xref: /freebsd/sys/kern/uipc_socket.c (revision a687910fc4352117413b8e0275383e4c687d4c4c)
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 #include "opt_inet.h"
107 #include "opt_inet6.h"
108 #include "opt_kern_tls.h"
109 #include "opt_sctp.h"
110 
111 #include <sys/param.h>
112 #include <sys/systm.h>
113 #include <sys/capsicum.h>
114 #include <sys/fcntl.h>
115 #include <sys/limits.h>
116 #include <sys/lock.h>
117 #include <sys/mac.h>
118 #include <sys/malloc.h>
119 #include <sys/mbuf.h>
120 #include <sys/mutex.h>
121 #include <sys/domain.h>
122 #include <sys/file.h>			/* for struct knote */
123 #include <sys/hhook.h>
124 #include <sys/kernel.h>
125 #include <sys/khelp.h>
126 #include <sys/ktls.h>
127 #include <sys/event.h>
128 #include <sys/eventhandler.h>
129 #include <sys/poll.h>
130 #include <sys/proc.h>
131 #include <sys/protosw.h>
132 #include <sys/sbuf.h>
133 #include <sys/socket.h>
134 #include <sys/socketvar.h>
135 #include <sys/resourcevar.h>
136 #include <net/route.h>
137 #include <sys/signalvar.h>
138 #include <sys/stat.h>
139 #include <sys/sx.h>
140 #include <sys/sysctl.h>
141 #include <sys/taskqueue.h>
142 #include <sys/uio.h>
143 #include <sys/un.h>
144 #include <sys/unpcb.h>
145 #include <sys/jail.h>
146 #include <sys/syslog.h>
147 #include <netinet/in.h>
148 #include <netinet/in_pcb.h>
149 #include <netinet/tcp.h>
150 
151 #include <net/vnet.h>
152 
153 #include <security/mac/mac_framework.h>
154 
155 #include <vm/uma.h>
156 
157 #ifdef COMPAT_FREEBSD32
158 #include <sys/mount.h>
159 #include <sys/sysent.h>
160 #include <compat/freebsd32/freebsd32.h>
161 #endif
162 
163 static int	soreceive_rcvoob(struct socket *so, struct uio *uio,
164 		    int flags);
165 static void	so_rdknl_lock(void *);
166 static void	so_rdknl_unlock(void *);
167 static void	so_rdknl_assert_lock(void *, int);
168 static void	so_wrknl_lock(void *);
169 static void	so_wrknl_unlock(void *);
170 static void	so_wrknl_assert_lock(void *, int);
171 
172 static void	filt_sordetach(struct knote *kn);
173 static int	filt_soread(struct knote *kn, long hint);
174 static void	filt_sowdetach(struct knote *kn);
175 static int	filt_sowrite(struct knote *kn, long hint);
176 static int	filt_soempty(struct knote *kn, long hint);
177 static int inline hhook_run_socket(struct socket *so, void *hctx, int32_t h_id);
178 fo_kqfilter_t	soo_kqfilter;
179 
180 static struct filterops soread_filtops = {
181 	.f_isfd = 1,
182 	.f_detach = filt_sordetach,
183 	.f_event = filt_soread,
184 };
185 static struct filterops sowrite_filtops = {
186 	.f_isfd = 1,
187 	.f_detach = filt_sowdetach,
188 	.f_event = filt_sowrite,
189 };
190 static struct filterops soempty_filtops = {
191 	.f_isfd = 1,
192 	.f_detach = filt_sowdetach,
193 	.f_event = filt_soempty,
194 };
195 
196 so_gen_t	so_gencnt;	/* generation count for sockets */
197 
198 MALLOC_DEFINE(M_SONAME, "soname", "socket name");
199 MALLOC_DEFINE(M_PCB, "pcb", "protocol control block");
200 
201 #define	VNET_SO_ASSERT(so)						\
202 	VNET_ASSERT(curvnet != NULL,					\
203 	    ("%s:%d curvnet is NULL, so=%p", __func__, __LINE__, (so)));
204 
205 VNET_DEFINE(struct hhook_head *, socket_hhh[HHOOK_SOCKET_LAST + 1]);
206 #define	V_socket_hhh		VNET(socket_hhh)
207 
208 /*
209  * Limit on the number of connections in the listen queue waiting
210  * for accept(2).
211  * NB: The original sysctl somaxconn is still available but hidden
212  * to prevent confusion about the actual purpose of this number.
213  */
214 static u_int somaxconn = SOMAXCONN;
215 
216 static int
217 sysctl_somaxconn(SYSCTL_HANDLER_ARGS)
218 {
219 	int error;
220 	int val;
221 
222 	val = somaxconn;
223 	error = sysctl_handle_int(oidp, &val, 0, req);
224 	if (error || !req->newptr )
225 		return (error);
226 
227 	/*
228 	 * The purpose of the UINT_MAX / 3 limit, is so that the formula
229 	 *   3 * so_qlimit / 2
230 	 * below, will not overflow.
231          */
232 
233 	if (val < 1 || val > UINT_MAX / 3)
234 		return (EINVAL);
235 
236 	somaxconn = val;
237 	return (0);
238 }
239 SYSCTL_PROC(_kern_ipc, OID_AUTO, soacceptqueue,
240     CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_MPSAFE, 0, sizeof(int),
241     sysctl_somaxconn, "I",
242     "Maximum listen socket pending connection accept queue size");
243 SYSCTL_PROC(_kern_ipc, KIPC_SOMAXCONN, somaxconn,
244     CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_SKIP | CTLFLAG_MPSAFE, 0,
245     sizeof(int), sysctl_somaxconn, "I",
246     "Maximum listen socket pending connection accept queue size (compat)");
247 
248 static int numopensockets;
249 SYSCTL_INT(_kern_ipc, OID_AUTO, numopensockets, CTLFLAG_RD,
250     &numopensockets, 0, "Number of open sockets");
251 
252 /*
253  * so_global_mtx protects so_gencnt, numopensockets, and the per-socket
254  * so_gencnt field.
255  */
256 static struct mtx so_global_mtx;
257 MTX_SYSINIT(so_global_mtx, &so_global_mtx, "so_glabel", MTX_DEF);
258 
259 /*
260  * General IPC sysctl name space, used by sockets and a variety of other IPC
261  * types.
262  */
263 SYSCTL_NODE(_kern, KERN_IPC, ipc, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
264     "IPC");
265 
266 /*
267  * Initialize the socket subsystem and set up the socket
268  * memory allocator.
269  */
270 static uma_zone_t socket_zone;
271 int	maxsockets;
272 
273 static void
274 socket_zone_change(void *tag)
275 {
276 
277 	maxsockets = uma_zone_set_max(socket_zone, maxsockets);
278 }
279 
280 static void
281 socket_hhook_register(int subtype)
282 {
283 
284 	if (hhook_head_register(HHOOK_TYPE_SOCKET, subtype,
285 	    &V_socket_hhh[subtype],
286 	    HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0)
287 		printf("%s: WARNING: unable to register hook\n", __func__);
288 }
289 
290 static void
291 socket_hhook_deregister(int subtype)
292 {
293 
294 	if (hhook_head_deregister(V_socket_hhh[subtype]) != 0)
295 		printf("%s: WARNING: unable to deregister hook\n", __func__);
296 }
297 
298 static void
299 socket_init(void *tag)
300 {
301 
302 	socket_zone = uma_zcreate("socket", sizeof(struct socket), NULL, NULL,
303 	    NULL, NULL, UMA_ALIGN_PTR, 0);
304 	maxsockets = uma_zone_set_max(socket_zone, maxsockets);
305 	uma_zone_set_warning(socket_zone, "kern.ipc.maxsockets limit reached");
306 	EVENTHANDLER_REGISTER(maxsockets_change, socket_zone_change, NULL,
307 	    EVENTHANDLER_PRI_FIRST);
308 }
309 SYSINIT(socket, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY, socket_init, NULL);
310 
311 static void
312 socket_vnet_init(const void *unused __unused)
313 {
314 	int i;
315 
316 	/* We expect a contiguous range */
317 	for (i = 0; i <= HHOOK_SOCKET_LAST; i++)
318 		socket_hhook_register(i);
319 }
320 VNET_SYSINIT(socket_vnet_init, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY,
321     socket_vnet_init, NULL);
322 
323 static void
324 socket_vnet_uninit(const void *unused __unused)
325 {
326 	int i;
327 
328 	for (i = 0; i <= HHOOK_SOCKET_LAST; i++)
329 		socket_hhook_deregister(i);
330 }
331 VNET_SYSUNINIT(socket_vnet_uninit, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY,
332     socket_vnet_uninit, NULL);
333 
334 /*
335  * Initialise maxsockets.  This SYSINIT must be run after
336  * tunable_mbinit().
337  */
338 static void
339 init_maxsockets(void *ignored)
340 {
341 
342 	TUNABLE_INT_FETCH("kern.ipc.maxsockets", &maxsockets);
343 	maxsockets = imax(maxsockets, maxfiles);
344 }
345 SYSINIT(param, SI_SUB_TUNABLES, SI_ORDER_ANY, init_maxsockets, NULL);
346 
347 /*
348  * Sysctl to get and set the maximum global sockets limit.  Notify protocols
349  * of the change so that they can update their dependent limits as required.
350  */
351 static int
352 sysctl_maxsockets(SYSCTL_HANDLER_ARGS)
353 {
354 	int error, newmaxsockets;
355 
356 	newmaxsockets = maxsockets;
357 	error = sysctl_handle_int(oidp, &newmaxsockets, 0, req);
358 	if (error == 0 && req->newptr && newmaxsockets != maxsockets) {
359 		if (newmaxsockets > maxsockets &&
360 		    newmaxsockets <= maxfiles) {
361 			maxsockets = newmaxsockets;
362 			EVENTHANDLER_INVOKE(maxsockets_change);
363 		} else
364 			error = EINVAL;
365 	}
366 	return (error);
367 }
368 SYSCTL_PROC(_kern_ipc, OID_AUTO, maxsockets,
369     CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, &maxsockets, 0,
370     sysctl_maxsockets, "IU",
371     "Maximum number of sockets available");
372 
373 /*
374  * Socket operation routines.  These routines are called by the routines in
375  * sys_socket.c or from a system process, and implement the semantics of
376  * socket operations by switching out to the protocol specific routines.
377  */
378 
379 /*
380  * Get a socket structure from our zone, and initialize it.  Note that it
381  * would probably be better to allocate socket and PCB at the same time, but
382  * I'm not convinced that all the protocols can be easily modified to do
383  * this.
384  *
385  * soalloc() returns a socket with a ref count of 0.
386  */
387 static struct socket *
388 soalloc(struct vnet *vnet)
389 {
390 	struct socket *so;
391 
392 	so = uma_zalloc(socket_zone, M_NOWAIT | M_ZERO);
393 	if (so == NULL)
394 		return (NULL);
395 #ifdef MAC
396 	if (mac_socket_init(so, M_NOWAIT) != 0) {
397 		uma_zfree(socket_zone, so);
398 		return (NULL);
399 	}
400 #endif
401 	if (khelp_init_osd(HELPER_CLASS_SOCKET, &so->osd)) {
402 		uma_zfree(socket_zone, so);
403 		return (NULL);
404 	}
405 
406 	/*
407 	 * The socket locking protocol allows to lock 2 sockets at a time,
408 	 * however, the first one must be a listening socket.  WITNESS lacks
409 	 * a feature to change class of an existing lock, so we use DUPOK.
410 	 */
411 	mtx_init(&so->so_lock, "socket", NULL, MTX_DEF | MTX_DUPOK);
412 	mtx_init(&so->so_snd_mtx, "so_snd", NULL, MTX_DEF);
413 	mtx_init(&so->so_rcv_mtx, "so_rcv", NULL, MTX_DEF);
414 	so->so_rcv.sb_sel = &so->so_rdsel;
415 	so->so_snd.sb_sel = &so->so_wrsel;
416 	sx_init(&so->so_snd_sx, "so_snd_sx");
417 	sx_init(&so->so_rcv_sx, "so_rcv_sx");
418 	TAILQ_INIT(&so->so_snd.sb_aiojobq);
419 	TAILQ_INIT(&so->so_rcv.sb_aiojobq);
420 	TASK_INIT(&so->so_snd.sb_aiotask, 0, soaio_snd, so);
421 	TASK_INIT(&so->so_rcv.sb_aiotask, 0, soaio_rcv, so);
422 #ifdef VIMAGE
423 	VNET_ASSERT(vnet != NULL, ("%s:%d vnet is NULL, so=%p",
424 	    __func__, __LINE__, so));
425 	so->so_vnet = vnet;
426 #endif
427 	/* We shouldn't need the so_global_mtx */
428 	if (hhook_run_socket(so, NULL, HHOOK_SOCKET_CREATE)) {
429 		/* Do we need more comprehensive error returns? */
430 		uma_zfree(socket_zone, so);
431 		return (NULL);
432 	}
433 	mtx_lock(&so_global_mtx);
434 	so->so_gencnt = ++so_gencnt;
435 	++numopensockets;
436 #ifdef VIMAGE
437 	vnet->vnet_sockcnt++;
438 #endif
439 	mtx_unlock(&so_global_mtx);
440 
441 	return (so);
442 }
443 
444 /*
445  * Free the storage associated with a socket at the socket layer, tear down
446  * locks, labels, etc.  All protocol state is assumed already to have been
447  * torn down (and possibly never set up) by the caller.
448  */
449 void
450 sodealloc(struct socket *so)
451 {
452 
453 	KASSERT(so->so_count == 0, ("sodealloc(): so_count %d", so->so_count));
454 	KASSERT(so->so_pcb == NULL, ("sodealloc(): so_pcb != NULL"));
455 
456 	mtx_lock(&so_global_mtx);
457 	so->so_gencnt = ++so_gencnt;
458 	--numopensockets;	/* Could be below, but faster here. */
459 #ifdef VIMAGE
460 	VNET_ASSERT(so->so_vnet != NULL, ("%s:%d so_vnet is NULL, so=%p",
461 	    __func__, __LINE__, so));
462 	so->so_vnet->vnet_sockcnt--;
463 #endif
464 	mtx_unlock(&so_global_mtx);
465 #ifdef MAC
466 	mac_socket_destroy(so);
467 #endif
468 	hhook_run_socket(so, NULL, HHOOK_SOCKET_CLOSE);
469 
470 	khelp_destroy_osd(&so->osd);
471 	if (SOLISTENING(so)) {
472 		if (so->sol_accept_filter != NULL)
473 			accept_filt_setopt(so, NULL);
474 	} else {
475 		if (so->so_rcv.sb_hiwat)
476 			(void)chgsbsize(so->so_cred->cr_uidinfo,
477 			    &so->so_rcv.sb_hiwat, 0, RLIM_INFINITY);
478 		if (so->so_snd.sb_hiwat)
479 			(void)chgsbsize(so->so_cred->cr_uidinfo,
480 			    &so->so_snd.sb_hiwat, 0, RLIM_INFINITY);
481 		sx_destroy(&so->so_snd_sx);
482 		sx_destroy(&so->so_rcv_sx);
483 		mtx_destroy(&so->so_snd_mtx);
484 		mtx_destroy(&so->so_rcv_mtx);
485 	}
486 	crfree(so->so_cred);
487 	mtx_destroy(&so->so_lock);
488 	uma_zfree(socket_zone, so);
489 }
490 
491 /*
492  * socreate returns a socket with a ref count of 1 and a file descriptor
493  * reference.  The socket should be closed with soclose().
494  */
495 int
496 socreate(int dom, struct socket **aso, int type, int proto,
497     struct ucred *cred, struct thread *td)
498 {
499 	struct protosw *prp;
500 	struct socket *so;
501 	int error;
502 
503 	/*
504 	 * XXX: divert(4) historically abused PF_INET.  Keep this compatibility
505 	 * shim until all applications have been updated.
506 	 */
507 	if (__predict_false(dom == PF_INET && type == SOCK_RAW &&
508 	    proto == IPPROTO_DIVERT)) {
509 		dom = PF_DIVERT;
510 		printf("%s uses obsolete way to create divert(4) socket\n",
511 		    td->td_proc->p_comm);
512 	}
513 
514 	prp = pffindproto(dom, type, proto);
515 	if (prp == NULL) {
516 		/* No support for domain. */
517 		if (pffinddomain(dom) == NULL)
518 			return (EAFNOSUPPORT);
519 		/* No support for socket type. */
520 		if (proto == 0 && type != 0)
521 			return (EPROTOTYPE);
522 		return (EPROTONOSUPPORT);
523 	}
524 
525 	MPASS(prp->pr_attach);
526 
527 	if (IN_CAPABILITY_MODE(td) && (prp->pr_flags & PR_CAPATTACH) == 0)
528 		return (ECAPMODE);
529 
530 	if (prison_check_af(cred, prp->pr_domain->dom_family) != 0)
531 		return (EPROTONOSUPPORT);
532 
533 	so = soalloc(CRED_TO_VNET(cred));
534 	if (so == NULL)
535 		return (ENOBUFS);
536 
537 	so->so_type = type;
538 	so->so_cred = crhold(cred);
539 	if ((prp->pr_domain->dom_family == PF_INET) ||
540 	    (prp->pr_domain->dom_family == PF_INET6) ||
541 	    (prp->pr_domain->dom_family == PF_ROUTE))
542 		so->so_fibnum = td->td_proc->p_fibnum;
543 	else
544 		so->so_fibnum = 0;
545 	so->so_proto = prp;
546 #ifdef MAC
547 	mac_socket_create(cred, so);
548 #endif
549 	knlist_init(&so->so_rdsel.si_note, so, so_rdknl_lock, so_rdknl_unlock,
550 	    so_rdknl_assert_lock);
551 	knlist_init(&so->so_wrsel.si_note, so, so_wrknl_lock, so_wrknl_unlock,
552 	    so_wrknl_assert_lock);
553 	if ((prp->pr_flags & PR_SOCKBUF) == 0) {
554 		so->so_snd.sb_mtx = &so->so_snd_mtx;
555 		so->so_rcv.sb_mtx = &so->so_rcv_mtx;
556 	}
557 	/*
558 	 * Auto-sizing of socket buffers is managed by the protocols and
559 	 * the appropriate flags must be set in the pru_attach function.
560 	 */
561 	CURVNET_SET(so->so_vnet);
562 	error = prp->pr_attach(so, proto, td);
563 	CURVNET_RESTORE();
564 	if (error) {
565 		sodealloc(so);
566 		return (error);
567 	}
568 	soref(so);
569 	*aso = so;
570 	return (0);
571 }
572 
573 #ifdef REGRESSION
574 static int regression_sonewconn_earlytest = 1;
575 SYSCTL_INT(_regression, OID_AUTO, sonewconn_earlytest, CTLFLAG_RW,
576     &regression_sonewconn_earlytest, 0, "Perform early sonewconn limit test");
577 #endif
578 
579 static int sooverprio = LOG_DEBUG;
580 SYSCTL_INT(_kern_ipc, OID_AUTO, sooverprio, CTLFLAG_RW,
581     &sooverprio, 0, "Log priority for listen socket overflows: 0..7 or -1 to disable");
582 
583 static struct timeval overinterval = { 60, 0 };
584 SYSCTL_TIMEVAL_SEC(_kern_ipc, OID_AUTO, sooverinterval, CTLFLAG_RW,
585     &overinterval,
586     "Delay in seconds between warnings for listen socket overflows");
587 
588 /*
589  * When an attempt at a new connection is noted on a socket which supports
590  * accept(2), the protocol has two options:
591  * 1) Call legacy sonewconn() function, which would call protocol attach
592  *    method, same as used for socket(2).
593  * 2) Call solisten_clone(), do attach that is specific to a cloned connection,
594  *    and then call solisten_enqueue().
595  *
596  * Note: the ref count on the socket is 0 on return.
597  */
598 struct socket *
599 solisten_clone(struct socket *head)
600 {
601 	struct sbuf descrsb;
602 	struct socket *so;
603 	int len, overcount;
604 	u_int qlen;
605 	const char localprefix[] = "local:";
606 	char descrbuf[SUNPATHLEN + sizeof(localprefix)];
607 #if defined(INET6)
608 	char addrbuf[INET6_ADDRSTRLEN];
609 #elif defined(INET)
610 	char addrbuf[INET_ADDRSTRLEN];
611 #endif
612 	bool dolog, over;
613 
614 	SOLISTEN_LOCK(head);
615 	over = (head->sol_qlen > 3 * head->sol_qlimit / 2);
616 #ifdef REGRESSION
617 	if (regression_sonewconn_earlytest && over) {
618 #else
619 	if (over) {
620 #endif
621 		head->sol_overcount++;
622 		dolog = (sooverprio >= 0) &&
623 			!!ratecheck(&head->sol_lastover, &overinterval);
624 
625 		/*
626 		 * If we're going to log, copy the overflow count and queue
627 		 * length from the listen socket before dropping the lock.
628 		 * Also, reset the overflow count.
629 		 */
630 		if (dolog) {
631 			overcount = head->sol_overcount;
632 			head->sol_overcount = 0;
633 			qlen = head->sol_qlen;
634 		}
635 		SOLISTEN_UNLOCK(head);
636 
637 		if (dolog) {
638 			/*
639 			 * Try to print something descriptive about the
640 			 * socket for the error message.
