1 /*- 2 * Copyright (c) 1982, 1986, 1988, 1990, 1993 3 * The Regents of the University of California. All rights reserved. 4 * Copyright (c) 2004 The FreeBSD Foundation 5 * Copyright (c) 2004-2006 Robert N. M. Watson 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 4. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)uipc_socket.c 8.3 (Berkeley) 4/15/94 32 */ 33 34 /* 35 * Comments on the socket life cycle: 36 * 37 * soalloc() sets of socket layer state for a socket, called only by 38 * socreate() and sonewconn(). Socket layer private. 39 * 40 * sodealloc() tears down socket layer state for a socket, called only by 41 * sofree() and sonewconn(). Socket layer private. 42 * 43 * pru_attach() associates protocol layer state with an allocated socket; 44 * called only once, may fail, aborting socket allocation. This is called 45 * from socreate() and sonewconn(). Socket layer private. 46 * 47 * pru_detach() disassociates protocol layer state from an attached socket, 48 * and will be called exactly once for sockets in which pru_attach() has 49 * been successfully called. If pru_attach() returned an error, 50 * pru_detach() will not be called. Socket layer private. 51 * 52 * pru_abort() and pru_close() notify the protocol layer that the last 53 * consumer of a socket is starting to tear down the socket, and that the 54 * protocol should terminate the connection. Historically, pru_abort() also 55 * detached protocol state from the socket state, but this is no longer the 56 * case. 57 * 58 * socreate() creates a socket and attaches protocol state. This is a public 59 * interface that may be used by socket layer consumers to create new 60 * sockets. 61 * 62 * sonewconn() creates a socket and attaches protocol state. This is a 63 * public interface that may be used by protocols to create new sockets when 64 * a new connection is received and will be available for accept() on a 65 * listen socket. 66 * 67 * soclose() destroys a socket after possibly waiting for it to disconnect. 68 * This is a public interface that socket consumers should use to close and 69 * release a socket when done with it. 70 * 71 * soabort() destroys a socket without waiting for it to disconnect (used 72 * only for incoming connections that are already partially or fully 73 * connected). This is used internally by the socket layer when clearing 74 * listen socket queues (due to overflow or close on the listen socket), but 75 * is also a public interface protocols may use to abort connections in 76 * their incomplete listen queues should they no longer be required. Sockets 77 * placed in completed connection listen queues should not be aborted for 78 * reasons described in the comment above the soclose() implementation. This 79 * is not a general purpose close routine, and except in the specific 80 * circumstances described here, should not be used. 81 * 82 * sofree() will free a socket and its protocol state if all references on 83 * the socket have been released, and is the public interface to attempt to 84 * free a socket when a reference is removed. This is a socket layer private 85 * interface. 86 * 87 * NOTE: In addition to socreate() and soclose(), which provide a single 88 * socket reference to the consumer to be managed as required, there are two 89 * calls to explicitly manage socket references, soref(), and sorele(). 90 * Currently, these are generally required only when transitioning a socket 91 * from a listen queue to a file descriptor, in order to prevent garbage 92 * collection of the socket at an untimely moment. For a number of reasons, 93 * these interfaces are not preferred, and should be avoided. 94 */ 95 96 #include <sys/cdefs.h> 97 __FBSDID("$FreeBSD$"); 98 99 #include "opt_inet.h" 100 #include "opt_mac.h" 101 #include "opt_zero.h" 102 #include "opt_compat.h" 103 104 #include <sys/param.h> 105 #include <sys/systm.h> 106 #include <sys/fcntl.h> 107 #include <sys/limits.h> 108 #include <sys/lock.h> 109 #include <sys/mac.h> 110 #include <sys/malloc.h> 111 #include <sys/mbuf.h> 112 #include <sys/mutex.h> 113 #include <sys/domain.h> 114 #include <sys/file.h> /* for struct knote */ 115 #include <sys/kernel.h> 116 #include <sys/event.h> 117 #include <sys/eventhandler.h> 118 #include <sys/poll.h> 119 #include <sys/proc.h> 120 #include <sys/protosw.h> 121 #include <sys/socket.h> 122 #include <sys/socketvar.h> 123 #include <sys/resourcevar.h> 124 #include <sys/signalvar.h> 125 #include <sys/sysctl.h> 126 #include <sys/uio.h> 127 #include <sys/jail.h> 128 129 #include <vm/uma.h> 130 131 #ifdef COMPAT_IA32 132 #include <sys/mount.h> 133 #include <compat/freebsd32/freebsd32.h> 134 135 extern struct sysentvec ia32_freebsd_sysvec; 136 #endif 137 138 static int soreceive_rcvoob(struct socket *so, struct uio *uio, 139 int flags); 140 141 static void filt_sordetach(struct knote *kn); 142 static int filt_soread(struct knote *kn, long hint); 143 static void filt_sowdetach(struct knote *kn); 144 static int filt_sowrite(struct knote *kn, long hint); 145 static int filt_solisten(struct knote *kn, long hint); 146 147 static struct filterops solisten_filtops = 148 { 1, NULL, filt_sordetach, filt_solisten }; 149 static struct filterops soread_filtops = 150 { 1, NULL, filt_sordetach, filt_soread }; 151 static struct filterops sowrite_filtops = 152 { 1, NULL, filt_sowdetach, filt_sowrite }; 153 154 uma_zone_t socket_zone; 155 so_gen_t so_gencnt; /* generation count for sockets */ 156 157 int maxsockets; 158 159 MALLOC_DEFINE(M_SONAME, "soname", "socket name"); 160 MALLOC_DEFINE(M_PCB, "pcb", "protocol control block"); 161 162 static int somaxconn = SOMAXCONN; 163 static int somaxconn_sysctl(SYSCTL_HANDLER_ARGS); 164 /* XXX: we dont have SYSCTL_USHORT */ 165 SYSCTL_PROC(_kern_ipc, KIPC_SOMAXCONN, somaxconn, CTLTYPE_UINT | CTLFLAG_RW, 166 0, sizeof(int), somaxconn_sysctl, "I", "Maximum pending socket connection " 167 "queue size"); 168 static int numopensockets; 169 SYSCTL_INT(_kern_ipc, OID_AUTO, numopensockets, CTLFLAG_RD, 170 &numopensockets, 0, "Number of open sockets"); 171 #ifdef ZERO_COPY_SOCKETS 172 /* These aren't static because they're used in other files. */ 173 int so_zero_copy_send = 1; 174 int so_zero_copy_receive = 1; 175 SYSCTL_NODE(_kern_ipc, OID_AUTO, zero_copy, CTLFLAG_RD, 0, 176 "Zero copy controls"); 177 SYSCTL_INT(_kern_ipc_zero_copy, OID_AUTO, receive, CTLFLAG_RW, 178 &so_zero_copy_receive, 0, "Enable zero copy receive"); 179 SYSCTL_INT(_kern_ipc_zero_copy, OID_AUTO, send, CTLFLAG_RW, 180 &so_zero_copy_send, 0, "Enable zero copy send"); 181 #endif /* ZERO_COPY_SOCKETS */ 182 183 /* 184 * accept_mtx locks down per-socket fields relating to accept queues. See 185 * socketvar.h for an annotation of the protected fields of struct socket. 186 */ 187 struct mtx accept_mtx; 188 MTX_SYSINIT(accept_mtx, &accept_mtx, "accept", MTX_DEF); 189 190 /* 191 * so_global_mtx protects so_gencnt, numopensockets, and the per-socket 192 * so_gencnt field. 193 */ 194 static struct mtx so_global_mtx; 195 MTX_SYSINIT(so_global_mtx, &so_global_mtx, "so_glabel", MTX_DEF); 196 197 /* 198 * General IPC sysctl name space, used by sockets and a variety of other IPC 199 * types. 200 */ 201 SYSCTL_NODE(_kern, KERN_IPC, ipc, CTLFLAG_RW, 0, "IPC"); 202 203 /* 204 * Sysctl to get and set the maximum global sockets limit. Notify protocols 205 * of the change so that they can update their dependent limits as required. 206 */ 207 static int 208 sysctl_maxsockets(SYSCTL_HANDLER_ARGS) 209 { 210 int error, newmaxsockets; 211 212 newmaxsockets = maxsockets; 213 error = sysctl_handle_int(oidp, &newmaxsockets, sizeof(int), req); 214 if (error == 0 && req->newptr) { 215 if (newmaxsockets > maxsockets) { 216 maxsockets = newmaxsockets; 217 if (maxsockets > ((maxfiles / 4) * 3)) { 218 maxfiles = (maxsockets * 5) / 4; 219 maxfilesperproc = (maxfiles * 9) / 10; 220 } 221 EVENTHANDLER_INVOKE(maxsockets_change); 222 } else 223 error = EINVAL; 224 } 225 return (error); 226 } 227 228 SYSCTL_PROC(_kern_ipc, OID_AUTO, maxsockets, CTLTYPE_INT|CTLFLAG_RW, 229 &maxsockets, 0, sysctl_maxsockets, "IU", 230 "Maximum number of sockets avaliable"); 231 232 /* 233 * Initialise maxsockets. 234 */ 235 static void init_maxsockets(void *ignored) 236 { 237 TUNABLE_INT_FETCH("kern.ipc.maxsockets", &maxsockets); 238 maxsockets = imax(maxsockets, imax(maxfiles, nmbclusters)); 239 } 240 SYSINIT(param, SI_SUB_TUNABLES, SI_ORDER_ANY, init_maxsockets, NULL); 241 242 /* 243 * Socket operation routines. These routines are called by the routines in 244 * sys_socket.c or from a system process, and implement the semantics of 245 * socket operations by switching out to the protocol specific routines. 246 */ 247 248 /* 249 * Get a socket structure from our zone, and initialize it. Note that it 250 * would probably be better to allocate socket and PCB at the same time, but 251 * I'm not convinced that all the protocols can be easily modified to do 252 * this. 253 * 254 * soalloc() returns a socket with a ref count of 0. 255 */ 256 static struct socket * 257 soalloc(int mflags) 258 { 259 struct socket *so; 260 261 so = uma_zalloc(socket_zone, mflags | M_ZERO); 262 if (so == NULL) 263 return (NULL); 264 #ifdef MAC 265 if (mac_init_socket(so, mflags) != 0) { 266 uma_zfree(socket_zone, so); 267 return (NULL); 268 } 269 #endif 270 SOCKBUF_LOCK_INIT(&so->so_snd, "so_snd"); 271 SOCKBUF_LOCK_INIT(&so->so_rcv, "so_rcv"); 272 TAILQ_INIT(&so->so_aiojobq); 273 mtx_lock(&so_global_mtx); 274 so->so_gencnt = ++so_gencnt; 275 ++numopensockets; 276 mtx_unlock(&so_global_mtx); 277 return (so); 278 } 279 280 /* 281 * Free the storage associated with a socket at the socket layer, tear down 282 * locks, labels, etc. All protocol state is assumed already to have been 283 * torn down (and possibly never set up) by the caller. 