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 --numopensockets; /* Could be below, but faster here. */ 295 mtx_unlock(&so_global_mtx); 296 if (so->so_rcv.sb_hiwat) 297 (void)chgsbsize(so->so_cred->cr_uidinfo, 298 &so->so_rcv.sb_hiwat, 0, RLIM_INFINITY); 299 if (so->so_snd.sb_hiwat) 300 (void)chgsbsize(so->so_cred->cr_uidinfo, 301 &so->so_snd.sb_hiwat, 0, RLIM_INFINITY); 302 #ifdef INET 303 /* remove acccept filter if one is present. */ 304 if (so->so_accf != NULL) 305 do_setopt_accept_filter(so, NULL); 306 #endif 307 #ifdef MAC 308 mac_destroy_socket(so); 309 #endif 310 crfree(so->so_cred); 311 SOCKBUF_LOCK_DESTROY(&so->so_snd); 312 SOCKBUF_LOCK_DESTROY(&so->so_rcv); 313 uma_zfree(socket_zone, so); 314 } 315 316 /* 317 * socreate returns a socket with a ref count of 1. The socket should be 318 * closed with soclose(). 319 */ 320 int 321 socreate(dom, aso, type, proto, cred, td) 322 int dom; 323 struct socket **aso; 324 int type; 325 int proto; 326 struct ucred *cred; 327 struct thread *td; 328 { 329 struct protosw *prp; 330 struct socket *so; 331 int error; 332 333 if (proto) 334 prp = pffindproto(dom, proto, type); 335 else 336 prp = pffindtype(dom, type); 337 338 if (prp == NULL || prp->pr_usrreqs->pru_attach == NULL || 339 prp->pr_usrreqs->pru_attach == pru_attach_notsupp) 340 return (EPROTONOSUPPORT); 341 342 if (jailed(cred) && jail_socket_unixiproute_only && 343 prp->pr_domain->dom_family != PF_LOCAL && 344 prp->pr_domain->dom_family != PF_INET && 345 prp->pr_domain->dom_family != PF_ROUTE) { 346 return (EPROTONOSUPPORT); 347 } 348 349 if (prp->pr_type != type) 350 return (EPROTOTYPE); 351 so = soalloc(M_WAITOK); 352 if (so == NULL) 353 return (ENOBUFS); 354 355 TAILQ_INIT(&so->so_incomp); 356 TAILQ_INIT(&so->so_comp); 357 so->so_type = type; 358 so->so_cred = crhold(cred); 359 so->so_proto = prp; 360 #ifdef MAC 361 mac_create_socket(cred, so); 362 #endif 363 knlist_init(&so->so_rcv.sb_sel.si_note, SOCKBUF_MTX(&so->so_rcv), 364 NULL, NULL, NULL); 365 knlist_init(&so->so_snd.sb_sel.si_note, SOCKBUF_MTX(&so->so_snd), 366 NULL, NULL, NULL); 367 so->so_count = 1; 368 error = (*prp->pr_usrreqs->pru_attach)(so, proto, td); 369 if (error) { 370 sodealloc(so); 371 return (error); 372 } 373 *aso = so; 374 return (0); 375 } 376 377 #ifdef REGRESSION 378 static int regression_sonewconn_earlytest = 1; 379 SYSCTL_INT(_regression, OID_AUTO, sonewconn_earlytest, CTLFLAG_RW, 380 ®ression_sonewconn_earlytest, 0, "Perform early sonewconn limit test"); 381 #endif 382 383 /* 384 * When an attempt at a new connection is noted on a socket which accepts 385 * connections, sonewconn is called. If the connection is possible (subject 386 * to space constraints, etc.) then we allocate a new structure, propoerly 387 * linked into the data structure of the original socket, and return this. 388 * Connstatus may be 0, or SO_ISCONFIRMING, or SO_ISCONNECTED. 389 * 390 * Note: the ref count on the socket is 0 on return. 391 */ 392 struct socket * 393 sonewconn(head, connstatus) 394 register struct socket *head; 395 int connstatus; 396 { 397 register struct socket *so; 398 int over; 399 400 ACCEPT_LOCK(); 401 over = (head->so_qlen > 3 * head->so_qlimit / 2); 402 ACCEPT_UNLOCK(); 403 #ifdef REGRESSION 404 if (regression_sonewconn_earlytest && over) 405 #else 406 if (over) 407 #endif 408 return (NULL); 409 so = soalloc(M_NOWAIT); 410 if (so == NULL) 411 return (NULL); 412 if ((head->so_options & SO_ACCEPTFILTER) != 0) 413 connstatus = 0; 414 so->so_head = head; 415 so->so_type = head->so_type; 416 so->so_options = head->so_options &~ SO_ACCEPTCONN; 417 so->so_linger = head->so_linger; 418 so->so_state = head->so_state | SS_NOFDREF; 419 so->so_proto = head->so_proto; 420 so->so_timeo = head->so_timeo; 421 so->so_cred = crhold(head->so_cred); 422 #ifdef MAC 423 SOCK_LOCK(head); 424 mac_create_socket_from_socket(head, so); 425 SOCK_UNLOCK(head); 426 #endif 427 knlist_init(&so->so_rcv.sb_sel.si_note, SOCKBUF_MTX(&so->so_rcv), 428 NULL, NULL, NULL); 429 knlist_init(&so->so_snd.sb_sel.si_note, SOCKBUF_MTX(&so->so_snd), 430 NULL, NULL, NULL); 431 if (soreserve(so, head->so_snd.sb_hiwat, head->so_rcv.sb_hiwat) || 432 (*so->so_proto->pr_usrreqs->pru_attach)(so, 0, NULL)) { 433 sodealloc(so); 434 return (NULL); 435 } 436 so->so_state |= connstatus; 437 ACCEPT_LOCK(); 438 if (connstatus) { 439 TAILQ_INSERT_TAIL(&head->so_comp, so, so_list); 440 so->so_qstate |= SQ_COMP; 441 head->so_qlen++; 442 } else { 443 /* 444 * Keep removing sockets from the head until there's room for 445 * us to insert on the tail. In pre-locking revisions, this 446 * was a simple if(), but as we could be racing with other 447 * threads and soabort() requires dropping locks, we must 448 * loop waiting for the condition to be true. 449 */ 450 while (head->so_incqlen > head->so_qlimit) { 451 struct socket *sp; 452 sp = TAILQ_FIRST(&head->so_incomp); 453 TAILQ_REMOVE(&head->so_incomp, sp, so_list); 454 head->so_incqlen--; 455 sp->so_qstate &= ~SQ_INCOMP; 456 sp->so_head = NULL; 457 ACCEPT_UNLOCK(); 458 soabort(sp); 459 ACCEPT_LOCK(); 460 } 461 TAILQ_INSERT_TAIL(&head->so_incomp, so, so_list); 462 so->so_qstate |= SQ_INCOMP; 463 head->so_incqlen++; 464 } 465 ACCEPT_UNLOCK(); 466 if (connstatus) { 467 sorwakeup(head); 468 wakeup_one(&head->so_timeo); 469 } 470 return (so); 471 } 472 473 int 474 sobind(so, nam, td) 475 struct socket *so; 476 struct sockaddr *nam; 477 struct thread *td; 478 { 479 480 return ((*so->so_proto->pr_usrreqs->pru_bind)(so, nam, td)); 481 } 482 483 /* 484 * solisten() transitions a socket from a non-listening state to a listening 485 * state, but can also be used to update the listen queue depth on an 486 * existing listen socket. The protocol will call back into the sockets 487 * layer using solisten_proto_check() and solisten_proto() to check and set 488 * socket-layer listen state. Call backs are used so that the protocol can 489 * acquire both protocol and socket layer locks in whatever order is required 490 * by the protocol. 491 * 492 * Protocol implementors are advised to hold the socket lock across the 493 * socket-layer test and set to avoid races at the socket layer. 494 */ 495 int 496 solisten(so, backlog, td) 497 struct socket *so; 498 int backlog; 499 struct thread *td; 500 { 501 502 return ((*so->so_proto->pr_usrreqs->pru_listen)(so, backlog, td)); 503 } 504 505 int 506 solisten_proto_check(so) 507 struct socket *so; 508 { 509 510 SOCK_LOCK_ASSERT(so); 511 512 if (so->so_state & (SS_ISCONNECTED | SS_ISCONNECTING | 513 SS_ISDISCONNECTING)) 514 return (EINVAL); 515 return (0); 516 } 517 518 void 519 solisten_proto(so, backlog) 520 struct socket *so; 521 int backlog; 522 { 523 524 SOCK_LOCK_ASSERT(so); 525 526 if (backlog < 0 || backlog > somaxconn) 527 backlog = somaxconn; 528 so->so_qlimit = backlog; 529 so->so_options |= SO_ACCEPTCONN; 530 } 531 532 /* 533 * Attempt to free a socket. This should really be sotryfree(). 534 * 535 * sofree() will succeed if: 536 * 537 * - There are no outstanding file descriptor references or related consumers 538 * (so_count == 0). 539 * 540 * - The socket has been closed by user space, if ever open (SS_NOFDREF). 541 * 542 * - The protocol does not have an outstanding strong reference on the socket 543 * (SS_PROTOREF). 544 * 545 * - The socket is not in a completed connection queue, so a process has been 546 * notified that it is present. If it is removed, the user process may 547 * block in accept() despite select() saying the socket was ready. 548 * 549 * Otherwise, it will quietly abort so that a future call to sofree(), when 550 * conditions are right, can succeed. 