lock while an operation is sleeping overcomes 99 * the problem of a blocked socket operation preventing any other operations 100 * from occurring. However, applications must be careful if they have 101 * multiple threads trying to send (or receive) on the same socket, as these 102 * operations might interfere with each other. For example, doing a connect 103 * and a receive at the same time might allow the receive to consume the 104 * ACK message meant for the connect. While additional work could be done 105 * to try and overcome this, it doesn't seem to be worthwhile at the present. 106 * 107 * NOTE: Releasing the socket lock while an operation is sleeping also ensures 108 * that another operation that must be performed in a non-blocking manner is 109 * not delayed for very long because the lock has already been taken. 110 * 111 * NOTE: This code assumes that certain fields of a port/socket pair are 112 * constant over its lifetime; such fields can be examined without taking 113 * the socket lock and/or port lock, and do not need to be re-read even 114 * after resuming processing after waiting. These fields include: 115 * - socket type 116 * - pointer to socket sk structure (aka tipc_sock structure) 117 * - pointer to port structure 118 * - port reference 119 */ 120 121 /** 122 * advance_rx_queue - discard first buffer in socket receive queue 123 * 124 * Caller must hold socket lock 125 */ 126 static void advance_rx_queue(struct sock *sk) 127 { 128 kfree_skb(__skb_dequeue(&sk->sk_receive_queue)); 129 } 130 131 /** 132 * discard_rx_queue - discard all buffers in socket receive queue 133 * 134 * Caller must hold socket lock 135 */ 136 static void discard_rx_queue(struct sock *sk) 137 { 138 struct sk_buff *buf; 139 140 while ((buf = __skb_dequeue(&sk->sk_receive_queue))) 141 kfree_skb(buf); 142 } 143 144 /** 145 * reject_rx_queue - reject all buffers in socket receive queue 146 * 147 * Caller must hold socket lock 148 */ 149 static void reject_rx_queue(struct sock *sk) 150 { 151 struct sk_buff *buf; 152 153 while ((buf = __skb_dequeue(&sk->sk_receive_queue))) 154 tipc_reject_msg(buf, TIPC_ERR_NO_PORT); 155 } 156 157 /** 158 * tipc_create - create a TIPC socket 159 * @net: network namespace (must be default network) 160 * @sock: pre-allocated socket structure 161 * @protocol: protocol indicator (must be 0) 162 * @kern: caused by kernel or by userspace? 163 * 164 * This routine creates additional data structures used by the TIPC socket, 165 * initializes them, and links them together. 166 * 167 * Returns 0 on success, errno otherwise 168 */ 169 static int tipc_create(struct net *net, struct socket *sock, int protocol, 170 int kern) 171 { 172 const struct proto_ops *ops; 173 socket_state state; 174 struct sock *sk; 175 struct tipc_port *tp_ptr; 176 177 /* Validate arguments */ 178 if (unlikely(protocol != 0)) 179 return -EPROTONOSUPPORT; 180 181 switch (sock->type) { 182 case SOCK_STREAM: 183 ops = &stream_ops; 184 state = SS_UNCONNECTED; 185 break; 186 case SOCK_SEQPACKET: 187 ops = &packet_ops; 188 state = SS_UNCONNECTED; 189 break; 190 case SOCK_DGRAM: 191 case SOCK_RDM: 192 ops = &msg_ops; 193 state = SS_READY; 194 break; 195 default: 196 return -EPROTOTYPE; 197 } 198 199 /* Allocate socket's protocol area */ 200 sk = sk_alloc(net, AF_TIPC, GFP_KERNEL, &tipc_proto); 201 if (sk == NULL) 202 return -ENOMEM; 203 204 /* Allocate TIPC port for socket to use */ 205 tp_ptr = tipc_createport_raw(sk, &dispatch, &wakeupdispatch, 206 TIPC_LOW_IMPORTANCE); 207 if (unlikely(!tp_ptr)) { 208 sk_free(sk); 209 return -ENOMEM; 210 } 211 212 /* Finish initializing socket data structures */ 213 sock->ops = ops; 214 sock->state = state; 215 216 sock_init_data(sock, sk); 217 sk->sk_backlog_rcv = backlog_rcv; 218 sk->sk_rcvbuf = TIPC_FLOW_CONTROL_WIN * 2 * TIPC_MAX_USER_MSG_SIZE * 2; 219 sk->sk_data_ready = tipc_data_ready; 220 sk->sk_write_space = tipc_write_space; 221 tipc_sk(sk)->p = tp_ptr; 222 tipc_sk(sk)->conn_timeout = CONN_TIMEOUT_DEFAULT; 223 224 spin_unlock_bh(tp_ptr->lock); 225 226 if (sock->state == SS_READY) { 227 tipc_set_portunreturnable(tp_ptr->ref, 1); 228 if (sock->type == SOCK_DGRAM) 229 tipc_set_portunreliable(tp_ptr->ref, 1); 230 } 231 232 return 0; 233 } 234 235 /** 236 * release - destroy a TIPC socket 237 * @sock: socket to destroy 238 * 239 * This routine cleans up any messages that are still queued on the socket. 240 * For DGRAM and RDM socket types, all queued messages are rejected. 241 * For SEQPACKET and STREAM socket types, the first message is rejected 242 * and any others are discarded. (If the first message on a STREAM socket 243 * is partially-read, it is discarded and the next one is rejected instead.) 244 * 245 * NOTE: Rejected messages are not necessarily returned to the sender! They 246 * are returned or discarded according to the "destination droppable" setting 247 * specified for the message by the sender. 248 * 249 * Returns 0 on success, errno otherwise 250 */ 251 static int release(struct socket *sock) 252 { 253 struct sock *sk = sock->sk; 254 struct tipc_port *tport; 255 struct sk_buff *buf; 256 int res; 257 258 /* 259 * Exit if socket isn't fully initialized (occurs when a failed accept() 260 * releases a pre-allocated child socket that was never used) 261 */ 262 if (sk == NULL) 263 return 0; 264 265 tport = tipc_sk_port(sk); 266 lock_sock(sk); 267 268 /* 269 * Reject all unreceived messages, except on an active connection 270 * (which disconnects locally & sends a 'FIN+' to peer) 271 */ 272 while (sock->state != SS_DISCONNECTING) { 273 buf = __skb_dequeue(&sk->sk_receive_queue); 274 if (buf == NULL) 275 break; 276 if (TIPC_SKB_CB(buf)->handle != 0) 277 kfree_skb(buf); 278 else { 279 if ((sock->state == SS_CONNECTING) || 280 (sock->state == SS_CONNECTED)) { 281 sock->state = SS_DISCONNECTING; 282 tipc_disconnect(tport->ref); 283 } 284 tipc_reject_msg(buf, TIPC_ERR_NO_PORT); 285 } 286 } 287 288 /* 