xref: /freebsd/sys/kern/uipc_socket.c (revision 2b833162)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1982, 1986, 1988, 1990, 1993
5  *	The Regents of the University of California.
6  * Copyright (c) 2004 The FreeBSD Foundation
7  * Copyright (c) 2004-2008 Robert N. M. Watson
8  * All rights reserved.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  *	@(#)uipc_socket.c	8.3 (Berkeley) 4/15/94
35  */
36 
37 /*
38  * Comments on the socket life cycle:
39  *
40  * soalloc() sets of socket layer state for a socket, called only by
41  * socreate() and sonewconn().  Socket layer private.
42  *
43  * sodealloc() tears down socket layer state for a socket, called only by
44  * sofree() and sonewconn().  Socket layer private.
45  *
46  * pru_attach() associates protocol layer state with an allocated socket;
47  * called only once, may fail, aborting socket allocation.  This is called
48  * from socreate() and sonewconn().  Socket layer private.
49  *
50  * pru_detach() disassociates protocol layer state from an attached socket,
51  * and will be called exactly once for sockets in which pru_attach() has
52  * been successfully called.  If pru_attach() returned an error,
53  * pru_detach() will not be called.  Socket layer private.
54  *
55  * pru_abort() and pru_close() notify the protocol layer that the last
56  * consumer of a socket is starting to tear down the socket, and that the
57  * protocol should terminate the connection.  Historically, pru_abort() also
58  * detached protocol state from the socket state, but this is no longer the
59  * case.
60  *
61  * socreate() creates a socket and attaches protocol state.  This is a public
62  * interface that may be used by socket layer consumers to create new
63  * sockets.
64  *
65  * sonewconn() creates a socket and attaches protocol state.  This is a
66  * public interface  that may be used by protocols to create new sockets when
67  * a new connection is received and will be available for accept() on a
68  * listen socket.
69  *
70  * soclose() destroys a socket after possibly waiting for it to disconnect.
71  * This is a public interface that socket consumers should use to close and
72  * release a socket when done with it.
73  *
74  * soabort() destroys a socket without waiting for it to disconnect (used
75  * only for incoming connections that are already partially or fully
76  * connected).  This is used internally by the socket layer when clearing
77  * listen socket queues (due to overflow or close on the listen socket), but
78  * is also a public interface protocols may use to abort connections in
79  * their incomplete listen queues should they no longer be required.  Sockets
80  * placed in completed connection listen queues should not be aborted for
81  * reasons described in the comment above the soclose() implementation.  This
82  * is not a general purpose close routine, and except in the specific
83  * circumstances described here, should not be used.
84  *
85  * sofree() will free a socket and its protocol state if all references on
86  * the socket have been released, and is the public interface to attempt to
87  * free a socket when a reference is removed.  This is a socket layer private
88  * interface.
89  *
90  * NOTE: In addition to socreate() and soclose(), which provide a single
91  * socket reference to the consumer to be managed as required, there are two
92  * calls to explicitly manage socket references, soref(), and sorele().
93  * Currently, these are generally required only when transitioning a socket
94  * from a listen queue to a file descriptor, in order to prevent garbage
95  * collection of the socket at an untimely moment.  For a number of reasons,
96  * these interfaces are not preferred, and should be avoided.
97  *
98  * NOTE: With regard to VNETs the general rule is that callers do not set
99  * curvnet. Exceptions to this rule include soabort(), sodisconnect(),
100  * sofree() (and with that sorele(), sotryfree()), as well as sonewconn()
101  * and sorflush(), which are usually called from a pre-set VNET context.
102  * sopoll() currently does not need a VNET context to be set.
103  */
104 
105 #include <sys/cdefs.h>
106 __FBSDID("$FreeBSD$");
107 
108 #include "opt_inet.h"
109 #include "opt_inet6.h"
110 #include "opt_kern_tls.h"
111 #include "opt_sctp.h"
112 
113 #include <sys/param.h>
114 #include <sys/systm.h>
115 #include <sys/capsicum.h>
116 #include <sys/fcntl.h>
117 #include <sys/limits.h>
118 #include <sys/lock.h>
119 #include <sys/mac.h>
120 #include <sys/malloc.h>
121 #include <sys/mbuf.h>
122 #include <sys/mutex.h>
123 #include <sys/domain.h>
124 #include <sys/file.h>			/* for struct knote */
125 #include <sys/hhook.h>
126 #include <sys/kernel.h>
127 #include <sys/khelp.h>
128 #include <sys/ktls.h>
129 #include <sys/event.h>
130 #include <sys/eventhandler.h>
131 #include <sys/poll.h>
132 #include <sys/proc.h>
133 #include <sys/protosw.h>
134 #include <sys/sbuf.h>
135 #include <sys/socket.h>
136 #include <sys/socketvar.h>
137 #include <sys/resourcevar.h>
138 #include <net/route.h>
139 #include <sys/signalvar.h>
140 #include <sys/stat.h>
141 #include <sys/sx.h>
142 #include <sys/sysctl.h>
143 #include <sys/taskqueue.h>
144 #include <sys/uio.h>
145 #include <sys/un.h>
146 #include <sys/unpcb.h>
147 #include <sys/jail.h>
148 #include <sys/syslog.h>
149 #include <netinet/in.h>
150 #include <netinet/in_pcb.h>
151 #include <netinet/tcp.h>
152 
153 #include <net/vnet.h>
154 
155 #include <security/mac/mac_framework.h>
156 
157 #include <vm/uma.h>
158 
159 #ifdef COMPAT_FREEBSD32
160 #include <sys/mount.h>
161 #include <sys/sysent.h>
162 #include <compat/freebsd32/freebsd32.h>
163 #endif
164 
165 static int	soreceive_rcvoob(struct socket *so, struct uio *uio,
166 		    int flags);
167 static void	so_rdknl_lock(void *);
168 static void	so_rdknl_unlock(void *);
169 static void	so_rdknl_assert_lock(void *, int);
170 static void	so_wrknl_lock(void *);
171 static void	so_wrknl_unlock(void *);
172 static void	so_wrknl_assert_lock(void *, int);
173 
174 static void	filt_sordetach(struct knote *kn);
175 static int	filt_soread(struct knote *kn, long hint);
176 static void	filt_sowdetach(struct knote *kn);
177 static int	filt_sowrite(struct knote *kn, long hint);
178 static int	filt_soempty(struct knote *kn, long hint);
179 static int inline hhook_run_socket(struct socket *so, void *hctx, int32_t h_id);
180 fo_kqfilter_t	soo_kqfilter;
181 
182 static struct filterops soread_filtops = {
183 	.f_isfd = 1,
184 	.f_detach = filt_sordetach,
185 	.f_event = filt_soread,
186 };
187 static struct filterops sowrite_filtops = {
188 	.f_isfd = 1,
189 	.f_detach = filt_sowdetach,
190 	.f_event = filt_sowrite,
191 };
192 static struct filterops soempty_filtops = {
193 	.f_isfd = 1,
194 	.f_detach = filt_sowdetach,
195 	.f_event = filt_soempty,
196 };
197 
198 so_gen_t	so_gencnt;	/* generation count for sockets */
199 
200 MALLOC_DEFINE(M_SONAME, "soname", "socket name");
201 MALLOC_DEFINE(M_PCB, "pcb", "protocol control block");
202 
203 #define	VNET_SO_ASSERT(so)						\
204 	VNET_ASSERT(curvnet != NULL,					\
205 	    ("%s:%d curvnet is NULL, so=%p", __func__, __LINE__, (so)));
206 
207 VNET_DEFINE(struct hhook_head *, socket_hhh[HHOOK_SOCKET_LAST + 1]);
208 #define	V_socket_hhh		VNET(socket_hhh)
209 
210 /*
211  * Limit on the number of connections in the listen queue waiting
212  * for accept(2).
213  * NB: The original sysctl somaxconn is still available but hidden
214  * to prevent confusion about the actual purpose of this number.
215  */
216 static u_int somaxconn = SOMAXCONN;
217 
218 static int
219 sysctl_somaxconn(SYSCTL_HANDLER_ARGS)
220 {
221 	int error;
222 	int val;
223 
224 	val = somaxconn;
225 	error = sysctl_handle_int(oidp, &val, 0, req);
226 	if (error || !req->newptr )
227 		return (error);
228 
229 	/*
230 	 * The purpose of the UINT_MAX / 3 limit, is so that the formula
231 	 *   3 * so_qlimit / 2
232 	 * below, will not overflow.
233          */
234 
235 	if (val < 1 || val > UINT_MAX / 3)
236 		return (EINVAL);
237 
238 	somaxconn = val;
239 	return (0);
240 }
241 SYSCTL_PROC(_kern_ipc, OID_AUTO, soacceptqueue,
242     CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_MPSAFE, 0, sizeof(int),
243     sysctl_somaxconn, "I",
244     "Maximum listen socket pending connection accept queue size");
245 SYSCTL_PROC(_kern_ipc, KIPC_SOMAXCONN, somaxconn,
246     CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_SKIP | CTLFLAG_MPSAFE, 0,
247     sizeof(int), sysctl_somaxconn, "I",
248     "Maximum listen socket pending connection accept queue size (compat)");
249 
250 static int numopensockets;
251 SYSCTL_INT(_kern_ipc, OID_AUTO, numopensockets, CTLFLAG_RD,
252     &numopensockets, 0, "Number of open sockets");
253 
254 /*
255  * so_global_mtx protects so_gencnt, numopensockets, and the per-socket
256  * so_gencnt field.
257  */
258 static struct mtx so_global_mtx;
259 MTX_SYSINIT(so_global_mtx, &so_global_mtx, "so_glabel", MTX_DEF);
260 
261 /*
262  * General IPC sysctl name space, used by sockets and a variety of other IPC
263  * types.
264  */
265 SYSCTL_NODE(_kern, KERN_IPC, ipc, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
266     "IPC");
267 
268 /*
269  * Initialize the socket subsystem and set up the socket
270  * memory allocator.
271  */
272 static uma_zone_t socket_zone;
273 int	maxsockets;
274 
275 static void
276 socket_zone_change(void *tag)
277 {
278 
279 	maxsockets = uma_zone_set_max(socket_zone, maxsockets);
280 }
281 
282 static void
283 socket_hhook_register(int subtype)
284 {
285 
286 	if (hhook_head_register(HHOOK_TYPE_SOCKET, subtype,
287 	    &V_socket_hhh[subtype],
288 	    HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0)
289 		printf("%s: WARNING: unable to register hook\n", __func__);
290 }
291 
292 static void
293 socket_hhook_deregister(int subtype)
294 {
295 
296 	if (hhook_head_deregister(V_socket_hhh[subtype]) != 0)
297 		printf("%s: WARNING: unable to deregister hook\n", __func__);
298 }
299 
300 static void
301 socket_init(void *tag)
302 {
303 
304 	socket_zone = uma_zcreate("socket", sizeof(struct socket), NULL, NULL,
305 	    NULL, NULL, UMA_ALIGN_PTR, 0);
306 	maxsockets = uma_zone_set_max(socket_zone, maxsockets);
307 	uma_zone_set_warning(socket_zone, "kern.ipc.maxsockets limit reached");
308 	EVENTHANDLER_REGISTER(maxsockets_change, socket_zone_change, NULL,
309 	    EVENTHANDLER_PRI_FIRST);
310 }
311 SYSINIT(socket, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY, socket_init, NULL);
312 
313 static void
314 socket_vnet_init(const void *unused __unused)
315 {
316 	int i;
317 
318 	/* We expect a contiguous range */
319 	for (i = 0; i <= HHOOK_SOCKET_LAST; i++)
320 		socket_hhook_register(i);
321 }
322 VNET_SYSINIT(socket_vnet_init, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY,
323     socket_vnet_init, NULL);
324 
325 static void
326 socket_vnet_uninit(const void *unused __unused)
327 {
328 	int i;
329 
330 	for (i = 0; i <= HHOOK_SOCKET_LAST; i++)
331 		socket_hhook_deregister(i);
332 }
333 VNET_SYSUNINIT(socket_vnet_uninit, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY,
334     socket_vnet_uninit, NULL);
335 
336 /*
337  * Initialise maxsockets.  This SYSINIT must be run after
338  * tunable_mbinit().
339  */
340 static void
341 init_maxsockets(void *ignored)
342 {
343 
344 	TUNABLE_INT_FETCH("kern.ipc.maxsockets", &maxsockets);
345 	maxsockets = imax(maxsockets, maxfiles);
346 }
347 SYSINIT(param, SI_SUB_TUNABLES, SI_ORDER_ANY, init_maxsockets, NULL);
348 
349 /*
350  * Sysctl to get and set the maximum global sockets limit.  Notify protocols
351  * of the change so that they can update their dependent limits as required.
352  */
353 static int
354 sysctl_maxsockets(SYSCTL_HANDLER_ARGS)
355 {
356 	int error, newmaxsockets;
357 
358 	newmaxsockets = maxsockets;
359 	error = sysctl_handle_int(oidp, &newmaxsockets, 0, req);
360 	if (error == 0 && req->newptr && newmaxsockets != maxsockets) {
361 		if (newmaxsockets > maxsockets &&
362 		    newmaxsockets <= maxfiles) {
363 			maxsockets = newmaxsockets;
364 			EVENTHANDLER_INVOKE(maxsockets_change);
365 		} else
366 			error = EINVAL;
367 	}
368 	return (error);
369 }
370 SYSCTL_PROC(_kern_ipc, OID_AUTO, maxsockets,
371     CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, &maxsockets, 0,
372     sysctl_maxsockets, "IU",
373     "Maximum number of sockets available");
374 
375 /*
376  * Socket operation routines.  These routines are called by the routines in
377  * sys_socket.c or from a system process, and implement the semantics of
378  * socket operations by switching out to the protocol specific routines.
379  */
380 
381 /*
382  * Get a socket structure from our zone, and initialize it.  Note that it
383  * would probably be better to allocate socket and PCB at the same time, but
384  * I'm not convinced that all the protocols can be easily modified to do
385  * this.
386  *
387  * soalloc() returns a socket with a ref count of 0.
388  */
389 static struct socket *
390 soalloc(struct vnet *vnet)
391 {
392 	struct socket *so;
393 
394 	so = uma_zalloc(socket_zone, M_NOWAIT | M_ZERO);
395 	if (so == NULL)
396 		return (NULL);
397 #ifdef MAC
398 	if (mac_socket_init(so, M_NOWAIT) != 0) {
399 		uma_zfree(socket_zone, so);
400 		return (NULL);
401 	}
402 #endif
403 	if (khelp_init_osd(HELPER_CLASS_SOCKET, &so->osd)) {
404 		uma_zfree(socket_zone, so);
405 		return (NULL);
406 	}
407 
408 	/*
409 	 * The socket locking protocol allows to lock 2 sockets at a time,
410 	 * however, the first one must be a listening socket.  WITNESS lacks
411 	 * a feature to change class of an existing lock, so we use DUPOK.
412 	 */
413 	mtx_init(&so->so_lock, "socket", NULL, MTX_DEF | MTX_DUPOK);
414 	mtx_init(&so->so_snd_mtx, "so_snd", NULL, MTX_DEF);
415 	mtx_init(&so->so_rcv_mtx, "so_rcv", NULL, MTX_DEF);
416 	so->so_rcv.sb_sel = &so->so_rdsel;
417 	so->so_snd.sb_sel = &so->so_wrsel;
418 	sx_init(&so->so_snd_sx, "so_snd_sx");
419 	sx_init(&so->so_rcv_sx, "so_rcv_sx");
420 	TAILQ_INIT(&so->so_snd.sb_aiojobq);
421 	TAILQ_INIT(&so->so_rcv.sb_aiojobq);
422 	TASK_INIT(&so->so_snd.sb_aiotask, 0, soaio_snd, so);
423 	TASK_INIT(&so->so_rcv.sb_aiotask, 0, soaio_rcv, so);
424 #ifdef VIMAGE
425 	VNET_ASSERT(vnet != NULL, ("%s:%d vnet is NULL, so=%p",
426 	    __func__, __LINE__, so));
427 	so->so_vnet = vnet;
428 #endif
429 	/* We shouldn't need the so_global_mtx */
430 	if (hhook_run_socket(so, NULL, HHOOK_SOCKET_CREATE)) {
431 		/* Do we need more comprehensive error returns? */
432 		uma_zfree(socket_zone, so);
433 		return (NULL);
434 	}
435 	mtx_lock(&so_global_mtx);
436 	so->so_gencnt = ++so_gencnt;
437 	++numopensockets;
438 #ifdef VIMAGE
439 	vnet->vnet_sockcnt++;
440 #endif
441 	mtx_unlock(&so_global_mtx);
442 
443 	return (so);
444 }
445 
446 /*
447  * Free the storage associated with a socket at the socket layer, tear down
448  * locks, labels, etc.  All protocol state is assumed already to have been
449  * torn down (and possibly never set up) by the caller.
