1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1982, 1986, 1988, 1990, 1993 5 * The Regents of the University of California. 6 * Copyright (c) 2004 The FreeBSD Foundation 7 * Copyright (c) 2004-2008 Robert N. M. Watson 8 * All rights reserved. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)uipc_socket.c 8.3 (Berkeley) 4/15/94 35 */ 36 37 /* 38 * Comments on the socket life cycle: 39 * 40 * soalloc() sets of socket layer state for a socket, called only by 41 * socreate() and sonewconn(). Socket layer private. 42 * 43 * sodealloc() tears down socket layer state for a socket, called only by 44 * sofree() and sonewconn(). Socket layer private. 45 * 46 * pru_attach() associates protocol layer state with an allocated socket; 47 * called only once, may fail, aborting socket allocation. This is called 48 * from socreate() and sonewconn(). Socket layer private. 49 * 50 * pru_detach() disassociates protocol layer state from an attached socket, 51 * and will be called exactly once for sockets in which pru_attach() has 52 * been successfully called. If pru_attach() returned an error, 53 * pru_detach() will not be called. Socket layer private. 54 * 55 * pru_abort() and pru_close() notify the protocol layer that the last 56 * consumer of a socket is starting to tear down the socket, and that the 57 * protocol should terminate the connection. Historically, pru_abort() also 58 * detached protocol state from the socket state, but this is no longer the 59 * case. 60 * 61 * socreate() creates a socket and attaches protocol state. This is a public 62 * interface that may be used by socket layer consumers to create new 63 * sockets. 64 * 65 * sonewconn() creates a socket and attaches protocol state. This is a 66 * public interface that may be used by protocols to create new sockets when 67 * a new connection is received and will be available for accept() on a 68 * listen socket. 69 * 70 * soclose() destroys a socket after possibly waiting for it to disconnect. 71 * This is a public interface that socket consumers should use to close and 72 * release a socket when done with it. 73 * 74 * soabort() destroys a socket without waiting for it to disconnect (used 75 * only for incoming connections that are already partially or fully 76 * connected). This is used internally by the socket layer when clearing 77 * listen socket queues (due to overflow or close on the listen socket), but 78 * is also a public interface protocols may use to abort connections in 79 * their incomplete listen queues should they no longer be required. Sockets 80 * placed in completed connection listen queues should not be aborted for 81 * reasons described in the comment above the soclose() implementation. This 82 * is not a general purpose close routine, and except in the specific 83 * circumstances described here, should not be used. 84 * 85 * sofree() will free a socket and its protocol state if all references on 86 * the socket have been released, and is the public interface to attempt to 87 * free a socket when a reference is removed. This is a socket layer private 88 * interface. 89 * 90 * NOTE: In addition to socreate() and soclose(), which provide a single 91 * socket reference to the consumer to be managed as required, there are two 92 * calls to explicitly manage socket references, soref(), and sorele(). 93 * Currently, these are generally required only when transitioning a socket 94 * from a listen queue to a file descriptor, in order to prevent garbage 95 * collection of the socket at an untimely moment. For a number of reasons, 96 * these interfaces are not preferred, and should be avoided. 97 * 98 * NOTE: With regard to VNETs the general rule is that callers do not set 99 * curvnet. Exceptions to this rule include soabort(), sodisconnect(), 100 * sofree() (and with that sorele(), sotryfree()), as well as sonewconn() 101 * and sorflush(), which are usually called from a pre-set VNET context. 102 * sopoll() currently does not need a VNET context to be set. 103 */ 104 105 #include <sys/cdefs.h> 106 __FBSDID("$FreeBSD$"); 107 108 #include "opt_inet.h" 109 #include "opt_inet6.h" 110 #include "opt_kern_tls.h" 111 #include "opt_sctp.h" 112 113 #include <sys/param.h> 114 #include <sys/systm.h> 115 #include <sys/capsicum.h> 116 #include <sys/fcntl.h> 117 #include <sys/limits.h> 118 #include <sys/lock.h> 119 #include <sys/mac.h> 120 #include <sys/malloc.h> 121 #include <sys/mbuf.h> 122 #include <sys/mutex.h> 123 #include <sys/domain.h> 124 #include <sys/file.h> /* for struct knote */ 125 #include <sys/hhook.h> 126 #include <sys/kernel.h> 127 #include <sys/khelp.h> 128 #include <sys/ktls.h> 129 #include <sys/event.h> 130 #include <sys/eventhandler.h> 131 #include <sys/poll.h> 132 #include <sys/proc.h> 133 #include <sys/protosw.h> 134 #include <sys/sbuf.h> 135 #include <sys/socket.h> 136 #include <sys/socketvar.h> 137 #include <sys/resourcevar.h> 138 #include <net/route.h> 139 #include <sys/signalvar.h> 140 #include <sys/stat.h> 141 #include <sys/sx.h> 142 #include <sys/sysctl.h> 143 #include <sys/taskqueue.h> 144 #include <sys/uio.h> 145 #include <sys/un.h> 146 #include <sys/unpcb.h> 147 #include <sys/jail.h> 148 #include <sys/syslog.h> 149 #include <netinet/in.h> 150 #include <netinet/in_pcb.h> 151 #include <netinet/tcp.h> 152 153 #include <net/vnet.h> 154 155 #include <security/mac/mac_framework.h> 156 157 #include <vm/uma.h> 158 159 #ifdef COMPAT_FREEBSD32 160 #include <sys/mount.h> 161 #include <sys/sysent.h> 162 #include <compat/freebsd32/freebsd32.h> 163 #endif 164 165 static int soreceive_rcvoob(struct socket *so, struct uio *uio, 166 int flags); 167 static void so_rdknl_lock(void *); 168 static void so_rdknl_unlock(void *); 169 static void so_rdknl_assert_lock(void *, int); 170 static void so_wrknl_lock(void *); 171 static void so_wrknl_unlock(void *); 172 static void so_wrknl_assert_lock(void *, int); 173 174 static void filt_sordetach(struct knote *kn); 175 static int filt_soread(struct knote *kn, long hint); 176 static void filt_sowdetach(struct knote *kn); 177 static int filt_sowrite(struct knote *kn, long hint); 178 static int filt_soempty(struct knote *kn, long hint); 179 static int inline hhook_run_socket(struct socket *so, void *hctx, int32_t h_id); 180 fo_kqfilter_t soo_kqfilter; 181 182 static struct filterops soread_filtops = { 183 .f_isfd = 1, 184 .f_detach = filt_sordetach, 185 .f_event = filt_soread, 186 }; 187 static struct filterops sowrite_filtops = { 188 .f_isfd = 1, 189 .f_detach = filt_sowdetach, 190 .f_event = filt_sowrite, 191 }; 192 static struct filterops soempty_filtops = { 193 .f_isfd = 1, 194 .f_detach = filt_sowdetach, 195 .f_event = filt_soempty, 196 }; 197 198 so_gen_t so_gencnt; /* generation count for sockets */ 199 200 MALLOC_DEFINE(M_SONAME, "soname", "socket name"); 201 MALLOC_DEFINE(M_PCB, "pcb", "protocol control block"); 202 203 #define VNET_SO_ASSERT(so) \ 204 VNET_ASSERT(curvnet != NULL, \ 205 ("%s:%d curvnet is NULL, so=%p", __func__, __LINE__, (so))); 206 207 VNET_DEFINE(struct hhook_head *, socket_hhh[HHOOK_SOCKET_LAST + 1]); 208 #define V_socket_hhh VNET(socket_hhh) 209 210 /* 211 * Limit on the number of connections in the listen queue waiting 212 * for accept(2). 213 * NB: The original sysctl somaxconn is still available but hidden 214 * to prevent confusion about the actual purpose of this number. 215 */ 216 static u_int somaxconn = SOMAXCONN; 217 218 static int 219 sysctl_somaxconn(SYSCTL_HANDLER_ARGS) 220 { 221 int error; 222 int val; 223 224 val = somaxconn; 225 error = sysctl_handle_int(oidp, &val, 0, req); 226 if (error || !req->newptr ) 227 return (error); 228 229 /* 230 * The purpose of the UINT_MAX / 3 limit, is so that the formula 231 * 3 * so_qlimit / 2 232 * below, will not overflow. 233 */ 234 235 if (val < 1 || val > UINT_MAX / 3) 236 return (EINVAL); 237 238 somaxconn = val; 239 return (0); 240 } 241 SYSCTL_PROC(_kern_ipc, OID_AUTO, soacceptqueue, 242 CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_MPSAFE, 0, sizeof(int), 243 sysctl_somaxconn, "I", 244 "Maximum listen socket pending connection accept queue size"); 245 SYSCTL_PROC(_kern_ipc, KIPC_SOMAXCONN, somaxconn, 246 CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_SKIP | CTLFLAG_MPSAFE, 0, 247 sizeof(int), sysctl_somaxconn, "I", 248 "Maximum listen socket pending connection accept queue size (compat)"); 249 250 static int numopensockets; 251 SYSCTL_INT(_kern_ipc, OID_AUTO, numopensockets, CTLFLAG_RD, 252 &numopensockets, 0, "Number of open sockets"); 253 254 /* 255 * so_global_mtx protects so_gencnt, numopensockets, and the per-socket 256 * so_gencnt field. 257 */ 258 static struct mtx so_global_mtx; 259 MTX_SYSINIT(so_global_mtx, &so_global_mtx, "so_glabel", MTX_DEF); 260 261 /* 262 * General IPC sysctl name space, used by sockets and a variety of other IPC 263 * types. 264 */ 265 SYSCTL_NODE(_kern, KERN_IPC, ipc, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 266 "IPC"); 267 268 /* 269 * Initialize the socket subsystem and set up the socket 270 * memory allocator. 271 */ 272 static uma_zone_t socket_zone; 273 int maxsockets; 274 275 static void 276 socket_zone_change(void *tag) 277 { 278 279 maxsockets = uma_zone_set_max(socket_zone, maxsockets); 280 } 281 282 static void 283 socket_hhook_register(int subtype) 284 { 285 286 if (hhook_head_register(HHOOK_TYPE_SOCKET, subtype, 287 &V_socket_hhh[subtype], 288 HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0) 289 printf("%s: WARNING: unable to register hook\n", __func__); 290 } 291 292 static void 293 socket_hhook_deregister(int subtype) 294 { 295 296 if (hhook_head_deregister(V_socket_hhh[subtype]) != 0) 297 printf("%s: WARNING: unable to deregister hook\n", __func__); 298 } 299 300 static void 301 socket_init(void *tag) 302 { 303 304 socket_zone = uma_zcreate("socket", sizeof(struct socket), NULL, NULL, 305 NULL, NULL, UMA_ALIGN_PTR, 0); 306 maxsockets = uma_zone_set_max(socket_zone, maxsockets); 307 uma_zone_set_warning(socket_zone, "kern.ipc.maxsockets limit reached"); 308 EVENTHANDLER_REGISTER(maxsockets_change, socket_zone_change, NULL, 309 EVENTHANDLER_PRI_FIRST); 310 } 311 SYSINIT(socket, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY, socket_init, NULL); 312 313 static void 314 socket_vnet_init(const void *unused __unused) 315 { 316 int i; 317 318 /* We expect a contiguous range */ 319 for (i = 0; i <= HHOOK_SOCKET_LAST; i++) 320 socket_hhook_register(i); 321 } 322 VNET_SYSINIT(socket_vnet_init, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY, 323 socket_vnet_init, NULL); 324 325 static void 326 socket_vnet_uninit(const void *unused __unused) 327 { 328 int i; 329 330 for (i = 0; i <= HHOOK_SOCKET_LAST; i++) 331 socket_hhook_deregister(i); 332 } 333 VNET_SYSUNINIT(socket_vnet_uninit, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY, 334 socket_vnet_uninit, NULL); 335 336 /* 337 * Initialise maxsockets. This SYSINIT must be run after 338 * tunable_mbinit(). 339 */ 340 static void 341 init_maxsockets(void *ignored) 342 { 343 344 TUNABLE_INT_FETCH("kern.ipc.maxsockets", &maxsockets); 345 maxsockets = imax(maxsockets, maxfiles); 346 } 347 SYSINIT(param, SI_SUB_TUNABLES, SI_ORDER_ANY, init_maxsockets, NULL); 348 349 /* 350 * Sysctl to get and set the maximum global sockets limit. Notify protocols 351 * of the change so that they can update their dependent limits as required. 352 */ 353 static int 354 sysctl_maxsockets(SYSCTL_HANDLER_ARGS) 355 { 356 int error, newmaxsockets; 357 358 newmaxsockets = maxsockets; 359 error = sysctl_handle_int(oidp, &newmaxsockets, 0, req); 360 if (error == 0 && req->newptr && newmaxsockets != maxsockets) { 361 if (newmaxsockets > maxsockets && 362 newmaxsockets <= maxfiles) { 363 maxsockets = newmaxsockets; 364 EVENTHANDLER_INVOKE(maxsockets_change); 365 } else 366 error = EINVAL; 367 } 368 return (error); 369 } 370 SYSCTL_PROC(_kern_ipc, OID_AUTO, maxsockets, 371 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, &maxsockets, 0, 372 sysctl_maxsockets, "IU", 373 "Maximum number of sockets available"); 374 375 /* 376 * Socket operation routines. These routines are called by the routines in 377 * sys_socket.c or from a system process, and implement the semantics of 378 * socket operations by switching out to the protocol specific routines. 379 */ 380 381 /* 382 * Get a socket structure from our zone, and initialize it. Note that it 383 * would probably be better to allocate socket and PCB at the same time, but 384 * I'm not convinced that all the protocols can be easily modified to do 385 * this. 386 * 387 * soalloc() returns a socket with a ref count of 0. 388 */ 389 static struct socket * 390 soalloc(struct vnet *vnet) 391 { 392 struct socket *so; 393 394 so = uma_zalloc(socket_zone, M_NOWAIT | M_ZERO); 395 if (so == NULL) 396 return (NULL); 397 #ifdef MAC 398 if (mac_socket_init(so, M_NOWAIT) != 0) { 399 uma_zfree(socket_zone, so); 400 return (NULL); 401 } 402 #endif 403 if (khelp_init_osd(HELPER_CLASS_SOCKET, &so->osd)) { 404 uma_zfree(socket_zone, so); 405 return (NULL); 406 } 407 408 /* 409 * The socket locking protocol allows to lock 2 sockets at a time, 410 * however, the first one must be a listening socket. WITNESS lacks 411 * a feature to change class of an existing lock, so we use DUPOK. 412 */ 413 mtx_init(&so->so_lock, "socket", NULL, MTX_DEF | MTX_DUPOK); 414 mtx_init(&so->so_snd_mtx, "so_snd", NULL, MTX_DEF); 415 mtx_init(&so->so_rcv_mtx, "so_rcv", NULL, MTX_DEF); 416 so->so_rcv.sb_sel = &so->so_rdsel; 417 so->so_snd.sb_sel = &so->so_wrsel; 418 sx_init(&so->so_snd_sx, "so_snd_sx"); 419 sx_init(&so->so_rcv_sx, "so_rcv_sx"); 420 TAILQ_INIT(&so->so_snd.sb_aiojobq); 421 TAILQ_INIT(&so->so_rcv.sb_aiojobq); 422 TASK_INIT(&so->so_snd.sb_aiotask, 0, soaio_snd, so); 423 TASK_INIT(&so->so_rcv.sb_aiotask, 0, soaio_rcv, so); 424 #ifdef VIMAGE 425 VNET_ASSERT(vnet != NULL, ("%s:%d vnet is NULL, so=%p", 426 __func__, __LINE__, so)); 427 so->so_vnet = vnet; 428 #endif 429 /* We shouldn't need the so_global_mtx */ 430 if (hhook_run_socket(so, NULL, HHOOK_SOCKET_CREATE)) { 431 /* Do we need more comprehensive error returns? */ 432 uma_zfree(socket_zone, so); 433 return (NULL); 434 } 435 mtx_lock(&so_global_mtx); 436 so->so_gencnt = ++so_gencnt; 437 ++numopensockets; 438 #ifdef VIMAGE 439 vnet->vnet_sockcnt++; 440 #endif 441 mtx_unlock(&so_global_mtx); 442 443 return (so); 444 } 445 446 /* 447 * Free the storage associated with a socket at the socket layer, tear down 448 * locks, labels, etc. All protocol state is assumed already to have been 449 * torn down (and possibly never set up) by the caller. 450 */ 451 void 452 sodealloc(struct socket *so) 453 { 454 455 KASSERT(so->so_count == 0, ("sodealloc(): so_count %d", so->so_count)); 456 KASSERT(so->so_pcb == NULL, ("sodealloc(): so_pcb != NULL")); 457 458 mtx_lock(&so_global_mtx); 459 so->so_gencnt = ++so_gencnt; 460 --numopensockets; /* Could be below, but faster here. */ 461 #ifdef VIMAGE 462 VNET_ASSERT(so->so_vnet != NULL, ("%s:%d so_vnet is NULL, so=%p", 463 __func__, __LINE__, so)); 464 so->so_vnet->vnet_sockcnt--; 465 #endif 466 mtx_unlock(&so_global_mtx); 467 #ifdef MAC 468 mac_socket_destroy(so); 469 #endif 470 hhook_run_socket(so, NULL, HHOOK_SOCKET_CLOSE); 471 472 khelp_destroy_osd(&so->osd); 473 if (SOLISTENING(so)) { 474 if (so->sol_accept_filter != NULL) 475 accept_filt_setopt(so, NULL); 476 } else { 477 if (so->so_rcv.sb_hiwat) 478 (void)chgsbsize(so->so_cred->cr_uidinfo, 479 &so->so_rcv.sb_hiwat, 0, RLIM_INFINITY); 480 if (so->so_snd.sb_hiwat) 481 (void)chgsbsize(so->so_cred->cr_uidinfo, 482 &so->so_snd.sb_hiwat, 0, RLIM_INFINITY); 483 sx_destroy(&so->so_snd_sx); 484 sx_destroy(&so->so_rcv_sx); 485 mtx_destroy(&so->so_snd_mtx); 486 mtx_destroy(&so->so_rcv_mtx); 487 } 488 crfree(so->so_cred); 489 mtx_destroy(&so->so_lock); 490 uma_zfree(socket_zone, so); 491 } 492 493 /* 494 * socreate returns a socket with a ref count of 1 and a file descriptor 495 * reference. The socket should be closed with soclose(). 