641 			 */
642 			sbuf_new(&descrsb, descrbuf, sizeof(descrbuf),
643 			    SBUF_FIXEDLEN);
644 			switch (head->so_proto->pr_domain->dom_family) {
645 #if defined(INET) || defined(INET6)
646 #ifdef INET
647 			case AF_INET:
648 #endif
649 #ifdef INET6
650 			case AF_INET6:
651 				if (head->so_proto->pr_domain->dom_family ==
652 				    AF_INET6 ||
653 				    (sotoinpcb(head)->inp_inc.inc_flags &
654 				    INC_ISIPV6)) {
655 					ip6_sprintf(addrbuf,
656 					    &sotoinpcb(head)->inp_inc.inc6_laddr);
657 					sbuf_printf(&descrsb, "[%s]", addrbuf);
658 				} else
659 #endif
660 				{
661 #ifdef INET
662 					inet_ntoa_r(
663 					    sotoinpcb(head)->inp_inc.inc_laddr,
664 					    addrbuf);
665 					sbuf_cat(&descrsb, addrbuf);
666 #endif
667 				}
668 				sbuf_printf(&descrsb, ":%hu (proto %u)",
669 				    ntohs(sotoinpcb(head)->inp_inc.inc_lport),
670 				    head->so_proto->pr_protocol);
671 				break;
672 #endif /* INET || INET6 */
673 			case AF_UNIX:
674 				sbuf_cat(&descrsb, localprefix);
675 				if (sotounpcb(head)->unp_addr != NULL)
676 					len =
677 					    sotounpcb(head)->unp_addr->sun_len -
678 					    offsetof(struct sockaddr_un,
679 					    sun_path);
680 				else
681 					len = 0;
682 				if (len > 0)
683 					sbuf_bcat(&descrsb,
684 					    sotounpcb(head)->unp_addr->sun_path,
685 					    len);
686 				else
687 					sbuf_cat(&descrsb, "(unknown)");
688 				break;
689 			}
690 
691 			/*
692 			 * If we can't print something more specific, at least
693 			 * print the domain name.
694 			 */
695 			if (sbuf_finish(&descrsb) != 0 ||
696 			    sbuf_len(&descrsb) <= 0) {
697 				sbuf_clear(&descrsb);
698 				sbuf_cat(&descrsb,
699 				    head->so_proto->pr_domain->dom_name ?:
700 				    "unknown");
701 				sbuf_finish(&descrsb);
702 			}
703 			KASSERT(sbuf_len(&descrsb) > 0,
704 			    ("%s: sbuf creation failed", __func__));
705 			/*
706 			 * Preserve the historic listen queue overflow log
707 			 * message, that starts with "sonewconn:".  It has
708 			 * been known to sysadmins for years and also test
709 			 * sys/kern/sonewconn_overflow checks for it.
710 			 */
711 			if (head->so_cred == 0) {
712 				log(LOG_PRI(sooverprio),
713 				    "sonewconn: pcb %p (%s): "
714 				    "Listen queue overflow: %i already in "
715 				    "queue awaiting acceptance (%d "
716 				    "occurrences)\n", head->so_pcb,
717 				    sbuf_data(&descrsb),
718 			    	qlen, overcount);
719 			} else {
720 				log(LOG_PRI(sooverprio),
721 				    "sonewconn: pcb %p (%s): "
722 				    "Listen queue overflow: "
723 				    "%i already in queue awaiting acceptance "
724 				    "(%d occurrences), euid %d, rgid %d, jail %s\n",
725 				    head->so_pcb, sbuf_data(&descrsb), qlen,
726 				    overcount, head->so_cred->cr_uid,
727 				    head->so_cred->cr_rgid,
728 				    head->so_cred->cr_prison ?
729 					head->so_cred->cr_prison->pr_name :
730 					"not_jailed");
731 			}
732 			sbuf_delete(&descrsb);
733 
734 			overcount = 0;
735 		}
736 
737 		return (NULL);
738 	}
739 	SOLISTEN_UNLOCK(head);
740 	VNET_ASSERT(head->so_vnet != NULL, ("%s: so %p vnet is NULL",
741 	    __func__, head));
742 	so = soalloc(head->so_vnet);
743 	if (so == NULL) {
744 		log(LOG_DEBUG, "%s: pcb %p: New socket allocation failure: "
745 		    "limit reached or out of memory\n",
746 		    __func__, head->so_pcb);
747 		return (NULL);
748 	}
749 	so->so_listen = head;
750 	so->so_type = head->so_type;
751 	/*
752 	 * POSIX is ambiguous on what options an accept(2)ed socket should
753 	 * inherit from the listener.  Words "create a new socket" may be
754 	 * interpreted as not inheriting anything.  Best programming practice
755 	 * for application developers is to not rely on such inheritance.
756 	 * FreeBSD had historically inherited all so_options excluding
757 	 * SO_ACCEPTCONN, which virtually means all SOL_SOCKET level options,
758 	 * including those completely irrelevant to a new born socket.  For
759 	 * compatibility with older versions we will inherit a list of
760 	 * meaningful options.
761 	 */
762 	so->so_options = head->so_options & (SO_KEEPALIVE | SO_DONTROUTE |
763 	    SO_LINGER | SO_OOBINLINE | SO_NOSIGPIPE);
764 	so->so_linger = head->so_linger;
765 	so->so_state = head->so_state;
766 	so->so_fibnum = head->so_fibnum;
767 	so->so_proto = head->so_proto;
768 	so->so_cred = crhold(head->so_cred);
769 #ifdef MAC
770 	mac_socket_newconn(head, so);
771 #endif
772 	knlist_init(&so->so_rdsel.si_note, so, so_rdknl_lock, so_rdknl_unlock,
773 	    so_rdknl_assert_lock);
774 	knlist_init(&so->so_wrsel.si_note, so, so_wrknl_lock, so_wrknl_unlock,
775 	    so_wrknl_assert_lock);
776 	VNET_SO_ASSERT(head);
777 	if (soreserve(so, head->sol_sbsnd_hiwat, head->sol_sbrcv_hiwat)) {
778 		sodealloc(so);
779 		log(LOG_DEBUG, "%s: pcb %p: soreserve() failed\n",
780 		    __func__, head->so_pcb);
781 		return (NULL);
782 	}
783 	so->so_rcv.sb_lowat = head->sol_sbrcv_lowat;
784 	so->so_snd.sb_lowat = head->sol_sbsnd_lowat;
785 	so->so_rcv.sb_timeo = head->sol_sbrcv_timeo;
786 	so->so_snd.sb_timeo = head->sol_sbsnd_timeo;
787 	so->so_rcv.sb_flags = head->sol_sbrcv_flags & SB_AUTOSIZE;
788 	so->so_snd.sb_flags = head->sol_sbsnd_flags & SB_AUTOSIZE;
789 	if ((so->so_proto->pr_flags & PR_SOCKBUF) == 0) {
790 		so->so_snd.sb_mtx = &so->so_snd_mtx;
791 		so->so_rcv.sb_mtx = &so->so_rcv_mtx;
792 	}
793 
794 	return (so);
795 }
796 
797 /* Connstatus may be 0, or SS_ISCONFIRMING, or SS_ISCONNECTED. */
798 struct socket *
799 sonewconn(struct socket *head, int connstatus)
800 {
801 	struct socket *so;
802 
803 	if ((so = solisten_clone(head)) == NULL)
804 		return (NULL);
805 
806 	if (so->so_proto->pr_attach(so, 0, NULL) != 0) {
807 		sodealloc(so);
808 		log(LOG_DEBUG, "%s: pcb %p: pr_attach() failed\n",
809 		    __func__, head->so_pcb);
810 		return (NULL);
811 	}
812 
813 	(void)solisten_enqueue(so, connstatus);
814 
815 	return (so);
816 }
817 
818 /*
819  * Enqueue socket cloned by solisten_clone() to the listen queue of the
820  * listener it has been cloned from.
821  *
822  * Return 'true' if socket landed on complete queue, otherwise 'false'.
823  */
824 bool
825 solisten_enqueue(struct socket *so, int connstatus)
826 {
827 	struct socket *head = so->so_listen;
828 
829 	MPASS(refcount_load(&so->so_count) == 0);
830 	refcount_init(&so->so_count, 1);
831 
832 	SOLISTEN_LOCK(head);
833 	if (head->sol_accept_filter != NULL)
834 		connstatus = 0;
835 	so->so_state |= connstatus;
836 	soref(head); /* A socket on (in)complete queue refs head. */
837 	if (connstatus) {
838 		TAILQ_INSERT_TAIL(&head->sol_comp, so, so_list);
839 		so->so_qstate = SQ_COMP;
840 		head->sol_qlen++;
841 		solisten_wakeup(head);	/* unlocks */
842 		return (true);
843 	} else {
844 		/*
845 		 * Keep removing sockets from the head until there's room for
846 		 * us to insert on the tail.  In pre-locking revisions, this
847 		 * was a simple if(), but as we could be racing with other
848 		 * threads and soabort() requires dropping locks, we must
849 		 * loop waiting for the condition to be true.
850 		 */
851 		while (head->sol_incqlen > head->sol_qlimit) {
852 			struct socket *sp;
853 
854 			sp = TAILQ_FIRST(&head->sol_incomp);
855 			TAILQ_REMOVE(&head->sol_incomp, sp, so_list);
856 			head->sol_incqlen--;
857 			SOCK_LOCK(sp);
858 			sp->so_qstate = SQ_NONE;
859 			sp->so_listen = NULL;
860 			SOCK_UNLOCK(sp);
861 			sorele_locked(head);	/* does SOLISTEN_UNLOCK, head stays */
862 			soabort(sp);
863 			SOLISTEN_LOCK(head);
864 		}
865 		TAILQ_INSERT_TAIL(&head->sol_incomp, so, so_list);
866 		so->so_qstate = SQ_INCOMP;
867 		head->sol_incqlen++;
868 		SOLISTEN_UNLOCK(head);
869 		return (false);
870 	}
871 }
872 
873 #if defined(SCTP) || defined(SCTP_SUPPORT)
874 /*
875  * Socket part of sctp_peeloff().  Detach a new socket from an
876  * association.  The new socket is returned with a reference.
877  *
878  * XXXGL: reduce copy-paste with solisten_clone().
879  */
880 struct socket *
881 sopeeloff(struct socket *head)
882 {
883 	struct socket *so;
884 
885 	VNET_ASSERT(head->so_vnet != NULL, ("%s:%d so_vnet is NULL, head=%p",
886 	    __func__, __LINE__, head));
887 	so = soalloc(head->so_vnet);
888 	if (so == NULL) {
889 		log(LOG_DEBUG, "%s: pcb %p: New socket allocation failure: "
890 		    "limit reached or out of memory\n",
891 		    __func__, head->so_pcb);
892 		return (NULL);
893 	}
894 	so->so_type = head->so_type;
895 	so->so_options = head->so_options;
896 	so->so_linger = head->so_linger;
897 	so->so_state = (head->so_state & SS_NBIO) | SS_ISCONNECTED;
898 	so->so_fibnum = head->so_fibnum;
899 	so->so_proto = head->so_proto;
900 	so->so_cred = crhold(head->so_cred);
901 #ifdef MAC
902 	mac_socket_newconn(head, so);
903 #endif
904 	knlist_init(&so->so_rdsel.si_note, so, so_rdknl_lock, so_rdknl_unlock,
905 	    so_rdknl_assert_lock);
906 	knlist_init(&so->so_wrsel.si_note, so, so_wrknl_lock, so_wrknl_unlock,
907 	    so_wrknl_assert_lock);
908 	VNET_SO_ASSERT(head);
909 	if (soreserve(so, head->so_snd.sb_hiwat, head->so_rcv.sb_hiwat)) {
910 		sodealloc(so);
911 		log(LOG_DEBUG, "%s: pcb %p: soreserve() failed\n",
912 		    __func__, head->so_pcb);
913 		return (NULL);
914 	}
915 	if ((*so->so_proto->pr_attach)(so, 0, NULL)) {
916 		sodealloc(so);
917 		log(LOG_DEBUG, "%s: pcb %p: pru_attach() failed\n",
918 		    __func__, head->so_pcb);
919 		return (NULL);
920 	}
921 	so->so_rcv.sb_lowat = head->so_rcv.sb_lowat;
922 	so->so_snd.sb_lowat = head->so_snd.sb_lowat;
923 	so->so_rcv.sb_timeo = head->so_rcv.sb_timeo;
924 	so->so_snd.sb_timeo = head->so_snd.sb_timeo;
925 	so->so_rcv.sb_flags |= head->so_rcv.sb_flags & SB_AUTOSIZE;
926 	so->so_snd.sb_flags |= head->so_snd.sb_flags & SB_AUTOSIZE;
927 
928 	soref(so);
929 
930 	return (so);
931 }
932 #endif	/* SCTP */
933 
934 int
935 sobind(struct socket *so, struct sockaddr *nam, struct thread *td)
936 {
937 	int error;
938 
939 	CURVNET_SET(so->so_vnet);
940 	error = so->so_proto->pr_bind(so, nam, td);
941 	CURVNET_RESTORE();
942 	return (error);
943 }
944 
945 int
946 sobindat(int fd, struct socket *so, struct sockaddr *nam, struct thread *td)
947 {
948 	int error;
949 
950 	CURVNET_SET(so->so_vnet);
951 	error = so->so_proto->pr_bindat(fd, so, nam, td);
952 	CURVNET_RESTORE();
953 	return (error);
954 }
955 
956 /*
957  * solisten() transitions a socket from a non-listening state to a listening
958  * state, but can also be used to update the listen queue depth on an
959  * existing listen socket.  The protocol will call back into the sockets
960  * layer using solisten_proto_check() and solisten_proto() to check and set
961  * socket-layer listen state.  Call backs are used so that the protocol can
962  * acquire both protocol and socket layer locks in whatever order is required
963  * by the protocol.
964  *
965  * Protocol implementors are advised to hold the socket lock across the
966  * socket-layer test and set to avoid races at the socket layer.
967  */
968 int
969 solisten(struct socket *so, int backlog, struct thread *td)
970 {
971 	int error;
972 
973 	CURVNET_SET(so->so_vnet);
974 	error = so->so_proto->pr_listen(so, backlog, td);
975 	CURVNET_RESTORE();
976 	return (error);
977 }
978 
979 /*
980  * Prepare for a call to solisten_proto().  Acquire all socket buffer locks in
981  * order to interlock with socket I/O.
982  */
983 int
984 solisten_proto_check(struct socket *so)
985 {
986 	SOCK_LOCK_ASSERT(so);
987 
988 	if ((so->so_state & (SS_ISCONNECTED | SS_ISCONNECTING |
989 	    SS_ISDISCONNECTING)) != 0)
990 		return (EINVAL);
991 
992 	/*
993 	 * Sleeping is not permitted here, so simply fail if userspace is
994 	 * attempting to transmit or receive on the socket.  This kind of
995 	 * transient failure is not ideal, but it should occur only if userspace
996 	 * is misusing the socket interfaces.
997 	 */
998 	if (!sx_try_xlock(&so->so_snd_sx))
999 		return (EAGAIN);
1000 	if (!sx_try_xlock(&so->so_rcv_sx)) {
1001 		sx_xunlock(&so->so_snd_sx);
1002 		return (EAGAIN);
1003 	}
1004 	mtx_lock(&so->so_snd_mtx);
1005 	mtx_lock(&so->so_rcv_mtx);
1006 
1007 	/* Interlock with soo_aio_queue() and KTLS. */
1008 	if (!SOLISTENING(so)) {
1009 		bool ktls;
1010 
1011 #ifdef KERN_TLS
1012 		ktls = so->so_snd.sb_tls_info != NULL ||
1013 		    so->so_rcv.sb_tls_info != NULL;
1014 #else
1015 		ktls = false;
1016 #endif
1017 		if (ktls ||
1018 		    (so->so_snd.sb_flags & (SB_AIO | SB_AIO_RUNNING)) != 0 ||
1019 		    (so->so_rcv.sb_flags & (SB_AIO | SB_AIO_RUNNING)) != 0) {
1020 			solisten_proto_abort(so);
1021 			return (EINVAL);
1022 		}
1023 	}
1024 
1025 	return (0);
1026 }
1027 
1028 /*
1029  * Undo the setup done by solisten_proto_check().
1030  */
1031 void
1032 solisten_proto_abort(struct socket *so)
1033 {
1034 	mtx_unlock(&so->so_snd_mtx);
1035 	mtx_unlock(&so->so_rcv_mtx);
1036 	sx_xunlock(&so->so_snd_sx);
1037 	sx_xunlock(&so->so_rcv_sx);
1038 }
1039 
1040 void
1041 solisten_proto(struct socket *so, int backlog)
1042 {
1043 	int sbrcv_lowat, sbsnd_lowat;
1044 	u_int sbrcv_hiwat, sbsnd_hiwat;
1045 	short sbrcv_flags, sbsnd_flags;
1046 	sbintime_t sbrcv_timeo, sbsnd_timeo;
1047 
1048 	SOCK_LOCK_ASSERT(so);
1049 	KASSERT((so->so_state & (SS_ISCONNECTED | SS_ISCONNECTING |
1050 	    SS_ISDISCONNECTING)) == 0,
1051 	    ("%s: bad socket state %p", __func__, so));
1052 
1053 	if (SOLISTENING(so))
1054 		goto listening;
1055 
1056 	/*
1057 	 * Change this socket to listening state.
1058 	 */
1059 	sbrcv_lowat = so->so_rcv.sb_lowat;
1060 	sbsnd_lowat = so->so_snd.sb_lowat;
1061 	sbrcv_hiwat = so->so_rcv.sb_hiwat;
1062 	sbsnd_hiwat = so->so_snd.sb_hiwat;
1063 	sbrcv_flags = so->so_rcv.sb_flags;
1064 	sbsnd_flags = so->so_snd.sb_flags;
1065 	sbrcv_timeo = so->so_rcv.sb_timeo;
1066 	sbsnd_timeo = so->so_snd.sb_timeo;
1067 
1068 	sbdestroy(so, SO_SND);
1069 	sbdestroy(so, SO_RCV);
1070 
1071 #ifdef INVARIANTS
1072 	bzero(&so->so_rcv,
1073 	    sizeof(struct socket) - offsetof(struct socket, so_rcv));
1074 #endif
1075 
1076 	so->sol_sbrcv_lowat = sbrcv_lowat;
1077 	so->sol_sbsnd_lowat = sbsnd_lowat;
1078 	so->sol_sbrcv_hiwat = sbrcv_hiwat;
1079 	so->sol_sbsnd_hiwat = sbsnd_hiwat;
1080 	so->sol_sbrcv_flags = sbrcv_flags;
1081 	so->sol_sbsnd_flags = sbsnd_flags;
1082 	so->sol_sbrcv_timeo = sbrcv_timeo;
1083 	so->sol_sbsnd_timeo = sbsnd_timeo;
1084 
1085 	so->sol_qlen = so->sol_incqlen = 0;
1086 	TAILQ_INIT(&so->sol_incomp);
1087 	TAILQ_INIT(&so->sol_comp);
1088 
1089 	so->sol_accept_filter = NULL;
1090 	so->sol_accept_filter_arg = NULL;
1091 	so->sol_accept_filter_str = NULL;
1092 
1093 	so->sol_upcall = NULL;
1094 	so->sol_upcallarg = NULL;
1095 
1096 	so->so_options |= SO_ACCEPTCONN;
1097 
1098 listening:
1099 	if (backlog < 0 || backlog > somaxconn)
1100 		backlog = somaxconn;
1101 	so->sol_qlimit = backlog;
1102 
1103 	mtx_unlock(&so->so_snd_mtx);
1104 	mtx_unlock(&so->so_rcv_mtx);
1105 	sx_xunlock(&so->so_snd_sx);
1106 	sx_xunlock(&so->so_rcv_sx);
1107 }
1108 
1109 /*
1110  * Wakeup listeners/subsystems once we have a complete connection.
1111  * Enters with lock, returns unlocked.
1112  */
1113 void
1114 solisten_wakeup(struct socket *sol)
1115 {
1116 
1117 	if (sol->sol_upcall != NULL)
1118 		(void )sol->sol_upcall(sol, sol->sol_upcallarg, M_NOWAIT);
1119 	else {
1120 		selwakeuppri(&sol->so_rdsel, PSOCK);
1121 		KNOTE_LOCKED(&sol->so_rdsel.si_note, 0);
1122 	}
1123 	SOLISTEN_UNLOCK(sol);
1124 	wakeup_one(&sol->sol_comp);
1125 	if ((sol->so_state & SS_ASYNC) && sol->so_sigio != NULL)
1126 		pgsigio(&sol->so_sigio, SIGIO, 0);
1127 }
1128 
1129 /*
1130  * Return single connection off a listening socket queue.  Main consumer of
1131  * the function is kern_accept4().  Some modules, that do their own accept
1132  * management also use the function.  The socket reference held by the
1133  * listen queue is handed to the caller.
1134  *
1135  * Listening socket must be locked on entry and is returned unlocked on
1136  * return.
1137  * The flags argument is set of accept4(2) flags and ACCEPT4_INHERIT.