450  */
451 void
452 sodealloc(struct socket *so)
453 {
454 
455 	KASSERT(so->so_count == 0, ("sodealloc(): so_count %d", so->so_count));
456 	KASSERT(so->so_pcb == NULL, ("sodealloc(): so_pcb != NULL"));
457 
458 	mtx_lock(&so_global_mtx);
459 	so->so_gencnt = ++so_gencnt;
460 	--numopensockets;	/* Could be below, but faster here. */
461 #ifdef VIMAGE
462 	VNET_ASSERT(so->so_vnet != NULL, ("%s:%d so_vnet is NULL, so=%p",
463 	    __func__, __LINE__, so));
464 	so->so_vnet->vnet_sockcnt--;
465 #endif
466 	mtx_unlock(&so_global_mtx);
467 #ifdef MAC
468 	mac_socket_destroy(so);
469 #endif
470 	hhook_run_socket(so, NULL, HHOOK_SOCKET_CLOSE);
471 
472 	khelp_destroy_osd(&so->osd);
473 	if (SOLISTENING(so)) {
474 		if (so->sol_accept_filter != NULL)
475 			accept_filt_setopt(so, NULL);
476 	} else {
477 		if (so->so_rcv.sb_hiwat)
478 			(void)chgsbsize(so->so_cred->cr_uidinfo,
479 			    &so->so_rcv.sb_hiwat, 0, RLIM_INFINITY);
480 		if (so->so_snd.sb_hiwat)
481 			(void)chgsbsize(so->so_cred->cr_uidinfo,
482 			    &so->so_snd.sb_hiwat, 0, RLIM_INFINITY);
483 		sx_destroy(&so->so_snd_sx);
484 		sx_destroy(&so->so_rcv_sx);
485 		mtx_destroy(&so->so_snd_mtx);
486 		mtx_destroy(&so->so_rcv_mtx);
487 	}
488 	crfree(so->so_cred);
489 	mtx_destroy(&so->so_lock);
490 	uma_zfree(socket_zone, so);
491 }
492 
493 /*
494  * socreate returns a socket with a ref count of 1 and a file descriptor
495  * reference.  The socket should be closed with soclose().
496  */
497 int
498 socreate(int dom, struct socket **aso, int type, int proto,
499     struct ucred *cred, struct thread *td)
500 {
501 	struct protosw *prp;
502 	struct socket *so;
503 	int error;
504 
505 	/*
506 	 * XXX: divert(4) historically abused PF_INET.  Keep this compatibility
507 	 * shim until all applications have been updated.
508 	 */
509 	if (__predict_false(dom == PF_INET && type == SOCK_RAW &&
510 	    proto == IPPROTO_DIVERT)) {
511 		dom = PF_DIVERT;
512 		printf("%s uses obsolete way to create divert(4) socket\n",
513 		    td->td_proc->p_comm);
514 	}
515 
516 	prp = pffindproto(dom, type, proto);
517 	if (prp == NULL) {
518 		/* No support for domain. */
519 		if (pffinddomain(dom) == NULL)
520 			return (EAFNOSUPPORT);
521 		/* No support for socket type. */
522 		if (proto == 0 && type != 0)
523 			return (EPROTOTYPE);
524 		return (EPROTONOSUPPORT);
525 	}
526 
527 	MPASS(prp->pr_attach);
528 
529 	if (IN_CAPABILITY_MODE(td) && (prp->pr_flags & PR_CAPATTACH) == 0)
530 		return (ECAPMODE);
531 
532 	if (prison_check_af(cred, prp->pr_domain->dom_family) != 0)
533 		return (EPROTONOSUPPORT);
534 
535 	so = soalloc(CRED_TO_VNET(cred));
536 	if (so == NULL)
537 		return (ENOBUFS);
538 
539 	so->so_type = type;
540 	so->so_cred = crhold(cred);
541 	if ((prp->pr_domain->dom_family == PF_INET) ||
542 	    (prp->pr_domain->dom_family == PF_INET6) ||
543 	    (prp->pr_domain->dom_family == PF_ROUTE))
544 		so->so_fibnum = td->td_proc->p_fibnum;
545 	else
546 		so->so_fibnum = 0;
547 	so->so_proto = prp;
548 #ifdef MAC
549 	mac_socket_create(cred, so);
550 #endif
551 	knlist_init(&so->so_rdsel.si_note, so, so_rdknl_lock, so_rdknl_unlock,
552 	    so_rdknl_assert_lock);
553 	knlist_init(&so->so_wrsel.si_note, so, so_wrknl_lock, so_wrknl_unlock,
554 	    so_wrknl_assert_lock);
555 	if ((prp->pr_flags & PR_SOCKBUF) == 0) {
556 		so->so_snd.sb_mtx = &so->so_snd_mtx;
557 		so->so_rcv.sb_mtx = &so->so_rcv_mtx;
558 	}
559 	/*
560 	 * Auto-sizing of socket buffers is managed by the protocols and
561 	 * the appropriate flags must be set in the pru_attach function.
562 	 */
563 	CURVNET_SET(so->so_vnet);
564 	error = prp->pr_attach(so, proto, td);
565 	CURVNET_RESTORE();
566 	if (error) {
567 		sodealloc(so);
568 		return (error);
569 	}
570 	soref(so);
571 	*aso = so;
572 	return (0);
573 }
574 
575 #ifdef REGRESSION
576 static int regression_sonewconn_earlytest = 1;
577 SYSCTL_INT(_regression, OID_AUTO, sonewconn_earlytest, CTLFLAG_RW,
578     &regression_sonewconn_earlytest, 0, "Perform early sonewconn limit test");
579 #endif
580 
581 static struct timeval overinterval = { 60, 0 };
582 SYSCTL_TIMEVAL_SEC(_kern_ipc, OID_AUTO, sooverinterval, CTLFLAG_RW,
583     &overinterval,
584     "Delay in seconds between warnings for listen socket overflows");
585 
586 /*
587  * When an attempt at a new connection is noted on a socket which supports
588  * accept(2), the protocol has two options:
589  * 1) Call legacy sonewconn() function, which would call protocol attach
590  *    method, same as used for socket(2).
591  * 2) Call solisten_clone(), do attach that is specific to a cloned connection,
592  *    and then call solisten_enqueue().
593  *
594  * Note: the ref count on the socket is 0 on return.
595  */
596 struct socket *
597 solisten_clone(struct socket *head)
598 {
599 	struct sbuf descrsb;
600 	struct socket *so;
601 	int len, overcount;
602 	u_int qlen;
603 	const char localprefix[] = "local:";
604 	char descrbuf[SUNPATHLEN + sizeof(localprefix)];
605 #if defined(INET6)
606 	char addrbuf[INET6_ADDRSTRLEN];
607 #elif defined(INET)
608 	char addrbuf[INET_ADDRSTRLEN];
609 #endif
610 	bool dolog, over;
611 
612 	SOLISTEN_LOCK(head);
613 	over = (head->sol_qlen > 3 * head->sol_qlimit / 2);
614 #ifdef REGRESSION
615 	if (regression_sonewconn_earlytest && over) {
616 #else
617 	if (over) {
618 #endif
619 		head->sol_overcount++;
620 		dolog = !!ratecheck(&head->sol_lastover, &overinterval);
621 
622 		/*
623 		 * If we're going to log, copy the overflow count and queue
624 		 * length from the listen socket before dropping the lock.
625 		 * Also, reset the overflow count.
626 		 */
627 		if (dolog) {
628 			overcount = head->sol_overcount;
629 			head->sol_overcount = 0;
630 			qlen = head->sol_qlen;
631 		}
632 		SOLISTEN_UNLOCK(head);
633 
634 		if (dolog) {
635 			/*
636 			 * Try to print something descriptive about the
637 			 * socket for the error message.
638 			 */
639 			sbuf_new(&descrsb, descrbuf, sizeof(descrbuf),
640 			    SBUF_FIXEDLEN);
641 			switch (head->so_proto->pr_domain->dom_family) {
642 #if defined(INET) || defined(INET6)
643 #ifdef INET
644 			case AF_INET:
645 #endif
646 #ifdef INET6
647 			case AF_INET6:
648 				if (head->so_proto->pr_domain->dom_family ==
649 				    AF_INET6 ||
650 				    (sotoinpcb(head)->inp_inc.inc_flags &
651 				    INC_ISIPV6)) {
652 					ip6_sprintf(addrbuf,
653 					    &sotoinpcb(head)->inp_inc.inc6_laddr);
654 					sbuf_printf(&descrsb, "[%s]", addrbuf);
655 				} else
656 #endif
657 				{
658 #ifdef INET
659 					inet_ntoa_r(
660 					    sotoinpcb(head)->inp_inc.inc_laddr,
661 					    addrbuf);
662 					sbuf_cat(&descrsb, addrbuf);
663 #endif
664 				}
665 				sbuf_printf(&descrsb, ":%hu (proto %u)",
666 				    ntohs(sotoinpcb(head)->inp_inc.inc_lport),
667 				    head->so_proto->pr_protocol);
668 				break;
669 #endif /* INET || INET6 */
670 			case AF_UNIX:
671 				sbuf_cat(&descrsb, localprefix);
672 				if (sotounpcb(head)->unp_addr != NULL)
673 					len =
674 					    sotounpcb(head)->unp_addr->sun_len -
675 					    offsetof(struct sockaddr_un,
676 					    sun_path);
677 				else
678 					len = 0;
679 				if (len > 0)
680 					sbuf_bcat(&descrsb,
681 					    sotounpcb(head)->unp_addr->sun_path,
682 					    len);
683 				else
684 					sbuf_cat(&descrsb, "(unknown)");
685 				break;
686 			}
687 
688 			/*
689 			 * If we can't print something more specific, at least
690 			 * print the domain name.
691 			 */
692 			if (sbuf_finish(&descrsb) != 0 ||
693 			    sbuf_len(&descrsb) <= 0) {
694 				sbuf_clear(&descrsb);
695 				sbuf_cat(&descrsb,
696 				    head->so_proto->pr_domain->dom_name ?:
697 				    "unknown");
698 				sbuf_finish(&descrsb);
699 			}
700 			KASSERT(sbuf_len(&descrsb) > 0,
701 			    ("%s: sbuf creation failed", __func__));
702 			/*
703 			 * Preserve the historic listen queue overflow log
704 			 * message, that starts with "sonewconn:".  It has
705 			 * been known to sysadmins for years and also test
706 			 * sys/kern/sonewconn_overflow checks for it.
707 			 */
708 			if (head->so_cred == 0) {
709 				log(LOG_DEBUG, "sonewconn: pcb %p (%s): "
710 				    "Listen queue overflow: %i already in "
711 				    "queue awaiting acceptance (%d "
712 				    "occurrences)\n", head->so_pcb,
713 				    sbuf_data(&descrsb),
714 			    	qlen, overcount);
715 			} else {
716 				log(LOG_DEBUG, "sonewconn: pcb %p (%s): "
717 				    "Listen queue overflow: "
718 				    "%i already in queue awaiting acceptance "
719 				    "(%d occurrences), euid %d, rgid %d, jail %s\n",
720 				    head->so_pcb, sbuf_data(&descrsb), qlen,
721 				    overcount, head->so_cred->cr_uid,
722 				    head->so_cred->cr_rgid,
723 				    head->so_cred->cr_prison ?
724 					head->so_cred->cr_prison->pr_name :
725 					"not_jailed");
726 			}
727 			sbuf_delete(&descrsb);
728 
729 			overcount = 0;
730 		}
731 
732 		return (NULL);
733 	}
734 	SOLISTEN_UNLOCK(head);
735 	VNET_ASSERT(head->so_vnet != NULL, ("%s: so %p vnet is NULL",
736 	    __func__, head));
737 	so = soalloc(head->so_vnet);
738 	if (so == NULL) {
739 		log(LOG_DEBUG, "%s: pcb %p: New socket allocation failure: "
740 		    "limit reached or out of memory\n",
741 		    __func__, head->so_pcb);
742 		return (NULL);
743 	}
744 	so->so_listen = head;
745 	so->so_type = head->so_type;
746 	so->so_options = head->so_options & ~SO_ACCEPTCONN;
747 	so->so_linger = head->so_linger;
748 	so->so_state = head->so_state;
749 	so->so_fibnum = head->so_fibnum;
750 	so->so_proto = head->so_proto;
751 	so->so_cred = crhold(head->so_cred);
752 #ifdef MAC
753 	mac_socket_newconn(head, so);
754 #endif
755 	knlist_init(&so->so_rdsel.si_note, so, so_rdknl_lock, so_rdknl_unlock,
756 	    so_rdknl_assert_lock);
757 	knlist_init(&so->so_wrsel.si_note, so, so_wrknl_lock, so_wrknl_unlock,
758 	    so_wrknl_assert_lock);
759 	VNET_SO_ASSERT(head);
760 	if (soreserve(so, head->sol_sbsnd_hiwat, head->sol_sbrcv_hiwat)) {
761 		sodealloc(so);
762 		log(LOG_DEBUG, "%s: pcb %p: soreserve() failed\n",
763 		    __func__, head->so_pcb);
764 		return (NULL);
765 	}
766 	so->so_rcv.sb_lowat = head->sol_sbrcv_lowat;
767 	so->so_snd.sb_lowat = head->sol_sbsnd_lowat;
768 	so->so_rcv.sb_timeo = head->sol_sbrcv_timeo;
769 	so->so_snd.sb_timeo = head->sol_sbsnd_timeo;
770 	so->so_rcv.sb_flags = head->sol_sbrcv_flags & SB_AUTOSIZE;
771 	so->so_snd.sb_flags = head->sol_sbsnd_flags & SB_AUTOSIZE;
772 	if ((so->so_proto->pr_flags & PR_SOCKBUF) == 0) {
773 		so->so_snd.sb_mtx = &so->so_snd_mtx;
774 		so->so_rcv.sb_mtx = &so->so_rcv_mtx;
775 	}
776 
777 	return (so);
778 }
779 
780 /* Connstatus may be 0, or SS_ISCONFIRMING, or SS_ISCONNECTED. */
781 struct socket *
782 sonewconn(struct socket *head, int connstatus)
783 {
784 	struct socket *so;
785 
786 	if ((so = solisten_clone(head)) == NULL)
787 		return (NULL);
788 
789 	if (so->so_proto->pr_attach(so, 0, NULL) != 0) {
790 		sodealloc(so);
791 		log(LOG_DEBUG, "%s: pcb %p: pr_attach() failed\n",
792 		    __func__, head->so_pcb);
793 		return (NULL);
794 	}
795 
796 	(void)solisten_enqueue(so, connstatus);
797 
798 	return (so);
799 }
800 
801 /*
802  * Enqueue socket cloned by solisten_clone() to the listen queue of the
803  * listener it has been cloned from.
804  *
805  * Return 'true' if socket landed on complete queue, otherwise 'false'.
806  */
807 bool
808 solisten_enqueue(struct socket *so, int connstatus)
809 {
810 	struct socket *head = so->so_listen;
811 
812 	MPASS(refcount_load(&so->so_count) == 0);
813 	refcount_init(&so->so_count, 1);
814 
815 	SOLISTEN_LOCK(head);
816 	if (head->sol_accept_filter != NULL)
817 		connstatus = 0;
818 	so->so_state |= connstatus;
819 	soref(head); /* A socket on (in)complete queue refs head. */
820 	if (connstatus) {
821 		TAILQ_INSERT_TAIL(&head->sol_comp, so, so_list);
822 		so->so_qstate = SQ_COMP;
823 		head->sol_qlen++;
824 		solisten_wakeup(head);	/* unlocks */
825 		return (true);
826 	} else {
827 		/*
828 		 * Keep removing sockets from the head until there's room for
829 		 * us to insert on the tail.  In pre-locking revisions, this
830 		 * was a simple if(), but as we could be racing with other
831 		 * threads and soabort() requires dropping locks, we must
832 		 * loop waiting for the condition to be true.
833 		 */
834 		while (head->sol_incqlen > head->sol_qlimit) {
835 			struct socket *sp;
836 
837 			sp = TAILQ_FIRST(&head->sol_incomp);
838 			TAILQ_REMOVE(&head->sol_incomp, sp, so_list);
839 			head->sol_incqlen--;
840 			SOCK_LOCK(sp);
841 			sp->so_qstate = SQ_NONE;
842 			sp->so_listen = NULL;
843 			SOCK_UNLOCK(sp);
844 			sorele_locked(head);	/* does SOLISTEN_UNLOCK, head stays */
845 			soabort(sp);
846 			SOLISTEN_LOCK(head);
847 		}
848 		TAILQ_INSERT_TAIL(&head->sol_incomp, so, so_list);
849 		so->so_qstate = SQ_INCOMP;
850 		head->sol_incqlen++;
851 		SOLISTEN_UNLOCK(head);
852 		return (false);
853 	}
854 }
855 
856 #if defined(SCTP) || defined(SCTP_SUPPORT)
857 /*
858  * Socket part of sctp_peeloff().  Detach a new socket from an
859  * association.  The new socket is returned with a reference.