496 */ 497 int 498 socreate(int dom, struct socket **aso, int type, int proto, 499 struct ucred *cred, struct thread *td) 500 { 501 struct protosw *prp; 502 struct socket *so; 503 int error; 504 505 /* 506 * XXX: divert(4) historically abused PF_INET. Keep this compatibility 507 * shim until all applications have been updated. 508 */ 509 if (__predict_false(dom == PF_INET && type == SOCK_RAW && 510 proto == IPPROTO_DIVERT)) { 511 dom = PF_DIVERT; 512 printf("%s uses obsolete way to create divert(4) socket\n", 513 td->td_proc->p_comm); 514 } 515 516 prp = pffindproto(dom, type, proto); 517 if (prp == NULL) { 518 /* No support for domain. */ 519 if (pffinddomain(dom) == NULL) 520 return (EAFNOSUPPORT); 521 /* No support for socket type. */ 522 if (proto == 0 && type != 0) 523 return (EPROTOTYPE); 524 return (EPROTONOSUPPORT); 525 } 526 527 MPASS(prp->pr_attach); 528 529 if (IN_CAPABILITY_MODE(td) && (prp->pr_flags & PR_CAPATTACH) == 0) 530 return (ECAPMODE); 531 532 if (prison_check_af(cred, prp->pr_domain->dom_family) != 0) 533 return (EPROTONOSUPPORT); 534 535 so = soalloc(CRED_TO_VNET(cred)); 536 if (so == NULL) 537 return (ENOBUFS); 538 539 so->so_type = type; 540 so->so_cred = crhold(cred); 541 if ((prp->pr_domain->dom_family == PF_INET) || 542 (prp->pr_domain->dom_family == PF_INET6) || 543 (prp->pr_domain->dom_family == PF_ROUTE)) 544 so->so_fibnum = td->td_proc->p_fibnum; 545 else 546 so->so_fibnum = 0; 547 so->so_proto = prp; 548 #ifdef MAC 549 mac_socket_create(cred, so); 550 #endif 551 knlist_init(&so->so_rdsel.si_note, so, so_rdknl_lock, so_rdknl_unlock, 552 so_rdknl_assert_lock); 553 knlist_init(&so->so_wrsel.si_note, so, so_wrknl_lock, so_wrknl_unlock, 554 so_wrknl_assert_lock); 555 if ((prp->pr_flags & PR_SOCKBUF) == 0) { 556 so->so_snd.sb_mtx = &so->so_snd_mtx; 557 so->so_rcv.sb_mtx = &so->so_rcv_mtx; 558 } 559 /* 560 * Auto-sizing of socket buffers is managed by the protocols and 561 * the appropriate flags must be set in the pru_attach function. 562 */ 563 CURVNET_SET(so->so_vnet); 564 error = prp->pr_attach(so, proto, td); 565 CURVNET_RESTORE(); 566 if (error) { 567 sodealloc(so); 568 return (error); 569 } 570 soref(so); 571 *aso = so; 572 return (0); 573 } 574 575 #ifdef REGRESSION 576 static int regression_sonewconn_earlytest = 1; 577 SYSCTL_INT(_regression, OID_AUTO, sonewconn_earlytest, CTLFLAG_RW, 578 ®ression_sonewconn_earlytest, 0, "Perform early sonewconn limit test"); 579 #endif 580 581 static int sooverprio = LOG_DEBUG; 582 SYSCTL_INT(_kern_ipc, OID_AUTO, sooverprio, CTLFLAG_RW, 583 &sooverprio, 0, "Log priority for listen socket overflows: 0..7 or -1 to disable"); 584 585 static struct timeval overinterval = { 60, 0 }; 586 SYSCTL_TIMEVAL_SEC(_kern_ipc, OID_AUTO, sooverinterval, CTLFLAG_RW, 587 &overinterval, 588 "Delay in seconds between warnings for listen socket overflows"); 589 590 /* 591 * When an attempt at a new connection is noted on a socket which supports 592 * accept(2), the protocol has two options: 593 * 1) Call legacy sonewconn() function, which would call protocol attach 594 * method, same as used for socket(2). 595 * 2) Call solisten_clone(), do attach that is specific to a cloned connection, 596 * and then call solisten_enqueue(). 597 * 598 * Note: the ref count on the socket is 0 on return. 599 */ 600 struct socket * 601 solisten_clone(struct socket *head) 602 { 603 struct sbuf descrsb; 604 struct socket *so; 605 int len, overcount; 606 u_int qlen; 607 const char localprefix[] = "local:"; 608 char descrbuf[SUNPATHLEN + sizeof(localprefix)]; 609 #if defined(INET6) 610 char addrbuf[INET6_ADDRSTRLEN]; 611 #elif defined(INET) 612 char addrbuf[INET_ADDRSTRLEN]; 613 #endif 614 bool dolog, over; 615 616 SOLISTEN_LOCK(head); 617 over = (head->sol_qlen > 3 * head->sol_qlimit / 2); 618 #ifdef REGRESSION 619 if (regression_sonewconn_earlytest && over) { 620 #else 621 if (over) { 622 #endif 623 head->sol_overcount++; 624 dolog = (sooverprio >= 0) && 625 !!ratecheck(&head->sol_lastover, &overinterval); 626 627 /* 628 * If we're going to log, copy the overflow count and queue 629 * length from the listen socket before dropping the lock. 630 * Also, reset the overflow count. 631 */ 632 if (dolog) { 633 overcount = head->sol_overcount; 634 head->sol_overcount = 0; 635 qlen = head->sol_qlen; 636 } 637 SOLISTEN_UNLOCK(head); 638 639 if (dolog) { 640 /* 641 * Try to print something descriptive about the 642 * socket for the error message. 643 */ 644 sbuf_new(&descrsb, descrbuf, sizeof(descrbuf), 645 SBUF_FIXEDLEN); 646 switch (head->so_proto->pr_domain->dom_family) { 647 #if defined(INET) || defined(INET6) 648 #ifdef INET 649 case AF_INET: 650 #endif 651 #ifdef INET6 652 case AF_INET6: 653 if (head->so_proto->pr_domain->dom_family == 654 AF_INET6 || 655 (sotoinpcb(head)->inp_inc.inc_flags & 656 INC_ISIPV6)) { 657 ip6_sprintf(addrbuf, 658 &sotoinpcb(head)->inp_inc.inc6_laddr); 659 sbuf_printf(&descrsb, "[%s]", addrbuf); 660 } else 661 #endif 662 { 663 #ifdef INET 664 inet_ntoa_r( 665 sotoinpcb(head)->inp_inc.inc_laddr, 666 addrbuf); 667 sbuf_cat(&descrsb, addrbuf); 668 #endif 669 } 670 sbuf_printf(&descrsb, ":%hu (proto %u)", 671 ntohs(sotoinpcb(head)->inp_inc.inc_lport), 672 head->so_proto->pr_protocol); 673 break; 674 #endif /* INET || INET6 */ 675 case AF_UNIX: 676 sbuf_cat(&descrsb, localprefix); 677 if (sotounpcb(head)->unp_addr != NULL) 678 len = 679 sotounpcb(head)->unp_addr->sun_len - 680 offsetof(struct sockaddr_un, 681 sun_path); 682 else 683 len = 0; 684 if (len > 0) 685 sbuf_bcat(&descrsb, 686 sotounpcb(head)->unp_addr->sun_path, 687 len); 688 else 689 sbuf_cat(&descrsb, "(unknown)"); 690 break; 691 } 692 693 /* 694 * If we can't print something more specific, at least 695 * print the domain name. 696 */ 697 if (sbuf_finish(&descrsb) != 0 || 698 sbuf_len(&descrsb) <= 0) { 699 sbuf_clear(&descrsb); 700 sbuf_cat(&descrsb, 701 head->so_proto->pr_domain->dom_name ?: 702 "unknown"); 703 sbuf_finish(&descrsb); 704 } 705 KASSERT(sbuf_len(&descrsb) > 0, 706 ("%s: sbuf creation failed", __func__)); 707 /* 708 * Preserve the historic listen queue overflow log 709 * message, that starts with "sonewconn:". It has 710 * been known to sysadmins for years and also test 711 * sys/kern/sonewconn_overflow checks for it. 712 */ 713 if (head->so_cred == 0) { 714 log(LOG_PRI(sooverprio), 715 "sonewconn: pcb %p (%s): " 716 "Listen queue overflow: %i already in " 717 "queue awaiting acceptance (%d " 718 "occurrences)\n", head->so_pcb, 719 sbuf_data(&descrsb), 720 qlen, overcount); 721 } else { 722 log(LOG_PRI(sooverprio), 723 "sonewconn: pcb %p (%s): " 724 "Listen queue overflow: " 725 "%i already in queue awaiting acceptance " 726 "(%d occurrences), euid %d, rgid %d, jail %s\n", 727 head->so_pcb, sbuf_data(&descrsb), qlen, 728 overcount, head->so_cred->cr_uid, 729 head->so_cred->cr_rgid, 730 head->so_cred->cr_prison ? 731 head->so_cred->cr_prison->pr_name : 732 "not_jailed"); 733 } 734 sbuf_delete(&descrsb); 735 736 overcount = 0; 737 } 738 739 return (NULL); 740 } 741 SOLISTEN_UNLOCK(head); 742 VNET_ASSERT(head->so_vnet != NULL, ("%s: so %p vnet is NULL", 743 __func__, head)); 744 so = soalloc(head->so_vnet); 745 if (so == NULL) { 746 log(LOG_DEBUG, "%s: pcb %p: New socket allocation failure: " 747 "limit reached or out of memory\n", 748 __func__, head->so_pcb); 749 return (NULL); 750 } 751 so->so_listen = head; 752 so->so_type = head->so_type; 753 so->so_options = head->so_options & ~SO_ACCEPTCONN; 754 so->so_linger = head->so_linger; 755 so->so_state = head->so_state; 756 so->so_fibnum = head->so_fibnum; 757 so->so_proto = head->so_proto; 758 so->so_cred = crhold(head->so_cred); 759 #ifdef MAC 760 mac_socket_newconn(head, so); 761 #endif 762 knlist_init(&so->so_rdsel.si_note, so, so_rdknl_lock, so_rdknl_unlock, 763 so_rdknl_assert_lock); 764 knlist_init(&so->so_wrsel.si_note, so, so_wrknl_lock, so_wrknl_unlock, 765 so_wrknl_assert_lock); 766 VNET_SO_ASSERT(head); 767 if (soreserve(so, head->sol_sbsnd_hiwat, head->sol_sbrcv_hiwat)) { 768 sodealloc(so); 769 log(LOG_DEBUG, "%s: pcb %p: soreserve() failed\n", 770 __func__, head->so_pcb); 771 return (NULL); 772 } 773 so->so_rcv.sb_lowat = head->sol_sbrcv_lowat; 774 so->so_snd.sb_lowat = head->sol_sbsnd_lowat; 775 so->so_rcv.sb_timeo = head->sol_sbrcv_timeo; 776 so->so_snd.sb_timeo = head->sol_sbsnd_timeo; 777 so->so_rcv.sb_flags = head->sol_sbrcv_flags & SB_AUTOSIZE; 778 so->so_snd.sb_flags = head->sol_sbsnd_flags & SB_AUTOSIZE; 779 if ((so->so_proto->pr_flags & PR_SOCKBUF) == 0) { 780 so->so_snd.sb_mtx = &so->so_snd_mtx; 781 so->so_rcv.sb_mtx = &so->so_rcv_mtx; 782 } 783 784 return (so); 785 } 786 787 /* Connstatus may be 0, or SS_ISCONFIRMING, or SS_ISCONNECTED. */ 788 struct socket * 789 sonewconn(struct socket *head, int connstatus) 790 { 791 struct socket *so; 792 793 if ((so = solisten_clone(head)) == NULL) 794 return (NULL); 795 796 if (so->so_proto->pr_attach(so, 0, NULL) != 0) { 797 sodealloc(so); 798 log(LOG_DEBUG, "%s: pcb %p: pr_attach() failed\n", 799 __func__, head->so_pcb); 800 return (NULL); 801 } 802 803 (void)solisten_enqueue(so, connstatus); 804 805 return (so); 806 } 807 808 /* 809 * Enqueue socket cloned by solisten_clone() to the listen queue of the 810 * listener it has been cloned from. 811 * 812 * Return 'true' if socket landed on complete queue, otherwise 'false'. 813 */ 814 bool 815 solisten_enqueue(struct socket *so, int connstatus) 816 { 817 struct socket *head = so->so_listen; 818 819 MPASS(refcount_load(&so->so_count) == 0); 820 refcount_init(&so->so_count, 1); 821 822 SOLISTEN_LOCK(head); 823 if (head->sol_accept_filter != NULL) 824 connstatus = 0; 825 so->so_state |= connstatus; 826 soref(head); /* A socket on (in)complete queue refs head. */ 827 if (connstatus) { 828 TAILQ_INSERT_TAIL(&head->sol_comp, so, so_list); 829 so->so_qstate = SQ_COMP; 830 head->sol_qlen++; 831 solisten_wakeup(head); /* unlocks */ 832 return (true); 833 } else { 834 /* 835 * Keep removing sockets from the head until there's room for 836 * us to insert on the tail. In pre-locking revisions, this 837 * was a simple if(), but as we could be racing with other 838 * threads and soabort() requires dropping locks, we must 839 * loop waiting for the condition to be true. 840 */ 841 while (head->sol_incqlen > head->sol_qlimit) { 842 struct socket *sp; 843 844 sp = TAILQ_FIRST(&head->sol_incomp); 845 TAILQ_REMOVE(&head->sol_incomp, sp, so_list); 846 head->sol_incqlen--; 847 SOCK_LOCK(sp); 848 sp->so_qstate = SQ_NONE; 849 sp->so_listen = NULL; 850 SOCK_UNLOCK(sp); 851 sorele_locked(head); /* does SOLISTEN_UNLOCK, head stays */ 852 soabort(sp); 853 SOLISTEN_LOCK(head); 854 } 855 TAILQ_INSERT_TAIL(&head->sol_incomp, so, so_list); 856 so->so_qstate = SQ_INCOMP; 857 head->sol_incqlen++; 858 SOLISTEN_UNLOCK(head); 859 return (false); 860 } 861 } 862 863 #if defined(SCTP) || defined(SCTP_SUPPORT) 864 /* 865 * Socket part of sctp_peeloff(). Detach a new socket from an 866 * association. The new socket is returned with a reference. 867 * 868 * XXXGL: reduce copy-paste with solisten_clone(). 869 */ 870 struct socket * 871 sopeeloff(struct socket *head) 872 { 873 struct socket *so; 874 875 VNET_ASSERT(head->so_vnet != NULL, ("%s:%d so_vnet is NULL, head=%p", 876 __func__, __LINE__, head)); 877 so = soalloc(head->so_vnet); 878 if (so == NULL) { 879 log(LOG_DEBUG, "%s: pcb %p: New socket allocation failure: " 880 "limit reached or out of memory\n", 881 __func__, head->so_pcb); 882 return (NULL); 883 } 884 so->so_type = head->so_type; 885 so->so_options = head->so_options; 886 so->so_linger = head->so_linger; 887 so->so_state = (head->so_state & SS_NBIO) | SS_ISCONNECTED; 888 so->so_fibnum = head->so_fibnum; 889 so->so_proto = head->so_proto; 890 so->so_cred = crhold(head->so_cred); 891 #ifdef MAC 892 mac_socket_newconn(head, so); 893 #endif 894 knlist_init(&so->so_rdsel.si_note, so, so_rdknl_lock, so_rdknl_unlock, 895 so_rdknl_assert_lock); 896 knlist_init(&so->so_wrsel.si_note, so, so_wrknl_lock, so_wrknl_unlock, 897 so_wrknl_assert_lock); 898 VNET_SO_ASSERT(head); 899 if (soreserve(so, head->so_snd.sb_hiwat, head->so_rcv.sb_hiwat)) { 900 sodealloc(so); 901 log(LOG_DEBUG, "%s: pcb %p: soreserve() failed\n", 902 __func__, head->so_pcb); 903 return (NULL); 904 } 905 if ((*so->so_proto->pr_attach)(so, 0, NULL)) { 906 sodealloc(so); 907 log(LOG_DEBUG, "%s: pcb %p: pru_attach() failed\n", 908 __func__, head->so_pcb); 909 return (NULL); 910 } 911 so->so_rcv.sb_lowat = head->so_rcv.sb_lowat; 912 so->so_snd.sb_lowat = head->so_snd.sb_lowat; 913 so->so_rcv.sb_timeo = head->so_rcv.sb_timeo; 914 so->so_snd.sb_timeo = head->so_snd.sb_timeo; 915 so->so_rcv.sb_flags |= head->so_rcv.sb_flags & SB_AUTOSIZE; 916 so->so_snd.sb_flags |= head->so_snd.sb_flags & SB_AUTOSIZE; 917 918 soref(so); 919 920 return (so); 921 } 922 #endif /* SCTP */ 923 924 int 925 sobind(struct socket *so, struct sockaddr *nam, struct thread *td) 926 { 927 int error; 928 929 CURVNET_SET(so->so_vnet); 930 error = so->so_proto->pr_bind(so, nam, td); 931 CURVNET_RESTORE(); 932 return (error); 933 } 934 935 int 936 sobindat(int fd, struct socket *so, struct sockaddr *nam, struct thread *td) 937 { 938 int error; 939 940 CURVNET_SET(so->so_vnet); 941 error = so->so_proto->pr_bindat(fd, so, nam, td); 942 CURVNET_RESTORE(); 943 return (error); 944 } 945 946 /* 947 * solisten() transitions a socket from a non-listening state to a listening 948 * state, but can also be used to update the listen queue depth on an 949 * existing listen socket. The protocol will call back into the sockets 950 * layer using solisten_proto_check() and solisten_proto() to check and set 951 * socket-layer listen state. Call backs are used so that the protocol can 952 * acquire both protocol and socket layer locks in whatever order is required 953 * by the protocol. 954 * 955 * Protocol implementors are advised to hold the socket lock across the 956 * socket-layer test and set to avoid races at the socket layer. 957 */ 958 int 959 solisten(struct socket *so, int backlog, struct thread *td) 960 { 961 int error; 962 963 CURVNET_SET(so->so_vnet); 964 error = so->so_proto->pr_listen(so, backlog, td); 965 CURVNET_RESTORE(); 966 return (error); 967 } 968 969 /* 970 * Prepare for a call to solisten_proto(). Acquire all socket buffer locks in 971 * order to interlock with socket I/O. 972 */ 973 int 974 solisten_proto_check(struct socket *so) 975 { 976 SOCK_LOCK_ASSERT(so); 977 978 if ((so->so_state & (SS_ISCONNECTED | SS_ISCONNECTING | 979 SS_ISDISCONNECTING)) != 0) 980 return (EINVAL); 981 982 /* 983 * Sleeping is not permitted here, so simply fail if userspace is 984 * attempting to transmit or receive on the socket. This kind of 985 * transient failure is not ideal, but it should occur only if userspace 986 * is misusing the socket interfaces. 