289 * Delete TIPC port; this ensures no more messages are queued 290 * (also disconnects an active connection & sends a 'FIN-' to peer) 291 */ 292 res = tipc_deleteport(tport->ref); 293 294 /* Discard any remaining (connection-based) messages in receive queue */ 295 discard_rx_queue(sk); 296 297 /* Reject any messages that accumulated in backlog queue */ 298 sock->state = SS_DISCONNECTING; 299 release_sock(sk); 300 301 sock_put(sk); 302 sock->sk = NULL; 303 304 return res; 305 } 306 307 /** 308 * bind - associate or disassocate TIPC name(s) with a socket 309 * @sock: socket structure 310 * @uaddr: socket address describing name(s) and desired operation 311 * @uaddr_len: size of socket address data structure 312 * 313 * Name and name sequence binding is indicated using a positive scope value; 314 * a negative scope value unbinds the specified name. Specifying no name 315 * (i.e. a socket address length of 0) unbinds all names from the socket. 316 * 317 * Returns 0 on success, errno otherwise 318 * 319 * NOTE: This routine doesn't need to take the socket lock since it doesn't 320 * access any non-constant socket information. 321 */ 322 static int bind(struct socket *sock, struct sockaddr *uaddr, int uaddr_len) 323 { 324 struct sockaddr_tipc *addr = (struct sockaddr_tipc *)uaddr; 325 u32 portref = tipc_sk_port(sock->sk)->ref; 326 327 if (unlikely(!uaddr_len)) 328 return tipc_withdraw(portref, 0, NULL); 329 330 if (uaddr_len < sizeof(struct sockaddr_tipc)) 331 return -EINVAL; 332 if (addr->family != AF_TIPC) 333 return -EAFNOSUPPORT; 334 335 if (addr->addrtype == TIPC_ADDR_NAME) 336 addr->addr.nameseq.upper = addr->addr.nameseq.lower; 337 else if (addr->addrtype != TIPC_ADDR_NAMESEQ) 338 return -EAFNOSUPPORT; 339 340 if (addr->addr.nameseq.type < TIPC_RESERVED_TYPES) 341 return -EACCES; 342 343 return (addr->scope > 0) ? 344 tipc_publish(portref, addr->scope, &addr->addr.nameseq) : 345 tipc_withdraw(portref, -addr->scope, &addr->addr.nameseq); 346 } 347 348 /** 349 * get_name - get port ID of socket or peer socket 350 * @sock: socket structure 351 * @uaddr: area for returned socket address 352 * @uaddr_len: area for returned length of socket address 353 * @peer: 0 = own ID, 1 = current peer ID, 2 = current/former peer ID 354 * 355 * Returns 0 on success, errno otherwise 356 * 357 * NOTE: This routine doesn't need to take the socket lock since it only 358 * accesses socket information that is unchanging (or which changes in 359 * a completely predictable manner). 360 */ 361 static int get_name(struct socket *sock, struct sockaddr *uaddr, 362 int *uaddr_len, int peer) 363 { 364 struct sockaddr_tipc *addr = (struct sockaddr_tipc *)uaddr; 365 struct tipc_sock *tsock = tipc_sk(sock->sk); 366 367 memset(addr, 0, sizeof(*addr)); 368 if (peer) { 369 if ((sock->state != SS_CONNECTED) && 370 ((peer != 2) || (sock->state != SS_DISCONNECTING))) 371 return -ENOTCONN; 372 addr->addr.id.ref = tsock->peer_name.ref; 373 addr->addr.id.node = tsock->peer_name.node; 374 } else { 375 addr->addr.id.ref = tsock->p->ref; 376 addr->addr.id.node = tipc_own_addr; 377 } 378 379 *uaddr_len = sizeof(*addr); 380 addr->addrtype = TIPC_ADDR_ID; 381 addr->family = AF_TIPC; 382 addr->scope = 0; 383 addr->addr.name.domain = 0; 384 385 return 0; 386 } 387 388 /** 389 * poll - read and possibly block on pollmask 390 * @file: file structure associated with the socket 391 * @sock: socket for which to calculate the poll bits 392 * @wait: ??? 393 * 394 * Returns pollmask value 395 * 396 * COMMENTARY: 397 * It appears that the usual socket locking mechanisms are not useful here 398 * since the pollmask info is potentially out-of-date the moment this routine 399 * exits. TCP and other protocols seem to rely on higher level poll routines 400 * to handle any preventable race conditions, so TIPC will do the same ... 401 * 402 * TIPC sets the returned events as follows: 403 * 404 * socket state flags set 405 * ------------ --------- 406 * unconnected no read flags 407 * POLLOUT if port is not congested 408 * 409 * connecting POLLIN/POLLRDNORM if ACK/NACK in rx queue 410 * no write flags 411 * 412 * connected POLLIN/POLLRDNORM if data in rx queue 413 * POLLOUT if port is not congested 414 * 415 * disconnecting POLLIN/POLLRDNORM/POLLHUP 416 * no write flags 417 * 418 * listening POLLIN if SYN in rx queue 419 * no write flags 420 * 421 * ready POLLIN/POLLRDNORM if data in rx queue 422 * [connectionless] POLLOUT (since port cannot be congested) 423 * 424 * IMPORTANT: The fact that a read or write operation is indicated does NOT 425 * imply that the operation will succeed, merely that it should be performed 426 * and will not block. 427 */ 428 static unsigned int poll(struct file *file, struct socket *sock, 429 poll_table *wait) 430 { 431 struct sock *sk = sock->sk; 432 u32 mask = 0; 433 434 sock_poll_wait(file, sk_sleep(sk), wait); 435 436 switch ((int)sock->state) { 437 case SS_UNCONNECTED: 438 if (!tipc_sk_port(sk)->congested) 439 mask |= POLLOUT; 440 break; 441 case SS_READY: 442 case SS_CONNECTED: 443 if (!tipc_sk_port(sk)->congested) 444 mask |= POLLOUT; 445 /* fall thru' */ 446 case SS_CONNECTING: 447 case SS_LISTENING: 448 if (!skb_queue_empty(&sk->sk_receive_queue)) 449 mask |= (POLLIN | POLLRDNORM); 450 break; 451 case SS_DISCONNECTING: 452 mask = (POLLIN | POLLRDNORM | POLLHUP); 453 break; 454 } 455 456 return mask; 457 } 458 459 /** 460 * dest_name_check - verify user is permitted to send to specified port name 461 * @dest: destination address 462 * @m: descriptor for message to be sent 463 * 464 * Prevents restricted configuration commands from being issued by 465 * unauthorized users. 