xref: /freebsd/sys/kern/uipc_socket.c (revision 22cf89c938886d14f5796fc49f9f020c23ea8eaf)
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 			}
2433 			SBLASTRECORDCHK(&so->so_rcv);
2434 			SBLASTMBUFCHK(&so->so_rcv);
2435 			/*
2436 			 * We could receive some data while was notifying
2437 			 * the protocol. Skip blocking in this case.
2438 			 */
2439 			if (so->so_rcv.sb_mb == NULL) {
2440 				error = sbwait(so, SO_RCV);
2441 				if (error) {
2442 					SOCKBUF_UNLOCK(&so->so_rcv);
2443 					goto release;
2444 				}
2445 			}
2446 			m = so->so_rcv.sb_mb;
2447 			if (m != NULL)
2448 				nextrecord = m->m_nextpkt;
2449 		}
2450 	}
2451 
2452 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2453 	if (m != NULL && pr->pr_flags & PR_ATOMIC) {
2454 		if (report_real_len)
2455 			uio->uio_resid -= m_length(m, NULL) - moff;
2456 		flags |= MSG_TRUNC;
2457 		if ((flags & MSG_PEEK) == 0)
2458 			(void) sbdroprecord_locked(&so->so_rcv);
2459 	}
2460 	if ((flags & MSG_PEEK) == 0) {
2461 		if (m == NULL) {
2462 			/*
2463 			 * First part is an inline SB_EMPTY_FIXUP().  Second
2464 			 * part makes sure sb_lastrecord is up-to-date if
2465 			 * there is still data in the socket buffer.
2466 			 */
2467 			so->so_rcv.sb_mb = nextrecord;
2468 			if (so->so_rcv.sb_mb == NULL) {
2469 				so->so_rcv.sb_mbtail = NULL;
2470 				so->so_rcv.sb_lastrecord = NULL;
2471 			} else if (nextrecord->m_nextpkt == NULL)
2472 				so->so_rcv.sb_lastrecord = nextrecord;
2473 		}
2474 		SBLASTRECORDCHK(&so->so_rcv);
2475 		SBLASTMBUFCHK(&so->so_rcv);
2476 		/*
2477 		 * If soreceive() is being done from the socket callback,
2478 		 * then don't need to generate ACK to peer to update window,
2479 		 * since ACK will be generated on return to TCP.
2480 		 */
2481 		if (!(flags & MSG_SOCALLBCK) &&
2482 		    (pr->pr_flags & PR_WANTRCVD)) {
2483 			SOCKBUF_UNLOCK(&so->so_rcv);
2484 			VNET_SO_ASSERT(so);
2485 			pr->pr_rcvd(so, flags);
2486 			SOCKBUF_LOCK(&so->so_rcv);
2487 		}
2488 	}
2489 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2490 	if (orig_resid == uio->uio_resid && orig_resid &&
2491 	    (flags & MSG_EOR) == 0 && (so->so_rcv.sb_state & SBS_CANTRCVMORE) == 0) {
2492 		SOCKBUF_UNLOCK(&so->so_rcv);
2493 		goto restart;
2494 	}
2495 	SOCKBUF_UNLOCK(&so->so_rcv);
2496 
2497 	if (flagsp != NULL)
2498 		*flagsp |= flags;
2499 release:
2500 	SOCK_IO_RECV_UNLOCK(so);
2501 	return (error);
2502 }
2503 
2504 /*
2505  * Optimized version of soreceive() for stream (TCP) sockets.
2506  */
2507 int
2508 soreceive_stream(struct socket *so, struct sockaddr **psa, struct uio *uio,
2509     struct mbuf **mp0, struct mbuf **controlp, int *flagsp)
2510 {
2511 	int len = 0, error = 0, flags, oresid;
2512 	struct sockbuf *sb;
2513 	struct mbuf *m, *n = NULL;
2514 
2515 	/* We only do stream sockets. */
2516 	if (so->so_type != SOCK_STREAM)
2517 		return (EINVAL);
2518 	if (psa != NULL)
2519 		*psa = NULL;
2520 	if (flagsp != NULL)
2521 		flags = *flagsp &~ MSG_EOR;
2522 	else
2523 		flags = 0;
2524 	if (controlp != NULL)
2525 		*controlp = NULL;
2526 	if (flags & MSG_OOB)
2527 		return (soreceive_rcvoob(so, uio, flags));
2528 	if (mp0 != NULL)
2529 		*mp0 = NULL;
2530 
2531 	sb = &so->so_rcv;
2532 
2533 #ifdef KERN_TLS
2534 	/*
2535 	 * KTLS store TLS records as records with a control message to
2536 	 * describe the framing.
2537 	 *
2538 	 * We check once here before acquiring locks to optimize the
2539 	 * common case.
2540 	 */
2541 	if (sb->sb_tls_info != NULL)
2542 		return (soreceive_generic(so, psa, uio, mp0, controlp,
2543 		    flagsp));
2544 #endif
2545 
2546 	/* Prevent other readers from entering the socket. */
2547 	error = SOCK_IO_RECV_LOCK(so, SBLOCKWAIT(flags));
2548 	if (error)
2549 		return (error);
2550 	SOCKBUF_LOCK(sb);
2551 
2552 #ifdef KERN_TLS
2553 	if (sb->sb_tls_info != NULL) {
2554 		SOCKBUF_UNLOCK(sb);
2555 		SOCK_IO_RECV_UNLOCK(so);
2556 		return (soreceive_generic(so, psa, uio, mp0, controlp,
2557 		    flagsp));
2558 	}
2559 #endif
2560 
2561 	/* Easy one, no space to copyout anything. */
2562 	if (uio->uio_resid == 0) {
2563 		error = EINVAL;
2564 		goto out;
2565 	}
2566 	oresid = uio->uio_resid;
2567 
2568 	/* We will never ever get anything unless we are or were connected. */
2569 	if (!(so->so_state & (SS_ISCONNECTED|SS_ISDISCONNECTED))) {
2570 		error = ENOTCONN;
2571 		goto out;
2572 	}
2573 
2574 restart:
2575 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2576 
2577 	/* Abort if socket has reported problems. */
2578 	if (so->so_error) {
2579 		if (sbavail(sb) > 0)
2580 			goto deliver;
2581 		if (oresid > uio->uio_resid)
2582 			goto out;
2583 		error = so->so_error;
2584 		if (!(flags & MSG_PEEK))
2585 			so->so_error = 0;
2586 		goto out;
2587 	}
2588 
2589 	/* Door is closed.  Deliver what is left, if any. */
2590 	if (sb->sb_state & SBS_CANTRCVMORE) {
2591 		if (sbavail(sb) > 0)
2592 			goto deliver;
2593 		else
2594 			goto out;
2595 	}
2596 
2597 	/* Socket buffer is empty and we shall not block. */
2598 	if (sbavail(sb) == 0 &&
2599 	    ((so->so_state & SS_NBIO) || (flags & (MSG_DONTWAIT|MSG_NBIO)))) {
2600 		error = EAGAIN;
2601 		goto out;
2602 	}
2603 
2604 	/* Socket buffer got some data that we shall deliver now. */
2605 	if (sbavail(sb) > 0 && !(flags & MSG_WAITALL) &&
2606 	    ((so->so_state & SS_NBIO) ||
2607 	     (flags & (MSG_DONTWAIT|MSG_NBIO)) ||
2608 	     sbavail(sb) >= sb->sb_lowat ||
2609 	     sbavail(sb) >= uio->uio_resid ||
2610 	     sbavail(sb) >= sb->sb_hiwat) ) {
2611 		goto deliver;
2612 	}
2613 
2614 	/* On MSG_WAITALL we must wait until all data or error arrives. */
2615 	if ((flags & MSG_WAITALL) &&
2616 	    (sbavail(sb) >= uio->uio_resid || sbavail(sb) >= sb->sb_hiwat))
2617 		goto deliver;
2618 
2619 	/*
2620 	 * Wait and block until (more) data comes in.
2621 	 * NB: Drops the sockbuf lock during wait.