987 */ 988 if (!sx_try_xlock(&so->so_snd_sx)) 989 return (EAGAIN); 990 if (!sx_try_xlock(&so->so_rcv_sx)) { 991 sx_xunlock(&so->so_snd_sx); 992 return (EAGAIN); 993 } 994 mtx_lock(&so->so_snd_mtx); 995 mtx_lock(&so->so_rcv_mtx); 996 997 /* Interlock with soo_aio_queue() and KTLS. */ 998 if (!SOLISTENING(so)) { 999 bool ktls; 1000 1001 #ifdef KERN_TLS 1002 ktls = so->so_snd.sb_tls_info != NULL || 1003 so->so_rcv.sb_tls_info != NULL; 1004 #else 1005 ktls = false; 1006 #endif 1007 if (ktls || 1008 (so->so_snd.sb_flags & (SB_AIO | SB_AIO_RUNNING)) != 0 || 1009 (so->so_rcv.sb_flags & (SB_AIO | SB_AIO_RUNNING)) != 0) { 1010 solisten_proto_abort(so); 1011 return (EINVAL); 1012 } 1013 } 1014 1015 return (0); 1016 } 1017 1018 /* 1019 * Undo the setup done by solisten_proto_check(). 1020 */ 1021 void 1022 solisten_proto_abort(struct socket *so) 1023 { 1024 mtx_unlock(&so->so_snd_mtx); 1025 mtx_unlock(&so->so_rcv_mtx); 1026 sx_xunlock(&so->so_snd_sx); 1027 sx_xunlock(&so->so_rcv_sx); 1028 } 1029 1030 void 1031 solisten_proto(struct socket *so, int backlog) 1032 { 1033 int sbrcv_lowat, sbsnd_lowat; 1034 u_int sbrcv_hiwat, sbsnd_hiwat; 1035 short sbrcv_flags, sbsnd_flags; 1036 sbintime_t sbrcv_timeo, sbsnd_timeo; 1037 1038 SOCK_LOCK_ASSERT(so); 1039 KASSERT((so->so_state & (SS_ISCONNECTED | SS_ISCONNECTING | 1040 SS_ISDISCONNECTING)) == 0, 1041 ("%s: bad socket state %p", __func__, so)); 1042 1043 if (SOLISTENING(so)) 1044 goto listening; 1045 1046 /* 1047 * Change this socket to listening state. 1048 */ 1049 sbrcv_lowat = so->so_rcv.sb_lowat; 1050 sbsnd_lowat = so->so_snd.sb_lowat; 1051 sbrcv_hiwat = so->so_rcv.sb_hiwat; 1052 sbsnd_hiwat = so->so_snd.sb_hiwat; 1053 sbrcv_flags = so->so_rcv.sb_flags; 1054 sbsnd_flags = so->so_snd.sb_flags; 1055 sbrcv_timeo = so->so_rcv.sb_timeo; 1056 sbsnd_timeo = so->so_snd.sb_timeo; 1057 1058 sbdestroy(so, SO_SND); 1059 sbdestroy(so, SO_RCV); 1060 1061 #ifdef INVARIANTS 1062 bzero(&so->so_rcv, 1063 sizeof(struct socket) - offsetof(struct socket, so_rcv)); 1064 #endif 1065 1066 so->sol_sbrcv_lowat = sbrcv_lowat; 1067 so->sol_sbsnd_lowat = sbsnd_lowat; 1068 so->sol_sbrcv_hiwat = sbrcv_hiwat; 1069 so->sol_sbsnd_hiwat = sbsnd_hiwat; 1070 so->sol_sbrcv_flags = sbrcv_flags; 1071 so->sol_sbsnd_flags = sbsnd_flags; 1072 so->sol_sbrcv_timeo = sbrcv_timeo; 1073 so->sol_sbsnd_timeo = sbsnd_timeo; 1074 1075 so->sol_qlen = so->sol_incqlen = 0; 1076 TAILQ_INIT(&so->sol_incomp); 1077 TAILQ_INIT(&so->sol_comp); 1078 1079 so->sol_accept_filter = NULL; 1080 so->sol_accept_filter_arg = NULL; 1081 so->sol_accept_filter_str = NULL; 1082 1083 so->sol_upcall = NULL; 1084 so->sol_upcallarg = NULL; 1085 1086 so->so_options |= SO_ACCEPTCONN; 1087 1088 listening: 1089 if (backlog < 0 || backlog > somaxconn) 1090 backlog = somaxconn; 1091 so->sol_qlimit = backlog; 1092 1093 mtx_unlock(&so->so_snd_mtx); 1094 mtx_unlock(&so->so_rcv_mtx); 1095 sx_xunlock(&so->so_snd_sx); 1096 sx_xunlock(&so->so_rcv_sx); 1097 } 1098 1099 /* 1100 * Wakeup listeners/subsystems once we have a complete connection. 1101 * Enters with lock, returns unlocked. 1102 */ 1103 void 1104 solisten_wakeup(struct socket *sol) 1105 { 1106 1107 if (sol->sol_upcall != NULL) 1108 (void )sol->sol_upcall(sol, sol->sol_upcallarg, M_NOWAIT); 1109 else { 1110 selwakeuppri(&sol->so_rdsel, PSOCK); 1111 KNOTE_LOCKED(&sol->so_rdsel.si_note, 0); 1112 } 1113 SOLISTEN_UNLOCK(sol); 1114 wakeup_one(&sol->sol_comp); 1115 if ((sol->so_state & SS_ASYNC) && sol->so_sigio != NULL) 1116 pgsigio(&sol->so_sigio, SIGIO, 0); 1117 } 1118 1119 /* 1120 * Return single connection off a listening socket queue. Main consumer of 1121 * the function is kern_accept4(). Some modules, that do their own accept 1122 * management also use the function. The socket reference held by the 1123 * listen queue is handed to the caller. 1124 * 1125 * Listening socket must be locked on entry and is returned unlocked on 1126 * return. 1127 * The flags argument is set of accept4(2) flags and ACCEPT4_INHERIT. 1128 */ 1129 int 1130 solisten_dequeue(struct socket *head, struct socket **ret, int flags) 1131 { 1132 struct socket *so; 1133 int error; 1134 1135 SOLISTEN_LOCK_ASSERT(head); 1136 1137 while (!(head->so_state & SS_NBIO) && TAILQ_EMPTY(&head->sol_comp) && 1138 head->so_error == 0) { 1139 error = msleep(&head->sol_comp, SOCK_MTX(head), PSOCK | PCATCH, 1140 "accept", 0); 1141 if (error != 0) { 1142 SOLISTEN_UNLOCK(head); 1143 return (error); 1144 } 1145 } 1146 if (head->so_error) { 1147 error = head->so_error; 1148 head->so_error = 0; 1149 } else if ((head->so_state & SS_NBIO) && TAILQ_EMPTY(&head->sol_comp)) 1150 error = EWOULDBLOCK; 1151 else 1152 error = 0; 1153 if (error) { 1154 SOLISTEN_UNLOCK(head); 1155 return (error); 1156 } 1157 so = TAILQ_FIRST(&head->sol_comp); 1158 SOCK_LOCK(so); 1159 KASSERT(so->so_qstate == SQ_COMP, 1160 ("%s: so %p not SQ_COMP", __func__, so)); 1161 head->sol_qlen--; 1162 so->so_qstate = SQ_NONE; 1163 so->so_listen = NULL; 1164 TAILQ_REMOVE(&head->sol_comp, so, so_list); 1165 if (flags & ACCEPT4_INHERIT) 1166 so->so_state |= (head->so_state & SS_NBIO); 1167 else 1168 so->so_state |= (flags & SOCK_NONBLOCK) ? SS_NBIO : 0; 1169 SOCK_UNLOCK(so); 1170 sorele_locked(head); 1171 1172 *ret = so; 1173 return (0); 1174 } 1175 1176 /* 1177 * Free socket upon release of the very last reference. 1178 */ 1179 static void 1180 sofree(struct socket *so) 1181 { 1182 struct protosw *pr = so->so_proto; 1183 1184 SOCK_LOCK_ASSERT(so); 1185 KASSERT(refcount_load(&so->so_count) == 0, 1186 ("%s: so %p has references", __func__, so)); 1187 KASSERT(SOLISTENING(so) || so->so_qstate == SQ_NONE, 1188 ("%s: so %p is on listen queue", __func__, so)); 1189 1190 SOCK_UNLOCK(so); 1191 1192 if (so->so_dtor != NULL) 1193 so->so_dtor(so); 1194 1195 VNET_SO_ASSERT(so); 1196 if ((pr->pr_flags & PR_RIGHTS) && !SOLISTENING(so)) { 1197 MPASS(pr->pr_domain->dom_dispose != NULL); 1198 (*pr->pr_domain->dom_dispose)(so); 1199 } 1200 if (pr->pr_detach != NULL) 1201 pr->pr_detach(so); 1202 1203 /* 1204 * From this point on, we assume that no other references to this 1205 * socket exist anywhere else in the stack. Therefore, no locks need 1206 * to be acquired or held. 1207 */ 1208 if (!(pr->pr_flags & PR_SOCKBUF) && !SOLISTENING(so)) { 1209 sbdestroy(so, SO_SND); 1210 sbdestroy(so, SO_RCV); 1211 } 1212 seldrain(&so->so_rdsel); 1213 seldrain(&so->so_wrsel); 1214 knlist_destroy(&so->so_rdsel.si_note); 1215 knlist_destroy(&so->so_wrsel.si_note); 1216 sodealloc(so); 1217 } 1218 1219 /* 1220 * Release a reference on a socket while holding the socket lock. 1221 * Unlocks the socket lock before returning. 1222 */ 1223 void 1224 sorele_locked(struct socket *so) 1225 { 1226 SOCK_LOCK_ASSERT(so); 1227 if (refcount_release(&so->so_count)) 1228 sofree(so); 1229 else 1230 SOCK_UNLOCK(so); 1231 } 1232 1233 /* 1234 * Close a socket on last file table reference removal. Initiate disconnect 1235 * if connected. Free socket when disconnect complete. 1236 * 1237 * This function will sorele() the socket. Note that soclose() may be called 1238 * prior to the ref count reaching zero. The actual socket structure will 1239 * not be freed until the ref count reaches zero. 1240 */ 1241 int 1242 soclose(struct socket *so) 1243 { 1244 struct accept_queue lqueue; 1245 int error = 0; 1246 bool listening, last __diagused; 1247 1248 CURVNET_SET(so->so_vnet); 1249 funsetown(&so->so_sigio); 1250 if (so->so_state & SS_ISCONNECTED) { 1251 if ((so->so_state & SS_ISDISCONNECTING) == 0) { 1252 error = sodisconnect(so); 1253 if (error) { 1254 if (error == ENOTCONN) 1255 error = 0; 1256 goto drop; 1257 } 1258 } 1259 1260 if ((so->so_options & SO_LINGER) != 0 && so->so_linger != 0) { 1261 if ((so->so_state & SS_ISDISCONNECTING) && 1262 (so->so_state & SS_NBIO)) 1263 goto drop; 1264 while (so->so_state & SS_ISCONNECTED) { 1265 error = tsleep(&so->so_timeo, 1266 PSOCK | PCATCH, "soclos", 1267 so->so_linger * hz); 1268 if (error) 1269 break; 1270 } 1271 } 1272 } 1273 1274 drop: 1275 if (so->so_proto->pr_close != NULL) 1276 so->so_proto->pr_close(so); 1277 1278 SOCK_LOCK(so); 1279 if ((listening = SOLISTENING(so))) { 1280 struct socket *sp; 1281 1282 TAILQ_INIT(&lqueue); 1283 TAILQ_SWAP(&lqueue, &so->sol_incomp, socket, so_list); 1284 TAILQ_CONCAT(&lqueue, &so->sol_comp, so_list); 1285 1286 so->sol_qlen = so->sol_incqlen = 0; 1287 1288 TAILQ_FOREACH(sp, &lqueue, so_list) { 1289 SOCK_LOCK(sp); 1290 sp->so_qstate = SQ_NONE; 1291 sp->so_listen = NULL; 1292 SOCK_UNLOCK(sp); 1293 last = refcount_release(&so->so_count); 1294 KASSERT(!last, ("%s: released last reference for %p", 1295 __func__, so)); 1296 } 1297 } 1298 sorele_locked(so); 1299 if (listening) { 1300 struct socket *sp, *tsp; 1301 1302 TAILQ_FOREACH_SAFE(sp, &lqueue, so_list, tsp) 1303 soabort(sp); 1304 } 1305 CURVNET_RESTORE(); 1306 return (error); 1307 } 1308 1309 /* 1310 * soabort() is used to abruptly tear down a connection, such as when a 1311 * resource limit is reached (listen queue depth exceeded), or if a listen 1312 * socket is closed while there are sockets waiting to be accepted. 1313 * 1314 * This interface is tricky, because it is called on an unreferenced socket, 1315 * and must be called only by a thread that has actually removed the socket 1316 * from the listen queue it was on. Likely this thread holds the last 1317 * reference on the socket and soabort() will proceed with sofree(). But 1318 * it might be not the last, as the sockets on the listen queues are seen 1319 * from the protocol side. 1320 * 1321 * This interface will call into the protocol code, so must not be called 1322 * with any socket locks held. Protocols do call it while holding their own 1323 * recursible protocol mutexes, but this is something that should be subject 1324 * to review in the future. 1325 * 1326 * Usually socket should have a single reference left, but this is not a 1327 * requirement. In the past, when we have had named references for file 1328 * descriptor and protocol, we asserted that none of them are being held. 1329 */ 1330 void 1331 soabort(struct socket *so) 1332 { 1333 1334 VNET_SO_ASSERT(so); 1335 1336 if (so->so_proto->pr_abort != NULL) 1337 so->so_proto->pr_abort(so); 1338 SOCK_LOCK(so); 1339 sorele_locked(so); 1340 } 1341 1342 int 1343 soaccept(struct socket *so, struct sockaddr **nam) 1344 { 1345 int error; 1346 1347 CURVNET_SET(so->so_vnet); 1348 error = so->so_proto->pr_accept(so, nam); 1349 CURVNET_RESTORE(); 1350 return (error); 1351 } 1352 1353 int 1354 soconnect(struct socket *so, struct sockaddr *nam, struct thread *td) 1355 { 1356 1357 return (soconnectat(AT_FDCWD, so, nam, td)); 1358 } 1359 1360 int 1361 soconnectat(int fd, struct socket *so, struct sockaddr *nam, struct thread *td) 1362 { 1363 int error; 1364 1365 CURVNET_SET(so->so_vnet); 1366 1367 /* 1368 * If protocol is connection-based, can only connect once. 1369 * Otherwise, if connected, try to disconnect first. This allows 1370 * user to disconnect by connecting to, e.g., a null address. 1371 * 1372 * Note, this check is racy and may need to be re-evaluated at the 1373 * protocol layer. 1374 */ 1375 if (so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING) && 1376 ((so->so_proto->pr_flags & PR_CONNREQUIRED) || 1377 (error = sodisconnect(so)))) { 1378 error = EISCONN; 1379 } else { 1380 /* 1381 * Prevent accumulated error from previous connection from 1382 * biting us. 1383 */ 1384 so->so_error = 0; 1385 if (fd == AT_FDCWD) { 1386 error = so->so_proto->pr_connect(so, nam, td); 1387 } else { 1388 error = so->so_proto->pr_connectat(fd, so, nam, td); 1389 } 1390 } 1391 CURVNET_RESTORE(); 1392 1393 return (error); 1394 } 1395 1396 int 1397 soconnect2(struct socket *so1, struct socket *so2) 1398 { 1399 int error; 1400 1401 CURVNET_SET(so1->so_vnet); 1402 error = so1->so_proto->pr_connect2(so1, so2); 1403 CURVNET_RESTORE(); 1404 return (error); 1405 } 1406 1407 int 1408 sodisconnect(struct socket *so) 1409 { 1410 int error; 1411 1412 if ((so->so_state & SS_ISCONNECTED) == 0) 1413 return (ENOTCONN); 1414 if (so->so_state & SS_ISDISCONNECTING) 1415 return (EALREADY); 1416 VNET_SO_ASSERT(so); 1417 error = so->so_proto->pr_disconnect(so); 1418 return (error); 1419 } 1420 1421 int 1422 sosend_dgram(struct socket *so, struct sockaddr *addr, struct uio *uio, 1423 struct mbuf *top, struct mbuf *control, int flags, struct thread *td) 1424 { 1425 long space; 1426 ssize_t resid; 1427 int clen = 0, error, dontroute; 1428 1429 KASSERT(so->so_type == SOCK_DGRAM, ("sosend_dgram: !SOCK_DGRAM")); 1430 KASSERT(so->so_proto->pr_flags & PR_ATOMIC, 1431 ("sosend_dgram: !PR_ATOMIC")); 1432 1433 if (uio != NULL) 1434 resid = uio->uio_resid; 1435 else 1436 resid = top->m_pkthdr.len; 1437 /* 1438 * In theory resid should be unsigned. However, space must be 1439 * signed, as it might be less than 0 if we over-committed, and we 1440 * must use a signed comparison of space and resid. On the other 1441 * hand, a negative resid causes us to loop sending 0-length 1442 * segments to the protocol. 1443 */ 1444 if (resid < 0) { 1445 error = EINVAL; 1446 goto out; 1447 } 1448 1449 dontroute = 1450 (flags & MSG_DONTROUTE) && (so->so_options & SO_DONTROUTE) == 0; 1451 if (td != NULL) 1452 td->td_ru.ru_msgsnd++; 1453 if (control != NULL) 1454 clen = control->m_len; 1455 1456 SOCKBUF_LOCK(&so->so_snd); 1457 if (so->so_snd.sb_state & SBS_CANTSENDMORE) { 1458 SOCKBUF_UNLOCK(&so->so_snd); 1459 error = EPIPE; 1460 goto out; 1461 } 1462 if (so->so_error) { 1463 error = so->so_error; 1464 so->so_error = 0; 1465 SOCKBUF_UNLOCK(&so->so_snd); 1466 goto out; 1467 } 1468 if ((so->so_state & SS_ISCONNECTED) == 0) { 1469 /* 1470 * `sendto' and `sendmsg' is allowed on a connection-based 1471 * socket if it supports implied connect. Return ENOTCONN if 1472 * not connected and no address is supplied. 1473 */ 1474 if ((so->so_proto->pr_flags & PR_CONNREQUIRED) && 1475 (so->so_proto->pr_flags & PR_IMPLOPCL) == 0) { 1476 if ((so->so_state & SS_ISCONFIRMING) == 0 && 1477 !(resid == 0 && clen != 0)) { 1478 SOCKBUF_UNLOCK(&so->so_snd); 1479 error = ENOTCONN; 1480 goto out; 1481 } 1482 } else if (addr == NULL) { 1483 if (so->so_proto->pr_flags & PR_CONNREQUIRED) 1484 error = ENOTCONN; 1485 else 1486 error = EDESTADDRREQ; 1487 SOCKBUF_UNLOCK(&so->so_snd); 1488 goto out; 1489 } 1490 } 1491 1492 /* 1493 * Do we need MSG_OOB support in SOCK_DGRAM? Signs here may be a 1494 * problem and need fixing. 1495 */ 1496 space = sbspace(&so->so_snd); 1497 if (flags & MSG_OOB) 1498 space += 1024; 1499 space -= clen; 1500 SOCKBUF_UNLOCK(&so->so_snd); 1501 if (resid > space) { 1502 error = EMSGSIZE; 1503 goto out; 1504 } 1505 if (uio == NULL) { 1506 resid = 0; 1507 if (flags & MSG_EOR) 1508 top->m_flags |= M_EOR; 1509 } else { 1510 /* 1511 * Copy the data from userland into a mbuf chain. 1512 * If no data is to be copied in, a single empty mbuf 1513 * is returned. 1514 */ 1515 top = m_uiotombuf(uio, M_WAITOK, space, max_hdr, 1516 (M_PKTHDR | ((flags & MSG_EOR) ? M_EOR : 0))); 1517 if (top == NULL) { 1518 error = EFAULT; /* only possible error */ 1519 goto out; 1520 } 1521 space -= resid - uio->uio_resid; 1522 resid = uio->uio_resid; 1523 } 1524 KASSERT(resid == 0, ("sosend_dgram: resid != 0")); 1525 /* 1526 * XXXRW: Frobbing SO_DONTROUTE here is even worse without sblock 1527 * than with. 1528 */ 1529 if (dontroute) { 1530 SOCK_LOCK(so); 1531 so->so_options |= SO_DONTROUTE; 1532 SOCK_UNLOCK(so); 1533 } 1534 /* 1535 * XXX all the SBS_CANTSENDMORE checks previously done could be out 1536 * of date. We could have received a reset packet in an interrupt or 1537 * maybe we slept while doing page faults in uiomove() etc. We could 1538 * probably recheck again inside the locking protection here, but 1539 * there are probably other places that this also happens. We must 1540 * rethink this. 1541 */ 1542 VNET_SO_ASSERT(so); 1543 error = so->so_proto->pr_send(so, (flags & MSG_OOB) ? PRUS_OOB : 1544 /* 1545 * If the user set MSG_EOF, the protocol understands this flag and 1546 * nothing left to send then use PRU_SEND_EOF instead of PRU_SEND. 1547 */ 1548 ((flags & MSG_EOF) && 1549 (so->so_proto->pr_flags & PR_IMPLOPCL) && 1550 (resid <= 0)) ? 