284 */ 285 static void 286 sodealloc(struct socket *so) 287 { 288 289 KASSERT(so->so_count == 0, ("sodealloc(): so_count %d", so->so_count)); 290 KASSERT(so->so_pcb == NULL, ("sodealloc(): so_pcb != NULL")); 291 292 mtx_lock(&so_global_mtx); 293 so->so_gencnt = ++so_gencnt; 294 mtx_unlock(&so_global_mtx); 295 if (so->so_rcv.sb_hiwat) 296 (void)chgsbsize(so->so_cred->cr_uidinfo, 297 &so->so_rcv.sb_hiwat, 0, RLIM_INFINITY); 298 if (so->so_snd.sb_hiwat) 299 (void)chgsbsize(so->so_cred->cr_uidinfo, 300 &so->so_snd.sb_hiwat, 0, RLIM_INFINITY); 301 #ifdef INET 302 /* remove acccept filter if one is present. */ 303 if (so->so_accf != NULL) 304 do_setopt_accept_filter(so, NULL); 305 #endif 306 #ifdef MAC 307 mac_destroy_socket(so); 308 #endif 309 crfree(so->so_cred); 310 SOCKBUF_LOCK_DESTROY(&so->so_snd); 311 SOCKBUF_LOCK_DESTROY(&so->so_rcv); 312 uma_zfree(socket_zone, so); 313 mtx_lock(&so_global_mtx); 314 --numopensockets; 315 mtx_unlock(&so_global_mtx); 316 } 317 318 /* 319 * socreate returns a socket with a ref count of 1. The socket should be 320 * closed with soclose(). 321 */ 322 int 323 socreate(dom, aso, type, proto, cred, td) 324 int dom; 325 struct socket **aso; 326 int type; 327 int proto; 328 struct ucred *cred; 329 struct thread *td; 330 { 331 struct protosw *prp; 332 struct socket *so; 333 int error; 334 335 if (proto) 336 prp = pffindproto(dom, proto, type); 337 else 338 prp = pffindtype(dom, type); 339 340 if (prp == NULL || prp->pr_usrreqs->pru_attach == NULL || 341 prp->pr_usrreqs->pru_attach == pru_attach_notsupp) 342 return (EPROTONOSUPPORT); 343 344 if (jailed(cred) && jail_socket_unixiproute_only && 345 prp->pr_domain->dom_family != PF_LOCAL && 346 prp->pr_domain->dom_family != PF_INET && 347 prp->pr_domain->dom_family != PF_ROUTE) { 348 return (EPROTONOSUPPORT); 349 } 350 351 if (prp->pr_type != type) 352 return (EPROTOTYPE); 353 so = soalloc(M_WAITOK); 354 if (so == NULL) 355 return (ENOBUFS); 356 357 TAILQ_INIT(&so->so_incomp); 358 TAILQ_INIT(&so->so_comp); 359 so->so_type = type; 360 so->so_cred = crhold(cred); 361 so->so_proto = prp; 362 #ifdef MAC 363 mac_create_socket(cred, so); 364 #endif 365 knlist_init(&so->so_rcv.sb_sel.si_note, SOCKBUF_MTX(&so->so_rcv), 366 NULL, NULL, NULL); 367 knlist_init(&so->so_snd.sb_sel.si_note, SOCKBUF_MTX(&so->so_snd), 368 NULL, NULL, NULL); 369 so->so_count = 1; 370 error = (*prp->pr_usrreqs->pru_attach)(so, proto, td); 371 if (error) { 372 sodealloc(so); 373 return (error); 374 } 375 *aso = so; 376 return (0); 377 } 378 379 #ifdef REGRESSION 380 static int regression_sonewconn_earlytest = 1; 381 SYSCTL_INT(_regression, OID_AUTO, sonewconn_earlytest, CTLFLAG_RW, 382 ®ression_sonewconn_earlytest, 0, "Perform early sonewconn limit test"); 383 #endif 384 385 /* 386 * When an attempt at a new connection is noted on a socket which accepts 387 * connections, sonewconn is called. If the connection is possible (subject 388 * to space constraints, etc.) then we allocate a new structure, propoerly 389 * linked into the data structure of the original socket, and return this. 390 * Connstatus may be 0, or SO_ISCONFIRMING, or SO_ISCONNECTED. 391 * 392 * Note: the ref count on the socket is 0 on return. 393 */ 394 struct socket * 395 sonewconn(head, connstatus) 396 register struct socket *head; 397 int connstatus; 398 { 399 register struct socket *so; 400 int over; 401 402 ACCEPT_LOCK(); 403 over = (head->so_qlen > 3 * head->so_qlimit / 2); 404 ACCEPT_UNLOCK(); 405 #ifdef REGRESSION 406 if (regression_sonewconn_earlytest && over) 407 #else 408 if (over) 409 #endif 410 return (NULL); 411 so = soalloc(M_NOWAIT); 412 if (so == NULL) 413 return (NULL); 414 if ((head->so_options & SO_ACCEPTFILTER) != 0) 415 connstatus = 0; 416 so->so_head = head; 417 so->so_type = head->so_type; 418 so->so_options = head->so_options &~ SO_ACCEPTCONN; 419 so->so_linger = head->so_linger; 420 so->so_state = head->so_state | SS_NOFDREF; 421 so->so_proto = head->so_proto; 422 so->so_timeo = head->so_timeo; 423 so->so_cred = crhold(head->so_cred); 424 #ifdef MAC 425 SOCK_LOCK(head); 426 mac_create_socket_from_socket(head, so); 427 SOCK_UNLOCK(head); 428 #endif 429 knlist_init(&so->so_rcv.sb_sel.si_note, SOCKBUF_MTX(&so->so_rcv), 430 NULL, NULL, NULL); 431 knlist_init(&so->so_snd.sb_sel.si_note, SOCKBUF_MTX(&so->so_snd), 432 NULL, NULL, NULL); 433 if (soreserve(so, head->so_snd.sb_hiwat, head->so_rcv.sb_hiwat) || 434 (*so->so_proto->pr_usrreqs->pru_attach)(so, 0, NULL)) { 435 sodealloc(so); 436 return (NULL); 437 } 438 so->so_state |= connstatus; 439 ACCEPT_LOCK(); 440 if (connstatus) { 441 TAILQ_INSERT_TAIL(&head->so_comp, so, so_list); 442 so->so_qstate |= SQ_COMP; 443 head->so_qlen++; 444 } else { 445 /* 446 * Keep removing sockets from the head until there's room for 447 * us to insert on the tail. In pre-locking revisions, this 448 * was a simple if(), but as we could be racing with other 449 * threads and soabort() requires dropping locks, we must 450 * loop waiting for the condition to be true. 451 */ 452 while (head->so_incqlen > head->so_qlimit) { 453 struct socket *sp; 454 sp = TAILQ_FIRST(&head->so_incomp); 455 TAILQ_REMOVE(&head->so_incomp, sp, so_list); 456 head->so_incqlen--; 457 sp->so_qstate &= ~SQ_INCOMP; 458 sp->so_head = NULL; 459 ACCEPT_UNLOCK(); 460 soabort(sp); 461 ACCEPT_LOCK(); 462 } 463 TAILQ_INSERT_TAIL(&head->so_incomp, so, so_list); 464 so->so_qstate |= SQ_INCOMP; 465 head->so_incqlen++; 466 } 467 ACCEPT_UNLOCK(); 468 if (connstatus) { 469 sorwakeup(head); 470 wakeup_one(&head->so_timeo); 471 } 472 return (so); 473 } 474 475 int 476 sobind(so, nam, td) 477 struct socket *so; 478 struct sockaddr *nam; 479 struct thread *td; 480 { 481 482 return ((*so->so_proto->pr_usrreqs->pru_bind)(so, nam, td)); 483 } 484 485 /* 486 * solisten() transitions a socket from a non-listening state to a listening 487 * state, but can also be used to update the listen queue depth on an 488 * existing listen socket. The protocol will call back into the sockets 489 * layer using solisten_proto_check() and solisten_proto() to check and set 490 * socket-layer listen state. Call backs are used so that the protocol can 491 * acquire both protocol and socket layer locks in whatever order is required 492 * by the protocol. 493 * 494 * Protocol implementors are advised to hold the socket lock across the 495 * socket-layer test and set to avoid races at the socket layer. 496 */ 497 int 498 solisten(so, backlog, td) 499 struct socket *so; 500 int backlog; 501 struct thread *td; 502 { 503 504 return ((*so->so_proto->pr_usrreqs->pru_listen)(so, backlog, td)); 505 } 506 507 int 508 solisten_proto_check(so) 509 struct socket *so; 510 { 511 512 SOCK_LOCK_ASSERT(so); 513 514 if (so->so_state & (SS_ISCONNECTED | SS_ISCONNECTING | 515 SS_ISDISCONNECTING)) 516 return (EINVAL); 517 return (0); 518 } 519 520 void 521 solisten_proto(so, backlog) 522 struct socket *so; 523 int backlog; 524 { 525 526 SOCK_LOCK_ASSERT(so); 527 528 if (backlog < 0 || backlog > somaxconn) 529 backlog = somaxconn; 530 so->so_qlimit = backlog; 531 so->so_options |= SO_ACCEPTCONN; 532 } 533 534 /* 535 * Attempt to free a socket. This should really be sotryfree(). 536 * 537 * sofree() will succeed if: 538 * 539 * - There are no outstanding file descriptor references or related consumers 540 * (so_count == 0). 541 * 542 * - The socket has been closed by user space, if ever open (SS_NOFDREF). 543 * 544 * - The protocol does not have an outstanding strong reference on the socket 545 * (SS_PROTOREF). 546 * 547 * - The socket is not in a completed connection queue, so a process has been 548 * notified that it is present. If it is removed, the user process may 549 * block in accept() despite select() saying the socket was ready. 550 * 551 * Otherwise, it will quietly abort so that a future call to sofree(), when 552 * conditions are right, can succeed. 553 */ 554 void 555 sofree(so) 556 struct socket *so; 557 { 558 struct socket *head; 559 560 ACCEPT_LOCK_ASSERT(); 561 SOCK_LOCK_ASSERT(so); 562 563 if ((so->so_state & SS_NOFDREF) == 0 || so->so_count != 0 || 564 (so->so_state & SS_PROTOREF) || (so->so_qstate & SQ_COMP)) { 565 SOCK_UNLOCK(so); 566 ACCEPT_UNLOCK(); 567 return; 568 } 569 570 head = so->so_head; 571 if (head != NULL) { 572 KASSERT((so->so_qstate & SQ_COMP) != 0 || 573 (so->so_qstate & SQ_INCOMP) != 0, 574 ("sofree: so_head != NULL, but neither SQ_COMP nor " 575 "SQ_INCOMP")); 576 KASSERT((so->so_qstate & SQ_COMP) == 0 || 577 (so->so_qstate & SQ_INCOMP) == 0, 578 ("sofree: so->so_qstate is SQ_COMP and also SQ_INCOMP")); 579 TAILQ_REMOVE(&head->so_incomp, so, so_list); 580 head->so_incqlen--; 581 so->so_qstate &= ~SQ_INCOMP; 582 so->so_head = NULL; 583 } 584 KASSERT((so->so_qstate & SQ_COMP) == 0 && 585 (so->so_qstate & SQ_INCOMP) == 0, 586 ("sofree: so_head == NULL, but still SQ_COMP(%d) or SQ_INCOMP(%d)", 587 so->so_qstate & SQ_COMP, so->so_qstate & SQ_INCOMP)); 588 SOCK_UNLOCK(so); 589 ACCEPT_UNLOCK(); 590 591 SOCKBUF_LOCK(&so->so_snd); 592 so->so_snd.sb_flags |= SB_NOINTR; 593 (void)sblock(&so->so_snd, M_WAITOK); 594 /* 595 * socantsendmore_locked() drops the socket buffer mutex so that it 596 * can safely perform wakeups. Re-acquire the mutex before 597 * continuing. 