466 * 467 * Returns 0 if permission is granted, otherwise errno 468 */ 469 static int dest_name_check(struct sockaddr_tipc *dest, struct msghdr *m) 470 { 471 struct tipc_cfg_msg_hdr hdr; 472 473 if (likely(dest->addr.name.name.type >= TIPC_RESERVED_TYPES)) 474 return 0; 475 if (likely(dest->addr.name.name.type == TIPC_TOP_SRV)) 476 return 0; 477 if (likely(dest->addr.name.name.type != TIPC_CFG_SRV)) 478 return -EACCES; 479 480 if (!m->msg_iovlen || (m->msg_iov[0].iov_len < sizeof(hdr))) 481 return -EMSGSIZE; 482 if (copy_from_user(&hdr, m->msg_iov[0].iov_base, sizeof(hdr))) 483 return -EFAULT; 484 if ((ntohs(hdr.tcm_type) & 0xC000) && (!capable(CAP_NET_ADMIN))) 485 return -EACCES; 486 487 return 0; 488 } 489 490 /** 491 * send_msg - send message in connectionless manner 492 * @iocb: if NULL, indicates that socket lock is already held 493 * @sock: socket structure 494 * @m: message to send 495 * @total_len: length of message 496 * 497 * Message must have an destination specified explicitly. 498 * Used for SOCK_RDM and SOCK_DGRAM messages, 499 * and for 'SYN' messages on SOCK_SEQPACKET and SOCK_STREAM connections. 500 * (Note: 'SYN+' is prohibited on SOCK_STREAM.) 501 * 502 * Returns the number of bytes sent on success, or errno otherwise 503 */ 504 static int send_msg(struct kiocb *iocb, struct socket *sock, 505 struct msghdr *m, size_t total_len) 506 { 507 struct sock *sk = sock->sk; 508 struct tipc_port *tport = tipc_sk_port(sk); 509 struct sockaddr_tipc *dest = (struct sockaddr_tipc *)m->msg_name; 510 int needs_conn; 511 long timeout_val; 512 int res = -EINVAL; 513 514 if (unlikely(!dest)) 515 return -EDESTADDRREQ; 516 if (unlikely((m->msg_namelen < sizeof(*dest)) || 517 (dest->family != AF_TIPC))) 518 return -EINVAL; 519 if ((total_len > TIPC_MAX_USER_MSG_SIZE) || 520 (m->msg_iovlen > (unsigned int)INT_MAX)) 521 return -EMSGSIZE; 522 523 if (iocb) 524 lock_sock(sk); 525 526 needs_conn = (sock->state != SS_READY); 527 if (unlikely(needs_conn)) { 528 if (sock->state == SS_LISTENING) { 529 res = -EPIPE; 530 goto exit; 531 } 532 if (sock->state != SS_UNCONNECTED) { 533 res = -EISCONN; 534 goto exit; 535 } 536 if ((tport->published) || 537 ((sock->type == SOCK_STREAM) && (total_len != 0))) { 538 res = -EOPNOTSUPP; 539 goto exit; 540 } 541 if (dest->addrtype == TIPC_ADDR_NAME) { 542 tport->conn_type = dest->addr.name.name.type; 543 tport->conn_instance = dest->addr.name.name.instance; 544 } 545 546 /* Abort any pending connection attempts (very unlikely) */ 547 reject_rx_queue(sk); 548 } 549 550 timeout_val = sock_sndtimeo(sk, m->msg_flags & MSG_DONTWAIT); 551 552 do { 553 if (dest->addrtype == TIPC_ADDR_NAME) { 554 res = dest_name_check(dest, m); 555 if (res) 556 break; 557 res = tipc_send2name(tport->ref, 558 &dest->addr.name.name, 559 dest->addr.name.domain, 560 m->msg_iovlen, 561 m->msg_iov, 562 total_len); 563 } else if (dest->addrtype == TIPC_ADDR_ID) { 564 res = tipc_send2port(tport->ref, 565 &dest->addr.id, 566 m->msg_iovlen, 567 m->msg_iov, 568 total_len); 569 } else if (dest->addrtype == TIPC_ADDR_MCAST) { 570 if (needs_conn) { 571 res = -EOPNOTSUPP; 572 break; 573 } 574 res = dest_name_check(dest, m); 575 if (res) 576 break; 577 res = tipc_multicast(tport->ref, 578 &dest->addr.nameseq, 579 m->msg_iovlen, 580 m->msg_iov, 581 total_len); 582 } 583 if (likely(res != -ELINKCONG)) { 584 if (needs_conn && (res >= 0)) 585 sock->state = SS_CONNECTING; 586 break; 587 } 588 if (timeout_val <= 0L) { 589 res = timeout_val ? timeout_val : -EWOULDBLOCK; 590 break; 591 } 592 release_sock(sk); 593 timeout_val = wait_event_interruptible_timeout(*sk_sleep(sk), 594 !tport->congested, timeout_val); 595 lock_sock(sk); 596 } while (1); 597 598 exit: 599 if (iocb) 600 release_sock(sk); 601 return res; 602 } 603 604 /** 605 * send_packet - send a connection-oriented message 606 * @iocb: if NULL, indicates that socket lock is already held 607 * @sock: socket structure 608 * @m: message to send 609 * @total_len: length of message 610 * 611 * Used for SOCK_SEQPACKET messages and SOCK_STREAM data. 612 * 613 * Returns the number of bytes sent on success, or errno otherwise 614 */ 615 static int send_packet(struct kiocb *iocb, struct socket *sock, 616 struct msghdr *m, size_t total_len) 617 { 618 struct sock *sk = sock->sk; 619 struct tipc_port *tport = tipc_sk_port(sk); 620 struct sockaddr_tipc *dest = (struct sockaddr_tipc *)m->msg_name; 621 long timeout_val; 622 int res; 623 624 /* Handle implied connection establishment */ 625 if (unlikely(dest)) 626 return send_msg(iocb, sock, m, total_len); 627 628 if ((total_len > TIPC_MAX_USER_MSG_SIZE) || 629 (m->msg_iovlen > (unsigned int)INT_MAX)) 630 return -EMSGSIZE; 631 632 if (iocb) 633 lock_sock(sk); 634 635 timeout_val = sock_sndtimeo(sk, m->msg_flags & MSG_DONTWAIT); 636 637 do { 638 if (unlikely(sock->state != SS_CONNECTED)) { 639 if (sock->state == SS_DISCONNECTING) 640 res = -EPIPE; 641 else 642 res = -ENOTCONN; 643 break; 644 } 645 646 res = tipc_send(tport->ref, m->msg_iovlen, m->msg_iov, 647 total_len); 648 if (likely(res != -ELINKCONG)) 649 break; 650 if (timeout_val <= 0L) { 651 res = timeout_val ? timeout_val : -EWOULDBLOCK; 652 break; 653 } 654 release_sock(sk); 655 timeout_val = wait_event_interruptible_timeout(*sk_sleep(sk), 656 (!tport->congested || !tport->connected), timeout_val); 657 lock_sock(sk); 658 } while (1); 659 660 if (iocb) 661 release_sock(sk); 662 return res; 663 } 664 665 /** 666 * send_stream - send stream-oriented data 667 * @iocb: (unused) 668 * @sock: socket structure 669 * @m: data to send 670 * @total_len: total length of data to be sent 671 * 672 * Used for SOCK_STREAM data. 673 * 674 * Returns the number of bytes sent on success (or partial success), 675 * or errno if no data sent 676 */ 677 static int send_stream(struct kiocb *iocb, struct socket *sock, 678 struct msghdr *m, size_t total_len) 679 { 680 struct sock *sk = sock->sk; 681 struct tipc_port *tport = tipc_sk_port(sk); 682 struct msghdr my_msg; 683 struct iovec my_iov; 684 struct iovec *curr_iov; 685 int curr_iovlen; 686 char __user *curr_start; 687 u32 hdr_size; 688 int curr_left; 689 int bytes_to_send; 690 int bytes_sent; 691 int res; 692 693 lock_sock(sk); 694 695 /* Handle special cases where there is no connection */ 696 if (unlikely(sock->state != SS_CONNECTED)) { 697 if (sock->state == SS_UNCONNECTED) { 698 res = send_packet(NULL, sock, m, total_len); 699 goto exit; 700 } else if (sock->state == SS_DISCONNECTING) { 701 res = -EPIPE; 702 goto exit; 703 } else { 704 res = -ENOTCONN; 705 goto exit; 706 } 707 } 708 709 if (unlikely(m->msg_name)) { 710 res = -EISCONN; 711 goto exit; 712 } 713 714 if ((total_len > (unsigned int)INT_MAX) || 715 (m->msg_iovlen > (unsigned int)INT_MAX)) { 716 res = -EMSGSIZE; 717 goto exit; 718 } 719 720 /* 721 * Send each iovec entry using one or more messages 722 * 723 * Note: This algorithm is good for the most likely case 724 * (i.e. one large iovec entry), but could be improved to pass sets 725 * of small iovec entries into send_packet(). 