551 */ 552 void 553 sofree(so) 554 struct socket *so; 555 { 556 struct protosw *pr = so->so_proto; 557 struct socket *head; 558 559 ACCEPT_LOCK_ASSERT(); 560 SOCK_LOCK_ASSERT(so); 561 562 if ((so->so_state & SS_NOFDREF) == 0 || so->so_count != 0 || 563 (so->so_state & SS_PROTOREF) || (so->so_qstate & SQ_COMP)) { 564 SOCK_UNLOCK(so); 565 ACCEPT_UNLOCK(); 566 return; 567 } 568 569 head = so->so_head; 570 if (head != NULL) { 571 KASSERT((so->so_qstate & SQ_COMP) != 0 || 572 (so->so_qstate & SQ_INCOMP) != 0, 573 ("sofree: so_head != NULL, but neither SQ_COMP nor " 574 "SQ_INCOMP")); 575 KASSERT((so->so_qstate & SQ_COMP) == 0 || 576 (so->so_qstate & SQ_INCOMP) == 0, 577 ("sofree: so->so_qstate is SQ_COMP and also SQ_INCOMP")); 578 TAILQ_REMOVE(&head->so_incomp, so, so_list); 579 head->so_incqlen--; 580 so->so_qstate &= ~SQ_INCOMP; 581 so->so_head = NULL; 582 } 583 KASSERT((so->so_qstate & SQ_COMP) == 0 && 584 (so->so_qstate & SQ_INCOMP) == 0, 585 ("sofree: so_head == NULL, but still SQ_COMP(%d) or SQ_INCOMP(%d)", 586 so->so_qstate & SQ_COMP, so->so_qstate & SQ_INCOMP)); 587 SOCK_UNLOCK(so); 588 ACCEPT_UNLOCK(); 589 590 /* 591 * From this point on, we assume that no other references to this 592 * socket exist anywhere else in the stack. Therefore, no locks need 593 * to be acquired or held. 594 * 595 * We used to do a lot of socket buffer and socket locking here, as 596 * well as invoke sorflush() and perform wakeups. The direct call to 597 * dom_dispose() and sbrelease_internal() are an inlining of what was 598 * necessary from sorflush(). 599 * 600 * Notice that the socket buffer and kqueue state are torn down 601 * before calling pru_detach. This means that protocols shold not 602 * assume they can perform socket wakeups, etc, in their detach 603 * code. 604 */ 605 KASSERT((so->so_snd.sb_flags & SB_LOCK) == 0, ("sofree: snd sblock")); 606 KASSERT((so->so_rcv.sb_flags & SB_LOCK) == 0, ("sofree: rcv sblock")); 607 sbdestroy(&so->so_snd, so); 608 if (pr->pr_flags & PR_RIGHTS && pr->pr_domain->dom_dispose != NULL) 609 (*pr->pr_domain->dom_dispose)(so->so_rcv.sb_mb); 610 sbdestroy(&so->so_rcv, so); 611 if (pr->pr_usrreqs->pru_detach != NULL) 612 (*pr->pr_usrreqs->pru_detach)(so); 613 knlist_destroy(&so->so_rcv.sb_sel.si_note); 614 knlist_destroy(&so->so_snd.sb_sel.si_note); 615 sodealloc(so); 616 } 617 618 /* 619 * Close a socket on last file table reference removal. Initiate disconnect 620 * if connected. Free socket when disconnect complete. 621 * 622 * This function will sorele() the socket. Note that soclose() may be called 623 * prior to the ref count reaching zero. The actual socket structure will 624 * not be freed until the ref count reaches zero. 625 */ 626 int 627 soclose(so) 628 struct socket *so; 629 { 630 int error = 0; 631 632 KASSERT(!(so->so_state & SS_NOFDREF), ("soclose: SS_NOFDREF on enter")); 633 634 funsetown(&so->so_sigio); 635 if (so->so_options & SO_ACCEPTCONN) { 636 struct socket *sp; 637 ACCEPT_LOCK(); 638 while ((sp = TAILQ_FIRST(&so->so_incomp)) != NULL) { 639 TAILQ_REMOVE(&so->so_incomp, sp, so_list); 640 so->so_incqlen--; 641 sp->so_qstate &= ~SQ_INCOMP; 642 sp->so_head = NULL; 643 ACCEPT_UNLOCK(); 644 soabort(sp); 645 ACCEPT_LOCK(); 646 } 647 while ((sp = TAILQ_FIRST(&so->so_comp)) != NULL) { 648 TAILQ_REMOVE(&so->so_comp, sp, so_list); 649 so->so_qlen--; 650 sp->so_qstate &= ~SQ_COMP; 651 sp->so_head = NULL; 652 ACCEPT_UNLOCK(); 653 soabort(sp); 654 ACCEPT_LOCK(); 655 } 656 ACCEPT_UNLOCK(); 657 } 658 if (so->so_state & SS_ISCONNECTED) { 659 if ((so->so_state & SS_ISDISCONNECTING) == 0) { 660 error = sodisconnect(so); 661 if (error) 662 goto drop; 663 } 664 if (so->so_options & SO_LINGER) { 665 if ((so->so_state & SS_ISDISCONNECTING) && 666 (so->so_state & SS_NBIO)) 667 goto drop; 668 while (so->so_state & SS_ISCONNECTED) { 669 error = tsleep(&so->so_timeo, 670 PSOCK | PCATCH, "soclos", so->so_linger * hz); 671 if (error) 672 break; 673 } 674 } 675 } 676 677 drop: 678 if (so->so_proto->pr_usrreqs->pru_close != NULL) 679 (*so->so_proto->pr_usrreqs->pru_close)(so); 680 ACCEPT_LOCK(); 681 SOCK_LOCK(so); 682 KASSERT((so->so_state & SS_NOFDREF) == 0, ("soclose: NOFDREF")); 683 so->so_state |= SS_NOFDREF; 684 sorele(so); 685 return (error); 686 } 687 688 /* 689 * soabort() is used to abruptly tear down a connection, such as when a 690 * resource limit is reached (listen queue depth exceeded), or if a listen 691 * socket is closed while there are sockets waiting to be accepted. 692 * 693 * This interface is tricky, because it is called on an unreferenced socket, 694 * and must be called only by a thread that has actually removed the socket 695 * from the listen queue it was on, or races with other threads are risked. 696 * 697 * This interface will call into the protocol code, so must not be called 698 * with any socket locks held. Protocols do call it while holding their own 699 * recursible protocol mutexes, but this is something that should be subject 700 * to review in the future. 701 */ 702 void 703 soabort(so) 704 struct socket *so; 705 { 706 707 /* 708 * In as much as is possible, assert that no references to this 709 * socket are held. This is not quite the same as asserting that the 710 * current thread is responsible for arranging for no references, but 711 * is as close as we can get for now. 712 */ 713 KASSERT(so->so_count == 0, ("soabort: so_count")); 714 KASSERT((so->so_state & SS_PROTOREF) == 0, ("soabort: SS_PROTOREF")); 715 KASSERT(so->so_state & SS_NOFDREF, ("soabort: !SS_NOFDREF")); 716 KASSERT((so->so_state & SQ_COMP) == 0, ("soabort: SQ_COMP")); 717 KASSERT((so->so_state & SQ_INCOMP) == 0, ("soabort: SQ_INCOMP")); 718 719 if (so->so_proto->pr_usrreqs->pru_abort != NULL) 720 (*so->so_proto->pr_usrreqs->pru_abort)(so); 721 ACCEPT_LOCK(); 722 SOCK_LOCK(so); 723 sofree(so); 724 } 725 726 int 727 soaccept(so, nam) 728 struct socket *so; 729 struct sockaddr **nam; 730 { 731 int error; 732 733 SOCK_LOCK(so); 734 KASSERT((so->so_state & SS_NOFDREF) != 0, ("soaccept: !NOFDREF")); 735 so->so_state &= ~SS_NOFDREF; 736 SOCK_UNLOCK(so); 737 error = (*so->so_proto->pr_usrreqs->pru_accept)(so, nam); 738 return (error); 739 } 740 741 int 742 soconnect(so, nam, td) 743 struct socket *so; 744 struct sockaddr *nam; 745 struct thread *td; 746 { 747 int error; 748 749 if (so->so_options & SO_ACCEPTCONN) 750 return (EOPNOTSUPP); 751 /* 752 * If protocol is connection-based, can only connect once. 753 * Otherwise, if connected, try to disconnect first. This allows 754 * user to disconnect by connecting to, e.g., a null address. 755 */ 756 if (so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING) && 757 ((so->so_proto->pr_flags & PR_CONNREQUIRED) || 758 (error = sodisconnect(so)))) { 759 error = EISCONN; 760 } else { 761 /* 762 * Prevent accumulated error from previous connection from 763 * biting us. 764 */ 765 so->so_error = 0; 766 error = (*so->so_proto->pr_usrreqs->pru_connect)(so, nam, td); 767 } 768 769 return (error); 770 } 771 772 int 773 soconnect2(so1, so2) 774 struct socket *so1; 775 struct socket *so2; 776 { 777 778 return ((*so1->so_proto->pr_usrreqs->pru_connect2)(so1, so2)); 779 } 780 781 int 782 sodisconnect(so) 783 struct socket *so; 784 { 785 int error; 786 787 if ((so->so_state & SS_ISCONNECTED) == 0) 788 return (ENOTCONN); 789 if (so->so_state & SS_ISDISCONNECTING) 790 return (EALREADY); 791 error = (*so->so_proto->pr_usrreqs->pru_disconnect)(so); 792 return (error); 793 } 794 795 #ifdef ZERO_COPY_SOCKETS 796 struct so_zerocopy_stats{ 797 int size_ok; 798 int align_ok; 799 int found_ifp; 800 }; 801 struct so_zerocopy_stats so_zerocp_stats = {0,0,0}; 802 #include <netinet/in.h> 803 #include <net/route.h> 804 #include <netinet/in_pcb.h> 805 #include <vm/vm.h> 806 #include <vm/vm_page.h> 807 #include <vm/vm_object.h> 808 #endif /*ZERO_COPY_SOCKETS*/ 809 810 /* 811 * sosend_copyin() accepts a uio and prepares an mbuf chain holding part or 812 * all of the data referenced by the uio. If desired, it uses zero-copy. 813 * *space will be updated to reflect data copied in. 814 * 815 * NB: If atomic I/O is requested, the caller must already have checked that 816 * space can hold resid bytes. 817 * 818 * NB: In the event of an error, the caller may need to free the partial 819 * chain pointed to by *mpp. The contents of both *uio and *space may be 820 * modified even in the case of an error. 