2622 	 */
2623 	error = sbwait(so, SO_RCV);
2624 	if (error)
2625 		goto out;
2626 	goto restart;
2627 
2628 deliver:
2629 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2630 	KASSERT(sbavail(sb) > 0, ("%s: sockbuf empty", __func__));
2631 	KASSERT(sb->sb_mb != NULL, ("%s: sb_mb == NULL", __func__));
2632 
2633 	/* Statistics. */
2634 	if (uio->uio_td)
2635 		uio->uio_td->td_ru.ru_msgrcv++;
2636 
2637 	/* Fill uio until full or current end of socket buffer is reached. */
2638 	len = min(uio->uio_resid, sbavail(sb));
2639 	if (mp0 != NULL) {
2640 		/* Dequeue as many mbufs as possible. */
2641 		if (!(flags & MSG_PEEK) && len >= sb->sb_mb->m_len) {
2642 			if (*mp0 == NULL)
2643 				*mp0 = sb->sb_mb;
2644 			else
2645 				m_cat(*mp0, sb->sb_mb);
2646 			for (m = sb->sb_mb;
2647 			     m != NULL && m->m_len <= len;
2648 			     m = m->m_next) {
2649 				KASSERT(!(m->m_flags & M_NOTAVAIL),
2650 				    ("%s: m %p not available", __func__, m));
2651 				len -= m->m_len;
2652 				uio->uio_resid -= m->m_len;
2653 				sbfree(sb, m);
2654 				n = m;
2655 			}
2656 			n->m_next = NULL;
2657 			sb->sb_mb = m;
2658 			sb->sb_lastrecord = sb->sb_mb;
2659 			if (sb->sb_mb == NULL)
2660 				SB_EMPTY_FIXUP(sb);
2661 		}
2662 		/* Copy the remainder. */
2663 		if (len > 0) {
2664 			KASSERT(sb->sb_mb != NULL,
2665 			    ("%s: len > 0 && sb->sb_mb empty", __func__));
2666 
2667 			m = m_copym(sb->sb_mb, 0, len, M_NOWAIT);
2668 			if (m == NULL)
2669 				len = 0;	/* Don't flush data from sockbuf. */
2670 			else
2671 				uio->uio_resid -= len;
2672 			if (*mp0 != NULL)
2673 				m_cat(*mp0, m);
2674 			else
2675 				*mp0 = m;
2676 			if (*mp0 == NULL) {
2677 				error = ENOBUFS;
2678 				goto out;
2679 			}
2680 		}
2681 	} else {
2682 		/* NB: Must unlock socket buffer as uiomove may sleep. */
2683 		SOCKBUF_UNLOCK(sb);
2684 		error = m_mbuftouio(uio, sb->sb_mb, len);
2685 		SOCKBUF_LOCK(sb);
2686 		if (error)
2687 			goto out;
2688 	}
2689 	SBLASTRECORDCHK(sb);
2690 	SBLASTMBUFCHK(sb);
2691 
2692 	/*
2693 	 * Remove the delivered data from the socket buffer unless we
2694 	 * were only peeking.
2695 	 */
2696 	if (!(flags & MSG_PEEK)) {
2697 		if (len > 0)
2698 			sbdrop_locked(sb, len);
2699 
2700 		/* Notify protocol that we drained some data. */
2701 		if ((so->so_proto->pr_flags & PR_WANTRCVD) &&
2702 		    (((flags & MSG_WAITALL) && uio->uio_resid > 0) ||
2703 		     !(flags & MSG_SOCALLBCK))) {
2704 			SOCKBUF_UNLOCK(sb);
2705 			VNET_SO_ASSERT(so);
2706 			so->so_proto->pr_rcvd(so, flags);
2707 			SOCKBUF_LOCK(sb);
2708 		}
2709 	}
2710 
2711 	/*
2712 	 * For MSG_WAITALL we may have to loop again and wait for
2713 	 * more data to come in.
2714 	 */
2715 	if ((flags & MSG_WAITALL) && uio->uio_resid > 0)
2716 		goto restart;
2717 out:
2718 	SBLASTRECORDCHK(sb);
2719 	SBLASTMBUFCHK(sb);
2720 	SOCKBUF_UNLOCK(sb);
2721 	SOCK_IO_RECV_UNLOCK(so);
2722 	return (error);
2723 }
2724 
2725 /*
2726  * Optimized version of soreceive() for simple datagram cases from userspace.
2727  * Unlike in the stream case, we're able to drop a datagram if copyout()
2728  * fails, and because we handle datagrams atomically, we don't need to use a
2729  * sleep lock to prevent I/O interlacing.
2730  */
2731 int
2732 soreceive_dgram(struct socket *so, struct sockaddr **psa, struct uio *uio,
2733     struct mbuf **mp0, struct mbuf **controlp, int *flagsp)
2734 {
2735 	struct mbuf *m, *m2;
2736 	int flags, error;
2737 	ssize_t len;
2738 	struct protosw *pr = so->so_proto;
2739 	struct mbuf *nextrecord;
2740 
2741 	if (psa != NULL)
2742 		*psa = NULL;
2743 	if (controlp != NULL)
2744 		*controlp = NULL;
2745 	if (flagsp != NULL)
2746 		flags = *flagsp &~ MSG_EOR;
2747 	else
2748 		flags = 0;
2749 
2750 	/*
2751 	 * For any complicated cases, fall back to the full
2752 	 * soreceive_generic().
2753 	 */
2754 	if (mp0 != NULL || (flags & (MSG_PEEK | MSG_OOB | MSG_TRUNC)))
2755 		return (soreceive_generic(so, psa, uio, mp0, controlp,
2756 		    flagsp));
2757 
2758 	/*
2759 	 * Enforce restrictions on use.
2760 	 */
2761 	KASSERT((pr->pr_flags & PR_WANTRCVD) == 0,
2762 	    ("soreceive_dgram: wantrcvd"));
2763 	KASSERT(pr->pr_flags & PR_ATOMIC, ("soreceive_dgram: !atomic"));
2764 	KASSERT((so->so_rcv.sb_state & SBS_RCVATMARK) == 0,
2765 	    ("soreceive_dgram: SBS_RCVATMARK"));
2766 	KASSERT((so->so_proto->pr_flags & PR_CONNREQUIRED) == 0,
2767 	    ("soreceive_dgram: P_CONNREQUIRED"));
2768 
2769 	/*
2770 	 * Loop blocking while waiting for a datagram.
2771 	 */
2772 	SOCKBUF_LOCK(&so->so_rcv);
2773 	while ((m = so->so_rcv.sb_mb) == NULL) {
2774 		KASSERT(sbavail(&so->so_rcv) == 0,
2775 		    ("soreceive_dgram: sb_mb NULL but sbavail %u",
2776 		    sbavail(&so->so_rcv)));
2777 		if (so->so_error) {
2778 			error = so->so_error;
2779 			so->so_error = 0;
2780 			SOCKBUF_UNLOCK(&so->so_rcv);
2781 			return (error);
2782 		}
2783 		if (so->so_rcv.sb_state & SBS_CANTRCVMORE ||
2784 		    uio->uio_resid == 0) {
2785 			SOCKBUF_UNLOCK(&so->so_rcv);
2786 			return (0);
2787 		}
2788 		if ((so->so_state & SS_NBIO) ||
2789 		    (flags & (MSG_DONTWAIT|MSG_NBIO))) {
2790 			SOCKBUF_UNLOCK(&so->so_rcv);
2791 			return (EWOULDBLOCK);
2792 		}
2793 		SBLASTRECORDCHK(&so->so_rcv);
2794 		SBLASTMBUFCHK(&so->so_rcv);
2795 		error = sbwait(so, SO_RCV);
2796 		if (error) {
2797 			SOCKBUF_UNLOCK(&so->so_rcv);
2798 			return (error);
2799 		}
2800 	}
2801 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2802 
2803 	if (uio->uio_td)
2804 		uio->uio_td->td_ru.ru_msgrcv++;
2805 	SBLASTRECORDCHK(&so->so_rcv);
2806 	SBLASTMBUFCHK(&so->so_rcv);
2807 	nextrecord = m->m_nextpkt;
2808 	if (nextrecord == NULL) {
2809 		KASSERT(so->so_rcv.sb_lastrecord == m,
2810 		    ("soreceive_dgram: lastrecord != m"));
2811 	}
2812 
2813 	KASSERT(so->so_rcv.sb_mb->m_nextpkt == nextrecord,
2814 	    ("soreceive_dgram: m_nextpkt != nextrecord"));
2815 
2816 	/*
2817 	 * Pull 'm' and its chain off the front of the packet queue.
2818 	 */
2819 	so->so_rcv.sb_mb = NULL;
2820 	sockbuf_pushsync(&so->so_rcv, nextrecord);
2821 
2822 	/*
2823 	 * Walk 'm's chain and free that many bytes from the socket buffer.
2824 	 */
2825 	for (m2 = m; m2 != NULL; m2 = m2->m_next)
2826 		sbfree(&so->so_rcv, m2);
2827 
2828 	/*
2829 	 * Do a few last checks before we let go of the lock.
2830 	 */
2831 	SBLASTRECORDCHK(&so->so_rcv);
2832 	SBLASTMBUFCHK(&so->so_rcv);
2833 	SOCKBUF_UNLOCK(&so->so_rcv);
2834 
2835 	if (pr->pr_flags & PR_ADDR) {
2836 		KASSERT(m->m_type == MT_SONAME,
2837 		    ("m->m_type == %d", m->m_type));
2838 		if (psa != NULL)
2839 			*psa = sodupsockaddr(mtod(m, struct sockaddr *),
2840 			    M_NOWAIT);
2841 		m = m_free(m);
2842 	}
2843 	if (m == NULL) {
2844 		/* XXXRW: Can this happen? */
2845 		return (0);
2846 	}
2847 
2848 	/*
2849 	 * Packet to copyout() is now in 'm' and it is disconnected from the
2850 	 * queue.
2851 	 *
2852 	 * Process one or more MT_CONTROL mbufs present before any data mbufs
2853 	 * in the first mbuf chain on the socket buffer.  We call into the
2854 	 * protocol to perform externalization (or freeing if controlp ==
2855 	 * NULL). In some cases there can be only MT_CONTROL mbufs without
2856 	 * MT_DATA mbufs.