1551 PRUS_EOF : 1552 /* If there is more to send set PRUS_MORETOCOME */ 1553 (flags & MSG_MORETOCOME) || 1554 (resid > 0 && space > 0) ? PRUS_MORETOCOME : 0, 1555 top, addr, control, td); 1556 if (dontroute) { 1557 SOCK_LOCK(so); 1558 so->so_options &= ~SO_DONTROUTE; 1559 SOCK_UNLOCK(so); 1560 } 1561 clen = 0; 1562 control = NULL; 1563 top = NULL; 1564 out: 1565 if (top != NULL) 1566 m_freem(top); 1567 if (control != NULL) 1568 m_freem(control); 1569 return (error); 1570 } 1571 1572 /* 1573 * Send on a socket. If send must go all at once and message is larger than 1574 * send buffering, then hard error. Lock against other senders. If must go 1575 * all at once and not enough room now, then inform user that this would 1576 * block and do nothing. Otherwise, if nonblocking, send as much as 1577 * possible. The data to be sent is described by "uio" if nonzero, otherwise 1578 * by the mbuf chain "top" (which must be null if uio is not). Data provided 1579 * in mbuf chain must be small enough to send all at once. 1580 * 1581 * Returns nonzero on error, timeout or signal; callers must check for short 1582 * counts if EINTR/ERESTART are returned. Data and control buffers are freed 1583 * on return. 1584 */ 1585 int 1586 sosend_generic(struct socket *so, struct sockaddr *addr, struct uio *uio, 1587 struct mbuf *top, struct mbuf *control, int flags, struct thread *td) 1588 { 1589 long space; 1590 ssize_t resid; 1591 int clen = 0, error, dontroute; 1592 int atomic = sosendallatonce(so) || top; 1593 int pr_send_flag; 1594 #ifdef KERN_TLS 1595 struct ktls_session *tls; 1596 int tls_enq_cnt, tls_send_flag; 1597 uint8_t tls_rtype; 1598 1599 tls = NULL; 1600 tls_rtype = TLS_RLTYPE_APP; 1601 #endif 1602 if (uio != NULL) 1603 resid = uio->uio_resid; 1604 else if ((top->m_flags & M_PKTHDR) != 0) 1605 resid = top->m_pkthdr.len; 1606 else 1607 resid = m_length(top, NULL); 1608 /* 1609 * In theory resid should be unsigned. However, space must be 1610 * signed, as it might be less than 0 if we over-committed, and we 1611 * must use a signed comparison of space and resid. On the other 1612 * hand, a negative resid causes us to loop sending 0-length 1613 * segments to the protocol. 1614 * 1615 * Also check to make sure that MSG_EOR isn't used on SOCK_STREAM 1616 * type sockets since that's an error. 1617 */ 1618 if (resid < 0 || (so->so_type == SOCK_STREAM && (flags & MSG_EOR))) { 1619 error = EINVAL; 1620 goto out; 1621 } 1622 1623 dontroute = 1624 (flags & MSG_DONTROUTE) && (so->so_options & SO_DONTROUTE) == 0 && 1625 (so->so_proto->pr_flags & PR_ATOMIC); 1626 if (td != NULL) 1627 td->td_ru.ru_msgsnd++; 1628 if (control != NULL) 1629 clen = control->m_len; 1630 1631 error = SOCK_IO_SEND_LOCK(so, SBLOCKWAIT(flags)); 1632 if (error) 1633 goto out; 1634 1635 #ifdef KERN_TLS 1636 tls_send_flag = 0; 1637 tls = ktls_hold(so->so_snd.sb_tls_info); 1638 if (tls != NULL) { 1639 if (tls->mode == TCP_TLS_MODE_SW) 1640 tls_send_flag = PRUS_NOTREADY; 1641 1642 if (control != NULL) { 1643 struct cmsghdr *cm = mtod(control, struct cmsghdr *); 1644 1645 if (clen >= sizeof(*cm) && 1646 cm->cmsg_type == TLS_SET_RECORD_TYPE) { 1647 tls_rtype = *((uint8_t *)CMSG_DATA(cm)); 1648 clen = 0; 1649 m_freem(control); 1650 control = NULL; 1651 atomic = 1; 1652 } 1653 } 1654 1655 if (resid == 0 && !ktls_permit_empty_frames(tls)) { 1656 error = EINVAL; 1657 goto release; 1658 } 1659 } 1660 #endif 1661 1662 restart: 1663 do { 1664 SOCKBUF_LOCK(&so->so_snd); 1665 if (so->so_snd.sb_state & SBS_CANTSENDMORE) { 1666 SOCKBUF_UNLOCK(&so->so_snd); 1667 error = EPIPE; 1668 goto release; 1669 } 1670 if (so->so_error) { 1671 error = so->so_error; 1672 so->so_error = 0; 1673 SOCKBUF_UNLOCK(&so->so_snd); 1674 goto release; 1675 } 1676 if ((so->so_state & SS_ISCONNECTED) == 0) { 1677 /* 1678 * `sendto' and `sendmsg' is allowed on a connection- 1679 * based socket if it supports implied connect. 1680 * Return ENOTCONN if not connected and no address is 1681 * supplied. 1682 */ 1683 if ((so->so_proto->pr_flags & PR_CONNREQUIRED) && 1684 (so->so_proto->pr_flags & PR_IMPLOPCL) == 0) { 1685 if ((so->so_state & SS_ISCONFIRMING) == 0 && 1686 !(resid == 0 && clen != 0)) { 1687 SOCKBUF_UNLOCK(&so->so_snd); 1688 error = ENOTCONN; 1689 goto release; 1690 } 1691 } else if (addr == NULL) { 1692 SOCKBUF_UNLOCK(&so->so_snd); 1693 if (so->so_proto->pr_flags & PR_CONNREQUIRED) 1694 error = ENOTCONN; 1695 else 1696 error = EDESTADDRREQ; 1697 goto release; 1698 } 1699 } 1700 space = sbspace(&so->so_snd); 1701 if (flags & MSG_OOB) 1702 space += 1024; 1703 if ((atomic && resid > so->so_snd.sb_hiwat) || 1704 clen > so->so_snd.sb_hiwat) { 1705 SOCKBUF_UNLOCK(&so->so_snd); 1706 error = EMSGSIZE; 1707 goto release; 1708 } 1709 if (space < resid + clen && 1710 (atomic || space < so->so_snd.sb_lowat || space < clen)) { 1711 if ((so->so_state & SS_NBIO) || 1712 (flags & (MSG_NBIO | MSG_DONTWAIT)) != 0) { 1713 SOCKBUF_UNLOCK(&so->so_snd); 1714 error = EWOULDBLOCK; 1715 goto release; 1716 } 1717 error = sbwait(so, SO_SND); 1718 SOCKBUF_UNLOCK(&so->so_snd); 1719 if (error) 1720 goto release; 1721 goto restart; 1722 } 1723 SOCKBUF_UNLOCK(&so->so_snd); 1724 space -= clen; 1725 do { 1726 if (uio == NULL) { 1727 resid = 0; 1728 if (flags & MSG_EOR) 1729 top->m_flags |= M_EOR; 1730 #ifdef KERN_TLS 1731 if (tls != NULL) { 1732 ktls_frame(top, tls, &tls_enq_cnt, 1733 tls_rtype); 1734 tls_rtype = TLS_RLTYPE_APP; 1735 } 1736 #endif 1737 } else { 1738 /* 1739 * Copy the data from userland into a mbuf 1740 * chain. If resid is 0, which can happen 1741 * only if we have control to send, then 1742 * a single empty mbuf is returned. This 1743 * is a workaround to prevent protocol send 1744 * methods to panic. 1745 */ 1746 #ifdef KERN_TLS 1747 if (tls != NULL) { 1748 top = m_uiotombuf(uio, M_WAITOK, space, 1749 tls->params.max_frame_len, 1750 M_EXTPG | 1751 ((flags & MSG_EOR) ? M_EOR : 0)); 1752 if (top != NULL) { 1753 ktls_frame(top, tls, 1754 &tls_enq_cnt, tls_rtype); 1755 } 1756 tls_rtype = TLS_RLTYPE_APP; 1757 } else 1758 #endif 1759 top = m_uiotombuf(uio, M_WAITOK, space, 1760 (atomic ? max_hdr : 0), 1761 (atomic ? M_PKTHDR : 0) | 1762 ((flags & MSG_EOR) ? M_EOR : 0)); 1763 if (top == NULL) { 1764 error = EFAULT; /* only possible error */ 1765 goto release; 1766 } 1767 space -= resid - uio->uio_resid; 1768 resid = uio->uio_resid; 1769 } 1770 if (dontroute) { 1771 SOCK_LOCK(so); 1772 so->so_options |= SO_DONTROUTE; 1773 SOCK_UNLOCK(so); 1774 } 1775 /* 1776 * XXX all the SBS_CANTSENDMORE checks previously 1777 * done could be out of date. We could have received 1778 * a reset packet in an interrupt or maybe we slept 1779 * while doing page faults in uiomove() etc. We 1780 * could probably recheck again inside the locking 1781 * protection here, but there are probably other 1782 * places that this also happens. We must rethink 1783 * this. 1784 */ 1785 VNET_SO_ASSERT(so); 1786 1787 pr_send_flag = (flags & MSG_OOB) ? PRUS_OOB : 1788 /* 1789 * If the user set MSG_EOF, the protocol understands 1790 * this flag and nothing left to send then use 1791 * PRU_SEND_EOF instead of PRU_SEND. 1792 */ 1793 ((flags & MSG_EOF) && 1794 (so->so_proto->pr_flags & PR_IMPLOPCL) && 1795 (resid <= 0)) ? 1796 PRUS_EOF : 1797 /* If there is more to send set PRUS_MORETOCOME. */ 1798 (flags & MSG_MORETOCOME) || 1799 (resid > 0 && space > 0) ? PRUS_MORETOCOME : 0; 1800 1801 #ifdef KERN_TLS 1802 pr_send_flag |= tls_send_flag; 1803 #endif 1804 1805 error = so->so_proto->pr_send(so, pr_send_flag, top, 1806 addr, control, td); 1807 1808 if (dontroute) { 1809 SOCK_LOCK(so); 1810 so->so_options &= ~SO_DONTROUTE; 1811 SOCK_UNLOCK(so); 1812 } 1813 1814 #ifdef KERN_TLS 1815 if (tls != NULL && tls->mode == TCP_TLS_MODE_SW) { 1816 if (error != 0) { 1817 m_freem(top); 1818 top = NULL; 1819 } else { 1820 soref(so); 1821 ktls_enqueue(top, so, tls_enq_cnt); 1822 } 1823 } 1824 #endif 1825 clen = 0; 1826 control = NULL; 1827 top = NULL; 1828 if (error) 1829 goto release; 1830 } while (resid && space > 0); 1831 } while (resid); 1832 1833 release: 1834 SOCK_IO_SEND_UNLOCK(so); 1835 out: 1836 #ifdef KERN_TLS 1837 if (tls != NULL) 1838 ktls_free(tls); 1839 #endif 1840 if (top != NULL) 1841 m_freem(top); 1842 if (control != NULL) 1843 m_freem(control); 1844 return (error); 1845 } 1846 1847 /* 1848 * Send to a socket from a kernel thread. 1849 * 1850 * XXXGL: in almost all cases uio is NULL and the mbuf is supplied. 1851 * Exception is nfs/bootp_subr.c. It is arguable that the VNET context needs 1852 * to be set at all. This function should just boil down to a static inline 1853 * calling the protocol method. 1854 */ 1855 int 1856 sosend(struct socket *so, struct sockaddr *addr, struct uio *uio, 1857 struct mbuf *top, struct mbuf *control, int flags, struct thread *td) 1858 { 1859 int error; 1860 1861 CURVNET_SET(so->so_vnet); 1862 error = so->so_proto->pr_sosend(so, addr, uio, 1863 top, control, flags, td); 1864 CURVNET_RESTORE(); 1865 return (error); 1866 } 1867 1868 /* 1869 * send(2), write(2) or aio_write(2) on a socket. 1870 */ 1871 int 1872 sousrsend(struct socket *so, struct sockaddr *addr, struct uio *uio, 1873 struct mbuf *control, int flags, struct proc *userproc) 1874 { 1875 struct thread *td; 1876 ssize_t len; 1877 int error; 1878 1879 td = uio->uio_td; 1880 len = uio->uio_resid; 1881 CURVNET_SET(so->so_vnet); 1882 error = so->so_proto->pr_sosend(so, addr, uio, NULL, control, flags, 1883 td); 1884 CURVNET_RESTORE(); 1885 if (error != 0) { 1886 /* 1887 * Clear transient errors for stream protocols if they made 1888 * some progress. Make exclusion for aio(4) that would 1889 * schedule a new write in case of EWOULDBLOCK and clear 1890 * error itself. See soaio_process_job(). 1891 */ 1892 if (uio->uio_resid != len && 1893 (so->so_proto->pr_flags & PR_ATOMIC) == 0 && 1894 userproc == NULL && 1895 (error == ERESTART || error == EINTR || 1896 error == EWOULDBLOCK)) 1897 error = 0; 1898 /* Generation of SIGPIPE can be controlled per socket. */ 1899 if (error == EPIPE && (so->so_options & SO_NOSIGPIPE) == 0 && 1900 (flags & MSG_NOSIGNAL) == 0) { 1901 if (userproc != NULL) { 1902 /* aio(4) job */ 1903 PROC_LOCK(userproc); 1904 kern_psignal(userproc, SIGPIPE); 1905 PROC_UNLOCK(userproc); 1906 } else { 1907 PROC_LOCK(td->td_proc); 1908 tdsignal(td, SIGPIPE); 1909 PROC_UNLOCK(td->td_proc); 1910 } 1911 } 1912 } 1913 return (error); 1914 } 1915 1916 /* 1917 * The part of soreceive() that implements reading non-inline out-of-band 1918 * data from a socket. For more complete comments, see soreceive(), from 1919 * which this code originated. 1920 * 1921 * Note that soreceive_rcvoob(), unlike the remainder of soreceive(), is 1922 * unable to return an mbuf chain to the caller. 1923 */ 1924 static int 1925 soreceive_rcvoob(struct socket *so, struct uio *uio, int flags) 1926 { 1927 struct protosw *pr = so->so_proto; 1928 struct mbuf *m; 1929 int error; 1930 1931 KASSERT(flags & MSG_OOB, ("soreceive_rcvoob: (flags & MSG_OOB) == 0")); 1932 VNET_SO_ASSERT(so); 1933 1934 m = m_get(M_WAITOK, MT_DATA); 1935 error = pr->pr_rcvoob(so, m, flags & MSG_PEEK); 1936 if (error) 1937 goto bad; 1938 do { 1939 error = uiomove(mtod(m, void *), 1940 (int) min(uio->uio_resid, m->m_len), uio); 1941 m = m_free(m); 1942 } while (uio->uio_resid && error == 0 && m); 1943 bad: 1944 if (m != NULL) 1945 m_freem(m); 1946 return (error); 1947 } 1948 1949 /* 1950 * Following replacement or removal of the first mbuf on the first mbuf chain 1951 * of a socket buffer, push necessary state changes back into the socket 1952 * buffer so that other consumers see the values consistently. 'nextrecord' 1953 * is the callers locally stored value of the original value of 1954 * sb->sb_mb->m_nextpkt which must be restored when the lead mbuf changes. 1955 * NOTE: 'nextrecord' may be NULL. 1956 */ 1957 static __inline void 1958 sockbuf_pushsync(struct sockbuf *sb, struct mbuf *nextrecord) 1959 { 1960 1961 SOCKBUF_LOCK_ASSERT(sb); 1962 /* 1963 * First, update for the new value of nextrecord. If necessary, make 1964 * it the first record. 1965 */ 1966 if (sb->sb_mb != NULL) 1967 sb->sb_mb->m_nextpkt = nextrecord; 1968 else 1969 sb->sb_mb = nextrecord; 1970 1971 /* 1972 * Now update any dependent socket buffer fields to reflect the new 1973 * state. This is an expanded inline of SB_EMPTY_FIXUP(), with the 1974 * addition of a second clause that takes care of the case where 1975 * sb_mb has been updated, but remains the last record. 1976 */ 1977 if (sb->sb_mb == NULL) { 1978 sb->sb_mbtail = NULL; 1979 sb->sb_lastrecord = NULL; 1980 } else if (sb->sb_mb->m_nextpkt == NULL) 1981 sb->sb_lastrecord = sb->sb_mb; 1982 } 1983 1984 /* 1985 * Implement receive operations on a socket. We depend on the way that 1986 * records are added to the sockbuf by sbappend. In particular, each record 1987 * (mbufs linked through m_next) must begin with an address if the protocol 1988 * so specifies, followed by an optional mbuf or mbufs containing ancillary 1989 * data, and then zero or more mbufs of data. In order to allow parallelism 1990 * between network receive and copying to user space, as well as avoid 1991 * sleeping with a mutex held, we release the socket buffer mutex during the 1992 * user space copy. Although the sockbuf is locked, new data may still be 1993 * appended, and thus we must maintain consistency of the sockbuf during that 1994 * time. 1995 * 1996 * The caller may receive the data as a single mbuf chain by supplying an 1997 * mbuf **mp0 for use in returning the chain. The uio is then used only for 1998 * the count in uio_resid. 