821 */ 822 static int 823 sosend_copyin(struct uio *uio, struct mbuf **retmp, int atomic, long *space, 824 int flags) 825 { 826 struct mbuf *m, **mp, *top; 827 long len, resid; 828 int error; 829 #ifdef ZERO_COPY_SOCKETS 830 int cow_send; 831 #endif 832 833 *retmp = top = NULL; 834 mp = ⊤ 835 len = 0; 836 resid = uio->uio_resid; 837 error = 0; 838 do { 839 #ifdef ZERO_COPY_SOCKETS 840 cow_send = 0; 841 #endif /* ZERO_COPY_SOCKETS */ 842 if (resid >= MINCLSIZE) { 843 #ifdef ZERO_COPY_SOCKETS 844 if (top == NULL) { 845 MGETHDR(m, M_TRYWAIT, MT_DATA); 846 if (m == NULL) { 847 error = ENOBUFS; 848 goto out; 849 } 850 m->m_pkthdr.len = 0; 851 m->m_pkthdr.rcvif = NULL; 852 } else { 853 MGET(m, M_TRYWAIT, MT_DATA); 854 if (m == NULL) { 855 error = ENOBUFS; 856 goto out; 857 } 858 } 859 if (so_zero_copy_send && 860 resid>=PAGE_SIZE && 861 *space>=PAGE_SIZE && 862 uio->uio_iov->iov_len>=PAGE_SIZE) { 863 so_zerocp_stats.size_ok++; 864 so_zerocp_stats.align_ok++; 865 cow_send = socow_setup(m, uio); 866 len = cow_send; 867 } 868 if (!cow_send) { 869 MCLGET(m, M_TRYWAIT); 870 if ((m->m_flags & M_EXT) == 0) { 871 m_free(m); 872 m = NULL; 873 } else { 874 len = min(min(MCLBYTES, resid), 875 *space); 876 } 877 } 878 #else /* ZERO_COPY_SOCKETS */ 879 if (top == NULL) { 880 m = m_getcl(M_TRYWAIT, MT_DATA, M_PKTHDR); 881 m->m_pkthdr.len = 0; 882 m->m_pkthdr.rcvif = NULL; 883 } else 884 m = m_getcl(M_TRYWAIT, MT_DATA, 0); 885 len = min(min(MCLBYTES, resid), *space); 886 #endif /* ZERO_COPY_SOCKETS */ 887 } else { 888 if (top == NULL) { 889 m = m_gethdr(M_TRYWAIT, MT_DATA); 890 m->m_pkthdr.len = 0; 891 m->m_pkthdr.rcvif = NULL; 892 893 len = min(min(MHLEN, resid), *space); 894 /* 895 * For datagram protocols, leave room 896 * for protocol headers in first mbuf. 897 */ 898 if (atomic && m && len < MHLEN) 899 MH_ALIGN(m, len); 900 } else { 901 m = m_get(M_TRYWAIT, MT_DATA); 902 len = min(min(MLEN, resid), *space); 903 } 904 } 905 if (m == NULL) { 906 error = ENOBUFS; 907 goto out; 908 } 909 910 *space -= len; 911 #ifdef ZERO_COPY_SOCKETS 912 if (cow_send) 913 error = 0; 914 else 915 #endif /* ZERO_COPY_SOCKETS */ 916 error = uiomove(mtod(m, void *), (int)len, uio); 917 resid = uio->uio_resid; 918 m->m_len = len; 919 *mp = m; 920 top->m_pkthdr.len += len; 921 if (error) 922 goto out; 923 mp = &m->m_next; 924 if (resid <= 0) { 925 if (flags & MSG_EOR) 926 top->m_flags |= M_EOR; 927 break; 928 } 929 } while (*space > 0 && atomic); 930 out: 931 *retmp = top; 932 return (error); 933 } 934 935 #define SBLOCKWAIT(f) (((f) & MSG_DONTWAIT) ? M_NOWAIT : M_WAITOK) 936 937 int 938 sosend_dgram(so, addr, uio, top, control, flags, td) 939 struct socket *so; 940 struct sockaddr *addr; 941 struct uio *uio; 942 struct mbuf *top; 943 struct mbuf *control; 944 int flags; 945 struct thread *td; 946 { 947 long space, resid; 948 int clen = 0, error, dontroute; 949 int atomic = sosendallatonce(so) || top; 950 951 KASSERT(so->so_type == SOCK_DGRAM, ("sodgram_send: !SOCK_DGRAM")); 952 KASSERT(so->so_proto->pr_flags & PR_ATOMIC, 953 ("sodgram_send: !PR_ATOMIC")); 954 955 if (uio != NULL) 956 resid = uio->uio_resid; 957 else 958 resid = top->m_pkthdr.len; 959 /* 960 * In theory resid should be unsigned. However, space must be 961 * signed, as it might be less than 0 if we over-committed, and we 962 * must use a signed comparison of space and resid. On the other 963 * hand, a negative resid causes us to loop sending 0-length 964 * segments to the protocol. 965 * 966 * Also check to make sure that MSG_EOR isn't used on SOCK_STREAM 967 * type sockets since that's an error. 968 */ 969 if (resid < 0) { 970 error = EINVAL; 971 goto out; 972 } 973 974 dontroute = 975 (flags & MSG_DONTROUTE) && (so->so_options & SO_DONTROUTE) == 0; 976 if (td != NULL) 977 td->td_proc->p_stats->p_ru.ru_msgsnd++; 978 if (control != NULL) 979 clen = control->m_len; 980 981 SOCKBUF_LOCK(&so->so_snd); 982 if (so->so_snd.sb_state & SBS_CANTSENDMORE) { 983 SOCKBUF_UNLOCK(&so->so_snd); 984 error = EPIPE; 985 goto out; 986 } 987 if (so->so_error) { 988 error = so->so_error; 989 so->so_error = 0; 990 SOCKBUF_UNLOCK(&so->so_snd); 991 goto out; 992 } 993 if ((so->so_state & SS_ISCONNECTED) == 0) { 994 /* 995 * `sendto' and `sendmsg' is allowed on a connection-based 996 * socket if it supports implied connect. Return ENOTCONN if 997 * not connected and no address is supplied. 998 */ 999 if ((so->so_proto->pr_flags & PR_CONNREQUIRED) && 1000 (so->so_proto->pr_flags & PR_IMPLOPCL) == 0) { 1001 if ((so->so_state & SS_ISCONFIRMING) == 0 && 1002 !(resid == 0 && clen != 0)) { 1003 SOCKBUF_UNLOCK(&so->so_snd); 1004 error = ENOTCONN; 1005 goto out; 1006 } 1007 } else if (addr == NULL) { 1008 if (so->so_proto->pr_flags & PR_CONNREQUIRED) 1009 error = ENOTCONN; 1010 else 1011 error = EDESTADDRREQ; 1012 SOCKBUF_UNLOCK(&so->so_snd); 1013 goto out; 1014 } 1015 } 1016 1017 /* 1018 * Do we need MSG_OOB support in SOCK_DGRAM? Signs here may be a 1019 * problem and need fixing. 1020 */ 1021 space = sbspace(&so->so_snd); 1022 if (flags & MSG_OOB) 1023 space += 1024; 1024 space -= clen; 1025 if (resid > space) { 1026 error = EMSGSIZE; 1027 goto out; 1028 } 1029 SOCKBUF_UNLOCK(&so->so_snd); 1030 if (uio == NULL) { 1031 resid = 0; 1032 if (flags & MSG_EOR) 1033 top->m_flags |= M_EOR; 1034 } else { 1035 error = sosend_copyin(uio, &top, atomic, &space, flags); 1036 if (error) 1037 goto out; 1038 resid = uio->uio_resid; 1039 } 1040 KASSERT(resid == 0, ("sosend_dgram: resid != 0")); 1041 /* 1042 * XXXRW: Frobbing SO_DONTROUTE here is even worse without sblock 1043 * than with. 1044 */ 1045 if (dontroute) { 1046 SOCK_LOCK(so); 1047 so->so_options |= SO_DONTROUTE; 1048 SOCK_UNLOCK(so); 1049 } 1050 /* 1051 * XXX all the SBS_CANTSENDMORE checks previously done could be out 1052 * of date. We could have recieved a reset packet in an interrupt or 1053 * maybe we slept while doing page faults in uiomove() etc. We could 1054 * probably recheck again inside the locking protection here, but 1055 * there are probably other places that this also happens. We must 1056 * rethink this. 1057 */ 1058 error = (*so->so_proto->pr_usrreqs->pru_send)(so, 1059 (flags & MSG_OOB) ? PRUS_OOB : 1060 /* 1061 * If the user set MSG_EOF, the protocol understands this flag and 1062 * nothing left to send then use PRU_SEND_EOF instead of PRU_SEND. 1063 */ 1064 ((flags & MSG_EOF) && 1065 (so->so_proto->pr_flags & PR_IMPLOPCL) && 1066 (resid <= 0)) ? 1067 PRUS_EOF : 1068 /* If there is more to send set PRUS_MORETOCOME */ 1069 (resid > 0 && space > 0) ? PRUS_MORETOCOME : 0, 1070 top, addr, control, td); 1071 if (dontroute) { 1072 SOCK_LOCK(so); 1073 so->so_options &= ~SO_DONTROUTE; 1074 SOCK_UNLOCK(so); 1075 } 1076 clen = 0; 1077 control = NULL; 1078 top = NULL; 1079 out: 1080 if (top != NULL) 1081 m_freem(top); 1082 if (control != NULL) 1083 m_freem(control); 1084 return (error); 1085 } 1086 1087 /* 1088 * Send on a socket. If send must go all at once and message is larger than 1089 * send buffering, then hard error. Lock against other senders. If must go 1090 * all at once and not enough room now, then inform user that this would 1091 * block and do nothing. Otherwise, if nonblocking, send as much as 1092 * possible. The data to be sent is described by "uio" if nonzero, otherwise 1093 * by the mbuf chain "top" (which must be null if uio is not). Data provided 1094 * in mbuf chain must be small enough to send all at once. 1095 * 1096 * Returns nonzero on error, timeout or signal; callers must check for short 1097 * counts if EINTR/ERESTART are returned. Data and control buffers are freed 1098 * on return. 1099 */ 1100 #define snderr(errno) { error = (errno); goto release; } 1101 int 1102 sosend_generic(so, addr, uio, top, control, flags, td) 1103 struct socket *so; 1104 struct sockaddr *addr; 1105 struct uio *uio; 1106 struct mbuf *top; 1107 struct mbuf *control; 1108 int flags; 1109 struct thread *td; 1110 { 1111 long space, resid; 1112 int clen = 0, error, dontroute; 1113 int atomic = sosendallatonce(so) || top; 1114 1115 if (uio != NULL) 1116 resid = uio->uio_resid; 1117 else 1118 resid = top->m_pkthdr.len; 1119 /* 1120 * In theory resid should be unsigned. However, space must be 1121 * signed, as it might be less than 0 if we over-committed, and we 1122 * must use a signed comparison of space and resid. On the other 1123 * hand, a negative resid causes us to loop sending 0-length 1124 * segments to the protocol. 1125 * 1126 * Also check to make sure that MSG_EOR isn't used on SOCK_STREAM 1127 * type sockets since that's an error. 1128 */ 1129 if (resid < 0 || (so->so_type == SOCK_STREAM && (flags & MSG_EOR))) { 1130 error = EINVAL; 1131 goto out; 1132 } 1133 1134 dontroute = 1135 (flags & MSG_DONTROUTE) && (so->so_options & SO_DONTROUTE) == 0 && 1136 (so->so_proto->pr_flags & PR_ATOMIC); 1137 if (td != NULL) 1138 td->td_proc->p_stats->p_ru.ru_msgsnd++; 1139 if (control != NULL) 1140 clen = control->m_len; 1141 1142 SOCKBUF_LOCK(&so->so_snd); 1143 restart: 1144 SOCKBUF_LOCK_ASSERT(&so->so_snd); 1145 error = sblock(&so->so_snd, SBLOCKWAIT(flags)); 1146 if (error) 1147 goto out_locked; 1148 do { 1149 SOCKBUF_LOCK_ASSERT(&so->so_snd); 1150 if (so->so_snd.sb_state & SBS_CANTSENDMORE) 1151 snderr(EPIPE); 1152 if (so->so_error) { 1153 error = so->so_error; 1154 so->so_error = 0; 1155 goto release; 1156 } 1157 if ((so->so_state & SS_ISCONNECTED) == 0) { 1158 /* 1159 * `sendto' and `sendmsg' is allowed on a connection- 1160 * based socket if it supports implied connect. 