860  *
861  * XXXGL: reduce copy-paste with solisten_clone().
862  */
863 struct socket *
864 sopeeloff(struct socket *head)
865 {
866 	struct socket *so;
867 
868 	VNET_ASSERT(head->so_vnet != NULL, ("%s:%d so_vnet is NULL, head=%p",
869 	    __func__, __LINE__, head));
870 	so = soalloc(head->so_vnet);
871 	if (so == NULL) {
872 		log(LOG_DEBUG, "%s: pcb %p: New socket allocation failure: "
873 		    "limit reached or out of memory\n",
874 		    __func__, head->so_pcb);
875 		return (NULL);
876 	}
877 	so->so_type = head->so_type;
878 	so->so_options = head->so_options;
879 	so->so_linger = head->so_linger;
880 	so->so_state = (head->so_state & SS_NBIO) | SS_ISCONNECTED;
881 	so->so_fibnum = head->so_fibnum;
882 	so->so_proto = head->so_proto;
883 	so->so_cred = crhold(head->so_cred);
884 #ifdef MAC
885 	mac_socket_newconn(head, so);
886 #endif
887 	knlist_init(&so->so_rdsel.si_note, so, so_rdknl_lock, so_rdknl_unlock,
888 	    so_rdknl_assert_lock);
889 	knlist_init(&so->so_wrsel.si_note, so, so_wrknl_lock, so_wrknl_unlock,
890 	    so_wrknl_assert_lock);
891 	VNET_SO_ASSERT(head);
892 	if (soreserve(so, head->so_snd.sb_hiwat, head->so_rcv.sb_hiwat)) {
893 		sodealloc(so);
894 		log(LOG_DEBUG, "%s: pcb %p: soreserve() failed\n",
895 		    __func__, head->so_pcb);
896 		return (NULL);
897 	}
898 	if ((*so->so_proto->pr_attach)(so, 0, NULL)) {
899 		sodealloc(so);
900 		log(LOG_DEBUG, "%s: pcb %p: pru_attach() failed\n",
901 		    __func__, head->so_pcb);
902 		return (NULL);
903 	}
904 	so->so_rcv.sb_lowat = head->so_rcv.sb_lowat;
905 	so->so_snd.sb_lowat = head->so_snd.sb_lowat;
906 	so->so_rcv.sb_timeo = head->so_rcv.sb_timeo;
907 	so->so_snd.sb_timeo = head->so_snd.sb_timeo;
908 	so->so_rcv.sb_flags |= head->so_rcv.sb_flags & SB_AUTOSIZE;
909 	so->so_snd.sb_flags |= head->so_snd.sb_flags & SB_AUTOSIZE;
910 
911 	soref(so);
912 
913 	return (so);
914 }
915 #endif	/* SCTP */
916 
917 int
918 sobind(struct socket *so, struct sockaddr *nam, struct thread *td)
919 {
920 	int error;
921 
922 	CURVNET_SET(so->so_vnet);
923 	error = so->so_proto->pr_bind(so, nam, td);
924 	CURVNET_RESTORE();
925 	return (error);
926 }
927 
928 int
929 sobindat(int fd, struct socket *so, struct sockaddr *nam, struct thread *td)
930 {
931 	int error;
932 
933 	CURVNET_SET(so->so_vnet);
934 	error = so->so_proto->pr_bindat(fd, so, nam, td);
935 	CURVNET_RESTORE();
936 	return (error);
937 }
938 
939 /*
940  * solisten() transitions a socket from a non-listening state to a listening
941  * state, but can also be used to update the listen queue depth on an
942  * existing listen socket.  The protocol will call back into the sockets
943  * layer using solisten_proto_check() and solisten_proto() to check and set
944  * socket-layer listen state.  Call backs are used so that the protocol can
945  * acquire both protocol and socket layer locks in whatever order is required
946  * by the protocol.
947  *
948  * Protocol implementors are advised to hold the socket lock across the
949  * socket-layer test and set to avoid races at the socket layer.
950  */
951 int
952 solisten(struct socket *so, int backlog, struct thread *td)
953 {
954 	int error;
955 
956 	CURVNET_SET(so->so_vnet);
957 	error = so->so_proto->pr_listen(so, backlog, td);
958 	CURVNET_RESTORE();
959 	return (error);
960 }
961 
962 /*
963  * Prepare for a call to solisten_proto().  Acquire all socket buffer locks in
964  * order to interlock with socket I/O.
965  */
966 int
967 solisten_proto_check(struct socket *so)
968 {
969 	SOCK_LOCK_ASSERT(so);
970 
971 	if ((so->so_state & (SS_ISCONNECTED | SS_ISCONNECTING |
972 	    SS_ISDISCONNECTING)) != 0)
973 		return (EINVAL);
974 
975 	/*
976 	 * Sleeping is not permitted here, so simply fail if userspace is
977 	 * attempting to transmit or receive on the socket.  This kind of
978 	 * transient failure is not ideal, but it should occur only if userspace
979 	 * is misusing the socket interfaces.
980 	 */
981 	if (!sx_try_xlock(&so->so_snd_sx))
982 		return (EAGAIN);
983 	if (!sx_try_xlock(&so->so_rcv_sx)) {
984 		sx_xunlock(&so->so_snd_sx);
985 		return (EAGAIN);
986 	}
987 	mtx_lock(&so->so_snd_mtx);
988 	mtx_lock(&so->so_rcv_mtx);
989 
990 	/* Interlock with soo_aio_queue() and KTLS. */
991 	if (!SOLISTENING(so)) {
992 		bool ktls;
993 
994 #ifdef KERN_TLS
995 		ktls = so->so_snd.sb_tls_info != NULL ||
996 		    so->so_rcv.sb_tls_info != NULL;
997 #else
998 		ktls = false;
999 #endif
1000 		if (ktls ||
1001 		    (so->so_snd.sb_flags & (SB_AIO | SB_AIO_RUNNING)) != 0 ||
1002 		    (so->so_rcv.sb_flags & (SB_AIO | SB_AIO_RUNNING)) != 0) {
1003 			solisten_proto_abort(so);
1004 			return (EINVAL);
1005 		}
1006 	}
1007 
1008 	return (0);
1009 }
1010 
1011 /*
1012  * Undo the setup done by solisten_proto_check().
1013  */
1014 void
1015 solisten_proto_abort(struct socket *so)
1016 {
1017 	mtx_unlock(&so->so_snd_mtx);
1018 	mtx_unlock(&so->so_rcv_mtx);
1019 	sx_xunlock(&so->so_snd_sx);
1020 	sx_xunlock(&so->so_rcv_sx);
1021 }
1022 
1023 void
1024 solisten_proto(struct socket *so, int backlog)
1025 {
1026 	int sbrcv_lowat, sbsnd_lowat;
1027 	u_int sbrcv_hiwat, sbsnd_hiwat;
1028 	short sbrcv_flags, sbsnd_flags;
1029 	sbintime_t sbrcv_timeo, sbsnd_timeo;
1030 
1031 	SOCK_LOCK_ASSERT(so);
1032 	KASSERT((so->so_state & (SS_ISCONNECTED | SS_ISCONNECTING |
1033 	    SS_ISDISCONNECTING)) == 0,
1034 	    ("%s: bad socket state %p", __func__, so));
1035 
1036 	if (SOLISTENING(so))
1037 		goto listening;
1038 
1039 	/*
1040 	 * Change this socket to listening state.
1041 	 */
1042 	sbrcv_lowat = so->so_rcv.sb_lowat;
1043 	sbsnd_lowat = so->so_snd.sb_lowat;
1044 	sbrcv_hiwat = so->so_rcv.sb_hiwat;
1045 	sbsnd_hiwat = so->so_snd.sb_hiwat;
1046 	sbrcv_flags = so->so_rcv.sb_flags;
1047 	sbsnd_flags = so->so_snd.sb_flags;
1048 	sbrcv_timeo = so->so_rcv.sb_timeo;
1049 	sbsnd_timeo = so->so_snd.sb_timeo;
1050 
1051 	sbdestroy(so, SO_SND);
1052 	sbdestroy(so, SO_RCV);
1053 
1054 #ifdef INVARIANTS
1055 	bzero(&so->so_rcv,
1056 	    sizeof(struct socket) - offsetof(struct socket, so_rcv));
1057 #endif
1058 
1059 	so->sol_sbrcv_lowat = sbrcv_lowat;
1060 	so->sol_sbsnd_lowat = sbsnd_lowat;
1061 	so->sol_sbrcv_hiwat = sbrcv_hiwat;
1062 	so->sol_sbsnd_hiwat = sbsnd_hiwat;
1063 	so->sol_sbrcv_flags = sbrcv_flags;
1064 	so->sol_sbsnd_flags = sbsnd_flags;
1065 	so->sol_sbrcv_timeo = sbrcv_timeo;
1066 	so->sol_sbsnd_timeo = sbsnd_timeo;
1067 
1068 	so->sol_qlen = so->sol_incqlen = 0;
1069 	TAILQ_INIT(&so->sol_incomp);
1070 	TAILQ_INIT(&so->sol_comp);
1071 
1072 	so->sol_accept_filter = NULL;
1073 	so->sol_accept_filter_arg = NULL;
1074 	so->sol_accept_filter_str = NULL;
1075 
1076 	so->sol_upcall = NULL;
1077 	so->sol_upcallarg = NULL;
1078 
1079 	so->so_options |= SO_ACCEPTCONN;
1080 
1081 listening:
1082 	if (backlog < 0 || backlog > somaxconn)
1083 		backlog = somaxconn;
1084 	so->sol_qlimit = backlog;
1085 
1086 	mtx_unlock(&so->so_snd_mtx);
1087 	mtx_unlock(&so->so_rcv_mtx);
1088 	sx_xunlock(&so->so_snd_sx);
1089 	sx_xunlock(&so->so_rcv_sx);
1090 }
1091 
1092 /*
1093  * Wakeup listeners/subsystems once we have a complete connection.
1094  * Enters with lock, returns unlocked.
1095  */
1096 void
1097 solisten_wakeup(struct socket *sol)
1098 {
1099 
1100 	if (sol->sol_upcall != NULL)
1101 		(void )sol->sol_upcall(sol, sol->sol_upcallarg, M_NOWAIT);
1102 	else {
1103 		selwakeuppri(&sol->so_rdsel, PSOCK);
1104 		KNOTE_LOCKED(&sol->so_rdsel.si_note, 0);
1105 	}
1106 	SOLISTEN_UNLOCK(sol);
1107 	wakeup_one(&sol->sol_comp);
1108 	if ((sol->so_state & SS_ASYNC) && sol->so_sigio != NULL)
1109 		pgsigio(&sol->so_sigio, SIGIO, 0);
1110 }
1111 
1112 /*
1113  * Return single connection off a listening socket queue.  Main consumer of
1114  * the function is kern_accept4().  Some modules, that do their own accept
1115  * management also use the function.  The socket reference held by the
1116  * listen queue is handed to the caller.
1117  *
1118  * Listening socket must be locked on entry and is returned unlocked on
1119  * return.
1120  * The flags argument is set of accept4(2) flags and ACCEPT4_INHERIT.
1121  */
1122 int
1123 solisten_dequeue(struct socket *head, struct socket **ret, int flags)
1124 {
1125 	struct socket *so;
1126 	int error;
1127 
1128 	SOLISTEN_LOCK_ASSERT(head);
1129 
1130 	while (!(head->so_state & SS_NBIO) && TAILQ_EMPTY(&head->sol_comp) &&
1131 	    head->so_error == 0) {
1132 		error = msleep(&head->sol_comp, SOCK_MTX(head), PSOCK | PCATCH,
1133 		    "accept", 0);
1134 		if (error != 0) {
1135 			SOLISTEN_UNLOCK(head);
1136 			return (error);
1137 		}
1138 	}
1139 	if (head->so_error) {
1140 		error = head->so_error;
1141 		head->so_error = 0;
1142 	} else if ((head->so_state & SS_NBIO) && TAILQ_EMPTY(&head->sol_comp))
1143 		error = EWOULDBLOCK;
1144 	else
1145 		error = 0;
1146 	if (error) {
1147 		SOLISTEN_UNLOCK(head);
1148 		return (error);
1149 	}
1150 	so = TAILQ_FIRST(&head->sol_comp);
1151 	SOCK_LOCK(so);
1152 	KASSERT(so->so_qstate == SQ_COMP,
1153 	    ("%s: so %p not SQ_COMP", __func__, so));
1154 	head->sol_qlen--;
1155 	so->so_qstate = SQ_NONE;
1156 	so->so_listen = NULL;
1157 	TAILQ_REMOVE(&head->sol_comp, so, so_list);
1158 	if (flags & ACCEPT4_INHERIT)
1159 		so->so_state |= (head->so_state & SS_NBIO);
1160 	else
1161 		so->so_state |= (flags & SOCK_NONBLOCK) ? SS_NBIO : 0;
1162 	SOCK_UNLOCK(so);
1163 	sorele_locked(head);
1164 
1165 	*ret = so;
1166 	return (0);
1167 }
1168 
1169 /*
1170  * Free socket upon release of the very last reference.
1171  */
1172 static void
1173 sofree(struct socket *so)
1174 {
1175 	struct protosw *pr = so->so_proto;
1176 
1177 	SOCK_LOCK_ASSERT(so);
1178 	KASSERT(refcount_load(&so->so_count) == 0,
1179 	    ("%s: so %p has references", __func__, so));
1180 	KASSERT(SOLISTENING(so) || so->so_qstate == SQ_NONE,
1181 	    ("%s: so %p is on listen queue", __func__, so));
1182 
1183 	SOCK_UNLOCK(so);
1184 
1185 	if (so->so_dtor != NULL)
1186 		so->so_dtor(so);
1187 
1188 	VNET_SO_ASSERT(so);
1189 	if ((pr->pr_flags & PR_RIGHTS) && !SOLISTENING(so)) {
1190 		MPASS(pr->pr_domain->dom_dispose != NULL);
1191 		(*pr->pr_domain->dom_dispose)(so);
1192 	}
1193 	if (pr->pr_detach != NULL)
1194 		pr->pr_detach(so);
1195 
1196 	/*
1197 	 * From this point on, we assume that no other references to this
1198 	 * socket exist anywhere else in the stack.  Therefore, no locks need
1199 	 * to be acquired or held.
1200 	 */
1201 	if (!(pr->pr_flags & PR_SOCKBUF) && !SOLISTENING(so)) {
1202 		sbdestroy(so, SO_SND);
1203 		sbdestroy(so, SO_RCV);
1204 	}
1205 	seldrain(&so->so_rdsel);
1206 	seldrain(&so->so_wrsel);
1207 	knlist_destroy(&so->so_rdsel.si_note);
1208 	knlist_destroy(&so->so_wrsel.si_note);
1209 	sodealloc(so);
1210 }
1211 
1212 /*
1213  * Release a reference on a socket while holding the socket lock.
1214  * Unlocks the socket lock before returning.
1215  */
1216 void
1217 sorele_locked(struct socket *so)
1218 {
1219 	SOCK_LOCK_ASSERT(so);
1220 	if (refcount_release(&so->so_count))
1221 		sofree(so);
1222 	else
1223 		SOCK_UNLOCK(so);
1224 }
1225 
1226 /*
1227  * Close a socket on last file table reference removal.  Initiate disconnect
1228  * if connected.  Free socket when disconnect complete.
1229  *
1230  * This function will sorele() the socket.  Note that soclose() may be called
1231  * prior to the ref count reaching zero.  The actual socket structure will
1232  * not be freed until the ref count reaches zero.