598 */ 599 socantsendmore_locked(so); 600 SOCKBUF_LOCK(&so->so_snd); 601 sbunlock(&so->so_snd); 602 sbrelease_locked(&so->so_snd, so); 603 SOCKBUF_UNLOCK(&so->so_snd); 604 sorflush(so); 605 knlist_destroy(&so->so_rcv.sb_sel.si_note); 606 knlist_destroy(&so->so_snd.sb_sel.si_note); 607 if (so->so_proto->pr_usrreqs->pru_detach != NULL) 608 (*so->so_proto->pr_usrreqs->pru_detach)(so); 609 sodealloc(so); 610 } 611 612 /* 613 * Close a socket on last file table reference removal. Initiate disconnect 614 * if connected. Free socket when disconnect complete. 615 * 616 * This function will sorele() the socket. Note that soclose() may be called 617 * prior to the ref count reaching zero. The actual socket structure will 618 * not be freed until the ref count reaches zero. 619 */ 620 int 621 soclose(so) 622 struct socket *so; 623 { 624 int error = 0; 625 626 KASSERT(!(so->so_state & SS_NOFDREF), ("soclose: SS_NOFDREF on enter")); 627 628 funsetown(&so->so_sigio); 629 if (so->so_options & SO_ACCEPTCONN) { 630 struct socket *sp; 631 ACCEPT_LOCK(); 632 while ((sp = TAILQ_FIRST(&so->so_incomp)) != NULL) { 633 TAILQ_REMOVE(&so->so_incomp, sp, so_list); 634 so->so_incqlen--; 635 sp->so_qstate &= ~SQ_INCOMP; 636 sp->so_head = NULL; 637 ACCEPT_UNLOCK(); 638 soabort(sp); 639 ACCEPT_LOCK(); 640 } 641 while ((sp = TAILQ_FIRST(&so->so_comp)) != NULL) { 642 TAILQ_REMOVE(&so->so_comp, sp, so_list); 643 so->so_qlen--; 644 sp->so_qstate &= ~SQ_COMP; 645 sp->so_head = NULL; 646 ACCEPT_UNLOCK(); 647 soabort(sp); 648 ACCEPT_LOCK(); 649 } 650 ACCEPT_UNLOCK(); 651 } 652 if (so->so_state & SS_ISCONNECTED) { 653 if ((so->so_state & SS_ISDISCONNECTING) == 0) { 654 error = sodisconnect(so); 655 if (error) 656 goto drop; 657 } 658 if (so->so_options & SO_LINGER) { 659 if ((so->so_state & SS_ISDISCONNECTING) && 660 (so->so_state & SS_NBIO)) 661 goto drop; 662 while (so->so_state & SS_ISCONNECTED) { 663 error = tsleep(&so->so_timeo, 664 PSOCK | PCATCH, "soclos", so->so_linger * hz); 665 if (error) 666 break; 667 } 668 } 669 } 670 671 drop: 672 if (so->so_proto->pr_usrreqs->pru_close != NULL) 673 (*so->so_proto->pr_usrreqs->pru_close)(so); 674 ACCEPT_LOCK(); 675 SOCK_LOCK(so); 676 KASSERT((so->so_state & SS_NOFDREF) == 0, ("soclose: NOFDREF")); 677 so->so_state |= SS_NOFDREF; 678 sorele(so); 679 return (error); 680 } 681 682 /* 683 * soabort() is used to abruptly tear down a connection, such as when a 684 * resource limit is reached (listen queue depth exceeded), or if a listen 685 * socket is closed while there are sockets waiting to be accepted. 686 * 687 * This interface is tricky, because it is called on an unreferenced socket, 688 * and must be called only by a thread that has actually removed the socket 689 * from the listen queue it was on, or races with other threads are risked. 690 * 691 * This interface will call into the protocol code, so must not be called 692 * with any socket locks held. Protocols do call it while holding their own 693 * recursible protocol mutexes, but this is something that should be subject 694 * to review in the future. 695 */ 696 void 697 soabort(so) 698 struct socket *so; 699 { 700 701 /* 702 * In as much as is possible, assert that no references to this 703 * socket are held. This is not quite the same as asserting that the 704 * current thread is responsible for arranging for no references, but 705 * is as close as we can get for now. 706 */ 707 KASSERT(so->so_count == 0, ("soabort: so_count")); 708 KASSERT((so->so_state & SS_PROTOREF) == 0, ("soabort: SS_PROTOREF")); 709 KASSERT(so->so_state & SS_NOFDREF, ("soabort: !SS_NOFDREF")); 710 KASSERT((so->so_state & SQ_COMP) == 0, ("soabort: SQ_COMP")); 711 KASSERT((so->so_state & SQ_INCOMP) == 0, ("soabort: SQ_INCOMP")); 712 713 if (so->so_proto->pr_usrreqs->pru_abort != NULL) 714 (*so->so_proto->pr_usrreqs->pru_abort)(so); 715 ACCEPT_LOCK(); 716 SOCK_LOCK(so); 717 sofree(so); 718 } 719 720 int 721 soaccept(so, nam) 722 struct socket *so; 723 struct sockaddr **nam; 724 { 725 int error; 726 727 SOCK_LOCK(so); 728 KASSERT((so->so_state & SS_NOFDREF) != 0, ("soaccept: !NOFDREF")); 729 so->so_state &= ~SS_NOFDREF; 730 SOCK_UNLOCK(so); 731 error = (*so->so_proto->pr_usrreqs->pru_accept)(so, nam); 732 return (error); 733 } 734 735 int 736 soconnect(so, nam, td) 737 struct socket *so; 738 struct sockaddr *nam; 739 struct thread *td; 740 { 741 int error; 742 743 if (so->so_options & SO_ACCEPTCONN) 744 return (EOPNOTSUPP); 745 /* 746 * If protocol is connection-based, can only connect once. 747 * Otherwise, if connected, try to disconnect first. This allows 748 * user to disconnect by connecting to, e.g., a null address. 749 */ 750 if (so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING) && 751 ((so->so_proto->pr_flags & PR_CONNREQUIRED) || 752 (error = sodisconnect(so)))) { 753 error = EISCONN; 754 } else { 755 /* 756 * Prevent accumulated error from previous connection from 757 * biting us. 758 */ 759 so->so_error = 0; 760 error = (*so->so_proto->pr_usrreqs->pru_connect)(so, nam, td); 761 } 762 763 return (error); 764 } 765 766 int 767 soconnect2(so1, so2) 768 struct socket *so1; 769 struct socket *so2; 770 { 771 772 return ((*so1->so_proto->pr_usrreqs->pru_connect2)(so1, so2)); 773 } 774 775 int 776 sodisconnect(so) 777 struct socket *so; 778 { 779 int error; 780 781 if ((so->so_state & SS_ISCONNECTED) == 0) 782 return (ENOTCONN); 783 if (so->so_state & SS_ISDISCONNECTING) 784 return (EALREADY); 785 error = (*so->so_proto->pr_usrreqs->pru_disconnect)(so); 786 return (error); 787 } 788 789 #ifdef ZERO_COPY_SOCKETS 790 struct so_zerocopy_stats{ 791 int size_ok; 792 int align_ok; 793 int found_ifp; 794 }; 795 struct so_zerocopy_stats so_zerocp_stats = {0,0,0}; 796 #include <netinet/in.h> 797 #include <net/route.h> 798 #include <netinet/in_pcb.h> 799 #include <vm/vm.h> 800 #include <vm/vm_page.h> 801 #include <vm/vm_object.h> 802 #endif /*ZERO_COPY_SOCKETS*/ 803 804 /* 805 * sosend_copyin() accepts a uio and prepares an mbuf chain holding part or 806 * all of the data referenced by the uio. If desired, it uses zero-copy. 807 * *space will be updated to reflect data copied in. 808 * 809 * NB: If atomic I/O is requested, the caller must already have checked that 810 * space can hold resid bytes. 811 * 812 * NB: In the event of an error, the caller may need to free the partial 813 * chain pointed to by *mpp. The contents of both *uio and *space may be 814 * modified even in the case of an error. 815 */ 816 static int 817 sosend_copyin(struct uio *uio, struct mbuf **retmp, int atomic, long *space, 818 int flags) 819 { 820 struct mbuf *m, **mp, *top; 821 long len, resid; 822 int error; 823 #ifdef ZERO_COPY_SOCKETS 824 int cow_send; 825 #endif 826 827 *retmp = top = NULL; 828 mp = ⊤ 829 len = 0; 830 resid = uio->uio_resid; 831 error = 0; 832 do { 833 #ifdef ZERO_COPY_SOCKETS 834 cow_send = 0; 835 #endif /* ZERO_COPY_SOCKETS */ 836 if (resid >= MINCLSIZE) { 837 #ifdef ZERO_COPY_SOCKETS 838 if (top == NULL) { 839 MGETHDR(m, M_TRYWAIT, MT_DATA); 840 if (m == NULL) { 841 error = ENOBUFS; 842 goto out; 843 } 844 m->m_pkthdr.len = 0; 845 m->m_pkthdr.rcvif = NULL; 846 } else { 847 MGET(m, M_TRYWAIT, MT_DATA); 848 if (m == NULL) { 849 error = ENOBUFS; 850 goto out; 851 } 852 } 853 if (so_zero_copy_send && 854 resid>=PAGE_SIZE && 855 *space>=PAGE_SIZE && 856 uio->uio_iov->iov_len>=PAGE_SIZE) { 857 so_zerocp_stats.size_ok++; 858 so_zerocp_stats.align_ok++; 859 cow_send = socow_setup(m, uio); 860 len = cow_send; 861 } 862 if (!cow_send) { 863 MCLGET(m, M_TRYWAIT); 864 if ((m->m_flags & M_EXT) == 0) { 865 m_free(m); 866 m = NULL; 867 } else { 868 len = min(min(MCLBYTES, resid), 869 *space); 870 } 871 } 872 #else /* ZERO_COPY_SOCKETS */ 873 if (top == NULL) { 874 m = m_getcl(M_TRYWAIT, MT_DATA, M_PKTHDR); 875 m->m_pkthdr.len = 0; 876 m->m_pkthdr.rcvif = NULL; 877 } else 878 m = m_getcl(M_TRYWAIT, MT_DATA, 0); 879 len = min(min(MCLBYTES, resid), *space); 880 #endif /* ZERO_COPY_SOCKETS */ 881 } else { 882 if (top == NULL) { 883 m = m_gethdr(M_TRYWAIT, MT_DATA); 884 m->m_pkthdr.len = 0; 885 m->m_pkthdr.rcvif = NULL; 886 887 len = min(min(MHLEN, resid), *space); 888 /* 889 * For datagram protocols, leave room 890 * for protocol headers in first mbuf. 891 */ 892 if (atomic && m && len < MHLEN) 893 MH_ALIGN(m, len); 894 } else { 895 m = m_get(M_TRYWAIT, MT_DATA); 896 len = min(min(MLEN, resid), *space); 897 } 898 } 899 if (m == NULL) { 900 error = ENOBUFS; 901 goto out; 902 } 903 904 *space -= len; 905 #ifdef ZERO_COPY_SOCKETS 906 if (cow_send) 907 error = 0; 908 else 909 #endif /* ZERO_COPY_SOCKETS */ 910 error = uiomove(mtod(m, void *), (int)len, uio); 911 resid = uio->uio_resid; 912 m->m_len = len; 913 *mp = m; 914 top->m_pkthdr.len += len; 915 if (error) 916 goto out; 917 mp = &m->m_next; 918 if (resid <= 0) { 919 if (flags & MSG_EOR) 920 top->m_flags |= M_EOR; 921 break; 922 } 923 } while (*space > 0 && atomic); 924 out: 925 *retmp = top; 926 return (error); 927 } 928 929 #define SBLOCKWAIT(f) (((f) & MSG_DONTWAIT) ? M_NOWAIT : M_WAITOK) 930 931 int 932 sosend_dgram(so, addr, uio, top, control, flags, td) 933 struct socket *so; 934 struct sockaddr *addr; 935 struct uio *uio; 936 struct mbuf *top; 937 struct mbuf *control; 938 int flags; 939 struct thread *td; 940 { 941 long space, resid; 942 int clen = 0, error, dontroute; 943 int atomic = sosendallatonce(so) || top; 944 945 KASSERT(so->so_type == SOCK_DGRAM, ("sodgram_send: !SOCK_DGRAM")); 946 KASSERT(so->so_proto->pr_flags & PR_ATOMIC, 947 ("sodgram_send: !PR_ATOMIC")); 948 949 if (uio != NULL) 950 resid = uio->uio_resid; 951 else 952 resid = top->m_pkthdr.len; 953 /* 954 * In theory resid should be unsigned. However, space must be 955 * signed, as it might be less than 0 if we over-committed, and we 956 * must use a signed comparison of space and resid. On the other 957 * hand, a negative resid causes us to loop sending 0-length 958 * segments to the protocol. 