1138  */
1139 int
1140 solisten_dequeue(struct socket *head, struct socket **ret, int flags)
1141 {
1142 	struct socket *so;
1143 	int error;
1144 
1145 	SOLISTEN_LOCK_ASSERT(head);
1146 
1147 	while (!(head->so_state & SS_NBIO) && TAILQ_EMPTY(&head->sol_comp) &&
1148 	    head->so_error == 0) {
1149 		error = msleep(&head->sol_comp, SOCK_MTX(head), PSOCK | PCATCH,
1150 		    "accept", 0);
1151 		if (error != 0) {
1152 			SOLISTEN_UNLOCK(head);
1153 			return (error);
1154 		}
1155 	}
1156 	if (head->so_error) {
1157 		error = head->so_error;
1158 		head->so_error = 0;
1159 	} else if ((head->so_state & SS_NBIO) && TAILQ_EMPTY(&head->sol_comp))
1160 		error = EWOULDBLOCK;
1161 	else
1162 		error = 0;
1163 	if (error) {
1164 		SOLISTEN_UNLOCK(head);
1165 		return (error);
1166 	}
1167 	so = TAILQ_FIRST(&head->sol_comp);
1168 	SOCK_LOCK(so);
1169 	KASSERT(so->so_qstate == SQ_COMP,
1170 	    ("%s: so %p not SQ_COMP", __func__, so));
1171 	head->sol_qlen--;
1172 	so->so_qstate = SQ_NONE;
1173 	so->so_listen = NULL;
1174 	TAILQ_REMOVE(&head->sol_comp, so, so_list);
1175 	if (flags & ACCEPT4_INHERIT)
1176 		so->so_state |= (head->so_state & SS_NBIO);
1177 	else
1178 		so->so_state |= (flags & SOCK_NONBLOCK) ? SS_NBIO : 0;
1179 	SOCK_UNLOCK(so);
1180 	sorele_locked(head);
1181 
1182 	*ret = so;
1183 	return (0);
1184 }
1185 
1186 /*
1187  * Free socket upon release of the very last reference.
1188  */
1189 static void
1190 sofree(struct socket *so)
1191 {
1192 	struct protosw *pr = so->so_proto;
1193 
1194 	SOCK_LOCK_ASSERT(so);
1195 	KASSERT(refcount_load(&so->so_count) == 0,
1196 	    ("%s: so %p has references", __func__, so));
1197 	KASSERT(SOLISTENING(so) || so->so_qstate == SQ_NONE,
1198 	    ("%s: so %p is on listen queue", __func__, so));
1199 
1200 	SOCK_UNLOCK(so);
1201 
1202 	if (so->so_dtor != NULL)
1203 		so->so_dtor(so);
1204 
1205 	VNET_SO_ASSERT(so);
1206 	if ((pr->pr_flags & PR_RIGHTS) && !SOLISTENING(so)) {
1207 		MPASS(pr->pr_domain->dom_dispose != NULL);
1208 		(*pr->pr_domain->dom_dispose)(so);
1209 	}
1210 	if (pr->pr_detach != NULL)
1211 		pr->pr_detach(so);
1212 
1213 	/*
1214 	 * From this point on, we assume that no other references to this
1215 	 * socket exist anywhere else in the stack.  Therefore, no locks need
1216 	 * to be acquired or held.
1217 	 */
1218 	if (!(pr->pr_flags & PR_SOCKBUF) && !SOLISTENING(so)) {
1219 		sbdestroy(so, SO_SND);
1220 		sbdestroy(so, SO_RCV);
1221 	}
1222 	seldrain(&so->so_rdsel);
1223 	seldrain(&so->so_wrsel);
1224 	knlist_destroy(&so->so_rdsel.si_note);
1225 	knlist_destroy(&so->so_wrsel.si_note);
1226 	sodealloc(so);
1227 }
1228 
1229 /*
1230  * Release a reference on a socket while holding the socket lock.
1231  * Unlocks the socket lock before returning.
1232  */
1233 void
1234 sorele_locked(struct socket *so)
1235 {
1236 	SOCK_LOCK_ASSERT(so);
1237 	if (refcount_release(&so->so_count))
1238 		sofree(so);
1239 	else
1240 		SOCK_UNLOCK(so);
1241 }
1242 
1243 /*
1244  * Close a socket on last file table reference removal.  Initiate disconnect
1245  * if connected.  Free socket when disconnect complete.
1246  *
1247  * This function will sorele() the socket.  Note that soclose() may be called
1248  * prior to the ref count reaching zero.  The actual socket structure will
1249  * not be freed until the ref count reaches zero.
1250  */
1251 int
1252 soclose(struct socket *so)
1253 {
1254 	struct accept_queue lqueue;
1255 	int error = 0;
1256 	bool listening, last __diagused;
1257 
1258 	CURVNET_SET(so->so_vnet);
1259 	funsetown(&so->so_sigio);
1260 	if (so->so_state & SS_ISCONNECTED) {
1261 		if ((so->so_state & SS_ISDISCONNECTING) == 0) {
1262 			error = sodisconnect(so);
1263 			if (error) {
1264 				if (error == ENOTCONN)
1265 					error = 0;
1266 				goto drop;
1267 			}
1268 		}
1269 
1270 		if ((so->so_options & SO_LINGER) != 0 && so->so_linger != 0) {
1271 			if ((so->so_state & SS_ISDISCONNECTING) &&
1272 			    (so->so_state & SS_NBIO))
1273 				goto drop;
1274 			while (so->so_state & SS_ISCONNECTED) {
1275 				error = tsleep(&so->so_timeo,
1276 				    PSOCK | PCATCH, "soclos",
1277 				    so->so_linger * hz);
1278 				if (error)
1279 					break;
1280 			}
1281 		}
1282 	}
1283 
1284 drop:
1285 	if (so->so_proto->pr_close != NULL)
1286 		so->so_proto->pr_close(so);
1287 
1288 	SOCK_LOCK(so);
1289 	if ((listening = SOLISTENING(so))) {
1290 		struct socket *sp;
1291 
1292 		TAILQ_INIT(&lqueue);
1293 		TAILQ_SWAP(&lqueue, &so->sol_incomp, socket, so_list);
1294 		TAILQ_CONCAT(&lqueue, &so->sol_comp, so_list);
1295 
1296 		so->sol_qlen = so->sol_incqlen = 0;
1297 
1298 		TAILQ_FOREACH(sp, &lqueue, so_list) {
1299 			SOCK_LOCK(sp);
1300 			sp->so_qstate = SQ_NONE;
1301 			sp->so_listen = NULL;
1302 			SOCK_UNLOCK(sp);
1303 			last = refcount_release(&so->so_count);
1304 			KASSERT(!last, ("%s: released last reference for %p",
1305 			    __func__, so));
1306 		}
1307 	}
1308 	sorele_locked(so);
1309 	if (listening) {
1310 		struct socket *sp, *tsp;
1311 
1312 		TAILQ_FOREACH_SAFE(sp, &lqueue, so_list, tsp)
1313 			soabort(sp);
1314 	}
1315 	CURVNET_RESTORE();
1316 	return (error);
1317 }
1318 
1319 /*
1320  * soabort() is used to abruptly tear down a connection, such as when a
1321  * resource limit is reached (listen queue depth exceeded), or if a listen
1322  * socket is closed while there are sockets waiting to be accepted.
1323  *
1324  * This interface is tricky, because it is called on an unreferenced socket,
1325  * and must be called only by a thread that has actually removed the socket
1326  * from the listen queue it was on.  Likely this thread holds the last
1327  * reference on the socket and soabort() will proceed with sofree().  But
1328  * it might be not the last, as the sockets on the listen queues are seen
1329  * from the protocol side.
1330  *
1331  * This interface will call into the protocol code, so must not be called
1332  * with any socket locks held.  Protocols do call it while holding their own
1333  * recursible protocol mutexes, but this is something that should be subject
1334  * to review in the future.
1335  *
1336  * Usually socket should have a single reference left, but this is not a
1337  * requirement.  In the past, when we have had named references for file
1338  * descriptor and protocol, we asserted that none of them are being held.
1339  */
1340 void
1341 soabort(struct socket *so)
1342 {
1343 
1344 	VNET_SO_ASSERT(so);
1345 
1346 	if (so->so_proto->pr_abort != NULL)
1347 		so->so_proto->pr_abort(so);
1348 	SOCK_LOCK(so);
1349 	sorele_locked(so);
1350 }
1351 
1352 int
1353 soaccept(struct socket *so, struct sockaddr **nam)
1354 {
1355 	int error;
1356 
1357 	CURVNET_SET(so->so_vnet);
1358 	error = so->so_proto->pr_accept(so, nam);
1359 	CURVNET_RESTORE();
1360 	return (error);
1361 }
1362 
1363 int
1364 soconnect(struct socket *so, struct sockaddr *nam, struct thread *td)
1365 {
1366 
1367 	return (soconnectat(AT_FDCWD, so, nam, td));
1368 }
1369 
1370 int
1371 soconnectat(int fd, struct socket *so, struct sockaddr *nam, struct thread *td)
1372 {
1373 	int error;
1374 
1375 	CURVNET_SET(so->so_vnet);
1376 
1377 	/*
1378 	 * If protocol is connection-based, can only connect once.
1379 	 * Otherwise, if connected, try to disconnect first.  This allows
1380 	 * user to disconnect by connecting to, e.g., a null address.
1381 	 *
1382 	 * Note, this check is racy and may need to be re-evaluated at the
1383 	 * protocol layer.
1384 	 */
1385 	if (so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING) &&
1386 	    ((so->so_proto->pr_flags & PR_CONNREQUIRED) ||
1387 	    (error = sodisconnect(so)))) {
1388 		error = EISCONN;
1389 	} else {
1390 		/*
1391 		 * Prevent accumulated error from previous connection from
1392 		 * biting us.
1393 		 */
1394 		so->so_error = 0;
1395 		if (fd == AT_FDCWD) {
1396 			error = so->so_proto->pr_connect(so, nam, td);
1397 		} else {
1398 			error = so->so_proto->pr_connectat(fd, so, nam, td);
1399 		}
1400 	}
1401 	CURVNET_RESTORE();
1402 
1403 	return (error);
1404 }
1405 
1406 int
1407 soconnect2(struct socket *so1, struct socket *so2)
1408 {
1409 	int error;
1410 
1411 	CURVNET_SET(so1->so_vnet);
1412 	error = so1->so_proto->pr_connect2(so1, so2);
1413 	CURVNET_RESTORE();
1414 	return (error);
1415 }
1416 
1417 int
1418 sodisconnect(struct socket *so)
1419 {
1420 	int error;
1421 
1422 	if ((so->so_state & SS_ISCONNECTED) == 0)
1423 		return (ENOTCONN);
1424 	if (so->so_state & SS_ISDISCONNECTING)
1425 		return (EALREADY);
1426 	VNET_SO_ASSERT(so);
1427 	error = so->so_proto->pr_disconnect(so);
1428 	return (error);
1429 }
1430 
1431 int
1432 sosend_dgram(struct socket *so, struct sockaddr *addr, struct uio *uio,
1433     struct mbuf *top, struct mbuf *control, int flags, struct thread *td)
1434 {
1435 	long space;
1436 	ssize_t resid;
1437 	int clen = 0, error, dontroute;
1438 
1439 	KASSERT(so->so_type == SOCK_DGRAM, ("sosend_dgram: !SOCK_DGRAM"));
1440 	KASSERT(so->so_proto->pr_flags & PR_ATOMIC,
1441 	    ("sosend_dgram: !PR_ATOMIC"));
1442 
1443 	if (uio != NULL)
1444 		resid = uio->uio_resid;
1445 	else
1446 		resid = top->m_pkthdr.len;
1447 	/*
1448 	 * In theory resid should be unsigned.  However, space must be
1449 	 * signed, as it might be less than 0 if we over-committed, and we
1450 	 * must use a signed comparison of space and resid.  On the other
1451 	 * hand, a negative resid causes us to loop sending 0-length
1452 	 * segments to the protocol.
1453 	 */
1454 	if (resid < 0) {
1455 		error = EINVAL;
1456 		goto out;
1457 	}
1458 
1459 	dontroute =
1460 	    (flags & MSG_DONTROUTE) && (so->so_options & SO_DONTROUTE) == 0;
1461 	if (td != NULL)
1462 		td->td_ru.ru_msgsnd++;
1463 	if (control != NULL)
1464 		clen = control->m_len;
1465 
1466 	SOCKBUF_LOCK(&so->so_snd);
1467 	if (so->so_snd.sb_state & SBS_CANTSENDMORE) {
1468 		SOCKBUF_UNLOCK(&so->so_snd);
1469 		error = EPIPE;
1470 		goto out;
1471 	}
1472 	if (so->so_error) {
1473 		error = so->so_error;
1474 		so->so_error = 0;
1475 		SOCKBUF_UNLOCK(&so->so_snd);
1476 		goto out;
1477 	}
1478 	if ((so->so_state & SS_ISCONNECTED) == 0) {
1479 		/*
1480 		 * `sendto' and `sendmsg' is allowed on a connection-based
1481 		 * socket if it supports implied connect.  Return ENOTCONN if
1482 		 * not connected and no address is supplied.
1483 		 */
1484 		if ((so->so_proto->pr_flags & PR_CONNREQUIRED) &&
1485 		    (so->so_proto->pr_flags & PR_IMPLOPCL) == 0) {
1486 			if ((so->so_state & SS_ISCONFIRMING) == 0 &&
1487 			    !(resid == 0 && clen != 0)) {
1488 				SOCKBUF_UNLOCK(&so->so_snd);
1489 				error = ENOTCONN;
1490 				goto out;
1491 			}
1492 		} else if (addr == NULL) {
1493 			if (so->so_proto->pr_flags & PR_CONNREQUIRED)
1494 				error = ENOTCONN;
1495 			else
1496 				error = EDESTADDRREQ;
1497 			SOCKBUF_UNLOCK(&so->so_snd);
1498 			goto out;
1499 		}
1500 	}
1501 
1502 	/*
1503 	 * Do we need MSG_OOB support in SOCK_DGRAM?  Signs here may be a
1504 	 * problem and need fixing.
1505 	 */
1506 	space = sbspace(&so->so_snd);
1507 	if (flags & MSG_OOB)
1508 		space += 1024;
1509 	space -= clen;
1510 	SOCKBUF_UNLOCK(&so->so_snd);
1511 	if (resid > space) {
1512 		error = EMSGSIZE;
1513 		goto out;
1514 	}
1515 	if (uio == NULL) {
1516 		resid = 0;
1517 		if (flags & MSG_EOR)
1518 			top->m_flags |= M_EOR;
1519 	} else {
1520 		/*
1521 		 * Copy the data from userland into a mbuf chain.
1522 		 * If no data is to be copied in, a single empty mbuf
1523 		 * is returned.
1524 		 */
1525 		top = m_uiotombuf(uio, M_WAITOK, space, max_hdr,
1526 		    (M_PKTHDR | ((flags & MSG_EOR) ? M_EOR : 0)));
1527 		if (top == NULL) {
1528 			error = EFAULT;	/* only possible error */
1529 			goto out;
1530 		}
1531 		space -= resid - uio->uio_resid;
1532 		resid = uio->uio_resid;
1533 	}
1534 	KASSERT(resid == 0, ("sosend_dgram: resid != 0"));
1535 	/*
1536 	 * XXXRW: Frobbing SO_DONTROUTE here is even worse without sblock
1537 	 * than with.
1538 	 */
1539 	if (dontroute) {
1540 		SOCK_LOCK(so);
1541 		so->so_options |= SO_DONTROUTE;
1542 		SOCK_UNLOCK(so);
1543 	}
1544 	/*
1545 	 * XXX all the SBS_CANTSENDMORE checks previously done could be out
1546 	 * of date.  We could have received a reset packet in an interrupt or
1547 	 * maybe we slept while doing page faults in uiomove() etc.  We could
1548 	 * probably recheck again inside the locking protection here, but
1549 	 * there are probably other places that this also happens.  We must
1550 	 * rethink this.
1551 	 */
1552 	VNET_SO_ASSERT(so);
1553 	error = so->so_proto->pr_send(so, (flags & MSG_OOB) ? PRUS_OOB :
1554 	/*
1555 	 * If the user set MSG_EOF, the protocol understands this flag and
1556 	 * nothing left to send then use PRU_SEND_EOF instead of PRU_SEND.
1557 	 */
1558 	    ((flags & MSG_EOF) &&
1559 	     (so->so_proto->pr_flags & PR_IMPLOPCL) &&
1560 	     (resid <= 0)) ?
1561 		PRUS_EOF :
1562 		/* If there is more to send set PRUS_MORETOCOME */
1563 		(flags & MSG_MORETOCOME) ||
1564 		(resid > 0 && space > 0) ? PRUS_MORETOCOME : 0,
1565 		top, addr, control, td);
1566 	if (dontroute) {
1567 		SOCK_LOCK(so);
1568 		so->so_options &= ~SO_DONTROUTE;
1569 		SOCK_UNLOCK(so);
1570 	}
1571 	clen = 0;
1572 	control = NULL;
1573 	top = NULL;
1574 out:
1575 	if (top != NULL)
1576 		m_freem(top);
1577 	if (control != NULL)
1578 		m_freem(control);
1579 	return (error);
1580 }
1581 
1582 /*
1583  * Send on a socket.  If send must go all at once and message is larger than
1584  * send buffering, then hard error.  Lock against other senders.  If must go
1585  * all at once and not enough room now, then inform user that this would
1586  * block and do nothing.  Otherwise, if nonblocking, send as much as
1587  * possible.  The data to be sent is described by "uio" if nonzero, otherwise
1588  * by the mbuf chain "top" (which must be null if uio is not).  Data provided
1589  * in mbuf chain must be small enough to send all at once.
1590  *
1591  * Returns nonzero on error, timeout or signal; callers must check for short
1592  * counts if EINTR/ERESTART are returned.  Data and control buffers are freed
1593  * on return.
1594  */
1595 int
1596 sosend_generic(struct socket *so, struct sockaddr *addr, struct uio *uio,
1597     struct mbuf *top, struct mbuf *control, int flags, struct thread *td)
1598 {
1599 	long space;
1600 	ssize_t resid;
1601 	int clen = 0, error, dontroute;
1602 	int atomic = sosendallatonce(so) || top;
1603 	int pr_send_flag;
1604 #ifdef KERN_TLS
1605 	struct ktls_session *tls;
1606 	int tls_enq_cnt, tls_send_flag;
1607 	uint8_t tls_rtype;
1608 
1609 	tls = NULL;
1610 	tls_rtype = TLS_RLTYPE_APP;
1611 #endif
1612 	if (uio != NULL)
1613 		resid = uio->uio_resid;
1614 	else if ((top->m_flags & M_PKTHDR) != 0)
1615 		resid = top->m_pkthdr.len;
1616 	else
1617 		resid = m_length(top, NULL);
1618 	/*
1619 	 * In theory resid should be unsigned.  However, space must be
1620 	 * signed, as it might be less than 0 if we over-committed, and we
1621 	 * must use a signed comparison of space and resid.  On the other
1622 	 * hand, a negative resid causes us to loop sending 0-length
1623 	 * segments to the protocol.
1624 	 *
1625 	 * Also check to make sure that MSG_EOR isn't used on SOCK_STREAM
1626 	 * type sockets since that's an error.
1627 	 */
1628 	if (resid < 0 || (so->so_type == SOCK_STREAM && (flags & MSG_EOR))) {
1629 		error = EINVAL;
1630 		goto out;
1631 	}
1632 
1633 	dontroute =
1634 	    (flags & MSG_DONTROUTE) && (so->so_options & SO_DONTROUTE) == 0 &&
1635 	    (so->so_proto->pr_flags & PR_ATOMIC);
1636 	if (td != NULL)
1637 		td->td_ru.ru_msgsnd++;
1638 	if (control != NULL)
1639 		clen = control->m_len;
1640 
1641 	error = SOCK_IO_SEND_LOCK(so, SBLOCKWAIT(flags));
1642 	if (error)
1643 		goto out;
1644 
1645 #ifdef KERN_TLS
1646 	tls_send_flag = 0;
1647 	tls = ktls_hold(so->so_snd.sb_tls_info);
1648 	if (tls != NULL) {
1649 		if (tls->mode == TCP_TLS_MODE_SW)
1650 			tls_send_flag = PRUS_NOTREADY;
1651 
1652 		if (control != NULL) {
1653 			struct cmsghdr *cm = mtod(control, struct cmsghdr *);
1654 
1655 			if (clen >= sizeof(*cm) &&
1656 			    cm->cmsg_type == TLS_SET_RECORD_TYPE) {
1657 				tls_rtype = *((uint8_t *)CMSG_DATA(cm));
1658 				clen = 0;
1659 				m_freem(control);
1660 				control = NULL;
1661 				atomic = 1;
1662 			}
1663 		}
1664 
1665 		if (resid == 0 && !ktls_permit_empty_frames(tls)) {
1666 			error = EINVAL;
1667 			goto release;
1668 		}
1669 	}
1670 #endif
1671 
1672 restart:
1673 	do {
1674 		SOCKBUF_LOCK(&so->so_snd);
1675 		if (so->so_snd.sb_state & SBS_CANTSENDMORE) {
1676 			SOCKBUF_UNLOCK(&so->so_snd);
1677 			error = EPIPE;
1678 			goto release;
1679 		}
1680 		if (so->so_error) {
1681 			error = so->so_error;
1682 			so->so_error = 0;
1683 			SOCKBUF_UNLOCK(&so->so_snd);
1684 			goto release;
1685 		}
1686 		if ((so->so_state & SS_ISCONNECTED) == 0) {
1687 			/*
1688 			 * `sendto' and `sendmsg' is allowed on a connection-
1689 			 * based socket if it supports implied connect.