2857 	 */
2858 	if (m->m_type == MT_CONTROL) {
2859 		struct mbuf *cm = NULL, *cmn;
2860 		struct mbuf **cme = &cm;
2861 
2862 		do {
2863 			m2 = m->m_next;
2864 			m->m_next = NULL;
2865 			*cme = m;
2866 			cme = &(*cme)->m_next;
2867 			m = m2;
2868 		} while (m != NULL && m->m_type == MT_CONTROL);
2869 		while (cm != NULL) {
2870 			cmn = cm->m_next;
2871 			cm->m_next = NULL;
2872 			if (pr->pr_domain->dom_externalize != NULL) {
2873 				error = (*pr->pr_domain->dom_externalize)
2874 				    (cm, controlp, flags);
2875 			} else if (controlp != NULL)
2876 				*controlp = cm;
2877 			else
2878 				m_freem(cm);
2879 			if (controlp != NULL) {
2880 				while (*controlp != NULL)
2881 					controlp = &(*controlp)->m_next;
2882 			}
2883 			cm = cmn;
2884 		}
2885 	}
2886 	KASSERT(m == NULL || m->m_type == MT_DATA,
2887 	    ("soreceive_dgram: !data"));
2888 	while (m != NULL && uio->uio_resid > 0) {
2889 		len = uio->uio_resid;
2890 		if (len > m->m_len)
2891 			len = m->m_len;
2892 		error = uiomove(mtod(m, char *), (int)len, uio);
2893 		if (error) {
2894 			m_freem(m);
2895 			return (error);
2896 		}
2897 		if (len == m->m_len)
2898 			m = m_free(m);
2899 		else {
2900 			m->m_data += len;
2901 			m->m_len -= len;
2902 		}
2903 	}
2904 	if (m != NULL) {
2905 		flags |= MSG_TRUNC;
2906 		m_freem(m);
2907 	}
2908 	if (flagsp != NULL)
2909 		*flagsp |= flags;
2910 	return (0);
2911 }
2912 
2913 int
2914 soreceive(struct socket *so, struct sockaddr **psa, struct uio *uio,
2915     struct mbuf **mp0, struct mbuf **controlp, int *flagsp)
2916 {
2917 	int error;
2918 
2919 	CURVNET_SET(so->so_vnet);
2920 	error = so->so_proto->pr_soreceive(so, psa, uio, mp0, controlp, flagsp);
2921 	CURVNET_RESTORE();
2922 	return (error);
2923 }
2924 
2925 int
2926 soshutdown(struct socket *so, int how)
2927 {
2928 	struct protosw *pr;
2929 	int error, soerror_enotconn;
2930 
2931 	if (!(how == SHUT_RD || how == SHUT_WR || how == SHUT_RDWR))
2932 		return (EINVAL);
2933 
2934 	soerror_enotconn = 0;
2935 	SOCK_LOCK(so);
2936 	if ((so->so_state &
2937 	    (SS_ISCONNECTED | SS_ISCONNECTING | SS_ISDISCONNECTING)) == 0) {
2938 		/*
2939 		 * POSIX mandates us to return ENOTCONN when shutdown(2) is
2940 		 * invoked on a datagram sockets, however historically we would
2941 		 * actually tear socket down. This is known to be leveraged by
2942 		 * some applications to unblock process waiting in recvXXX(2)
2943 		 * by other process that it shares that socket with. Try to meet
2944 		 * both backward-compatibility and POSIX requirements by forcing
2945 		 * ENOTCONN but still asking protocol to perform pru_shutdown().
2946 		 */
2947 		if (so->so_type != SOCK_DGRAM && !SOLISTENING(so)) {
2948 			SOCK_UNLOCK(so);
2949 			return (ENOTCONN);
2950 		}
2951 		soerror_enotconn = 1;
2952 	}
2953 
2954 	if (SOLISTENING(so)) {
2955 		if (how != SHUT_WR) {
2956 			so->so_error = ECONNABORTED;
2957 			solisten_wakeup(so);	/* unlocks so */
2958 		} else {
2959 			SOCK_UNLOCK(so);
2960 		}
2961 		goto done;
2962 	}
2963 	SOCK_UNLOCK(so);
2964 
2965 	CURVNET_SET(so->so_vnet);
2966 	pr = so->so_proto;
2967 	if (pr->pr_flush != NULL)
2968 		pr->pr_flush(so, how);
2969 	if (how != SHUT_WR)
2970 		sorflush(so);
2971 	if (how != SHUT_RD) {
2972 		error = pr->pr_shutdown(so);
2973 		wakeup(&so->so_timeo);
2974 		CURVNET_RESTORE();
2975 		return ((error == 0 && soerror_enotconn) ? ENOTCONN : error);
2976 	}
2977 	wakeup(&so->so_timeo);
2978 	CURVNET_RESTORE();
2979 
2980 done:
2981 	return (soerror_enotconn ? ENOTCONN : 0);
2982 }
2983 
2984 void
2985 sorflush(struct socket *so)
2986 {
2987 	struct protosw *pr;
2988 	int error;
2989 
2990 	VNET_SO_ASSERT(so);
2991 
2992 	/*
2993 	 * Dislodge threads currently blocked in receive and wait to acquire
2994 	 * a lock against other simultaneous readers before clearing the
2995 	 * socket buffer.  Don't let our acquire be interrupted by a signal
2996 	 * despite any existing socket disposition on interruptable waiting.
2997 	 */
2998 	socantrcvmore(so);
2999 
3000 	error = SOCK_IO_RECV_LOCK(so, SBL_WAIT | SBL_NOINTR);
3001 	if (error != 0) {
3002 		KASSERT(SOLISTENING(so),
3003 		    ("%s: soiolock(%p) failed", __func__, so));
3004 		return;
3005 	}
3006 
3007 	pr = so->so_proto;
3008 	if (pr->pr_flags & PR_RIGHTS) {
3009 		MPASS(pr->pr_domain->dom_dispose != NULL);
3010 		(*pr->pr_domain->dom_dispose)(so);
3011 	} else {
3012 		sbrelease(so, SO_RCV);
3013 		SOCK_IO_RECV_UNLOCK(so);
3014 	}
3015 
3016 }
3017 
3018 /*
3019  * Wrapper for Socket established helper hook.
3020  * Parameters: socket, context of the hook point, hook id.
3021  */
3022 static int inline
3023 hhook_run_socket(struct socket *so, void *hctx, int32_t h_id)
3024 {
3025 	struct socket_hhook_data hhook_data = {
3026 		.so = so,
3027 		.hctx = hctx,
3028 		.m = NULL,
3029 		.status = 0
3030 	};
3031 
3032 	CURVNET_SET(so->so_vnet);
3033 	HHOOKS_RUN_IF(V_socket_hhh[h_id], &hhook_data, &so->osd);
3034 	CURVNET_RESTORE();
3035 
3036 	/* Ugly but needed, since hhooks return void for now */
3037 	return (hhook_data.status);
3038 }
3039 
3040 /*
3041  * Perhaps this routine, and sooptcopyout(), below, ought to come in an
3042  * additional variant to handle the case where the option value needs to be
3043  * some kind of integer, but not a specific size.  In addition to their use
3044  * here, these functions are also called by the protocol-level pr_ctloutput()
3045  * routines.
3046  */
3047 int
3048 sooptcopyin(struct sockopt *sopt, void *buf, size_t len, size_t minlen)
3049 {
3050 	size_t	valsize;
3051 
3052 	/*
3053 	 * If the user gives us more than we wanted, we ignore it, but if we
3054 	 * don't get the minimum length the caller wants, we return EINVAL.
3055 	 * On success, sopt->sopt_valsize is set to however much we actually
3056 	 * retrieved.
3057 	 */
3058 	if ((valsize = sopt->sopt_valsize) < minlen)
3059 		return EINVAL;
3060 	if (valsize > len)
3061 		sopt->sopt_valsize = valsize = len;
3062 
3063 	if (sopt->sopt_td != NULL)
3064 		return (copyin(sopt->sopt_val, buf, valsize));
3065 
3066 	bcopy(sopt->sopt_val, buf, valsize);
3067 	return (0);
3068 }
3069 
3070 /*
3071  * Kernel version of setsockopt(2).