959 * 960 * Also check to make sure that MSG_EOR isn't used on SOCK_STREAM 961 * type sockets since that's an error. 962 */ 963 if (resid < 0) { 964 error = EINVAL; 965 goto out; 966 } 967 968 dontroute = 969 (flags & MSG_DONTROUTE) && (so->so_options & SO_DONTROUTE) == 0; 970 if (td != NULL) 971 td->td_proc->p_stats->p_ru.ru_msgsnd++; 972 if (control != NULL) 973 clen = control->m_len; 974 975 SOCKBUF_LOCK(&so->so_snd); 976 if (so->so_snd.sb_state & SBS_CANTSENDMORE) { 977 SOCKBUF_UNLOCK(&so->so_snd); 978 error = EPIPE; 979 goto out; 980 } 981 if (so->so_error) { 982 error = so->so_error; 983 so->so_error = 0; 984 SOCKBUF_UNLOCK(&so->so_snd); 985 goto out; 986 } 987 if ((so->so_state & SS_ISCONNECTED) == 0) { 988 /* 989 * `sendto' and `sendmsg' is allowed on a connection-based 990 * socket if it supports implied connect. Return ENOTCONN if 991 * not connected and no address is supplied. 992 */ 993 if ((so->so_proto->pr_flags & PR_CONNREQUIRED) && 994 (so->so_proto->pr_flags & PR_IMPLOPCL) == 0) { 995 if ((so->so_state & SS_ISCONFIRMING) == 0 && 996 !(resid == 0 && clen != 0)) { 997 SOCKBUF_UNLOCK(&so->so_snd); 998 error = ENOTCONN; 999 goto out; 1000 } 1001 } else if (addr == NULL) { 1002 if (so->so_proto->pr_flags & PR_CONNREQUIRED) 1003 error = ENOTCONN; 1004 else 1005 error = EDESTADDRREQ; 1006 SOCKBUF_UNLOCK(&so->so_snd); 1007 goto out; 1008 } 1009 } 1010 1011 /* 1012 * Do we need MSG_OOB support in SOCK_DGRAM? Signs here may be a 1013 * problem and need fixing. 1014 */ 1015 space = sbspace(&so->so_snd); 1016 if (flags & MSG_OOB) 1017 space += 1024; 1018 space -= clen; 1019 if (resid > space) { 1020 error = EMSGSIZE; 1021 goto out; 1022 } 1023 SOCKBUF_UNLOCK(&so->so_snd); 1024 if (uio == NULL) { 1025 resid = 0; 1026 if (flags & MSG_EOR) 1027 top->m_flags |= M_EOR; 1028 } else { 1029 error = sosend_copyin(uio, &top, atomic, &space, flags); 1030 if (error) 1031 goto out; 1032 resid = uio->uio_resid; 1033 } 1034 KASSERT(resid == 0, ("sosend_dgram: resid != 0")); 1035 /* 1036 * XXXRW: Frobbing SO_DONTROUTE here is even worse without sblock 1037 * than with. 1038 */ 1039 if (dontroute) { 1040 SOCK_LOCK(so); 1041 so->so_options |= SO_DONTROUTE; 1042 SOCK_UNLOCK(so); 1043 } 1044 /* 1045 * XXX all the SBS_CANTSENDMORE checks previously done could be out 1046 * of date. We could have recieved a reset packet in an interrupt or 1047 * maybe we slept while doing page faults in uiomove() etc. We could 1048 * probably recheck again inside the locking protection here, but 1049 * there are probably other places that this also happens. We must 1050 * rethink this. 1051 */ 1052 error = (*so->so_proto->pr_usrreqs->pru_send)(so, 1053 (flags & MSG_OOB) ? PRUS_OOB : 1054 /* 1055 * If the user set MSG_EOF, the protocol understands this flag and 1056 * nothing left to send then use PRU_SEND_EOF instead of PRU_SEND. 1057 */ 1058 ((flags & MSG_EOF) && 1059 (so->so_proto->pr_flags & PR_IMPLOPCL) && 1060 (resid <= 0)) ? 1061 PRUS_EOF : 1062 /* If there is more to send set PRUS_MORETOCOME */ 1063 (resid > 0 && space > 0) ? PRUS_MORETOCOME : 0, 1064 top, addr, control, td); 1065 if (dontroute) { 1066 SOCK_LOCK(so); 1067 so->so_options &= ~SO_DONTROUTE; 1068 SOCK_UNLOCK(so); 1069 } 1070 clen = 0; 1071 control = NULL; 1072 top = NULL; 1073 out: 1074 if (top != NULL) 1075 m_freem(top); 1076 if (control != NULL) 1077 m_freem(control); 1078 return (error); 1079 } 1080 1081 /* 1082 * Send on a socket. If send must go all at once and message is larger than 1083 * send buffering, then hard error. Lock against other senders. If must go 1084 * all at once and not enough room now, then inform user that this would 1085 * block and do nothing. Otherwise, if nonblocking, send as much as 1086 * possible. The data to be sent is described by "uio" if nonzero, otherwise 1087 * by the mbuf chain "top" (which must be null if uio is not). Data provided 1088 * in mbuf chain must be small enough to send all at once. 1089 * 1090 * Returns nonzero on error, timeout or signal; callers must check for short 1091 * counts if EINTR/ERESTART are returned. Data and control buffers are freed 1092 * on return. 1093 */ 1094 #define snderr(errno) { error = (errno); goto release; } 1095 int 1096 sosend_generic(so, addr, uio, top, control, flags, td) 1097 struct socket *so; 1098 struct sockaddr *addr; 1099 struct uio *uio; 1100 struct mbuf *top; 1101 struct mbuf *control; 1102 int flags; 1103 struct thread *td; 1104 { 1105 long space, resid; 1106 int clen = 0, error, dontroute; 1107 int atomic = sosendallatonce(so) || top; 1108 1109 if (uio != NULL) 1110 resid = uio->uio_resid; 1111 else 1112 resid = top->m_pkthdr.len; 1113 /* 1114 * In theory resid should be unsigned. However, space must be 1115 * signed, as it might be less than 0 if we over-committed, and we 1116 * must use a signed comparison of space and resid. On the other 1117 * hand, a negative resid causes us to loop sending 0-length 1118 * segments to the protocol. 1119 * 1120 * Also check to make sure that MSG_EOR isn't used on SOCK_STREAM 1121 * type sockets since that's an error. 1122 */ 1123 if (resid < 0 || (so->so_type == SOCK_STREAM && (flags & MSG_EOR))) { 1124 error = EINVAL; 1125 goto out; 1126 } 1127 1128 dontroute = 1129 (flags & MSG_DONTROUTE) && (so->so_options & SO_DONTROUTE) == 0 && 1130 (so->so_proto->pr_flags & PR_ATOMIC); 1131 if (td != NULL) 1132 td->td_proc->p_stats->p_ru.ru_msgsnd++; 1133 if (control != NULL) 1134 clen = control->m_len; 1135 1136 SOCKBUF_LOCK(&so->so_snd); 1137 restart: 1138 SOCKBUF_LOCK_ASSERT(&so->so_snd); 1139 error = sblock(&so->so_snd, SBLOCKWAIT(flags)); 1140 if (error) 1141 goto out_locked; 1142 do { 1143 SOCKBUF_LOCK_ASSERT(&so->so_snd); 1144 if (so->so_snd.sb_state & SBS_CANTSENDMORE) 1145 snderr(EPIPE); 1146 if (so->so_error) { 1147 error = so->so_error; 1148 so->so_error = 0; 1149 goto release; 1150 } 1151 if ((so->so_state & SS_ISCONNECTED) == 0) { 1152 /* 1153 * `sendto' and `sendmsg' is allowed on a connection- 1154 * based socket if it supports implied connect. 1155 * Return ENOTCONN if not connected and no address is 1156 * supplied. 1157 */ 1158 if ((so->so_proto->pr_flags & PR_CONNREQUIRED) && 1159 (so->so_proto->pr_flags & PR_IMPLOPCL) == 0) { 1160 if ((so->so_state & SS_ISCONFIRMING) == 0 && 1161 !(resid == 0 && clen != 0)) 1162 snderr(ENOTCONN); 1163 } else if (addr == NULL) 1164 snderr(so->so_proto->pr_flags & PR_CONNREQUIRED ? 1165 ENOTCONN : EDESTADDRREQ); 1166 } 1167 space = sbspace(&so->so_snd); 1168 if (flags & MSG_OOB) 1169 space += 1024; 1170 if ((atomic && resid > so->so_snd.sb_hiwat) || 1171 clen > so->so_snd.sb_hiwat) 1172 snderr(EMSGSIZE); 1173 if (space < resid + clen && 1174 (atomic || space < so->so_snd.sb_lowat || space < clen)) { 1175 if ((so->so_state & SS_NBIO) || (flags & MSG_NBIO)) 1176 snderr(EWOULDBLOCK); 1177 sbunlock(&so->so_snd); 1178 error = sbwait(&so->so_snd); 1179 if (error) 1180 goto out_locked; 1181 goto restart; 1182 } 1183 SOCKBUF_UNLOCK(&so->so_snd); 1184 space -= clen; 1185 do { 1186 if (uio == NULL) { 1187 resid = 0; 1188 if (flags & MSG_EOR) 1189 top->m_flags |= M_EOR; 1190 } else { 1191 error = sosend_copyin(uio, &top, atomic, 1192 &space, flags); 1193 if (error != 0) { 1194 SOCKBUF_LOCK(&so->so_snd); 1195 goto release; 1196 } 1197 resid = uio->uio_resid; 1198 } 1199 if (dontroute) { 1200 SOCK_LOCK(so); 1201 so->so_options |= SO_DONTROUTE; 1202 SOCK_UNLOCK(so); 1203 } 1204 /* 1205 * XXX all the SBS_CANTSENDMORE checks previously 1206 * done could be out of date. We could have recieved 1207 * a reset packet in an interrupt or maybe we slept 1208 * while doing page faults in uiomove() etc. We 1209 * could probably recheck again inside the locking 1210 * protection here, but there are probably other 1211 * places that this also happens. We must rethink 1212 * this. 1213 */ 1214 error = (*so->so_proto->pr_usrreqs->pru_send)(so, 1215 (flags & MSG_OOB) ? PRUS_OOB : 1216 /* 1217 * If the user set MSG_EOF, the protocol understands 1218 * this flag and nothing left to send then use 1219 * PRU_SEND_EOF instead of PRU_SEND. 1220 */ 1221 ((flags & MSG_EOF) && 1222 (so->so_proto->pr_flags & PR_IMPLOPCL) && 1223 (resid <= 0)) ? 1224 PRUS_EOF : 1225 /* If there is more to send set PRUS_MORETOCOME. */ 1226 (resid > 0 && space > 0) ? PRUS_MORETOCOME : 0, 1227 top, addr, control, td); 1228 if (dontroute) { 1229 SOCK_LOCK(so); 1230 so->so_options &= ~SO_DONTROUTE; 1231 SOCK_UNLOCK(so); 1232 } 1233 clen = 0; 1234 control = NULL; 1235 top = NULL; 1236 if (error) { 1237 SOCKBUF_LOCK(&so->so_snd); 1238 goto release; 1239 } 1240 } while (resid && space > 0); 1241 SOCKBUF_LOCK(&so->so_snd); 1242 } while (resid); 1243 1244 release: 1245 SOCKBUF_LOCK_ASSERT(&so->so_snd); 1246 sbunlock(&so->so_snd); 1247 out_locked: 1248 SOCKBUF_LOCK_ASSERT(&so->so_snd); 1249 SOCKBUF_UNLOCK(&so->so_snd); 1250 out: 1251 if (top != NULL) 1252 m_freem(top); 1253 if (control != NULL) 1254 m_freem(control); 1255 return (error); 1256 } 1257 #undef snderr 1258 1259 int 1260 sosend(so, addr, uio, top, control, flags, td) 1261 struct socket *so; 1262 struct sockaddr *addr; 1263 struct uio *uio; 1264 struct mbuf *top; 1265 struct mbuf *control; 1266 int flags; 1267 struct thread *td; 1268 { 1269 1270 /* XXXRW: Temporary debugging. */ 1271 KASSERT(so->so_proto->pr_usrreqs->pru_sosend != sosend, 1272 ("sosend: protocol calls sosend")); 1273 1274 return (so->so_proto->pr_usrreqs->pru_sosend(so, addr, uio, top, 1275 control, flags, td)); 1276 } 1277 1278 /* 1279 * The part of soreceive() that implements reading non-inline out-of-band 1280 * data from a socket. For more complete comments, see soreceive(), from 1281 * which this code originated. 