1690 			 * Return ENOTCONN if not connected and no address is
1691 			 * supplied.
1692 			 */
1693 			if ((so->so_proto->pr_flags & PR_CONNREQUIRED) &&
1694 			    (so->so_proto->pr_flags & PR_IMPLOPCL) == 0) {
1695 				if ((so->so_state & SS_ISCONFIRMING) == 0 &&
1696 				    !(resid == 0 && clen != 0)) {
1697 					SOCKBUF_UNLOCK(&so->so_snd);
1698 					error = ENOTCONN;
1699 					goto release;
1700 				}
1701 			} else if (addr == NULL) {
1702 				SOCKBUF_UNLOCK(&so->so_snd);
1703 				if (so->so_proto->pr_flags & PR_CONNREQUIRED)
1704 					error = ENOTCONN;
1705 				else
1706 					error = EDESTADDRREQ;
1707 				goto release;
1708 			}
1709 		}
1710 		space = sbspace(&so->so_snd);
1711 		if (flags & MSG_OOB)
1712 			space += 1024;
1713 		if ((atomic && resid > so->so_snd.sb_hiwat) ||
1714 		    clen > so->so_snd.sb_hiwat) {
1715 			SOCKBUF_UNLOCK(&so->so_snd);
1716 			error = EMSGSIZE;
1717 			goto release;
1718 		}
1719 		if (space < resid + clen &&
1720 		    (atomic || space < so->so_snd.sb_lowat || space < clen)) {
1721 			if ((so->so_state & SS_NBIO) ||
1722 			    (flags & (MSG_NBIO | MSG_DONTWAIT)) != 0) {
1723 				SOCKBUF_UNLOCK(&so->so_snd);
1724 				error = EWOULDBLOCK;
1725 				goto release;
1726 			}
1727 			error = sbwait(so, SO_SND);
1728 			SOCKBUF_UNLOCK(&so->so_snd);
1729 			if (error)
1730 				goto release;
1731 			goto restart;
1732 		}
1733 		SOCKBUF_UNLOCK(&so->so_snd);
1734 		space -= clen;
1735 		do {
1736 			if (uio == NULL) {
1737 				resid = 0;
1738 				if (flags & MSG_EOR)
1739 					top->m_flags |= M_EOR;
1740 #ifdef KERN_TLS
1741 				if (tls != NULL) {
1742 					ktls_frame(top, tls, &tls_enq_cnt,
1743 					    tls_rtype);
1744 					tls_rtype = TLS_RLTYPE_APP;
1745 				}
1746 #endif
1747 			} else {
1748 				/*
1749 				 * Copy the data from userland into a mbuf
1750 				 * chain.  If resid is 0, which can happen
1751 				 * only if we have control to send, then
1752 				 * a single empty mbuf is returned.  This
1753 				 * is a workaround to prevent protocol send
1754 				 * methods to panic.
1755 				 */
1756 #ifdef KERN_TLS
1757 				if (tls != NULL) {
1758 					top = m_uiotombuf(uio, M_WAITOK, space,
1759 					    tls->params.max_frame_len,
1760 					    M_EXTPG |
1761 					    ((flags & MSG_EOR) ? M_EOR : 0));
1762 					if (top != NULL) {
1763 						ktls_frame(top, tls,
1764 						    &tls_enq_cnt, tls_rtype);
1765 					}
1766 					tls_rtype = TLS_RLTYPE_APP;
1767 				} else
1768 #endif
1769 					top = m_uiotombuf(uio, M_WAITOK, space,
1770 					    (atomic ? max_hdr : 0),
1771 					    (atomic ? M_PKTHDR : 0) |
1772 					    ((flags & MSG_EOR) ? M_EOR : 0));
1773 				if (top == NULL) {
1774 					error = EFAULT; /* only possible error */
1775 					goto release;
1776 				}
1777 				space -= resid - uio->uio_resid;
1778 				resid = uio->uio_resid;
1779 			}
1780 			if (dontroute) {
1781 				SOCK_LOCK(so);
1782 				so->so_options |= SO_DONTROUTE;
1783 				SOCK_UNLOCK(so);
1784 			}
1785 			/*
1786 			 * XXX all the SBS_CANTSENDMORE checks previously
1787 			 * done could be out of date.  We could have received
1788 			 * a reset packet in an interrupt or maybe we slept
1789 			 * while doing page faults in uiomove() etc.  We
1790 			 * could probably recheck again inside the locking
1791 			 * protection here, but there are probably other
1792 			 * places that this also happens.  We must rethink
1793 			 * this.
1794 			 */
1795 			VNET_SO_ASSERT(so);
1796 
1797 			pr_send_flag = (flags & MSG_OOB) ? PRUS_OOB :
1798 			/*
1799 			 * If the user set MSG_EOF, the protocol understands
1800 			 * this flag and nothing left to send then use
1801 			 * PRU_SEND_EOF instead of PRU_SEND.
1802 			 */
1803 			    ((flags & MSG_EOF) &&
1804 			     (so->so_proto->pr_flags & PR_IMPLOPCL) &&
1805 			     (resid <= 0)) ?
1806 				PRUS_EOF :
1807 			/* If there is more to send set PRUS_MORETOCOME. */
1808 			    (flags & MSG_MORETOCOME) ||
1809 			    (resid > 0 && space > 0) ? PRUS_MORETOCOME : 0;
1810 
1811 #ifdef KERN_TLS
1812 			pr_send_flag |= tls_send_flag;
1813 #endif
1814 
1815 			error = so->so_proto->pr_send(so, pr_send_flag, top,
1816 			    addr, control, td);
1817 
1818 			if (dontroute) {
1819 				SOCK_LOCK(so);
1820 				so->so_options &= ~SO_DONTROUTE;
1821 				SOCK_UNLOCK(so);
1822 			}
1823 
1824 #ifdef KERN_TLS
1825 			if (tls != NULL && tls->mode == TCP_TLS_MODE_SW) {
1826 				if (error != 0) {
1827 					m_freem(top);
1828 					top = NULL;
1829 				} else {
1830 					soref(so);
1831 					ktls_enqueue(top, so, tls_enq_cnt);
1832 				}
1833 			}
1834 #endif
1835 			clen = 0;
1836 			control = NULL;
1837 			top = NULL;
1838 			if (error)
1839 				goto release;
1840 		} while (resid && space > 0);
1841 	} while (resid);
1842 
1843 release:
1844 	SOCK_IO_SEND_UNLOCK(so);
1845 out:
1846 #ifdef KERN_TLS
1847 	if (tls != NULL)
1848 		ktls_free(tls);
1849 #endif
1850 	if (top != NULL)
1851 		m_freem(top);
1852 	if (control != NULL)
1853 		m_freem(control);
1854 	return (error);
1855 }
1856 
1857 /*
1858  * Send to a socket from a kernel thread.
1859  *
1860  * XXXGL: in almost all cases uio is NULL and the mbuf is supplied.
1861  * Exception is nfs/bootp_subr.c.  It is arguable that the VNET context needs
1862  * to be set at all.  This function should just boil down to a static inline
1863  * calling the protocol method.
1864  */
1865 int
1866 sosend(struct socket *so, struct sockaddr *addr, struct uio *uio,
1867     struct mbuf *top, struct mbuf *control, int flags, struct thread *td)
1868 {
1869 	int error;
1870 
1871 	CURVNET_SET(so->so_vnet);
1872 	error = so->so_proto->pr_sosend(so, addr, uio,
1873 	    top, control, flags, td);
1874 	CURVNET_RESTORE();
1875 	return (error);
1876 }
1877 
1878 /*
1879  * send(2), write(2) or aio_write(2) on a socket.
1880  */
1881 int
1882 sousrsend(struct socket *so, struct sockaddr *addr, struct uio *uio,
1883     struct mbuf *control, int flags, struct proc *userproc)
1884 {
1885 	struct thread *td;
1886 	ssize_t len;
1887 	int error;
1888 
1889 	td = uio->uio_td;
1890 	len = uio->uio_resid;
1891 	CURVNET_SET(so->so_vnet);
1892 	error = so->so_proto->pr_sosend(so, addr, uio, NULL, control, flags,
1893 	    td);
1894 	CURVNET_RESTORE();
1895 	if (error != 0) {
1896 		/*
1897 		 * Clear transient errors for stream protocols if they made
1898 		 * some progress.  Make exclusion for aio(4) that would
1899 		 * schedule a new write in case of EWOULDBLOCK and clear
1900 		 * error itself.  See soaio_process_job().
1901 		 */
1902 		if (uio->uio_resid != len &&
1903 		    (so->so_proto->pr_flags & PR_ATOMIC) == 0 &&
1904 		    userproc == NULL &&
1905 		    (error == ERESTART || error == EINTR ||
1906 		    error == EWOULDBLOCK))
1907 			error = 0;
1908 		/* Generation of SIGPIPE can be controlled per socket. */
1909 		if (error == EPIPE && (so->so_options & SO_NOSIGPIPE) == 0 &&
1910 		    (flags & MSG_NOSIGNAL) == 0) {
1911 			if (userproc != NULL) {
1912 				/* aio(4) job */
1913 				PROC_LOCK(userproc);
1914 				kern_psignal(userproc, SIGPIPE);
1915 				PROC_UNLOCK(userproc);
1916 			} else {
1917 				PROC_LOCK(td->td_proc);
1918 				tdsignal(td, SIGPIPE);
1919 				PROC_UNLOCK(td->td_proc);
1920 			}
1921 		}
1922 	}
1923 	return (error);
1924 }
1925 
1926 /*
1927  * The part of soreceive() that implements reading non-inline out-of-band
1928  * data from a socket.  For more complete comments, see soreceive(), from
1929  * which this code originated.
1930  *
1931  * Note that soreceive_rcvoob(), unlike the remainder of soreceive(), is
1932  * unable to return an mbuf chain to the caller.
1933  */
1934 static int
1935 soreceive_rcvoob(struct socket *so, struct uio *uio, int flags)
1936 {
1937 	struct protosw *pr = so->so_proto;
1938 	struct mbuf *m;
1939 	int error;
1940 
1941 	KASSERT(flags & MSG_OOB, ("soreceive_rcvoob: (flags & MSG_OOB) == 0"));
1942 	VNET_SO_ASSERT(so);
1943 
1944 	m = m_get(M_WAITOK, MT_DATA);
1945 	error = pr->pr_rcvoob(so, m, flags & MSG_PEEK);
1946 	if (error)
1947 		goto bad;
1948 	do {
1949 		error = uiomove(mtod(m, void *),
1950 		    (int) min(uio->uio_resid, m->m_len), uio);
1951 		m = m_free(m);
1952 	} while (uio->uio_resid && error == 0 && m);
1953 bad:
1954 	if (m != NULL)
1955 		m_freem(m);
1956 	return (error);
1957 }
1958 
1959 /*
1960  * Following replacement or removal of the first mbuf on the first mbuf chain
1961  * of a socket buffer, push necessary state changes back into the socket
1962  * buffer so that other consumers see the values consistently.  'nextrecord'
1963  * is the callers locally stored value of the original value of
1964  * sb->sb_mb->m_nextpkt which must be restored when the lead mbuf changes.
1965  * NOTE: 'nextrecord' may be NULL.
1966  */
1967 static __inline void
1968 sockbuf_pushsync(struct sockbuf *sb, struct mbuf *nextrecord)
1969 {
1970 
1971 	SOCKBUF_LOCK_ASSERT(sb);
1972 	/*
1973 	 * First, update for the new value of nextrecord.  If necessary, make
1974 	 * it the first record.
1975 	 */
1976 	if (sb->sb_mb != NULL)
1977 		sb->sb_mb->m_nextpkt = nextrecord;
1978 	else
1979 		sb->sb_mb = nextrecord;
1980 
1981 	/*
1982 	 * Now update any dependent socket buffer fields to reflect the new
1983 	 * state.  This is an expanded inline of SB_EMPTY_FIXUP(), with the
1984 	 * addition of a second clause that takes care of the case where
1985 	 * sb_mb has been updated, but remains the last record.
1986 	 */
1987 	if (sb->sb_mb == NULL) {
1988 		sb->sb_mbtail = NULL;
1989 		sb->sb_lastrecord = NULL;
1990 	} else if (sb->sb_mb->m_nextpkt == NULL)
1991 		sb->sb_lastrecord = sb->sb_mb;
1992 }
1993 
1994 /*
1995  * Implement receive operations on a socket.  We depend on the way that
1996  * records are added to the sockbuf by sbappend.  In particular, each record
1997  * (mbufs linked through m_next) must begin with an address if the protocol
1998  * so specifies, followed by an optional mbuf or mbufs containing ancillary
1999  * data, and then zero or more mbufs of data.  In order to allow parallelism
2000  * between network receive and copying to user space, as well as avoid
2001  * sleeping with a mutex held, we release the socket buffer mutex during the
2002  * user space copy.  Although the sockbuf is locked, new data may still be
2003  * appended, and thus we must maintain consistency of the sockbuf during that
2004  * time.
2005  *
2006  * The caller may receive the data as a single mbuf chain by supplying an
2007  * mbuf **mp0 for use in returning the chain.  The uio is then used only for
2008  * the count in uio_resid.
2009  */
2010 int
2011 soreceive_generic(struct socket *so, struct sockaddr **psa, struct uio *uio,
2012     struct mbuf **mp0, struct mbuf **controlp, int *flagsp)
2013 {
2014 	struct mbuf *m, **mp;
2015 	int flags, error, offset;
2016 	ssize_t len;
2017 	struct protosw *pr = so->so_proto;
2018 	struct mbuf *nextrecord;
2019 	int moff, type = 0;
2020 	ssize_t orig_resid = uio->uio_resid;
2021 	bool report_real_len = false;
2022 
2023 	mp = mp0;
2024 	if (psa != NULL)
2025 		*psa = NULL;
2026 	if (controlp != NULL)
2027 		*controlp = NULL;
2028 	if (flagsp != NULL) {
2029 		report_real_len = *flagsp & MSG_TRUNC;
2030 		*flagsp &= ~MSG_TRUNC;
2031 		flags = *flagsp &~ MSG_EOR;
2032 	} else
2033 		flags = 0;
2034 	if (flags & MSG_OOB)
2035 		return (soreceive_rcvoob(so, uio, flags));
2036 	if (mp != NULL)
2037 		*mp = NULL;
2038 	if ((pr->pr_flags & PR_WANTRCVD) && (so->so_state & SS_ISCONFIRMING)
2039 	    && uio->uio_resid) {
2040 		VNET_SO_ASSERT(so);
2041 		pr->pr_rcvd(so, 0);
2042 	}
2043 
2044 	error = SOCK_IO_RECV_LOCK(so, SBLOCKWAIT(flags));
2045 	if (error)
2046 		return (error);
2047 
2048 restart:
2049 	SOCKBUF_LOCK(&so->so_rcv);
2050 	m = so->so_rcv.sb_mb;
2051 	/*
2052 	 * If we have less data than requested, block awaiting more (subject
2053 	 * to any timeout) if:
2054 	 *   1. the current count is less than the low water mark, or
2055 	 *   2. MSG_DONTWAIT is not set
2056 	 */
2057 	if (m == NULL || (((flags & MSG_DONTWAIT) == 0 &&
2058 	    sbavail(&so->so_rcv) < uio->uio_resid) &&
2059 	    sbavail(&so->so_rcv) < so->so_rcv.sb_lowat &&
2060 	    m->m_nextpkt == NULL && (pr->pr_flags & PR_ATOMIC) == 0)) {
2061 		KASSERT(m != NULL || !sbavail(&so->so_rcv),
2062 		    ("receive: m == %p sbavail == %u",
2063 		    m, sbavail(&so->so_rcv)));
2064 		if (so->so_error || so->so_rerror) {
2065 			if (m != NULL)
2066 				goto dontblock;
2067 			if (so->so_error)
2068 				error = so->so_error;
2069 			else
2070 				error = so->so_rerror;
2071 			if ((flags & MSG_PEEK) == 0) {
2072 				if (so->so_error)
2073 					so->so_error = 0;
2074 				else
2075 					so->so_rerror = 0;
2076 			}
2077 			SOCKBUF_UNLOCK(&so->so_rcv);
2078 			goto release;
2079 		}
2080 		SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2081 		if (so->so_rcv.sb_state & SBS_CANTRCVMORE) {
2082 			if (m != NULL)
2083 				goto dontblock;
2084 #ifdef KERN_TLS
2085 			else if (so->so_rcv.sb_tlsdcc == 0 &&
2086 			    so->so_rcv.sb_tlscc == 0) {
2087 #else
2088 			else {
2089 #endif
2090 				SOCKBUF_UNLOCK(&so->so_rcv);
2091 				goto release;
2092 			}
2093 		}
2094 		for (; m != NULL; m = m->m_next)
2095 			if (m->m_type == MT_OOBDATA  || (m->m_flags & M_EOR)) {
2096 				m = so->so_rcv.sb_mb;
2097 				goto dontblock;
2098 			}
2099 		if ((so->so_state & (SS_ISCONNECTING | SS_ISCONNECTED |
2100 		    SS_ISDISCONNECTING | SS_ISDISCONNECTED)) == 0 &&
2101 		    (so->so_proto->pr_flags & PR_CONNREQUIRED) != 0) {
2102 			SOCKBUF_UNLOCK(&so->so_rcv);
2103 			error = ENOTCONN;
2104 			goto release;
2105 		}
2106 		if (uio->uio_resid == 0 && !report_real_len) {
2107 			SOCKBUF_UNLOCK(&so->so_rcv);
2108 			goto release;
2109 		}
2110 		if ((so->so_state & SS_NBIO) ||
2111 		    (flags & (MSG_DONTWAIT|MSG_NBIO))) {
2112 			SOCKBUF_UNLOCK(&so->so_rcv);
2113 			error = EWOULDBLOCK;
2114 			goto release;
2115 		}
2116 		SBLASTRECORDCHK(&so->so_rcv);
2117 		SBLASTMBUFCHK(&so->so_rcv);
2118 		error = sbwait(so, SO_RCV);
2119 		SOCKBUF_UNLOCK(&so->so_rcv);
2120 		if (error)
2121 			goto release;
2122 		goto restart;
2123 	}
2124 dontblock:
2125 	/*
2126 	 * From this point onward, we maintain 'nextrecord' as a cache of the
2127 	 * pointer to the next record in the socket buffer.  We must keep the
2128 	 * various socket buffer pointers and local stack versions of the
2129 	 * pointers in sync, pushing out modifications before dropping the
2130 	 * socket buffer mutex, and re-reading them when picking it up.
2131 	 *
2132 	 * Otherwise, we will race with the network stack appending new data
2133 	 * or records onto the socket buffer by using inconsistent/stale
2134 	 * versions of the field, possibly resulting in socket buffer
2135 	 * corruption.
2136 	 *
2137 	 * By holding the high-level sblock(), we prevent simultaneous
2138 	 * readers from pulling off the front of the socket buffer.
2139 	 */
2140 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2141 	if (uio->uio_td)
2142 		uio->uio_td->td_ru.ru_msgrcv++;
2143 	KASSERT(m == so->so_rcv.sb_mb, ("soreceive: m != so->so_rcv.sb_mb"));
2144 	SBLASTRECORDCHK(&so->so_rcv);
2145 	SBLASTMBUFCHK(&so->so_rcv);
2146 	nextrecord = m->m_nextpkt;
2147 	if (pr->pr_flags & PR_ADDR) {
2148 		KASSERT(m->m_type == MT_SONAME,
2149 		    ("m->m_type == %d", m->m_type));
2150 		orig_resid = 0;
2151 		if (psa != NULL)
2152 			*psa = sodupsockaddr(mtod(m, struct sockaddr *),
2153 			    M_NOWAIT);
2154 		if (flags & MSG_PEEK) {
2155 			m = m->m_next;
2156 		} else {
2157 			sbfree(&so->so_rcv, m);
2158 			so->so_rcv.sb_mb = m_free(m);
2159 			m = so->so_rcv.sb_mb;
2160 			sockbuf_pushsync(&so->so_rcv, nextrecord);
2161 		}
2162 	}
2163 
2164 	/*
2165 	 * Process one or more MT_CONTROL mbufs present before any data mbufs
2166 	 * in the first mbuf chain on the socket buffer.  If MSG_PEEK, we
2167 	 * just copy the data; if !MSG_PEEK, we call into the protocol to
2168 	 * perform externalization (or freeing if controlp == NULL).
2169 	 */
2170 	if (m != NULL && m->m_type == MT_CONTROL) {
2171 		struct mbuf *cm = NULL, *cmn;
2172 		struct mbuf **cme = &cm;
2173 #ifdef KERN_TLS
2174 		struct cmsghdr *cmsg;
2175 		struct tls_get_record tgr;
2176 
2177 		/*
2178 		 * For MSG_TLSAPPDATA, check for an alert record.
2179 		 * If found, return ENXIO without removing
2180 		 * it from the receive queue.  This allows a subsequent
2181 		 * call without MSG_TLSAPPDATA to receive it.