3072  *
3073  * XXX: optlen is size_t, not socklen_t
3074  */
3075 int
3076 so_setsockopt(struct socket *so, int level, int optname, void *optval,
3077     size_t optlen)
3078 {
3079 	struct sockopt sopt;
3080 
3081 	sopt.sopt_level = level;
3082 	sopt.sopt_name = optname;
3083 	sopt.sopt_dir = SOPT_SET;
3084 	sopt.sopt_val = optval;
3085 	sopt.sopt_valsize = optlen;
3086 	sopt.sopt_td = NULL;
3087 	return (sosetopt(so, &sopt));
3088 }
3089 
3090 int
3091 sosetopt(struct socket *so, struct sockopt *sopt)
3092 {
3093 	int	error, optval;
3094 	struct	linger l;
3095 	struct	timeval tv;
3096 	sbintime_t val, *valp;
3097 	uint32_t val32;
3098 #ifdef MAC
3099 	struct mac extmac;
3100 #endif
3101 
3102 	CURVNET_SET(so->so_vnet);
3103 	error = 0;
3104 	if (sopt->sopt_level != SOL_SOCKET) {
3105 		if (so->so_proto->pr_ctloutput != NULL)
3106 			error = (*so->so_proto->pr_ctloutput)(so, sopt);
3107 		else
3108 			error = ENOPROTOOPT;
3109 	} else {
3110 		switch (sopt->sopt_name) {
3111 		case SO_ACCEPTFILTER:
3112 			error = accept_filt_setopt(so, sopt);
3113 			if (error)
3114 				goto bad;
3115 			break;
3116 
3117 		case SO_LINGER:
3118 			error = sooptcopyin(sopt, &l, sizeof l, sizeof l);
3119 			if (error)
3120 				goto bad;
3121 			if (l.l_linger < 0 ||
3122 			    l.l_linger > USHRT_MAX ||
3123 			    l.l_linger > (INT_MAX / hz)) {
3124 				error = EDOM;
3125 				goto bad;
3126 			}
3127 			SOCK_LOCK(so);
3128 			so->so_linger = l.l_linger;
3129 			if (l.l_onoff)
3130 				so->so_options |= SO_LINGER;
3131 			else
3132 				so->so_options &= ~SO_LINGER;
3133 			SOCK_UNLOCK(so);
3134 			break;
3135 
3136 		case SO_DEBUG:
3137 		case SO_KEEPALIVE:
3138 		case SO_DONTROUTE:
3139 		case SO_USELOOPBACK:
3140 		case SO_BROADCAST:
3141 		case SO_REUSEADDR:
3142 		case SO_REUSEPORT:
3143 		case SO_REUSEPORT_LB:
3144 		case SO_OOBINLINE:
3145 		case SO_TIMESTAMP:
3146 		case SO_BINTIME:
3147 		case SO_NOSIGPIPE:
3148 		case SO_NO_DDP:
3149 		case SO_NO_OFFLOAD:
3150 		case SO_RERROR:
3151 			error = sooptcopyin(sopt, &optval, sizeof optval,
3152 			    sizeof optval);
3153 			if (error)
3154 				goto bad;
3155 			SOCK_LOCK(so);
3156 			if (optval)
3157 				so->so_options |= sopt->sopt_name;
3158 			else
3159 				so->so_options &= ~sopt->sopt_name;
3160 			SOCK_UNLOCK(so);
3161 			break;
3162 
3163 		case SO_SETFIB:
3164 			error = sooptcopyin(sopt, &optval, sizeof optval,
3165 			    sizeof optval);
3166 			if (error)
3167 				goto bad;
3168 
3169 			if (optval < 0 || optval >= rt_numfibs) {
3170 				error = EINVAL;
3171 				goto bad;
3172 			}
3173 			if (((so->so_proto->pr_domain->dom_family == PF_INET) ||
3174 			   (so->so_proto->pr_domain->dom_family == PF_INET6) ||
3175 			   (so->so_proto->pr_domain->dom_family == PF_ROUTE)))
3176 				so->so_fibnum = optval;
3177 			else
3178 				so->so_fibnum = 0;
3179 			break;
3180 
3181 		case SO_USER_COOKIE:
3182 			error = sooptcopyin(sopt, &val32, sizeof val32,
3183 			    sizeof val32);
3184 			if (error)
3185 				goto bad;
3186 			so->so_user_cookie = val32;
3187 			break;
3188 
3189 		case SO_SNDBUF:
3190 		case SO_RCVBUF:
3191 		case SO_SNDLOWAT:
3192 		case SO_RCVLOWAT:
3193 			error = so->so_proto->pr_setsbopt(so, sopt);
3194 			if (error)
3195 				goto bad;
3196 			break;
3197 
3198 		case SO_SNDTIMEO:
3199 		case SO_RCVTIMEO:
3200 #ifdef COMPAT_FREEBSD32
3201 			if (SV_CURPROC_FLAG(SV_ILP32)) {
3202 				struct timeval32 tv32;
3203 
3204 				error = sooptcopyin(sopt, &tv32, sizeof tv32,
3205 				    sizeof tv32);
3206 				CP(tv32, tv, tv_sec);
3207 				CP(tv32, tv, tv_usec);
3208 			} else
3209 #endif
3210 				error = sooptcopyin(sopt, &tv, sizeof tv,
3211 				    sizeof tv);
3212 			if (error)
3213 				goto bad;
3214 			if (tv.tv_sec < 0 || tv.tv_usec < 0 ||
3215 			    tv.tv_usec >= 1000000) {
3216 				error = EDOM;
3217 				goto bad;
3218 			}
3219 			if (tv.tv_sec > INT32_MAX)
3220 				val = SBT_MAX;
3221 			else
3222 				val = tvtosbt(tv);
3223 			SOCK_LOCK(so);
3224 			valp = sopt->sopt_name == SO_SNDTIMEO ?
3225 			    (SOLISTENING(so) ? &so->sol_sbsnd_timeo :
3226 			    &so->so_snd.sb_timeo) :
3227 			    (SOLISTENING(so) ? &so->sol_sbrcv_timeo :
3228 			    &so->so_rcv.sb_timeo);
3229 			*valp = val;
3230 			SOCK_UNLOCK(so);
3231 			break;
3232 
3233 		case SO_LABEL:
3234 #ifdef MAC
3235 			error = sooptcopyin(sopt, &extmac, sizeof extmac,
3236 			    sizeof extmac);
3237 			if (error)
3238 				goto bad;
3239 			error = mac_setsockopt_label(sopt->sopt_td->td_ucred,
3240 			    so, &extmac);
3241 #else
3242 			error = EOPNOTSUPP;
3243 #endif
3244 			break;
3245 
3246 		case SO_TS_CLOCK:
3247 			error = sooptcopyin(sopt, &optval, sizeof optval,
3248 			    sizeof optval);
3249 			if (error)
3250 				goto bad;
3251 			if (optval < 0 || optval > SO_TS_CLOCK_MAX) {
3252 				error = EINVAL;
3253 				goto bad;
3254 			}
3255 			so->so_ts_clock = optval;
3256 			break;
3257 
3258 		case SO_MAX_PACING_RATE:
3259 			error = sooptcopyin(sopt, &val32, sizeof(val32),
3260 			    sizeof(val32));
3261 			if (error)
3262 				goto bad;
3263 			so->so_max_pacing_rate = val32;
3264 			break;
3265 
3266 		default:
3267 			if (V_socket_hhh[HHOOK_SOCKET_OPT]->hhh_nhooks > 0)
3268 				error = hhook_run_socket(so, sopt,
3269 				    HHOOK_SOCKET_OPT);
3270 			else
3271 				error = ENOPROTOOPT;
3272 			break;
3273 		}
3274 		if (error == 0 && so->so_proto->pr_ctloutput != NULL)
3275 			(void)(*so->so_proto->pr_ctloutput)(so, sopt);
3276 	}
3277 bad:
3278 	CURVNET_RESTORE();
3279 	return (error);
3280 }
3281 
3282 /*
3283  * Helper routine for getsockopt.
3284  */
3285 int
3286 sooptcopyout(struct sockopt *sopt, const void *buf, size_t len)
3287 {
3288 	int	error;
3289 	size_t	valsize;
3290 
3291 	error = 0;
3292 
3293 	/*
3294 	 * Documented get behavior is that we always return a value, possibly
3295 	 * truncated to fit in the user's buffer.  Traditional behavior is
3296 	 * that we always tell the user precisely how much we copied, rather
3297 	 * than something useful like the total amount we had available for
3298 	 * her.  Note that this interface is not idempotent; the entire
3299 	 * answer must be generated ahead of time.
3300 	 */
3301 	valsize = min(len, sopt->sopt_valsize);
3302 	sopt->sopt_valsize = valsize;
3303 	if (sopt->sopt_val != NULL) {
3304 		if (sopt->sopt_td != NULL)
3305 			error = copyout(buf, sopt->sopt_val, valsize);
3306 		else
3307 			bcopy(buf, sopt->sopt_val, valsize);
3308 	}
3309 	return (error);
3310 }
3311 
3312 int
3313 sogetopt(struct socket *so, struct sockopt *sopt)
3314 {
3315 	int	error, optval;
3316 	struct	linger l;
3317 	struct	timeval tv;
3318 #ifdef MAC
3319 	struct mac extmac;
3320 #endif
3321 
3322 	CURVNET_SET(so->so_vnet);
3323 	error = 0;
3324 	if (sopt->sopt_level != SOL_SOCKET) {
3325 		if (so->so_proto->pr_ctloutput != NULL)
3326 			error = (*so->so_proto->pr_ctloutput)(so, sopt);
3327 		else
3328 			error = ENOPROTOOPT;
3329 		CURVNET_RESTORE();
3330 		return (error);
3331 	} else {
3332 		switch (sopt->sopt_name) {
3333 		case SO_ACCEPTFILTER:
3334 			error = accept_filt_getopt(so, sopt);
3335 			break;
3336 
3337 		case SO_LINGER:
3338 			SOCK_LOCK(so);
3339 			l.l_onoff = so->so_options & SO_LINGER;
3340 			l.l_linger = so->so_linger;
3341 			SOCK_UNLOCK(so);
3342 			error = sooptcopyout(sopt, &l, sizeof l);
3343 			break;
3344 
3345 		case SO_USELOOPBACK:
3346 		case SO_DONTROUTE:
3347 		case SO_DEBUG:
3348 		case SO_KEEPALIVE:
3349 		case SO_REUSEADDR:
3350 		case SO_REUSEPORT:
3351 		case SO_REUSEPORT_LB:
3352 		case SO_BROADCAST:
3353 		case SO_OOBINLINE:
3354 		case SO_ACCEPTCONN:
3355 		case SO_TIMESTAMP:
3356 		case SO_BINTIME:
3357 		case SO_NOSIGPIPE:
3358 		case SO_NO_DDP:
3359 		case SO_NO_OFFLOAD:
3360 		case SO_RERROR:
3361 			optval = so->so_options & sopt->sopt_name;
3362 integer:
3363 			error = sooptcopyout(sopt, &optval, sizeof optval);
3364 			break;
3365 
3366 		case SO_DOMAIN:
3367 			optval = so->so_proto->pr_domain->dom_family;
3368 			goto integer;
3369 
3370 		case SO_TYPE:
3371 			optval = so->so_type;
3372 			goto integer;
3373 
3374 		case SO_PROTOCOL:
3375 			optval = so->so_proto->pr_protocol;
3376 			goto integer;
3377 
3378 		case SO_ERROR:
3379 			SOCK_LOCK(so);
3380 			if (so->so_error) {
3381 				optval = so->so_error;
3382 				so->so_error = 0;
3383 			} else {
3384 				optval = so->so_rerror;
3385 				so->so_rerror = 0;
3386 			}
3387 			SOCK_UNLOCK(so);
3388 			goto integer;
3389 
3390 		case SO_SNDBUF:
3391 			optval = SOLISTENING(so) ? so->sol_sbsnd_hiwat :
3392 			    so->so_snd.sb_hiwat;
3393 			goto integer;
3394 
3395 		case SO_RCVBUF:
3396 			optval = SOLISTENING(so) ? so->sol_sbrcv_hiwat :
3397 			    so->so_rcv.sb_hiwat;
3398 			goto integer;
3399 
3400 		case SO_SNDLOWAT:
3401 			optval = SOLISTENING(so) ? so->sol_sbsnd_lowat :
3402 			    so->so_snd.sb_lowat;
3403 			goto integer;
3404 
3405 		case SO_RCVLOWAT:
3406 			optval = SOLISTENING(so) ? so->sol_sbrcv_lowat :
3407 			    so->so_rcv.sb_lowat;
3408 			goto integer;
3409 
3410 		case SO_SNDTIMEO:
3411 		case SO_RCVTIMEO:
3412 			SOCK_LOCK(so);
3413 			tv = sbttotv(sopt->sopt_name == SO_SNDTIMEO ?