1999 */ 2000 int 2001 soreceive_generic(struct socket *so, struct sockaddr **psa, struct uio *uio, 2002 struct mbuf **mp0, struct mbuf **controlp, int *flagsp) 2003 { 2004 struct mbuf *m, **mp; 2005 int flags, error, offset; 2006 ssize_t len; 2007 struct protosw *pr = so->so_proto; 2008 struct mbuf *nextrecord; 2009 int moff, type = 0; 2010 ssize_t orig_resid = uio->uio_resid; 2011 bool report_real_len = false; 2012 2013 mp = mp0; 2014 if (psa != NULL) 2015 *psa = NULL; 2016 if (controlp != NULL) 2017 *controlp = NULL; 2018 if (flagsp != NULL) { 2019 report_real_len = *flagsp & MSG_TRUNC; 2020 *flagsp &= ~MSG_TRUNC; 2021 flags = *flagsp &~ MSG_EOR; 2022 } else 2023 flags = 0; 2024 if (flags & MSG_OOB) 2025 return (soreceive_rcvoob(so, uio, flags)); 2026 if (mp != NULL) 2027 *mp = NULL; 2028 if ((pr->pr_flags & PR_WANTRCVD) && (so->so_state & SS_ISCONFIRMING) 2029 && uio->uio_resid) { 2030 VNET_SO_ASSERT(so); 2031 pr->pr_rcvd(so, 0); 2032 } 2033 2034 error = SOCK_IO_RECV_LOCK(so, SBLOCKWAIT(flags)); 2035 if (error) 2036 return (error); 2037 2038 restart: 2039 SOCKBUF_LOCK(&so->so_rcv); 2040 m = so->so_rcv.sb_mb; 2041 /* 2042 * If we have less data than requested, block awaiting more (subject 2043 * to any timeout) if: 2044 * 1. the current count is less than the low water mark, or 2045 * 2. MSG_DONTWAIT is not set 2046 */ 2047 if (m == NULL || (((flags & MSG_DONTWAIT) == 0 && 2048 sbavail(&so->so_rcv) < uio->uio_resid) && 2049 sbavail(&so->so_rcv) < so->so_rcv.sb_lowat && 2050 m->m_nextpkt == NULL && (pr->pr_flags & PR_ATOMIC) == 0)) { 2051 KASSERT(m != NULL || !sbavail(&so->so_rcv), 2052 ("receive: m == %p sbavail == %u", 2053 m, sbavail(&so->so_rcv))); 2054 if (so->so_error || so->so_rerror) { 2055 if (m != NULL) 2056 goto dontblock; 2057 if (so->so_error) 2058 error = so->so_error; 2059 else 2060 error = so->so_rerror; 2061 if ((flags & MSG_PEEK) == 0) { 2062 if (so->so_error) 2063 so->so_error = 0; 2064 else 2065 so->so_rerror = 0; 2066 } 2067 SOCKBUF_UNLOCK(&so->so_rcv); 2068 goto release; 2069 } 2070 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 2071 if (so->so_rcv.sb_state & SBS_CANTRCVMORE) { 2072 if (m != NULL) 2073 goto dontblock; 2074 #ifdef KERN_TLS 2075 else if (so->so_rcv.sb_tlsdcc == 0 && 2076 so->so_rcv.sb_tlscc == 0) { 2077 #else 2078 else { 2079 #endif 2080 SOCKBUF_UNLOCK(&so->so_rcv); 2081 goto release; 2082 } 2083 } 2084 for (; m != NULL; m = m->m_next) 2085 if (m->m_type == MT_OOBDATA || (m->m_flags & M_EOR)) { 2086 m = so->so_rcv.sb_mb; 2087 goto dontblock; 2088 } 2089 if ((so->so_state & (SS_ISCONNECTING | SS_ISCONNECTED | 2090 SS_ISDISCONNECTING | SS_ISDISCONNECTED)) == 0 && 2091 (so->so_proto->pr_flags & PR_CONNREQUIRED) != 0) { 2092 SOCKBUF_UNLOCK(&so->so_rcv); 2093 error = ENOTCONN; 2094 goto release; 2095 } 2096 if (uio->uio_resid == 0 && !report_real_len) { 2097 SOCKBUF_UNLOCK(&so->so_rcv); 2098 goto release; 2099 } 2100 if ((so->so_state & SS_NBIO) || 2101 (flags & (MSG_DONTWAIT|MSG_NBIO))) { 2102 SOCKBUF_UNLOCK(&so->so_rcv); 2103 error = EWOULDBLOCK; 2104 goto release; 2105 } 2106 SBLASTRECORDCHK(&so->so_rcv); 2107 SBLASTMBUFCHK(&so->so_rcv); 2108 error = sbwait(so, SO_RCV); 2109 SOCKBUF_UNLOCK(&so->so_rcv); 2110 if (error) 2111 goto release; 2112 goto restart; 2113 } 2114 dontblock: 2115 /* 2116 * From this point onward, we maintain 'nextrecord' as a cache of the 2117 * pointer to the next record in the socket buffer. We must keep the 2118 * various socket buffer pointers and local stack versions of the 2119 * pointers in sync, pushing out modifications before dropping the 2120 * socket buffer mutex, and re-reading them when picking it up. 2121 * 2122 * Otherwise, we will race with the network stack appending new data 2123 * or records onto the socket buffer by using inconsistent/stale 2124 * versions of the field, possibly resulting in socket buffer 2125 * corruption. 2126 * 2127 * By holding the high-level sblock(), we prevent simultaneous 2128 * readers from pulling off the front of the socket buffer. 2129 */ 2130 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 2131 if (uio->uio_td) 2132 uio->uio_td->td_ru.ru_msgrcv++; 2133 KASSERT(m == so->so_rcv.sb_mb, ("soreceive: m != so->so_rcv.sb_mb")); 2134 SBLASTRECORDCHK(&so->so_rcv); 2135 SBLASTMBUFCHK(&so->so_rcv); 2136 nextrecord = m->m_nextpkt; 2137 if (pr->pr_flags & PR_ADDR) { 2138 KASSERT(m->m_type == MT_SONAME, 2139 ("m->m_type == %d", m->m_type)); 2140 orig_resid = 0; 2141 if (psa != NULL) 2142 *psa = sodupsockaddr(mtod(m, struct sockaddr *), 2143 M_NOWAIT); 2144 if (flags & MSG_PEEK) { 2145 m = m->m_next; 2146 } else { 2147 sbfree(&so->so_rcv, m); 2148 so->so_rcv.sb_mb = m_free(m); 2149 m = so->so_rcv.sb_mb; 2150 sockbuf_pushsync(&so->so_rcv, nextrecord); 2151 } 2152 } 2153 2154 /* 2155 * Process one or more MT_CONTROL mbufs present before any data mbufs 2156 * in the first mbuf chain on the socket buffer. If MSG_PEEK, we 2157 * just copy the data; if !MSG_PEEK, we call into the protocol to 2158 * perform externalization (or freeing if controlp == NULL). 2159 */ 2160 if (m != NULL && m->m_type == MT_CONTROL) { 2161 struct mbuf *cm = NULL, *cmn; 2162 struct mbuf **cme = &cm; 2163 #ifdef KERN_TLS 2164 struct cmsghdr *cmsg; 2165 struct tls_get_record tgr; 2166 2167 /* 2168 * For MSG_TLSAPPDATA, check for an alert record. 2169 * If found, return ENXIO without removing 2170 * it from the receive queue. This allows a subsequent 2171 * call without MSG_TLSAPPDATA to receive it. 2172 * Note that, for TLS, there should only be a single 2173 * control mbuf with the TLS_GET_RECORD message in it. 2174 */ 2175 if (flags & MSG_TLSAPPDATA) { 2176 cmsg = mtod(m, struct cmsghdr *); 2177 if (cmsg->cmsg_type == TLS_GET_RECORD && 2178 cmsg->cmsg_len == CMSG_LEN(sizeof(tgr))) { 2179 memcpy(&tgr, CMSG_DATA(cmsg), sizeof(tgr)); 2180 if (__predict_false(tgr.tls_type == 2181 TLS_RLTYPE_ALERT)) { 2182 SOCKBUF_UNLOCK(&so->so_rcv); 2183 error = ENXIO; 2184 goto release; 2185 } 2186 } 2187 } 2188 #endif 2189 2190 do { 2191 if (flags & MSG_PEEK) { 2192 if (controlp != NULL) { 2193 *controlp = m_copym(m, 0, m->m_len, 2194 M_NOWAIT); 2195 controlp = &(*controlp)->m_next; 2196 } 2197 m = m->m_next; 2198 } else { 2199 sbfree(&so->so_rcv, m); 2200 so->so_rcv.sb_mb = m->m_next; 2201 m->m_next = NULL; 2202 *cme = m; 2203 cme = &(*cme)->m_next; 2204 m = so->so_rcv.sb_mb; 2205 } 2206 } while (m != NULL && m->m_type == MT_CONTROL); 2207 if ((flags & MSG_PEEK) == 0) 2208 sockbuf_pushsync(&so->so_rcv, nextrecord); 2209 while (cm != NULL) { 2210 cmn = cm->m_next; 2211 cm->m_next = NULL; 2212 if (pr->pr_domain->dom_externalize != NULL) { 2213 SOCKBUF_UNLOCK(&so->so_rcv); 2214 VNET_SO_ASSERT(so); 2215 error = (*pr->pr_domain->dom_externalize) 2216 (cm, controlp, flags); 2217 SOCKBUF_LOCK(&so->so_rcv); 2218 } else if (controlp != NULL) 2219 *controlp = cm; 2220 else 2221 m_freem(cm); 2222 if (controlp != NULL) { 2223 while (*controlp != NULL) 2224 controlp = &(*controlp)->m_next; 2225 } 2226 cm = cmn; 2227 } 2228 if (m != NULL) 2229 nextrecord = so->so_rcv.sb_mb->m_nextpkt; 2230 else 2231 nextrecord = so->so_rcv.sb_mb; 2232 orig_resid = 0; 2233 } 2234 if (m != NULL) { 2235 if ((flags & MSG_PEEK) == 0) { 2236 KASSERT(m->m_nextpkt == nextrecord, 2237 ("soreceive: post-control, nextrecord !sync")); 2238 if (nextrecord == NULL) { 2239 KASSERT(so->so_rcv.sb_mb == m, 2240 ("soreceive: post-control, sb_mb!=m")); 2241 KASSERT(so->so_rcv.sb_lastrecord == m, 2242 ("soreceive: post-control, lastrecord!=m")); 2243 } 2244 } 2245 type = m->m_type; 2246 if (type == MT_OOBDATA) 2247 flags |= MSG_OOB; 2248 } else { 2249 if ((flags & MSG_PEEK) == 0) { 2250 KASSERT(so->so_rcv.sb_mb == nextrecord, 2251 ("soreceive: sb_mb != nextrecord")); 2252 if (so->so_rcv.sb_mb == NULL) { 2253 KASSERT(so->so_rcv.sb_lastrecord == NULL, 2254 ("soreceive: sb_lastercord != NULL")); 2255 } 2256 } 2257 } 2258 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 2259 SBLASTRECORDCHK(&so->so_rcv); 2260 SBLASTMBUFCHK(&so->so_rcv); 2261 2262 /* 2263 * Now continue to read any data mbufs off of the head of the socket 2264 * buffer until the read request is satisfied. Note that 'type' is 2265 * used to store the type of any mbuf reads that have happened so far 2266 * such that soreceive() can stop reading if the type changes, which 2267 * causes soreceive() to return only one of regular data and inline 2268 * out-of-band data in a single socket receive operation. 2269 */ 2270 moff = 0; 2271 offset = 0; 2272 while (m != NULL && !(m->m_flags & M_NOTAVAIL) && uio->uio_resid > 0 2273 && error == 0) { 2274 /* 2275 * If the type of mbuf has changed since the last mbuf 2276 * examined ('type'), end the receive operation. 2277 */ 2278 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 2279 if (m->m_type == MT_OOBDATA || m->m_type == MT_CONTROL) { 2280 if (type != m->m_type) 2281 break; 2282 } else if (type == MT_OOBDATA) 2283 break; 2284 else 2285 KASSERT(m->m_type == MT_DATA, 2286 ("m->m_type == %d", m->m_type)); 2287 so->so_rcv.sb_state &= ~SBS_RCVATMARK; 2288 len = uio->uio_resid; 2289 if (so->so_oobmark && len > so->so_oobmark - offset) 2290 len = so->so_oobmark - offset; 2291 if (len > m->m_len - moff) 2292 len = m->m_len - moff; 2293 /* 2294 * If mp is set, just pass back the mbufs. Otherwise copy 2295 * them out via the uio, then free. Sockbuf must be 2296 * consistent here (points to current mbuf, it points to next 2297 * record) when we drop priority; we must note any additions 2298 * to the sockbuf when we block interrupts again. 2299 */ 2300 if (mp == NULL) { 2301 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 2302 SBLASTRECORDCHK(&so->so_rcv); 2303 SBLASTMBUFCHK(&so->so_rcv); 2304 SOCKBUF_UNLOCK(&so->so_rcv); 2305 if ((m->m_flags & M_EXTPG) != 0) 2306 error = m_unmapped_uiomove(m, moff, uio, 2307 (int)len); 2308 else 2309 error = uiomove(mtod(m, char *) + moff, 2310 (int)len, uio); 2311 SOCKBUF_LOCK(&so->so_rcv); 2312 if (error) { 2313 /* 2314 * The MT_SONAME mbuf has already been removed 2315 * from the record, so it is necessary to 2316 * remove the data mbufs, if any, to preserve 2317 * the invariant in the case of PR_ADDR that 2318 * requires MT_SONAME mbufs at the head of 2319 * each record. 2320 */ 2321 if (pr->pr_flags & PR_ATOMIC && 2322 ((flags & MSG_PEEK) == 0)) 2323 (void)sbdroprecord_locked(&so->so_rcv); 2324 SOCKBUF_UNLOCK(&so->so_rcv); 2325 goto release; 2326 } 2327 } else 2328 uio->uio_resid -= len; 2329 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 2330 if (len == m->m_len - moff) { 2331 if (m->m_flags & M_EOR) 2332 flags |= MSG_EOR; 2333 if (flags & MSG_PEEK) { 2334 m = m->m_next; 2335 moff = 0; 2336 } else { 2337 nextrecord = m->m_nextpkt; 2338 sbfree(&so->so_rcv, m); 2339 if (mp != NULL) { 2340 m->m_nextpkt = NULL; 2341 *mp = m; 2342 mp = &m->m_next; 2343 so->so_rcv.sb_mb = m = m->m_next; 2344 *mp = NULL; 2345 } else { 2346 so->so_rcv.sb_mb = m_free(m); 2347 m = so->so_rcv.sb_mb; 2348 } 2349 sockbuf_pushsync(&so->so_rcv, nextrecord); 2350 SBLASTRECORDCHK(&so->so_rcv); 2351 SBLASTMBUFCHK(&so->so_rcv); 2352 } 2353 } else { 2354 if (flags & MSG_PEEK) 2355 moff += len; 2356 else { 2357 if (mp != NULL) { 2358 if (flags & MSG_DONTWAIT) { 2359 *mp = m_copym(m, 0, len, 2360 M_NOWAIT); 2361 if (*mp == NULL) { 2362 /* 2363 * m_copym() couldn't 2364 * allocate an mbuf. 2365 * Adjust uio_resid back 2366 * (it was adjusted 2367 * down by len bytes, 2368 * which we didn't end 2369 * up "copying" over). 2370 */ 2371 uio->uio_resid += len; 2372 break; 2373 } 2374 } else { 2375 SOCKBUF_UNLOCK(&so->so_rcv); 2376 *mp = m_copym(m, 0, len, 2377 M_WAITOK); 2378 SOCKBUF_LOCK(&so->so_rcv); 2379 } 2380 } 2381 sbcut_locked(&so->so_rcv, len); 2382 } 2383 } 2384 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 2385 if (so->so_oobmark) { 2386 if ((flags & MSG_PEEK) == 0) { 2387 so->so_oobmark -= len; 2388 if (so->so_oobmark == 0) { 2389 so->so_rcv.sb_state |= SBS_RCVATMARK; 2390 break; 2391 } 2392 } else { 2393 offset += len; 2394 if (offset == so->so_oobmark) 2395 break; 2396 } 2397 } 2398 if (flags & MSG_EOR) 2399 break; 2400 /* 2401 * If the MSG_WAITALL flag is set (for non-atomic socket), we 2402 * must not quit until "uio->uio_resid == 0" or an error 2403 * termination. If a signal/timeout occurs, return with a 2404 * short count but without error. Keep sockbuf locked 2405 * against other readers. 2406 */ 2407 while (flags & MSG_WAITALL && m == NULL && uio->uio_resid > 0 && 2408 !sosendallatonce(so) && nextrecord == NULL) { 2409 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 2410 if (so->so_error || so->so_rerror || 2411 so->so_rcv.sb_state & SBS_CANTRCVMORE) 2412 break; 2413 /* 2414 * Notify the protocol that some data has been 2415 * drained before blocking. 2416 */ 2417 if (pr->pr_flags & PR_WANTRCVD) { 2418 SOCKBUF_UNLOCK(&so->so_rcv); 2419 VNET_SO_ASSERT(so); 2420 pr->pr_rcvd(so, flags); 2421 SOCKBUF_LOCK(&so->so_rcv); 2422 } 2423 SBLASTRECORDCHK(&so->so_rcv); 2424 SBLASTMBUFCHK(&so->so_rcv); 2425 /* 2426 * We could receive some data while was notifying 2427 * the protocol. Skip blocking in this case. 2428 */ 2429 if (so->so_rcv.sb_mb == NULL) { 2430 error = sbwait(so, SO_RCV); 2431 if (error) { 2432 SOCKBUF_UNLOCK(&so->so_rcv); 2433 goto release; 2434 } 2435 } 2436 m = so->so_rcv.sb_mb; 2437 if (m != NULL) 2438 nextrecord = m->m_nextpkt; 2439 } 2440 } 2441 2442 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 2443 if (m != NULL && pr->pr_flags & PR_ATOMIC) { 2444 if (report_real_len) 2445 uio->uio_resid -= m_length(m, NULL) - moff; 2446 flags |= MSG_TRUNC; 2447 if ((flags & MSG_PEEK) == 0) 2448 (void) sbdroprecord_locked(&so->so_rcv); 2449 } 2450 if ((flags & MSG_PEEK) == 0) { 2451 if (m == NULL) { 2452 /* 2453 * First part is an inline SB_EMPTY_FIXUP(). Second 2454 * part makes sure sb_lastrecord is up-to-date if 2455 * there is still data in the socket buffer. 2456 */ 2457 so->so_rcv.sb_mb = nextrecord; 2458 if (so->so_rcv.sb_mb == NULL) { 2459 so->so_rcv.sb_mbtail = NULL; 2460 so->so_rcv.sb_lastrecord = NULL; 2461 } else if (nextrecord->m_nextpkt == NULL) 2462 so->so_rcv.sb_lastrecord = nextrecord; 2463 } 2464 SBLASTRECORDCHK(&so->so_rcv); 2465 SBLASTMBUFCHK(&so->so_rcv); 2466 /* 2467 * If soreceive() is being done from the socket callback, 2468 * then don't need to generate ACK to peer to update window, 2469 * since ACK will be generated on return to TCP. 2470 */ 2471 if (!(flags & MSG_SOCALLBCK) && 2472 (pr->pr_flags & PR_WANTRCVD)) { 2473 SOCKBUF_UNLOCK(&so->so_rcv); 2474 VNET_SO_ASSERT(so); 2475 pr->pr_rcvd(so, flags); 2476 SOCKBUF_LOCK(&so->so_rcv); 2477 } 2478 } 2479 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 2480 if (orig_resid == uio->uio_resid && orig_resid && 2481 (flags & MSG_EOR) == 0 && (so->so_rcv.sb_state & SBS_CANTRCVMORE) == 0) { 2482 SOCKBUF_UNLOCK(&so->so_rcv); 2483 goto restart; 2484 } 2485 SOCKBUF_UNLOCK(&so->so_rcv); 2486 2487 if (flagsp != NULL) 2488 *flagsp |= flags; 2489 release: 2490 SOCK_IO_RECV_UNLOCK(so); 2491 return (error); 2492 } 2493 2494 /* 2495 * Optimized version of soreceive() for stream (TCP) sockets. 2496 */ 2497 int 2498 soreceive_stream(struct socket *so, struct sockaddr **psa, struct uio *uio, 2499 struct mbuf **mp0, struct mbuf **controlp, int *flagsp) 2500 { 2501 int len = 0, error = 0, flags, oresid; 2502 struct sockbuf *sb; 2503 struct mbuf *m, *n = NULL; 2504 2505 /* We only do stream sockets. */ 2506 if (so->so_type != SOCK_STREAM) 2507 return (EINVAL); 2508 if (psa != NULL) 2509 *psa = NULL; 2510 if (flagsp != NULL) 2511 flags = *flagsp &~ MSG_EOR; 2512 else 2513 flags = 0; 2514 if (controlp != NULL) 2515 *controlp = NULL; 2516 if (flags & MSG_OOB) 2517 return (soreceive_rcvoob(so, uio, flags)); 2518 if (mp0 != NULL) 2519 *mp0 = NULL; 2520 2521 sb = &so->so_rcv; 2522 2523 #ifdef KERN_TLS 2524 /* 2525 * KTLS store TLS records as records with a control message to 2526 * describe the framing. 2527 * 2528 * We check once here before acquiring locks to optimize the 2529 * common case. 2530 */ 2531 if (sb->sb_tls_info != NULL) 2532 return (soreceive_generic(so, psa, uio, mp0, controlp, 2533 flagsp)); 2534 #endif 2535 2536 /* Prevent other readers from entering the socket. */ 2537 error = SOCK_IO_RECV_LOCK(so, SBLOCKWAIT(flags)); 2538 if (error) 2539 return (error); 2540 SOCKBUF_LOCK(sb); 2541 2542 #ifdef KERN_TLS 2543 if (sb->sb_tls_info != NULL) { 2544 SOCKBUF_UNLOCK(sb); 2545 SOCK_IO_RECV_UNLOCK(so); 2546 return (soreceive_generic(so, psa, uio, mp0, controlp, 2547 flagsp)); 2548 } 2549 #endif 2550 2551 /* Easy one, no space to copyout anything. */ 2552 if (uio->uio_resid == 0) { 2553 error = EINVAL; 2554 goto out; 2555 } 2556 oresid = uio->uio_resid; 2557 2558 /* We will never ever get anything unless we are or were connected. */ 2559 if (!