2182 		 * Note that, for TLS, there should only be a single
2183 		 * control mbuf with the TLS_GET_RECORD message in it.
2184 		 */
2185 		if (flags & MSG_TLSAPPDATA) {
2186 			cmsg = mtod(m, struct cmsghdr *);
2187 			if (cmsg->cmsg_type == TLS_GET_RECORD &&
2188 			    cmsg->cmsg_len == CMSG_LEN(sizeof(tgr))) {
2189 				memcpy(&tgr, CMSG_DATA(cmsg), sizeof(tgr));
2190 				if (__predict_false(tgr.tls_type ==
2191 				    TLS_RLTYPE_ALERT)) {
2192 					SOCKBUF_UNLOCK(&so->so_rcv);
2193 					error = ENXIO;
2194 					goto release;
2195 				}
2196 			}
2197 		}
2198 #endif
2199 
2200 		do {
2201 			if (flags & MSG_PEEK) {
2202 				if (controlp != NULL) {
2203 					*controlp = m_copym(m, 0, m->m_len,
2204 					    M_NOWAIT);
2205 					controlp = &(*controlp)->m_next;
2206 				}
2207 				m = m->m_next;
2208 			} else {
2209 				sbfree(&so->so_rcv, m);
2210 				so->so_rcv.sb_mb = m->m_next;
2211 				m->m_next = NULL;
2212 				*cme = m;
2213 				cme = &(*cme)->m_next;
2214 				m = so->so_rcv.sb_mb;
2215 			}
2216 		} while (m != NULL && m->m_type == MT_CONTROL);
2217 		if ((flags & MSG_PEEK) == 0)
2218 			sockbuf_pushsync(&so->so_rcv, nextrecord);
2219 		while (cm != NULL) {
2220 			cmn = cm->m_next;
2221 			cm->m_next = NULL;
2222 			if (pr->pr_domain->dom_externalize != NULL) {
2223 				SOCKBUF_UNLOCK(&so->so_rcv);
2224 				VNET_SO_ASSERT(so);
2225 				error = (*pr->pr_domain->dom_externalize)
2226 				    (cm, controlp, flags);
2227 				SOCKBUF_LOCK(&so->so_rcv);
2228 			} else if (controlp != NULL)
2229 				*controlp = cm;
2230 			else
2231 				m_freem(cm);
2232 			if (controlp != NULL) {
2233 				while (*controlp != NULL)
2234 					controlp = &(*controlp)->m_next;
2235 			}
2236 			cm = cmn;
2237 		}
2238 		if (m != NULL)
2239 			nextrecord = so->so_rcv.sb_mb->m_nextpkt;
2240 		else
2241 			nextrecord = so->so_rcv.sb_mb;
2242 		orig_resid = 0;
2243 	}
2244 	if (m != NULL) {
2245 		if ((flags & MSG_PEEK) == 0) {
2246 			KASSERT(m->m_nextpkt == nextrecord,
2247 			    ("soreceive: post-control, nextrecord !sync"));
2248 			if (nextrecord == NULL) {
2249 				KASSERT(so->so_rcv.sb_mb == m,
2250 				    ("soreceive: post-control, sb_mb!=m"));
2251 				KASSERT(so->so_rcv.sb_lastrecord == m,
2252 				    ("soreceive: post-control, lastrecord!=m"));
2253 			}
2254 		}
2255 		type = m->m_type;
2256 		if (type == MT_OOBDATA)
2257 			flags |= MSG_OOB;
2258 	} else {
2259 		if ((flags & MSG_PEEK) == 0) {
2260 			KASSERT(so->so_rcv.sb_mb == nextrecord,
2261 			    ("soreceive: sb_mb != nextrecord"));
2262 			if (so->so_rcv.sb_mb == NULL) {
2263 				KASSERT(so->so_rcv.sb_lastrecord == NULL,
2264 				    ("soreceive: sb_lastercord != NULL"));
2265 			}
2266 		}
2267 	}
2268 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2269 	SBLASTRECORDCHK(&so->so_rcv);
2270 	SBLASTMBUFCHK(&so->so_rcv);
2271 
2272 	/*
2273 	 * Now continue to read any data mbufs off of the head of the socket
2274 	 * buffer until the read request is satisfied.  Note that 'type' is
2275 	 * used to store the type of any mbuf reads that have happened so far
2276 	 * such that soreceive() can stop reading if the type changes, which
2277 	 * causes soreceive() to return only one of regular data and inline
2278 	 * out-of-band data in a single socket receive operation.
2279 	 */
2280 	moff = 0;
2281 	offset = 0;
2282 	while (m != NULL && !(m->m_flags & M_NOTAVAIL) && uio->uio_resid > 0
2283 	    && error == 0) {
2284 		/*
2285 		 * If the type of mbuf has changed since the last mbuf
2286 		 * examined ('type'), end the receive operation.
2287 		 */
2288 		SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2289 		if (m->m_type == MT_OOBDATA || m->m_type == MT_CONTROL) {
2290 			if (type != m->m_type)
2291 				break;
2292 		} else if (type == MT_OOBDATA)
2293 			break;
2294 		else
2295 		    KASSERT(m->m_type == MT_DATA,
2296 			("m->m_type == %d", m->m_type));
2297 		so->so_rcv.sb_state &= ~SBS_RCVATMARK;
2298 		len = uio->uio_resid;
2299 		if (so->so_oobmark && len > so->so_oobmark - offset)
2300 			len = so->so_oobmark - offset;
2301 		if (len > m->m_len - moff)
2302 			len = m->m_len - moff;
2303 		/*
2304 		 * If mp is set, just pass back the mbufs.  Otherwise copy
2305 		 * them out via the uio, then free.  Sockbuf must be
2306 		 * consistent here (points to current mbuf, it points to next
2307 		 * record) when we drop priority; we must note any additions
2308 		 * to the sockbuf when we block interrupts again.
2309 		 */
2310 		if (mp == NULL) {
2311 			SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2312 			SBLASTRECORDCHK(&so->so_rcv);
2313 			SBLASTMBUFCHK(&so->so_rcv);
2314 			SOCKBUF_UNLOCK(&so->so_rcv);
2315 			if ((m->m_flags & M_EXTPG) != 0)
2316 				error = m_unmapped_uiomove(m, moff, uio,
2317 				    (int)len);
2318 			else
2319 				error = uiomove(mtod(m, char *) + moff,
2320 				    (int)len, uio);
2321 			SOCKBUF_LOCK(&so->so_rcv);
2322 			if (error) {
2323 				/*
2324 				 * The MT_SONAME mbuf has already been removed
2325 				 * from the record, so it is necessary to
2326 				 * remove the data mbufs, if any, to preserve
2327 				 * the invariant in the case of PR_ADDR that
2328 				 * requires MT_SONAME mbufs at the head of
2329 				 * each record.
2330 				 */
2331 				if (pr->pr_flags & PR_ATOMIC &&
2332 				    ((flags & MSG_PEEK) == 0))
2333 					(void)sbdroprecord_locked(&so->so_rcv);
2334 				SOCKBUF_UNLOCK(&so->so_rcv);
2335 				goto release;
2336 			}
2337 		} else
2338 			uio->uio_resid -= len;
2339 		SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2340 		if (len == m->m_len - moff) {
2341 			if (m->m_flags & M_EOR)
2342 				flags |= MSG_EOR;
2343 			if (flags & MSG_PEEK) {
2344 				m = m->m_next;
2345 				moff = 0;
2346 			} else {
2347 				nextrecord = m->m_nextpkt;
2348 				sbfree(&so->so_rcv, m);
2349 				if (mp != NULL) {
2350 					m->m_nextpkt = NULL;
2351 					*mp = m;
2352 					mp = &m->m_next;
2353 					so->so_rcv.sb_mb = m = m->m_next;
2354 					*mp = NULL;
2355 				} else {
2356 					so->so_rcv.sb_mb = m_free(m);
2357 					m = so->so_rcv.sb_mb;
2358 				}
2359 				sockbuf_pushsync(&so->so_rcv, nextrecord);
2360 				SBLASTRECORDCHK(&so->so_rcv);
2361 				SBLASTMBUFCHK(&so->so_rcv);
2362 			}
2363 		} else {
2364 			if (flags & MSG_PEEK)
2365 				moff += len;
2366 			else {
2367 				if (mp != NULL) {
2368 					if (flags & MSG_DONTWAIT) {
2369 						*mp = m_copym(m, 0, len,
2370 						    M_NOWAIT);
2371 						if (*mp == NULL) {
2372 							/*
2373 							 * m_copym() couldn't
2374 							 * allocate an mbuf.
2375 							 * Adjust uio_resid back
2376 							 * (it was adjusted
2377 							 * down by len bytes,
2378 							 * which we didn't end
2379 							 * up "copying" over).
2380 							 */
2381 							uio->uio_resid += len;
2382 							break;
2383 						}
2384 					} else {
2385 						SOCKBUF_UNLOCK(&so->so_rcv);
2386 						*mp = m_copym(m, 0, len,
2387 						    M_WAITOK);
2388 						SOCKBUF_LOCK(&so->so_rcv);
2389 					}
2390 				}
2391 				sbcut_locked(&so->so_rcv, len);
2392 			}
2393 		}
2394 		SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2395 		if (so->so_oobmark) {
2396 			if ((flags & MSG_PEEK) == 0) {
2397 				so->so_oobmark -= len;
2398 				if (so->so_oobmark == 0) {
2399 					so->so_rcv.sb_state |= SBS_RCVATMARK;
2400 					break;
2401 				}
2402 			} else {
2403 				offset += len;
2404 				if (offset == so->so_oobmark)
2405 					break;
2406 			}
2407 		}
2408 		if (flags & MSG_EOR)
2409 			break;
2410 		/*
2411 		 * If the MSG_WAITALL flag is set (for non-atomic socket), we
2412 		 * must not quit until "uio->uio_resid == 0" or an error
2413 		 * termination.  If a signal/timeout occurs, return with a
2414 		 * short count but without error.  Keep sockbuf locked
2415 		 * against other readers.
2416 		 */
2417 		while (flags & MSG_WAITALL && m == NULL && uio->uio_resid > 0 &&
2418 		    !sosendallatonce(so) && nextrecord == NULL) {
2419 			SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2420 			if (so->so_error || so->so_rerror ||
2421 			    so->so_rcv.sb_state & SBS_CANTRCVMORE)
2422 				break;
2423 			/*
2424 			 * Notify the protocol that some data has been
2425 			 * drained before blocking.
2426 			 */
2427 			if (pr->pr_flags & PR_WANTRCVD) {
2428 				SOCKBUF_UNLOCK(&so->so_rcv);
2429 				VNET_SO_ASSERT(so);
2430 				pr->pr_rcvd(so, flags);
2431 				SOCKBUF_LOCK(&so->so_rcv);
2432 				if (__predict_false(so->so_rcv.sb_mb == NULL &&
2433 				    (so->so_error || so->so_rerror ||
2434 				    so->so_rcv.sb_state & SBS_CANTRCVMORE)))
2435 					break;
2436 			}
2437 			SBLASTRECORDCHK(&so->so_rcv);
2438 			SBLASTMBUFCHK(&so->so_rcv);
2439 			/*
2440 			 * We could receive some data while was notifying
2441 			 * the protocol. Skip blocking in this case.
2442 			 */
2443 			if (so->so_rcv.sb_mb == NULL) {
2444 				error = sbwait(so, SO_RCV);
2445 				if (error) {
2446 					SOCKBUF_UNLOCK(&so->so_rcv);
2447 					goto release;
2448 				}
2449 			}
2450 			m = so->so_rcv.sb_mb;
2451 			if (m != NULL)
2452 				nextrecord = m->m_nextpkt;
2453 		}
2454 	}
2455 
2456 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2457 	if (m != NULL && pr->pr_flags & PR_ATOMIC) {
2458 		if (report_real_len)
2459 			uio->uio_resid -= m_length(m, NULL) - moff;
2460 		flags |= MSG_TRUNC;
2461 		if ((flags & MSG_PEEK) == 0)
2462 			(void) sbdroprecord_locked(&so->so_rcv);
2463 	}
2464 	if ((flags & MSG_PEEK) == 0) {
2465 		if (m == NULL) {
2466 			/*
2467 			 * First part is an inline SB_EMPTY_FIXUP().  Second
2468 			 * part makes sure sb_lastrecord is up-to-date if
2469 			 * there is still data in the socket buffer.
2470 			 */
2471 			so->so_rcv.sb_mb = nextrecord;
2472 			if (so->so_rcv.sb_mb == NULL) {
2473 				so->so_rcv.sb_mbtail = NULL;
2474 				so->so_rcv.sb_lastrecord = NULL;
2475 			} else if (nextrecord->m_nextpkt == NULL)
2476 				so->so_rcv.sb_lastrecord = nextrecord;
2477 		}
2478 		SBLASTRECORDCHK(&so->so_rcv);
2479 		SBLASTMBUFCHK(&so->so_rcv);
2480 		/*
2481 		 * If soreceive() is being done from the socket callback,
2482 		 * then don't need to generate ACK to peer to update window,
2483 		 * since ACK will be generated on return to TCP.
2484 		 */
2485 		if (!(flags & MSG_SOCALLBCK) &&
2486 		    (pr->pr_flags & PR_WANTRCVD)) {
2487 			SOCKBUF_UNLOCK(&so->so_rcv);
2488 			VNET_SO_ASSERT(so);
2489 			pr->pr_rcvd(so, flags);
2490 			SOCKBUF_LOCK(&so->so_rcv);
2491 		}
2492 	}
2493 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2494 	if (orig_resid == uio->uio_resid && orig_resid &&
2495 	    (flags & MSG_EOR) == 0 && (so->so_rcv.sb_state & SBS_CANTRCVMORE) == 0) {
2496 		SOCKBUF_UNLOCK(&so->so_rcv);
2497 		goto restart;
2498 	}
2499 	SOCKBUF_UNLOCK(&so->so_rcv);
2500 
2501 	if (flagsp != NULL)
2502 		*flagsp |= flags;
2503 release:
2504 	SOCK_IO_RECV_UNLOCK(so);
2505 	return (error);
2506 }
2507 
2508 /*
2509  * Optimized version of soreceive() for stream (TCP) sockets.
2510  */
2511 int
2512 soreceive_stream(struct socket *so, struct sockaddr **psa, struct uio *uio,
2513     struct mbuf **mp0, struct mbuf **controlp, int *flagsp)
2514 {
2515 	int len = 0, error = 0, flags, oresid;
2516 	struct sockbuf *sb;
2517 	struct mbuf *m, *n = NULL;
2518 
2519 	/* We only do stream sockets. */
2520 	if (so->so_type != SOCK_STREAM)
2521 		return (EINVAL);
2522 	if (psa != NULL)
2523 		*psa = NULL;
2524 	if (flagsp != NULL)
2525 		flags = *flagsp &~ MSG_EOR;
2526 	else
2527 		flags = 0;
2528 	if (controlp != NULL)
2529 		*controlp = NULL;
2530 	if (flags & MSG_OOB)
2531 		return (soreceive_rcvoob(so, uio, flags));
2532 	if (mp0 != NULL)
2533 		*mp0 = NULL;
2534 
2535 	sb = &so->so_rcv;
2536 
2537 #ifdef KERN_TLS
2538 	/*
2539 	 * KTLS store TLS records as records with a control message to
2540 	 * describe the framing.
2541 	 *
2542 	 * We check once here before acquiring locks to optimize the
2543 	 * common case.
2544 	 */
2545 	if (sb->sb_tls_info != NULL)
2546 		return (soreceive_generic(so, psa, uio, mp0, controlp,
2547 		    flagsp));
2548 #endif
2549 
2550 	/* Prevent other readers from entering the socket. */
2551 	error = SOCK_IO_RECV_LOCK(so, SBLOCKWAIT(flags));
2552 	if (error)
2553 		return (error);
2554 	SOCKBUF_LOCK(sb);
2555 
2556 #ifdef KERN_TLS
2557 	if (sb->sb_tls_info != NULL) {
2558 		SOCKBUF_UNLOCK(sb);
2559 		SOCK_IO_RECV_UNLOCK(so);
2560 		return (soreceive_generic(so, psa, uio, mp0, controlp,
2561 		    flagsp));
2562 	}
2563 #endif
2564 
2565 	/* Easy one, no space to copyout anything. */
2566 	if (uio->uio_resid == 0) {
2567 		error = EINVAL;
2568 		goto out;
2569 	}
2570 	oresid = uio->uio_resid;
2571 
2572 	/* We will never ever get anything unless we are or were connected. */
2573 	if (!(so->so_state & (SS_ISCONNECTED|SS_ISDISCONNECTED))) {
2574 		error = ENOTCONN;
2575 		goto out;
2576 	}
2577 
2578 restart:
2579 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2580 
2581 	/* Abort if socket has reported problems. */
2582 	if (so->so_error) {
2583 		if (sbavail(sb) > 0)
2584 			goto deliver;
2585 		if (oresid > uio->uio_resid)
2586 			goto out;
2587 		error = so->so_error;
2588 		if (!(flags & MSG_PEEK))
2589 			so->so_error = 0;
2590 		goto out;
2591 	}
2592 
2593 	/* Door is closed.  Deliver what is left, if any. */
2594 	if (sb->sb_state & SBS_CANTRCVMORE) {
2595 		if (sbavail(sb) > 0)
2596 			goto deliver;
2597 		else
2598 			goto out;
2599 	}
2600 
2601 	/* Socket buffer is empty and we shall not block. */
2602 	if (sbavail(sb) == 0 &&
2603 	    ((so->so_state & SS_NBIO) || (flags & (MSG_DONTWAIT|MSG_NBIO)))) {
2604 		error = EAGAIN;
2605 		goto out;
2606 	}
2607 
2608 	/* Socket buffer got some data that we shall deliver now. */
2609 	if (sbavail(sb) > 0 && !(flags & MSG_WAITALL) &&
2610 	    ((so->so_state & SS_NBIO) ||
2611 	     (flags & (MSG_DONTWAIT|MSG_NBIO)) ||
2612 	     sbavail(sb) >= sb->sb_lowat ||
2613 	     sbavail(sb) >= uio->uio_resid ||
2614 	     sbavail(sb) >= sb->sb_hiwat) ) {
2615 		goto deliver;
2616 	}
2617 
2618 	/* On MSG_WAITALL we must wait until all data or error arrives. */
2619 	if ((flags & MSG_WAITALL) &&
2620 	    (sbavail(sb) >= uio->uio_resid || sbavail(sb) >= sb->sb_hiwat))
2621 		goto deliver;
2622 
2623 	/*
2624 	 * Wait and block until (more) data comes in.
2625 	 * NB: Drops the sockbuf lock during wait.
2626 	 */
2627 	error = sbwait(so, SO_RCV);
2628 	if (error)
2629 		goto out;
2630 	goto restart;
2631 
2632 deliver:
2633 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2634 	KASSERT(sbavail(sb) > 0, ("%s: sockbuf empty", __func__));
2635 	KASSERT(sb->sb_mb != NULL, ("%s: sb_mb == NULL", __func__));
2636 
2637 	/* Statistics. */
2638 	if (uio->uio_td)
2639 		uio->uio_td->td_ru.ru_msgrcv++;
2640 
2641 	/* Fill uio until full or current end of socket buffer is reached. */
2642 	len = min(uio->uio_resid, sbavail(sb));
2643 	if (mp0 != NULL) {
2644 		/* Dequeue as many mbufs as possible. */
2645 		if (!(flags & MSG_PEEK) && len >= sb->sb_mb->m_len) {
2646 			if (*mp0 == NULL)
2647 				*mp0 = sb->sb_mb;
2648 			else
2649 				m_cat(*mp0, sb->sb_mb);
2650 			for (m = sb->sb_mb;
2651 			     m != NULL && m->m_len <= len;
2652 			     m = m->m_next) {
2653 				KASSERT(!(m->m_flags & M_NOTAVAIL),
2654 				    ("%s: m %p not available", __func__, m));
2655 				len -= m->m_len;
2656 				uio->uio_resid -= m->m_len;
2657 				sbfree(sb, m);
2658 				n = m;
2659 			}
2660 			n->m_next = NULL;
2661 			sb->sb_mb = m;
2662 			sb->sb_lastrecord = sb->sb_mb;
2663 			if (sb->sb_mb == NULL)
2664 				SB_EMPTY_FIXUP(sb);
2665 		}
2666 		/* Copy the remainder. */
2667 		if (len > 0) {
2668 			KASSERT(sb->sb_mb != NULL,
2669 			    ("%s: len > 0 && sb->sb_mb empty", __func__));
2670 
2671 			m = m_copym(sb->sb_mb, 0, len, M_NOWAIT);
2672 			if (m == NULL)
2673 				len = 0;	/* Don't flush data from sockbuf. */
2674 			else
2675 				uio->uio_resid -= len;
2676 			if (*mp0 != NULL)
2677 				m_cat(*mp0, m);
2678 			else
2679 				*mp0 = m;
2680 			if (*mp0 == NULL) {
2681 				error = ENOBUFS;
2682 				goto out;
2683 			}
2684 		}
2685 	} else {
2686 		/* NB: Must unlock socket buffer as uiomove may sleep. */
2687 		SOCKBUF_UNLOCK(sb);
2688 		error = m_mbuftouio(uio, sb->sb_mb, len);
2689 		SOCKBUF_LOCK(sb);
2690 		if (error)
2691 			goto out;
2692 	}
2693 	SBLASTRECORDCHK(sb);
2694 	SBLASTMBUFCHK(sb);
2695 
2696 	/*
2697 	 * Remove the delivered data from the socket buffer unless we
2698 	 * were only peeking.