1282 * 1283 * Note that soreceive_rcvoob(), unlike the remainder of soreceive(), is 1284 * unable to return an mbuf chain to the caller. 1285 */ 1286 static int 1287 soreceive_rcvoob(so, uio, flags) 1288 struct socket *so; 1289 struct uio *uio; 1290 int flags; 1291 { 1292 struct protosw *pr = so->so_proto; 1293 struct mbuf *m; 1294 int error; 1295 1296 KASSERT(flags & MSG_OOB, ("soreceive_rcvoob: (flags & MSG_OOB) == 0")); 1297 1298 m = m_get(M_TRYWAIT, MT_DATA); 1299 if (m == NULL) 1300 return (ENOBUFS); 1301 error = (*pr->pr_usrreqs->pru_rcvoob)(so, m, flags & MSG_PEEK); 1302 if (error) 1303 goto bad; 1304 do { 1305 #ifdef ZERO_COPY_SOCKETS 1306 if (so_zero_copy_receive) { 1307 int disposable; 1308 1309 if ((m->m_flags & M_EXT) 1310 && (m->m_ext.ext_type == EXT_DISPOSABLE)) 1311 disposable = 1; 1312 else 1313 disposable = 0; 1314 1315 error = uiomoveco(mtod(m, void *), 1316 min(uio->uio_resid, m->m_len), 1317 uio, disposable); 1318 } else 1319 #endif /* ZERO_COPY_SOCKETS */ 1320 error = uiomove(mtod(m, void *), 1321 (int) min(uio->uio_resid, m->m_len), uio); 1322 m = m_free(m); 1323 } while (uio->uio_resid && error == 0 && m); 1324 bad: 1325 if (m != NULL) 1326 m_freem(m); 1327 return (error); 1328 } 1329 1330 /* 1331 * Following replacement or removal of the first mbuf on the first mbuf chain 1332 * of a socket buffer, push necessary state changes back into the socket 1333 * buffer so that other consumers see the values consistently. 'nextrecord' 1334 * is the callers locally stored value of the original value of 1335 * sb->sb_mb->m_nextpkt which must be restored when the lead mbuf changes. 1336 * NOTE: 'nextrecord' may be NULL. 1337 */ 1338 static __inline void 1339 sockbuf_pushsync(struct sockbuf *sb, struct mbuf *nextrecord) 1340 { 1341 1342 SOCKBUF_LOCK_ASSERT(sb); 1343 /* 1344 * First, update for the new value of nextrecord. If necessary, make 1345 * it the first record. 1346 */ 1347 if (sb->sb_mb != NULL) 1348 sb->sb_mb->m_nextpkt = nextrecord; 1349 else 1350 sb->sb_mb = nextrecord; 1351 1352 /* 1353 * Now update any dependent socket buffer fields to reflect the new 1354 * state. This is an expanded inline of SB_EMPTY_FIXUP(), with the 1355 * addition of a second clause that takes care of the case where 1356 * sb_mb has been updated, but remains the last record. 1357 */ 1358 if (sb->sb_mb == NULL) { 1359 sb->sb_mbtail = NULL; 1360 sb->sb_lastrecord = NULL; 1361 } else if (sb->sb_mb->m_nextpkt == NULL) 1362 sb->sb_lastrecord = sb->sb_mb; 1363 } 1364 1365 1366 /* 1367 * Implement receive operations on a socket. We depend on the way that 1368 * records are added to the sockbuf by sbappend. In particular, each record 1369 * (mbufs linked through m_next) must begin with an address if the protocol 1370 * so specifies, followed by an optional mbuf or mbufs containing ancillary 1371 * data, and then zero or more mbufs of data. In order to allow parallelism 1372 * between network receive and copying to user space, as well as avoid 1373 * sleeping with a mutex held, we release the socket buffer mutex during the 1374 * user space copy. Although the sockbuf is locked, new data may still be 1375 * appended, and thus we must maintain consistency of the sockbuf during that 1376 * time. 1377 * 1378 * The caller may receive the data as a single mbuf chain by supplying an 1379 * mbuf **mp0 for use in returning the chain. The uio is then used only for 1380 * the count in uio_resid. 1381 */ 1382 int 1383 soreceive_generic(so, psa, uio, mp0, controlp, flagsp) 1384 struct socket *so; 1385 struct sockaddr **psa; 1386 struct uio *uio; 1387 struct mbuf **mp0; 1388 struct mbuf **controlp; 1389 int *flagsp; 1390 { 1391 struct mbuf *m, **mp; 1392 int flags, len, error, offset; 1393 struct protosw *pr = so->so_proto; 1394 struct mbuf *nextrecord; 1395 int moff, type = 0; 1396 int orig_resid = uio->uio_resid; 1397 1398 mp = mp0; 1399 if (psa != NULL) 1400 *psa = NULL; 1401 if (controlp != NULL) 1402 *controlp = NULL; 1403 if (flagsp != NULL) 1404 flags = *flagsp &~ MSG_EOR; 1405 else 1406 flags = 0; 1407 if (flags & MSG_OOB) 1408 return (soreceive_rcvoob(so, uio, flags)); 1409 if (mp != NULL) 1410 *mp = NULL; 1411 if ((pr->pr_flags & PR_WANTRCVD) && (so->so_state & SS_ISCONFIRMING) 1412 && uio->uio_resid) 1413 (*pr->pr_usrreqs->pru_rcvd)(so, 0); 1414 1415 SOCKBUF_LOCK(&so->so_rcv); 1416 restart: 1417 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 1418 error = sblock(&so->so_rcv, SBLOCKWAIT(flags)); 1419 if (error) 1420 goto out; 1421 1422 m = so->so_rcv.sb_mb; 1423 /* 1424 * If we have less data than requested, block awaiting more (subject 1425 * to any timeout) if: 1426 * 1. the current count is less than the low water mark, or 1427 * 2. MSG_WAITALL is set, and it is possible to do the entire 1428 * receive operation at once if we block (resid <= hiwat). 1429 * 3. MSG_DONTWAIT is not set 1430 * If MSG_WAITALL is set but resid is larger than the receive buffer, 1431 * we have to do the receive in sections, and thus risk returning a 1432 * short count if a timeout or signal occurs after we start. 1433 */ 1434 if (m == NULL || (((flags & MSG_DONTWAIT) == 0 && 1435 so->so_rcv.sb_cc < uio->uio_resid) && 1436 (so->so_rcv.sb_cc < so->so_rcv.sb_lowat || 1437 ((flags & MSG_WAITALL) && uio->uio_resid <= so->so_rcv.sb_hiwat)) && 1438 m->m_nextpkt == NULL && (pr->pr_flags & PR_ATOMIC) == 0)) { 1439 KASSERT(m != NULL || !so->so_rcv.sb_cc, 1440 ("receive: m == %p so->so_rcv.sb_cc == %u", 1441 m, so->so_rcv.sb_cc)); 1442 if (so->so_error) { 1443 if (m != NULL) 1444 goto dontblock; 1445 error = so->so_error; 1446 if ((flags & MSG_PEEK) == 0) 1447 so->so_error = 0; 1448 goto release; 1449 } 1450 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 1451 if (so->so_rcv.sb_state & SBS_CANTRCVMORE) { 1452 if (m) 1453 goto dontblock; 1454 else 1455 goto release; 1456 } 1457 for (; m != NULL; m = m->m_next) 1458 if (m->m_type == MT_OOBDATA || (m->m_flags & M_EOR)) { 1459 m = so->so_rcv.sb_mb; 1460 goto dontblock; 1461 } 1462 if ((so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING)) == 0 && 1463 (so->so_proto->pr_flags & PR_CONNREQUIRED)) { 1464 error = ENOTCONN; 1465 goto release; 1466 } 1467 if (uio->uio_resid == 0) 1468 goto release; 1469 if ((so->so_state & SS_NBIO) || 1470 (flags & (MSG_DONTWAIT|MSG_NBIO))) { 1471 error = EWOULDBLOCK; 1472 goto release; 1473 } 1474 SBLASTRECORDCHK(&so->so_rcv); 1475 SBLASTMBUFCHK(&so->so_rcv); 1476 sbunlock(&so->so_rcv); 1477 error = sbwait(&so->so_rcv); 1478 if (error) 1479 goto out; 1480 goto restart; 1481 } 1482 dontblock: 1483 /* 1484 * From this point onward, we maintain 'nextrecord' as a cache of the 1485 * pointer to the next record in the socket buffer. We must keep the 1486 * various socket buffer pointers and local stack versions of the 1487 * pointers in sync, pushing out modifications before dropping the 1488 * socket buffer mutex, and re-reading them when picking it up. 1489 * 1490 * Otherwise, we will race with the network stack appending new data 1491 * or records onto the socket buffer by using inconsistent/stale 1492 * versions of the field, possibly resulting in socket buffer 1493 * corruption. 1494 * 1495 * By holding the high-level sblock(), we prevent simultaneous 1496 * readers from pulling off the front of the socket buffer. 1497 */ 1498 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 1499 if (uio->uio_td) 1500 uio->uio_td->td_proc->p_stats->p_ru.ru_msgrcv++; 1501 KASSERT(m == so->so_rcv.sb_mb, ("soreceive: m != so->so_rcv.sb_mb")); 1502 SBLASTRECORDCHK(&so->so_rcv); 1503 SBLASTMBUFCHK(&so->so_rcv); 1504 nextrecord = m->m_nextpkt; 1505 if (pr->pr_flags & PR_ADDR) { 1506 KASSERT(m->m_type == MT_SONAME, 1507 ("m->m_type == %d", m->m_type)); 1508 orig_resid = 0; 1509 if (psa != NULL) 1510 *psa = sodupsockaddr(mtod(m, struct sockaddr *), 1511 M_NOWAIT); 1512 if (flags & MSG_PEEK) { 1513 m = m->m_next; 1514 } else { 1515 sbfree(&so->so_rcv, m); 1516 so->so_rcv.sb_mb = m_free(m); 1517 m = so->so_rcv.sb_mb; 1518 sockbuf_pushsync(&so->so_rcv, nextrecord); 1519 } 1520 } 1521 1522 /* 1523 * Process one or more MT_CONTROL mbufs present before any data mbufs 1524 * in the first mbuf chain on the socket buffer. If MSG_PEEK, we 1525 * just copy the data; if !MSG_PEEK, we call into the protocol to 1526 * perform externalization (or freeing if controlp == NULL). 1527 */ 1528 if (m != NULL && m->m_type == MT_CONTROL) { 1529 struct mbuf *cm = NULL, *cmn; 1530 struct mbuf **cme = &cm; 1531 1532 do { 1533 if (flags & MSG_PEEK) { 1534 if (controlp != NULL) { 1535 *controlp = m_copy(m, 0, m->m_len); 1536 controlp = &(*controlp)->m_next; 1537 } 1538 m = m->m_next; 1539 } else { 1540 sbfree(&so->so_rcv, m); 1541 so->so_rcv.sb_mb = m->m_next; 1542 m->m_next = NULL; 1543 *cme = m; 1544 cme = &(*cme)->m_next; 1545 m = so->so_rcv.sb_mb; 1546 } 1547 } while (m != NULL && m->m_type == MT_CONTROL); 1548 if ((flags & MSG_PEEK) == 0) 1549 sockbuf_pushsync(&so->so_rcv, nextrecord); 1550 while (cm != NULL) { 1551 cmn = cm->m_next; 1552 cm->m_next = NULL; 1553 if (pr->pr_domain->dom_externalize != NULL) { 1554 SOCKBUF_UNLOCK(&so->so_rcv); 1555 error = (*pr->pr_domain->dom_externalize) 1556 (cm, controlp); 1557 SOCKBUF_LOCK(&so->so_rcv); 1558 } else if (controlp != NULL) 1559 *controlp = cm; 1560 else 1561 m_freem(cm); 1562 if (controlp != NULL) { 1563 orig_resid = 0; 1564 while (*controlp != NULL) 1565 controlp = &(*controlp)->m_next; 1566 } 1567 cm = cmn; 1568 } 1569 if (so->so_rcv.sb_mb) 1570 nextrecord = so->so_rcv.sb_mb->m_nextpkt; 1571 else 1572 nextrecord = NULL; 1573 orig_resid = 0; 1574 } 1575 if (m != NULL) { 1576 if ((flags & MSG_PEEK) == 0) { 1577 KASSERT(m->m_nextpkt == nextrecord, 1578 ("soreceive: post-control, nextrecord !sync")); 1579 if (nextrecord == NULL) { 1580 KASSERT(so->so_rcv.sb_mb == m, 1581 ("soreceive: post-control, sb_mb!