726 */ 727 curr_iov = m->msg_iov; 728 curr_iovlen = m->msg_iovlen; 729 my_msg.msg_iov = &my_iov; 730 my_msg.msg_iovlen = 1; 731 my_msg.msg_flags = m->msg_flags; 732 my_msg.msg_name = NULL; 733 bytes_sent = 0; 734 735 hdr_size = msg_hdr_sz(&tport->phdr); 736 737 while (curr_iovlen--) { 738 curr_start = curr_iov->iov_base; 739 curr_left = curr_iov->iov_len; 740 741 while (curr_left) { 742 bytes_to_send = tport->max_pkt - hdr_size; 743 if (bytes_to_send > TIPC_MAX_USER_MSG_SIZE) 744 bytes_to_send = TIPC_MAX_USER_MSG_SIZE; 745 if (curr_left < bytes_to_send) 746 bytes_to_send = curr_left; 747 my_iov.iov_base = curr_start; 748 my_iov.iov_len = bytes_to_send; 749 res = send_packet(NULL, sock, &my_msg, bytes_to_send); 750 if (res < 0) { 751 if (bytes_sent) 752 res = bytes_sent; 753 goto exit; 754 } 755 curr_left -= bytes_to_send; 756 curr_start += bytes_to_send; 757 bytes_sent += bytes_to_send; 758 } 759 760 curr_iov++; 761 } 762 res = bytes_sent; 763 exit: 764 release_sock(sk); 765 return res; 766 } 767 768 /** 769 * auto_connect - complete connection setup to a remote port 770 * @sock: socket structure 771 * @msg: peer's response message 772 * 773 * Returns 0 on success, errno otherwise 774 */ 775 static int auto_connect(struct socket *sock, struct tipc_msg *msg) 776 { 777 struct tipc_sock *tsock = tipc_sk(sock->sk); 778 struct tipc_port *p_ptr; 779 780 tsock->peer_name.ref = msg_origport(msg); 781 tsock->peer_name.node = msg_orignode(msg); 782 p_ptr = tipc_port_deref(tsock->p->ref); 783 if (!p_ptr) 784 return -EINVAL; 785 786 __tipc_connect(tsock->p->ref, p_ptr, &tsock->peer_name); 787 788 if (msg_importance(msg) > TIPC_CRITICAL_IMPORTANCE) 789 return -EINVAL; 790 msg_set_importance(&p_ptr->phdr, (u32)msg_importance(msg)); 791 sock->state = SS_CONNECTED; 792 return 0; 793 } 794 795 /** 796 * set_orig_addr - capture sender's address for received message 797 * @m: descriptor for message info 798 * @msg: received message header 799 * 800 * Note: Address is not captured if not requested by receiver. 801 */ 802 static void set_orig_addr(struct msghdr *m, struct tipc_msg *msg) 803 { 804 struct sockaddr_tipc *addr = (struct sockaddr_tipc *)m->msg_name; 805 806 if (addr) { 807 addr->family = AF_TIPC; 808 addr->addrtype = TIPC_ADDR_ID; 809 addr->addr.id.ref = msg_origport(msg); 810 addr->addr.id.node = msg_orignode(msg); 811 addr->addr.name.domain = 0; /* could leave uninitialized */ 812 addr->scope = 0; /* could leave uninitialized */ 813 m->msg_namelen = sizeof(struct sockaddr_tipc); 814 } 815 } 816 817 /** 818 * anc_data_recv - optionally capture ancillary data for received message 819 * @m: descriptor for message info 820 * @msg: received message header 821 * @tport: TIPC port associated with message 822 * 823 * Note: Ancillary data is not captured if not requested by receiver. 824 * 825 * Returns 0 if successful, otherwise errno 826 */ 827 static int anc_data_recv(struct msghdr *m, struct tipc_msg *msg, 828 struct tipc_port *tport) 829 { 830 u32 anc_data[3]; 831 u32 err; 832 u32 dest_type; 833 int has_name; 834 int res; 835 836 if (likely(m->msg_controllen == 0)) 837 return 0; 838 839 /* Optionally capture errored message object(s) */ 840 err = msg ? msg_errcode(msg) : 0; 841 if (unlikely(err)) { 842 anc_data[0] = err; 843 anc_data[1] = msg_data_sz(msg); 844 res = put_cmsg(m, SOL_TIPC, TIPC_ERRINFO, 8, anc_data); 845 if (res) 846 return res; 847 if (anc_data[1]) { 848 res = put_cmsg(m, SOL_TIPC, TIPC_RETDATA, anc_data[1], 849 msg_data(msg)); 850 if (res) 851 return res; 852 } 853 } 854 855 /* Optionally capture message destination object */ 856 dest_type = msg ? msg_type(msg) : TIPC_DIRECT_MSG; 857 switch (dest_type) { 858 case TIPC_NAMED_MSG: 859 has_name = 1; 860 anc_data[0] = msg_nametype(msg); 861 anc_data[1] = msg_namelower(msg); 862 anc_data[2] = msg_namelower(msg); 863 break; 864 case TIPC_MCAST_MSG: 865 has_name = 1; 866 anc_data[0] = msg_nametype(msg); 867 anc_data[1] = msg_namelower(msg); 868 anc_data[2] = msg_nameupper(msg); 869 break; 870 case TIPC_CONN_MSG: 871 has_name = (tport->conn_type != 0); 872 anc_data[0] = tport->conn_type; 873 anc_data[1] = tport->conn_instance; 874 anc_data[2] = tport->conn_instance; 875 break; 876 default: 877 has_name = 0; 878 } 879 if (has_name) { 880 res = put_cmsg(m, SOL_TIPC, TIPC_DESTNAME, 12, anc_data); 881 if (res) 882 return res; 883 } 884 885 return 0; 886 } 887 888 /** 889 * recv_msg - receive packet-oriented message 890 * @iocb: (unused) 891 * @m: descriptor for message info 892 * @buf_len: total size of user buffer area 893 * @flags: receive flags 894 * 895 * Used for SOCK_DGRAM, SOCK_RDM, and SOCK_SEQPACKET messages. 