3414 			    (SOLISTENING(so) ? so->sol_sbsnd_timeo :
3415 			    so->so_snd.sb_timeo) :
3416 			    (SOLISTENING(so) ? so->sol_sbrcv_timeo :
3417 			    so->so_rcv.sb_timeo));
3418 			SOCK_UNLOCK(so);
3419 #ifdef COMPAT_FREEBSD32
3420 			if (SV_CURPROC_FLAG(SV_ILP32)) {
3421 				struct timeval32 tv32;
3422 
3423 				CP(tv, tv32, tv_sec);
3424 				CP(tv, tv32, tv_usec);
3425 				error = sooptcopyout(sopt, &tv32, sizeof tv32);
3426 			} else
3427 #endif
3428 				error = sooptcopyout(sopt, &tv, sizeof tv);
3429 			break;
3430 
3431 		case SO_LABEL:
3432 #ifdef MAC
3433 			error = sooptcopyin(sopt, &extmac, sizeof(extmac),
3434 			    sizeof(extmac));
3435 			if (error)
3436 				goto bad;
3437 			error = mac_getsockopt_label(sopt->sopt_td->td_ucred,
3438 			    so, &extmac);
3439 			if (error)
3440 				goto bad;
3441 			error = sooptcopyout(sopt, &extmac, sizeof extmac);
3442 #else
3443 			error = EOPNOTSUPP;
3444 #endif
3445 			break;
3446 
3447 		case SO_PEERLABEL:
3448 #ifdef MAC
3449 			error = sooptcopyin(sopt, &extmac, sizeof(extmac),
3450 			    sizeof(extmac));
3451 			if (error)
3452 				goto bad;
3453 			error = mac_getsockopt_peerlabel(
3454 			    sopt->sopt_td->td_ucred, so, &extmac);
3455 			if (error)
3456 				goto bad;
3457 			error = sooptcopyout(sopt, &extmac, sizeof extmac);
3458 #else
3459 			error = EOPNOTSUPP;
3460 #endif
3461 			break;
3462 
3463 		case SO_LISTENQLIMIT:
3464 			optval = SOLISTENING(so) ? so->sol_qlimit : 0;
3465 			goto integer;
3466 
3467 		case SO_LISTENQLEN:
3468 			optval = SOLISTENING(so) ? so->sol_qlen : 0;
3469 			goto integer;
3470 
3471 		case SO_LISTENINCQLEN:
3472 			optval = SOLISTENING(so) ? so->sol_incqlen : 0;
3473 			goto integer;
3474 
3475 		case SO_TS_CLOCK:
3476 			optval = so->so_ts_clock;
3477 			goto integer;
3478 
3479 		case SO_MAX_PACING_RATE:
3480 			optval = so->so_max_pacing_rate;
3481 			goto integer;
3482 
3483 		default:
3484 			if (V_socket_hhh[HHOOK_SOCKET_OPT]->hhh_nhooks > 0)
3485 				error = hhook_run_socket(so, sopt,
3486 				    HHOOK_SOCKET_OPT);
3487 			else
3488 				error = ENOPROTOOPT;
3489 			break;
3490 		}
3491 	}
3492 #ifdef MAC
3493 bad:
3494 #endif
3495 	CURVNET_RESTORE();
3496 	return (error);
3497 }
3498 
3499 int
3500 soopt_getm(struct sockopt *sopt, struct mbuf **mp)
3501 {
3502 	struct mbuf *m, *m_prev;
3503 	int sopt_size = sopt->sopt_valsize;
3504 
3505 	MGET(m, sopt->sopt_td ? M_WAITOK : M_NOWAIT, MT_DATA);
3506 	if (m == NULL)
3507 		return ENOBUFS;
3508 	if (sopt_size > MLEN) {
3509 		MCLGET(m, sopt->sopt_td ? M_WAITOK : M_NOWAIT);
3510 		if ((m->m_flags & M_EXT) == 0) {
3511 			m_free(m);
3512 			return ENOBUFS;
3513 		}
3514 		m->m_len = min(MCLBYTES, sopt_size);
3515 	} else {
3516 		m->m_len = min(MLEN, sopt_size);
3517 	}
3518 	sopt_size -= m->m_len;
3519 	*mp = m;
3520 	m_prev = m;
3521 
3522 	while (sopt_size) {
3523 		MGET(m, sopt->sopt_td ? M_WAITOK : M_NOWAIT, MT_DATA);
3524 		if (m == NULL) {
3525 			m_freem(*mp);
3526 			return ENOBUFS;
3527 		}
3528 		if (sopt_size > MLEN) {
3529 			MCLGET(m, sopt->sopt_td != NULL ? M_WAITOK :
3530 			    M_NOWAIT);
3531 			if ((m->m_flags & M_EXT) == 0) {
3532 				m_freem(m);
3533 				m_freem(*mp);
3534 				return ENOBUFS;
3535 			}
3536 			m->m_len = min(MCLBYTES, sopt_size);
3537 		} else {
3538 			m->m_len = min(MLEN, sopt_size);
3539 		}
3540 		sopt_size -= m->m_len;
3541 		m_prev->m_next = m;
3542 		m_prev = m;
3543 	}
3544 	return (0);
3545 }
3546 
3547 int
3548 soopt_mcopyin(struct sockopt *sopt, struct mbuf *m)
3549 {
3550 	struct mbuf *m0 = m;
3551 
3552 	if (sopt->sopt_val == NULL)
3553 		return (0);
3554 	while (m != NULL && sopt->sopt_valsize >= m->m_len) {
3555 		if (sopt->sopt_td != NULL) {
3556 			int error;
3557 
3558 			error = copyin(sopt->sopt_val, mtod(m, char *),
3559 			    m->m_len);
3560 			if (error != 0) {
3561 				m_freem(m0);
3562 				return(error);
3563 			}
3564 		} else
3565 			bcopy(sopt->sopt_val, mtod(m, char *), m->m_len);
3566 		sopt->sopt_valsize -= m->m_len;
3567 		sopt->sopt_val = (char *)sopt->sopt_val + m->m_len;
3568 		m = m->m_next;
3569 	}
3570 	if (m != NULL) /* should be allocated enoughly at ip6_sooptmcopyin() */
3571 		panic("ip6_sooptmcopyin");
3572 	return (0);
3573 }
3574 
3575 int
3576 soopt_mcopyout(struct sockopt *sopt, struct mbuf *m)
3577 {
3578 	struct mbuf *m0 = m;
3579 	size_t valsize = 0;
3580 
3581 	if (sopt->sopt_val == NULL)
3582 		return (0);
3583 	while (m != NULL && sopt->sopt_valsize >= m->m_len) {
3584 		if (sopt->sopt_td != NULL) {
3585 			int error;
3586 
3587 			error = copyout(mtod(m, char *), sopt->sopt_val,
3588 			    m->m_len);
3589 			if (error != 0) {
3590 				m_freem(m0);
3591 				return(error);
3592 			}
3593 		} else
3594 			bcopy(mtod(m, char *), sopt->sopt_val, m->m_len);
3595 		sopt->sopt_valsize -= m->m_len;
3596 		sopt->sopt_val = (char *)sopt->sopt_val + m->m_len;
3597 		valsize += m->m_len;
3598 		m = m->m_next;
3599 	}
3600 	if (m != NULL) {
3601 		/* enough soopt buffer should be given from user-land */
3602 		m_freem(m0);
3603 		return(EINVAL);
3604 	}
3605 	sopt->sopt_valsize = valsize;
3606 	return (0);
3607 }
3608 
3609 /*
3610  * sohasoutofband(): protocol notifies socket layer of the arrival of new
3611  * out-of-band data, which will then notify socket consumers.