=m")); 1582 KASSERT(so->so_rcv.sb_lastrecord == m, 1583 ("soreceive: post-control, lastrecord!=m")); 1584 } 1585 } 1586 type = m->m_type; 1587 if (type == MT_OOBDATA) 1588 flags |= MSG_OOB; 1589 } else { 1590 if ((flags & MSG_PEEK) == 0) { 1591 KASSERT(so->so_rcv.sb_mb == nextrecord, 1592 ("soreceive: sb_mb != nextrecord")); 1593 if (so->so_rcv.sb_mb == NULL) { 1594 KASSERT(so->so_rcv.sb_lastrecord == NULL, 1595 ("soreceive: sb_lastercord != NULL")); 1596 } 1597 } 1598 } 1599 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 1600 SBLASTRECORDCHK(&so->so_rcv); 1601 SBLASTMBUFCHK(&so->so_rcv); 1602 1603 /* 1604 * Now continue to read any data mbufs off of the head of the socket 1605 * buffer until the read request is satisfied. Note that 'type' is 1606 * used to store the type of any mbuf reads that have happened so far 1607 * such that soreceive() can stop reading if the type changes, which 1608 * causes soreceive() to return only one of regular data and inline 1609 * out-of-band data in a single socket receive operation. 1610 */ 1611 moff = 0; 1612 offset = 0; 1613 while (m != NULL && uio->uio_resid > 0 && error == 0) { 1614 /* 1615 * If the type of mbuf has changed since the last mbuf 1616 * examined ('type'), end the receive operation. 1617 */ 1618 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 1619 if (m->m_type == MT_OOBDATA) { 1620 if (type != MT_OOBDATA) 1621 break; 1622 } else if (type == MT_OOBDATA) 1623 break; 1624 else 1625 KASSERT(m->m_type == MT_DATA, 1626 ("m->m_type == %d", m->m_type)); 1627 so->so_rcv.sb_state &= ~SBS_RCVATMARK; 1628 len = uio->uio_resid; 1629 if (so->so_oobmark && len > so->so_oobmark - offset) 1630 len = so->so_oobmark - offset; 1631 if (len > m->m_len - moff) 1632 len = m->m_len - moff; 1633 /* 1634 * If mp is set, just pass back the mbufs. Otherwise copy 1635 * them out via the uio, then free. Sockbuf must be 1636 * consistent here (points to current mbuf, it points to next 1637 * record) when we drop priority; we must note any additions 1638 * to the sockbuf when we block interrupts again. 1639 */ 1640 if (mp == NULL) { 1641 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 1642 SBLASTRECORDCHK(&so->so_rcv); 1643 SBLASTMBUFCHK(&so->so_rcv); 1644 SOCKBUF_UNLOCK(&so->so_rcv); 1645 #ifdef ZERO_COPY_SOCKETS 1646 if (so_zero_copy_receive) { 1647 int disposable; 1648 1649 if ((m->m_flags & M_EXT) 1650 && (m->m_ext.ext_type == EXT_DISPOSABLE)) 1651 disposable = 1; 1652 else 1653 disposable = 0; 1654 1655 error = uiomoveco(mtod(m, char *) + moff, 1656 (int)len, uio, 1657 disposable); 1658 } else 1659 #endif /* ZERO_COPY_SOCKETS */ 1660 error = uiomove(mtod(m, char *) + moff, (int)len, uio); 1661 SOCKBUF_LOCK(&so->so_rcv); 1662 if (error) 1663 goto release; 1664 } else 1665 uio->uio_resid -= len; 1666 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 1667 if (len == m->m_len - moff) { 1668 if (m->m_flags & M_EOR) 1669 flags |= MSG_EOR; 1670 if (flags & MSG_PEEK) { 1671 m = m->m_next; 1672 moff = 0; 1673 } else { 1674 nextrecord = m->m_nextpkt; 1675 sbfree(&so->so_rcv, m); 1676 if (mp != NULL) { 1677 *mp = m; 1678 mp = &m->m_next; 1679 so->so_rcv.sb_mb = m = m->m_next; 1680 *mp = NULL; 1681 } else { 1682 so->so_rcv.sb_mb = m_free(m); 1683 m = so->so_rcv.sb_mb; 1684 } 1685 sockbuf_pushsync(&so->so_rcv, nextrecord); 1686 SBLASTRECORDCHK(&so->so_rcv); 1687 SBLASTMBUFCHK(&so->so_rcv); 1688 } 1689 } else { 1690 if (flags & MSG_PEEK) 1691 moff += len; 1692 else { 1693 if (mp != NULL) { 1694 int copy_flag; 1695 1696 if (flags & MSG_DONTWAIT) 1697 copy_flag = M_DONTWAIT; 1698 else 1699 copy_flag = M_TRYWAIT; 1700 if (copy_flag == M_TRYWAIT) 1701 SOCKBUF_UNLOCK(&so->so_rcv); 1702 *mp = m_copym(m, 0, len, copy_flag); 1703 if (copy_flag == M_TRYWAIT) 1704 SOCKBUF_LOCK(&so->so_rcv); 1705 if (*mp == NULL) { 1706 /* 1707 * m_copym() couldn't 1708 * allocate an mbuf. Adjust 1709 * uio_resid back (it was 1710 * adjusted down by len 1711 * bytes, which we didn't end 1712 * up "copying" over). 1713 */ 1714 uio->uio_resid += len; 1715 break; 1716 } 1717 } 1718 m->m_data += len; 1719 m->m_len -= len; 1720 so->so_rcv.sb_cc -= len; 1721 } 1722 } 1723 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 1724 if (so->so_oobmark) { 1725 if ((flags & MSG_PEEK) == 0) { 1726 so->so_oobmark -= len; 1727 if (so->so_oobmark == 0) { 1728 so->so_rcv.sb_state |= SBS_RCVATMARK; 1729 break; 1730 } 1731 } else { 1732 offset += len; 1733 if (offset == so->so_oobmark) 1734 break; 1735 } 1736 } 1737 if (flags & MSG_EOR) 1738 break; 1739 /* 1740 * If the MSG_WAITALL flag is set (for non-atomic socket), we 1741 * must not quit until "uio->uio_resid == 0" or an error 1742 * termination. If a signal/timeout occurs, return with a 1743 * short count but without error. Keep sockbuf locked 1744 * against other readers. 1745 */ 1746 while (flags & MSG_WAITALL && m == NULL && uio->uio_resid > 0 && 1747 !sosendallatonce(so) && nextrecord == NULL) { 1748 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 1749 if (so->so_error || so->so_rcv.sb_state & SBS_CANTRCVMORE) 1750 break; 1751 /* 1752 * Notify the protocol that some data has been 1753 * drained before blocking. 1754 */ 1755 if (pr->pr_flags & PR_WANTRCVD) { 1756 SOCKBUF_UNLOCK(&so->so_rcv); 1757 (*pr->pr_usrreqs->pru_rcvd)(so, flags); 1758 SOCKBUF_LOCK(&so->so_rcv); 1759 } 1760 SBLASTRECORDCHK(&so->so_rcv); 1761 SBLASTMBUFCHK(&so->so_rcv); 1762 error = sbwait(&so->so_rcv); 1763 if (error) 1764 goto release; 1765 m = so->so_rcv.sb_mb; 1766 if (m != NULL) 1767 nextrecord = m->m_nextpkt; 1768 } 1769 } 1770 1771 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 1772 if (m != NULL && pr->pr_flags & PR_ATOMIC) { 1773 flags |= MSG_TRUNC; 1774 if ((flags & MSG_PEEK) == 0) 1775 (void) sbdroprecord_locked(&so->so_rcv); 1776 } 1777 if ((flags & MSG_PEEK) == 0) { 1778 if (m == NULL) { 1779 /* 1780 * First part is an inline SB_EMPTY_FIXUP(). Second 1781 * part makes sure sb_lastrecord is up-to-date if 1782 * there is still data in the socket buffer. 1783 */ 1784 so->so_rcv.sb_mb = nextrecord; 1785 if (so->so_rcv.sb_mb == NULL) { 1786 so->so_rcv.sb_mbtail = NULL; 1787 so->so_rcv.sb_lastrecord = NULL; 1788 } else if (nextrecord->m_nextpkt == NULL) 1789 so->so_rcv.sb_lastrecord = nextrecord; 1790 } 1791 SBLASTRECORDCHK(&so->so_rcv); 1792 SBLASTMBUFCHK(&so->so_rcv); 1793 /* 1794 * If soreceive() is being done from the socket callback, 1795 * then don't need to generate ACK to peer to update window, 1796 * since ACK will be generated on return to TCP. 1797 */ 1798 if (!(flags & MSG_SOCALLBCK) && 1799 (pr->pr_flags & PR_WANTRCVD)) { 1800 SOCKBUF_UNLOCK(&so->so_rcv); 1801 (*pr->pr_usrreqs->pru_rcvd)(so, flags); 1802 SOCKBUF_LOCK(&so->so_rcv); 1803 } 1804 } 1805 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 1806 if (orig_resid == uio->uio_resid && orig_resid && 1807 (flags & MSG_EOR) == 0 && (so->so_rcv.sb_state & SBS_CANTRCVMORE) == 0) { 1808 sbunlock(&so->so_rcv); 1809 goto restart; 1810 } 1811 1812 if (flagsp != NULL) 1813 *flagsp |= flags; 1814 release: 1815 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 1816 sbunlock(&so->so_rcv); 1817 out: 1818 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 1819 SOCKBUF_UNLOCK(&so->so_rcv); 1820 return (error); 1821 } 1822 1823 int 1824 soreceive(so, psa, uio, mp0, controlp, flagsp) 1825 struct socket *so; 1826 struct sockaddr **psa; 1827 struct uio *uio; 1828 struct mbuf **mp0; 1829 struct mbuf **controlp; 1830 int *flagsp; 1831 { 1832 1833 /* XXXRW: Temporary debugging. */ 1834 KASSERT(so->so_proto->pr_usrreqs->pru_soreceive != soreceive, 1835 ("soreceive: protocol calls soreceive")); 1836 1837 return (so->so_proto->pr_usrreqs->pru_soreceive(so, psa, uio, mp0, 1838 controlp, flagsp)); 1839 } 1840 1841 int 1842 soshutdown(so, how) 1843 struct socket *so; 1844 int how; 1845 { 1846 struct protosw *pr = so->so_proto; 1847 1848 if (!(how == SHUT_RD || how == SHUT_WR || how == SHUT_RDWR)) 1849 return (EINVAL); 1850 1851 if (how != SHUT_WR) 1852 sorflush(so); 1853 if (how != SHUT_RD) 1854 return ((*pr->pr_usrreqs->pru_shutdown)(so)); 1855 return (0); 1856 } 1857 1858 void 1859 sorflush(so) 1860 struct socket *so; 1861 { 1862 struct sockbuf *sb = &so->so_rcv; 1863 struct protosw *pr = so->so_proto; 1864 struct sockbuf asb; 1865 1866 /* 1867 * XXXRW: This is quite ugly. Previously, this code made a copy of 1868 * the socket buffer, then zero'd the original to clear the buffer 1869 * fields. However, with mutexes in the socket buffer, this causes 1870 * problems. We only clear the zeroable bits of the original; 1871 * however, we have to initialize and destroy the mutex in the copy 1872 * so that dom_dispose() and sbrelease() can lock t as needed. 1873 */ 1874 SOCKBUF_LOCK(sb); 1875 sb->sb_flags |= SB_NOINTR; 1876 (void) sblock(sb, M_WAITOK); 1877 /* 1878 * socantrcvmore_locked() drops the socket buffer mutex so that it 1879 * can safely perform wakeups. Re-acquire the mutex before 1880 * continuing. 