896 * If the complete message doesn't fit in user area, truncate it. 897 * 898 * Returns size of returned message data, errno otherwise 899 */ 900 static int recv_msg(struct kiocb *iocb, struct socket *sock, 901 struct msghdr *m, size_t buf_len, int flags) 902 { 903 struct sock *sk = sock->sk; 904 struct tipc_port *tport = tipc_sk_port(sk); 905 struct sk_buff *buf; 906 struct tipc_msg *msg; 907 long timeout; 908 unsigned int sz; 909 u32 err; 910 int res; 911 912 /* Catch invalid receive requests */ 913 if (unlikely(!buf_len)) 914 return -EINVAL; 915 916 lock_sock(sk); 917 918 if (unlikely(sock->state == SS_UNCONNECTED)) { 919 res = -ENOTCONN; 920 goto exit; 921 } 922 923 timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); 924 restart: 925 926 /* Look for a message in receive queue; wait if necessary */ 927 while (skb_queue_empty(&sk->sk_receive_queue)) { 928 if (sock->state == SS_DISCONNECTING) { 929 res = -ENOTCONN; 930 goto exit; 931 } 932 if (timeout <= 0L) { 933 res = timeout ? timeout : -EWOULDBLOCK; 934 goto exit; 935 } 936 release_sock(sk); 937 timeout = wait_event_interruptible_timeout(*sk_sleep(sk), 938 tipc_rx_ready(sock), 939 timeout); 940 lock_sock(sk); 941 } 942 943 /* Look at first message in receive queue */ 944 buf = skb_peek(&sk->sk_receive_queue); 945 msg = buf_msg(buf); 946 sz = msg_data_sz(msg); 947 err = msg_errcode(msg); 948 949 /* Discard an empty non-errored message & try again */ 950 if ((!sz) && (!err)) { 951 advance_rx_queue(sk); 952 goto restart; 953 } 954 955 /* Capture sender's address (optional) */ 956 set_orig_addr(m, msg); 957 958 /* Capture ancillary data (optional) */ 959 res = anc_data_recv(m, msg, tport); 960 if (res) 961 goto exit; 962 963 /* Capture message data (if valid) & compute return value (always) */ 964 if (!err) { 965 if (unlikely(buf_len < sz)) { 966 sz = buf_len; 967 m->msg_flags |= MSG_TRUNC; 968 } 969 res = skb_copy_datagram_iovec(buf, msg_hdr_sz(msg), 970 m->msg_iov, sz); 971 if (res) 972 goto exit; 973 res = sz; 974 } else { 975 if ((sock->state == SS_READY) || 976 ((err == TIPC_CONN_SHUTDOWN) || m->msg_control)) 977 res = 0; 978 else 979 res = -ECONNRESET; 980 } 981 982 /* Consume received message (optional) */ 983 if (likely(!(flags & MSG_PEEK))) { 984 if ((sock->state != SS_READY) && 985 (++tport->conn_unacked >= TIPC_FLOW_CONTROL_WIN)) 986 tipc_acknowledge(tport->ref, tport->conn_unacked); 987 advance_rx_queue(sk); 988 } 989 exit: 990 release_sock(sk); 991 return res; 992 } 993 994 /** 995 * recv_stream - receive stream-oriented data 996 * @iocb: (unused) 997 * @m: descriptor for message info 998 * @buf_len: total size of user buffer area 999 * @flags: receive flags 1000 * 1001 * Used for SOCK_STREAM messages only. If not enough data is available 1002 * will optionally wait for more; never truncates data. 1003 * 1004 * Returns size of returned message data, errno otherwise 1005 */ 1006 static int recv_stream(struct kiocb *iocb, struct socket *sock, 1007 struct msghdr *m, size_t buf_len, int flags) 1008 { 1009 struct sock *sk = sock->sk; 1010 struct tipc_port *tport = tipc_sk_port(sk); 1011 struct sk_buff *buf; 1012 struct tipc_msg *msg; 1013 long timeout; 1014 unsigned int sz; 1015 int sz_to_copy, target, needed; 1016 int sz_copied = 0; 1017 u32 err; 1018 int res = 0; 1019 1020 /* Catch invalid receive attempts */ 1021 if (unlikely(!buf_len)) 1022 return -EINVAL; 1023 1024 lock_sock(sk); 1025 1026 if (unlikely((sock->state == SS_UNCONNECTED) || 1027 (sock->state == SS_CONNECTING))) { 1028 res = -ENOTCONN; 1029 goto exit; 1030 } 1031 1032 target = sock_rcvlowat(sk, flags & MSG_WAITALL, buf_len); 1033 timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); 1034 1035 restart: 1036 /* Look for a message in receive queue; wait if necessary */ 1037 while (skb_queue_empty(&sk->sk_receive_queue)) { 1038 if (sock->state == SS_DISCONNECTING) { 1039 res = -ENOTCONN; 1040 goto exit; 1041 } 1042 if (timeout <= 0L) { 1043 res = timeout ? timeout : -EWOULDBLOCK; 1044 goto exit; 1045 } 1046 release_sock(sk); 1047 timeout = wait_event_interruptible_timeout(*sk_sleep(sk), 1048 tipc_rx_ready(sock), 1049 timeout); 1050 lock_sock(sk); 1051 } 1052 1053 /* Look at first message in receive queue */ 1054 buf = skb_peek(&sk->sk_receive_queue); 1055 msg = buf_msg(buf); 1056 sz = msg_data_sz(msg); 1057 err = msg_errcode(msg); 1058 1059 /* Discard an empty non-errored message & try again */ 1060 if ((!sz) && (!err)) { 1061 advance_rx_queue(sk); 1062 goto restart; 1063 } 1064 1065 /* Optionally capture sender's address & ancillary data of first msg */ 1066 if (sz_copied == 0) { 1067 set_orig_addr(m, msg); 1068 res = anc_data_recv(m, msg, tport); 1069 if (res) 1070 goto exit; 1071 } 1072 1073 /* Capture message data (if valid) & compute return value (always) */ 1074 if (!err) { 1075 u32 offset = (u32)(unsigned long)(TIPC_SKB_CB(buf)->handle); 1076 1077 sz -= offset; 1078 needed = (buf_len - sz_copied); 1079 sz_to_copy = (sz <= needed) ? sz : needed; 1080 1081 res = skb_copy_datagram_iovec(buf, msg_hdr_sz(msg) + offset, 1082 m->msg_iov, sz_to_copy); 1083 if (res) 1084 goto exit; 1085 1086 sz_copied += sz_to_copy; 1087 1088 if (sz_to_copy < sz) { 1089 if (!(flags & MSG_PEEK)) 1090 TIPC_SKB_CB(buf)->handle = 1091 (void *)(unsigned long)(offset + sz_to_copy); 1092 goto exit; 1093 } 1094 } else { 1095 if (sz_copied != 0) 1096 goto exit; /* can't add error msg to valid data */ 1097 1098 if ((err == TIPC_CONN_SHUTDOWN) || m->msg_control) 1099 res = 0; 1100 else 1101 res = -ECONNRESET; 1102 } 1103 1104 /* Consume received message (optional) */ 1105 if (likely(!(flags & MSG_PEEK))) { 1106 if (unlikely(++tport->conn_unacked >= TIPC_FLOW_CONTROL_WIN)) 1107 tipc_acknowledge(tport->ref, tport->conn_unacked); 1108 advance_rx_queue(sk); 1109 } 1110 1111 /* Loop around if more data is required */ 1112 if ((sz_copied < buf_len) && /* didn't get all requested data */ 1113 (!skb_queue_empty(&sk->sk_receive_queue) || 1114 (sz_copied < target)) && /* and more is ready or required */ 1115 (!