3612  */
3613 void
3614 sohasoutofband(struct socket *so)
3615 {
3616 
3617 	if (so->so_sigio != NULL)
3618 		pgsigio(&so->so_sigio, SIGURG, 0);
3619 	selwakeuppri(&so->so_rdsel, PSOCK);
3620 }
3621 
3622 int
3623 sopoll(struct socket *so, int events, struct ucred *active_cred,
3624     struct thread *td)
3625 {
3626 
3627 	/*
3628 	 * We do not need to set or assert curvnet as long as everyone uses
3629 	 * sopoll_generic().
3630 	 */
3631 	return (so->so_proto->pr_sopoll(so, events, active_cred, td));
3632 }
3633 
3634 int
3635 sopoll_generic(struct socket *so, int events, struct ucred *active_cred,
3636     struct thread *td)
3637 {
3638 	int revents;
3639 
3640 	SOCK_LOCK(so);
3641 	if (SOLISTENING(so)) {
3642 		if (!(events & (POLLIN | POLLRDNORM)))
3643 			revents = 0;
3644 		else if (!TAILQ_EMPTY(&so->sol_comp))
3645 			revents = events & (POLLIN | POLLRDNORM);
3646 		else if ((events & POLLINIGNEOF) == 0 && so->so_error)
3647 			revents = (events & (POLLIN | POLLRDNORM)) | POLLHUP;
3648 		else {
3649 			selrecord(td, &so->so_rdsel);
3650 			revents = 0;
3651 		}
3652 	} else {
3653 		revents = 0;
3654 		SOCK_SENDBUF_LOCK(so);
3655 		SOCK_RECVBUF_LOCK(so);
3656 		if (events & (POLLIN | POLLRDNORM))
3657 			if (soreadabledata(so))
3658 				revents |= events & (POLLIN | POLLRDNORM);
3659 		if (events & (POLLOUT | POLLWRNORM))
3660 			if (sowriteable(so))
3661 				revents |= events & (POLLOUT | POLLWRNORM);
3662 		if (events & (POLLPRI | POLLRDBAND))
3663 			if (so->so_oobmark ||
3664 			    (so->so_rcv.sb_state & SBS_RCVATMARK))
3665 				revents |= events & (POLLPRI | POLLRDBAND);
3666 		if ((events & POLLINIGNEOF) == 0) {
3667 			if (so->so_rcv.sb_state & SBS_CANTRCVMORE) {
3668 				revents |= events & (POLLIN | POLLRDNORM);
3669 				if (so->so_snd.sb_state & SBS_CANTSENDMORE)
3670 					revents |= POLLHUP;
3671 			}
3672 		}
3673 		if (so->so_rcv.sb_state & SBS_CANTRCVMORE)
3674 			revents |= events & POLLRDHUP;
3675 		if (revents == 0) {
3676 			if (events &
3677 			    (POLLIN | POLLPRI | POLLRDNORM | POLLRDBAND | POLLRDHUP)) {
3678 				selrecord(td, &so->so_rdsel);
3679 				so->so_rcv.sb_flags |= SB_SEL;
3680 			}
3681 			if (events & (POLLOUT | POLLWRNORM)) {
3682 				selrecord(td, &so->so_wrsel);
3683 				so->so_snd.sb_flags |= SB_SEL;
3684 			}
3685 		}
3686 		SOCK_RECVBUF_UNLOCK(so);
3687 		SOCK_SENDBUF_UNLOCK(so);
3688 	}
3689 	SOCK_UNLOCK(so);
3690 	return (revents);
3691 }
3692 
3693 int
3694 soo_kqfilter(struct file *fp, struct knote *kn)
3695 {
3696 	struct socket *so = kn->kn_fp->f_data;
3697 	struct sockbuf *sb;
3698 	sb_which which;
3699 	struct knlist *knl;
3700 
3701 	switch (kn->kn_filter) {
3702 	case EVFILT_READ:
3703 		kn->kn_fop = &soread_filtops;
3704 		knl = &so->so_rdsel.si_note;
3705 		sb = &so->so_rcv;
3706 		which = SO_RCV;
3707 		break;
3708 	case EVFILT_WRITE:
3709 		kn->kn_fop = &sowrite_filtops;
3710 		knl = &so->so_wrsel.si_note;
3711 		sb = &so->so_snd;
3712 		which = SO_SND;
3713 		break;
3714 	case EVFILT_EMPTY:
3715 		kn->kn_fop = &soempty_filtops;
3716 		knl = &so->so_wrsel.si_note;
3717 		sb = &so->so_snd;
3718 		which = SO_SND;
3719 		break;
3720 	default:
3721 		return (EINVAL);
3722 	}
3723 
3724 	SOCK_LOCK(so);
3725 	if (SOLISTENING(so)) {
3726 		knlist_add(knl, kn, 1);
3727 	} else {
3728 		SOCK_BUF_LOCK(so, which);
3729 		knlist_add(knl, kn, 1);
3730 		sb->sb_flags |= SB_KNOTE;
3731 		SOCK_BUF_UNLOCK(so, which);
3732 	}
3733 	SOCK_UNLOCK(so);
3734 	return (0);
3735 }
3736 
3737 static void
3738 filt_sordetach(struct knote *kn)
3739 {
3740 	struct socket *so = kn->kn_fp->f_data;
3741 
3742 	so_rdknl_lock(so);
3743 	knlist_remove(&so->so_rdsel.si_note, kn, 1);
3744 	if (!SOLISTENING(so) && knlist_empty(&so->so_rdsel.si_note))
3745 		so->so_rcv.sb_flags &= ~SB_KNOTE;
3746 	so_rdknl_unlock(so);
3747 }
3748 
3749 /*ARGSUSED*/
3750 static int
3751 filt_soread(struct knote *kn, long hint)
3752 {
3753 	struct socket *so;
3754 
3755 	so = kn->kn_fp->f_data;
3756 
3757 	if (SOLISTENING(so)) {
3758 		SOCK_LOCK_ASSERT(so);
3759 		kn->kn_data = so->sol_qlen;
3760 		if (so->so_error) {
3761 			kn->kn_flags |= EV_EOF;
3762 			kn->kn_fflags = so->so_error;
3763 			return (1);
3764 		}
3765 		return (!TAILQ_EMPTY(&so->sol_comp));
3766 	}
3767 
3768 	SOCK_RECVBUF_LOCK_ASSERT(so);
3769 
3770 	kn->kn_data = sbavail(&so->so_rcv) - so->so_rcv.sb_ctl;
3771 	if (so->so_rcv.sb_state & SBS_CANTRCVMORE) {
3772 		kn->kn_flags |= EV_EOF;
3773 		kn->kn_fflags = so->so_error;
3774 		return (1);
3775 	} else if (so->so_error || so->so_rerror)
3776 		return (1);
3777 
3778 	if (kn->kn_sfflags & NOTE_LOWAT) {
3779 		if (kn->kn_data >= kn->kn_sdata)
3780 			return (1);
3781 	} else if (sbavail(&so->so_rcv) >= so->so_rcv.sb_lowat)
3782 		return (1);
3783 
3784 	/* This hook returning non-zero indicates an event, not error */
3785 	return (hhook_run_socket(so, NULL, HHOOK_FILT_SOREAD));
3786 }
3787 
3788 static void
3789 filt_sowdetach(struct knote *kn)
3790 {
3791 	struct socket *so = kn->kn_fp->f_data;
3792 
3793 	so_wrknl_lock(so);
3794 	knlist_remove(&so->so_wrsel.si_note, kn, 1);
3795 	if (!SOLISTENING(so) && knlist_empty(&so->so_wrsel.si_note))
3796 		so->so_snd.sb_flags &= ~SB_KNOTE;
3797 	so_wrknl_unlock(so);
3798 }
3799 
3800 /*ARGSUSED*/
3801 static int
3802 filt_sowrite(struct knote *kn, long hint)
3803 {
3804 	struct socket *so;
3805 
3806 	so = kn->kn_fp->f_data;
3807 
3808 	if (SOLISTENING(so))
3809 		return (0);
3810 
3811 	SOCK_SENDBUF_LOCK_ASSERT(so);
3812 	kn->kn_data = sbspace(&so->so_snd);
3813 
3814 	hhook_run_socket(so, kn, HHOOK_FILT_SOWRITE);
3815 
3816 	if (so->so_snd.sb_state & SBS_CANTSENDMORE) {
3817 		kn->kn_flags |= EV_EOF;
3818 		kn->kn_fflags = so->so_error;
3819 		return (1);
3820 	} else if (so->so_error)	/* temporary udp error */
3821 		return (1);
3822 	else if (((so->so_state & SS_ISCONNECTED) == 0) &&
3823 	    (so->so_proto->pr_flags & PR_CONNREQUIRED))
3824 		return (0);
3825 	else if (kn->kn_sfflags & NOTE_LOWAT)
3826 		return (kn->kn_data >= kn->kn_sdata);
3827 	else
3828 		return (kn->kn_data >= so->so_snd.sb_lowat);
3829 }
3830 
3831 static int
3832 filt_soempty(struct knote *kn, long hint)
3833 {
3834 	struct socket *so;
3835 
3836 	so = kn->kn_fp->f_data;
3837 
3838 	if (SOLISTENING(so))
3839 		return (1);
3840 
3841 	SOCK_SENDBUF_LOCK_ASSERT(so);
3842 	kn->kn_data = sbused(&so->so_snd);
3843 
3844 	if (kn->kn_data == 0)
3845 		return (1);
3846 	else
3847 		return (0);
3848 }
3849 
3850 int
3851 socheckuid(struct socket *so, uid_t uid)
3852 {
3853 
3854 	if (so == NULL)
3855 		return (EPERM);
3856 	if (so->so_cred->cr_uid != uid)
3857 		return (EPERM);
3858 	return (0);
3859 }
3860 
3861 /*
3862  * These functions are used by protocols to notify the socket layer (and its
3863  * consumers) of state changes in the sockets driven by protocol-side events.