1233  */
1234 int
1235 soclose(struct socket *so)
1236 {
1237 	struct accept_queue lqueue;
1238 	int error = 0;
1239 	bool listening, last __diagused;
1240 
1241 	CURVNET_SET(so->so_vnet);
1242 	funsetown(&so->so_sigio);
1243 	if (so->so_state & SS_ISCONNECTED) {
1244 		if ((so->so_state & SS_ISDISCONNECTING) == 0) {
1245 			error = sodisconnect(so);
1246 			if (error) {
1247 				if (error == ENOTCONN)
1248 					error = 0;
1249 				goto drop;
1250 			}
1251 		}
1252 
1253 		if ((so->so_options & SO_LINGER) != 0 && so->so_linger != 0) {
1254 			if ((so->so_state & SS_ISDISCONNECTING) &&
1255 			    (so->so_state & SS_NBIO))
1256 				goto drop;
1257 			while (so->so_state & SS_ISCONNECTED) {
1258 				error = tsleep(&so->so_timeo,
1259 				    PSOCK | PCATCH, "soclos",
1260 				    so->so_linger * hz);
1261 				if (error)
1262 					break;
1263 			}
1264 		}
1265 	}
1266 
1267 drop:
1268 	if (so->so_proto->pr_close != NULL)
1269 		so->so_proto->pr_close(so);
1270 
1271 	SOCK_LOCK(so);
1272 	if ((listening = SOLISTENING(so))) {
1273 		struct socket *sp;
1274 
1275 		TAILQ_INIT(&lqueue);
1276 		TAILQ_SWAP(&lqueue, &so->sol_incomp, socket, so_list);
1277 		TAILQ_CONCAT(&lqueue, &so->sol_comp, so_list);
1278 
1279 		so->sol_qlen = so->sol_incqlen = 0;
1280 
1281 		TAILQ_FOREACH(sp, &lqueue, so_list) {
1282 			SOCK_LOCK(sp);
1283 			sp->so_qstate = SQ_NONE;
1284 			sp->so_listen = NULL;
1285 			SOCK_UNLOCK(sp);
1286 			last = refcount_release(&so->so_count);
1287 			KASSERT(!last, ("%s: released last reference for %p",
1288 			    __func__, so));
1289 		}
1290 	}
1291 	sorele_locked(so);
1292 	if (listening) {
1293 		struct socket *sp, *tsp;
1294 
1295 		TAILQ_FOREACH_SAFE(sp, &lqueue, so_list, tsp)
1296 			soabort(sp);
1297 	}
1298 	CURVNET_RESTORE();
1299 	return (error);
1300 }
1301 
1302 /*
1303  * soabort() is used to abruptly tear down a connection, such as when a
1304  * resource limit is reached (listen queue depth exceeded), or if a listen
1305  * socket is closed while there are sockets waiting to be accepted.
1306  *
1307  * This interface is tricky, because it is called on an unreferenced socket,
1308  * and must be called only by a thread that has actually removed the socket
1309  * from the listen queue it was on.  Likely this thread holds the last
1310  * reference on the socket and soabort() will proceed with sofree().  But
1311  * it might be not the last, as the sockets on the listen queues are seen
1312  * from the protocol side.
1313  *
1314  * This interface will call into the protocol code, so must not be called
1315  * with any socket locks held.  Protocols do call it while holding their own
1316  * recursible protocol mutexes, but this is something that should be subject
1317  * to review in the future.
1318  *
1319  * Usually socket should have a single reference left, but this is not a
1320  * requirement.  In the past, when we have had named references for file
1321  * descriptor and protocol, we asserted that none of them are being held.
1322  */
1323 void
1324 soabort(struct socket *so)
1325 {
1326 
1327 	VNET_SO_ASSERT(so);
1328 
1329 	if (so->so_proto->pr_abort != NULL)
1330 		so->so_proto->pr_abort(so);
1331 	SOCK_LOCK(so);
1332 	sorele_locked(so);
1333 }
1334 
1335 int
1336 soaccept(struct socket *so, struct sockaddr **nam)
1337 {
1338 	int error;
1339 
1340 	CURVNET_SET(so->so_vnet);
1341 	error = so->so_proto->pr_accept(so, nam);
1342 	CURVNET_RESTORE();
1343 	return (error);
1344 }
1345 
1346 int
1347 soconnect(struct socket *so, struct sockaddr *nam, struct thread *td)
1348 {
1349 
1350 	return (soconnectat(AT_FDCWD, so, nam, td));
1351 }
1352 
1353 int
1354 soconnectat(int fd, struct socket *so, struct sockaddr *nam, struct thread *td)
1355 {
1356 	int error;
1357 
1358 	CURVNET_SET(so->so_vnet);
1359 
1360 	/*
1361 	 * If protocol is connection-based, can only connect once.
1362 	 * Otherwise, if connected, try to disconnect first.  This allows
1363 	 * user to disconnect by connecting to, e.g., a null address.
1364 	 *
1365 	 * Note, this check is racy and may need to be re-evaluated at the
1366 	 * protocol layer.
1367 	 */
1368 	if (so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING) &&
1369 	    ((so->so_proto->pr_flags & PR_CONNREQUIRED) ||
1370 	    (error = sodisconnect(so)))) {
1371 		error = EISCONN;
1372 	} else {
1373 		/*
1374 		 * Prevent accumulated error from previous connection from
1375 		 * biting us.
1376 		 */
1377 		so->so_error = 0;
1378 		if (fd == AT_FDCWD) {
1379 			error = so->so_proto->pr_connect(so, nam, td);
1380 		} else {
1381 			error = so->so_proto->pr_connectat(fd, so, nam, td);
1382 		}
1383 	}
1384 	CURVNET_RESTORE();
1385 
1386 	return (error);
1387 }
1388 
1389 int
1390 soconnect2(struct socket *so1, struct socket *so2)
1391 {
1392 	int error;
1393 
1394 	CURVNET_SET(so1->so_vnet);
1395 	error = so1->so_proto->pr_connect2(so1, so2);
1396 	CURVNET_RESTORE();
1397 	return (error);
1398 }
1399 
1400 int
1401 sodisconnect(struct socket *so)
1402 {
1403 	int error;
1404 
1405 	if ((so->so_state & SS_ISCONNECTED) == 0)
1406 		return (ENOTCONN);
1407 	if (so->so_state & SS_ISDISCONNECTING)
1408 		return (EALREADY);
1409 	VNET_SO_ASSERT(so);
1410 	error = so->so_proto->pr_disconnect(so);
1411 	return (error);
1412 }
1413 
1414 int
1415 sosend_dgram(struct socket *so, struct sockaddr *addr, struct uio *uio,
1416     struct mbuf *top, struct mbuf *control, int flags, struct thread *td)
1417 {
1418 	long space;
1419 	ssize_t resid;
1420 	int clen = 0, error, dontroute;
1421 
1422 	KASSERT(so->so_type == SOCK_DGRAM, ("sosend_dgram: !SOCK_DGRAM"));
1423 	KASSERT(so->so_proto->pr_flags & PR_ATOMIC,
1424 	    ("sosend_dgram: !PR_ATOMIC"));
1425 
1426 	if (uio != NULL)
1427 		resid = uio->uio_resid;
1428 	else
1429 		resid = top->m_pkthdr.len;
1430 	/*
1431 	 * In theory resid should be unsigned.  However, space must be
1432 	 * signed, as it might be less than 0 if we over-committed, and we
1433 	 * must use a signed comparison of space and resid.  On the other
1434 	 * hand, a negative resid causes us to loop sending 0-length
1435 	 * segments to the protocol.
1436 	 */
1437 	if (resid < 0) {
1438 		error = EINVAL;
1439 		goto out;
1440 	}
1441 
1442 	dontroute =
1443 	    (flags & MSG_DONTROUTE) && (so->so_options & SO_DONTROUTE) == 0;
1444 	if (td != NULL)
1445 		td->td_ru.ru_msgsnd++;
1446 	if (control != NULL)
1447 		clen = control->m_len;
1448 
1449 	SOCKBUF_LOCK(&so->so_snd);
1450 	if (so->so_snd.sb_state & SBS_CANTSENDMORE) {
1451 		SOCKBUF_UNLOCK(&so->so_snd);
1452 		error = EPIPE;
1453 		goto out;
1454 	}
1455 	if (so->so_error) {
1456 		error = so->so_error;
1457 		so->so_error = 0;
1458 		SOCKBUF_UNLOCK(&so->so_snd);
1459 		goto out;
1460 	}
1461 	if ((so->so_state & SS_ISCONNECTED) == 0) {
1462 		/*
1463 		 * `sendto' and `sendmsg' is allowed on a connection-based
1464 		 * socket if it supports implied connect.  Return ENOTCONN if
1465 		 * not connected and no address is supplied.
1466 		 */
1467 		if ((so->so_proto->pr_flags & PR_CONNREQUIRED) &&
1468 		    (so->so_proto->pr_flags & PR_IMPLOPCL) == 0) {
1469 			if ((so->so_state & SS_ISCONFIRMING) == 0 &&
1470 			    !(resid == 0 && clen != 0)) {
1471 				SOCKBUF_UNLOCK(&so->so_snd);
1472 				error = ENOTCONN;
1473 				goto out;
1474 			}
1475 		} else if (addr == NULL) {
1476 			if (so->so_proto->pr_flags & PR_CONNREQUIRED)
1477 				error = ENOTCONN;
1478 			else
1479 				error = EDESTADDRREQ;
1480 			SOCKBUF_UNLOCK(&so->so_snd);
1481 			goto out;
1482 		}
1483 	}
1484 
1485 	/*
1486 	 * Do we need MSG_OOB support in SOCK_DGRAM?  Signs here may be a
1487 	 * problem and need fixing.
1488 	 */
1489 	space = sbspace(&so->so_snd);
1490 	if (flags & MSG_OOB)
1491 		space += 1024;
1492 	space -= clen;
1493 	SOCKBUF_UNLOCK(&so->so_snd);
1494 	if (resid > space) {
1495 		error = EMSGSIZE;
1496 		goto out;
1497 	}
1498 	if (uio == NULL) {
1499 		resid = 0;
1500 		if (flags & MSG_EOR)
1501 			top->m_flags |= M_EOR;
1502 	} else {
1503 		/*
1504 		 * Copy the data from userland into a mbuf chain.
1505 		 * If no data is to be copied in, a single empty mbuf
1506 		 * is returned.
1507 		 */
1508 		top = m_uiotombuf(uio, M_WAITOK, space, max_hdr,
1509 		    (M_PKTHDR | ((flags & MSG_EOR) ? M_EOR : 0)));
1510 		if (top == NULL) {
1511 			error = EFAULT;	/* only possible error */
1512 			goto out;
1513 		}
1514 		space -= resid - uio->uio_resid;
1515 		resid = uio->uio_resid;
1516 	}
1517 	KASSERT(resid == 0, ("sosend_dgram: resid != 0"));
1518 	/*
1519 	 * XXXRW: Frobbing SO_DONTROUTE here is even worse without sblock
1520 	 * than with.
1521 	 */
1522 	if (dontroute) {
1523 		SOCK_LOCK(so);
1524 		so->so_options |= SO_DONTROUTE;
1525 		SOCK_UNLOCK(so);
1526 	}
1527 	/*
1528 	 * XXX all the SBS_CANTSENDMORE checks previously done could be out
1529 	 * of date.  We could have received a reset packet in an interrupt or
1530 	 * maybe we slept while doing page faults in uiomove() etc.  We could
1531 	 * probably recheck again inside the locking protection here, but
1532 	 * there are probably other places that this also happens.  We must
1533 	 * rethink this.
1534 	 */
1535 	VNET_SO_ASSERT(so);
1536 	error = so->so_proto->pr_send(so, (flags & MSG_OOB) ? PRUS_OOB :
1537 	/*
1538 	 * If the user set MSG_EOF, the protocol understands this flag and
1539 	 * nothing left to send then use PRU_SEND_EOF instead of PRU_SEND.
1540 	 */
1541 	    ((flags & MSG_EOF) &&
1542 	     (so->so_proto->pr_flags & PR_IMPLOPCL) &&
1543 	     (resid <= 0)) ?
1544 		PRUS_EOF :
1545 		/* If there is more to send set PRUS_MORETOCOME */
1546 		(flags & MSG_MORETOCOME) ||
1547 		(resid > 0 && space > 0) ? PRUS_MORETOCOME : 0,
1548 		top, addr, control, td);
1549 	if (dontroute) {
1550 		SOCK_LOCK(so);
1551 		so->so_options &= ~SO_DONTROUTE;
1552 		SOCK_UNLOCK(so);
1553 	}
1554 	clen = 0;
1555 	control = NULL;
1556 	top = NULL;
1557 out:
1558 	if (top != NULL)
1559 		m_freem(top);
1560 	if (control != NULL)
1561 		m_freem(control);
1562 	return (error);
1563 }
1564 
1565 /*
1566  * Send on a socket.  If send must go all at once and message is larger than
1567  * send buffering, then hard error.  Lock against other senders.  If must go
1568  * all at once and not enough room now, then inform user that this would
1569  * block and do nothing.  Otherwise, if nonblocking, send as much as
1570  * possible.  The data to be sent is described by "uio" if nonzero, otherwise
1571  * by the mbuf chain "top" (which must be null if uio is not).  Data provided
1572  * in mbuf chain must be small enough to send all at once.
1573  *
1574  * Returns nonzero on error, timeout or signal; callers must check for short
1575  * counts if EINTR/ERESTART are returned.  Data and control buffers are freed
1576  * on return.
1577  */
1578 int
1579 sosend_generic(struct socket *so, struct sockaddr *addr, struct uio *uio,
1580     struct mbuf *top, struct mbuf *control, int flags, struct thread *td)
1581 {
1582 	long space;
1583 	ssize_t resid;
1584 	int clen = 0, error, dontroute;
1585 	int atomic = sosendallatonce(so) || top;
1586 	int pr_send_flag;
1587 #ifdef KERN_TLS
1588 	struct ktls_session *tls;
1589 	int tls_enq_cnt, tls_send_flag;
1590 	uint8_t tls_rtype;
1591 
1592 	tls = NULL;
1593 	tls_rtype = TLS_RLTYPE_APP;
1594 #endif
1595 	if (uio != NULL)
1596 		resid = uio->uio_resid;
1597 	else if ((top->m_flags & M_PKTHDR) != 0)
1598 		resid = top->m_pkthdr.len;
1599 	else
1600 		resid = m_length(top, NULL);
1601 	/*
1602 	 * In theory resid should be unsigned.  However, space must be
1603 	 * signed, as it might be less than 0 if we over-committed, and we
1604 	 * must use a signed comparison of space and resid.  On the other
1605 	 * hand, a negative resid causes us to loop sending 0-length
1606 	 * segments to the protocol.
1607 	 *
1608 	 * Also check to make sure that MSG_EOR isn't used on SOCK_STREAM
1609 	 * type sockets since that's an error.
1610 	 */
1611 	if (resid < 0 || (so->so_type == SOCK_STREAM && (flags & MSG_EOR))) {
1612 		error = EINVAL;
1613 		goto out;
1614 	}
1615 
1616 	dontroute =
1617 	    (flags & MSG_DONTROUTE) && (so->so_options & SO_DONTROUTE) == 0 &&
1618 	    (so->so_proto->pr_flags & PR_ATOMIC);
1619 	if (td != NULL)
1620 		td->td_ru.ru_msgsnd++;
1621 	if (control != NULL)
1622 		clen = control->m_len;
1623 
1624 	error = SOCK_IO_SEND_LOCK(so, SBLOCKWAIT(flags));
1625 	if (error)
1626 		goto out;
1627 
1628 #ifdef KERN_TLS
1629 	tls_send_flag = 0;
1630 	tls = ktls_hold(so->so_snd.sb_tls_info);
1631 	if (tls != NULL) {
1632 		if (tls->mode == TCP_TLS_MODE_SW)
1633 			tls_send_flag = PRUS_NOTREADY;
1634 
1635 		if (control != NULL) {
1636 			struct cmsghdr *cm = mtod(control, struct cmsghdr *);
1637 
1638 			if (clen >= sizeof(*cm) &&
1639 			    cm->cmsg_type == TLS_SET_RECORD_TYPE) {
1640 				tls_rtype = *((uint8_t *)CMSG_DATA(cm));
1641 				clen = 0;
1642 				m_freem(control);
1643 				control = NULL;
1644 				atomic = 1;
1645 			}
1646 		}
1647 
1648 		if (resid == 0 && !ktls_permit_empty_frames(tls)) {
1649 			error = EINVAL;
1650 			goto release;
1651 		}
1652 	}
1653 #endif
1654 
1655 restart:
1656 	do {
1657 		SOCKBUF_LOCK(&so->so_snd);
1658 		if (so->so_snd.sb_state & SBS_CANTSENDMORE) {
1659 			SOCKBUF_UNLOCK(&so->so_snd);
1660 			error = EPIPE;
1661 			goto release;
1662 		}
1663 		if (so->so_error) {
1664 			error = so->so_error;
1665 			so->so_error = 0;
1666 			SOCKBUF_UNLOCK(&so->so_snd);
1667 			goto release;
1668 		}
1669 		if ((so->so_state & SS_ISCONNECTED) == 0) {
1670 			/*
1671 			 * `sendto' and `sendmsg' is allowed on a connection-
1672 			 * based socket if it supports implied connect.
1673 			 * Return ENOTCONN if not connected and no address is
1674 			 * supplied.