(so->so_state & (SS_ISCONNECTED|SS_ISDISCONNECTED))) { 2560 error = ENOTCONN; 2561 goto out; 2562 } 2563 2564 restart: 2565 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 2566 2567 /* Abort if socket has reported problems. */ 2568 if (so->so_error) { 2569 if (sbavail(sb) > 0) 2570 goto deliver; 2571 if (oresid > uio->uio_resid) 2572 goto out; 2573 error = so->so_error; 2574 if (!(flags & MSG_PEEK)) 2575 so->so_error = 0; 2576 goto out; 2577 } 2578 2579 /* Door is closed. Deliver what is left, if any. */ 2580 if (sb->sb_state & SBS_CANTRCVMORE) { 2581 if (sbavail(sb) > 0) 2582 goto deliver; 2583 else 2584 goto out; 2585 } 2586 2587 /* Socket buffer is empty and we shall not block. */ 2588 if (sbavail(sb) == 0 && 2589 ((so->so_state & SS_NBIO) || (flags & (MSG_DONTWAIT|MSG_NBIO)))) { 2590 error = EAGAIN; 2591 goto out; 2592 } 2593 2594 /* Socket buffer got some data that we shall deliver now. */ 2595 if (sbavail(sb) > 0 && !(flags & MSG_WAITALL) && 2596 ((so->so_state & SS_NBIO) || 2597 (flags & (MSG_DONTWAIT|MSG_NBIO)) || 2598 sbavail(sb) >= sb->sb_lowat || 2599 sbavail(sb) >= uio->uio_resid || 2600 sbavail(sb) >= sb->sb_hiwat) ) { 2601 goto deliver; 2602 } 2603 2604 /* On MSG_WAITALL we must wait until all data or error arrives. */ 2605 if ((flags & MSG_WAITALL) && 2606 (sbavail(sb) >= uio->uio_resid || sbavail(sb) >= sb->sb_hiwat)) 2607 goto deliver; 2608 2609 /* 2610 * Wait and block until (more) data comes in. 2611 * NB: Drops the sockbuf lock during wait. 2612 */ 2613 error = sbwait(so, SO_RCV); 2614 if (error) 2615 goto out; 2616 goto restart; 2617 2618 deliver: 2619 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 2620 KASSERT(sbavail(sb) > 0, ("%s: sockbuf empty", __func__)); 2621 KASSERT(sb->sb_mb != NULL, ("%s: sb_mb == NULL", __func__)); 2622 2623 /* Statistics. */ 2624 if (uio->uio_td) 2625 uio->uio_td->td_ru.ru_msgrcv++; 2626 2627 /* Fill uio until full or current end of socket buffer is reached. */ 2628 len = min(uio->uio_resid, sbavail(sb)); 2629 if (mp0 != NULL) { 2630 /* Dequeue as many mbufs as possible. */ 2631 if (!(flags & MSG_PEEK) && len >= sb->sb_mb->m_len) { 2632 if (*mp0 == NULL) 2633 *mp0 = sb->sb_mb; 2634 else 2635 m_cat(*mp0, sb->sb_mb); 2636 for (m = sb->sb_mb; 2637 m != NULL && m->m_len <= len; 2638 m = m->m_next) { 2639 KASSERT(!(m->m_flags & M_NOTAVAIL), 2640 ("%s: m %p not available", __func__, m)); 2641 len -= m->m_len; 2642 uio->uio_resid -= m->m_len; 2643 sbfree(sb, m); 2644 n = m; 2645 } 2646 n->m_next = NULL; 2647 sb->sb_mb = m; 2648 sb->sb_lastrecord = sb->sb_mb; 2649 if (sb->sb_mb == NULL) 2650 SB_EMPTY_FIXUP(sb); 2651 } 2652 /* Copy the remainder. */ 2653 if (len > 0) { 2654 KASSERT(sb->sb_mb != NULL, 2655 ("%s: len > 0 && sb->sb_mb empty", __func__)); 2656 2657 m = m_copym(sb->sb_mb, 0, len, M_NOWAIT); 2658 if (m == NULL) 2659 len = 0; /* Don't flush data from sockbuf. */ 2660 else 2661 uio->uio_resid -= len; 2662 if (*mp0 != NULL) 2663 m_cat(*mp0, m); 2664 else 2665 *mp0 = m; 2666 if (*mp0 == NULL) { 2667 error = ENOBUFS; 2668 goto out; 2669 } 2670 } 2671 } else { 2672 /* NB: Must unlock socket buffer as uiomove may sleep. */ 2673 SOCKBUF_UNLOCK(sb); 2674 error = m_mbuftouio(uio, sb->sb_mb, len); 2675 SOCKBUF_LOCK(sb); 2676 if (error) 2677 goto out; 2678 } 2679 SBLASTRECORDCHK(sb); 2680 SBLASTMBUFCHK(sb); 2681 2682 /* 2683 * Remove the delivered data from the socket buffer unless we 2684 * were only peeking. 2685 */ 2686 if (!(flags & MSG_PEEK)) { 2687 if (len > 0) 2688 sbdrop_locked(sb, len); 2689 2690 /* Notify protocol that we drained some data. */ 2691 if ((so->so_proto->pr_flags & PR_WANTRCVD) && 2692 (((flags & MSG_WAITALL) && uio->uio_resid > 0) || 2693 !(flags & MSG_SOCALLBCK))) { 2694 SOCKBUF_UNLOCK(sb); 2695 VNET_SO_ASSERT(so); 2696 so->so_proto->pr_rcvd(so, flags); 2697 SOCKBUF_LOCK(sb); 2698 } 2699 } 2700 2701 /* 2702 * For MSG_WAITALL we may have to loop again and wait for 2703 * more data to come in. 2704 */ 2705 if ((flags & MSG_WAITALL) && uio->uio_resid > 0) 2706 goto restart; 2707 out: 2708 SBLASTRECORDCHK(sb); 2709 SBLASTMBUFCHK(sb); 2710 SOCKBUF_UNLOCK(sb); 2711 SOCK_IO_RECV_UNLOCK(so); 2712 return (error); 2713 } 2714 2715 /* 2716 * Optimized version of soreceive() for simple datagram cases from userspace. 2717 * Unlike in the stream case, we're able to drop a datagram if copyout() 2718 * fails, and because we handle datagrams atomically, we don't need to use a 2719 * sleep lock to prevent I/O interlacing. 2720 */ 2721 int 2722 soreceive_dgram(struct socket *so, struct sockaddr **psa, struct uio *uio, 2723 struct mbuf **mp0, struct mbuf **controlp, int *flagsp) 2724 { 2725 struct mbuf *m, *m2; 2726 int flags, error; 2727 ssize_t len; 2728 struct protosw *pr = so->so_proto; 2729 struct mbuf *nextrecord; 2730 2731 if (psa != NULL) 2732 *psa = NULL; 2733 if (controlp != NULL) 2734 *controlp = NULL; 2735 if (flagsp != NULL) 2736 flags = *flagsp &~ MSG_EOR; 2737 else 2738 flags = 0; 2739 2740 /* 2741 * For any complicated cases, fall back to the full 2742 * soreceive_generic(). 2743 */ 2744 if (mp0 != NULL || (flags & (MSG_PEEK | MSG_OOB | MSG_TRUNC))) 2745 return (soreceive_generic(so, psa, uio, mp0, controlp, 2746 flagsp)); 2747 2748 /* 2749 * Enforce restrictions on use. 2750 */ 2751 KASSERT((pr->pr_flags & PR_WANTRCVD) == 0, 2752 ("soreceive_dgram: wantrcvd")); 2753 KASSERT(pr->pr_flags & PR_ATOMIC, ("soreceive_dgram: !atomic")); 2754 KASSERT((so->so_rcv.sb_state & SBS_RCVATMARK) == 0, 2755 ("soreceive_dgram: SBS_RCVATMARK")); 2756 KASSERT((so->so_proto->pr_flags & PR_CONNREQUIRED) == 0, 2757 ("soreceive_dgram: P_CONNREQUIRED")); 2758 2759 /* 2760 * Loop blocking while waiting for a datagram. 2761 */ 2762 SOCKBUF_LOCK(&so->so_rcv); 2763 while ((m = so->so_rcv.sb_mb) == NULL) { 2764 KASSERT(sbavail(&so->so_rcv) == 0, 2765 ("soreceive_dgram: sb_mb NULL but sbavail %u", 2766 sbavail(&so->so_rcv))); 2767 if (so->so_error) { 2768 error = so->so_error; 2769 so->so_error = 0; 2770 SOCKBUF_UNLOCK(&so->so_rcv); 2771 return (error); 2772 } 2773 if (so->so_rcv.sb_state & SBS_CANTRCVMORE || 2774 uio->uio_resid == 0) { 2775 SOCKBUF_UNLOCK(&so->so_rcv); 2776 return (0); 2777 } 2778 if ((so->so_state & SS_NBIO) || 2779 (flags & (MSG_DONTWAIT|MSG_NBIO))) { 2780 SOCKBUF_UNLOCK(&so->so_rcv); 2781 return (EWOULDBLOCK); 2782 } 2783 SBLASTRECORDCHK(&so->so_rcv); 2784 SBLASTMBUFCHK(&so->so_rcv); 2785 error = sbwait(so, SO_RCV); 2786 if (error) { 2787 SOCKBUF_UNLOCK(&so->so_rcv); 2788 return (error); 2789 } 2790 } 2791 SOCKBUF_LOCK_ASSERT(&so->so_rcv); 2792 2793 if (uio->uio_td) 2794 uio->uio_td->td_ru.ru_msgrcv++; 2795 SBLASTRECORDCHK(&so->so_rcv); 2796 SBLASTMBUFCHK(&so->so_rcv); 2797 nextrecord = m->m_nextpkt; 2798 if (nextrecord == NULL) { 2799 KASSERT(so->so_rcv.sb_lastrecord == m, 2800 ("soreceive_dgram: lastrecord != m")); 2801 } 2802 2803 KASSERT(so->so_rcv.sb_mb->m_nextpkt == nextrecord, 2804 ("soreceive_dgram: m_nextpkt != nextrecord")); 2805 2806 /* 2807 * Pull 'm' and its chain off the front of the packet queue. 2808 */ 2809 so->so_rcv.sb_mb = NULL; 2810 sockbuf_pushsync(&so->so_rcv, nextrecord); 2811 2812 /* 2813 * Walk 'm's chain and free that many bytes from the socket buffer. 2814 */ 2815 for (m2 = m; m2 != NULL; m2 = m2->m_next) 2816 sbfree(&so->so_rcv, m2); 2817 2818 /* 2819 * Do a few last checks before we let go of the lock. 2820 */ 2821 SBLASTRECORDCHK(&so->so_rcv); 2822 SBLASTMBUFCHK(&so->so_rcv); 2823 SOCKBUF_UNLOCK(&so->so_rcv); 2824 2825 if (pr->pr_flags & PR_ADDR) { 2826 KASSERT(m->m_type == MT_SONAME, 2827 ("m->m_type == %d", m->m_type)); 2828 if (psa != NULL) 2829 *psa = sodupsockaddr(mtod(m, struct sockaddr *), 2830 M_NOWAIT); 2831 m = m_free(m); 2832 } 2833 if (m == NULL) { 2834 /* XXXRW: Can this happen? */ 2835 return (0); 2836 } 2837 2838 /* 2839 * Packet to copyout() is now in 'm' and it is disconnected from the 2840 * queue. 2841 * 2842 * Process one or more MT_CONTROL mbufs present before any data mbufs 2843 * in the first mbuf chain on the socket buffer. We call into the 2844 * protocol to perform externalization (or freeing if controlp == 2845 * NULL). In some cases there can be only MT_CONTROL mbufs without 2846 * MT_DATA mbufs. 2847 */ 2848 if (m->m_type == MT_CONTROL) { 2849 struct mbuf *cm = NULL, *cmn; 2850 struct mbuf **cme = &cm; 2851 2852 do { 2853 m2 = m->m_next; 2854 m->m_next = NULL; 2855 *cme = m; 2856 cme = &(*cme)->m_next; 2857 m = m2; 2858 } while (m != NULL && m->m_type == MT_CONTROL); 2859 while (cm != NULL) { 2860 cmn = cm->m_next; 2861 cm->m_next = NULL; 2862 if (pr->pr_domain->dom_externalize != NULL) { 2863 error = (*pr->pr_domain->dom_externalize) 2864 (cm, controlp, flags); 2865 } else if (controlp != NULL) 2866 *controlp = cm; 2867 else 2868 m_freem(cm); 2869 if (controlp != NULL) { 2870 while (*controlp != NULL) 2871 controlp = &(*controlp)->m_next; 2872 } 2873 cm = cmn; 2874 } 2875 } 2876 KASSERT(m == NULL || m->m_type == MT_DATA, 2877 ("soreceive_dgram: !data")); 2878 while (m != NULL && uio->uio_resid > 0) { 2879 len = uio->uio_resid; 2880 if (len > m->m_len) 2881 len = m->m_len; 2882 error = uiomove(mtod(m, char *), (int)len, uio); 2883 if (error) { 2884 m_freem(m); 2885 return (error); 2886 } 2887 if (len == m->m_len) 2888 m = m_free(m); 2889 else { 2890 m->m_data += len; 2891 m->m_len -= len; 2892 } 2893 } 2894 if (m != NULL) { 2895 flags |= MSG_TRUNC; 2896 m_freem(m); 2897 } 2898 if (flagsp != NULL) 2899 *flagsp |= flags; 2900 return (0); 2901 } 2902 2903 int 2904 soreceive(struct socket *so, struct sockaddr **psa, struct uio *uio, 2905 struct mbuf **mp0, struct mbuf **controlp, int *flagsp) 2906 { 2907 int error; 2908 2909 CURVNET_SET(so->so_vnet); 2910 error = so->so_proto->pr_soreceive(so, psa, uio, mp0, controlp, flagsp); 2911 CURVNET_RESTORE(); 2912 return (error); 2913 } 2914 2915 int 2916 soshutdown(struct socket *so, int how) 2917 { 2918 struct protosw *pr; 2919 int error, soerror_enotconn; 2920 2921 if (!(how == SHUT_RD || how == SHUT_WR || how == SHUT_RDWR)) 2922 return (EINVAL); 2923 2924 soerror_enotconn = 0; 2925 SOCK_LOCK(so); 2926 if ((so->so_state & 2927 (SS_ISCONNECTED | SS_ISCONNECTING | SS_ISDISCONNECTING)) == 0) { 2928 /* 2929 * POSIX mandates us to return ENOTCONN when shutdown(2) is 2930 * invoked on a datagram sockets, however historically we would 2931 * actually tear socket down. This is known to be leveraged by 2932 * some applications to unblock process waiting in recvXXX(2) 2933 * by other process that it shares that socket with. Try to meet 2934 * both backward-compatibility and POSIX requirements by forcing 2935 * ENOTCONN but still asking protocol to perform pru_shutdown(). 2936 */ 2937 if (so->so_type != SOCK_DGRAM && !SOLISTENING(so)) { 2938 SOCK_UNLOCK(so); 2939 return (ENOTCONN); 2940 } 2941 soerror_enotconn = 1; 2942 } 2943 2944 if (SOLISTENING(so)) { 2945 if (how != SHUT_WR) { 2946 so->so_error = ECONNABORTED; 2947 solisten_wakeup(so); /* unlocks so */ 2948 } else { 2949 SOCK_UNLOCK(so); 2950 } 2951 goto done; 2952 } 2953 SOCK_UNLOCK(so); 2954 2955 CURVNET_SET(so->so_vnet); 2956 pr = so->so_proto; 2957 if (pr->pr_flush != NULL) 2958 pr->pr_flush(so, how); 2959 if (how != SHUT_WR) 2960 sorflush(so); 2961 if (how != SHUT_RD) { 2962 error = pr->pr_shutdown(so); 2963 wakeup(&so->so_timeo); 2964 CURVNET_RESTORE(); 2965 return ((error == 0 && soerror_enotconn) ? ENOTCONN : error); 2966 } 2967 wakeup(&so->so_timeo); 2968 CURVNET_RESTORE(); 2969 2970 done: 2971 return (soerror_enotconn ? ENOTCONN : 0); 2972 } 2973 2974 void 2975 sorflush(struct socket *so) 2976 { 2977 struct protosw *pr; 2978 int error; 2979 2980 VNET_SO_ASSERT(so); 2981 2982 /* 2983 * Dislodge threads currently blocked in receive and wait to acquire 2984 * a lock against other simultaneous readers before clearing the 2985 * socket buffer. Don't let our acquire be interrupted by a signal 2986 * despite any existing socket disposition on interruptable waiting. 2987 */ 2988 socantrcvmore(so); 2989 2990 error = SOCK_IO_RECV_LOCK(so, SBL_WAIT | SBL_NOINTR); 2991 if (error != 0) { 2992 KASSERT(SOLISTENING(so), 2993 ("%s: soiolock(%p) failed", __func__, so)); 2994 return; 2995 } 2996 2997 pr = so->so_proto; 2998 if (pr->pr_flags & PR_RIGHTS) { 2999 MPASS(pr->pr_domain->dom_dispose != NULL); 3000 (*pr->pr_domain->dom_dispose)(so); 3001 } else { 3002 sbrelease(so, SO_RCV); 3003 SOCK_IO_RECV_UNLOCK(so); 3004 } 3005 3006 } 3007 3008 /* 3009 * Wrapper for Socket established helper hook. 3010 * Parameters: socket, context of the hook point, hook id. 3011 */ 3012 static int inline 3013 hhook_run_socket(struct socket *so, void *hctx, int32_t h_id) 3014 { 3015 struct socket_hhook_data hhook_data = { 3016 .so = so, 3017 .hctx = hctx, 3018 .m = NULL, 3019 .status = 0 3020 }; 3021 3022 CURVNET_SET(so->so_vnet); 3023 HHOOKS_RUN_IF(V_socket_hhh[h_id], &hhook_data, &so->osd); 3024 CURVNET_RESTORE(); 3025 3026 /* Ugly but needed, since hhooks return void for now */ 3027 return (hhook_data.status); 3028 } 3029 3030 /* 3031 * Perhaps this routine, and sooptcopyout(), below, ought to come in an 3032 * additional variant to handle the case where the option value needs to be 3033 * some kind of integer, but not a specific size. In addition to their use 3034 * here, these functions are also called by the protocol-level pr_ctloutput() 3035 * routines. 3036 */ 3037 int 3038 sooptcopyin(struct sockopt *sopt, void *buf, size_t len, size_t minlen) 3039 { 3040 size_t valsize; 3041 3042 /* 3043 * If the user gives us more than we wanted, we ignore it, but if we 3044 * don't get the minimum length the caller wants, we return EINVAL. 3045 * On success, sopt->sopt_valsize is set to however much we actually 3046 * retrieved. 3047 */ 3048 if ((valsize = sopt->sopt_valsize) < minlen) 3049 return EINVAL; 3050 if (valsize > len) 3051 sopt->sopt_valsize = valsize = len; 3052 3053 if (sopt->sopt_td != NULL) 3054 return (copyin(sopt->sopt_val, buf, valsize)); 3055 3056 bcopy(sopt->sopt_val, buf, valsize); 3057 return (0); 3058 } 3059 3060 /* 3061 * Kernel version of setsockopt(2). 