1881 */ 1882 socantrcvmore_locked(so); 1883 SOCKBUF_LOCK(sb); 1884 sbunlock(sb); 1885 /* 1886 * Invalidate/clear most of the sockbuf structure, but leave selinfo 1887 * and mutex data unchanged. 1888 */ 1889 bzero(&asb, offsetof(struct sockbuf, sb_startzero)); 1890 bcopy(&sb->sb_startzero, &asb.sb_startzero, 1891 sizeof(*sb) - offsetof(struct sockbuf, sb_startzero)); 1892 bzero(&sb->sb_startzero, 1893 sizeof(*sb) - offsetof(struct sockbuf, sb_startzero)); 1894 SOCKBUF_UNLOCK(sb); 1895 1896 SOCKBUF_LOCK_INIT(&asb, "so_rcv"); 1897 if (pr->pr_flags & PR_RIGHTS && pr->pr_domain->dom_dispose != NULL) 1898 (*pr->pr_domain->dom_dispose)(asb.sb_mb); 1899 sbrelease(&asb, so); 1900 SOCKBUF_LOCK_DESTROY(&asb); 1901 } 1902 1903 /* 1904 * Perhaps this routine, and sooptcopyout(), below, ought to come in an 1905 * additional variant to handle the case where the option value needs to be 1906 * some kind of integer, but not a specific size. In addition to their use 1907 * here, these functions are also called by the protocol-level pr_ctloutput() 1908 * routines. 1909 */ 1910 int 1911 sooptcopyin(sopt, buf, len, minlen) 1912 struct sockopt *sopt; 1913 void *buf; 1914 size_t len; 1915 size_t minlen; 1916 { 1917 size_t valsize; 1918 1919 /* 1920 * If the user gives us more than we wanted, we ignore it, but if we 1921 * don't get the minimum length the caller wants, we return EINVAL. 1922 * On success, sopt->sopt_valsize is set to however much we actually 1923 * retrieved. 1924 */ 1925 if ((valsize = sopt->sopt_valsize) < minlen) 1926 return EINVAL; 1927 if (valsize > len) 1928 sopt->sopt_valsize = valsize = len; 1929 1930 if (sopt->sopt_td != NULL) 1931 return (copyin(sopt->sopt_val, buf, valsize)); 1932 1933 bcopy(sopt->sopt_val, buf, valsize); 1934 return (0); 1935 } 1936 1937 /* 1938 * Kernel version of setsockopt(2). 1939 * 1940 * XXX: optlen is size_t, not socklen_t 1941 */ 1942 int 1943 so_setsockopt(struct socket *so, int level, int optname, void *optval, 1944 size_t optlen) 1945 { 1946 struct sockopt sopt; 1947 1948 sopt.sopt_level = level; 1949 sopt.sopt_name = optname; 1950 sopt.sopt_dir = SOPT_SET; 1951 sopt.sopt_val = optval; 1952 sopt.sopt_valsize = optlen; 1953 sopt.sopt_td = NULL; 1954 return (sosetopt(so, &sopt)); 1955 } 1956 1957 int 1958 sosetopt(so, sopt) 1959 struct socket *so; 1960 struct sockopt *sopt; 1961 { 1962 int error, optval; 1963 struct linger l; 1964 struct timeval tv; 1965 u_long val; 1966 #ifdef MAC 1967 struct mac extmac; 1968 #endif 1969 1970 error = 0; 1971 if (sopt->sopt_level != SOL_SOCKET) { 1972 if (so->so_proto && so->so_proto->pr_ctloutput) 1973 return ((*so->so_proto->pr_ctloutput) 1974 (so, sopt)); 1975 error = ENOPROTOOPT; 1976 } else { 1977 switch (sopt->sopt_name) { 1978 #ifdef INET 1979 case SO_ACCEPTFILTER: 1980 error = do_setopt_accept_filter(so, sopt); 1981 if (error) 1982 goto bad; 1983 break; 1984 #endif 1985 case SO_LINGER: 1986 error = sooptcopyin(sopt, &l, sizeof l, sizeof l); 1987 if (error) 1988 goto bad; 1989 1990 SOCK_LOCK(so); 1991 so->so_linger = l.l_linger; 1992 if (l.l_onoff) 1993 so->so_options |= SO_LINGER; 1994 else 1995 so->so_options &= ~SO_LINGER; 1996 SOCK_UNLOCK(so); 1997 break; 1998 1999 case SO_DEBUG: 2000 case SO_KEEPALIVE: 2001 case SO_DONTROUTE: 2002 case SO_USELOOPBACK: 2003 case SO_BROADCAST: 2004 case SO_REUSEADDR: 2005 case SO_REUSEPORT: 2006 case SO_OOBINLINE: 2007 case SO_TIMESTAMP: 2008 case SO_BINTIME: 2009 case SO_NOSIGPIPE: 2010 error = sooptcopyin(sopt, &optval, sizeof optval, 2011 sizeof optval); 2012 if (error) 2013 goto bad; 2014 SOCK_LOCK(so); 2015 if (optval) 2016 so->so_options |= sopt->sopt_name; 2017 else 2018 so->so_options &= ~sopt->sopt_name; 2019 SOCK_UNLOCK(so); 2020 break; 2021 2022 case SO_SNDBUF: 2023 case SO_RCVBUF: 2024 case SO_SNDLOWAT: 2025 case SO_RCVLOWAT: 2026 error = sooptcopyin(sopt, &optval, sizeof optval, 2027 sizeof optval); 2028 if (error) 2029 goto bad; 2030 2031 /* 2032 * Values < 1 make no sense for any of these options, 2033 * so disallow them. 2034 */ 2035 if (optval < 1) { 2036 error = EINVAL; 2037 goto bad; 2038 } 2039 2040 switch (sopt->sopt_name) { 2041 case SO_SNDBUF: 2042 case SO_RCVBUF: 2043 if (sbreserve(sopt->sopt_name == SO_SNDBUF ? 2044 &so->so_snd : &so->so_rcv, (u_long)optval, 2045 so, curthread) == 0) { 2046 error = ENOBUFS; 2047 goto bad; 2048 } 2049 break; 2050 2051 /* 2052 * Make sure the low-water is never greater than the 2053 * high-water. 2054 */ 2055 case SO_SNDLOWAT: 2056 SOCKBUF_LOCK(&so->so_snd); 2057 so->so_snd.sb_lowat = 2058 (optval > so->so_snd.sb_hiwat) ? 2059 so->so_snd.sb_hiwat : optval; 2060 SOCKBUF_UNLOCK(&so->so_snd); 2061 break; 2062 case SO_RCVLOWAT: 2063 SOCKBUF_LOCK(&so->so_rcv); 2064 so->so_rcv.sb_lowat = 2065 (optval > so->so_rcv.sb_hiwat) ? 2066 so->so_rcv.sb_hiwat : optval; 2067 SOCKBUF_UNLOCK(&so->so_rcv); 2068 break; 2069 } 2070 break; 2071 2072 case SO_SNDTIMEO: 2073 case SO_RCVTIMEO: 2074 #ifdef COMPAT_IA32 2075 if (curthread->td_proc->p_sysent == &ia32_freebsd_sysvec) { 2076 struct timeval32 tv32; 2077 2078 error = sooptcopyin(sopt, &tv32, sizeof tv32, 2079 sizeof tv32); 2080 CP(tv32, tv, tv_sec); 2081 CP(tv32, tv, tv_usec); 2082 } else 2083 #endif 2084 error = sooptcopyin(sopt, &tv, sizeof tv, 2085 sizeof tv); 2086 if (error) 2087 goto bad; 2088 2089 /* assert(hz > 0); */ 2090 if (tv.tv_sec < 0 || tv.tv_sec > INT_MAX / hz || 2091 tv.tv_usec < 0 || tv.tv_usec >= 1000000) { 2092 error = EDOM; 2093 goto bad; 2094 } 2095 /* assert(tick > 0); */ 2096 /* assert(ULONG_MAX - INT_MAX >= 1000000); */ 2097 val = (u_long)(tv.tv_sec * hz) + tv.tv_usec / tick; 2098 if (val > INT_MAX) { 2099 error = EDOM; 2100 goto bad; 2101 } 2102 if (val == 0 && tv.tv_usec != 0) 2103 val = 1; 2104 2105 switch (sopt->sopt_name) { 2106 case SO_SNDTIMEO: 2107 so->so_snd.sb_timeo = val; 2108 break; 2109 case SO_RCVTIMEO: 2110 so->so_rcv.sb_timeo = val; 2111 break; 2112 } 2113 break; 2114 2115 case SO_LABEL: 2116 #ifdef MAC 2117 error = sooptcopyin(sopt, &extmac, sizeof extmac, 2118 sizeof extmac); 2119 if (error) 2120 goto bad; 2121 error = mac_setsockopt_label(sopt->sopt_td->td_ucred, 2122 so, &extmac); 2123 #else 2124 error = EOPNOTSUPP; 2125 #endif 2126 break; 2127 2128 default: 2129 error = ENOPROTOOPT; 2130 break; 2131 } 2132 if (error == 0 && so->so_proto != NULL && 2133 so->so_proto->pr_ctloutput != NULL) { 2134 (void) ((*so->so_proto->pr_ctloutput) 2135 (so, sopt)); 2136 } 2137 } 2138 bad: 2139 return (error); 2140 } 2141 2142 /* 2143 * Helper routine for getsockopt. 2144 */ 2145 int 2146 sooptcopyout(struct sockopt *sopt, const void *buf, size_t len) 2147 { 2148 int error; 2149 size_t valsize; 2150 2151 error = 0; 2152 2153 /* 2154 * Documented get behavior is that we always return a value, possibly 2155 * truncated to fit in the user's buffer. Traditional behavior is 2156 * that we always tell the user precisely how much we copied, rather 2157 * than something useful like the total amount we had available for 2158 * her. Note that this interface is not idempotent; the entire 2159 * answer must generated ahead of time. 2160 */ 2161 valsize = min(len, sopt->sopt_valsize); 2162 sopt->sopt_valsize = valsize; 2163 if (sopt->sopt_val != NULL) { 2164 if (sopt->sopt_td != NULL) 2165 error = copyout(buf, sopt->sopt_val, valsize); 2166 else 2167 bcopy(buf, sopt->sopt_val, valsize); 2168 } 2169 return (error); 2170 } 2171 2172 int 2173 sogetopt(so, sopt) 2174 struct socket *so; 2175 struct sockopt *sopt; 2176 { 2177 int error, optval; 2178 struct linger l; 2179 struct timeval tv; 2180 #ifdef MAC 2181 struct mac extmac; 2182 #endif 2183 2184 error = 0; 2185 if (sopt->sopt_level != SOL_SOCKET) { 2186 if (so->so_proto && so->so_proto->pr_ctloutput) { 2187 return ((*so->so_proto->pr_ctloutput) 2188 (so, sopt)); 2189 } else 2190 return (ENOPROTOOPT); 2191 } else { 2192 switch (sopt->sopt_name) { 2193 #ifdef INET 2194 case SO_ACCEPTFILTER: 2195 error = do_getopt_accept_filter(so, sopt); 2196 break; 2197 #endif 2198 case SO_LINGER: 2199 SOCK_LOCK(so); 2200 l.l_onoff = so->so_options & SO_LINGER; 2201 l.l_linger = so->so_linger; 2202 SOCK_UNLOCK(so); 2203 error = sooptcopyout(sopt, &l, sizeof l); 2204 break; 2205 2206 case SO_USELOOPBACK: 2207 case SO_DONTROUTE: 2208 case SO_DEBUG: 2209 case SO_KEEPALIVE: 2210 case SO_REUSEADDR: 2211 case SO_REUSEPORT: 2212 case SO_BROADCAST: 2213 case SO_OOBINLINE: 2214 case SO_ACCEPTCONN: 2215 case SO_TIMESTAMP: 2216 case SO_BINTIME: 2217 case SO_NOSIGPIPE: 2218 optval = so->so_options & sopt->sopt_name; 2219 integer: 2220 error = sooptcopyout(sopt, &optval, sizeof optval); 2221 break; 2222 2223 case SO_TYPE: 2224 optval = so->so_type; 2225 goto integer; 2226 2227 case SO_ERROR: 2228 SOCK_LOCK(so); 2229 optval = so->so_error; 2230 so->so_error = 0; 2231 SOCK_UNLOCK(so); 2232 goto integer; 2233 2234 case SO_SNDBUF: 2235 optval = so->so_snd.sb_hiwat; 2236 goto integer; 2237 2238 case SO_RCVBUF: 2239 optval = so->so_rcv.sb_hiwat; 2240 goto integer; 2241 2242 case SO_SNDLOWAT: 2243 optval = so->so_snd.sb_lowat; 2244 goto integer; 2245 2246 case SO_RCVLOWAT: 2247 optval = so->so_rcv.sb_lowat; 2248 goto integer; 2249 2250 case SO_SNDTIMEO: 2251 case SO_RCVTIMEO: 2252 optval = (sopt->sopt_name == SO_SNDTIMEO ? 