1675 			 */
1676 			if ((so->so_proto->pr_flags & PR_CONNREQUIRED) &&
1677 			    (so->so_proto->pr_flags & PR_IMPLOPCL) == 0) {
1678 				if ((so->so_state & SS_ISCONFIRMING) == 0 &&
1679 				    !(resid == 0 && clen != 0)) {
1680 					SOCKBUF_UNLOCK(&so->so_snd);
1681 					error = ENOTCONN;
1682 					goto release;
1683 				}
1684 			} else if (addr == NULL) {
1685 				SOCKBUF_UNLOCK(&so->so_snd);
1686 				if (so->so_proto->pr_flags & PR_CONNREQUIRED)
1687 					error = ENOTCONN;
1688 				else
1689 					error = EDESTADDRREQ;
1690 				goto release;
1691 			}
1692 		}
1693 		space = sbspace(&so->so_snd);
1694 		if (flags & MSG_OOB)
1695 			space += 1024;
1696 		if ((atomic && resid > so->so_snd.sb_hiwat) ||
1697 		    clen > so->so_snd.sb_hiwat) {
1698 			SOCKBUF_UNLOCK(&so->so_snd);
1699 			error = EMSGSIZE;
1700 			goto release;
1701 		}
1702 		if (space < resid + clen &&
1703 		    (atomic || space < so->so_snd.sb_lowat || space < clen)) {
1704 			if ((so->so_state & SS_NBIO) ||
1705 			    (flags & (MSG_NBIO | MSG_DONTWAIT)) != 0) {
1706 				SOCKBUF_UNLOCK(&so->so_snd);
1707 				error = EWOULDBLOCK;
1708 				goto release;
1709 			}
1710 			error = sbwait(so, SO_SND);
1711 			SOCKBUF_UNLOCK(&so->so_snd);
1712 			if (error)
1713 				goto release;
1714 			goto restart;
1715 		}
1716 		SOCKBUF_UNLOCK(&so->so_snd);
1717 		space -= clen;
1718 		do {
1719 			if (uio == NULL) {
1720 				resid = 0;
1721 				if (flags & MSG_EOR)
1722 					top->m_flags |= M_EOR;
1723 #ifdef KERN_TLS
1724 				if (tls != NULL) {
1725 					ktls_frame(top, tls, &tls_enq_cnt,
1726 					    tls_rtype);
1727 					tls_rtype = TLS_RLTYPE_APP;
1728 				}
1729 #endif
1730 			} else {
1731 				/*
1732 				 * Copy the data from userland into a mbuf
1733 				 * chain.  If resid is 0, which can happen
1734 				 * only if we have control to send, then
1735 				 * a single empty mbuf is returned.  This
1736 				 * is a workaround to prevent protocol send
1737 				 * methods to panic.
1738 				 */
1739 #ifdef KERN_TLS
1740 				if (tls != NULL) {
1741 					top = m_uiotombuf(uio, M_WAITOK, space,
1742 					    tls->params.max_frame_len,
1743 					    M_EXTPG |
1744 					    ((flags & MSG_EOR) ? M_EOR : 0));
1745 					if (top != NULL) {
1746 						ktls_frame(top, tls,
1747 						    &tls_enq_cnt, tls_rtype);
1748 					}
1749 					tls_rtype = TLS_RLTYPE_APP;
1750 				} else
1751 #endif
1752 					top = m_uiotombuf(uio, M_WAITOK, space,
1753 					    (atomic ? max_hdr : 0),
1754 					    (atomic ? M_PKTHDR : 0) |
1755 					    ((flags & MSG_EOR) ? M_EOR : 0));
1756 				if (top == NULL) {
1757 					error = EFAULT; /* only possible error */
1758 					goto release;
1759 				}
1760 				space -= resid - uio->uio_resid;
1761 				resid = uio->uio_resid;
1762 			}
1763 			if (dontroute) {
1764 				SOCK_LOCK(so);
1765 				so->so_options |= SO_DONTROUTE;
1766 				SOCK_UNLOCK(so);
1767 			}
1768 			/*
1769 			 * XXX all the SBS_CANTSENDMORE checks previously
1770 			 * done could be out of date.  We could have received
1771 			 * a reset packet in an interrupt or maybe we slept
1772 			 * while doing page faults in uiomove() etc.  We
1773 			 * could probably recheck again inside the locking
1774 			 * protection here, but there are probably other
1775 			 * places that this also happens.  We must rethink
1776 			 * this.
1777 			 */
1778 			VNET_SO_ASSERT(so);
1779 
1780 			pr_send_flag = (flags & MSG_OOB) ? PRUS_OOB :
1781 			/*
1782 			 * If the user set MSG_EOF, the protocol understands
1783 			 * this flag and nothing left to send then use
1784 			 * PRU_SEND_EOF instead of PRU_SEND.
1785 			 */
1786 			    ((flags & MSG_EOF) &&
1787 			     (so->so_proto->pr_flags & PR_IMPLOPCL) &&
1788 			     (resid <= 0)) ?
1789 				PRUS_EOF :
1790 			/* If there is more to send set PRUS_MORETOCOME. */
1791 			    (flags & MSG_MORETOCOME) ||
1792 			    (resid > 0 && space > 0) ? PRUS_MORETOCOME : 0;
1793 
1794 #ifdef KERN_TLS
1795 			pr_send_flag |= tls_send_flag;
1796 #endif
1797 
1798 			error = so->so_proto->pr_send(so, pr_send_flag, top,
1799 			    addr, control, td);
1800 
1801 			if (dontroute) {
1802 				SOCK_LOCK(so);
1803 				so->so_options &= ~SO_DONTROUTE;
1804 				SOCK_UNLOCK(so);
1805 			}
1806 
1807 #ifdef KERN_TLS
1808 			if (tls != NULL && tls->mode == TCP_TLS_MODE_SW) {
1809 				if (error != 0) {
1810 					m_freem(top);
1811 					top = NULL;
1812 				} else {
1813 					soref(so);
1814 					ktls_enqueue(top, so, tls_enq_cnt);
1815 				}
1816 			}
1817 #endif
1818 			clen = 0;
1819 			control = NULL;
1820 			top = NULL;
1821 			if (error)
1822 				goto release;
1823 		} while (resid && space > 0);
1824 	} while (resid);
1825 
1826 release:
1827 	SOCK_IO_SEND_UNLOCK(so);
1828 out:
1829 #ifdef KERN_TLS
1830 	if (tls != NULL)
1831 		ktls_free(tls);
1832 #endif
1833 	if (top != NULL)
1834 		m_freem(top);
1835 	if (control != NULL)
1836 		m_freem(control);
1837 	return (error);
1838 }
1839 
1840 /*
1841  * Send to a socket from a kernel thread.
1842  *
1843  * XXXGL: in almost all cases uio is NULL and the mbuf is supplied.
1844  * Exception is nfs/bootp_subr.c.  It is arguable that the VNET context needs
1845  * to be set at all.  This function should just boil down to a static inline
1846  * calling the protocol method.
1847  */
1848 int
1849 sosend(struct socket *so, struct sockaddr *addr, struct uio *uio,
1850     struct mbuf *top, struct mbuf *control, int flags, struct thread *td)
1851 {
1852 	int error;
1853 
1854 	CURVNET_SET(so->so_vnet);
1855 	error = so->so_proto->pr_sosend(so, addr, uio,
1856 	    top, control, flags, td);
1857 	CURVNET_RESTORE();
1858 	return (error);
1859 }
1860 
1861 /*
1862  * send(2), write(2) or aio_write(2) on a socket.
1863  */
1864 int
1865 sousrsend(struct socket *so, struct sockaddr *addr, struct uio *uio,
1866     struct mbuf *control, int flags, struct proc *userproc)
1867 {
1868 	struct thread *td;
1869 	ssize_t len;
1870 	int error;
1871 
1872 	td = uio->uio_td;
1873 	len = uio->uio_resid;
1874 	CURVNET_SET(so->so_vnet);
1875 	error = so->so_proto->pr_sosend(so, addr, uio, NULL, control, flags,
1876 	    td);
1877 	CURVNET_RESTORE();
1878 	if (error != 0) {
1879 		/*
1880 		 * Clear transient errors for stream protocols if they made
1881 		 * some progress.  Make exclusion for aio(4) that would
1882 		 * schedule a new write in case of EWOULDBLOCK and clear
1883 		 * error itself.  See soaio_process_job().
1884 		 */
1885 		if (uio->uio_resid != len &&
1886 		    (so->so_proto->pr_flags & PR_ATOMIC) == 0 &&
1887 		    userproc == NULL &&
1888 		    (error == ERESTART || error == EINTR ||
1889 		    error == EWOULDBLOCK))
1890 			error = 0;
1891 		/* Generation of SIGPIPE can be controlled per socket. */
1892 		if (error == EPIPE && (so->so_options & SO_NOSIGPIPE) == 0 &&
1893 		    (flags & MSG_NOSIGNAL) == 0) {
1894 			if (userproc != NULL) {
1895 				/* aio(4) job */
1896 				PROC_LOCK(userproc);
1897 				kern_psignal(userproc, SIGPIPE);
1898 				PROC_UNLOCK(userproc);
1899 			} else {
1900 				PROC_LOCK(td->td_proc);
1901 				tdsignal(td, SIGPIPE);
1902 				PROC_UNLOCK(td->td_proc);
1903 			}
1904 		}
1905 	}
1906 	return (error);
1907 }
1908 
1909 /*
1910  * The part of soreceive() that implements reading non-inline out-of-band
1911  * data from a socket.  For more complete comments, see soreceive(), from
1912  * which this code originated.
1913  *
1914  * Note that soreceive_rcvoob(), unlike the remainder of soreceive(), is
1915  * unable to return an mbuf chain to the caller.
1916  */
1917 static int
1918 soreceive_rcvoob(struct socket *so, struct uio *uio, int flags)
1919 {
1920 	struct protosw *pr = so->so_proto;
1921 	struct mbuf *m;
1922 	int error;
1923 
1924 	KASSERT(flags & MSG_OOB, ("soreceive_rcvoob: (flags & MSG_OOB) == 0"));
1925 	VNET_SO_ASSERT(so);
1926 
1927 	m = m_get(M_WAITOK, MT_DATA);
1928 	error = pr->pr_rcvoob(so, m, flags & MSG_PEEK);
1929 	if (error)
1930 		goto bad;
1931 	do {
1932 		error = uiomove(mtod(m, void *),
1933 		    (int) min(uio->uio_resid, m->m_len), uio);
1934 		m = m_free(m);
1935 	} while (uio->uio_resid && error == 0 && m);
1936 bad:
1937 	if (m != NULL)
1938 		m_freem(m);
1939 	return (error);
1940 }
1941 
1942 /*
1943  * Following replacement or removal of the first mbuf on the first mbuf chain
1944  * of a socket buffer, push necessary state changes back into the socket
1945  * buffer so that other consumers see the values consistently.  'nextrecord'
1946  * is the callers locally stored value of the original value of
1947  * sb->sb_mb->m_nextpkt which must be restored when the lead mbuf changes.
1948  * NOTE: 'nextrecord' may be NULL.
1949  */
1950 static __inline void
1951 sockbuf_pushsync(struct sockbuf *sb, struct mbuf *nextrecord)
1952 {
1953 
1954 	SOCKBUF_LOCK_ASSERT(sb);
1955 	/*
1956 	 * First, update for the new value of nextrecord.  If necessary, make
1957 	 * it the first record.
1958 	 */
1959 	if (sb->sb_mb != NULL)
1960 		sb->sb_mb->m_nextpkt = nextrecord;
1961 	else
1962 		sb->sb_mb = nextrecord;
1963 
1964 	/*
1965 	 * Now update any dependent socket buffer fields to reflect the new
1966 	 * state.  This is an expanded inline of SB_EMPTY_FIXUP(), with the
1967 	 * addition of a second clause that takes care of the case where
1968 	 * sb_mb has been updated, but remains the last record.
1969 	 */
1970 	if (sb->sb_mb == NULL) {
1971 		sb->sb_mbtail = NULL;
1972 		sb->sb_lastrecord = NULL;
1973 	} else if (sb->sb_mb->m_nextpkt == NULL)
1974 		sb->sb_lastrecord = sb->sb_mb;
1975 }
1976 
1977 /*
1978  * Implement receive operations on a socket.  We depend on the way that
1979  * records are added to the sockbuf by sbappend.  In particular, each record
1980  * (mbufs linked through m_next) must begin with an address if the protocol
1981  * so specifies, followed by an optional mbuf or mbufs containing ancillary
1982  * data, and then zero or more mbufs of data.  In order to allow parallelism
1983  * between network receive and copying to user space, as well as avoid
1984  * sleeping with a mutex held, we release the socket buffer mutex during the
1985  * user space copy.  Although the sockbuf is locked, new data may still be
1986  * appended, and thus we must maintain consistency of the sockbuf during that
1987  * time.
1988  *
1989  * The caller may receive the data as a single mbuf chain by supplying an
1990  * mbuf **mp0 for use in returning the chain.  The uio is then used only for
1991  * the count in uio_resid.
1992  */
1993 int
1994 soreceive_generic(struct socket *so, struct sockaddr **psa, struct uio *uio,
1995     struct mbuf **mp0, struct mbuf **controlp, int *flagsp)
1996 {
1997 	struct mbuf *m, **mp;
1998 	int flags, error, offset;
1999 	ssize_t len;
2000 	struct protosw *pr = so->so_proto;
2001 	struct mbuf *nextrecord;
2002 	int moff, type = 0;
2003 	ssize_t orig_resid = uio->uio_resid;
2004 	bool report_real_len = false;
2005 
2006 	mp = mp0;
2007 	if (psa != NULL)
2008 		*psa = NULL;
2009 	if (controlp != NULL)
2010 		*controlp = NULL;
2011 	if (flagsp != NULL) {
2012 		report_real_len = *flagsp & MSG_TRUNC;
2013 		*flagsp &= ~MSG_TRUNC;
2014 		flags = *flagsp &~ MSG_EOR;
2015 	} else
2016 		flags = 0;
2017 	if (flags & MSG_OOB)
2018 		return (soreceive_rcvoob(so, uio, flags));
2019 	if (mp != NULL)
2020 		*mp = NULL;
2021 	if ((pr->pr_flags & PR_WANTRCVD) && (so->so_state & SS_ISCONFIRMING)
2022 	    && uio->uio_resid) {
2023 		VNET_SO_ASSERT(so);
2024 		pr->pr_rcvd(so, 0);
2025 	}
2026 
2027 	error = SOCK_IO_RECV_LOCK(so, SBLOCKWAIT(flags));
2028 	if (error)
2029 		return (error);
2030 
2031 restart:
2032 	SOCKBUF_LOCK(&so->so_rcv);
2033 	m = so->so_rcv.sb_mb;
2034 	/*
2035 	 * If we have less data than requested, block awaiting more (subject
2036 	 * to any timeout) if:
2037 	 *   1. the current count is less than the low water mark, or
2038 	 *   2. MSG_DONTWAIT is not set
2039 	 */
2040 	if (m == NULL || (((flags & MSG_DONTWAIT) == 0 &&
2041 	    sbavail(&so->so_rcv) < uio->uio_resid) &&
2042 	    sbavail(&so->so_rcv) < so->so_rcv.sb_lowat &&
2043 	    m->m_nextpkt == NULL && (pr->pr_flags & PR_ATOMIC) == 0)) {
2044 		KASSERT(m != NULL || !sbavail(&so->so_rcv),
2045 		    ("receive: m == %p sbavail == %u",
2046 		    m, sbavail(&so->so_rcv)));
2047 		if (so->so_error || so->so_rerror) {
2048 			if (m != NULL)
2049 				goto dontblock;
2050 			if (so->so_error)
2051 				error = so->so_error;
2052 			else
2053 				error = so->so_rerror;
2054 			if ((flags & MSG_PEEK) == 0) {
2055 				if (so->so_error)
2056 					so->so_error = 0;
2057 				else
2058 					so->so_rerror = 0;
2059 			}
2060 			SOCKBUF_UNLOCK(&so->so_rcv);
2061 			goto release;
2062 		}
2063 		SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2064 		if (so->so_rcv.sb_state & SBS_CANTRCVMORE) {
2065 			if (m != NULL)
2066 				goto dontblock;
2067 #ifdef KERN_TLS
2068 			else if (so->so_rcv.sb_tlsdcc == 0 &&
2069 			    so->so_rcv.sb_tlscc == 0) {
2070 #else
2071 			else {
2072 #endif
2073 				SOCKBUF_UNLOCK(&so->so_rcv);
2074 				goto release;
2075 			}
2076 		}
2077 		for (; m != NULL; m = m->m_next)
2078 			if (m->m_type == MT_OOBDATA  || (m->m_flags & M_EOR)) {
2079 				m = so->so_rcv.sb_mb;
2080 				goto dontblock;
2081 			}
2082 		if ((so->so_state & (SS_ISCONNECTING | SS_ISCONNECTED |
2083 		    SS_ISDISCONNECTING | SS_ISDISCONNECTED)) == 0 &&
2084 		    (so->so_proto->pr_flags & PR_CONNREQUIRED) != 0) {
2085 			SOCKBUF_UNLOCK(&so->so_rcv);
2086 			error = ENOTCONN;
2087 			goto release;
2088 		}
2089 		if (uio->uio_resid == 0 && !report_real_len) {
2090 			SOCKBUF_UNLOCK(&so->so_rcv);
2091 			goto release;
2092 		}
2093 		if ((so->so_state & SS_NBIO) ||
2094 		    (flags & (MSG_DONTWAIT|MSG_NBIO))) {
2095 			SOCKBUF_UNLOCK(&so->so_rcv);
2096 			error = EWOULDBLOCK;
2097 			goto release;
2098 		}
2099 		SBLASTRECORDCHK(&so->so_rcv);
2100 		SBLASTMBUFCHK(&so->so_rcv);
2101 		error = sbwait(so, SO_RCV);
2102 		SOCKBUF_UNLOCK(&so->so_rcv);
2103 		if (error)
2104 			goto release;
2105 		goto restart;
2106 	}
2107 dontblock:
2108 	/*
2109 	 * From this point onward, we maintain 'nextrecord' as a cache of the
2110 	 * pointer to the next record in the socket buffer.  We must keep the
2111 	 * various socket buffer pointers and local stack versions of the
2112 	 * pointers in sync, pushing out modifications before dropping the
2113 	 * socket buffer mutex, and re-reading them when picking it up.