3062 * 3063 * XXX: optlen is size_t, not socklen_t 3064 */ 3065 int 3066 so_setsockopt(struct socket *so, int level, int optname, void *optval, 3067 size_t optlen) 3068 { 3069 struct sockopt sopt; 3070 3071 sopt.sopt_level = level; 3072 sopt.sopt_name = optname; 3073 sopt.sopt_dir = SOPT_SET; 3074 sopt.sopt_val = optval; 3075 sopt.sopt_valsize = optlen; 3076 sopt.sopt_td = NULL; 3077 return (sosetopt(so, &sopt)); 3078 } 3079 3080 int 3081 sosetopt(struct socket *so, struct sockopt *sopt) 3082 { 3083 int error, optval; 3084 struct linger l; 3085 struct timeval tv; 3086 sbintime_t val, *valp; 3087 uint32_t val32; 3088 #ifdef MAC 3089 struct mac extmac; 3090 #endif 3091 3092 CURVNET_SET(so->so_vnet); 3093 error = 0; 3094 if (sopt->sopt_level != SOL_SOCKET) { 3095 if (so->so_proto->pr_ctloutput != NULL) 3096 error = (*so->so_proto->pr_ctloutput)(so, sopt); 3097 else 3098 error = ENOPROTOOPT; 3099 } else { 3100 switch (sopt->sopt_name) { 3101 case SO_ACCEPTFILTER: 3102 error = accept_filt_setopt(so, sopt); 3103 if (error) 3104 goto bad; 3105 break; 3106 3107 case SO_LINGER: 3108 error = sooptcopyin(sopt, &l, sizeof l, sizeof l); 3109 if (error) 3110 goto bad; 3111 if (l.l_linger < 0 || 3112 l.l_linger > USHRT_MAX || 3113 l.l_linger > (INT_MAX / hz)) { 3114 error = EDOM; 3115 goto bad; 3116 } 3117 SOCK_LOCK(so); 3118 so->so_linger = l.l_linger; 3119 if (l.l_onoff) 3120 so->so_options |= SO_LINGER; 3121 else 3122 so->so_options &= ~SO_LINGER; 3123 SOCK_UNLOCK(so); 3124 break; 3125 3126 case SO_DEBUG: 3127 case SO_KEEPALIVE: 3128 case SO_DONTROUTE: 3129 case SO_USELOOPBACK: 3130 case SO_BROADCAST: 3131 case SO_REUSEADDR: 3132 case SO_REUSEPORT: 3133 case SO_REUSEPORT_LB: 3134 case SO_OOBINLINE: 3135 case SO_TIMESTAMP: 3136 case SO_BINTIME: 3137 case SO_NOSIGPIPE: 3138 case SO_NO_DDP: 3139 case SO_NO_OFFLOAD: 3140 case SO_RERROR: 3141 error = sooptcopyin(sopt, &optval, sizeof optval, 3142 sizeof optval); 3143 if (error) 3144 goto bad; 3145 SOCK_LOCK(so); 3146 if (optval) 3147 so->so_options |= sopt->sopt_name; 3148 else 3149 so->so_options &= ~sopt->sopt_name; 3150 SOCK_UNLOCK(so); 3151 break; 3152 3153 case SO_SETFIB: 3154 error = sooptcopyin(sopt, &optval, sizeof optval, 3155 sizeof optval); 3156 if (error) 3157 goto bad; 3158 3159 if (optval < 0 || optval >= rt_numfibs) { 3160 error = EINVAL; 3161 goto bad; 3162 } 3163 if (((so->so_proto->pr_domain->dom_family == PF_INET) || 3164 (so->so_proto->pr_domain->dom_family == PF_INET6) || 3165 (so->so_proto->pr_domain->dom_family == PF_ROUTE))) 3166 so->so_fibnum = optval; 3167 else 3168 so->so_fibnum = 0; 3169 break; 3170 3171 case SO_USER_COOKIE: 3172 error = sooptcopyin(sopt, &val32, sizeof val32, 3173 sizeof val32); 3174 if (error) 3175 goto bad; 3176 so->so_user_cookie = val32; 3177 break; 3178 3179 case SO_SNDBUF: 3180 case SO_RCVBUF: 3181 case SO_SNDLOWAT: 3182 case SO_RCVLOWAT: 3183 error = so->so_proto->pr_setsbopt(so, sopt); 3184 if (error) 3185 goto bad; 3186 break; 3187 3188 case SO_SNDTIMEO: 3189 case SO_RCVTIMEO: 3190 #ifdef COMPAT_FREEBSD32 3191 if (SV_CURPROC_FLAG(SV_ILP32)) { 3192 struct timeval32 tv32; 3193 3194 error = sooptcopyin(sopt, &tv32, sizeof tv32, 3195 sizeof tv32); 3196 CP(tv32, tv, tv_sec); 3197 CP(tv32, tv, tv_usec); 3198 } else 3199 #endif 3200 error = sooptcopyin(sopt, &tv, sizeof tv, 3201 sizeof tv); 3202 if (error) 3203 goto bad; 3204 if (tv.tv_sec < 0 || tv.tv_usec < 0 || 3205 tv.tv_usec >= 1000000) { 3206 error = EDOM; 3207 goto bad; 3208 } 3209 if (tv.tv_sec > INT32_MAX) 3210 val = SBT_MAX; 3211 else 3212 val = tvtosbt(tv); 3213 SOCK_LOCK(so); 3214 valp = sopt->sopt_name == SO_SNDTIMEO ? 3215 (SOLISTENING(so) ? &so->sol_sbsnd_timeo : 3216 &so->so_snd.sb_timeo) : 3217 (SOLISTENING(so) ? &so->sol_sbrcv_timeo : 3218 &so->so_rcv.sb_timeo); 3219 *valp = val; 3220 SOCK_UNLOCK(so); 3221 break; 3222 3223 case SO_LABEL: 3224 #ifdef MAC 3225 error = sooptcopyin(sopt, &extmac, sizeof extmac, 3226 sizeof extmac); 3227 if (error) 3228 goto bad; 3229 error = mac_setsockopt_label(sopt->sopt_td->td_ucred, 3230 so, &extmac); 3231 #else 3232 error = EOPNOTSUPP; 3233 #endif 3234 break; 3235 3236 case SO_TS_CLOCK: 3237 error = sooptcopyin(sopt, &optval, sizeof optval, 3238 sizeof optval); 3239 if (error) 3240 goto bad; 3241 if (optval < 0 || optval > SO_TS_CLOCK_MAX) { 3242 error = EINVAL; 3243 goto bad; 3244 } 3245 so->so_ts_clock = optval; 3246 break; 3247 3248 case SO_MAX_PACING_RATE: 3249 error = sooptcopyin(sopt, &val32, sizeof(val32), 3250 sizeof(val32)); 3251 if (error) 3252 goto bad; 3253 so->so_max_pacing_rate = val32; 3254 break; 3255 3256 default: 3257 if (V_socket_hhh[HHOOK_SOCKET_OPT]->hhh_nhooks > 0) 3258 error = hhook_run_socket(so, sopt, 3259 HHOOK_SOCKET_OPT); 3260 else 3261 error = ENOPROTOOPT; 3262 break; 3263 } 3264 if (error == 0 && so->so_proto->pr_ctloutput != NULL) 3265 (void)(*so->so_proto->pr_ctloutput)(so, sopt); 3266 } 3267 bad: 3268 CURVNET_RESTORE(); 3269 return (error); 3270 } 3271 3272 /* 3273 * Helper routine for getsockopt. 3274 */ 3275 int 3276 sooptcopyout(struct sockopt *sopt, const void *buf, size_t len) 3277 { 3278 int error; 3279 size_t valsize; 3280 3281 error = 0; 3282 3283 /* 3284 * Documented get behavior is that we always return a value, possibly 3285 * truncated to fit in the user's buffer. Traditional behavior is 3286 * that we always tell the user precisely how much we copied, rather 3287 * than something useful like the total amount we had available for 3288 * her. Note that this interface is not idempotent; the entire 3289 * answer must be generated ahead of time. 3290 */ 3291 valsize = min(len, sopt->sopt_valsize); 3292 sopt->sopt_valsize = valsize; 3293 if (sopt->sopt_val != NULL) { 3294 if (sopt->sopt_td != NULL) 3295 error = copyout(buf, sopt->sopt_val, valsize); 3296 else 3297 bcopy(buf, sopt->sopt_val, valsize); 3298 } 3299 return (error); 3300 } 3301 3302 int 3303 sogetopt(struct socket *so, struct sockopt *sopt) 3304 { 3305 int error, optval; 3306 struct linger l; 3307 struct timeval tv; 3308 #ifdef MAC 3309 struct mac extmac; 3310 #endif 3311 3312 CURVNET_SET(so->so_vnet); 3313 error = 0; 3314 if (sopt->sopt_level != SOL_SOCKET) { 3315 if (so->so_proto->pr_ctloutput != NULL) 3316 error = (*so->so_proto->pr_ctloutput)(so, sopt); 3317 else 3318 error = ENOPROTOOPT; 3319 CURVNET_RESTORE(); 3320 return (error); 3321 } else { 3322 switch (sopt->sopt_name) { 3323 case SO_ACCEPTFILTER: 3324 error = accept_filt_getopt(so, sopt); 3325 break; 3326 3327 case SO_LINGER: 3328 SOCK_LOCK(so); 3329 l.l_onoff = so->so_options & SO_LINGER; 3330 l.l_linger = so->so_linger; 3331 SOCK_UNLOCK(so); 3332 error = sooptcopyout(sopt, &l, sizeof l); 3333 break; 3334 3335 case SO_USELOOPBACK: 3336 case SO_DONTROUTE: 3337 case SO_DEBUG: 3338 case SO_KEEPALIVE: 3339 case SO_REUSEADDR: 3340 case SO_REUSEPORT: 3341 case SO_REUSEPORT_LB: 3342 case SO_BROADCAST: 3343 case SO_OOBINLINE: 3344 case SO_ACCEPTCONN: 3345 case SO_TIMESTAMP: 3346 case SO_BINTIME: 3347 case SO_NOSIGPIPE: 3348 case SO_NO_DDP: 3349 case SO_NO_OFFLOAD: 3350 case SO_RERROR: 3351 optval = so->so_options & sopt->sopt_name; 3352 integer: 3353 error = sooptcopyout(sopt, &optval, sizeof optval); 3354 break; 3355 3356 case SO_DOMAIN: 3357 optval = so->so_proto->pr_domain->dom_family; 3358 goto integer; 3359 3360 case SO_TYPE: 3361 optval = so->so_type; 3362 goto integer; 3363 3364 case SO_PROTOCOL: 3365 optval = so->so_proto->pr_protocol; 3366 goto integer; 3367 3368 case SO_ERROR: 3369 SOCK_LOCK(so); 3370 if (so->so_error) { 3371 optval = so->so_error; 3372 so->so_error = 0; 3373 } else { 3374 optval = so->so_rerror; 3375 so->so_rerror = 0; 3376 } 3377 SOCK_UNLOCK(so); 3378 goto integer; 3379 3380 case SO_SNDBUF: 3381 optval = SOLISTENING(so) ? so->sol_sbsnd_hiwat : 3382 so->so_snd.sb_hiwat; 3383 goto integer; 3384 3385 case SO_RCVBUF: 3386 optval = SOLISTENING(so) ? so->sol_sbrcv_hiwat : 3387 so->so_rcv.sb_hiwat; 3388 goto integer; 3389 3390 case SO_SNDLOWAT: 3391 optval = SOLISTENING(so) ? so->sol_sbsnd_lowat : 3392 so->so_snd.sb_lowat; 3393 goto integer; 3394 3395 case SO_RCVLOWAT: 3396 optval = SOLISTENING(so) ? so->sol_sbrcv_lowat : 3397 so->so_rcv.sb_lowat; 3398 goto integer; 3399 3400 case SO_SNDTIMEO: 3401 case SO_RCVTIMEO: 3402 SOCK_LOCK(so); 3403 tv = sbttotv(sopt->sopt_name == SO_SNDTIMEO ? 3404 (SOLISTENING(so) ? so->sol_sbsnd_timeo : 3405 so->so_snd.sb_timeo) : 3406 (SOLISTENING(so) ? so->sol_sbrcv_timeo : 3407 so->so_rcv.sb_timeo)); 3408 SOCK_UNLOCK(so); 3409 #ifdef COMPAT_FREEBSD32 3410 if (SV_CURPROC_FLAG(SV_ILP32)) { 3411 struct timeval32 tv32; 3412 3413 CP(tv, tv32, tv_sec); 3414 CP(tv, tv32, tv_usec); 3415 error = sooptcopyout(sopt, &tv32, sizeof tv32); 3416 } else 3417 #endif 3418 error = sooptcopyout(sopt, &tv, sizeof tv); 3419 break; 3420 3421 case SO_LABEL: 3422 #ifdef MAC 3423 error = sooptcopyin(sopt, &extmac, sizeof(extmac), 3424 sizeof(extmac)); 3425 if (error) 3426 goto bad; 3427 error = mac_getsockopt_label(sopt->sopt_td->td_ucred, 3428 so, &extmac); 3429 if (error) 3430 goto bad; 3431 error = sooptcopyout(sopt, &extmac, sizeof extmac); 3432 #else 3433 error = EOPNOTSUPP; 3434 #endif 3435 break; 3436 3437 case SO_PEERLABEL: 3438 #ifdef MAC 3439 error = sooptcopyin(sopt, &extmac, sizeof(extmac), 3440 sizeof(extmac)); 3441 if (error) 3442 goto bad; 3443 error = mac_getsockopt_peerlabel( 3444 sopt->sopt_td->td_ucred, so, &extmac); 3445 if (error) 3446 goto bad; 3447 error = sooptcopyout(sopt, &extmac, sizeof extmac); 3448 #else 3449 error = EOPNOTSUPP; 3450 #endif 3451 break; 3452 3453 case SO_LISTENQLIMIT: 3454 optval = SOLISTENING(so) ? so->sol_qlimit : 0; 3455 goto integer; 3456 3457 case SO_LISTENQLEN: 3458 optval = SOLISTENING(so) ? so->sol_qlen : 0; 3459 goto integer; 3460 3461 case SO_LISTENINCQLEN: 3462 optval = SOLISTENING(so) ? so->sol_incqlen : 0; 3463 goto integer; 3464 3465 case SO_TS_CLOCK: 3466 optval = so->so_ts_clock; 3467 goto integer; 3468 3469 case SO_MAX_PACING_RATE: 3470 optval = so->so_max_pacing_rate; 3471 goto integer; 3472 3473 default: 3474 if (V_socket_hhh[HHOOK_SOCKET_OPT]->hhh_nhooks > 0) 3475 error = hhook_run_socket(so, sopt, 3476 HHOOK_SOCKET_OPT); 3477 else 3478 error = ENOPROTOOPT; 3479 break; 3480 } 3481 } 3482 #ifdef MAC 3483 bad: 3484 #endif 3485 CURVNET_RESTORE(); 3486 return (error); 3487 } 3488 3489 int 3490 soopt_getm(struct sockopt *sopt, struct mbuf **mp) 3491 { 3492 struct mbuf *m, *m_prev; 3493 int sopt_size = sopt->sopt_valsize; 3494 3495 MGET(m, sopt->sopt_td ? M_WAITOK : M_NOWAIT, MT_DATA); 3496 if (m == NULL) 3497 return ENOBUFS; 3498 if (sopt_size > MLEN) { 3499 MCLGET(m, sopt->sopt_td ? M_WAITOK : M_NOWAIT); 3500 if ((m->m_flags & M_EXT) == 0) { 3501 m_free(m); 3502 return ENOBUFS; 3503 } 3504 m->m_len = min(MCLBYTES, sopt_size); 3505 } else { 3506 m->m_len = min(MLEN, sopt_size); 3507 } 3508 sopt_size -= m->m_len; 3509 *mp = m; 3510 m_prev = m; 3511 3512 while (sopt_size) { 3513 MGET(m, sopt->sopt_td ? M_WAITOK : M_NOWAIT, MT_DATA); 3514 if (m == NULL) { 3515 m_freem(*mp); 3516 return ENOBUFS; 3517 } 3518 if (sopt_size > MLEN) { 3519 MCLGET(m, sopt->sopt_td != NULL ? M_WAITOK : 3520 M_NOWAIT); 3521 if ((m->m_flags & M_EXT) == 0) { 3522 m_freem(m); 3523 m_freem(*mp); 3524 return ENOBUFS; 3525 } 3526 m->m_len = min(MCLBYTES, sopt_size); 3527 } else { 3528 m->m_len = min(MLEN, sopt_size); 3529 } 3530 sopt_size -= m->m_len; 3531 m_prev->m_next = m; 3532 m_prev = m; 3533 } 3534 return (0); 3535 } 3536 3537 int 3538 soopt_mcopyin(struct sockopt *sopt, struct mbuf *m) 3539 { 3540 struct mbuf *m0 = m; 3541 3542 if (sopt->sopt_val == NULL) 3543 return (0); 3544 while (m != NULL && sopt->sopt_valsize >= m->m_len) { 3545 if (sopt->sopt_td != NULL) { 3546 int error; 3547 3548 error = copyin(sopt->sopt_val, mtod(m, char *), 3549 m->m_len); 3550 if (error != 0) { 3551 m_freem(m0); 3552 return(error); 3553 } 3554 } else 3555 bcopy(sopt->sopt_val, mtod(m, char *), m->m_len); 3556 sopt->sopt_valsize -= m->m_len; 3557 sopt->sopt_val = (char *)sopt->sopt_val + m->m_len; 3558 m = m->m_next; 3559 } 3560 if (m != NULL) /* should be allocated enoughly at ip6_sooptmcopyin() */ 3561 panic("ip6_sooptmcopyin"); 3562 return (0); 3563 } 3564 3565 int 3566 soopt_mcopyout(struct sockopt *sopt, struct mbuf *m) 3567 { 3568 struct mbuf *m0 = m; 3569 size_t valsize = 0; 3570 3571 if (sopt->sopt_val == NULL) 3572 return (0); 3573 while (m != NULL && sopt->sopt_valsize >= m->m_len) { 3574 if (sopt->sopt_td != NULL) { 3575 int error; 3576 3577 error = copyout(mtod(m, char *), sopt->sopt_val, 3578 m->m_len); 3579 if (error != 0) { 3580 m_freem(m0); 3581 return(error); 3582 } 3583 } else 3584 bcopy(mtod(m, char *), sopt->sopt_val, m->m_len); 3585 sopt->sopt_valsize -= m->m_len; 3586 sopt->sopt_val = (char *)sopt->sopt_val + m->m_len; 3587 valsize += m->m_len; 3588 m = m->m_next; 3589 } 3590 if (m != NULL) { 3591 /* enough soopt buffer should be given from user-land */ 3592 m_freem(m0); 3593 return(EINVAL); 3594 } 3595 sopt->sopt_valsize = valsize; 3596 return (0); 3597 } 3598 3599 /* 3600 * sohasoutofband(): protocol notifies socket layer of the arrival of new 3601 * out-of-band data, which will then notify socket consumers. 3602 */ 3603 void 3604 sohasoutofband(struct socket *so) 3605 { 3606 3607 if (so->so_sigio != NULL) 3608 pgsigio(&so->so_sigio, SIGURG, 0); 3609 selwakeuppri(&so->so_rdsel, PSOCK); 3610 } 3611 3612 int 3613 sopoll(struct socket *so, int events, struct ucred *active_cred, 3614 struct thread *td) 3615 { 3616 3617 /* 3618 * We do not need to set or assert curvnet as long as everyone uses 3619 * sopoll_generic(). 3620 */ 3621 return (so->so_proto->pr_sopoll(so, events, active_cred, td)); 3622 } 3623 3624 int 3625 sopoll_generic(struct socket *so, int events, struct ucred *active_cred, 3626 struct thread *td) 3627 { 3628 int revents; 3629 3630 SOCK_LOCK(so); 3631 if (SOLISTENING(so)) { 3632 if (!(events & (POLLIN | POLLRDNORM))) 3633 revents = 0; 3634 else if (!TAILQ_EMPTY(&so->sol_comp)) 3635 revents = events & (POLLIN | POLLRDNORM); 3636 else if ((events & POLLINIGNEOF) == 0 && so->so_error) 3637 revents = (events & (POLLIN | POLLRDNORM)) | POLLHUP; 3638 else { 3639 selrecord(td, &so->so_rdsel); 3640 revents = 0; 3641 } 3642 } else { 3643 revents = 0; 3644 SOCK_SENDBUF_LOCK(so); 3645 SOCK_RECVBUF_LOCK(so); 3646 if (events & (POLLIN | POLLRDNORM)) 3647 if (soreadabledata(so)) 3648 revents |= events & (POLLIN | POLLRDNORM); 3649 if (events & (POLLOUT | POLLWRNORM)) 3650 if (sowriteable(so)) 3651 revents |= events & (POLLOUT | POLLWRNORM); 3652 if (events & (POLLPRI | POLLRDBAND)) 3653 if (so->so_oobmark || 3654 (so->so_rcv.sb_state & SBS_RCVATMARK)) 3655 revents |= events & (POLLPRI | POLLRDBAND); 3656 if ((events & POLLINIGNEOF) == 0) { 3657 if (so->so_rcv.sb_state & SBS_CANTRCVMORE) { 3658 revents |= events & (POLLIN | POLLRDNORM); 3659 if (so->so_snd.sb_state & SBS_CANTSENDMORE) 3660 revents |= POLLHUP; 3661 } 3662 } 3663 if (so->so_rcv.sb_state & SBS_CANTRCVMORE) 3664 revents |= events & POLLRDHUP; 3665 if (revents == 0) { 3666 if (events & 3667 (POLLIN | POLLPRI | POLLRDNORM | POLLRDBAND | POLLRDHUP)) { 3668 selrecord(td, &so->so_rdsel); 3669 so->so_rcv.sb_flags |= SB_SEL; 3670 } 3671 if (events & (POLLOUT | POLLWRNORM)) { 3672 selrecord(td, &so->so_wrsel); 3673 so->so_snd.sb_flags |= SB_SEL; 3674 } 3675 } 3676 SOCK_RECVBUF_UNLOCK(so); 3677 SOCK_SENDBUF_UNLOCK(so); 3678 } 3679 SOCK_UNLOCK(so); 3680 return (revents); 3681 } 3682 3683 int 3684 soo_kqfilter(struct file *fp, struct knote *kn) 3685 { 3686 struct socket *so = kn->kn_fp->f_data; 3687 struct sockbuf *sb; 3688 sb_which which; 3689 struct knlist *knl; 3690 3691 switch (kn->kn_filter) { 3692 case EVFILT_READ: 3693 kn->kn_fop = &soread_filtops; 3694 knl = &so->so_rdsel.si_note; 3695 sb = &so->so_rcv; 3696 which = SO_RCV; 3697 break; 3698 case EVFILT_WRITE: 3699 kn->kn_fop = &sowrite_filtops; 3700 knl = &so->so_wrsel.si_note; 3701 sb = &so->so_snd; 3702 which = SO_SND; 3703 break; 3704 case EVFILT_EMPTY: 3705 kn->kn_fop = &soempty_filtops; 3706 knl = &so->so_wrsel.si_note; 3707 sb = &so->so_snd; 3708 which = SO_SND; 3709 break; 3710 default: 3711 return (EINVAL); 3712 } 3713 3714 SOCK_LOCK(so); 3715 if (SOLISTENING(so)) { 3716 knlist_add(knl, kn, 1); 3717 } else { 3718 SOCK_BUF_LOCK(so, which); 3719 knlist_add(knl, kn, 1); 3720 sb->sb_flags |= SB_KNOTE; 3721 SOCK_BUF_UNLOCK(so, which); 3722 } 3723 SOCK_UNLOCK(so); 3724 return (0); 3725 } 3726 3727 static void 3728 filt_sordetach(struct knote *kn) 3729 { 3730 struct socket *so = kn->kn_fp->f_data; 3731 3732 so_rdknl_lock(so); 3733 knlist_remove(&so->so_rdsel.si_note, kn, 1); 3734 if (!SOLISTENING(so) && knlist_empty(&so->so_rdsel.si_note)) 3735 so->so_rcv.sb_flags &= ~SB_KNOTE; 3736 so_rdknl_unlock(so); 3737 } 3738 3739 /*ARGSUSED*/ 3740 static int 3741 filt_soread(struct knote *kn, long hint) 3742 { 3743 struct socket *so; 3744 3745 so = kn->kn_fp->f_data; 3746 3747 if (SOLISTENING(so)) { 3748 SOCK_LOCK_ASSERT(so); 3749 kn->kn_data = so->sol_qlen; 3750 if (so->so_error) { 3751 kn->kn_flags |= EV_EOF; 3752 kn->kn_fflags = so->so_error; 