1161 * Return ENOTCONN if not connected and no address is 1162 * supplied. 1163 */ 1164 if ((so->so_proto->pr_flags & PR_CONNREQUIRED) && 1165 (so->so_proto->pr_flags & PR_IMPLOPCL) == 0) { 1166 if ((so->so_state & SS_ISCONFIRMING) == 0 && 1167 !(resid == 0 && clen != 0)) 1168 snderr(ENOTCONN); 1169 } else if (addr == NULL) 1170 snderr(so->so_proto->pr_flags & PR_CONNREQUIRED ? 1171 ENOTCONN : EDESTADDRREQ); 1172 } 1173 space = sbspace(&so->so_snd); 1174 if (flags & MSG_OOB) 1175 space += 1024; 1176 if ((atomic && resid > so->so_snd.sb_hiwat) || 1177 clen > so->so_snd.sb_hiwat) 1178 snderr(EMSGSIZE); 1179 if (space < resid + clen && 1180 (atomic || space < so->so_snd.sb_lowat || space < clen)) { 1181 if ((so->so_state & SS_NBIO) || (flags & MSG_NBIO)) 1182 snderr(EWOULDBLOCK); 1183 sbunlock(&so->so_snd); 1184 error = sbwait(&so->so_snd); 1185 if (error) 1186 goto out_locked; 1187 goto restart; 1188 } 1189 SOCKBUF_UNLOCK(&so->so_snd); 1190 space -= clen; 1191 do { 1192 if (uio == NULL) { 1193 resid = 0; 1194 if (flags & MSG_EOR) 1195 top->m_flags |= M_EOR; 1196 } else { 1197 error = sosend_copyin(uio, &top, atomic, 1198 &space, flags); 1199 if (error != 0) { 1200 SOCKBUF_LOCK(&so->so_snd); 1201 goto release; 1202 } 1203 resid = uio->uio_resid; 1204 } 1205 if (dontroute) { 1206 SOCK_LOCK(so); 1207 so->so_options |= SO_DONTROUTE; 1208 SOCK_UNLOCK(so); 1209 } 1210 /* 1211 * XXX all the SBS_CANTSENDMORE checks previously 1212 * done could be out of date. We could have recieved 1213 * a reset packet in an interrupt or maybe we slept 1214 * while doing page faults in uiomove() etc. We 1215 * could probably recheck again inside the locking 1216 * protection here, but there are probably other 1217 * places that this also happens. We must rethink 1218 * this. 1219 */ 1220 error = (*so->so_proto->pr_usrreqs->pru_send)(so, 1221 (flags & MSG_OOB) ? PRUS_OOB : 1222 /* 1223 * If the user set MSG_EOF, the protocol understands 1224 * this flag and nothing left to send then use 1225 * PRU_SEND_EOF instead of PRU_SEND. 1226 */ 1227 ((flags & MSG_EOF) && 1228 (so->so_proto->pr_flags & PR_IMPLOPCL) && 1229 (resid <= 0)) ? 1230 PRUS_EOF : 1231 /* If there is more to send set PRUS_MORETOCOME. */ 1232 (resid > 0 && space > 0) ? PRUS_MORETOCOME : 0, 1233 top, addr, control, td); 1234 if (dontroute) { 1235 SOCK_LOCK(so); 1236 so->so_options &= ~SO_DONTROUTE; 1237 SOCK_UNLOCK(so); 1238 } 1239 clen = 0; 1240 control = NULL; 1241 top = NULL; 1242 if (error) { 1243 SOCKBUF_LOCK(&so->so_snd); 1244 goto release; 1245 } 1246 } while (resid && space > 0); 1247 SOCKBUF_LOCK(&so->so_snd); 1248 } while (resid); 1249 1250 release: 1251 SOCKBUF_LOCK_ASSERT(&so->so_snd); 1252 sbunlock(&so->so_snd); 1253 out_locked: 1254 SOCKBUF_LOCK_ASSERT(&so->so_snd); 1255 SOCKBUF_UNLOCK(&so->so_snd); 1256 out: 1257 if (top != NULL) 1258 m_freem(top); 1259 if (control != NULL) 1260 m_freem(control); 1261 return (error); 1262 } 1263 #undef snderr 1264 1265 int 1266 sosend(so, addr, uio, top, control, flags, td) 1267 struct socket *so; 1268 struct sockaddr *addr; 1269 struct uio *uio; 1270 struct mbuf *top; 1271 struct mbuf *control; 1272 int flags; 1273 struct thread *td; 1274 { 1275 1276 /* XXXRW: Temporary debugging. */ 1277 KASSERT(so->so_proto->pr_usrreqs->pru_sosend != sosend, 1278 ("sosend: protocol calls sosend")); 1279 1280 return (so->so_proto->pr_usrreqs->pru_sosend(so, addr, uio, top, 1281 control, flags, td)); 1282 } 1283 1284 /* 1285 * The part of soreceive() that implements reading non-inline out-of-band 1286 * data from a socket. For more complete comments, see soreceive(), from 1287 * which this code originated. 1288 * 1289 * Note that soreceive_rcvoob(), unlike the remainder of soreceive(), is 1290 * unable to return an mbuf chain to the caller. 1291 */ 1292 static int 1293 soreceive_rcvoob(so, uio, flags) 1294 struct socket *so; 1295 struct uio *uio; 1296 int flags; 1297 { 1298 struct protosw *pr = so->so_proto; 1299 struct mbuf *m; 1300 int error; 1301 1302 KASSERT(flags & MSG_OOB, ("soreceive_rcvoob: (flags & MSG_OOB) == 0")); 1303 1304 m = m_get(M_TRYWAIT, MT_DATA); 1305 if (m == NULL) 1306 return (ENOBUFS); 1307 error = (*pr->pr_usrreqs->pru_rcvoob)(so, m, flags & MSG_PEEK); 1308 if (error) 1309 goto bad; 1310 do { 1311 #ifdef ZERO_COPY_SOCKETS 1312 if (so_zero_copy_receive) { 1313 int disposable; 1314 1315 if ((m->m_flags & M_EXT) 1316 && (m->m_ext.ext_type == EXT_DISPOSABLE)) 1317 disposable = 1; 1318 else 1319 disposable = 0; 1320 1321 error = uiomoveco(mtod(m, void *), 1322 min(uio->uio_resid, m->m_len), 1323 uio, disposable); 1324 } else 1325 #endif /* ZERO_COPY_SOCKETS */ 1326 error = uiomove(mtod(m, void *), 1327 (int) min(uio->uio_resid, m->m_len), uio); 1328 m = m_free(m); 1329 } while (uio->uio_resid && error == 0 && m); 1330 bad: 1331 if (m != NULL) 1332 m_freem(m); 1333 return (error); 1334 } 1335 1336 /* 1337 * Following replacement or removal of the first mbuf on the first mbuf chain 1338 * of a socket buffer, push necessary state changes back into the socket 1339 * buffer so that other consumers see the values consistently. 'nextrecord' 1340 * is the callers locally stored value of the original value of 1341 * sb->sb_mb->m_nextpkt which must be restored when the lead mbuf changes. 1342 * NOTE: 'nextrecord' may be NULL. 1343 */ 1344 static __inline void 1345 sockbuf_pushsync(struct sockbuf *sb, struct mbuf *nextrecord) 1346 { 1347 1348 SOCKBUF_LOCK_ASSERT(sb); 1349 /* 1350 * First, update for the new value of nextrecord. If necessary, make 1351 * it the first record. 1352 */ 1353 if (sb->sb_mb != NULL) 1354 sb->sb_mb->m_nextpkt = nextrecord; 1355 else 1356 sb->sb_mb = nextrecord; 1357 1358 /* 1359 * Now update any dependent socket buffer fields to reflect the new 1360 * state. This is an expanded inline of SB_EMPTY_FIXUP(), with the 1361 * addition of a second clause that takes care of the case where 1362 * sb_mb has been updated, but remains the last record. 1363 */ 1364 if (sb->sb_mb == NULL) { 1365 sb->sb_mbtail = NULL; 1366 sb->sb_lastrecord = NULL; 1367 } else if (sb->sb_mb->m_nextpkt == NULL) 1368 sb->sb_lastrecord = sb->sb_mb; 1369 } 1370 1371 1372 /* 1373 * Implement receive operations on a socket. We depend on the way that 1374 * records are added to the sockbuf by sbappend. In particular, each record 1375 * (mbufs linked through m_next) must begin with an address if the protocol 1376 * so specifies, followed by an optional mbuf or mbufs containing ancillary 1377 * data, and then zero or more mbufs of data. In order to allow parallelism 1378 * between network receive and copying to user space, as well as avoid 1379 * sleeping with a mutex held, we release the socket buffer mutex during the 1380 * user space copy. Although the sockbuf is locked, new data may still be 1381 * appended, and thus we must maintain consistency of the sockbuf during that 1382 * time. 1383 * 1384 * The caller may receive the data as a single mbuf chain by supplying an 1385 * mbuf **mp0 for use in returning the chain. The uio is then used only for 1386 * the count in uio_resid. 1387 */ 1388 int 1389 soreceive_generic(so, psa, uio, mp0, controlp, flagsp) 1390 struct socket *so; 1391 struct sockaddr **psa; 1392 struct uio *uio; 1393 struct mbuf **mp0; 1394 struct mbuf **controlp; 1395 int *flagsp; 1396 { 1397 struct mbuf *m, **mp; 1398 int flags, len, error, offset; 1399 struct protosw *pr = so->so_proto; 1400 struct mbuf *nextrecord; 1401 int moff, type = 0; 1402 int orig_resid = uio->uio_resid; 1403 1404 mp = mp0; 1405 if (psa != NULL) 1406 *psa = NULL; 1407 if (controlp != NULL) 1408 *controlp = NULL; 1409 if (flagsp != NULL) 1410 flags = *flagsp &~ MSG_EOR; 1411 else 1412 flags = 0; 1413 if (flags & MSG_OOB) 1414 return (soreceive_rcvoob(so, uio, flags)); 1415 if (mp != NULL) 1416 *mp = NULL; 1417 if ((pr->pr_flags & PR_WANTRCVD) && (so->so_state & SS_ISCONFIRMING) 1418 && uio->uio_resid) 1419 (*pr->pr_usrreqs->pru_rcvd)(so, 0); 1420 1421 SOCKBUF_LOCK(&so->so_rcv); 1422 restart: 1423 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 1424 error = sblock(&so->so_rcv, SBLOCKWAIT(flags)); 1425 if (error) 1426 goto out; 1427 1428 m = so->so_rcv.sb_mb; 1429 /* 1430 * If we have less data than requested, block awaiting more (subject 1431 * to any timeout) if: 1432 * 1. the current count is less than the low water mark, or 1433 * 2. MSG_WAITALL is set, and it is possible to do the entire 1434 * receive operation at once if we block (resid <= hiwat). 