2114 	 *
2115 	 * Otherwise, we will race with the network stack appending new data
2116 	 * or records onto the socket buffer by using inconsistent/stale
2117 	 * versions of the field, possibly resulting in socket buffer
2118 	 * corruption.
2119 	 *
2120 	 * By holding the high-level sblock(), we prevent simultaneous
2121 	 * readers from pulling off the front of the socket buffer.
2122 	 */
2123 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2124 	if (uio->uio_td)
2125 		uio->uio_td->td_ru.ru_msgrcv++;
2126 	KASSERT(m == so->so_rcv.sb_mb, ("soreceive: m != so->so_rcv.sb_mb"));
2127 	SBLASTRECORDCHK(&so->so_rcv);
2128 	SBLASTMBUFCHK(&so->so_rcv);
2129 	nextrecord = m->m_nextpkt;
2130 	if (pr->pr_flags & PR_ADDR) {
2131 		KASSERT(m->m_type == MT_SONAME,
2132 		    ("m->m_type == %d", m->m_type));
2133 		orig_resid = 0;
2134 		if (psa != NULL)
2135 			*psa = sodupsockaddr(mtod(m, struct sockaddr *),
2136 			    M_NOWAIT);
2137 		if (flags & MSG_PEEK) {
2138 			m = m->m_next;
2139 		} else {
2140 			sbfree(&so->so_rcv, m);
2141 			so->so_rcv.sb_mb = m_free(m);
2142 			m = so->so_rcv.sb_mb;
2143 			sockbuf_pushsync(&so->so_rcv, nextrecord);
2144 		}
2145 	}
2146 
2147 	/*
2148 	 * Process one or more MT_CONTROL mbufs present before any data mbufs
2149 	 * in the first mbuf chain on the socket buffer.  If MSG_PEEK, we
2150 	 * just copy the data; if !MSG_PEEK, we call into the protocol to
2151 	 * perform externalization (or freeing if controlp == NULL).
2152 	 */
2153 	if (m != NULL && m->m_type == MT_CONTROL) {
2154 		struct mbuf *cm = NULL, *cmn;
2155 		struct mbuf **cme = &cm;
2156 #ifdef KERN_TLS
2157 		struct cmsghdr *cmsg;
2158 		struct tls_get_record tgr;
2159 
2160 		/*
2161 		 * For MSG_TLSAPPDATA, check for an alert record.
2162 		 * If found, return ENXIO without removing
2163 		 * it from the receive queue.  This allows a subsequent
2164 		 * call without MSG_TLSAPPDATA to receive it.
2165 		 * Note that, for TLS, there should only be a single
2166 		 * control mbuf with the TLS_GET_RECORD message in it.
2167 		 */
2168 		if (flags & MSG_TLSAPPDATA) {
2169 			cmsg = mtod(m, struct cmsghdr *);
2170 			if (cmsg->cmsg_type == TLS_GET_RECORD &&
2171 			    cmsg->cmsg_len == CMSG_LEN(sizeof(tgr))) {
2172 				memcpy(&tgr, CMSG_DATA(cmsg), sizeof(tgr));
2173 				if (__predict_false(tgr.tls_type ==
2174 				    TLS_RLTYPE_ALERT)) {
2175 					SOCKBUF_UNLOCK(&so->so_rcv);
2176 					error = ENXIO;
2177 					goto release;
2178 				}
2179 			}
2180 		}
2181 #endif
2182 
2183 		do {
2184 			if (flags & MSG_PEEK) {
2185 				if (controlp != NULL) {
2186 					*controlp = m_copym(m, 0, m->m_len,
2187 					    M_NOWAIT);
2188 					controlp = &(*controlp)->m_next;
2189 				}
2190 				m = m->m_next;
2191 			} else {
2192 				sbfree(&so->so_rcv, m);
2193 				so->so_rcv.sb_mb = m->m_next;
2194 				m->m_next = NULL;
2195 				*cme = m;
2196 				cme = &(*cme)->m_next;
2197 				m = so->so_rcv.sb_mb;
2198 			}
2199 		} while (m != NULL && m->m_type == MT_CONTROL);
2200 		if ((flags & MSG_PEEK) == 0)
2201 			sockbuf_pushsync(&so->so_rcv, nextrecord);
2202 		while (cm != NULL) {
2203 			cmn = cm->m_next;
2204 			cm->m_next = NULL;
2205 			if (pr->pr_domain->dom_externalize != NULL) {
2206 				SOCKBUF_UNLOCK(&so->so_rcv);
2207 				VNET_SO_ASSERT(so);
2208 				error = (*pr->pr_domain->dom_externalize)
2209 				    (cm, controlp, flags);
2210 				SOCKBUF_LOCK(&so->so_rcv);
2211 			} else if (controlp != NULL)
2212 				*controlp = cm;
2213 			else
2214 				m_freem(cm);
2215 			if (controlp != NULL) {
2216 				while (*controlp != NULL)
2217 					controlp = &(*controlp)->m_next;
2218 			}
2219 			cm = cmn;
2220 		}
2221 		if (m != NULL)
2222 			nextrecord = so->so_rcv.sb_mb->m_nextpkt;
2223 		else
2224 			nextrecord = so->so_rcv.sb_mb;
2225 		orig_resid = 0;
2226 	}
2227 	if (m != NULL) {
2228 		if ((flags & MSG_PEEK) == 0) {
2229 			KASSERT(m->m_nextpkt == nextrecord,
2230 			    ("soreceive: post-control, nextrecord !sync"));
2231 			if (nextrecord == NULL) {
2232 				KASSERT(so->so_rcv.sb_mb == m,
2233 				    ("soreceive: post-control, sb_mb!=m"));
2234 				KASSERT(so->so_rcv.sb_lastrecord == m,
2235 				    ("soreceive: post-control, lastrecord!=m"));
2236 			}
2237 		}
2238 		type = m->m_type;
2239 		if (type == MT_OOBDATA)
2240 			flags |= MSG_OOB;
2241 	} else {
2242 		if ((flags & MSG_PEEK) == 0) {
2243 			KASSERT(so->so_rcv.sb_mb == nextrecord,
2244 			    ("soreceive: sb_mb != nextrecord"));
2245 			if (so->so_rcv.sb_mb == NULL) {
2246 				KASSERT(so->so_rcv.sb_lastrecord == NULL,
2247 				    ("soreceive: sb_lastercord != NULL"));
2248 			}
2249 		}
2250 	}
2251 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2252 	SBLASTRECORDCHK(&so->so_rcv);
2253 	SBLASTMBUFCHK(&so->so_rcv);
2254 
2255 	/*
2256 	 * Now continue to read any data mbufs off of the head of the socket
2257 	 * buffer until the read request is satisfied.  Note that 'type' is
2258 	 * used to store the type of any mbuf reads that have happened so far
2259 	 * such that soreceive() can stop reading if the type changes, which
2260 	 * causes soreceive() to return only one of regular data and inline
2261 	 * out-of-band data in a single socket receive operation.
2262 	 */
2263 	moff = 0;
2264 	offset = 0;
2265 	while (m != NULL && !(m->m_flags & M_NOTAVAIL) && uio->uio_resid > 0
2266 	    && error == 0) {
2267 		/*
2268 		 * If the type of mbuf has changed since the last mbuf
2269 		 * examined ('type'), end the receive operation.
2270 		 */
2271 		SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2272 		if (m->m_type == MT_OOBDATA || m->m_type == MT_CONTROL) {
2273 			if (type != m->m_type)
2274 				break;
2275 		} else if (type == MT_OOBDATA)
2276 			break;
2277 		else
2278 		    KASSERT(m->m_type == MT_DATA,
2279 			("m->m_type == %d", m->m_type));
2280 		so->so_rcv.sb_state &= ~SBS_RCVATMARK;
2281 		len = uio->uio_resid;
2282 		if (so->so_oobmark && len > so->so_oobmark - offset)
2283 			len = so->so_oobmark - offset;
2284 		if (len > m->m_len - moff)
2285 			len = m->m_len - moff;
2286 		/*
2287 		 * If mp is set, just pass back the mbufs.  Otherwise copy
2288 		 * them out via the uio, then free.  Sockbuf must be
2289 		 * consistent here (points to current mbuf, it points to next
2290 		 * record) when we drop priority; we must note any additions
2291 		 * to the sockbuf when we block interrupts again.
2292 		 */
2293 		if (mp == NULL) {
2294 			SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2295 			SBLASTRECORDCHK(&so->so_rcv);
2296 			SBLASTMBUFCHK(&so->so_rcv);
2297 			SOCKBUF_UNLOCK(&so->so_rcv);
2298 			if ((m->m_flags & M_EXTPG) != 0)
2299 				error = m_unmapped_uiomove(m, moff, uio,
2300 				    (int)len);
2301 			else
2302 				error = uiomove(mtod(m, char *) + moff,
2303 				    (int)len, uio);
2304 			SOCKBUF_LOCK(&so->so_rcv);
2305 			if (error) {
2306 				/*
2307 				 * The MT_SONAME mbuf has already been removed
2308 				 * from the record, so it is necessary to
2309 				 * remove the data mbufs, if any, to preserve
2310 				 * the invariant in the case of PR_ADDR that
2311 				 * requires MT_SONAME mbufs at the head of
2312 				 * each record.
2313 				 */
2314 				if (pr->pr_flags & PR_ATOMIC &&
2315 				    ((flags & MSG_PEEK) == 0))
2316 					(void)sbdroprecord_locked(&so->so_rcv);
2317 				SOCKBUF_UNLOCK(&so->so_rcv);
2318 				goto release;
2319 			}
2320 		} else
2321 			uio->uio_resid -= len;
2322 		SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2323 		if (len == m->m_len - moff) {
2324 			if (m->m_flags & M_EOR)
2325 				flags |= MSG_EOR;
2326 			if (flags & MSG_PEEK) {
2327 				m = m->m_next;
2328 				moff = 0;
2329 			} else {
2330 				nextrecord = m->m_nextpkt;
2331 				sbfree(&so->so_rcv, m);
2332 				if (mp != NULL) {
2333 					m->m_nextpkt = NULL;
2334 					*mp = m;
2335 					mp = &m->m_next;
2336 					so->so_rcv.sb_mb = m = m->m_next;
2337 					*mp = NULL;
2338 				} else {
2339 					so->so_rcv.sb_mb = m_free(m);
2340 					m = so->so_rcv.sb_mb;
2341 				}
2342 				sockbuf_pushsync(&so->so_rcv, nextrecord);
2343 				SBLASTRECORDCHK(&so->so_rcv);
2344 				SBLASTMBUFCHK(&so->so_rcv);
2345 			}
2346 		} else {
2347 			if (flags & MSG_PEEK)
2348 				moff += len;
2349 			else {
2350 				if (mp != NULL) {
2351 					if (flags & MSG_DONTWAIT) {
2352 						*mp = m_copym(m, 0, len,
2353 						    M_NOWAIT);
2354 						if (*mp == NULL) {
2355 							/*
2356 							 * m_copym() couldn't
2357 							 * allocate an mbuf.
2358 							 * Adjust uio_resid back
2359 							 * (it was adjusted
2360 							 * down by len bytes,
2361 							 * which we didn't end
2362 							 * up "copying" over).
2363 							 */
2364 							uio->uio_resid += len;
2365 							break;
2366 						}
2367 					} else {
2368 						SOCKBUF_UNLOCK(&so->so_rcv);
2369 						*mp = m_copym(m, 0, len,
2370 						    M_WAITOK);
2371 						SOCKBUF_LOCK(&so->so_rcv);
2372 					}
2373 				}
2374 				sbcut_locked(&so->so_rcv, len);
2375 			}
2376 		}
2377 		SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2378 		if (so->so_oobmark) {
2379 			if ((flags & MSG_PEEK) == 0) {
2380 				so->so_oobmark -= len;
2381 				if (so->so_oobmark == 0) {
2382 					so->so_rcv.sb_state |= SBS_RCVATMARK;
2383 					break;
2384 				}
2385 			} else {
2386 				offset += len;
2387 				if (offset == so->so_oobmark)
2388 					break;
2389 			}
2390 		}
2391 		if (flags & MSG_EOR)
2392 			break;
2393 		/*
2394 		 * If the MSG_WAITALL flag is set (for non-atomic socket), we
2395 		 * must not quit until "uio->uio_resid == 0" or an error
2396 		 * termination.  If a signal/timeout occurs, return with a
2397 		 * short count but without error.  Keep sockbuf locked
2398 		 * against other readers.
2399 		 */
2400 		while (flags & MSG_WAITALL && m == NULL && uio->uio_resid > 0 &&
2401 		    !sosendallatonce(so) && nextrecord == NULL) {
2402 			SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2403 			if (so->so_error || so->so_rerror ||
2404 			    so->so_rcv.sb_state & SBS_CANTRCVMORE)
2405 				break;
2406 			/*
2407 			 * Notify the protocol that some data has been
2408 			 * drained before blocking.
2409 			 */
2410 			if (pr->pr_flags & PR_WANTRCVD) {
2411 				SOCKBUF_UNLOCK(&so->so_rcv);
2412 				VNET_SO_ASSERT(so);
2413 				pr->pr_rcvd(so, flags);
2414 				SOCKBUF_LOCK(&so->so_rcv);
2415 			}
2416 			SBLASTRECORDCHK(&so->so_rcv);
2417 			SBLASTMBUFCHK(&so->so_rcv);
2418 			/*
2419 			 * We could receive some data while was notifying
2420 			 * the protocol. Skip blocking in this case.
2421 			 */
2422 			if (so->so_rcv.sb_mb == NULL) {
2423 				error = sbwait(so, SO_RCV);
2424 				if (error) {
2425 					SOCKBUF_UNLOCK(&so->so_rcv);
2426 					goto release;
2427 				}
2428 			}
2429 			m = so->so_rcv.sb_mb;
2430 			if (m != NULL)
2431 				nextrecord = m->m_nextpkt;
2432 		}
2433 	}
2434 
2435 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2436 	if (m != NULL && pr->pr_flags & PR_ATOMIC) {
2437 		if (report_real_len)
2438 			uio->uio_resid -= m_length(m, NULL) - moff;
2439 		flags |= MSG_TRUNC;
2440 		if ((flags & MSG_PEEK) == 0)
2441 			(void) sbdroprecord_locked(&so->so_rcv);
2442 	}
2443 	if ((flags & MSG_PEEK) == 0) {
2444 		if (m == NULL) {
2445 			/*
2446 			 * First part is an inline SB_EMPTY_FIXUP().  Second
2447 			 * part makes sure sb_lastrecord is up-to-date if
2448 			 * there is still data in the socket buffer.
2449 			 */
2450 			so->so_rcv.sb_mb = nextrecord;
2451 			if (so->so_rcv.sb_mb == NULL) {
2452 				so->so_rcv.sb_mbtail = NULL;
2453 				so->so_rcv.sb_lastrecord = NULL;
2454 			} else if (nextrecord->m_nextpkt == NULL)
2455 				so->so_rcv.sb_lastrecord = nextrecord;
2456 		}
2457 		SBLASTRECORDCHK(&so->so_rcv);
2458 		SBLASTMBUFCHK(&so->so_rcv);
2459 		/*
2460 		 * If soreceive() is being done from the socket callback,
2461 		 * then don't need to generate ACK to peer to update window,
2462 		 * since ACK will be generated on return to TCP.