2253 so->so_snd.sb_timeo : so->so_rcv.sb_timeo); 2254 2255 tv.tv_sec = optval / hz; 2256 tv.tv_usec = (optval % hz) * tick; 2257 #ifdef COMPAT_IA32 2258 if (curthread->td_proc->p_sysent == &ia32_freebsd_sysvec) { 2259 struct timeval32 tv32; 2260 2261 CP(tv, tv32, tv_sec); 2262 CP(tv, tv32, tv_usec); 2263 error = sooptcopyout(sopt, &tv32, sizeof tv32); 2264 } else 2265 #endif 2266 error = sooptcopyout(sopt, &tv, sizeof tv); 2267 break; 2268 2269 case SO_LABEL: 2270 #ifdef MAC 2271 error = sooptcopyin(sopt, &extmac, sizeof(extmac), 2272 sizeof(extmac)); 2273 if (error) 2274 return (error); 2275 error = mac_getsockopt_label(sopt->sopt_td->td_ucred, 2276 so, &extmac); 2277 if (error) 2278 return (error); 2279 error = sooptcopyout(sopt, &extmac, sizeof extmac); 2280 #else 2281 error = EOPNOTSUPP; 2282 #endif 2283 break; 2284 2285 case SO_PEERLABEL: 2286 #ifdef MAC 2287 error = sooptcopyin(sopt, &extmac, sizeof(extmac), 2288 sizeof(extmac)); 2289 if (error) 2290 return (error); 2291 error = mac_getsockopt_peerlabel( 2292 sopt->sopt_td->td_ucred, so, &extmac); 2293 if (error) 2294 return (error); 2295 error = sooptcopyout(sopt, &extmac, sizeof extmac); 2296 #else 2297 error = EOPNOTSUPP; 2298 #endif 2299 break; 2300 2301 case SO_LISTENQLIMIT: 2302 optval = so->so_qlimit; 2303 goto integer; 2304 2305 case SO_LISTENQLEN: 2306 optval = so->so_qlen; 2307 goto integer; 2308 2309 case SO_LISTENINCQLEN: 2310 optval = so->so_incqlen; 2311 goto integer; 2312 2313 default: 2314 error = ENOPROTOOPT; 2315 break; 2316 } 2317 return (error); 2318 } 2319 } 2320 2321 /* XXX; prepare mbuf for (__FreeBSD__ < 3) routines. */ 2322 int 2323 soopt_getm(struct sockopt *sopt, struct mbuf **mp) 2324 { 2325 struct mbuf *m, *m_prev; 2326 int sopt_size = sopt->sopt_valsize; 2327 2328 MGET(m, sopt->sopt_td ? M_TRYWAIT : M_DONTWAIT, MT_DATA); 2329 if (m == NULL) 2330 return ENOBUFS; 2331 if (sopt_size > MLEN) { 2332 MCLGET(m, sopt->sopt_td ? M_TRYWAIT : M_DONTWAIT); 2333 if ((m->m_flags & M_EXT) == 0) { 2334 m_free(m); 2335 return ENOBUFS; 2336 } 2337 m->m_len = min(MCLBYTES, sopt_size); 2338 } else { 2339 m->m_len = min(MLEN, sopt_size); 2340 } 2341 sopt_size -= m->m_len; 2342 *mp = m; 2343 m_prev = m; 2344 2345 while (sopt_size) { 2346 MGET(m, sopt->sopt_td ? M_TRYWAIT : M_DONTWAIT, MT_DATA); 2347 if (m == NULL) { 2348 m_freem(*mp); 2349 return ENOBUFS; 2350 } 2351 if (sopt_size > MLEN) { 2352 MCLGET(m, sopt->sopt_td != NULL ? M_TRYWAIT : 2353 M_DONTWAIT); 2354 if ((m->m_flags & M_EXT) == 0) { 2355 m_freem(m); 2356 m_freem(*mp); 2357 return ENOBUFS; 2358 } 2359 m->m_len = min(MCLBYTES, sopt_size); 2360 } else { 2361 m->m_len = min(MLEN, sopt_size); 2362 } 2363 sopt_size -= m->m_len; 2364 m_prev->m_next = m; 2365 m_prev = m; 2366 } 2367 return (0); 2368 } 2369 2370 /* XXX; copyin sopt data into mbuf chain for (__FreeBSD__ < 3) routines. */ 2371 int 2372 soopt_mcopyin(struct sockopt *sopt, struct mbuf *m) 2373 { 2374 struct mbuf *m0 = m; 2375 2376 if (sopt->sopt_val == NULL) 2377 return (0); 2378 while (m != NULL && sopt->sopt_valsize >= m->m_len) { 2379 if (sopt->sopt_td != NULL) { 2380 int error; 2381 2382 error = copyin(sopt->sopt_val, mtod(m, char *), 2383 m->m_len); 2384 if (error != 0) { 2385 m_freem(m0); 2386 return(error); 2387 } 2388 } else 2389 bcopy(sopt->sopt_val, mtod(m, char *), m->m_len); 2390 sopt->sopt_valsize -= m->m_len; 2391 sopt->sopt_val = (char *)sopt->sopt_val + m->m_len; 2392 m = m->m_next; 2393 } 2394 if (m != NULL) /* should be allocated enoughly at ip6_sooptmcopyin() */ 2395 panic("ip6_sooptmcopyin"); 2396 return (0); 2397 } 2398 2399 /* XXX; copyout mbuf chain data into soopt for (__FreeBSD__ < 3) routines. */ 2400 int 2401 soopt_mcopyout(struct sockopt *sopt, struct mbuf *m) 2402 { 2403 struct mbuf *m0 = m; 2404 size_t valsize = 0; 2405 2406 if (sopt->sopt_val == NULL) 2407 return (0); 2408 while (m != NULL && sopt->sopt_valsize >= m->m_len) { 2409 if (sopt->sopt_td != NULL) { 2410 int error; 2411 2412 error = copyout(mtod(m, char *), sopt->sopt_val, 2413 m->m_len); 2414 if (error != 0) { 2415 m_freem(m0); 2416 return(error); 2417 } 2418 } else 2419 bcopy(mtod(m, char *), sopt->sopt_val, m->m_len); 2420 sopt->sopt_valsize -= m->m_len; 2421 sopt->sopt_val = (char *)sopt->sopt_val + m->m_len; 2422 valsize += m->m_len; 2423 m = m->m_next; 2424 } 2425 if (m != NULL) { 2426 /* enough soopt buffer should be given from user-land */ 2427 m_freem(m0); 2428 return(EINVAL); 2429 } 2430 sopt->sopt_valsize = valsize; 2431 return (0); 2432 } 2433 2434 /* 2435 * sohasoutofband(): protocol notifies socket layer of the arrival of new 2436 * out-of-band data, which will then notify socket consumers. 2437 */ 2438 void 2439 sohasoutofband(so) 2440 struct socket *so; 2441 { 2442 if (so->so_sigio != NULL) 2443 pgsigio(&so->so_sigio, SIGURG, 0); 2444 selwakeuppri(&so->so_rcv.sb_sel, PSOCK); 2445 } 2446 2447 int 2448 sopoll(struct socket *so, int events, struct ucred *active_cred, 2449 struct thread *td) 2450 { 2451 2452 /* XXXRW: Temporary debugging. */ 2453 KASSERT(so->so_proto->pr_usrreqs->pru_sopoll != sopoll, 2454 ("sopoll: protocol calls sopoll")); 2455 2456 return (so->so_proto->pr_usrreqs->pru_sopoll(so, events, active_cred, 2457 td)); 2458 } 2459 2460 int 2461 sopoll_generic(struct socket *so, int events, struct ucred *active_cred, 2462 struct thread *td) 2463 { 2464 int revents = 0; 2465 2466 SOCKBUF_LOCK(&so->so_snd); 2467 SOCKBUF_LOCK(&so->so_rcv); 2468 if (events & (POLLIN | POLLRDNORM)) 2469 if (soreadable(so)) 2470 revents |= events & (POLLIN | POLLRDNORM); 2471 2472 if (events & POLLINIGNEOF) 2473 if (so->so_rcv.sb_cc >= so->so_rcv.sb_lowat || 2474 !TAILQ_EMPTY(&so->so_comp) || so->so_error) 2475 revents |= POLLINIGNEOF; 2476 2477 if (events & (POLLOUT | POLLWRNORM)) 2478 if (sowriteable(so)) 2479 revents |= events & (POLLOUT | POLLWRNORM); 2480 2481 if (events & (POLLPRI | POLLRDBAND)) 2482 if (so->so_oobmark || (so->so_rcv.sb_state & SBS_RCVATMARK)) 2483 revents |= events & (POLLPRI | POLLRDBAND); 2484 2485 if (revents == 0) { 2486 if (events & 2487 (POLLIN | POLLINIGNEOF | POLLPRI | POLLRDNORM | 2488 POLLRDBAND)) { 2489 selrecord(td, &so->so_rcv.sb_sel); 2490 so->so_rcv.sb_flags |= SB_SEL; 2491 } 2492 2493 if (events & (POLLOUT | POLLWRNORM)) { 2494 selrecord(td, &so->so_snd.sb_sel); 2495 so->so_snd.sb_flags |= SB_SEL; 2496 } 2497 } 2498 2499 SOCKBUF_UNLOCK(&so->so_rcv); 2500 SOCKBUF_UNLOCK(&so->so_snd); 2501 return (revents); 2502 } 2503 2504 int 2505 soo_kqfilter(struct file *fp, struct knote *kn) 2506 { 2507 struct socket *so = kn->kn_fp->f_data; 2508 struct sockbuf *sb; 2509 2510 switch (kn->kn_filter) { 2511 case EVFILT_READ: 2512 if (so->so_options & SO_ACCEPTCONN) 2513 kn->kn_fop = &solisten_filtops; 2514 else 2515 kn->kn_fop = &soread_filtops; 2516 sb = &so->so_rcv; 2517 break; 2518 case EVFILT_WRITE: 2519 kn->kn_fop = &sowrite_filtops; 2520 sb = &so->so_snd; 2521 break; 2522 default: 2523 return (EINVAL); 2524 } 2525 2526 SOCKBUF_LOCK(sb); 2527 knlist_add(&sb->sb_sel.si_note, kn, 1); 2528 sb->sb_flags |= SB_KNOTE; 2529 SOCKBUF_UNLOCK(sb); 2530 return (0); 2531 } 2532 2533 static void 2534 filt_sordetach(struct knote *kn) 2535 { 2536 struct socket *so = kn->kn_fp->f_data; 2537 2538 SOCKBUF_LOCK(&so->so_rcv); 2539 knlist_remove(&so->so_rcv.sb_sel.si_note, kn, 1); 2540 if (knlist_empty(&so->so_rcv.sb_sel.si_note)) 2541 so->so_rcv.sb_flags &= ~SB_KNOTE; 2542 SOCKBUF_UNLOCK(&so->so_rcv); 2543 } 2544 2545 /*ARGSUSED*/ 2546 static int 2547 filt_soread(struct knote *kn, long hint) 2548 { 2549 struct socket *so; 2550 2551 so = kn->kn_fp->f_data; 2552 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 2553 2554 kn->kn_data = so->so_rcv.sb_cc - so->so_rcv.sb_ctl; 2555 if (so->so_rcv.sb_state & SBS_CANTRCVMORE) { 2556 kn->kn_flags |= EV_EOF; 2557 kn->kn_fflags = so->so_error; 2558 return (1); 2559 } else if (so->so_error) /* temporary udp error */ 2560 return (1); 2561 else if (kn->kn_sfflags & NOTE_LOWAT) 2562 return (kn->kn_data >= kn->kn_sdata); 2563 else 2564 return (so->so_rcv.sb_cc >= so->so_rcv.sb_lowat); 2565 } 2566 2567 static void 2568 filt_sowdetach(struct knote *kn) 2569 { 2570 struct socket *so = kn->kn_fp->f_data; 2571 2572 SOCKBUF_LOCK(&so->so_snd); 2573 knlist_remove(&so->so_snd.sb_sel.si_note, kn, 1); 2574 if (knlist_empty(&so->so_snd.sb_sel.si_note)) 2575 so->so_snd.sb_flags &= ~SB_KNOTE; 2576 SOCKBUF_UNLOCK(&so->so_snd); 2577 } 2578 2579 /*ARGSUSED*/ 2580 static int 2581 filt_sowrite(struct knote *kn, long hint) 2582 { 2583 struct socket *so; 2584 2585 so = kn->kn_fp->f_data; 2586 SOCKBUF_LOCK_ASSERT(&so->so_snd); 2587 kn->kn_data = sbspace(&so->so_snd); 2588 if (so->so_snd.sb_state & SBS_CANTSENDMORE) { 2589 kn->kn_flags |= EV_EOF; 2590 kn->kn_fflags = so->so_error; 2591 return (1); 2592 } else if (so->so_error) /* temporary udp error */ 2593 return (1); 2594 else if (((so->so_state & SS_ISCONNECTED) == 0) && 2595 (so->so_proto->pr_flags & PR_CONNREQUIRED)) 2596 return (0); 2597 else if (kn->kn_sfflags & NOTE_LOWAT) 2598 return (kn->kn_data >= kn->kn_sdata); 2599 else 2600 return (kn->kn_data >= so->so_snd.sb_lowat); 2601 } 2602 2603 /*ARGSUSED*/ 2604 static int 2605 filt_solisten(struct knote *kn, long hint) 2606 { 2607 struct socket *so = kn->kn_fp->f_data; 2608 2609 kn->kn_data = so->so_qlen; 2610 return (! TAILQ_EMPTY(&so->so_comp)); 2611 } 2612 2613 int 2614 socheckuid(struct socket *so, uid_t uid) 2615 { 2616 2617 if (so == NULL) 2618 return (EPERM); 2619 if (so->so_cred->cr_uid != uid) 2620 return (EPERM); 2621 return (0); 2622 } 2623 2624 static int 2625 somaxconn_sysctl(SYSCTL_HANDLER_ARGS) 2626 { 2627 int error; 2628 int val; 2629 2630 val = somaxconn; 2631 error = sysctl_handle_int(oidp, &val, sizeof(int), req); 2632 if (error || !req->newptr ) 2633 return (error); 2634 2635 if (val < 1 || val > USHRT_MAX) 2636 return (EINVAL); 2637 2638 somaxconn = val; 2639 return (0); 2640 } 2641