2699 	 */
2700 	if (!(flags & MSG_PEEK)) {
2701 		if (len > 0)
2702 			sbdrop_locked(sb, len);
2703 
2704 		/* Notify protocol that we drained some data. */
2705 		if ((so->so_proto->pr_flags & PR_WANTRCVD) &&
2706 		    (((flags & MSG_WAITALL) && uio->uio_resid > 0) ||
2707 		     !(flags & MSG_SOCALLBCK))) {
2708 			SOCKBUF_UNLOCK(sb);
2709 			VNET_SO_ASSERT(so);
2710 			so->so_proto->pr_rcvd(so, flags);
2711 			SOCKBUF_LOCK(sb);
2712 		}
2713 	}
2714 
2715 	/*
2716 	 * For MSG_WAITALL we may have to loop again and wait for
2717 	 * more data to come in.
2718 	 */
2719 	if ((flags & MSG_WAITALL) && uio->uio_resid > 0)
2720 		goto restart;
2721 out:
2722 	SBLASTRECORDCHK(sb);
2723 	SBLASTMBUFCHK(sb);
2724 	SOCKBUF_UNLOCK(sb);
2725 	SOCK_IO_RECV_UNLOCK(so);
2726 	return (error);
2727 }
2728 
2729 /*
2730  * Optimized version of soreceive() for simple datagram cases from userspace.
2731  * Unlike in the stream case, we're able to drop a datagram if copyout()
2732  * fails, and because we handle datagrams atomically, we don't need to use a
2733  * sleep lock to prevent I/O interlacing.
2734  */
2735 int
2736 soreceive_dgram(struct socket *so, struct sockaddr **psa, struct uio *uio,
2737     struct mbuf **mp0, struct mbuf **controlp, int *flagsp)
2738 {
2739 	struct mbuf *m, *m2;
2740 	int flags, error;
2741 	ssize_t len;
2742 	struct protosw *pr = so->so_proto;
2743 	struct mbuf *nextrecord;
2744 
2745 	if (psa != NULL)
2746 		*psa = NULL;
2747 	if (controlp != NULL)
2748 		*controlp = NULL;
2749 	if (flagsp != NULL)
2750 		flags = *flagsp &~ MSG_EOR;
2751 	else
2752 		flags = 0;
2753 
2754 	/*
2755 	 * For any complicated cases, fall back to the full
2756 	 * soreceive_generic().
2757 	 */
2758 	if (mp0 != NULL || (flags & (MSG_PEEK | MSG_OOB | MSG_TRUNC)))
2759 		return (soreceive_generic(so, psa, uio, mp0, controlp,
2760 		    flagsp));
2761 
2762 	/*
2763 	 * Enforce restrictions on use.
2764 	 */
2765 	KASSERT((pr->pr_flags & PR_WANTRCVD) == 0,
2766 	    ("soreceive_dgram: wantrcvd"));
2767 	KASSERT(pr->pr_flags & PR_ATOMIC, ("soreceive_dgram: !atomic"));
2768 	KASSERT((so->so_rcv.sb_state & SBS_RCVATMARK) == 0,
2769 	    ("soreceive_dgram: SBS_RCVATMARK"));
2770 	KASSERT((so->so_proto->pr_flags & PR_CONNREQUIRED) == 0,
2771 	    ("soreceive_dgram: P_CONNREQUIRED"));
2772 
2773 	/*
2774 	 * Loop blocking while waiting for a datagram.
2775 	 */
2776 	SOCKBUF_LOCK(&so->so_rcv);
2777 	while ((m = so->so_rcv.sb_mb) == NULL) {
2778 		KASSERT(sbavail(&so->so_rcv) == 0,
2779 		    ("soreceive_dgram: sb_mb NULL but sbavail %u",
2780 		    sbavail(&so->so_rcv)));
2781 		if (so->so_error) {
2782 			error = so->so_error;
2783 			so->so_error = 0;
2784 			SOCKBUF_UNLOCK(&so->so_rcv);
2785 			return (error);
2786 		}
2787 		if (so->so_rcv.sb_state & SBS_CANTRCVMORE ||
2788 		    uio->uio_resid == 0) {
2789 			SOCKBUF_UNLOCK(&so->so_rcv);
2790 			return (0);
2791 		}
2792 		if ((so->so_state & SS_NBIO) ||
2793 		    (flags & (MSG_DONTWAIT|MSG_NBIO))) {
2794 			SOCKBUF_UNLOCK(&so->so_rcv);
2795 			return (EWOULDBLOCK);
2796 		}
2797 		SBLASTRECORDCHK(&so->so_rcv);
2798 		SBLASTMBUFCHK(&so->so_rcv);
2799 		error = sbwait(so, SO_RCV);
2800 		if (error) {
2801 			SOCKBUF_UNLOCK(&so->so_rcv);
2802 			return (error);
2803 		}
2804 	}
2805 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2806 
2807 	if (uio->uio_td)
2808 		uio->uio_td->td_ru.ru_msgrcv++;
2809 	SBLASTRECORDCHK(&so->so_rcv);
2810 	SBLASTMBUFCHK(&so->so_rcv);
2811 	nextrecord = m->m_nextpkt;
2812 	if (nextrecord == NULL) {
2813 		KASSERT(so->so_rcv.sb_lastrecord == m,
2814 		    ("soreceive_dgram: lastrecord != m"));
2815 	}
2816 
2817 	KASSERT(so->so_rcv.sb_mb->m_nextpkt == nextrecord,
2818 	    ("soreceive_dgram: m_nextpkt != nextrecord"));
2819 
2820 	/*
2821 	 * Pull 'm' and its chain off the front of the packet queue.
2822 	 */
2823 	so->so_rcv.sb_mb = NULL;
2824 	sockbuf_pushsync(&so->so_rcv, nextrecord);
2825 
2826 	/*
2827 	 * Walk 'm's chain and free that many bytes from the socket buffer.
2828 	 */
2829 	for (m2 = m; m2 != NULL; m2 = m2->m_next)
2830 		sbfree(&so->so_rcv, m2);
2831 
2832 	/*
2833 	 * Do a few last checks before we let go of the lock.
2834 	 */
2835 	SBLASTRECORDCHK(&so->so_rcv);
2836 	SBLASTMBUFCHK(&so->so_rcv);
2837 	SOCKBUF_UNLOCK(&so->so_rcv);
2838 
2839 	if (pr->pr_flags & PR_ADDR) {
2840 		KASSERT(m->m_type == MT_SONAME,
2841 		    ("m->m_type == %d", m->m_type));
2842 		if (psa != NULL)
2843 			*psa = sodupsockaddr(mtod(m, struct sockaddr *),
2844 			    M_NOWAIT);
2845 		m = m_free(m);
2846 	}
2847 	if (m == NULL) {
2848 		/* XXXRW: Can this happen? */
2849 		return (0);
2850 	}
2851 
2852 	/*
2853 	 * Packet to copyout() is now in 'm' and it is disconnected from the
2854 	 * queue.
2855 	 *
2856 	 * Process one or more MT_CONTROL mbufs present before any data mbufs
2857 	 * in the first mbuf chain on the socket buffer.  We call into the
2858 	 * protocol to perform externalization (or freeing if controlp ==
2859 	 * NULL). In some cases there can be only MT_CONTROL mbufs without
2860 	 * MT_DATA mbufs.
2861 	 */
2862 	if (m->m_type == MT_CONTROL) {
2863 		struct mbuf *cm = NULL, *cmn;
2864 		struct mbuf **cme = &cm;
2865 
2866 		do {
2867 			m2 = m->m_next;
2868 			m->m_next = NULL;
2869 			*cme = m;
2870 			cme = &(*cme)->m_next;
2871 			m = m2;
2872 		} while (m != NULL && m->m_type == MT_CONTROL);
2873 		while (cm != NULL) {
2874 			cmn = cm->m_next;
2875 			cm->m_next = NULL;
2876 			if (pr->pr_domain->dom_externalize != NULL) {
2877 				error = (*pr->pr_domain->dom_externalize)
2878 				    (cm, controlp, flags);
2879 			} else if (controlp != NULL)
2880 				*controlp = cm;
2881 			else
2882 				m_freem(cm);
2883 			if (controlp != NULL) {
2884 				while (*controlp != NULL)
2885 					controlp = &(*controlp)->m_next;
2886 			}
2887 			cm = cmn;
2888 		}
2889 	}
2890 	KASSERT(m == NULL || m->m_type == MT_DATA,
2891 	    ("soreceive_dgram: !data"));
2892 	while (m != NULL && uio->uio_resid > 0) {
2893 		len = uio->uio_resid;
2894 		if (len > m->m_len)
2895 			len = m->m_len;
2896 		error = uiomove(mtod(m, char *), (int)len, uio);
2897 		if (error) {
2898 			m_freem(m);
2899 			return (error);
2900 		}
2901 		if (len == m->m_len)
2902 			m = m_free(m);
2903 		else {
2904 			m->m_data += len;
2905 			m->m_len -= len;
2906 		}
2907 	}
2908 	if (m != NULL) {
2909 		flags |= MSG_TRUNC;
2910 		m_freem(m);
2911 	}
2912 	if (flagsp != NULL)
2913 		*flagsp |= flags;
2914 	return (0);
2915 }
2916 
2917 int
2918 soreceive(struct socket *so, struct sockaddr **psa, struct uio *uio,
2919     struct mbuf **mp0, struct mbuf **controlp, int *flagsp)
2920 {
2921 	int error;
2922 
2923 	CURVNET_SET(so->so_vnet);
2924 	error = so->so_proto->pr_soreceive(so, psa, uio, mp0, controlp, flagsp);
2925 	CURVNET_RESTORE();
2926 	return (error);
2927 }
2928 
2929 int
2930 soshutdown(struct socket *so, int how)
2931 {
2932 	struct protosw *pr;
2933 	int error, soerror_enotconn;
2934 
2935 	if (!(how == SHUT_RD || how == SHUT_WR || how == SHUT_RDWR))
2936 		return (EINVAL);
2937 
2938 	soerror_enotconn = 0;
2939 	SOCK_LOCK(so);
2940 	if ((so->so_state &
2941 	    (SS_ISCONNECTED | SS_ISCONNECTING | SS_ISDISCONNECTING)) == 0) {
2942 		/*
2943 		 * POSIX mandates us to return ENOTCONN when shutdown(2) is
2944 		 * invoked on a datagram sockets, however historically we would
2945 		 * actually tear socket down. This is known to be leveraged by
2946 		 * some applications to unblock process waiting in recvXXX(2)
2947 		 * by other process that it shares that socket with. Try to meet
2948 		 * both backward-compatibility and POSIX requirements by forcing
2949 		 * ENOTCONN but still asking protocol to perform pru_shutdown().
2950 		 */
2951 		if (so->so_type != SOCK_DGRAM && !SOLISTENING(so)) {
2952 			SOCK_UNLOCK(so);
2953 			return (ENOTCONN);
2954 		}
2955 		soerror_enotconn = 1;
2956 	}
2957 
2958 	if (SOLISTENING(so)) {
2959 		if (how != SHUT_WR) {
2960 			so->so_error = ECONNABORTED;
2961 			solisten_wakeup(so);	/* unlocks so */
2962 		} else {
2963 			SOCK_UNLOCK(so);
2964 		}
2965 		goto done;
2966 	}
2967 	SOCK_UNLOCK(so);
2968 
2969 	CURVNET_SET(so->so_vnet);
2970 	pr = so->so_proto;
2971 	if (pr->pr_flush != NULL)
2972 		pr->pr_flush(so, how);
2973 	if (how != SHUT_WR)
2974 		sorflush(so);
2975 	if (how != SHUT_RD) {
2976 		error = pr->pr_shutdown(so);
2977 		wakeup(&so->so_timeo);
2978 		CURVNET_RESTORE();
2979 		return ((error == 0 && soerror_enotconn) ? ENOTCONN : error);
2980 	}
2981 	wakeup(&so->so_timeo);
2982 	CURVNET_RESTORE();
2983 
2984 done:
2985 	return (soerror_enotconn ? ENOTCONN : 0);
2986 }
2987 
2988 void
2989 sorflush(struct socket *so)
2990 {
2991 	struct protosw *pr;
2992 	int error;
2993 
2994 	VNET_SO_ASSERT(so);
2995 
2996 	/*
2997 	 * Dislodge threads currently blocked in receive and wait to acquire
2998 	 * a lock against other simultaneous readers before clearing the
2999 	 * socket buffer.  Don't let our acquire be interrupted by a signal
3000 	 * despite any existing socket disposition on interruptable waiting.
3001 	 */
3002 	socantrcvmore(so);
3003 
3004 	error = SOCK_IO_RECV_LOCK(so, SBL_WAIT | SBL_NOINTR);
3005 	if (error != 0) {
3006 		KASSERT(SOLISTENING(so),
3007 		    ("%s: soiolock(%p) failed", __func__, so));
3008 		return;
3009 	}
3010 
3011 	pr = so->so_proto;
3012 	if (pr->pr_flags & PR_RIGHTS) {
3013 		MPASS(pr->pr_domain->dom_dispose != NULL);
3014 		(*pr->pr_domain->dom_dispose)(so);
3015 	} else {
3016 		sbrelease(so, SO_RCV);
3017 		SOCK_IO_RECV_UNLOCK(so);
3018 	}
3019 
3020 }
3021 
3022 /*
3023  * Wrapper for Socket established helper hook.
3024  * Parameters: socket, context of the hook point, hook id.
3025  */
3026 static int inline
3027 hhook_run_socket(struct socket *so, void *hctx, int32_t h_id)
3028 {
3029 	struct socket_hhook_data hhook_data = {
3030 		.so = so,
3031 		.hctx = hctx,
3032 		.m = NULL,
3033 		.status = 0
3034 	};
3035 
3036 	CURVNET_SET(so->so_vnet);
3037 	HHOOKS_RUN_IF(V_socket_hhh[h_id], &hhook_data, &so->osd);
3038 	CURVNET_RESTORE();
3039 
3040 	/* Ugly but needed, since hhooks return void for now */
3041 	return (hhook_data.status);
3042 }
3043 
3044 /*
3045  * Perhaps this routine, and sooptcopyout(), below, ought to come in an
3046  * additional variant to handle the case where the option value needs to be
3047  * some kind of integer, but not a specific size.  In addition to their use
3048  * here, these functions are also called by the protocol-level pr_ctloutput()
3049  * routines.
3050  */
3051 int
3052 sooptcopyin(struct sockopt *sopt, void *buf, size_t len, size_t minlen)
3053 {
3054 	size_t	valsize;
3055 
3056 	/*
3057 	 * If the user gives us more than we wanted, we ignore it, but if we
3058 	 * don't get the minimum length the caller wants, we return EINVAL.
3059 	 * On success, sopt->sopt_valsize is set to however much we actually
3060 	 * retrieved.
3061 	 */
3062 	if ((valsize = sopt->sopt_valsize) < minlen)
3063 		return EINVAL;
3064 	if (valsize > len)
3065 		sopt->sopt_valsize = valsize = len;
3066 
3067 	if (sopt->sopt_td != NULL)
3068 		return (copyin(sopt->sopt_val, buf, valsize));
3069 
3070 	bcopy(sopt->sopt_val, buf, valsize);
3071 	return (0);
3072 }
3073 
3074 /*
3075  * Kernel version of setsockopt(2).
3076  *
3077  * XXX: optlen is size_t, not socklen_t
3078  */
3079 int
3080 so_setsockopt(struct socket *so, int level, int optname, void *optval,
3081     size_t optlen)
3082 {
3083 	struct sockopt sopt;
3084 
3085 	sopt.sopt_level = level;
3086 	sopt.sopt_name = optname;
3087 	sopt.sopt_dir = SOPT_SET;
3088 	sopt.sopt_val = optval;
3089 	sopt.sopt_valsize = optlen;
3090 	sopt.sopt_td = NULL;
3091 	return (sosetopt(so, &sopt));
3092 }
3093 
3094 int
3095 sosetopt(struct socket *so, struct sockopt *sopt)
3096 {
3097 	int	error, optval;
3098 	struct	linger l;
3099 	struct	timeval tv;
3100 	sbintime_t val, *valp;
3101 	uint32_t val32;
3102 #ifdef MAC
3103 	struct mac extmac;
3104 #endif
3105 
3106 	CURVNET_SET(so->so_vnet);
3107 	error = 0;
3108 	if (sopt->sopt_level != SOL_SOCKET) {
3109 		if (so->so_proto->pr_ctloutput != NULL)
3110 			error = (*so->so_proto->pr_ctloutput)(so, sopt);
3111 		else
3112 			error = ENOPROTOOPT;
3113 	} else {
3114 		switch (sopt->sopt_name) {
3115 		case SO_ACCEPTFILTER:
3116 			error = accept_filt_setopt(so, sopt);
3117 			if (error)
3118 				goto bad;
3119 			break;
3120 
3121 		case SO_LINGER:
3122 			error = sooptcopyin(sopt, &l, sizeof l, sizeof l);
3123 			if (error)
3124 				goto bad;
3125 			if (l.l_linger < 0 ||
3126 			    l.l_linger > USHRT_MAX ||
3127 			    l.l_linger > (INT_MAX / hz)) {
3128 				error = EDOM;
3129 				goto bad;
3130 			}
3131 			SOCK_LOCK(so);
3132 			so->so_linger = l.l_linger;
3133 			if (l.l_onoff)
3134 				so->so_options |= SO_LINGER;
3135 			else
3136 				so->so_options &= ~SO_LINGER;
3137 			SOCK_UNLOCK(so);
3138 			break;
3139 
3140 		case SO_DEBUG:
3141 		case SO_KEEPALIVE:
3142 		case SO_DONTROUTE:
3143 		case SO_USELOOPBACK:
3144 		case SO_BROADCAST:
3145 		case SO_REUSEADDR:
3146 		case SO_REUSEPORT:
3147 		case SO_REUSEPORT_LB:
3148 		case SO_OOBINLINE:
3149 		case SO_TIMESTAMP:
3150 		case SO_BINTIME:
3151 		case SO_NOSIGPIPE:
3152 		case SO_NO_DDP:
3153 		case SO_NO_OFFLOAD:
3154 		case SO_RERROR:
3155 			error = sooptcopyin(sopt, &optval, sizeof optval,
3156 			    sizeof optval);
3157 			if (error)
3158 				goto bad;
3159 			SOCK_LOCK(so);
3160 			if (optval)
3161 				so->so_options |= sopt->sopt_name;
3162 			else
3163 				so->so_options &= ~sopt->sopt_name;
3164 			SOCK_UNLOCK(so);
3165 			break;
3166 
3167 		case SO_SETFIB:
3168 			error = sooptcopyin(sopt, &optval, sizeof optval,
3169 			    sizeof optval);
3170 			if (error)
3171 				goto bad;
3172 
3173 			if (optval < 0 || optval >= rt_numfibs) {
3174 				error = EINVAL;
3175 				goto bad;
3176 			}
3177 			if (((so->so_proto->pr_domain->dom_family == PF_INET) ||
3178 			   (so->so_proto->pr_domain->dom_family == PF_INET6) ||
3179 			   (so->so_proto->pr_domain->dom_family == PF_ROUTE)))
3180 				so->so_fibnum = optval;
3181 			else
3182 				so->so_fibnum = 0;
3183 			break;
3184 
3185 		case SO_USER_COOKIE:
3186 			error = sooptcopyin(sopt, &val32, sizeof val32,
3187 			    sizeof val32);
3188 			if (error)
3189 				goto bad;
3190 			so->so_user_cookie = val32;
3191 			break;
3192 
3193 		case SO_SNDBUF:
3194 		case SO_RCVBUF:
3195 		case SO_SNDLOWAT:
3196 		case SO_RCVLOWAT:
3197 			error = so->so_proto->pr_setsbopt(so, sopt);
3198 			if (error)
3199 				goto bad;
3200 			break;
3201 
3202 		case SO_SNDTIMEO:
3203 		case SO_RCVTIMEO:
3204 #ifdef COMPAT_FREEBSD32
3205 			if (SV_CURPROC_FLAG(SV_ILP32)) {
3206 				struct timeval32 tv32;
3207 
3208 				error = sooptcopyin(sopt, &tv32, sizeof tv32,
3209 				    sizeof tv32);
3210 				CP(tv32, tv, tv_sec);
3211 				CP(tv32, tv, tv_usec);
3212 			} else
3213 #endif
3214 				error = sooptcopyin(sopt, &tv, sizeof tv,
3215 				    sizeof tv);
3216 			if (error)
3217 				goto bad;
3218 			if (tv.tv_sec < 0 || tv.tv_usec < 0 ||
3219 			    tv.tv_usec >= 1000000) {
3220 				error = EDOM;
3221 				goto bad;
3222 			}
3223 			if (tv.tv_sec > INT32_MAX)
3224 				val = SBT_MAX;
3225 			else
3226 				val = tvtosbt(tv);
3227 			SOCK_LOCK(so);
3228 			valp = sopt->sopt_name == SO_SNDTIMEO ?