(flags & MSG_PEEK)) && /* and aren't just peeking at data */ 1116 (!err)) /* and haven't reached a FIN */ 1117 goto restart; 1118 1119 exit: 1120 release_sock(sk); 1121 return sz_copied ? sz_copied : res; 1122 } 1123 1124 /** 1125 * tipc_write_space - wake up thread if port congestion is released 1126 * @sk: socket 1127 */ 1128 static void tipc_write_space(struct sock *sk) 1129 { 1130 struct socket_wq *wq; 1131 1132 rcu_read_lock(); 1133 wq = rcu_dereference(sk->sk_wq); 1134 if (wq_has_sleeper(wq)) 1135 wake_up_interruptible_sync_poll(&wq->wait, POLLOUT | 1136 POLLWRNORM | POLLWRBAND); 1137 rcu_read_unlock(); 1138 } 1139 1140 /** 1141 * tipc_data_ready - wake up threads to indicate messages have been received 1142 * @sk: socket 1143 * @len: the length of messages 1144 */ 1145 static void tipc_data_ready(struct sock *sk, int len) 1146 { 1147 struct socket_wq *wq; 1148 1149 rcu_read_lock(); 1150 wq = rcu_dereference(sk->sk_wq); 1151 if (wq_has_sleeper(wq)) 1152 wake_up_interruptible_sync_poll(&wq->wait, POLLIN | 1153 POLLRDNORM | POLLRDBAND); 1154 rcu_read_unlock(); 1155 } 1156 1157 /** 1158 * rx_queue_full - determine if receive queue can accept another message 1159 * @msg: message to be added to queue 1160 * @queue_size: current size of queue 1161 * @base: nominal maximum size of queue 1162 * 1163 * Returns 1 if queue is unable to accept message, 0 otherwise 1164 */ 1165 static int rx_queue_full(struct tipc_msg *msg, u32 queue_size, u32 base) 1166 { 1167 u32 threshold; 1168 u32 imp = msg_importance(msg); 1169 1170 if (imp == TIPC_LOW_IMPORTANCE) 1171 threshold = base; 1172 else if (imp == TIPC_MEDIUM_IMPORTANCE) 1173 threshold = base * 2; 1174 else if (imp == TIPC_HIGH_IMPORTANCE) 1175 threshold = base * 100; 1176 else 1177 return 0; 1178 1179 if (msg_connected(msg)) 1180 threshold *= 4; 1181 1182 return queue_size >= threshold; 1183 } 1184 1185 /** 1186 * filter_connect - Handle all incoming messages for a connection-based socket 1187 * @tsock: TIPC socket 1188 * @msg: message 1189 * 1190 * Returns TIPC error status code and socket error status code 1191 * once it encounters some errors 1192 */ 1193 static u32 filter_connect(struct tipc_sock *tsock, struct sk_buff **buf) 1194 { 1195 struct socket *sock = tsock->sk.sk_socket; 1196 struct tipc_msg *msg = buf_msg(*buf); 1197 struct sock *sk = &tsock->sk; 1198 u32 retval = TIPC_ERR_NO_PORT; 1199 int res; 1200 1201 if (msg_mcast(msg)) 1202 return retval; 1203 1204 switch ((int)sock->state) { 1205 case SS_CONNECTED: 1206 /* Accept only connection-based messages sent by peer */ 1207 if (msg_connected(msg) && tipc_port_peer_msg(tsock->p, msg)) { 1208 if (unlikely(msg_errcode(msg))) { 1209 sock->state = SS_DISCONNECTING; 1210 __tipc_disconnect(tsock->p); 1211 } 1212 retval = TIPC_OK; 1213 } 1214 break; 1215 case SS_CONNECTING: 1216 /* Accept only ACK or NACK message */ 1217 if (unlikely(msg_errcode(msg))) { 1218 sock->state = SS_DISCONNECTING; 1219 sk->sk_err = -ECONNREFUSED; 1220 retval = TIPC_OK; 1221 break; 1222 } 1223 1224 if (unlikely(!msg_connected(msg))) 1225 break; 1226 1227 res = auto_connect(sock, msg); 1228 if (res) { 1229 sock->state = SS_DISCONNECTING; 1230 sk->sk_err = res; 1231 retval = TIPC_OK; 1232 break; 1233 } 1234 1235 /* If an incoming message is an 'ACK-', it should be 1236 * discarded here because it doesn't contain useful 1237 * data. In addition, we should try to wake up 1238 * connect() routine if sleeping. 1239 */ 1240 if (msg_data_sz(msg) == 0) { 1241 kfree_skb(*buf); 1242 *buf = NULL; 1243 if (waitqueue_active(sk_sleep(sk))) 1244 wake_up_interruptible(sk_sleep(sk)); 1245 } 1246 retval = TIPC_OK; 1247 break; 1248 case SS_LISTENING: 1249 case SS_UNCONNECTED: 1250 /* Accept only SYN message */ 1251 if (!msg_connected(msg) && !(msg_errcode(msg))) 1252 retval = TIPC_OK; 1253 break; 1254 case SS_DISCONNECTING: 1255 break; 1256 default: 1257 pr_err("Unknown socket state %u\n", sock->state); 1258 } 1259 return retval; 1260 } 1261 1262 /** 1263 * filter_rcv - validate incoming message 1264 * @sk: socket 1265 * @buf: message 1266 * 1267 * Enqueues message on receive queue if acceptable; optionally handles 1268 * disconnect indication for a connected socket. 1269 * 1270 * Called with socket lock already taken; port lock may also be taken. 1271 * 1272 * Returns TIPC error status code (TIPC_OK if message is not to be rejected) 1273 */ 1274 static u32 filter_rcv(struct sock *sk, struct sk_buff *buf) 1275 { 1276 struct socket *sock = sk->sk_socket; 1277 struct tipc_msg *msg = buf_msg(buf); 1278 u32 recv_q_len; 1279 u32 res = TIPC_OK; 1280 1281 /* Reject message if it is wrong sort of message for socket */ 1282 if (msg_type(msg) > TIPC_DIRECT_MSG) 1283 return TIPC_ERR_NO_PORT; 1284 1285 if (sock->state == SS_READY) { 1286 if (msg_connected(msg)) 1287 return TIPC_ERR_NO_PORT; 1288 } else { 1289 res = filter_connect(tipc_sk(sk), &buf); 1290 if (res != TIPC_OK || buf == NULL) 1291 return res; 1292 } 1293 1294 /* Reject message if there isn't room to queue it */ 1295 recv_q_len = skb_queue_len(&sk->sk_receive_queue); 1296 if (unlikely(recv_q_len >= (OVERLOAD_LIMIT_BASE / 2))) { 1297 if (rx_queue_full(msg, recv_q_len, OVERLOAD_LIMIT_BASE / 2)) 1298 return TIPC_ERR_OVERLOAD; 1299 } 1300 1301 /* Enqueue message (finally!) */ 1302 TIPC_SKB_CB(buf)->handle = 0; 1303 __skb_queue_tail(&sk->sk_receive_queue, buf); 1304 1305 sk->sk_data_ready(sk, 0); 1306 return TIPC_OK; 1307 } 1308 1309 /** 1310 * backlog_rcv - handle incoming message from backlog queue 1311 * @sk: socket 1312 * @buf: message 1313 * 1314 * Caller must hold socket lock, but not port lock. 1315 * 1316 * Returns 0 1317 */ 1318 static int backlog_rcv(struct sock *sk, struct sk_buff *buf) 1319 { 1320 u32 res; 1321 1322 res = filter_rcv(sk, buf); 1323 if (res) 1324 tipc_reject_msg(buf, res); 1325 return 0; 1326 } 1327 1328 /** 1329 * dispatch - handle incoming message 1330 * @tport: TIPC port that received message 1331 * @buf: message 1332 * 1333 * Called with port lock already taken. 