2463 		 */
2464 		if (!(flags & MSG_SOCALLBCK) &&
2465 		    (pr->pr_flags & PR_WANTRCVD)) {
2466 			SOCKBUF_UNLOCK(&so->so_rcv);
2467 			VNET_SO_ASSERT(so);
2468 			pr->pr_rcvd(so, flags);
2469 			SOCKBUF_LOCK(&so->so_rcv);
2470 		}
2471 	}
2472 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2473 	if (orig_resid == uio->uio_resid && orig_resid &&
2474 	    (flags & MSG_EOR) == 0 && (so->so_rcv.sb_state & SBS_CANTRCVMORE) == 0) {
2475 		SOCKBUF_UNLOCK(&so->so_rcv);
2476 		goto restart;
2477 	}
2478 	SOCKBUF_UNLOCK(&so->so_rcv);
2479 
2480 	if (flagsp != NULL)
2481 		*flagsp |= flags;
2482 release:
2483 	SOCK_IO_RECV_UNLOCK(so);
2484 	return (error);
2485 }
2486 
2487 /*
2488  * Optimized version of soreceive() for stream (TCP) sockets.
2489  */
2490 int
2491 soreceive_stream(struct socket *so, struct sockaddr **psa, struct uio *uio,
2492     struct mbuf **mp0, struct mbuf **controlp, int *flagsp)
2493 {
2494 	int len = 0, error = 0, flags, oresid;
2495 	struct sockbuf *sb;
2496 	struct mbuf *m, *n = NULL;
2497 
2498 	/* We only do stream sockets. */
2499 	if (so->so_type != SOCK_STREAM)
2500 		return (EINVAL);
2501 	if (psa != NULL)
2502 		*psa = NULL;
2503 	if (flagsp != NULL)
2504 		flags = *flagsp &~ MSG_EOR;
2505 	else
2506 		flags = 0;
2507 	if (controlp != NULL)
2508 		*controlp = NULL;
2509 	if (flags & MSG_OOB)
2510 		return (soreceive_rcvoob(so, uio, flags));
2511 	if (mp0 != NULL)
2512 		*mp0 = NULL;
2513 
2514 	sb = &so->so_rcv;
2515 
2516 #ifdef KERN_TLS
2517 	/*
2518 	 * KTLS store TLS records as records with a control message to
2519 	 * describe the framing.
2520 	 *
2521 	 * We check once here before acquiring locks to optimize the
2522 	 * common case.
2523 	 */
2524 	if (sb->sb_tls_info != NULL)
2525 		return (soreceive_generic(so, psa, uio, mp0, controlp,
2526 		    flagsp));
2527 #endif
2528 
2529 	/* Prevent other readers from entering the socket. */
2530 	error = SOCK_IO_RECV_LOCK(so, SBLOCKWAIT(flags));
2531 	if (error)
2532 		return (error);
2533 	SOCKBUF_LOCK(sb);
2534 
2535 #ifdef KERN_TLS
2536 	if (sb->sb_tls_info != NULL) {
2537 		SOCKBUF_UNLOCK(sb);
2538 		SOCK_IO_RECV_UNLOCK(so);
2539 		return (soreceive_generic(so, psa, uio, mp0, controlp,
2540 		    flagsp));
2541 	}
2542 #endif
2543 
2544 	/* Easy one, no space to copyout anything. */
2545 	if (uio->uio_resid == 0) {
2546 		error = EINVAL;
2547 		goto out;
2548 	}
2549 	oresid = uio->uio_resid;
2550 
2551 	/* We will never ever get anything unless we are or were connected. */
2552 	if (!(so->so_state & (SS_ISCONNECTED|SS_ISDISCONNECTED))) {
2553 		error = ENOTCONN;
2554 		goto out;
2555 	}
2556 
2557 restart:
2558 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2559 
2560 	/* Abort if socket has reported problems. */
2561 	if (so->so_error) {
2562 		if (sbavail(sb) > 0)
2563 			goto deliver;
2564 		if (oresid > uio->uio_resid)
2565 			goto out;
2566 		error = so->so_error;
2567 		if (!(flags & MSG_PEEK))
2568 			so->so_error = 0;
2569 		goto out;
2570 	}
2571 
2572 	/* Door is closed.  Deliver what is left, if any. */
2573 	if (sb->sb_state & SBS_CANTRCVMORE) {
2574 		if (sbavail(sb) > 0)
2575 			goto deliver;
2576 		else
2577 			goto out;
2578 	}
2579 
2580 	/* Socket buffer is empty and we shall not block. */
2581 	if (sbavail(sb) == 0 &&
2582 	    ((so->so_state & SS_NBIO) || (flags & (MSG_DONTWAIT|MSG_NBIO)))) {
2583 		error = EAGAIN;
2584 		goto out;
2585 	}
2586 
2587 	/* Socket buffer got some data that we shall deliver now. */
2588 	if (sbavail(sb) > 0 && !(flags & MSG_WAITALL) &&
2589 	    ((so->so_state & SS_NBIO) ||
2590 	     (flags & (MSG_DONTWAIT|MSG_NBIO)) ||
2591 	     sbavail(sb) >= sb->sb_lowat ||
2592 	     sbavail(sb) >= uio->uio_resid ||
2593 	     sbavail(sb) >= sb->sb_hiwat) ) {
2594 		goto deliver;
2595 	}
2596 
2597 	/* On MSG_WAITALL we must wait until all data or error arrives. */
2598 	if ((flags & MSG_WAITALL) &&
2599 	    (sbavail(sb) >= uio->uio_resid || sbavail(sb) >= sb->sb_hiwat))
2600 		goto deliver;
2601 
2602 	/*
2603 	 * Wait and block until (more) data comes in.
2604 	 * NB: Drops the sockbuf lock during wait.
2605 	 */
2606 	error = sbwait(so, SO_RCV);
2607 	if (error)
2608 		goto out;
2609 	goto restart;
2610 
2611 deliver:
2612 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2613 	KASSERT(sbavail(sb) > 0, ("%s: sockbuf empty", __func__));
2614 	KASSERT(sb->sb_mb != NULL, ("%s: sb_mb == NULL", __func__));
2615 
2616 	/* Statistics. */
2617 	if (uio->uio_td)
2618 		uio->uio_td->td_ru.ru_msgrcv++;
2619 
2620 	/* Fill uio until full or current end of socket buffer is reached. */
2621 	len = min(uio->uio_resid, sbavail(sb));
2622 	if (mp0 != NULL) {
2623 		/* Dequeue as many mbufs as possible. */
2624 		if (!(flags & MSG_PEEK) && len >= sb->sb_mb->m_len) {
2625 			if (*mp0 == NULL)
2626 				*mp0 = sb->sb_mb;
2627 			else
2628 				m_cat(*mp0, sb->sb_mb);
2629 			for (m = sb->sb_mb;
2630 			     m != NULL && m->m_len <= len;
2631 			     m = m->m_next) {
2632 				KASSERT(!(m->m_flags & M_NOTAVAIL),
2633 				    ("%s: m %p not available", __func__, m));
2634 				len -= m->m_len;
2635 				uio->uio_resid -= m->m_len;
2636 				sbfree(sb, m);
2637 				n = m;
2638 			}
2639 			n->m_next = NULL;
2640 			sb->sb_mb = m;
2641 			sb->sb_lastrecord = sb->sb_mb;
2642 			if (sb->sb_mb == NULL)
2643 				SB_EMPTY_FIXUP(sb);
2644 		}
2645 		/* Copy the remainder. */
2646 		if (len > 0) {
2647 			KASSERT(sb->sb_mb != NULL,
2648 			    ("%s: len > 0 && sb->sb_mb empty", __func__));
2649 
2650 			m = m_copym(sb->sb_mb, 0, len, M_NOWAIT);
2651 			if (m == NULL)
2652 				len = 0;	/* Don't flush data from sockbuf. */
2653 			else
2654 				uio->uio_resid -= len;
2655 			if (*mp0 != NULL)
2656 				m_cat(*mp0, m);
2657 			else
2658 				*mp0 = m;
2659 			if (*mp0 == NULL) {
2660 				error = ENOBUFS;
2661 				goto out;
2662 			}
2663 		}
2664 	} else {
2665 		/* NB: Must unlock socket buffer as uiomove may sleep. */
2666 		SOCKBUF_UNLOCK(sb);
2667 		error = m_mbuftouio(uio, sb->sb_mb, len);
2668 		SOCKBUF_LOCK(sb);
2669 		if (error)
2670 			goto out;
2671 	}
2672 	SBLASTRECORDCHK(sb);
2673 	SBLASTMBUFCHK(sb);
2674 
2675 	/*
2676 	 * Remove the delivered data from the socket buffer unless we
2677 	 * were only peeking.
2678 	 */
2679 	if (!(flags & MSG_PEEK)) {
2680 		if (len > 0)
2681 			sbdrop_locked(sb, len);
2682 
2683 		/* Notify protocol that we drained some data. */
2684 		if ((so->so_proto->pr_flags & PR_WANTRCVD) &&
2685 		    (((flags & MSG_WAITALL) && uio->uio_resid > 0) ||
2686 		     !(flags & MSG_SOCALLBCK))) {
2687 			SOCKBUF_UNLOCK(sb);
2688 			VNET_SO_ASSERT(so);
2689 			so->so_proto->pr_rcvd(so, flags);
2690 			SOCKBUF_LOCK(sb);
2691 		}
2692 	}
2693 
2694 	/*
2695 	 * For MSG_WAITALL we may have to loop again and wait for
2696 	 * more data to come in.
2697 	 */
2698 	if ((flags & MSG_WAITALL) && uio->uio_resid > 0)
2699 		goto restart;
2700 out:
2701 	SBLASTRECORDCHK(sb);
2702 	SBLASTMBUFCHK(sb);
2703 	SOCKBUF_UNLOCK(sb);
2704 	SOCK_IO_RECV_UNLOCK(so);
2705 	return (error);
2706 }
2707 
2708 /*
2709  * Optimized version of soreceive() for simple datagram cases from userspace.
2710  * Unlike in the stream case, we're able to drop a datagram if copyout()
2711  * fails, and because we handle datagrams atomically, we don't need to use a
2712  * sleep lock to prevent I/O interlacing.
2713  */
2714 int
2715 soreceive_dgram(struct socket *so, struct sockaddr **psa, struct uio *uio,
2716     struct mbuf **mp0, struct mbuf **controlp, int *flagsp)
2717 {
2718 	struct mbuf *m, *m2;
2719 	int flags, error;
2720 	ssize_t len;
2721 	struct protosw *pr = so->so_proto;
2722 	struct mbuf *nextrecord;
2723 
2724 	if (psa != NULL)
2725 		*psa = NULL;
2726 	if (controlp != NULL)
2727 		*controlp = NULL;
2728 	if (flagsp != NULL)
2729 		flags = *flagsp &~ MSG_EOR;
2730 	else
2731 		flags = 0;
2732 
2733 	/*
2734 	 * For any complicated cases, fall back to the full
2735 	 * soreceive_generic().
2736 	 */
2737 	if (mp0 != NULL || (flags & (MSG_PEEK | MSG_OOB | MSG_TRUNC)))
2738 		return (soreceive_generic(so, psa, uio, mp0, controlp,
2739 		    flagsp));
2740 
2741 	/*
2742 	 * Enforce restrictions on use.
2743 	 */
2744 	KASSERT((pr->pr_flags & PR_WANTRCVD) == 0,
2745 	    ("soreceive_dgram: wantrcvd"));
2746 	KASSERT(pr->pr_flags & PR_ATOMIC, ("soreceive_dgram: !atomic"));
2747 	KASSERT((so->so_rcv.sb_state & SBS_RCVATMARK) == 0,
2748 	    ("soreceive_dgram: SBS_RCVATMARK"));
2749 	KASSERT((so->so_proto->pr_flags & PR_CONNREQUIRED) == 0,
2750 	    ("soreceive_dgram: P_CONNREQUIRED"));
2751 
2752 	/*
2753 	 * Loop blocking while waiting for a datagram.
2754 	 */
2755 	SOCKBUF_LOCK(&so->so_rcv);
2756 	while ((m = so->so_rcv.sb_mb) == NULL) {
2757 		KASSERT(sbavail(&so->so_rcv) == 0,
2758 		    ("soreceive_dgram: sb_mb NULL but sbavail %u",
2759 		    sbavail(&so->so_rcv)));
2760 		if (so->so_error) {
2761 			error = so->so_error;
2762 			so->so_error = 0;
2763 			SOCKBUF_UNLOCK(&so->so_rcv);
2764 			return (error);
2765 		}
2766 		if (so->so_rcv.sb_state & SBS_CANTRCVMORE ||
2767 		    uio->uio_resid == 0) {
2768 			SOCKBUF_UNLOCK(&so->so_rcv);
2769 			return (0);
2770 		}
2771 		if ((so->so_state & SS_NBIO) ||
2772 		    (flags & (MSG_DONTWAIT|MSG_NBIO))) {
2773 			SOCKBUF_UNLOCK(&so->so_rcv);
2774 			return (EWOULDBLOCK);
2775 		}
2776 		SBLASTRECORDCHK(&so->so_rcv);
2777 		SBLASTMBUFCHK(&so->so_rcv);
2778 		error = sbwait(so, SO_RCV);
2779 		if (error) {
2780 			SOCKBUF_UNLOCK(&so->so_rcv);
2781 			return (error);
2782 		}
2783 	}
2784 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2785 
2786 	if (uio->uio_td)
2787 		uio->uio_td->td_ru.ru_msgrcv++;
2788 	SBLASTRECORDCHK(&so->so_rcv);
2789 	SBLASTMBUFCHK(&so->so_rcv);
2790 	nextrecord = m->m_nextpkt;
2791 	if (nextrecord == NULL) {
2792 		KASSERT(so->so_rcv.sb_lastrecord == m,
2793 		    ("soreceive_dgram: lastrecord != m"));
2794 	}
2795 
2796 	KASSERT(so->so_rcv.sb_mb->m_nextpkt == nextrecord,
2797 	    ("soreceive_dgram: m_nextpkt != nextrecord"));
2798 
2799 	/*
2800 	 * Pull 'm' and its chain off the front of the packet queue.
2801 	 */
2802 	so->so_rcv.sb_mb = NULL;
2803 	sockbuf_pushsync(&so->so_rcv, nextrecord);
2804 
2805 	/*
2806 	 * Walk 'm's chain and free that many bytes from the socket buffer.
2807 	 */
2808 	for (m2 = m; m2 != NULL; m2 = m2->m_next)
2809 		sbfree(&so->so_rcv, m2);
2810 
2811 	/*
2812 	 * Do a few last checks before we let go of the lock.
2813 	 */
2814 	SBLASTRECORDCHK(&so->so_rcv);
2815 	SBLASTMBUFCHK(&so->so_rcv);
2816 	SOCKBUF_UNLOCK(&so->so_rcv);
2817 
2818 	if (pr->pr_flags & PR_ADDR) {
2819 		KASSERT(m->m_type == MT_SONAME,
2820 		    ("m->m_type == %d", m->m_type));
2821 		if (psa != NULL)
2822 			*psa = sodupsockaddr(mtod(m, struct sockaddr *),
2823 			    M_NOWAIT);
2824 		m = m_free(m);
2825 	}
2826 	if (m == NULL) {
2827 		/* XXXRW: Can this happen? */
2828 		return (0);
2829 	}
2830 
2831 	/*
2832 	 * Packet to copyout() is now in 'm' and it is disconnected from the
2833 	 * queue.
2834 	 *
2835 	 * Process one or more MT_CONTROL mbufs present before any data mbufs
2836 	 * in the first mbuf chain on the socket buffer.  We call into the
2837 	 * protocol to perform externalization (or freeing if controlp ==
2838 	 * NULL). In some cases there can be only MT_CONTROL mbufs without
2839 	 * MT_DATA mbufs.