1435 * 3. MSG_DONTWAIT is not set 1436 * If MSG_WAITALL is set but resid is larger than the receive buffer, 1437 * we have to do the receive in sections, and thus risk returning a 1438 * short count if a timeout or signal occurs after we start. 1439 */ 1440 if (m == NULL || (((flags & MSG_DONTWAIT) == 0 && 1441 so->so_rcv.sb_cc < uio->uio_resid) && 1442 (so->so_rcv.sb_cc < so->so_rcv.sb_lowat || 1443 ((flags & MSG_WAITALL) && uio->uio_resid <= so->so_rcv.sb_hiwat)) && 1444 m->m_nextpkt == NULL && (pr->pr_flags & PR_ATOMIC) == 0)) { 1445 KASSERT(m != NULL || !so->so_rcv.sb_cc, 1446 ("receive: m == %p so->so_rcv.sb_cc == %u", 1447 m, so->so_rcv.sb_cc)); 1448 if (so->so_error) { 1449 if (m != NULL) 1450 goto dontblock; 1451 error = so->so_error; 1452 if ((flags & MSG_PEEK) == 0) 1453 so->so_error = 0; 1454 goto release; 1455 } 1456 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 1457 if (so->so_rcv.sb_state & SBS_CANTRCVMORE) { 1458 if (m) 1459 goto dontblock; 1460 else 1461 goto release; 1462 } 1463 for (; m != NULL; m = m->m_next) 1464 if (m->m_type == MT_OOBDATA || (m->m_flags & M_EOR)) { 1465 m = so->so_rcv.sb_mb; 1466 goto dontblock; 1467 } 1468 if ((so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING)) == 0 && 1469 (so->so_proto->pr_flags & PR_CONNREQUIRED)) { 1470 error = ENOTCONN; 1471 goto release; 1472 } 1473 if (uio->uio_resid == 0) 1474 goto release; 1475 if ((so->so_state & SS_NBIO) || 1476 (flags & (MSG_DONTWAIT|MSG_NBIO))) { 1477 error = EWOULDBLOCK; 1478 goto release; 1479 } 1480 SBLASTRECORDCHK(&so->so_rcv); 1481 SBLASTMBUFCHK(&so->so_rcv); 1482 sbunlock(&so->so_rcv); 1483 error = sbwait(&so->so_rcv); 1484 if (error) 1485 goto out; 1486 goto restart; 1487 } 1488 dontblock: 1489 /* 1490 * From this point onward, we maintain 'nextrecord' as a cache of the 1491 * pointer to the next record in the socket buffer. We must keep the 1492 * various socket buffer pointers and local stack versions of the 1493 * pointers in sync, pushing out modifications before dropping the 1494 * socket buffer mutex, and re-reading them when picking it up. 1495 * 1496 * Otherwise, we will race with the network stack appending new data 1497 * or records onto the socket buffer by using inconsistent/stale 1498 * versions of the field, possibly resulting in socket buffer 1499 * corruption. 1500 * 1501 * By holding the high-level sblock(), we prevent simultaneous 1502 * readers from pulling off the front of the socket buffer. 1503 */ 1504 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 1505 if (uio->uio_td) 1506 uio->uio_td->td_proc->p_stats->p_ru.ru_msgrcv++; 1507 KASSERT(m == so->so_rcv.sb_mb, ("soreceive: m != so->so_rcv.sb_mb")); 1508 SBLASTRECORDCHK(&so->so_rcv); 1509 SBLASTMBUFCHK(&so->so_rcv); 1510 nextrecord = m->m_nextpkt; 1511 if (pr->pr_flags & PR_ADDR) { 1512 KASSERT(m->m_type == MT_SONAME, 1513 ("m->m_type == %d", m->m_type)); 1514 orig_resid = 0; 1515 if (psa != NULL) 1516 *psa = sodupsockaddr(mtod(m, struct sockaddr *), 1517 M_NOWAIT); 1518 if (flags & MSG_PEEK) { 1519 m = m->m_next; 1520 } else { 1521 sbfree(&so->so_rcv, m); 1522 so->so_rcv.sb_mb = m_free(m); 1523 m = so->so_rcv.sb_mb; 1524 sockbuf_pushsync(&so->so_rcv, nextrecord); 1525 } 1526 } 1527 1528 /* 1529 * Process one or more MT_CONTROL mbufs present before any data mbufs 1530 * in the first mbuf chain on the socket buffer. If MSG_PEEK, we 1531 * just copy the data; if !MSG_PEEK, we call into the protocol to 1532 * perform externalization (or freeing if controlp == NULL). 1533 */ 1534 if (m != NULL && m->m_type == MT_CONTROL) { 1535 struct mbuf *cm = NULL, *cmn; 1536 struct mbuf **cme = &cm; 1537 1538 do { 1539 if (flags & MSG_PEEK) { 1540 if (controlp != NULL) { 1541 *controlp = m_copy(m, 0, m->m_len); 1542 controlp = &(*controlp)->m_next; 1543 } 1544 m = m->m_next; 1545 } else { 1546 sbfree(&so->so_rcv, m); 1547 so->so_rcv.sb_mb = m->m_next; 1548 m->m_next = NULL; 1549 *cme = m; 1550 cme = &(*cme)->m_next; 1551 m = so->so_rcv.sb_mb; 1552 } 1553 } while (m != NULL && m->m_type == MT_CONTROL); 1554 if ((flags & MSG_PEEK) == 0) 1555 sockbuf_pushsync(&so->so_rcv, nextrecord); 1556 while (cm != NULL) { 1557 cmn = cm->m_next; 1558 cm->m_next = NULL; 1559 if (pr->pr_domain->dom_externalize != NULL) { 1560 SOCKBUF_UNLOCK(&so->so_rcv); 1561 error = (*pr->pr_domain->dom_externalize) 1562 (cm, controlp); 1563 SOCKBUF_LOCK(&so->so_rcv); 1564 } else if (controlp != NULL) 1565 *controlp = cm; 1566 else 1567 m_freem(cm); 1568 if (controlp != NULL) { 1569 orig_resid = 0; 1570 while (*controlp != NULL) 1571 controlp = &(*controlp)->m_next; 1572 } 1573 cm = cmn; 1574 } 1575 if (so->so_rcv.sb_mb) 1576 nextrecord = so->so_rcv.sb_mb->m_nextpkt; 1577 else 1578 nextrecord = NULL; 1579 orig_resid = 0; 1580 } 1581 if (m != NULL) { 1582 if ((flags & MSG_PEEK) == 0) { 1583 KASSERT(m->m_nextpkt == nextrecord, 1584 ("soreceive: post-control, nextrecord !sync")); 1585 if (nextrecord == NULL) { 1586 KASSERT(so->so_rcv.sb_mb == m, 1587 ("soreceive: post-control, sb_mb!=m")); 1588 KASSERT(so->so_rcv.sb_lastrecord == m, 1589 ("soreceive: post-control, lastrecord!=m")); 1590 } 1591 } 1592 type = m->m_type; 1593 if (type == MT_OOBDATA) 1594 flags |= MSG_OOB; 1595 } else { 1596 if ((flags & MSG_PEEK) == 0) { 1597 KASSERT(so->so_rcv.sb_mb == nextrecord, 1598 ("soreceive: sb_mb != nextrecord")); 1599 if (so->so_rcv.sb_mb == NULL) { 1600 KASSERT(so->so_rcv.sb_lastrecord == NULL, 1601 ("soreceive: sb_lastercord != NULL")); 1602 } 1603 } 1604 } 1605 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 1606 SBLASTRECORDCHK(&so->so_rcv); 1607 SBLASTMBUFCHK(&so->so_rcv); 1608 1609 /* 1610 * Now continue to read any data mbufs off of the head of the socket 1611 * buffer until the read request is satisfied. Note that 'type' is 1612 * used to store the type of any mbuf reads that have happened so far 1613 * such that soreceive() can stop reading if the type changes, which 1614 * causes soreceive() to return only one of regular data and inline 1615 * out-of-band data in a single socket receive operation. 1616 */ 1617 moff = 0; 1618 offset = 0; 1619 while (m != NULL && uio->uio_resid > 0 && error == 0) { 1620 /* 1621 * If the type of mbuf has changed since the last mbuf 1622 * examined ('type'), end the receive operation. 1623 */ 1624 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 1625 if (m->m_type == MT_OOBDATA) { 1626 if (type != MT_OOBDATA) 1627 break; 1628 } else if (type == MT_OOBDATA) 1629 break; 1630 else 1631 KASSERT(m->m_type == MT_DATA, 1632 ("m->m_type == %d", m->m_type)); 1633 so->so_rcv.sb_state &= ~SBS_RCVATMARK; 1634 len = uio->uio_resid; 1635 if (so->so_oobmark && len > so->so_oobmark - offset) 1636 len = so->so_oobmark - offset; 1637 if (len > m->m_len - moff) 1638 len = m->m_len - moff; 1639 /* 1640 * If mp is set, just pass back the mbufs. Otherwise copy 1641 * them out via the uio, then free. Sockbuf must be 1642 * consistent here (points to current mbuf, it points to next 1643 * record) when we drop priority; we must note any additions 1644 * to the sockbuf when we block interrupts again. 