1334 * 1335 * Returns TIPC error status code (TIPC_OK if message is not to be rejected) 1336 */ 1337 static u32 dispatch(struct tipc_port *tport, struct sk_buff *buf) 1338 { 1339 struct sock *sk = (struct sock *)tport->usr_handle; 1340 u32 res; 1341 1342 /* 1343 * Process message if socket is unlocked; otherwise add to backlog queue 1344 * 1345 * This code is based on sk_receive_skb(), but must be distinct from it 1346 * since a TIPC-specific filter/reject mechanism is utilized 1347 */ 1348 bh_lock_sock(sk); 1349 if (!sock_owned_by_user(sk)) { 1350 res = filter_rcv(sk, buf); 1351 } else { 1352 if (sk_add_backlog(sk, buf, sk->sk_rcvbuf)) 1353 res = TIPC_ERR_OVERLOAD; 1354 else 1355 res = TIPC_OK; 1356 } 1357 bh_unlock_sock(sk); 1358 1359 return res; 1360 } 1361 1362 /** 1363 * wakeupdispatch - wake up port after congestion 1364 * @tport: port to wakeup 1365 * 1366 * Called with port lock already taken. 1367 */ 1368 static void wakeupdispatch(struct tipc_port *tport) 1369 { 1370 struct sock *sk = (struct sock *)tport->usr_handle; 1371 1372 sk->sk_write_space(sk); 1373 } 1374 1375 /** 1376 * connect - establish a connection to another TIPC port 1377 * @sock: socket structure 1378 * @dest: socket address for destination port 1379 * @destlen: size of socket address data structure 1380 * @flags: file-related flags associated with socket 1381 * 1382 * Returns 0 on success, errno otherwise 1383 */ 1384 static int connect(struct socket *sock, struct sockaddr *dest, int destlen, 1385 int flags) 1386 { 1387 struct sock *sk = sock->sk; 1388 struct sockaddr_tipc *dst = (struct sockaddr_tipc *)dest; 1389 struct msghdr m = {NULL,}; 1390 unsigned int timeout; 1391 int res; 1392 1393 lock_sock(sk); 1394 1395 /* For now, TIPC does not allow use of connect() with DGRAM/RDM types */ 1396 if (sock->state == SS_READY) { 1397 res = -EOPNOTSUPP; 1398 goto exit; 1399 } 1400 1401 /* 1402 * Reject connection attempt using multicast address 1403 * 1404 * Note: send_msg() validates the rest of the address fields, 1405 * so there's no need to do it here 1406 */ 1407 if (dst->addrtype == TIPC_ADDR_MCAST) { 1408 res = -EINVAL; 1409 goto exit; 1410 } 1411 1412 timeout = (flags & O_NONBLOCK) ? 0 : tipc_sk(sk)->conn_timeout; 1413 1414 switch (sock->state) { 1415 case SS_UNCONNECTED: 1416 /* Send a 'SYN-' to destination */ 1417 m.msg_name = dest; 1418 m.msg_namelen = destlen; 1419 1420 /* If connect is in non-blocking case, set MSG_DONTWAIT to 1421 * indicate send_msg() is never blocked. 1422 */ 1423 if (!timeout) 1424 m.msg_flags = MSG_DONTWAIT; 1425 1426 res = send_msg(NULL, sock, &m, 0); 1427 if ((res < 0) && (res != -EWOULDBLOCK)) 1428 goto exit; 1429 1430 /* Just entered SS_CONNECTING state; the only 1431 * difference is that return value in non-blocking 1432 * case is EINPROGRESS, rather than EALREADY. 1433 */ 1434 res = -EINPROGRESS; 1435 break; 1436 case SS_CONNECTING: 1437 res = -EALREADY; 1438 break; 1439 case SS_CONNECTED: 1440 res = -EISCONN; 1441 break; 1442 default: 1443 res = -EINVAL; 1444 goto exit; 1445 } 1446 1447 if (sock->state == SS_CONNECTING) { 1448 if (!timeout) 1449 goto exit; 1450 1451 /* Wait until an 'ACK' or 'RST' arrives, or a timeout occurs */ 1452 release_sock(sk); 1453 res = wait_event_interruptible_timeout(*sk_sleep(sk), 1454 sock->state != SS_CONNECTING, 1455 timeout ? (long)msecs_to_jiffies(timeout) 1456 : MAX_SCHEDULE_TIMEOUT); 1457 lock_sock(sk); 1458 if (res <= 0) { 1459 if (res == 0) 1460 res = -ETIMEDOUT; 1461 else 1462 ; /* leave "res" unchanged */ 1463 goto exit; 1464 } 1465 } 1466 1467 if (unlikely(sock->state == SS_DISCONNECTING)) 1468 res = sock_error(sk); 1469 else 1470 res = 0; 1471 1472 exit: 1473 release_sock(sk); 1474 return res; 1475 } 1476 1477 /** 1478 * listen - allow socket to listen for incoming connections 1479 * @sock: socket structure 1480 * @len: (unused) 1481 * 1482 * Returns 0 on success, errno otherwise 1483 */ 1484 static int listen(struct socket *sock, int len) 1485 { 1486 struct sock *sk = sock->sk; 1487 int res; 1488 1489 lock_sock(sk); 1490 1491 if (sock->state != SS_UNCONNECTED) 1492 res = -EINVAL; 1493 else { 1494 sock->state = SS_LISTENING; 1495 res = 0; 1496 } 1497 1498 release_sock(sk); 1499 return res; 1500 } 1501 1502 /** 1503 * accept - wait for connection request 1504 * @sock: listening socket 1505 * @newsock: new socket that is to be connected 1506 * @flags: file-related flags associated with socket 1507 * 1508 * Returns 0 on success, errno otherwise 1509 */ 1510 static int accept(struct socket *sock, struct socket *new_sock, int flags) 1511 { 1512 struct sock *new_sk, *sk = sock->sk; 1513 struct sk_buff *buf; 1514 struct tipc_sock *new_tsock; 1515 struct tipc_port *new_tport; 1516 struct tipc_msg *msg; 1517 u32 new_ref; 1518 1519 int res; 1520 1521 lock_sock(sk); 1522 1523 if (sock->state != SS_LISTENING) { 1524 res = -EINVAL; 1525 goto exit; 1526 } 1527 1528 while (skb_queue_empty(&sk->sk_receive_queue)) { 1529 if (flags & O_NONBLOCK) { 1530 res = -EWOULDBLOCK; 1531 goto exit; 1532 } 1533 release_sock(sk); 1534 res = wait_event_interruptible(*sk_sleep(sk), 1535 (!skb_queue_empty(&sk->sk_receive_queue))); 1536 lock_sock(sk); 1537 if (res) 1538 goto exit; 1539 } 1540 1541 buf = skb_peek(&sk->sk_receive_queue); 1542 1543 res = tipc_create(sock_net(sock->sk), new_sock, 0, 0); 1544 if (res) 1545 goto exit; 1546 1547 new_sk = new_sock->sk; 1548 new_tsock = tipc_sk(new_sk); 1549 new_tport = new_tsock->p; 1550 new_ref = new_tport->ref; 1551 msg = buf_msg(buf); 1552 1553 /* we lock on new_sk; but lockdep sees the lock on sk */ 1554 lock_sock_nested(new_sk, SINGLE_DEPTH_NESTING); 1555 1556 /* 1557 * Reject any stray messages received by new socket 1558 * before the socket lock was taken (very, very unlikely) 1559 */ 1560 reject_rx_queue(new_sk); 1561 1562 /* Connect new socket to it's peer */ 1563 new_tsock->peer_name.ref = msg_origport(msg); 1564 new_tsock->peer_name.node = msg_orignode(msg); 1565 tipc_connect(new_ref, &new_tsock->peer_name); 1566 new_sock->state = SS_CONNECTED; 1567 1568 tipc_set_portimportance(new_ref, msg_importance(msg)); 1569 if (msg_named(msg)) { 1570 new_tport->conn_type = msg_nametype(msg); 1571 new_tport->conn_instance = msg_nameinst(msg); 1572 } 1573 1574 /* 1575 * Respond to 'SYN-' by discarding it & returning 'ACK'-. 