3753 return (1); 3754 } 3755 return (!TAILQ_EMPTY(&so->sol_comp)); 3756 } 3757 3758 SOCK_RECVBUF_LOCK_ASSERT(so); 3759 3760 kn->kn_data = sbavail(&so->so_rcv) - so->so_rcv.sb_ctl; 3761 if (so->so_rcv.sb_state & SBS_CANTRCVMORE) { 3762 kn->kn_flags |= EV_EOF; 3763 kn->kn_fflags = so->so_error; 3764 return (1); 3765 } else if (so->so_error || so->so_rerror) 3766 return (1); 3767 3768 if (kn->kn_sfflags & NOTE_LOWAT) { 3769 if (kn->kn_data >= kn->kn_sdata) 3770 return (1); 3771 } else if (sbavail(&so->so_rcv) >= so->so_rcv.sb_lowat) 3772 return (1); 3773 3774 /* This hook returning non-zero indicates an event, not error */ 3775 return (hhook_run_socket(so, NULL, HHOOK_FILT_SOREAD)); 3776 } 3777 3778 static void 3779 filt_sowdetach(struct knote *kn) 3780 { 3781 struct socket *so = kn->kn_fp->f_data; 3782 3783 so_wrknl_lock(so); 3784 knlist_remove(&so->so_wrsel.si_note, kn, 1); 3785 if (!SOLISTENING(so) && knlist_empty(&so->so_wrsel.si_note)) 3786 so->so_snd.sb_flags &= ~SB_KNOTE; 3787 so_wrknl_unlock(so); 3788 } 3789 3790 /*ARGSUSED*/ 3791 static int 3792 filt_sowrite(struct knote *kn, long hint) 3793 { 3794 struct socket *so; 3795 3796 so = kn->kn_fp->f_data; 3797 3798 if (SOLISTENING(so)) 3799 return (0); 3800 3801 SOCK_SENDBUF_LOCK_ASSERT(so); 3802 kn->kn_data = sbspace(&so->so_snd); 3803 3804 hhook_run_socket(so, kn, HHOOK_FILT_SOWRITE); 3805 3806 if (so->so_snd.sb_state & SBS_CANTSENDMORE) { 3807 kn->kn_flags |= EV_EOF; 3808 kn->kn_fflags = so->so_error; 3809 return (1); 3810 } else if (so->so_error) /* temporary udp error */ 3811 return (1); 3812 else if (((so->so_state & SS_ISCONNECTED) == 0) && 3813 (so->so_proto->pr_flags & PR_CONNREQUIRED)) 3814 return (0); 3815 else if (kn->kn_sfflags & NOTE_LOWAT) 3816 return (kn->kn_data >= kn->kn_sdata); 3817 else 3818 return (kn->kn_data >= so->so_snd.sb_lowat); 3819 } 3820 3821 static int 3822 filt_soempty(struct knote *kn, long hint) 3823 { 3824 struct socket *so; 3825 3826 so = kn->kn_fp->f_data; 3827 3828 if (SOLISTENING(so)) 3829 return (1); 3830 3831 SOCK_SENDBUF_LOCK_ASSERT(so); 3832 kn->kn_data = sbused(&so->so_snd); 3833 3834 if (kn->kn_data == 0) 3835 return (1); 3836 else 3837 return (0); 3838 } 3839 3840 int 3841 socheckuid(struct socket *so, uid_t uid) 3842 { 3843 3844 if (so == NULL) 3845 return (EPERM); 3846 if (so->so_cred->cr_uid != uid) 3847 return (EPERM); 3848 return (0); 3849 } 3850 3851 /* 3852 * These functions are used by protocols to notify the socket layer (and its 3853 * consumers) of state changes in the sockets driven by protocol-side events. 3854 */ 3855 3856 /* 3857 * Procedures to manipulate state flags of socket and do appropriate wakeups. 3858 * 3859 * Normal sequence from the active (originating) side is that 3860 * soisconnecting() is called during processing of connect() call, resulting 3861 * in an eventual call to soisconnected() if/when the connection is 3862 * established. When the connection is torn down soisdisconnecting() is 3863 * called during processing of disconnect() call, and soisdisconnected() is 3864 * called when the connection to the peer is totally severed. The semantics 3865 * of these routines are such that connectionless protocols can call 3866 * soisconnected() and soisdisconnected() only, bypassing the in-progress 3867 * calls when setting up a ``connection'' takes no time. 3868 * 3869 * From the passive side, a socket is created with two queues of sockets: 3870 * so_incomp for connections in progress and so_comp for connections already 3871 * made and awaiting user acceptance. As a protocol is preparing incoming 3872 * connections, it creates a socket structure queued on so_incomp by calling 3873 * sonewconn(). When the connection is established, soisconnected() is 3874 * called, and transfers the socket structure to so_comp, making it available 3875 * to accept(). 3876 * 3877 * If a socket is closed with sockets on either so_incomp or so_comp, these 3878 * sockets are dropped. 3879 * 3880 * If higher-level protocols are implemented in the kernel, the wakeups done 3881 * here will sometimes cause software-interrupt process scheduling. 3882 */ 3883 void 3884 soisconnecting(struct socket *so) 3885 { 3886 3887 SOCK_LOCK(so); 3888 so->so_state &= ~(SS_ISCONNECTED|SS_ISDISCONNECTING); 3889 so->so_state |= SS_ISCONNECTING; 3890 SOCK_UNLOCK(so); 3891 } 3892 3893 void 3894 soisconnected(struct socket *so) 3895 { 3896 bool last __diagused; 3897 3898 SOCK_LOCK(so); 3899 so->so_state &= ~(SS_ISCONNECTING|SS_ISDISCONNECTING|SS_ISCONFIRMING); 3900 so->so_state |= SS_ISCONNECTED; 3901 3902 if (so->so_qstate == SQ_INCOMP) { 3903 struct socket *head = so->so_listen; 3904 int ret; 3905 3906 KASSERT(head, ("%s: so %p on incomp of NULL", __func__, so)); 3907 /* 3908 * Promoting a socket from incomplete queue to complete, we 3909 * need to go through reverse order of locking. We first do 3910 * trylock, and if that doesn't succeed, we go the hard way 3911 * leaving a reference and rechecking consistency after proper 3912 * locking. 3913 */ 3914 if (__predict_false(SOLISTEN_TRYLOCK(head) == 0)) { 3915 soref(head); 3916 SOCK_UNLOCK(so); 3917 SOLISTEN_LOCK(head); 3918 SOCK_LOCK(so); 3919 if (__predict_false(head != so->so_listen)) { 3920 /* 3921 * The socket went off the listen queue, 3922 * should be lost race to close(2) of sol. 3923 * The socket is about to soabort(). 3924 */ 3925 SOCK_UNLOCK(so); 3926 sorele_locked(head); 3927 return; 3928 } 3929 last = refcount_release(&head->so_count); 3930 KASSERT(!last, ("%s: released last reference for %p", 3931 __func__, head)); 3932 } 3933 again: 3934 if ((so->so_options & SO_ACCEPTFILTER) == 0) { 3935 TAILQ_REMOVE(&head->sol_incomp, so, so_list); 3936 head->sol_incqlen--; 3937 TAILQ_INSERT_TAIL(&head->sol_comp, so, so_list); 3938 head->sol_qlen++; 3939 so->so_qstate = SQ_COMP; 3940 SOCK_UNLOCK(so); 3941 solisten_wakeup(head); /* unlocks */ 3942 } else { 3943 SOCK_RECVBUF_LOCK(so); 3944 soupcall_set(so, SO_RCV, 3945 head->sol_accept_filter->accf_callback, 3946 head->sol_accept_filter_arg); 3947 so->so_options &= ~SO_ACCEPTFILTER; 3948 ret = head->sol_accept_filter->accf_callback(so, 3949 head->sol_accept_filter_arg, M_NOWAIT); 3950 if (ret == SU_ISCONNECTED) { 3951 soupcall_clear(so, SO_RCV); 3952 SOCK_RECVBUF_UNLOCK(so); 3953 goto again; 3954 } 3955 SOCK_RECVBUF_UNLOCK(so); 3956 SOCK_UNLOCK(so); 3957 SOLISTEN_UNLOCK(head); 3958 } 3959 return; 3960 } 3961 SOCK_UNLOCK(so); 3962 wakeup(&so->so_timeo); 3963 sorwakeup(so); 3964 sowwakeup(so); 3965 } 3966 3967 void 3968 soisdisconnecting(struct socket *so) 3969 { 3970 3971 SOCK_LOCK(so); 3972 so->so_state &= ~SS_ISCONNECTING; 3973 so->so_state |= SS_ISDISCONNECTING; 3974 3975 if (!SOLISTENING(so)) { 3976 SOCK_RECVBUF_LOCK(so); 3977 socantrcvmore_locked(so); 3978 SOCK_SENDBUF_LOCK(so); 3979 socantsendmore_locked(so); 3980 } 3981 SOCK_UNLOCK(so); 3982 wakeup(&so->so_timeo); 3983 } 3984 3985 void 3986 soisdisconnected(struct socket *so) 3987 { 3988 3989 SOCK_LOCK(so); 3990 3991 /* 3992 * There is at least one reader of so_state that does not 3993 * acquire socket lock, namely soreceive_generic(). Ensure 3994 * that it never sees all flags that track connection status 3995 * cleared, by ordering the update with a barrier semantic of 3996 * our release thread fence. 3997 */ 3998 so->so_state |= SS_ISDISCONNECTED; 3999 atomic_thread_fence_rel(); 4000 so->so_state &= ~(SS_ISCONNECTING|SS_ISCONNECTED|SS_ISDISCONNECTING); 4001 4002 if (!SOLISTENING(so)) { 4003 SOCK_UNLOCK(so); 4004 SOCK_RECVBUF_LOCK(so); 4005 socantrcvmore_locked(so); 4006 SOCK_SENDBUF_LOCK(so); 4007 sbdrop_locked(&so->so_snd, sbused(&so->so_snd)); 4008 socantsendmore_locked(so); 4009 } else 4010 SOCK_UNLOCK(so); 4011 wakeup(&so->so_timeo); 4012 } 4013 4014 int 4015 soiolock(struct socket *so, struct sx *sx, int flags) 4016 { 4017 int error; 4018 4019 KASSERT((flags & SBL_VALID) == flags, 4020 ("soiolock: invalid flags %#x", flags)); 4021 4022 if ((flags & SBL_WAIT) != 0) { 4023 if ((flags & SBL_NOINTR) != 0) { 4024 sx_xlock(sx); 4025 } else { 4026 error = sx_xlock_sig(sx); 4027 if (error != 0) 4028 return (error); 4029 } 4030 } else if (!sx_try_xlock(sx)) { 4031 return (EWOULDBLOCK); 4032 } 4033 4034 if (__predict_false(SOLISTENING(so))) { 4035 sx_xunlock(sx); 4036 return (ENOTCONN); 4037 } 4038 return (0); 4039 } 4040 4041 void 4042 soiounlock(struct sx *sx) 4043 { 4044 sx_xunlock(sx); 4045 } 4046 4047 /* 4048 * Make a copy of a sockaddr in a malloced buffer of type M_SONAME. 4049 */ 4050 struct sockaddr * 4051 sodupsockaddr(const struct sockaddr *sa, int mflags) 4052 { 4053 struct sockaddr *sa2; 4054 4055 sa2 = malloc(sa->sa_len, M_SONAME, mflags); 4056 if (sa2) 4057 bcopy(sa, sa2, sa->sa_len); 4058 return sa2; 4059 } 4060 4061 /* 4062 * Register per-socket destructor. 4063 */ 4064 void 4065 sodtor_set(struct socket *so, so_dtor_t *func) 4066 { 4067 4068 SOCK_LOCK_ASSERT(so); 4069 so->so_dtor = func; 4070 } 4071 4072 /* 4073 * Register per-socket buffer upcalls. 4074 */ 4075 void 4076 soupcall_set(struct socket *so, sb_which which, so_upcall_t func, void *arg) 4077 { 4078 struct sockbuf *sb; 4079 4080 KASSERT(!SOLISTENING(so), ("%s: so %p listening", __func__, so)); 4081 4082 switch (which) { 4083 case SO_RCV: 4084 sb = &so->so_rcv; 4085 break; 4086 case SO_SND: 4087 sb = &so->so_snd; 4088 break; 4089 } 4090 SOCK_BUF_LOCK_ASSERT(so, which); 4091 sb->sb_upcall = func; 4092 sb->sb_upcallarg = arg; 4093 sb->sb_flags |= SB_UPCALL; 4094 } 4095 4096 void 4097 soupcall_clear(struct socket *so, sb_which which) 4098 { 4099 struct sockbuf *sb; 4100 4101 KASSERT(!SOLISTENING(so), ("%s: so %p listening", __func__, so)); 4102 4103 switch (which) { 4104 case SO_RCV: 4105 sb = &so->so_rcv; 4106 break; 4107 case SO_SND: 4108 sb = &so->so_snd; 4109 break; 4110 } 4111 SOCK_BUF_LOCK_ASSERT(so, which); 4112 KASSERT(sb->sb_upcall != NULL, 4113 ("%s: so %p no upcall to clear", __func__, so)); 4114 sb->sb_upcall = NULL; 4115 sb->sb_upcallarg = NULL; 4116 sb->sb_flags &= ~SB_UPCALL; 4117 } 4118 4119 void 4120 solisten_upcall_set(struct socket *so, so_upcall_t func, void *arg) 4121 { 4122 4123 SOLISTEN_LOCK_ASSERT(so); 4124 so->sol_upcall = func; 4125 so->sol_upcallarg = arg; 4126 } 4127 4128 static void 4129 so_rdknl_lock(void *arg) 4130 { 4131 struct socket *so = arg; 4132 4133 retry: 4134 if (SOLISTENING(so)) { 4135 SOLISTEN_LOCK(so); 4136 } else { 4137 SOCK_RECVBUF_LOCK(so); 4138 if (__predict_false(SOLISTENING(so))) { 4139 SOCK_RECVBUF_UNLOCK(so); 4140 goto retry; 4141 } 4142 } 4143 } 4144 4145 static void 4146 so_rdknl_unlock(void *arg) 4147 { 4148 struct socket *so = arg; 4149 4150 if (SOLISTENING(so)) 4151 SOLISTEN_UNLOCK(so); 4152 else 4153 SOCK_RECVBUF_UNLOCK(so); 4154 } 4155 4156 static void 4157 so_rdknl_assert_lock(void *arg, int what) 4158 { 4159 struct socket *so = arg; 4160 4161 if (what == LA_LOCKED) { 4162 if (SOLISTENING(so)) 4163 SOLISTEN_LOCK_ASSERT(so); 4164 else 4165 SOCK_RECVBUF_LOCK_ASSERT(so); 4166 } else { 4167 if (SOLISTENING(so)) 4168 SOLISTEN_UNLOCK_ASSERT(so); 4169 else 4170 SOCK_RECVBUF_UNLOCK_ASSERT(so); 4171 } 4172 } 4173 4174 static void 4175 so_wrknl_lock(void *arg) 4176 { 4177 struct socket *so = arg; 4178 4179 retry: 4180 if (SOLISTENING(so)) { 4181 SOLISTEN_LOCK(so); 4182 } else { 4183 SOCK_SENDBUF_LOCK(so); 4184 if (__predict_false(SOLISTENING(so))) { 4185 SOCK_SENDBUF_UNLOCK(so); 4186 goto retry; 4187 } 4188 } 4189 } 4190 4191 static void 4192 so_wrknl_unlock(void *arg) 4193 { 4194 struct socket *so = arg; 4195 4196 if (SOLISTENING(so)) 4197 SOLISTEN_UNLOCK(so); 4198 else 4199 SOCK_SENDBUF_UNLOCK(so); 4200 } 4201 4202 static void 4203 so_wrknl_assert_lock(void *arg, int what) 4204 { 4205 struct socket *so = arg; 4206 4207 if (what == LA_LOCKED) { 4208 if (SOLISTENING(so)) 4209 SOLISTEN_LOCK_ASSERT(so); 4210 else 4211 SOCK_SENDBUF_LOCK_ASSERT(so); 4212 } else { 4213 if (SOLISTENING(so)) 4214 SOLISTEN_UNLOCK_ASSERT(so); 4215 else 4216 SOCK_SENDBUF_UNLOCK_ASSERT(so); 4217 } 4218 } 4219 4220 /* 4221 * Create an external-format (``xsocket'') structure using the information in 4222 * the kernel-format socket structure pointed to by so. This is done to 4223 * reduce the spew of irrelevant information over this interface, to isolate 4224 * user code from changes in the kernel structure, and potentially to provide 4225 * information-hiding if we decide that some of this information should be 4226 * hidden from users. 4227 */ 4228 void 4229 sotoxsocket(struct socket *so, struct xsocket *xso) 4230 { 4231 4232 bzero(xso, sizeof(*xso)); 4233 xso->xso_len = sizeof *xso; 4234 xso->xso_so = (uintptr_t)so; 4235 xso->so_type = so->so_type; 4236 xso->so_options = so->so_options; 4237 xso->so_linger = so->so_linger; 4238 xso->so_state = so->so_state; 4239 xso->so_pcb = (uintptr_t)so->so_pcb; 4240 xso->xso_protocol = so->so_proto->pr_protocol; 4241 xso->xso_family = so->so_proto->pr_domain->dom_family; 4242 xso->so_timeo = so->so_timeo; 4243 xso->so_error = so->so_error; 4244 xso->so_uid = so->so_cred->cr_uid; 4245 xso->so_pgid = so->so_sigio ? so->so_sigio->sio_pgid : 0; 4246 if (SOLISTENING(so)) { 4247 xso->so_qlen = so->sol_qlen; 4248 xso->so_incqlen = so->sol_incqlen; 4249 xso->so_qlimit = so->sol_qlimit; 4250 xso->so_oobmark = 0; 4251 } else { 4252 xso->so_state |= so->so_qstate; 4253 xso->so_qlen = xso->so_incqlen = xso->so_qlimit = 0; 4254 xso->so_oobmark = so->so_oobmark; 4255 sbtoxsockbuf(&so->so_snd, &xso->so_snd); 4256 sbtoxsockbuf(&so->so_rcv, &xso->so_rcv); 4257 } 4258 } 4259 4260 struct sockbuf * 4261 so_sockbuf_rcv(struct socket *so) 4262 { 4263 4264 return (&so->so_rcv); 4265 } 4266 4267 struct sockbuf * 4268 so_sockbuf_snd(struct socket *so) 4269 { 4270 4271 return (&so->so_snd); 4272 } 4273 4274 int 4275 so_state_get(const struct socket *so) 4276 { 4277 4278 return (so->so_state); 4279 } 4280 4281 void 4282 so_state_set(struct socket *so, int val) 4283 { 4284 4285 so->so_state = val; 4286 } 4287 4288 int 4289 so_options_get(const struct socket *so) 4290 { 4291 4292 return (so->so_options); 4293 } 4294 4295 void 4296 so_options_set(struct socket *so, int val) 4297 { 4298 4299 so->so_options = val; 4300 } 4301 4302 int 4303 so_error_get(const struct socket *so) 4304 { 4305 4306 return (so->so_error); 4307 } 4308 4309 void 4310 so_error_set(struct socket *so, int val) 4311 { 4312 4313 so->so_error = val; 4314 } 4315 4316 int 4317 so_linger_get(const struct socket *so) 4318 { 4319 4320 return (so->so_linger); 4321 } 4322 4323 void 4324 so_linger_set(struct socket *so, int val) 4325 { 4326 4327 KASSERT(val >= 0 && val <= USHRT_MAX && val <= (INT_MAX / hz), 4328 ("%s: val %d out of range", __func__, val)); 4329 4330 so->so_linger = val; 4331 } 4332 4333 struct protosw * 4334 so_protosw_get(const struct socket *so) 4335 { 4336 4337 return (so->so_proto); 4338 } 4339 4340 void 4341 so_protosw_set(struct socket *so, struct protosw *val) 4342 { 4343 4344 so->so_proto = val; 4345 } 4346 4347 void 4348 so_sorwakeup(struct socket *so) 4349 { 4350 4351 sorwakeup(so); 4352 } 4353 4354 void 4355 so_sowwakeup(struct socket *so) 4356 { 4357 4358 sowwakeup(so); 4359 } 4360 4361 void 4362 so_sorwakeup_locked(struct socket *so) 4363 { 4364 4365 sorwakeup_locked(so); 4366 } 4367 4368 void 4369 so_sowwakeup_locked(struct socket *so) 4370 { 4371 4372 sowwakeup_locked(so); 4373 } 4374 4375 void 4376 so_lock(struct socket *so) 4377 { 4378 4379 SOCK_LOCK(so); 4380 } 4381 4382 void 4383 so_unlock(struct socket *so) 4384 { 4385 4386 SOCK_UNLOCK(so); 4387 } 4388