1645 */ 1646 if (mp == NULL) { 1647 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 1648 SBLASTRECORDCHK(&so->so_rcv); 1649 SBLASTMBUFCHK(&so->so_rcv); 1650 SOCKBUF_UNLOCK(&so->so_rcv); 1651 #ifdef ZERO_COPY_SOCKETS 1652 if (so_zero_copy_receive) { 1653 int disposable; 1654 1655 if ((m->m_flags & M_EXT) 1656 && (m->m_ext.ext_type == EXT_DISPOSABLE)) 1657 disposable = 1; 1658 else 1659 disposable = 0; 1660 1661 error = uiomoveco(mtod(m, char *) + moff, 1662 (int)len, uio, 1663 disposable); 1664 } else 1665 #endif /* ZERO_COPY_SOCKETS */ 1666 error = uiomove(mtod(m, char *) + moff, (int)len, uio); 1667 SOCKBUF_LOCK(&so->so_rcv); 1668 if (error) 1669 goto release; 1670 } else 1671 uio->uio_resid -= len; 1672 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 1673 if (len == m->m_len - moff) { 1674 if (m->m_flags & M_EOR) 1675 flags |= MSG_EOR; 1676 if (flags & MSG_PEEK) { 1677 m = m->m_next; 1678 moff = 0; 1679 } else { 1680 nextrecord = m->m_nextpkt; 1681 sbfree(&so->so_rcv, m); 1682 if (mp != NULL) { 1683 *mp = m; 1684 mp = &m->m_next; 1685 so->so_rcv.sb_mb = m = m->m_next; 1686 *mp = NULL; 1687 } else { 1688 so->so_rcv.sb_mb = m_free(m); 1689 m = so->so_rcv.sb_mb; 1690 } 1691 sockbuf_pushsync(&so->so_rcv, nextrecord); 1692 SBLASTRECORDCHK(&so->so_rcv); 1693 SBLASTMBUFCHK(&so->so_rcv); 1694 } 1695 } else { 1696 if (flags & MSG_PEEK) 1697 moff += len; 1698 else { 1699 if (mp != NULL) { 1700 int copy_flag; 1701 1702 if (flags & MSG_DONTWAIT) 1703 copy_flag = M_DONTWAIT; 1704 else 1705 copy_flag = M_TRYWAIT; 1706 if (copy_flag == M_TRYWAIT) 1707 SOCKBUF_UNLOCK(&so->so_rcv); 1708 *mp = m_copym(m, 0, len, copy_flag); 1709 if (copy_flag == M_TRYWAIT) 1710 SOCKBUF_LOCK(&so->so_rcv); 1711 if (*mp == NULL) { 1712 /* 1713 * m_copym() couldn't 1714 * allocate an mbuf. Adjust 1715 * uio_resid back (it was 1716 * adjusted down by len 1717 * bytes, which we didn't end 1718 * up "copying" over). 1719 */ 1720 uio->uio_resid += len; 1721 break; 1722 } 1723 } 1724 m->m_data += len; 1725 m->m_len -= len; 1726 so->so_rcv.sb_cc -= len; 1727 } 1728 } 1729 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 1730 if (so->so_oobmark) { 1731 if ((flags & MSG_PEEK) == 0) { 1732 so->so_oobmark -= len; 1733 if (so->so_oobmark == 0) { 1734 so->so_rcv.sb_state |= SBS_RCVATMARK; 1735 break; 1736 } 1737 } else { 1738 offset += len; 1739 if (offset == so->so_oobmark) 1740 break; 1741 } 1742 } 1743 if (flags & MSG_EOR) 1744 break; 1745 /* 1746 * If the MSG_WAITALL flag is set (for non-atomic socket), we 1747 * must not quit until "uio->uio_resid == 0" or an error 1748 * termination. If a signal/timeout occurs, return with a 1749 * short count but without error. Keep sockbuf locked 1750 * against other readers. 1751 */ 1752 while (flags & MSG_WAITALL && m == NULL && uio->uio_resid > 0 && 1753 !sosendallatonce(so) && nextrecord == NULL) { 1754 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 1755 if (so->so_error || so->so_rcv.sb_state & SBS_CANTRCVMORE) 1756 break; 1757 /* 1758 * Notify the protocol that some data has been 1759 * drained before blocking. 1760 */ 1761 if (pr->pr_flags & PR_WANTRCVD) { 1762 SOCKBUF_UNLOCK(&so->so_rcv); 1763 (*pr->pr_usrreqs->pru_rcvd)(so, flags); 1764 SOCKBUF_LOCK(&so->so_rcv); 1765 } 1766 SBLASTRECORDCHK(&so->so_rcv); 1767 SBLASTMBUFCHK(&so->so_rcv); 1768 error = sbwait(&so->so_rcv); 1769 if (error) 1770 goto release; 1771 m = so->so_rcv.sb_mb; 1772 if (m != NULL) 1773 nextrecord = m->m_nextpkt; 1774 } 1775 } 1776 1777 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 1778 if (m != NULL && pr->pr_flags & PR_ATOMIC) { 1779 flags |= MSG_TRUNC; 1780 if ((flags & MSG_PEEK) == 0) 1781 (void) sbdroprecord_locked(&so->so_rcv); 1782 } 1783 if ((flags & MSG_PEEK) == 0) { 1784 if (m == NULL) { 1785 /* 1786 * First part is an inline SB_EMPTY_FIXUP(). Second 1787 * part makes sure sb_lastrecord is up-to-date if 1788 * there is still data in the socket buffer. 1789 */ 1790 so->so_rcv.sb_mb = nextrecord; 1791 if (so->so_rcv.sb_mb == NULL) { 1792 so->so_rcv.sb_mbtail = NULL; 1793 so->so_rcv.sb_lastrecord = NULL; 1794 } else if (nextrecord->m_nextpkt == NULL) 1795 so->so_rcv.sb_lastrecord = nextrecord; 1796 } 1797 SBLASTRECORDCHK(&so->so_rcv); 1798 SBLASTMBUFCHK(&so->so_rcv); 1799 /* 1800 * If soreceive() is being done from the socket callback, 1801 * then don't need to generate ACK to peer to update window, 1802 * since ACK will be generated on return to TCP. 1803 */ 1804 if (!(flags & MSG_SOCALLBCK) && 1805 (pr->pr_flags & PR_WANTRCVD)) { 1806 SOCKBUF_UNLOCK(&so->so_rcv); 1807 (*pr->pr_usrreqs->pru_rcvd)(so, flags); 1808 SOCKBUF_LOCK(&so->so_rcv); 1809 } 1810 } 1811 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 1812 if (orig_resid == uio->uio_resid && orig_resid && 1813 (flags & MSG_EOR) == 0 && (so->so_rcv.sb_state & SBS_CANTRCVMORE) == 0) { 1814 sbunlock(&so->so_rcv); 1815 goto restart; 1816 } 1817 1818 if (flagsp != NULL) 1819 *flagsp |= flags; 1820 release: 1821 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 1822 sbunlock(&so->so_rcv); 1823 out: 1824 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 1825 SOCKBUF_UNLOCK(&so->so_rcv); 1826 return (error); 1827 } 1828 1829 int 1830 soreceive(so, psa, uio, mp0, controlp, flagsp) 1831 struct socket *so; 1832 struct sockaddr **psa; 1833 struct uio *uio; 1834 struct mbuf **mp0; 1835 struct mbuf **controlp; 1836 int *flagsp; 1837 { 1838 1839 /* XXXRW: Temporary debugging. */ 1840 KASSERT(so->so_proto->pr_usrreqs->pru_soreceive != soreceive, 1841 ("soreceive: protocol calls soreceive")); 1842 1843 return (so->so_proto->pr_usrreqs->pru_soreceive(so, psa, uio, mp0, 1844 controlp, flagsp)); 1845 } 1846 1847 int 1848 soshutdown(so, how) 1849 struct socket *so; 1850 int how; 1851 { 1852 struct protosw *pr = so->so_proto; 1853 1854 if (!(how == SHUT_RD || how == SHUT_WR || how == SHUT_RDWR)) 1855 return (EINVAL); 1856 1857 if (how != SHUT_WR) 1858 sorflush(so); 1859 if (how != SHUT_RD) 1860 return ((*pr->pr_usrreqs->pru_shutdown)(so)); 1861 return (0); 1862 } 1863 1864 void 1865 sorflush(so) 1866 struct socket *so; 1867 { 1868 struct sockbuf *sb = &so->so_rcv; 1869 struct protosw *pr = so->so_proto; 1870 struct sockbuf asb; 1871 1872 /* 1873 * XXXRW: This is quite ugly. Previously, this code made a copy of 1874 * the socket buffer, then zero'd the original to clear the buffer 1875 * fields. However, with mutexes in the socket buffer, this causes 1876 * problems. We only clear the zeroable bits of the original; 1877 * however, we have to initialize and destroy the mutex in the copy 1878 * so that dom_dispose() and sbrelease() can lock t as needed. 1879 */ 1880 SOCKBUF_LOCK(sb); 1881 sb->sb_flags |= SB_NOINTR; 1882 (void) sblock(sb, M_WAITOK); 1883 /* 1884 * socantrcvmore_locked() drops the socket buffer mutex so that it 1885 * can safely perform wakeups. Re-acquire the mutex before 1886 * continuing. 1887 */ 1888 socantrcvmore_locked(so); 1889 SOCKBUF_LOCK(sb); 1890 sbunlock(sb); 1891 /* 1892 * Invalidate/clear most of the sockbuf structure, but leave selinfo 1893 * and mutex data unchanged. 1894 */ 1895 bzero(&asb, offsetof(struct sockbuf, sb_startzero)); 1896 bcopy(&sb->sb_startzero, &asb.sb_startzero, 1897 sizeof(*sb) - offsetof(struct sockbuf, sb_startzero)); 1898 bzero(&sb->sb_startzero, 1899 sizeof(*sb) - offsetof(struct sockbuf, sb_startzero)); 1900 SOCKBUF_UNLOCK(sb); 1901 1902 SOCKBUF_LOCK_INIT(&asb, "so_rcv"); 1903 if (pr->pr_flags & PR_RIGHTS && pr->pr_domain->dom_dispose != NULL) 1904 (*pr->pr_domain->dom_dispose)(asb.sb_mb); 1905 sbrelease(&asb, so); 1906 SOCKBUF_LOCK_DESTROY(&asb); 1907 } 1908 1909 /* 1910 * Perhaps this routine, and sooptcopyout(), below, ought to come in an 1911 * additional variant to handle the case where the option value needs to be 1912 * some kind of integer, but not a specific size. In addition to their use 1913 * here, these functions are also called by the protocol-level pr_ctloutput() 1914 * routines. 1915 */ 1916 int 1917 sooptcopyin(sopt, buf, len, minlen) 1918 struct sockopt *sopt; 1919 void *buf; 1920 size_t len; 1921 size_t minlen; 1922 { 1923 size_t valsize; 1924 1925 /* 1926 * If the user gives us more than we wanted, we ignore it, but if we 1927 * don't get the minimum length the caller wants, we return EINVAL. 1928 * On success, sopt->sopt_valsize is set to however much we actually 1929 * retrieved. 1930 */ 1931 if ((valsize = sopt->sopt_valsize) < minlen) 1932 return EINVAL; 1933 if (valsize > len) 1934 sopt->sopt_valsize = valsize = len; 1935 1936 if (sopt->sopt_td != NULL) 1937 return (copyin(sopt->sopt_val, buf, valsize)); 1938 1939 bcopy(sopt->sopt_val, buf, valsize); 1940 return (0); 1941 } 1942 1943 /* 1944 * Kernel version of setsockopt(2). 