3229 			    (SOLISTENING(so) ? &so->sol_sbsnd_timeo :
3230 			    &so->so_snd.sb_timeo) :
3231 			    (SOLISTENING(so) ? &so->sol_sbrcv_timeo :
3232 			    &so->so_rcv.sb_timeo);
3233 			*valp = val;
3234 			SOCK_UNLOCK(so);
3235 			break;
3236 
3237 		case SO_LABEL:
3238 #ifdef MAC
3239 			error = sooptcopyin(sopt, &extmac, sizeof extmac,
3240 			    sizeof extmac);
3241 			if (error)
3242 				goto bad;
3243 			error = mac_setsockopt_label(sopt->sopt_td->td_ucred,
3244 			    so, &extmac);
3245 #else
3246 			error = EOPNOTSUPP;
3247 #endif
3248 			break;
3249 
3250 		case SO_TS_CLOCK:
3251 			error = sooptcopyin(sopt, &optval, sizeof optval,
3252 			    sizeof optval);
3253 			if (error)
3254 				goto bad;
3255 			if (optval < 0 || optval > SO_TS_CLOCK_MAX) {
3256 				error = EINVAL;
3257 				goto bad;
3258 			}
3259 			so->so_ts_clock = optval;
3260 			break;
3261 
3262 		case SO_MAX_PACING_RATE:
3263 			error = sooptcopyin(sopt, &val32, sizeof(val32),
3264 			    sizeof(val32));
3265 			if (error)
3266 				goto bad;
3267 			so->so_max_pacing_rate = val32;
3268 			break;
3269 
3270 		default:
3271 			if (V_socket_hhh[HHOOK_SOCKET_OPT]->hhh_nhooks > 0)
3272 				error = hhook_run_socket(so, sopt,
3273 				    HHOOK_SOCKET_OPT);
3274 			else
3275 				error = ENOPROTOOPT;
3276 			break;
3277 		}
3278 		if (error == 0 && so->so_proto->pr_ctloutput != NULL)
3279 			(void)(*so->so_proto->pr_ctloutput)(so, sopt);
3280 	}
3281 bad:
3282 	CURVNET_RESTORE();
3283 	return (error);
3284 }
3285 
3286 /*
3287  * Helper routine for getsockopt.
3288  */
3289 int
3290 sooptcopyout(struct sockopt *sopt, const void *buf, size_t len)
3291 {
3292 	int	error;
3293 	size_t	valsize;
3294 
3295 	error = 0;
3296 
3297 	/*
3298 	 * Documented get behavior is that we always return a value, possibly
3299 	 * truncated to fit in the user's buffer.  Traditional behavior is
3300 	 * that we always tell the user precisely how much we copied, rather
3301 	 * than something useful like the total amount we had available for
3302 	 * her.  Note that this interface is not idempotent; the entire
3303 	 * answer must be generated ahead of time.
3304 	 */
3305 	valsize = min(len, sopt->sopt_valsize);
3306 	sopt->sopt_valsize = valsize;
3307 	if (sopt->sopt_val != NULL) {
3308 		if (sopt->sopt_td != NULL)
3309 			error = copyout(buf, sopt->sopt_val, valsize);
3310 		else
3311 			bcopy(buf, sopt->sopt_val, valsize);
3312 	}
3313 	return (error);
3314 }
3315 
3316 int
3317 sogetopt(struct socket *so, struct sockopt *sopt)
3318 {
3319 	int	error, optval;
3320 	struct	linger l;
3321 	struct	timeval tv;
3322 #ifdef MAC
3323 	struct mac extmac;
3324 #endif
3325 
3326 	CURVNET_SET(so->so_vnet);
3327 	error = 0;
3328 	if (sopt->sopt_level != SOL_SOCKET) {
3329 		if (so->so_proto->pr_ctloutput != NULL)
3330 			error = (*so->so_proto->pr_ctloutput)(so, sopt);
3331 		else
3332 			error = ENOPROTOOPT;
3333 		CURVNET_RESTORE();
3334 		return (error);
3335 	} else {
3336 		switch (sopt->sopt_name) {
3337 		case SO_ACCEPTFILTER:
3338 			error = accept_filt_getopt(so, sopt);
3339 			break;
3340 
3341 		case SO_LINGER:
3342 			SOCK_LOCK(so);
3343 			l.l_onoff = so->so_options & SO_LINGER;
3344 			l.l_linger = so->so_linger;
3345 			SOCK_UNLOCK(so);
3346 			error = sooptcopyout(sopt, &l, sizeof l);
3347 			break;
3348 
3349 		case SO_USELOOPBACK:
3350 		case SO_DONTROUTE:
3351 		case SO_DEBUG:
3352 		case SO_KEEPALIVE:
3353 		case SO_REUSEADDR:
3354 		case SO_REUSEPORT:
3355 		case SO_REUSEPORT_LB:
3356 		case SO_BROADCAST:
3357 		case SO_OOBINLINE:
3358 		case SO_ACCEPTCONN:
3359 		case SO_TIMESTAMP:
3360 		case SO_BINTIME:
3361 		case SO_NOSIGPIPE:
3362 		case SO_NO_DDP:
3363 		case SO_NO_OFFLOAD:
3364 		case SO_RERROR:
3365 			optval = so->so_options & sopt->sopt_name;
3366 integer:
3367 			error = sooptcopyout(sopt, &optval, sizeof optval);
3368 			break;
3369 
3370 		case SO_DOMAIN:
3371 			optval = so->so_proto->pr_domain->dom_family;
3372 			goto integer;
3373 
3374 		case SO_TYPE:
3375 			optval = so->so_type;
3376 			goto integer;
3377 
3378 		case SO_PROTOCOL:
3379 			optval = so->so_proto->pr_protocol;
3380 			goto integer;
3381 
3382 		case SO_ERROR:
3383 			SOCK_LOCK(so);
3384 			if (so->so_error) {
3385 				optval = so->so_error;
3386 				so->so_error = 0;
3387 			} else {
3388 				optval = so->so_rerror;
3389 				so->so_rerror = 0;
3390 			}
3391 			SOCK_UNLOCK(so);
3392 			goto integer;
3393 
3394 		case SO_SNDBUF:
3395 			optval = SOLISTENING(so) ? so->sol_sbsnd_hiwat :
3396 			    so->so_snd.sb_hiwat;
3397 			goto integer;
3398 
3399 		case SO_RCVBUF:
3400 			optval = SOLISTENING(so) ? so->sol_sbrcv_hiwat :
3401 			    so->so_rcv.sb_hiwat;
3402 			goto integer;
3403 
3404 		case SO_SNDLOWAT:
3405 			optval = SOLISTENING(so) ? so->sol_sbsnd_lowat :
3406 			    so->so_snd.sb_lowat;
3407 			goto integer;
3408 
3409 		case SO_RCVLOWAT:
3410 			optval = SOLISTENING(so) ? so->sol_sbrcv_lowat :
3411 			    so->so_rcv.sb_lowat;
3412 			goto integer;
3413 
3414 		case SO_SNDTIMEO:
3415 		case SO_RCVTIMEO:
3416 			SOCK_LOCK(so);
3417 			tv = sbttotv(sopt->sopt_name == SO_SNDTIMEO ?
3418 			    (SOLISTENING(so) ? so->sol_sbsnd_timeo :
3419 			    so->so_snd.sb_timeo) :
3420 			    (SOLISTENING(so) ? so->sol_sbrcv_timeo :
3421 			    so->so_rcv.sb_timeo));
3422 			SOCK_UNLOCK(so);
3423 #ifdef COMPAT_FREEBSD32
3424 			if (SV_CURPROC_FLAG(SV_ILP32)) {
3425 				struct timeval32 tv32;
3426 
3427 				CP(tv, tv32, tv_sec);
3428 				CP(tv, tv32, tv_usec);
3429 				error = sooptcopyout(sopt, &tv32, sizeof tv32);
3430 			} else
3431 #endif
3432 				error = sooptcopyout(sopt, &tv, sizeof tv);
3433 			break;
3434 
3435 		case SO_LABEL:
3436 #ifdef MAC
3437 			error = sooptcopyin(sopt, &extmac, sizeof(extmac),
3438 			    sizeof(extmac));
3439 			if (error)
3440 				goto bad;
3441 			error = mac_getsockopt_label(sopt->sopt_td->td_ucred,
3442 			    so, &extmac);
3443 			if (error)
3444 				goto bad;
3445 			error = sooptcopyout(sopt, &extmac, sizeof extmac);
3446 #else
3447 			error = EOPNOTSUPP;
3448 #endif
3449 			break;
3450 
3451 		case SO_PEERLABEL:
3452 #ifdef MAC
3453 			error = sooptcopyin(sopt, &extmac, sizeof(extmac),
3454 			    sizeof(extmac));
3455 			if (error)
3456 				goto bad;
3457 			error = mac_getsockopt_peerlabel(
3458 			    sopt->sopt_td->td_ucred, so, &extmac);
3459 			if (error)
3460 				goto bad;
3461 			error = sooptcopyout(sopt, &extmac, sizeof extmac);
3462 #else
3463 			error = EOPNOTSUPP;
3464 #endif
3465 			break;
3466 
3467 		case SO_LISTENQLIMIT:
3468 			optval = SOLISTENING(so) ? so->sol_qlimit : 0;
3469 			goto integer;
3470 
3471 		case SO_LISTENQLEN:
3472 			optval = SOLISTENING(so) ? so->sol_qlen : 0;
3473 			goto integer;
3474 
3475 		case SO_LISTENINCQLEN:
3476 			optval = SOLISTENING(so) ? so->sol_incqlen : 0;
3477 			goto integer;
3478 
3479 		case SO_TS_CLOCK:
3480 			optval = so->so_ts_clock;
3481 			goto integer;
3482 
3483 		case SO_MAX_PACING_RATE:
3484 			optval = so->so_max_pacing_rate;
3485 			goto integer;
3486 
3487 		default:
3488 			if (V_socket_hhh[HHOOK_SOCKET_OPT]->hhh_nhooks > 0)
3489 				error = hhook_run_socket(so, sopt,
3490 				    HHOOK_SOCKET_OPT);
3491 			else
3492 				error = ENOPROTOOPT;
3493 			break;
3494 		}
3495 	}
3496 #ifdef MAC
3497 bad:
3498 #endif
3499 	CURVNET_RESTORE();
3500 	return (error);
3501 }
3502 
3503 int
3504 soopt_getm(struct sockopt *sopt, struct mbuf **mp)
3505 {
3506 	struct mbuf *m, *m_prev;
3507 	int sopt_size = sopt->sopt_valsize;
3508 
3509 	MGET(m, sopt->sopt_td ? M_WAITOK : M_NOWAIT, MT_DATA);
3510 	if (m == NULL)
3511 		return ENOBUFS;
3512 	if (sopt_size > MLEN) {
3513 		MCLGET(m, sopt->sopt_td ? M_WAITOK : M_NOWAIT);
3514 		if ((m->m_flags & M_EXT) == 0) {
3515 			m_free(m);
3516 			return ENOBUFS;
3517 		}
3518 		m->m_len = min(MCLBYTES, sopt_size);
3519 	} else {
3520 		m->m_len = min(MLEN, sopt_size);
3521 	}
3522 	sopt_size -= m->m_len;
3523 	*mp = m;
3524 	m_prev = m;
3525 
3526 	while (sopt_size) {
3527 		MGET(m, sopt->sopt_td ? M_WAITOK : M_NOWAIT, MT_DATA);
3528 		if (m == NULL) {
3529 			m_freem(*mp);
3530 			return ENOBUFS;
3531 		}
3532 		if (sopt_size > MLEN) {
3533 			MCLGET(m, sopt->sopt_td != NULL ? M_WAITOK :
3534 			    M_NOWAIT);
3535 			if ((m->m_flags & M_EXT) == 0) {
3536 				m_freem(m);
3537 				m_freem(*mp);
3538 				return ENOBUFS;
3539 			}
3540 			m->m_len = min(MCLBYTES, sopt_size);
3541 		} else {
3542 			m->m_len = min(MLEN, sopt_size);
3543 		}
3544 		sopt_size -= m->m_len;
3545 		m_prev->m_next = m;
3546 		m_prev = m;
3547 	}
3548 	return (0);
3549 }
3550 
3551 int
3552 soopt_mcopyin(struct sockopt *sopt, struct mbuf *m)
3553 {
3554 	struct mbuf *m0 = m;
3555 
3556 	if (sopt->sopt_val == NULL)
3557 		return (0);
3558 	while (m != NULL && sopt->sopt_valsize >= m->m_len) {
3559 		if (sopt->sopt_td != NULL) {
3560 			int error;
3561 
3562 			error = copyin(sopt->sopt_val, mtod(m, char *),
3563 			    m->m_len);
3564 			if (error != 0) {
3565 				m_freem(m0);
3566 				return(error);
3567 			}
3568 		} else
3569 			bcopy(sopt->sopt_val, mtod(m, char *), m->m_len);
3570 		sopt->sopt_valsize -= m->m_len;
3571 		sopt->sopt_val = (char *)sopt->sopt_val + m->m_len;
3572 		m = m->m_next;
3573 	}
3574 	if (m != NULL) /* should be allocated enoughly at ip6_sooptmcopyin() */
3575 		panic("ip6_sooptmcopyin");
3576 	return (0);
3577 }
3578 
3579 int
3580 soopt_mcopyout(struct sockopt *sopt, struct mbuf *m)
3581 {
3582 	struct mbuf *m0 = m;
3583 	size_t valsize = 0;
3584 
3585 	if (sopt->sopt_val == NULL)
3586 		return (0);
3587 	while (m != NULL && sopt->sopt_valsize >= m->m_len) {
3588 		if (sopt->sopt_td != NULL) {
3589 			int error;
3590 
3591 			error = copyout(mtod(m, char *), sopt->sopt_val,
3592 			    m->m_len);
3593 			if (error != 0) {
3594 				m_freem(m0);
3595 				return(error);
3596 			}
3597 		} else
3598 			bcopy(mtod(m, char *), sopt->sopt_val, m->m_len);
3599 		sopt->sopt_valsize -= m->m_len;
3600 		sopt->sopt_val = (char *)sopt->sopt_val + m->m_len;
3601 		valsize += m->m_len;
3602 		m = m->m_next;
3603 	}
3604 	if (m != NULL) {
3605 		/* enough soopt buffer should be given from user-land */
3606 		m_freem(m0);
3607 		return(EINVAL);
3608 	}
3609 	sopt->sopt_valsize = valsize;
3610 	return (0);
3611 }
3612 
3613 /*
3614  * sohasoutofband(): protocol notifies socket layer of the arrival of new
3615  * out-of-band data, which will then notify socket consumers.
3616  */
3617 void
3618 sohasoutofband(struct socket *so)
3619 {
3620 
3621 	if (so->so_sigio != NULL)
3622 		pgsigio(&so->so_sigio, SIGURG, 0);
3623 	selwakeuppri(&so->so_rdsel, PSOCK);
3624 }
3625 
3626 int
3627 sopoll(struct socket *so, int events, struct ucred *active_cred,
3628     struct thread *td)
3629 {
3630 
3631 	/*
3632 	 * We do not need to set or assert curvnet as long as everyone uses
3633 	 * sopoll_generic().
3634 	 */
3635 	return (so->so_proto->pr_sopoll(so, events, active_cred, td));
3636 }
3637 
3638 int
3639 sopoll_generic(struct socket *so, int events, struct ucred *active_cred,
3640     struct thread *td)
3641 {
3642 	int revents;
3643 
3644 	SOCK_LOCK(so);
3645 	if (SOLISTENING(so)) {
3646 		if (!(events & (POLLIN | POLLRDNORM)))
3647 			revents = 0;
3648 		else if (!TAILQ_EMPTY(&so->sol_comp))
3649 			revents = events & (POLLIN | POLLRDNORM);
3650 		else if ((events & POLLINIGNEOF) == 0 && so->so_error)
3651 			revents = (events & (POLLIN | POLLRDNORM)) | POLLHUP;
3652 		else {
3653 			selrecord(td, &so->so_rdsel);
3654 			revents = 0;
3655 		}
3656 	} else {
3657 		revents = 0;
3658 		SOCK_SENDBUF_LOCK(so);
3659 		SOCK_RECVBUF_LOCK(so);
3660 		if (events & (POLLIN | POLLRDNORM))
3661 			if (soreadabledata(so))
3662 				revents |= events & (POLLIN | POLLRDNORM);
3663 		if (events & (POLLOUT | POLLWRNORM))
3664 			if (sowriteable(so))
3665 				revents |= events & (POLLOUT | POLLWRNORM);
3666 		if (events & (POLLPRI | POLLRDBAND))
3667 			if (so->so_oobmark ||
3668 			    (so->so_rcv.sb_state & SBS_RCVATMARK))
3669 				revents |= events & (POLLPRI | POLLRDBAND);
3670 		if ((events & POLLINIGNEOF) == 0) {
3671 			if (so->so_rcv.sb_state & SBS_CANTRCVMORE) {
3672 				revents |= events & (POLLIN | POLLRDNORM);
3673 				if (so->so_snd.sb_state & SBS_CANTSENDMORE)
3674 					revents |= POLLHUP;
3675 			}
3676 		}
3677 		if (so->so_rcv.sb_state & SBS_CANTRCVMORE)
3678 			revents |= events & POLLRDHUP;
3679 		if (revents == 0) {
3680 			if (events &
3681 			    (POLLIN | POLLPRI | POLLRDNORM | POLLRDBAND | POLLRDHUP)) {
3682 				selrecord(td, &so->so_rdsel);
3683 				so->so_rcv.sb_flags |= SB_SEL;
3684 			}
3685 			if (events & (POLLOUT | POLLWRNORM)) {
3686 				selrecord(td, &so->so_wrsel);
3687 				so->so_snd.sb_flags |= SB_SEL;
3688 			}
3689 		}
3690 		SOCK_RECVBUF_UNLOCK(so);
3691 		SOCK_SENDBUF_UNLOCK(so);
3692 	}
3693 	SOCK_UNLOCK(so);
3694 	return (revents);
3695 }
3696 
3697 int
3698 soo_kqfilter(struct file *fp, struct knote *kn)
3699 {
3700 	struct socket *so = kn->kn_fp->f_data;
3701 	struct sockbuf *sb;
3702 	sb_which which;
3703 	struct knlist *knl;
3704 
3705 	switch (kn->kn_filter) {
3706 	case EVFILT_READ:
3707 		kn->kn_fop = &soread_filtops;
3708 		knl = &so->so_rdsel.si_note;
3709 		sb = &so->so_rcv;
3710 		which = SO_RCV;
3711 		break;
3712 	case EVFILT_WRITE:
3713 		kn->kn_fop = &sowrite_filtops;
3714 		knl = &so->so_wrsel.si_note;
3715 		sb = &so->so_snd;
3716 		which = SO_SND;
3717 		break;
3718 	case EVFILT_EMPTY:
3719 		kn->kn_fop = &soempty_filtops;
3720 		knl = &so->so_wrsel.si_note;
3721 		sb = &so->so_snd;
3722 		which = SO_SND;
3723 		break;
3724 	default:
3725 		return (EINVAL);
3726 	}
3727 
3728 	SOCK_LOCK(so);
3729 	if (SOLISTENING(so)) {
3730 		knlist_add(knl, kn, 1);
3731 	} else {
3732 		SOCK_BUF_LOCK(so, which);
3733 		knlist_add(knl, kn, 1);
3734 		sb->sb_flags |= SB_KNOTE;
3735 		SOCK_BUF_UNLOCK(so, which);
3736 	}
3737 	SOCK_UNLOCK(so);
3738 	return (0);
3739 }
3740 
3741 static void
3742 filt_sordetach(struct knote *kn)
3743 {
3744 	struct socket *so = kn->kn_fp->f_data;
3745 
3746 	so_rdknl_lock(so);
3747 	knlist_remove(&so->so_rdsel.si_note, kn, 1);
3748 	if (!SOLISTENING(so) && knlist_empty(&so->so_rdsel.si_note))
3749 		so->so_rcv.sb_flags &= ~SB_KNOTE;
3750 	so_rdknl_unlock(so);
3751 }
3752 
3753 /*ARGSUSED*/
3754 static int
3755 filt_soread(struct knote *kn, long hint)
3756 {
3757 	struct socket *so;
3758 
3759 	so = kn->kn_fp->f_data;
3760 
3761 	if (SOLISTENING(so)) {
3762 		SOCK_LOCK_ASSERT(so);
3763 		kn->kn_data = so->sol_qlen;
3764 		if (so->so_error) {
3765 			kn->kn_flags |= EV_EOF;
3766 			kn->kn_fflags = so->so_error;
3767 			return (1);
3768 		}
3769 		return (!TAILQ_EMPTY(&so->sol_comp));
3770 	}
3771 
3772 	SOCK_RECVBUF_LOCK_ASSERT(so);
3773 
3774 	kn->kn_data = sbavail(&so->so_rcv) - so->so_rcv.sb_ctl;
3775 	if (so->so_rcv.sb_state & SBS_CANTRCVMORE) {
3776 		kn->kn_flags |= EV_EOF;
3777 		kn->kn_fflags = so->so_error;
3778 		return (1);
3779 	} else if (so->so_error || so->so_rerror)
3780 		return (1);
3781 
3782 	if (kn->kn_sfflags & NOTE_LOWAT) {
3783 		if (kn->kn_data >= kn->kn_sdata)
3784 			return (1);
3785 	} else if (sbavail(&so->so_rcv) >= so->so_rcv.sb_lowat)
3786 		return (1);
3787 
3788 	/* This hook returning non-zero indicates an event, not error */
3789 	return (hhook_run_socket(so, NULL, HHOOK_FILT_SOREAD));
3790 }
3791 
3792 static void
3793 filt_sowdetach(struct knote *kn)
3794 {
3795 	struct socket *so = kn->kn_fp->f_data;
3796 
3797 	so_wrknl_lock(so);
3798 	knlist_remove(&so->so_wrsel.si_note, kn, 1);
3799 	if (!SOLISTENING(so) && knlist_empty(&so->so_wrsel.si_note))
3800 		so->so_snd.sb_flags &= ~SB_KNOTE;
3801 	so_wrknl_unlock(so);
3802 }
3803 
3804 /*ARGSUSED*/
3805 static int
3806 filt_sowrite(struct knote *kn, long hint)
3807 {
3808 	struct socket *so;
3809 
3810 	so = kn->kn_fp->f_data;
3811 
3812 	if (SOLISTENING(so))
3813 		return (0);
3814 
3815 	SOCK_SENDBUF_LOCK_ASSERT(so);
3816 	kn->kn_data = sbspace(&so->so_snd);
3817 
3818 	hhook_run_socket(so, kn, HHOOK_FILT_SOWRITE);
3819 
3820 	if (so->so_snd.sb_state & SBS_CANTSENDMORE) {
3821 		kn->kn_flags |= EV_EOF;
3822 		kn->kn_fflags = so->so_error;
3823 		return (1);
3824 	} else if (so->so_error)	/* temporary udp error */
3825 		return (1);
3826 	else if (((so->so_state & SS_ISCONNECTED) == 0) &&
3827 	    (so->so_proto->pr_flags & PR_CONNREQUIRED))
3828 		return (0);
3829 	else if (kn->kn_sfflags & NOTE_LOWAT)
3830 		return (kn->kn_data >= kn->kn_sdata);
3831 	else
3832 		return (kn->kn_data >= so->so_snd.sb_lowat);
3833 }
3834 
3835 static int
3836 filt_soempty(struct knote *kn, long hint)
3837 {
3838 	struct socket *so;
3839 
3840 	so = kn->kn_fp->f_data;
3841 
3842 	if (SOLISTENING(so))
3843 		return (1);
3844 
3845 	SOCK_SENDBUF_LOCK_ASSERT(so);
3846 	kn->kn_data = sbused(&so->so_snd);
3847 
3848 	if (kn->kn_data == 0)
3849 		return (1);
3850 	else
3851 		return (0);
3852 }
3853 
3854 int
3855 socheckuid(struct socket *so, uid_t uid)
3856 {
3857 
3858 	if (so == NULL)
3859 		return (EPERM);
3860 	if (so->so_cred->cr_uid != uid)
3861 		return (EPERM);
3862 	return (0);
3863 }
3864 
3865 /*
3866  * These functions are used by protocols to notify the socket layer (and its
3867  * consumers) of state changes in the sockets driven by protocol-side events.