1576 * Respond to 'SYN+' by queuing it on new socket. 1577 */ 1578 if (!msg_data_sz(msg)) { 1579 struct msghdr m = {NULL,}; 1580 1581 advance_rx_queue(sk); 1582 send_packet(NULL, new_sock, &m, 0); 1583 } else { 1584 __skb_dequeue(&sk->sk_receive_queue); 1585 __skb_queue_head(&new_sk->sk_receive_queue, buf); 1586 } 1587 release_sock(new_sk); 1588 1589 exit: 1590 release_sock(sk); 1591 return res; 1592 } 1593 1594 /** 1595 * shutdown - shutdown socket connection 1596 * @sock: socket structure 1597 * @how: direction to close (must be SHUT_RDWR) 1598 * 1599 * Terminates connection (if necessary), then purges socket's receive queue. 1600 * 1601 * Returns 0 on success, errno otherwise 1602 */ 1603 static int shutdown(struct socket *sock, int how) 1604 { 1605 struct sock *sk = sock->sk; 1606 struct tipc_port *tport = tipc_sk_port(sk); 1607 struct sk_buff *buf; 1608 int res; 1609 1610 if (how != SHUT_RDWR) 1611 return -EINVAL; 1612 1613 lock_sock(sk); 1614 1615 switch (sock->state) { 1616 case SS_CONNECTING: 1617 case SS_CONNECTED: 1618 1619 restart: 1620 /* Disconnect and send a 'FIN+' or 'FIN-' message to peer */ 1621 buf = __skb_dequeue(&sk->sk_receive_queue); 1622 if (buf) { 1623 if (TIPC_SKB_CB(buf)->handle != 0) { 1624 kfree_skb(buf); 1625 goto restart; 1626 } 1627 tipc_disconnect(tport->ref); 1628 tipc_reject_msg(buf, TIPC_CONN_SHUTDOWN); 1629 } else { 1630 tipc_shutdown(tport->ref); 1631 } 1632 1633 sock->state = SS_DISCONNECTING; 1634 1635 /* fall through */ 1636 1637 case SS_DISCONNECTING: 1638 1639 /* Discard any unreceived messages */ 1640 discard_rx_queue(sk); 1641 1642 /* Wake up anyone sleeping in poll */ 1643 sk->sk_state_change(sk); 1644 res = 0; 1645 break; 1646 1647 default: 1648 res = -ENOTCONN; 1649 } 1650 1651 release_sock(sk); 1652 return res; 1653 } 1654 1655 /** 1656 * setsockopt - set socket option 1657 * @sock: socket structure 1658 * @lvl: option level 1659 * @opt: option identifier 1660 * @ov: pointer to new option value 1661 * @ol: length of option value 1662 * 1663 * For stream sockets only, accepts and ignores all IPPROTO_TCP options 1664 * (to ease compatibility). 1665 * 1666 * Returns 0 on success, errno otherwise 1667 */ 1668 static int setsockopt(struct socket *sock, 1669 int lvl, int opt, char __user *ov, unsigned int ol) 1670 { 1671 struct sock *sk = sock->sk; 1672 struct tipc_port *tport = tipc_sk_port(sk); 1673 u32 value; 1674 int res; 1675 1676 if ((lvl == IPPROTO_TCP) && (sock->type == SOCK_STREAM)) 1677 return 0; 1678 if (lvl != SOL_TIPC) 1679 return -ENOPROTOOPT; 1680 if (ol < sizeof(value)) 1681 return -EINVAL; 1682 res = get_user(value, (u32 __user *)ov); 1683 if (res) 1684 return res; 1685 1686 lock_sock(sk); 1687 1688 switch (opt) { 1689 case TIPC_IMPORTANCE: 1690 res = tipc_set_portimportance(tport->ref, value); 1691 break; 1692 case TIPC_SRC_DROPPABLE: 1693 if (sock->type != SOCK_STREAM) 1694 res = tipc_set_portunreliable(tport->ref, value); 1695 else 1696 res = -ENOPROTOOPT; 1697 break; 1698 case TIPC_DEST_DROPPABLE: 1699 res = tipc_set_portunreturnable(tport->ref, value); 1700 break; 1701 case TIPC_CONN_TIMEOUT: 1702 tipc_sk(sk)->conn_timeout = value; 1703 /* no need to set "res", since already 0 at this point */ 1704 break; 1705 default: 1706 res = -EINVAL; 1707 } 1708 1709 release_sock(sk); 1710 1711 return res; 1712 } 1713 1714 /** 1715 * getsockopt - get socket option 1716 * @sock: socket structure 1717 * @lvl: option level 1718 * @opt: option identifier 1719 * @ov: receptacle for option value 1720 * @ol: receptacle for length of option value 1721 * 1722 * For stream sockets only, returns 0 length result for all IPPROTO_TCP options 1723 * (to ease compatibility). 1724 * 1725 * Returns 0 on success, errno otherwise 1726 */ 1727 static int getsockopt(struct socket *sock, 1728 int lvl, int opt, char __user *ov, int __user *ol) 1729 { 1730 struct sock *sk = sock->sk; 1731 struct tipc_port *tport = tipc_sk_port(sk); 1732 int len; 1733 u32 value; 1734 int res; 1735 1736 if ((lvl == IPPROTO_TCP) && (sock->type == SOCK_STREAM)) 1737 return put_user(0, ol); 1738 if (lvl != SOL_TIPC) 1739 return -ENOPROTOOPT; 1740 res = get_user(len, ol); 1741 if (res) 1742 return res; 1743 1744 lock_sock(sk); 1745 1746 switch (opt) { 1747 case TIPC_IMPORTANCE: 1748 res = tipc_portimportance(tport->ref, &value); 1749 break; 1750 case TIPC_SRC_DROPPABLE: 1751 res = tipc_portunreliable(tport->ref, &value); 1752 break; 1753 case TIPC_DEST_DROPPABLE: 1754 res = tipc_portunreturnable(tport->ref, &value); 1755 break; 1756 case TIPC_CONN_TIMEOUT: 1757 value = tipc_sk(sk)->conn_timeout; 1758 /* no need to set "res", since already 0 at this point */ 1759 break; 1760 case TIPC_NODE_RECVQ_DEPTH: 1761 value = 0; /* was tipc_queue_size, now obsolete */ 1762 break; 1763 case TIPC_SOCK_RECVQ_DEPTH: 1764 value = skb_queue_len(&sk->sk_receive_queue); 1765 break; 1766 default: 1767 res = -EINVAL; 1768 } 1769 1770 release_sock(sk); 1771 1772 if (res) 1773 return res; /* "get" failed */ 1774 1775 if (len < sizeof(value)) 1776 return -EINVAL; 1777 1778 if (copy_to_user(ov, &value, sizeof(value))) 1779 return -EFAULT; 1780 1781 return put_user(sizeof(value), ol); 1782 } 1783 1784 /* Protocol switches for the various types of TIPC sockets */ 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 = sock_no_accept, 1794 .getname = get_name, 1795 .poll = poll, 1796 .ioctl = sock_no_ioctl, 1797 .listen = sock_no_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 pr_err("Failed to register TIPC protocol type\n"); 1873 goto out; 1874 } 1875 1876 res = sock_register(&tipc_family_ops); 1877 if (res) { 1878 pr_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 void tipc_socket_stop(void) 1892 { 1893 if (!sockets_enabled) 1894 return; 1895 1896 sockets_enabled = 0; 1897 sock_unregister(tipc_family_ops.family); 1898 proto_unregister(&tipc_proto); 1899 } 1900