3864  */
3865 
3866 /*
3867  * Procedures to manipulate state flags of socket and do appropriate wakeups.
3868  *
3869  * Normal sequence from the active (originating) side is that
3870  * soisconnecting() is called during processing of connect() call, resulting
3871  * in an eventual call to soisconnected() if/when the connection is
3872  * established.  When the connection is torn down soisdisconnecting() is
3873  * called during processing of disconnect() call, and soisdisconnected() is
3874  * called when the connection to the peer is totally severed.  The semantics
3875  * of these routines are such that connectionless protocols can call
3876  * soisconnected() and soisdisconnected() only, bypassing the in-progress
3877  * calls when setting up a ``connection'' takes no time.
3878  *
3879  * From the passive side, a socket is created with two queues of sockets:
3880  * so_incomp for connections in progress and so_comp for connections already
3881  * made and awaiting user acceptance.  As a protocol is preparing incoming
3882  * connections, it creates a socket structure queued on so_incomp by calling
3883  * sonewconn().  When the connection is established, soisconnected() is
3884  * called, and transfers the socket structure to so_comp, making it available
3885  * to accept().
3886  *
3887  * If a socket is closed with sockets on either so_incomp or so_comp, these
3888  * sockets are dropped.
3889  *
3890  * If higher-level protocols are implemented in the kernel, the wakeups done
3891  * here will sometimes cause software-interrupt process scheduling.
3892  */
3893 void
3894 soisconnecting(struct socket *so)
3895 {
3896 
3897 	SOCK_LOCK(so);
3898 	so->so_state &= ~(SS_ISCONNECTED|SS_ISDISCONNECTING);
3899 	so->so_state |= SS_ISCONNECTING;
3900 	SOCK_UNLOCK(so);
3901 }
3902 
3903 void
3904 soisconnected(struct socket *so)
3905 {
3906 	bool last __diagused;
3907 
3908 	SOCK_LOCK(so);
3909 	so->so_state &= ~(SS_ISCONNECTING|SS_ISDISCONNECTING|SS_ISCONFIRMING);
3910 	so->so_state |= SS_ISCONNECTED;
3911 
3912 	if (so->so_qstate == SQ_INCOMP) {
3913 		struct socket *head = so->so_listen;
3914 		int ret;
3915 
3916 		KASSERT(head, ("%s: so %p on incomp of NULL", __func__, so));
3917 		/*
3918 		 * Promoting a socket from incomplete queue to complete, we
3919 		 * need to go through reverse order of locking.  We first do
3920 		 * trylock, and if that doesn't succeed, we go the hard way
3921 		 * leaving a reference and rechecking consistency after proper
3922 		 * locking.
3923 		 */
3924 		if (__predict_false(SOLISTEN_TRYLOCK(head) == 0)) {
3925 			soref(head);
3926 			SOCK_UNLOCK(so);
3927 			SOLISTEN_LOCK(head);
3928 			SOCK_LOCK(so);
3929 			if (__predict_false(head != so->so_listen)) {
3930 				/*
3931 				 * The socket went off the listen queue,
3932 				 * should be lost race to close(2) of sol.
3933 				 * The socket is about to soabort().
3934 				 */
3935 				SOCK_UNLOCK(so);
3936 				sorele_locked(head);
3937 				return;
3938 			}
3939 			last = refcount_release(&head->so_count);
3940 			KASSERT(!last, ("%s: released last reference for %p",
3941 			    __func__, head));
3942 		}
3943 again:
3944 		if ((so->so_options & SO_ACCEPTFILTER) == 0) {
3945 			TAILQ_REMOVE(&head->sol_incomp, so, so_list);
3946 			head->sol_incqlen--;
3947 			TAILQ_INSERT_TAIL(&head->sol_comp, so, so_list);
3948 			head->sol_qlen++;
3949 			so->so_qstate = SQ_COMP;
3950 			SOCK_UNLOCK(so);
3951 			solisten_wakeup(head);	/* unlocks */
3952 		} else {
3953 			SOCK_RECVBUF_LOCK(so);
3954 			soupcall_set(so, SO_RCV,
3955 			    head->sol_accept_filter->accf_callback,
3956 			    head->sol_accept_filter_arg);
3957 			so->so_options &= ~SO_ACCEPTFILTER;
3958 			ret = head->sol_accept_filter->accf_callback(so,
3959 			    head->sol_accept_filter_arg, M_NOWAIT);
3960 			if (ret == SU_ISCONNECTED) {
3961 				soupcall_clear(so, SO_RCV);
3962 				SOCK_RECVBUF_UNLOCK(so);
3963 				goto again;
3964 			}
3965 			SOCK_RECVBUF_UNLOCK(so);
3966 			SOCK_UNLOCK(so);
3967 			SOLISTEN_UNLOCK(head);
3968 		}
3969 		return;
3970 	}
3971 	SOCK_UNLOCK(so);
3972 	wakeup(&so->so_timeo);
3973 	sorwakeup(so);
3974 	sowwakeup(so);
3975 }
3976 
3977 void
3978 soisdisconnecting(struct socket *so)
3979 {
3980 
3981 	SOCK_LOCK(so);
3982 	so->so_state &= ~SS_ISCONNECTING;
3983 	so->so_state |= SS_ISDISCONNECTING;
3984 
3985 	if (!SOLISTENING(so)) {
3986 		SOCK_RECVBUF_LOCK(so);
3987 		socantrcvmore_locked(so);
3988 		SOCK_SENDBUF_LOCK(so);
3989 		socantsendmore_locked(so);
3990 	}
3991 	SOCK_UNLOCK(so);
3992 	wakeup(&so->so_timeo);
3993 }
3994 
3995 void
3996 soisdisconnected(struct socket *so)
3997 {
3998 
3999 	SOCK_LOCK(so);
4000 
4001 	/*
4002 	 * There is at least one reader of so_state that does not
4003 	 * acquire socket lock, namely soreceive_generic().  Ensure
4004 	 * that it never sees all flags that track connection status
4005 	 * cleared, by ordering the update with a barrier semantic of
4006 	 * our release thread fence.
4007 	 */
4008 	so->so_state |= SS_ISDISCONNECTED;
4009 	atomic_thread_fence_rel();
4010 	so->so_state &= ~(SS_ISCONNECTING|SS_ISCONNECTED|SS_ISDISCONNECTING);
4011 
4012 	if (!SOLISTENING(so)) {
4013 		SOCK_UNLOCK(so);
4014 		SOCK_RECVBUF_LOCK(so);
4015 		socantrcvmore_locked(so);
4016 		SOCK_SENDBUF_LOCK(so);
4017 		sbdrop_locked(&so->so_snd, sbused(&so->so_snd));
4018 		socantsendmore_locked(so);
4019 	} else
4020 		SOCK_UNLOCK(so);
4021 	wakeup(&so->so_timeo);
4022 }
4023 
4024 int
4025 soiolock(struct socket *so, struct sx *sx, int flags)
4026 {
4027 	int error;
4028 
4029 	KASSERT((flags & SBL_VALID) == flags,
4030 	    ("soiolock: invalid flags %#x", flags));
4031 
4032 	if ((flags & SBL_WAIT) != 0) {
4033 		if ((flags & SBL_NOINTR) != 0) {
4034 			sx_xlock(sx);
4035 		} else {
4036 			error = sx_xlock_sig(sx);
4037 			if (error != 0)
4038 				return (error);
4039 		}
4040 	} else if (!sx_try_xlock(sx)) {
4041 		return (EWOULDBLOCK);
4042 	}
4043 
4044 	if (__predict_false(SOLISTENING(so))) {
4045 		sx_xunlock(sx);
4046 		return (ENOTCONN);
4047 	}
4048 	return (0);
4049 }
4050 
4051 void
4052 soiounlock(struct sx *sx)
4053 {
4054 	sx_xunlock(sx);
4055 }
4056 
4057 /*
4058  * Make a copy of a sockaddr in a malloced buffer of type M_SONAME.
4059  */
4060 struct sockaddr *
4061 sodupsockaddr(const struct sockaddr *sa, int mflags)
4062 {
4063 	struct sockaddr *sa2;
4064 
4065 	sa2 = malloc(sa->sa_len, M_SONAME, mflags);
4066 	if (sa2)
4067 		bcopy(sa, sa2, sa->sa_len);
4068 	return sa2;
4069 }
4070 
4071 /*
4072  * Register per-socket destructor.
4073  */
4074 void
4075 sodtor_set(struct socket *so, so_dtor_t *func)
4076 {
4077 
4078 	SOCK_LOCK_ASSERT(so);
4079 	so->so_dtor = func;
4080 }
4081 
4082 /*
4083  * Register per-socket buffer upcalls.