1945 * 1946 * XXX: optlen is size_t, not socklen_t 1947 */ 1948 int 1949 so_setsockopt(struct socket *so, int level, int optname, void *optval, 1950 size_t optlen) 1951 { 1952 struct sockopt sopt; 1953 1954 sopt.sopt_level = level; 1955 sopt.sopt_name = optname; 1956 sopt.sopt_dir = SOPT_SET; 1957 sopt.sopt_val = optval; 1958 sopt.sopt_valsize = optlen; 1959 sopt.sopt_td = NULL; 1960 return (sosetopt(so, &sopt)); 1961 } 1962 1963 int 1964 sosetopt(so, sopt) 1965 struct socket *so; 1966 struct sockopt *sopt; 1967 { 1968 int error, optval; 1969 struct linger l; 1970 struct timeval tv; 1971 u_long val; 1972 #ifdef MAC 1973 struct mac extmac; 1974 #endif 1975 1976 error = 0; 1977 if (sopt->sopt_level != SOL_SOCKET) { 1978 if (so->so_proto && so->so_proto->pr_ctloutput) 1979 return ((*so->so_proto->pr_ctloutput) 1980 (so, sopt)); 1981 error = ENOPROTOOPT; 1982 } else { 1983 switch (sopt->sopt_name) { 1984 #ifdef INET 1985 case SO_ACCEPTFILTER: 1986 error = do_setopt_accept_filter(so, sopt); 1987 if (error) 1988 goto bad; 1989 break; 1990 #endif 1991 case SO_LINGER: 1992 error = sooptcopyin(sopt, &l, sizeof l, sizeof l); 1993 if (error) 1994 goto bad; 1995 1996 SOCK_LOCK(so); 1997 so->so_linger = l.l_linger; 1998 if (l.l_onoff) 1999 so->so_options |= SO_LINGER; 2000 else 2001 so->so_options &= ~SO_LINGER; 2002 SOCK_UNLOCK(so); 2003 break; 2004 2005 case SO_DEBUG: 2006 case SO_KEEPALIVE: 2007 case SO_DONTROUTE: 2008 case SO_USELOOPBACK: 2009 case SO_BROADCAST: 2010 case SO_REUSEADDR: 2011 case SO_REUSEPORT: 2012 case SO_OOBINLINE: 2013 case SO_TIMESTAMP: 2014 case SO_BINTIME: 2015 case SO_NOSIGPIPE: 2016 error = sooptcopyin(sopt, &optval, sizeof optval, 2017 sizeof optval); 2018 if (error) 2019 goto bad; 2020 SOCK_LOCK(so); 2021 if (optval) 2022 so->so_options |= sopt->sopt_name; 2023 else 2024 so->so_options &= ~sopt->sopt_name; 2025 SOCK_UNLOCK(so); 2026 break; 2027 2028 case SO_SNDBUF: 2029 case SO_RCVBUF: 2030 case SO_SNDLOWAT: 2031 case SO_RCVLOWAT: 2032 error = sooptcopyin(sopt, &optval, sizeof optval, 2033 sizeof optval); 2034 if (error) 2035 goto bad; 2036 2037 /* 2038 * Values < 1 make no sense for any of these options, 2039 * so disallow them. 2040 */ 2041 if (optval < 1) { 2042 error = EINVAL; 2043 goto bad; 2044 } 2045 2046 switch (sopt->sopt_name) { 2047 case SO_SNDBUF: 2048 case SO_RCVBUF: 2049 if (sbreserve(sopt->sopt_name == SO_SNDBUF ? 2050 &so->so_snd : &so->so_rcv, (u_long)optval, 2051 so, curthread) == 0) { 2052 error = ENOBUFS; 2053 goto bad; 2054 } 2055 break; 2056 2057 /* 2058 * Make sure the low-water is never greater than the 2059 * high-water. 2060 */ 2061 case SO_SNDLOWAT: 2062 SOCKBUF_LOCK(&so->so_snd); 2063 so->so_snd.sb_lowat = 2064 (optval > so->so_snd.sb_hiwat) ? 2065 so->so_snd.sb_hiwat : optval; 2066 SOCKBUF_UNLOCK(&so->so_snd); 2067 break; 2068 case SO_RCVLOWAT: 2069 SOCKBUF_LOCK(&so->so_rcv); 2070 so->so_rcv.sb_lowat = 2071 (optval > so->so_rcv.sb_hiwat) ? 2072 so->so_rcv.sb_hiwat : optval; 2073 SOCKBUF_UNLOCK(&so->so_rcv); 2074 break; 2075 } 2076 break; 2077 2078 case SO_SNDTIMEO: 2079 case SO_RCVTIMEO: 2080 #ifdef COMPAT_IA32 2081 if (curthread->td_proc->p_sysent == &ia32_freebsd_sysvec) { 2082 struct timeval32 tv32; 2083 2084 error = sooptcopyin(sopt, &tv32, sizeof tv32, 2085 sizeof tv32); 2086 CP(tv32, tv, tv_sec); 2087 CP(tv32, tv, tv_usec); 2088 } else 2089 #endif 2090 error = sooptcopyin(sopt, &tv, sizeof tv, 2091 sizeof tv); 2092 if (error) 2093 goto bad; 2094 2095 /* assert(hz > 0); */ 2096 if (tv.tv_sec < 0 || tv.tv_sec > INT_MAX / hz || 2097 tv.tv_usec < 0 || tv.tv_usec >= 1000000) { 2098 error = EDOM; 2099 goto bad; 2100 } 2101 /* assert(tick > 0); */ 2102 /* assert(ULONG_MAX - INT_MAX >= 1000000); */ 2103 val = (u_long)(tv.tv_sec * hz) + tv.tv_usec / tick; 2104 if (val > INT_MAX) { 2105 error = EDOM; 2106 goto bad; 2107 } 2108 if (val == 0 && tv.tv_usec != 0) 2109 val = 1; 2110 2111 switch (sopt->sopt_name) { 2112 case SO_SNDTIMEO: 2113 so->so_snd.sb_timeo = val; 2114 break; 2115 case SO_RCVTIMEO: 2116 so->so_rcv.sb_timeo = val; 2117 break; 2118 } 2119 break; 2120 2121 case SO_LABEL: 2122 #ifdef MAC 2123 error = sooptcopyin(sopt, &extmac, sizeof extmac, 2124 sizeof extmac); 2125 if (error) 2126 goto bad; 2127 error = mac_setsockopt_label(sopt->sopt_td->td_ucred, 2128 so, &extmac); 2129 #else 2130 error = EOPNOTSUPP; 2131 #endif 2132 break; 2133 2134 default: 2135 error = ENOPROTOOPT; 2136 break; 2137 } 2138 if (error == 0 && so->so_proto != NULL && 2139 so->so_proto->pr_ctloutput != NULL) { 2140 (void) ((*so->so_proto->pr_ctloutput) 2141 (so, sopt)); 2142 } 2143 } 2144 bad: 2145 return (error); 2146 } 2147 2148 /* 2149 * Helper routine for getsockopt. 2150 */ 2151 int 2152 sooptcopyout(struct sockopt *sopt, const void *buf, size_t len) 2153 { 2154 int error; 2155 size_t valsize; 2156 2157 error = 0; 2158 2159 /* 2160 * Documented get behavior is that we always return a value, possibly 2161 * truncated to fit in the user's buffer. Traditional behavior is 2162 * that we always tell the user precisely how much we copied, rather 2163 * than something useful like the total amount we had available for 2164 * her. Note that this interface is not idempotent; the entire 2165 * answer must generated ahead of time. 2166 */ 2167 valsize = min(len, sopt->sopt_valsize); 2168 sopt->sopt_valsize = valsize; 2169 if (sopt->sopt_val != NULL) { 2170 if (sopt->sopt_td != NULL) 2171 error = copyout(buf, sopt->sopt_val, valsize); 2172 else 2173 bcopy(buf, sopt->sopt_val, valsize); 2174 } 2175 return (error); 2176 } 2177 2178 int 2179 sogetopt(so, sopt) 2180 struct socket *so; 2181 struct sockopt *sopt; 2182 { 2183 int error, optval; 2184 struct linger l; 2185 struct timeval tv; 2186 #ifdef MAC 2187 struct mac extmac; 2188 #endif 2189 2190 error = 0; 2191 if (sopt->sopt_level != SOL_SOCKET) { 2192 if (so->so_proto && so->so_proto->pr_ctloutput) { 2193 return ((*so->so_proto->pr_ctloutput) 2194 (so, sopt)); 2195 } else 2196 return (ENOPROTOOPT); 2197 } else { 2198 switch (sopt->sopt_name) { 2199 #ifdef INET 2200 case SO_ACCEPTFILTER: 2201 error = do_getopt_accept_filter(so, sopt); 2202 break; 2203 #endif 2204 case SO_LINGER: 2205 SOCK_LOCK(so); 2206 l.l_onoff = so->so_options & SO_LINGER; 2207 l.l_linger = so->so_linger; 2208 SOCK_UNLOCK(so); 2209 error = sooptcopyout(sopt, &l, sizeof l); 2210 break; 2211 2212 case SO_USELOOPBACK: 2213 case SO_DONTROUTE: 2214 case SO_DEBUG: 2215 case SO_KEEPALIVE: 2216 case SO_REUSEADDR: 2217 case SO_REUSEPORT: 2218 case SO_BROADCAST: 2219 case SO_OOBINLINE: 2220 case SO_ACCEPTCONN: 2221 case SO_TIMESTAMP: 2222 case SO_BINTIME: 2223 case SO_NOSIGPIPE: 2224 optval = so->so_options & sopt->sopt_name; 2225 integer: 2226 error = sooptcopyout(sopt, &optval, sizeof optval); 2227 break; 2228 2229 case SO_TYPE: 2230 optval = so->so_type; 2231 goto integer; 2232 2233 case SO_ERROR: 2234 SOCK_LOCK(so); 2235 optval = so->so_error; 2236 so->so_error = 0; 2237 SOCK_UNLOCK(so); 2238 goto integer; 2239 2240 case SO_SNDBUF: 2241 optval = so->so_snd.sb_hiwat; 2242 goto integer; 2243 2244 case SO_RCVBUF: 2245 optval = so->so_rcv.sb_hiwat; 2246 goto integer; 2247 2248 case SO_SNDLOWAT: 2249 optval = so->so_snd.sb_lowat; 2250 goto integer; 2251 2252 case SO_RCVLOWAT: 2253 optval = so->so_rcv.sb_lowat; 2254 goto integer; 2255 2256 case SO_SNDTIMEO: 2257 case SO_RCVTIMEO: 2258 optval = (sopt->sopt_name == SO_SNDTIMEO ? 2259 so->so_snd.sb_timeo : so->so_rcv.sb_timeo); 2260 2261 tv.tv_sec = optval / hz; 2262 tv.tv_usec = (optval % hz) * tick; 2263 #ifdef COMPAT_IA32 2264 if (curthread->td_proc->p_sysent == &ia32_freebsd_sysvec) { 2265 struct timeval32 tv32; 2266 2267 CP(tv, tv32, tv_sec); 2268 CP(tv, tv32, tv_usec); 2269 error = sooptcopyout(sopt, &tv32, sizeof tv32); 2270 } else 2271 #endif 2272 error = sooptcopyout(sopt, &tv, sizeof tv); 2273 break; 2274 2275 case SO_LABEL: 2276 #ifdef MAC 2277 error = sooptcopyin(sopt, &extmac, sizeof(extmac), 2278 sizeof(extmac)); 2279 if (error) 2280 return (error); 2281 error = mac_getsockopt_label(sopt->sopt_td->td_ucred, 2282 so, &extmac); 2283 if (error) 2284 return (error); 2285 error = sooptcopyout(sopt, &extmac, sizeof extmac); 2286 #else 2287 error = EOPNOTSUPP; 2288 #endif 2289 break; 2290 2291 case SO_PEERLABEL: 2292 #ifdef MAC 2293 error = sooptcopyin(sopt, &extmac, sizeof(extmac), 2294 sizeof(extmac)); 2295 if (error) 2296 return (error); 2297 error = mac_getsockopt_peerlabel( 2298 sopt->sopt_td->td_ucred, so, &extmac); 2299 if (error) 2300 return (error); 2301 error = sooptcopyout(sopt, &extmac, sizeof extmac); 2302 #else 2303 error = EOPNOTSUPP; 2304 #endif 2305 break; 2306 2307 case SO_LISTENQLIMIT: 2308 optval = so->so_qlimit; 2309 goto integer; 2310 2311 case SO_LISTENQLEN: 2312 optval = so->so_qlen; 2313 goto integer; 2314 2315 case SO_LISTENINCQLEN: 2316 optval = so->so_incqlen; 2317 goto integer; 2318 2319 default: 2320 error = ENOPROTOOPT; 