3868  */
3869 
3870 /*
3871  * Procedures to manipulate state flags of socket and do appropriate wakeups.
3872  *
3873  * Normal sequence from the active (originating) side is that
3874  * soisconnecting() is called during processing of connect() call, resulting
3875  * in an eventual call to soisconnected() if/when the connection is
3876  * established.  When the connection is torn down soisdisconnecting() is
3877  * called during processing of disconnect() call, and soisdisconnected() is
3878  * called when the connection to the peer is totally severed.  The semantics
3879  * of these routines are such that connectionless protocols can call
3880  * soisconnected() and soisdisconnected() only, bypassing the in-progress
3881  * calls when setting up a ``connection'' takes no time.
3882  *
3883  * From the passive side, a socket is created with two queues of sockets:
3884  * so_incomp for connections in progress and so_comp for connections already
3885  * made and awaiting user acceptance.  As a protocol is preparing incoming
3886  * connections, it creates a socket structure queued on so_incomp by calling
3887  * sonewconn().  When the connection is established, soisconnected() is
3888  * called, and transfers the socket structure to so_comp, making it available
3889  * to accept().
3890  *
3891  * If a socket is closed with sockets on either so_incomp or so_comp, these
3892  * sockets are dropped.
3893  *
3894  * If higher-level protocols are implemented in the kernel, the wakeups done
3895  * here will sometimes cause software-interrupt process scheduling.
3896  */
3897 void
3898 soisconnecting(struct socket *so)
3899 {
3900 
3901 	SOCK_LOCK(so);
3902 	so->so_state &= ~(SS_ISCONNECTED|SS_ISDISCONNECTING);
3903 	so->so_state |= SS_ISCONNECTING;
3904 	SOCK_UNLOCK(so);
3905 }
3906 
3907 void
3908 soisconnected(struct socket *so)
3909 {
3910 	bool last __diagused;
3911 
3912 	SOCK_LOCK(so);
3913 	so->so_state &= ~(SS_ISCONNECTING|SS_ISDISCONNECTING|SS_ISCONFIRMING);
3914 	so->so_state |= SS_ISCONNECTED;
3915 
3916 	if (so->so_qstate == SQ_INCOMP) {
3917 		struct socket *head = so->so_listen;
3918 		int ret;
3919 
3920 		KASSERT(head, ("%s: so %p on incomp of NULL", __func__, so));
3921 		/*
3922 		 * Promoting a socket from incomplete queue to complete, we
3923 		 * need to go through reverse order of locking.  We first do
3924 		 * trylock, and if that doesn't succeed, we go the hard way
3925 		 * leaving a reference and rechecking consistency after proper
3926 		 * locking.
3927 		 */
3928 		if (__predict_false(SOLISTEN_TRYLOCK(head) == 0)) {
3929 			soref(head);
3930 			SOCK_UNLOCK(so);
3931 			SOLISTEN_LOCK(head);
3932 			SOCK_LOCK(so);
3933 			if (__predict_false(head != so->so_listen)) {
3934 				/*
3935 				 * The socket went off the listen queue,
3936 				 * should be lost race to close(2) of sol.
3937 				 * The socket is about to soabort().
3938 				 */
3939 				SOCK_UNLOCK(so);
3940 				sorele_locked(head);
3941 				return;
3942 			}
3943 			last = refcount_release(&head->so_count);
3944 			KASSERT(!last, ("%s: released last reference for %p",
3945 			    __func__, head));
3946 		}
3947 again:
3948 		if ((so->so_options & SO_ACCEPTFILTER) == 0) {
3949 			TAILQ_REMOVE(&head->sol_incomp, so, so_list);
3950 			head->sol_incqlen--;
3951 			TAILQ_INSERT_TAIL(&head->sol_comp, so, so_list);
3952 			head->sol_qlen++;
3953 			so->so_qstate = SQ_COMP;
3954 			SOCK_UNLOCK(so);
3955 			solisten_wakeup(head);	/* unlocks */
3956 		} else {
3957 			SOCK_RECVBUF_LOCK(so);
3958 			soupcall_set(so, SO_RCV,
3959 			    head->sol_accept_filter->accf_callback,
3960 			    head->sol_accept_filter_arg);
3961 			so->so_options &= ~SO_ACCEPTFILTER;
3962 			ret = head->sol_accept_filter->accf_callback(so,
3963 			    head->sol_accept_filter_arg, M_NOWAIT);
3964 			if (ret == SU_ISCONNECTED) {
3965 				soupcall_clear(so, SO_RCV);
3966 				SOCK_RECVBUF_UNLOCK(so);
3967 				goto again;
3968 			}
3969 			SOCK_RECVBUF_UNLOCK(so);
3970 			SOCK_UNLOCK(so);
3971 			SOLISTEN_UNLOCK(head);
3972 		}
3973 		return;
3974 	}
3975 	SOCK_UNLOCK(so);
3976 	wakeup(&so->so_timeo);
3977 	sorwakeup(so);
3978 	sowwakeup(so);
3979 }
3980 
3981 void
3982 soisdisconnecting(struct socket *so)
3983 {
3984 
3985 	SOCK_LOCK(so);
3986 	so->so_state &= ~SS_ISCONNECTING;
3987 	so->so_state |= SS_ISDISCONNECTING;
3988 
3989 	if (!SOLISTENING(so)) {
3990 		SOCK_RECVBUF_LOCK(so);
3991 		socantrcvmore_locked(so);
3992 		SOCK_SENDBUF_LOCK(so);
3993 		socantsendmore_locked(so);
3994 	}
3995 	SOCK_UNLOCK(so);
3996 	wakeup(&so->so_timeo);
3997 }
3998 
3999 void
4000 soisdisconnected(struct socket *so)
4001 {
4002 
4003 	SOCK_LOCK(so);
4004 
4005 	/*
4006 	 * There is at least one reader of so_state that does not
4007 	 * acquire socket lock, namely soreceive_generic().  Ensure
4008 	 * that it never sees all flags that track connection status
4009 	 * cleared, by ordering the update with a barrier semantic of
4010 	 * our release thread fence.
4011 	 */
4012 	so->so_state |= SS_ISDISCONNECTED;
4013 	atomic_thread_fence_rel();
4014 	so->so_state &= ~(SS_ISCONNECTING|SS_ISCONNECTED|SS_ISDISCONNECTING);
4015 
4016 	if (!SOLISTENING(so)) {
4017 		SOCK_UNLOCK(so);
4018 		SOCK_RECVBUF_LOCK(so);
4019 		socantrcvmore_locked(so);
4020 		SOCK_SENDBUF_LOCK(so);
4021 		sbdrop_locked(&so->so_snd, sbused(&so->so_snd));
4022 		socantsendmore_locked(so);
4023 	} else
4024 		SOCK_UNLOCK(so);
4025 	wakeup(&so->so_timeo);
4026 }
4027 
4028 int
4029 soiolock(struct socket *so, struct sx *sx, int flags)
4030 {
4031 	int error;
4032 
4033 	KASSERT((flags & SBL_VALID) == flags,
4034 	    ("soiolock: invalid flags %#x", flags));
4035 
4036 	if ((flags & SBL_WAIT) != 0) {
4037 		if ((flags & SBL_NOINTR) != 0) {
4038 			sx_xlock(sx);
4039 		} else {
4040 			error = sx_xlock_sig(sx);
4041 			if (error != 0)
4042 				return (error);
4043 		}
4044 	} else if (!sx_try_xlock(sx)) {
4045 		return (EWOULDBLOCK);
4046 	}
4047 
4048 	if (__predict_false(SOLISTENING(so))) {
4049 		sx_xunlock(sx);
4050 		return (ENOTCONN);
4051 	}
4052 	return (0);
4053 }
4054 
4055 void
4056 soiounlock(struct sx *sx)
4057 {
4058 	sx_xunlock(sx);
4059 }
4060 
4061 /*
4062  * Make a copy of a sockaddr in a malloced buffer of type M_SONAME.
4063  */
4064 struct sockaddr *
4065 sodupsockaddr(const struct sockaddr *sa, int mflags)
4066 {
4067 	struct sockaddr *sa2;
4068 
4069 	sa2 = malloc(sa->sa_len, M_SONAME, mflags);
4070 	if (sa2)
4071 		bcopy(sa, sa2, sa->sa_len);
4072 	return sa2;
4073 }
4074 
4075 /*
4076  * Register per-socket destructor.
4077  */
4078 void
4079 sodtor_set(struct socket *so, so_dtor_t *func)
4080 {
4081 
4082 	SOCK_LOCK_ASSERT(so);
4083 	so->so_dtor = func;
4084 }
4085 
4086 /*
4087  * Register per-socket buffer upcalls.
4088  */
4089 void
4090 soupcall_set(struct socket *so, sb_which which, so_upcall_t func, void *arg)
4091 {
4092 	struct sockbuf *sb;
4093 
4094 	KASSERT(!SOLISTENING(so), ("%s: so %p listening", __func__, so));
4095 
4096 	switch (which) {
4097 	case SO_RCV:
4098 		sb = &so->so_rcv;
4099 		break;
4100 	case SO_SND:
4101 		sb = &so->so_snd;
4102 		break;
4103 	}
4104 	SOCK_BUF_LOCK_ASSERT(so, which);
4105 	sb->sb_upcall = func;
4106 	sb->sb_upcallarg = arg;
4107 	sb->sb_flags |= SB_UPCALL;
4108 }
4109 
4110 void
4111 soupcall_clear(struct socket *so, sb_which which)
4112 {
4113 	struct sockbuf *sb;
4114 
4115 	KASSERT(!SOLISTENING(so), ("%s: so %p listening", __func__, so));
4116 
4117 	switch (which) {
4118 	case SO_RCV:
4119 		sb = &so->so_rcv;
4120 		break;
4121 	case SO_SND:
4122 		sb = &so->so_snd;
4123 		break;
4124 	}
4125 	SOCK_BUF_LOCK_ASSERT(so, which);
4126 	KASSERT(sb->sb_upcall != NULL,
4127 	    ("%s: so %p no upcall to clear", __func__, so));
4128 	sb->sb_upcall = NULL;
4129 	sb->sb_upcallarg = NULL;
4130 	sb->sb_flags &= ~SB_UPCALL;
4131 }
4132 
4133 void
4134 solisten_upcall_set(struct socket *so, so_upcall_t func, void *arg)
4135 {
4136 
4137 	SOLISTEN_LOCK_ASSERT(so);
4138 	so->sol_upcall = func;
4139 	so->sol_upcallarg = arg;
4140 }
4141 
4142 static void
4143 so_rdknl_lock(void *arg)
4144 {
4145 	struct socket *so = arg;
4146 
4147 retry:
4148 	if (SOLISTENING(so)) {
4149 		SOLISTEN_LOCK(so);
4150 	} else {
4151 		SOCK_RECVBUF_LOCK(so);
4152 		if (__predict_false(SOLISTENING(so))) {
4153 			SOCK_RECVBUF_UNLOCK(so);
4154 			goto retry;
4155 		}
4156 	}
4157 }
4158 
4159 static void
4160 so_rdknl_unlock(void *arg)
4161 {
4162 	struct socket *so = arg;
4163 
4164 	if (SOLISTENING(so))
4165 		SOLISTEN_UNLOCK(so);
4166 	else
4167 		SOCK_RECVBUF_UNLOCK(so);
4168 }
4169 
4170 static void
4171 so_rdknl_assert_lock(void *arg, int what)
4172 {
4173 	struct socket *so = arg;
4174 
4175 	if (what == LA_LOCKED) {
4176 		if (SOLISTENING(so))
4177 			SOLISTEN_LOCK_ASSERT(so);
4178 		else
4179 			SOCK_RECVBUF_LOCK_ASSERT(so);
4180 	} else {
4181 		if (SOLISTENING(so))
4182 			SOLISTEN_UNLOCK_ASSERT(so);
4183 		else
4184 			SOCK_RECVBUF_UNLOCK_ASSERT(so);
4185 	}
4186 }
4187 
4188 static void
4189 so_wrknl_lock(void *arg)
4190 {
4191 	struct socket *so = arg;
4192 
4193 retry:
4194 	if (SOLISTENING(so)) {
4195 		SOLISTEN_LOCK(so);
4196 	} else {
4197 		SOCK_SENDBUF_LOCK(so);
4198 		if (__predict_false(SOLISTENING(so))) {
4199 			SOCK_SENDBUF_UNLOCK(so);
4200 			goto retry;
4201 		}
4202 	}
4203 }
4204 
4205 static void
4206 so_wrknl_unlock(void *arg)
4207 {
4208 	struct socket *so = arg;
4209 
4210 	if (SOLISTENING(so))
4211 		SOLISTEN_UNLOCK(so);
4212 	else
4213 		SOCK_SENDBUF_UNLOCK(so);
4214 }
4215 
4216 static void
4217 so_wrknl_assert_lock(void *arg, int what)
4218 {
4219 	struct socket *so = arg;
4220 
4221 	if (what == LA_LOCKED) {
4222 		if (SOLISTENING(so))
4223 			SOLISTEN_LOCK_ASSERT(so);
4224 		else
4225 			SOCK_SENDBUF_LOCK_ASSERT(so);
4226 	} else {
4227 		if (SOLISTENING(so))
4228 			SOLISTEN_UNLOCK_ASSERT(so);
4229 		else
4230 			SOCK_SENDBUF_UNLOCK_ASSERT(so);
4231 	}
4232 }
4233 
4234 /*
4235  * Create an external-format (``xsocket'') structure using the information in
4236  * the kernel-format socket structure pointed to by so.  This is done to
4237  * reduce the spew of irrelevant information over this interface, to isolate
4238  * user code from changes in the kernel structure, and potentially to provide
4239  * information-hiding if we decide that some of this information should be
4240  * hidden from users.
4241  */
4242 void
4243 sotoxsocket(struct socket *so, struct xsocket *xso)
4244 {
4245 
4246 	bzero(xso, sizeof(*xso));
4247 	xso->xso_len = sizeof *xso;
4248 	xso->xso_so = (uintptr_t)so;
4249 	xso->so_type = so->so_type;
4250 	xso->so_options = so->so_options;
4251 	xso->so_linger = so->so_linger;
4252 	xso->so_state = so->so_state;
4253 	xso->so_pcb = (uintptr_t)so->so_pcb;
4254 	xso->xso_protocol = so->so_proto->pr_protocol;
4255 	xso->xso_family = so->so_proto->pr_domain->dom_family;
4256 	xso->so_timeo = so->so_timeo;
4257 	xso->so_error = so->so_error;
4258 	xso->so_uid = so->so_cred->cr_uid;
4259 	xso->so_pgid = so->so_sigio ? so->so_sigio->sio_pgid : 0;
4260 	if (SOLISTENING(so)) {
4261 		xso->so_qlen = so->sol_qlen;
4262 		xso->so_incqlen = so->sol_incqlen;
4263 		xso->so_qlimit = so->sol_qlimit;
4264 		xso->so_oobmark = 0;
4265 	} else {
4266 		xso->so_state |= so->so_qstate;
4267 		xso->so_qlen = xso->so_incqlen = xso->so_qlimit = 0;
4268 		xso->so_oobmark = so->so_oobmark;
4269 		sbtoxsockbuf(&so->so_snd, &xso->so_snd);
4270 		sbtoxsockbuf(&so->so_rcv, &xso->so_rcv);
4271 	}
4272 }
4273 
4274 struct sockbuf *
4275 so_sockbuf_rcv(struct socket *so)
4276 {
4277 
4278 	return (&so->so_rcv);
4279 }
4280 
4281 struct sockbuf *
4282 so_sockbuf_snd(struct socket *so)
4283 {
4284 
4285 	return (&so->so_snd);
4286 }
4287 
4288 int
4289 so_state_get(const struct socket *so)
4290 {
4291 
4292 	return (so->so_state);
4293 }
4294 
4295 void
4296 so_state_set(struct socket *so, int val)
4297 {
4298 
4299 	so->so_state = val;
4300 }
4301 
4302 int
4303 so_options_get(const struct socket *so)
4304 {
4305 
4306 	return (so->so_options);
4307 }
4308 
4309 void
4310 so_options_set(struct socket *so, int val)
4311 {
4312 
4313 	so->so_options = val;
4314 }
4315 
4316 int
4317 so_error_get(const struct socket *so)
4318 {
4319 
4320 	return (so->so_error);
4321 }
4322 
4323 void
4324 so_error_set(struct socket *so, int val)
4325 {
4326 
4327 	so->so_error = val;
4328 }
4329 
4330 int
4331 so_linger_get(const struct socket *so)
4332 {
4333 
4334 	return (so->so_linger);
4335 }
4336 
4337 void
4338 so_linger_set(struct socket *so, int val)
4339 {
4340 
4341 	KASSERT(val >= 0 && val <= USHRT_MAX && val <= (INT_MAX / hz),
4342 	    ("%s: val %d out of range", __func__, val));
4343 
4344 	so->so_linger = val;
4345 }
4346 
4347 struct protosw *
4348 so_protosw_get(const struct socket *so)
4349 {
4350 
4351 	return (so->so_proto);
4352 }
4353 
4354 void
4355 so_protosw_set(struct socket *so, struct protosw *val)
4356 {
4357 
4358 	so->so_proto = val;
4359 }
4360 
4361 void
4362 so_sorwakeup(struct socket *so)
4363 {
4364 
4365 	sorwakeup(so);
4366 }
4367 
4368 void
4369 so_sowwakeup(struct socket *so)
4370 {
4371 
4372 	sowwakeup(so);
4373 }
4374 
4375 void
4376 so_sorwakeup_locked(struct socket *so)
4377 {
4378 
4379 	sorwakeup_locked(so);
4380 }
4381 
4382 void
4383 so_sowwakeup_locked(struct socket *so)
4384 {
4385 
4386 	sowwakeup_locked(so);
4387 }
4388 
4389 void
4390 so_lock(struct socket *so)
4391 {
4392 
4393 	SOCK_LOCK(so);
4394 }
4395 
4396 void
4397 so_unlock(struct socket *so)
4398 {
4399 
4400 	SOCK_UNLOCK(so);
4401 }
4402