4084  */
4085 void
4086 soupcall_set(struct socket *so, sb_which which, so_upcall_t func, void *arg)
4087 {
4088 	struct sockbuf *sb;
4089 
4090 	KASSERT(!SOLISTENING(so), ("%s: so %p listening", __func__, so));
4091 
4092 	switch (which) {
4093 	case SO_RCV:
4094 		sb = &so->so_rcv;
4095 		break;
4096 	case SO_SND:
4097 		sb = &so->so_snd;
4098 		break;
4099 	}
4100 	SOCK_BUF_LOCK_ASSERT(so, which);
4101 	sb->sb_upcall = func;
4102 	sb->sb_upcallarg = arg;
4103 	sb->sb_flags |= SB_UPCALL;
4104 }
4105 
4106 void
4107 soupcall_clear(struct socket *so, sb_which which)
4108 {
4109 	struct sockbuf *sb;
4110 
4111 	KASSERT(!SOLISTENING(so), ("%s: so %p listening", __func__, so));
4112 
4113 	switch (which) {
4114 	case SO_RCV:
4115 		sb = &so->so_rcv;
4116 		break;
4117 	case SO_SND:
4118 		sb = &so->so_snd;
4119 		break;
4120 	}
4121 	SOCK_BUF_LOCK_ASSERT(so, which);
4122 	KASSERT(sb->sb_upcall != NULL,
4123 	    ("%s: so %p no upcall to clear", __func__, so));
4124 	sb->sb_upcall = NULL;
4125 	sb->sb_upcallarg = NULL;
4126 	sb->sb_flags &= ~SB_UPCALL;
4127 }
4128 
4129 void
4130 solisten_upcall_set(struct socket *so, so_upcall_t func, void *arg)
4131 {
4132 
4133 	SOLISTEN_LOCK_ASSERT(so);
4134 	so->sol_upcall = func;
4135 	so->sol_upcallarg = arg;
4136 }
4137 
4138 static void
4139 so_rdknl_lock(void *arg)
4140 {
4141 	struct socket *so = arg;
4142 
4143 retry:
4144 	if (SOLISTENING(so)) {
4145 		SOLISTEN_LOCK(so);
4146 	} else {
4147 		SOCK_RECVBUF_LOCK(so);
4148 		if (__predict_false(SOLISTENING(so))) {
4149 			SOCK_RECVBUF_UNLOCK(so);
4150 			goto retry;
4151 		}
4152 	}
4153 }
4154 
4155 static void
4156 so_rdknl_unlock(void *arg)
4157 {
4158 	struct socket *so = arg;
4159 
4160 	if (SOLISTENING(so))
4161 		SOLISTEN_UNLOCK(so);
4162 	else
4163 		SOCK_RECVBUF_UNLOCK(so);
4164 }
4165 
4166 static void
4167 so_rdknl_assert_lock(void *arg, int what)
4168 {
4169 	struct socket *so = arg;
4170 
4171 	if (what == LA_LOCKED) {
4172 		if (SOLISTENING(so))
4173 			SOLISTEN_LOCK_ASSERT(so);
4174 		else
4175 			SOCK_RECVBUF_LOCK_ASSERT(so);
4176 	} else {
4177 		if (SOLISTENING(so))
4178 			SOLISTEN_UNLOCK_ASSERT(so);
4179 		else
4180 			SOCK_RECVBUF_UNLOCK_ASSERT(so);
4181 	}
4182 }
4183 
4184 static void
4185 so_wrknl_lock(void *arg)
4186 {
4187 	struct socket *so = arg;
4188 
4189 retry:
4190 	if (SOLISTENING(so)) {
4191 		SOLISTEN_LOCK(so);
4192 	} else {
4193 		SOCK_SENDBUF_LOCK(so);
4194 		if (__predict_false(SOLISTENING(so))) {
4195 			SOCK_SENDBUF_UNLOCK(so);
4196 			goto retry;
4197 		}
4198 	}
4199 }
4200 
4201 static void
4202 so_wrknl_unlock(void *arg)
4203 {
4204 	struct socket *so = arg;
4205 
4206 	if (SOLISTENING(so))
4207 		SOLISTEN_UNLOCK(so);
4208 	else
4209 		SOCK_SENDBUF_UNLOCK(so);
4210 }
4211 
4212 static void
4213 so_wrknl_assert_lock(void *arg, int what)
4214 {
4215 	struct socket *so = arg;
4216 
4217 	if (what == LA_LOCKED) {
4218 		if (SOLISTENING(so))
4219 			SOLISTEN_LOCK_ASSERT(so);
4220 		else
4221 			SOCK_SENDBUF_LOCK_ASSERT(so);
4222 	} else {
4223 		if (SOLISTENING(so))
4224 			SOLISTEN_UNLOCK_ASSERT(so);
4225 		else
4226 			SOCK_SENDBUF_UNLOCK_ASSERT(so);
4227 	}
4228 }
4229 
4230 /*
4231  * Create an external-format (``xsocket'') structure using the information in
4232  * the kernel-format socket structure pointed to by so.  This is done to
4233  * reduce the spew of irrelevant information over this interface, to isolate
4234  * user code from changes in the kernel structure, and potentially to provide
4235  * information-hiding if we decide that some of this information should be
4236  * hidden from users.
4237  */
4238 void
4239 sotoxsocket(struct socket *so, struct xsocket *xso)
4240 {
4241 
4242 	bzero(xso, sizeof(*xso));
4243 	xso->xso_len = sizeof *xso;
4244 	xso->xso_so = (uintptr_t)so;
4245 	xso->so_type = so->so_type;
4246 	xso->so_options = so->so_options;
4247 	xso->so_linger = so->so_linger;
4248 	xso->so_state = so->so_state;
4249 	xso->so_pcb = (uintptr_t)so->so_pcb;
4250 	xso->xso_protocol = so->so_proto->pr_protocol;
4251 	xso->xso_family = so->so_proto->pr_domain->dom_family;
4252 	xso->so_timeo = so->so_timeo;
4253 	xso->so_error = so->so_error;
4254 	xso->so_uid = so->so_cred->cr_uid;
4255 	xso->so_pgid = so->so_sigio ? so->so_sigio->sio_pgid : 0;
4256 	if (SOLISTENING(so)) {
4257 		xso->so_qlen = so->sol_qlen;
4258 		xso->so_incqlen = so->sol_incqlen;
4259 		xso->so_qlimit = so->sol_qlimit;
4260 		xso->so_oobmark = 0;
4261 	} else {
4262 		xso->so_state |= so->so_qstate;
4263 		xso->so_qlen = xso->so_incqlen = xso->so_qlimit = 0;
4264 		xso->so_oobmark = so->so_oobmark;
4265 		sbtoxsockbuf(&so->so_snd, &xso->so_snd);
4266 		sbtoxsockbuf(&so->so_rcv, &xso->so_rcv);
4267 	}
4268 }
4269 
4270 struct sockbuf *
4271 so_sockbuf_rcv(struct socket *so)
4272 {
4273 
4274 	return (&so->so_rcv);
4275 }
4276 
4277 struct sockbuf *
4278 so_sockbuf_snd(struct socket *so)
4279 {
4280 
4281 	return (&so->so_snd);
4282 }
4283 
4284 int
4285 so_state_get(const struct socket *so)
4286 {
4287 
4288 	return (so->so_state);
4289 }
4290 
4291 void
4292 so_state_set(struct socket *so, int val)
4293 {
4294 
4295 	so->so_state = val;
4296 }
4297 
4298 int
4299 so_options_get(const struct socket *so)
4300 {
4301 
4302 	return (so->so_options);
4303 }
4304 
4305 void
4306 so_options_set(struct socket *so, int val)
4307 {
4308 
4309 	so->so_options = val;
4310 }
4311 
4312 int
4313 so_error_get(const struct socket *so)
4314 {
4315 
4316 	return (so->so_error);
4317 }
4318 
4319 void
4320 so_error_set(struct socket *so, int val)
4321 {
4322 
4323 	so->so_error = val;
4324 }
4325 
4326 int
4327 so_linger_get(const struct socket *so)
4328 {
4329 
4330 	return (so->so_linger);
4331 }
4332 
4333 void
4334 so_linger_set(struct socket *so, int val)
4335 {
4336 
4337 	KASSERT(val >= 0 && val <= USHRT_MAX && val <= (INT_MAX / hz),
4338 	    ("%s: val %d out of range", __func__, val));
4339 
4340 	so->so_linger = val;
4341 }
4342 
4343 struct protosw *
4344 so_protosw_get(const struct socket *so)
4345 {
4346 
4347 	return (so->so_proto);
4348 }
4349 
4350 void
4351 so_protosw_set(struct socket *so, struct protosw *val)
4352 {
4353 
4354 	so->so_proto = val;
4355 }
4356 
4357 void
4358 so_sorwakeup(struct socket *so)
4359 {
4360 
4361 	sorwakeup(so);
4362 }
4363 
4364 void
4365 so_sowwakeup(struct socket *so)
4366 {
4367 
4368 	sowwakeup(so);
4369 }
4370 
4371 void
4372 so_sorwakeup_locked(struct socket *so)
4373 {
4374 
4375 	sorwakeup_locked(so);
4376 }
4377 
4378 void
4379 so_sowwakeup_locked(struct socket *so)
4380 {
4381 
4382 	sowwakeup_locked(so);
4383 }
4384 
4385 void
4386 so_lock(struct socket *so)
4387 {
4388 
4389 	SOCK_LOCK(so);
4390 }
4391 
4392 void
4393 so_unlock(struct socket *so)
4394 {
4395 
4396 	SOCK_UNLOCK(so);
4397 }
4398