2321 break; 2322 } 2323 return (error); 2324 } 2325 } 2326 2327 /* XXX; prepare mbuf for (__FreeBSD__ < 3) routines. */ 2328 int 2329 soopt_getm(struct sockopt *sopt, struct mbuf **mp) 2330 { 2331 struct mbuf *m, *m_prev; 2332 int sopt_size = sopt->sopt_valsize; 2333 2334 MGET(m, sopt->sopt_td ? M_TRYWAIT : M_DONTWAIT, MT_DATA); 2335 if (m == NULL) 2336 return ENOBUFS; 2337 if (sopt_size > MLEN) { 2338 MCLGET(m, sopt->sopt_td ? M_TRYWAIT : M_DONTWAIT); 2339 if ((m->m_flags & M_EXT) == 0) { 2340 m_free(m); 2341 return ENOBUFS; 2342 } 2343 m->m_len = min(MCLBYTES, sopt_size); 2344 } else { 2345 m->m_len = min(MLEN, sopt_size); 2346 } 2347 sopt_size -= m->m_len; 2348 *mp = m; 2349 m_prev = m; 2350 2351 while (sopt_size) { 2352 MGET(m, sopt->sopt_td ? M_TRYWAIT : M_DONTWAIT, MT_DATA); 2353 if (m == NULL) { 2354 m_freem(*mp); 2355 return ENOBUFS; 2356 } 2357 if (sopt_size > MLEN) { 2358 MCLGET(m, sopt->sopt_td != NULL ? M_TRYWAIT : 2359 M_DONTWAIT); 2360 if ((m->m_flags & M_EXT) == 0) { 2361 m_freem(m); 2362 m_freem(*mp); 2363 return ENOBUFS; 2364 } 2365 m->m_len = min(MCLBYTES, sopt_size); 2366 } else { 2367 m->m_len = min(MLEN, sopt_size); 2368 } 2369 sopt_size -= m->m_len; 2370 m_prev->m_next = m; 2371 m_prev = m; 2372 } 2373 return (0); 2374 } 2375 2376 /* XXX; copyin sopt data into mbuf chain for (__FreeBSD__ < 3) routines. */ 2377 int 2378 soopt_mcopyin(struct sockopt *sopt, struct mbuf *m) 2379 { 2380 struct mbuf *m0 = m; 2381 2382 if (sopt->sopt_val == NULL) 2383 return (0); 2384 while (m != NULL && sopt->sopt_valsize >= m->m_len) { 2385 if (sopt->sopt_td != NULL) { 2386 int error; 2387 2388 error = copyin(sopt->sopt_val, mtod(m, char *), 2389 m->m_len); 2390 if (error != 0) { 2391 m_freem(m0); 2392 return(error); 2393 } 2394 } else 2395 bcopy(sopt->sopt_val, mtod(m, char *), m->m_len); 2396 sopt->sopt_valsize -= m->m_len; 2397 sopt->sopt_val = (char *)sopt->sopt_val + m->m_len; 2398 m = m->m_next; 2399 } 2400 if (m != NULL) /* should be allocated enoughly at ip6_sooptmcopyin() */ 2401 panic("ip6_sooptmcopyin"); 2402 return (0); 2403 } 2404 2405 /* XXX; copyout mbuf chain data into soopt for (__FreeBSD__ < 3) routines. */ 2406 int 2407 soopt_mcopyout(struct sockopt *sopt, struct mbuf *m) 2408 { 2409 struct mbuf *m0 = m; 2410 size_t valsize = 0; 2411 2412 if (sopt->sopt_val == NULL) 2413 return (0); 2414 while (m != NULL && sopt->sopt_valsize >= m->m_len) { 2415 if (sopt->sopt_td != NULL) { 2416 int error; 2417 2418 error = copyout(mtod(m, char *), sopt->sopt_val, 2419 m->m_len); 2420 if (error != 0) { 2421 m_freem(m0); 2422 return(error); 2423 } 2424 } else 2425 bcopy(mtod(m, char *), sopt->sopt_val, m->m_len); 2426 sopt->sopt_valsize -= m->m_len; 2427 sopt->sopt_val = (char *)sopt->sopt_val + m->m_len; 2428 valsize += m->m_len; 2429 m = m->m_next; 2430 } 2431 if (m != NULL) { 2432 /* enough soopt buffer should be given from user-land */ 2433 m_freem(m0); 2434 return(EINVAL); 2435 } 2436 sopt->sopt_valsize = valsize; 2437 return (0); 2438 } 2439 2440 /* 2441 * sohasoutofband(): protocol notifies socket layer of the arrival of new 2442 * out-of-band data, which will then notify socket consumers. 2443 */ 2444 void 2445 sohasoutofband(so) 2446 struct socket *so; 2447 { 2448 if (so->so_sigio != NULL) 2449 pgsigio(&so->so_sigio, SIGURG, 0); 2450 selwakeuppri(&so->so_rcv.sb_sel, PSOCK); 2451 } 2452 2453 int 2454 sopoll(struct socket *so, int events, struct ucred *active_cred, 2455 struct thread *td) 2456 { 2457 2458 /* XXXRW: Temporary debugging. */ 2459 KASSERT(so->so_proto->pr_usrreqs->pru_sopoll != sopoll, 2460 ("sopoll: protocol calls sopoll")); 2461 2462 return (so->so_proto->pr_usrreqs->pru_sopoll(so, events, active_cred, 2463 td)); 2464 } 2465 2466 int 2467 sopoll_generic(struct socket *so, int events, struct ucred *active_cred, 2468 struct thread *td) 2469 { 2470 int revents = 0; 2471 2472 SOCKBUF_LOCK(&so->so_snd); 2473 SOCKBUF_LOCK(&so->so_rcv); 2474 if (events & (POLLIN | POLLRDNORM)) 2475 if (soreadable(so)) 2476 revents |= events & (POLLIN | POLLRDNORM); 2477 2478 if (events & POLLINIGNEOF) 2479 if (so->so_rcv.sb_cc >= so->so_rcv.sb_lowat || 2480 !TAILQ_EMPTY(&so->so_comp) || so->so_error) 2481 revents |= POLLINIGNEOF; 2482 2483 if (events & (POLLOUT | POLLWRNORM)) 2484 if (sowriteable(so)) 2485 revents |= events & (POLLOUT | POLLWRNORM); 2486 2487 if (events & (POLLPRI | POLLRDBAND)) 2488 if (so->so_oobmark || (so->so_rcv.sb_state & SBS_RCVATMARK)) 2489 revents |= events & (POLLPRI | POLLRDBAND); 2490 2491 if (revents == 0) { 2492 if (events & 2493 (POLLIN | POLLINIGNEOF | POLLPRI | POLLRDNORM | 2494 POLLRDBAND)) { 2495 selrecord(td, &so->so_rcv.sb_sel); 2496 so->so_rcv.sb_flags |= SB_SEL; 2497 } 2498 2499 if (events & (POLLOUT | POLLWRNORM)) { 2500 selrecord(td, &so->so_snd.sb_sel); 2501 so->so_snd.sb_flags |= SB_SEL; 2502 } 2503 } 2504 2505 SOCKBUF_UNLOCK(&so->so_rcv); 2506 SOCKBUF_UNLOCK(&so->so_snd); 2507 return (revents); 2508 } 2509 2510 int 2511 soo_kqfilter(struct file *fp, struct knote *kn) 2512 { 2513 struct socket *so = kn->kn_fp->f_data; 2514 struct sockbuf *sb; 2515 2516 switch (kn->kn_filter) { 2517 case EVFILT_READ: 2518 if (so->so_options & SO_ACCEPTCONN) 2519 kn->kn_fop = &solisten_filtops; 2520 else 2521 kn->kn_fop = &soread_filtops; 2522 sb = &so->so_rcv; 2523 break; 2524 case EVFILT_WRITE: 2525 kn->kn_fop = &sowrite_filtops; 2526 sb = &so->so_snd; 2527 break; 2528 default: 2529 return (EINVAL); 2530 } 2531 2532 SOCKBUF_LOCK(sb); 2533 knlist_add(&sb->sb_sel.si_note, kn, 1); 2534 sb->sb_flags |= SB_KNOTE; 2535 SOCKBUF_UNLOCK(sb); 2536 return (0); 2537 } 2538 2539 static void 2540 filt_sordetach(struct knote *kn) 2541 { 2542 struct socket *so = kn->kn_fp->f_data; 2543 2544 SOCKBUF_LOCK(&so->so_rcv); 2545 knlist_remove(&so->so_rcv.sb_sel.si_note, kn, 1); 2546 if (knlist_empty(&so->so_rcv.sb_sel.si_note)) 2547 so->so_rcv.sb_flags &= ~SB_KNOTE; 2548 SOCKBUF_UNLOCK(&so->so_rcv); 2549 } 2550 2551 /*ARGSUSED*/ 2552 static int 2553 filt_soread(struct knote *kn, long hint) 2554 { 2555 struct socket *so; 2556 2557 so = kn->kn_fp->f_data; 2558 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 2559 2560 kn->kn_data = so->so_rcv.sb_cc - so->so_rcv.sb_ctl; 2561 if (so->so_rcv.sb_state & SBS_CANTRCVMORE) { 2562 kn->kn_flags |= EV_EOF; 2563 kn->kn_fflags = so->so_error; 2564 return (1); 2565 } else if (so->so_error) /* temporary udp error */ 2566 return (1); 2567 else if (kn->kn_sfflags & NOTE_LOWAT) 2568 return (kn->kn_data >= kn->kn_sdata); 2569 else 2570 return (so->so_rcv.sb_cc >= so->so_rcv.sb_lowat); 2571 } 2572 2573 static void 2574 filt_sowdetach(struct knote *kn) 2575 { 2576 struct socket *so = kn->kn_fp->f_data; 2577 2578 SOCKBUF_LOCK(&so->so_snd); 2579 knlist_remove(&so->so_snd.sb_sel.si_note, kn, 1); 2580 if (knlist_empty(&so->so_snd.sb_sel.si_note)) 2581 so->so_snd.sb_flags &= ~SB_KNOTE; 2582 SOCKBUF_UNLOCK(&so->so_snd); 2583 } 2584 2585 /*ARGSUSED*/ 2586 static int 2587 filt_sowrite(struct knote *kn, long hint) 2588 { 2589 struct socket *so; 2590 2591 so = kn->kn_fp->f_data; 2592 SOCKBUF_LOCK_ASSERT(&so->so_snd); 2593 kn->kn_data = sbspace(&so->so_snd); 2594 if (so->so_snd.sb_state & SBS_CANTSENDMORE) { 2595 kn->kn_flags |= EV_EOF; 2596 kn->kn_fflags = so->so_error; 2597 return (1); 2598 } else if (so->so_error) /* temporary udp error */ 2599 return (1); 2600 else if (((so->so_state & SS_ISCONNECTED) == 0) && 2601 (so->so_proto->pr_flags & PR_CONNREQUIRED)) 2602 return (0); 2603 else if (kn->kn_sfflags & NOTE_LOWAT) 2604 return (kn->kn_data >= kn->kn_sdata); 2605 else 2606 return (kn->kn_data >= so->so_snd.sb_lowat); 2607 } 2608 2609 /*ARGSUSED*/ 2610 static int 2611 filt_solisten(struct knote *kn, long hint) 2612 { 2613 struct socket *so = kn->kn_fp->f_data; 2614 2615 kn->kn_data = so->so_qlen; 2616 return (! TAILQ_EMPTY(&so->so_comp)); 2617 } 2618 2619 int 2620 socheckuid(struct socket *so, uid_t uid) 2621 { 2622 2623 if (so == NULL) 2624 return (EPERM); 2625 if (so->so_cred->cr_uid != uid) 2626 return (EPERM); 2627 return (0); 2628 } 2629 2630 static int 2631 somaxconn_sysctl(SYSCTL_HANDLER_ARGS) 2632 { 2633 int error; 2634 int val; 2635 2636 val = somaxconn; 2637 error = sysctl_handle_int(oidp, &val, sizeof(int), req); 2638 if (error || !req->newptr ) 2639 return (error); 2640 2641 if (val < 1 || val > USHRT_MAX) 2642 return (EINVAL); 2643 2644 somaxconn = val; 2645 return (0); 2646 } 2647