2840 	 */
2841 	if (m->m_type == MT_CONTROL) {
2842 		struct mbuf *cm = NULL, *cmn;
2843 		struct mbuf **cme = &cm;
2844 
2845 		do {
2846 			m2 = m->m_next;
2847 			m->m_next = NULL;
2848 			*cme = m;
2849 			cme = &(*cme)->m_next;
2850 			m = m2;
2851 		} while (m != NULL && m->m_type == MT_CONTROL);
2852 		while (cm != NULL) {
2853 			cmn = cm->m_next;
2854 			cm->m_next = NULL;
2855 			if (pr->pr_domain->dom_externalize != NULL) {
2856 				error = (*pr->pr_domain->dom_externalize)
2857 				    (cm, controlp, flags);
2858 			} else if (controlp != NULL)
2859 				*controlp = cm;
2860 			else
2861 				m_freem(cm);
2862 			if (controlp != NULL) {
2863 				while (*controlp != NULL)
2864 					controlp = &(*controlp)->m_next;
2865 			}
2866 			cm = cmn;
2867 		}
2868 	}
2869 	KASSERT(m == NULL || m->m_type == MT_DATA,
2870 	    ("soreceive_dgram: !data"));
2871 	while (m != NULL && uio->uio_resid > 0) {
2872 		len = uio->uio_resid;
2873 		if (len > m->m_len)
2874 			len = m->m_len;
2875 		error = uiomove(mtod(m, char *), (int)len, uio);
2876 		if (error) {
2877 			m_freem(m);
2878 			return (error);
2879 		}
2880 		if (len == m->m_len)
2881 			m = m_free(m);
2882 		else {
2883 			m->m_data += len;
2884 			m->m_len -= len;
2885 		}
2886 	}
2887 	if (m != NULL) {
2888 		flags |= MSG_TRUNC;
2889 		m_freem(m);
2890 	}
2891 	if (flagsp != NULL)
2892 		*flagsp |= flags;
2893 	return (0);
2894 }
2895 
2896 int
2897 soreceive(struct socket *so, struct sockaddr **psa, struct uio *uio,
2898     struct mbuf **mp0, struct mbuf **controlp, int *flagsp)
2899 {
2900 	int error;
2901 
2902 	CURVNET_SET(so->so_vnet);
2903 	error = so->so_proto->pr_soreceive(so, psa, uio, mp0, controlp, flagsp);
2904 	CURVNET_RESTORE();
2905 	return (error);
2906 }
2907 
2908 int
2909 soshutdown(struct socket *so, int how)
2910 {
2911 	struct protosw *pr;
2912 	int error, soerror_enotconn;
2913 
2914 	if (!(how == SHUT_RD || how == SHUT_WR || how == SHUT_RDWR))
2915 		return (EINVAL);
2916 
2917 	soerror_enotconn = 0;
2918 	SOCK_LOCK(so);
2919 	if ((so->so_state &
2920 	    (SS_ISCONNECTED | SS_ISCONNECTING | SS_ISDISCONNECTING)) == 0) {
2921 		/*
2922 		 * POSIX mandates us to return ENOTCONN when shutdown(2) is
2923 		 * invoked on a datagram sockets, however historically we would
2924 		 * actually tear socket down. This is known to be leveraged by
2925 		 * some applications to unblock process waiting in recvXXX(2)
2926 		 * by other process that it shares that socket with. Try to meet
2927 		 * both backward-compatibility and POSIX requirements by forcing
2928 		 * ENOTCONN but still asking protocol to perform pru_shutdown().
2929 		 */
2930 		if (so->so_type != SOCK_DGRAM && !SOLISTENING(so)) {
2931 			SOCK_UNLOCK(so);
2932 			return (ENOTCONN);
2933 		}
2934 		soerror_enotconn = 1;
2935 	}
2936 
2937 	if (SOLISTENING(so)) {
2938 		if (how != SHUT_WR) {
2939 			so->so_error = ECONNABORTED;
2940 			solisten_wakeup(so);	/* unlocks so */
2941 		} else {
2942 			SOCK_UNLOCK(so);
2943 		}
2944 		goto done;
2945 	}
2946 	SOCK_UNLOCK(so);
2947 
2948 	CURVNET_SET(so->so_vnet);
2949 	pr = so->so_proto;
2950 	if (pr->pr_flush != NULL)
2951 		pr->pr_flush(so, how);
2952 	if (how != SHUT_WR)
2953 		sorflush(so);
2954 	if (how != SHUT_RD) {
2955 		error = pr->pr_shutdown(so);
2956 		wakeup(&so->so_timeo);
2957 		CURVNET_RESTORE();
2958 		return ((error == 0 && soerror_enotconn) ? ENOTCONN : error);
2959 	}
2960 	wakeup(&so->so_timeo);
2961 	CURVNET_RESTORE();
2962 
2963 done:
2964 	return (soerror_enotconn ? ENOTCONN : 0);
2965 }
2966 
2967 void
2968 sorflush(struct socket *so)
2969 {
2970 	struct protosw *pr;
2971 	int error;
2972 
2973 	VNET_SO_ASSERT(so);
2974 
2975 	/*
2976 	 * Dislodge threads currently blocked in receive and wait to acquire
2977 	 * a lock against other simultaneous readers before clearing the
2978 	 * socket buffer.  Don't let our acquire be interrupted by a signal
2979 	 * despite any existing socket disposition on interruptable waiting.
2980 	 */
2981 	socantrcvmore(so);
2982 
2983 	error = SOCK_IO_RECV_LOCK(so, SBL_WAIT | SBL_NOINTR);
2984 	if (error != 0) {
2985 		KASSERT(SOLISTENING(so),
2986 		    ("%s: soiolock(%p) failed", __func__, so));
2987 		return;
2988 	}
2989 
2990 	pr = so->so_proto;
2991 	if (pr->pr_flags & PR_RIGHTS) {
2992 		MPASS(pr->pr_domain->dom_dispose != NULL);
2993 		(*pr->pr_domain->dom_dispose)(so);
2994 	} else {
2995 		sbrelease(so, SO_RCV);
2996 		SOCK_IO_RECV_UNLOCK(so);
2997 	}
2998 
2999 }
3000 
3001 /*
3002  * Wrapper for Socket established helper hook.
3003  * Parameters: socket, context of the hook point, hook id.
3004  */
3005 static int inline
3006 hhook_run_socket(struct socket *so, void *hctx, int32_t h_id)
3007 {
3008 	struct socket_hhook_data hhook_data = {
3009 		.so = so,
3010 		.hctx = hctx,
3011 		.m = NULL,
3012 		.status = 0
3013 	};
3014 
3015 	CURVNET_SET(so->so_vnet);
3016 	HHOOKS_RUN_IF(V_socket_hhh[h_id], &hhook_data, &so->osd);
3017 	CURVNET_RESTORE();
3018 
3019 	/* Ugly but needed, since hhooks return void for now */
3020 	return (hhook_data.status);
3021 }
3022 
3023 /*
3024  * Perhaps this routine, and sooptcopyout(), below, ought to come in an
3025  * additional variant to handle the case where the option value needs to be
3026  * some kind of integer, but not a specific size.  In addition to their use
3027  * here, these functions are also called by the protocol-level pr_ctloutput()
3028  * routines.
3029  */
3030 int
3031 sooptcopyin(struct sockopt *sopt, void *buf, size_t len, size_t minlen)
3032 {
3033 	size_t	valsize;
3034 
3035 	/*
3036 	 * If the user gives us more than we wanted, we ignore it, but if we
3037 	 * don't get the minimum length the caller wants, we return EINVAL.
3038 	 * On success, sopt->sopt_valsize is set to however much we actually
3039 	 * retrieved.
3040 	 */
3041 	if ((valsize = sopt->sopt_valsize) < minlen)
3042 		return EINVAL;
3043 	if (valsize > len)
3044 		sopt->sopt_valsize = valsize = len;
3045 
3046 	if (sopt->sopt_td != NULL)
3047 		return (copyin(sopt->sopt_val, buf, valsize));
3048 
3049 	bcopy(sopt->sopt_val, buf, valsize);
3050 	return (0);
3051 }
3052 
3053 /*
3054  * Kernel version of setsockopt(2).
3055  *
3056  * XXX: optlen is size_t, not socklen_t
3057  */
3058 int
3059 so_setsockopt(struct socket *so, int level, int optname, void *optval,
3060     size_t optlen)
3061 {
3062 	struct sockopt sopt;
3063 
3064 	sopt.sopt_level = level;
3065 	sopt.sopt_name = optname;
3066 	sopt.sopt_dir = SOPT_SET;
3067 	sopt.sopt_val = optval;
3068 	sopt.sopt_valsize = optlen;
3069 	sopt.sopt_td = NULL;
3070 	return (sosetopt(so, &sopt));
3071 }
3072 
3073 int
3074 sosetopt(struct socket *so, struct sockopt *sopt)
3075 {
3076 	int	error, optval;
3077 	struct	linger l;
3078 	struct	timeval tv;
3079 	sbintime_t val, *valp;
3080 	uint32_t val32;
3081 #ifdef MAC
3082 	struct mac extmac;
3083 #endif
3084 
3085 	CURVNET_SET(so->so_vnet);
3086 	error = 0;
3087 	if (sopt->sopt_level != SOL_SOCKET) {
3088 		if (so->so_proto->pr_ctloutput != NULL)
3089 			error = (*so->so_proto->pr_ctloutput)(so, sopt);
3090 		else
3091 			error = ENOPROTOOPT;
3092 	} else {
3093 		switch (sopt->sopt_name) {
3094 		case SO_ACCEPTFILTER:
3095 			error = accept_filt_setopt(so, sopt);
3096 			if (error)
3097 				goto bad;
3098 			break;
3099 
3100 		case SO_LINGER:
3101 			error = sooptcopyin(sopt, &l, sizeof l, sizeof l);
3102 			if (error)
3103 				goto bad;
3104 			if (l.l_linger < 0 ||
3105 			    l.l_linger > USHRT_MAX ||
3106 			    l.l_linger > (INT_MAX / hz)) {
3107 				error = EDOM;
3108 				goto bad;
3109 			}
3110 			SOCK_LOCK(so);
3111 			so->so_linger = l.l_linger;
3112 			if (l.l_onoff)
3113 				so->so_options |= SO_LINGER;
3114 			else
3115 				so->so_options &= ~SO_LINGER;
3116 			SOCK_UNLOCK(so);
3117 			break;
3118 
3119 		case SO_DEBUG:
3120 		case SO_KEEPALIVE:
3121 		case SO_DONTROUTE:
3122 		case SO_USELOOPBACK:
3123 		case SO_BROADCAST:
3124 		case SO_REUSEADDR:
3125 		case SO_REUSEPORT:
3126 		case SO_REUSEPORT_LB:
3127 		case SO_OOBINLINE:
3128 		case SO_TIMESTAMP:
3129 		case SO_BINTIME:
3130 		case SO_NOSIGPIPE:
3131 		case SO_NO_DDP:
3132 		case SO_NO_OFFLOAD:
3133 		case SO_RERROR:
3134 			error = sooptcopyin(sopt, &optval, sizeof optval,
3135 			    sizeof optval);
3136 			if (error)
3137 				goto bad;
3138 			SOCK_LOCK(so);
3139 			if (optval)
3140 				so->so_options |= sopt->sopt_name;
3141 			else
3142 				so->so_options &= ~sopt->sopt_name;
3143 			SOCK_UNLOCK(so);
3144 			break;
3145 
3146 		case SO_SETFIB:
3147 			error = sooptcopyin(sopt, &optval, sizeof optval,
3148 			    sizeof optval);
3149 			if (error)
3150 				goto bad;
3151 
3152 			if (optval < 0 || optval >= rt_numfibs) {
3153 				error = EINVAL;
3154 				goto bad;
3155 			}
3156 			if (((so->so_proto->pr_domain->dom_family == PF_INET) ||
3157 			   (so->so_proto->pr_domain->dom_family == PF_INET6) ||
3158 			   (so->so_proto->pr_domain->dom_family == PF_ROUTE)))
3159 				so->so_fibnum = optval;
3160 			else
3161 				so->so_fibnum = 0;
3162 			break;
3163 
3164 		case SO_USER_COOKIE:
3165 			error = sooptcopyin(sopt, &val32, sizeof val32,
3166 			    sizeof val32);
3167 			if (error)
3168 				goto bad;
3169 			so->so_user_cookie = val32;
3170 			break;
3171 
3172 		case SO_SNDBUF:
3173 		case SO_RCVBUF:
3174 		case SO_SNDLOWAT:
3175 		case SO_RCVLOWAT:
3176 			error = so->so_proto->pr_setsbopt(so, sopt);
3177 			if (error)
3178 				goto bad;
3179 			break;
3180 
3181 		case SO_SNDTIMEO:
3182 		case SO_RCVTIMEO:
3183 #ifdef COMPAT_FREEBSD32
3184 			if (SV_CURPROC_FLAG(SV_ILP32)) {
3185 				struct timeval32 tv32;
3186 
3187 				error = sooptcopyin(sopt, &tv32, sizeof tv32,
3188 				    sizeof tv32);
3189 				CP(tv32, tv, tv_sec);
3190 				CP(tv32, tv, tv_usec);
3191 			} else
3192 #endif
3193 				error = sooptcopyin(sopt, &tv, sizeof tv,
3194 				    sizeof tv);
3195 			if (error)
3196 				goto bad;
3197 			if (tv.tv_sec < 0 || tv.tv_usec < 0 ||
3198 			    tv.tv_usec >= 1000000) {
3199 				error = EDOM;
3200 				goto bad;
3201 			}
3202 			if (tv.tv_sec > INT32_MAX)
3203 				val = SBT_MAX;
3204 			else
3205 				val = tvtosbt(tv);
3206 			SOCK_LOCK(so);
3207 			valp = sopt->sopt_name == SO_SNDTIMEO ?
3208 			    (SOLISTENING(so) ? &so->sol_sbsnd_timeo :
3209 			    &so->so_snd.sb_timeo) :
3210 			    (SOLISTENING(so) ? &so->sol_sbrcv_timeo :
3211 			    &so->so_rcv.sb_timeo);
3212 			*valp = val;
3213 			SOCK_UNLOCK(so);
3214 			break;
3215 
3216 		case SO_LABEL:
3217 #ifdef MAC
3218 			error = sooptcopyin(sopt, &extmac, sizeof extmac,
3219 			    sizeof extmac);
3220 			if (error)
3221 				goto bad;
3222 			error = mac_setsockopt_label(sopt->sopt_td->td_ucred,
3223 			    so, &extmac);
3224 #else
3225 			error = EOPNOTSUPP;
3226 #endif
3227 			break;
3228 
3229 		case SO_TS_CLOCK:
3230 			error = sooptcopyin(sopt, &optval, sizeof optval,
3231 			    sizeof optval);
3232 			if (error)
3233 				goto bad;
3234 			if (optval < 0 || optval > SO_TS_CLOCK_MAX) {
3235 				error = EINVAL;
3236 				goto bad;
3237 			}
3238 			so->so_ts_clock = optval;
3239 			break;
3240 
3241 		case SO_MAX_PACING_RATE:
3242 			error = sooptcopyin(sopt, &val32, sizeof(val32),
3243 			    sizeof(val32));
3244 			if (error)
3245 				goto bad;
3246 			so->so_max_pacing_rate = val32;
3247 			break;
3248 
3249 		default:
3250 			if (V_socket_hhh[HHOOK_SOCKET_OPT]->hhh_nhooks > 0)
3251 				error = hhook_run_socket(so, sopt,
3252 				    HHOOK_SOCKET_OPT);
3253 			else
3254 				error = ENOPROTOOPT;
3255 			break;
3256 		}
3257 		if (error == 0 && so->so_proto->pr_ctloutput != NULL)
3258 			(void)(*so->so_proto->pr_ctloutput)(so, sopt);
3259 	}
3260 bad:
3261 	CURVNET_RESTORE();
3262 	return (error);
3263 }
3264 
3265 /*
3266  * Helper routine for getsockopt.
3267  */
3268 int
3269 sooptcopyout(struct sockopt *sopt, const void *buf, size_t len)
3270 {
3271 	int	error;
3272 	size_t	valsize;
3273 
3274 	error = 0;
3275 
3276 	/*
3277 	 * Documented get behavior is that we always return a value, possibly
3278 	 * truncated to fit in the user's buffer.  Traditional behavior is
3279 	 * that we always tell the user precisely how much we copied, rather
3280 	 * than something useful like the total amount we had available for
3281 	 * her.  Note that this interface is not idempotent; the entire
3282 	 * answer must be generated ahead of time.
3283 	 */
3284 	valsize = min(len, sopt->sopt_valsize);
3285 	sopt->sopt_valsize = valsize;
3286 	if (sopt->sopt_val != NULL) {
3287 		if (sopt->sopt_td != NULL)
3288 			error = copyout(buf, sopt->sopt_val, valsize);
3289 		else
3290 			bcopy(buf, sopt->sopt_val, valsize);
3291 	}
3292 	return (error);
3293 }
3294 
3295 int
3296 sogetopt(struct socket *so, struct sockopt *sopt)
3297 {
3298 	int	error, optval;
3299 	struct	linger l;
3300 	struct	timeval tv;
3301 #ifdef MAC
3302 	struct mac extmac;
3303 #endif
3304 
3305 	CURVNET_SET(so->so_vnet);
3306 	error = 0;
3307 	if (sopt->sopt_level != SOL_SOCKET) {
3308 		if (so->so_proto->pr_ctloutput != NULL)
3309 			error = (*so->so_proto->pr_ctloutput)(so, sopt);
3310 		else
3311 			error = ENOPROTOOPT;
3312 		CURVNET_RESTORE();
3313 		return (error);
3314 	} else {
3315 		switch (sopt->sopt_name) {
3316 		case SO_ACCEPTFILTER:
3317 			error = accept_filt_getopt(so, sopt);
3318 			break;
3319 
3320 		case SO_LINGER:
3321 			SOCK_LOCK(so);
3322 			l.l_onoff = so->so_options & SO_LINGER;
3323 			l.l_linger = so->so_linger;
3324 			SOCK_UNLOCK(so);
3325 			error = sooptcopyout(sopt, &l, sizeof l);
3326 			break;
3327 
3328 		case SO_USELOOPBACK:
3329 		case SO_DONTROUTE:
3330 		case SO_DEBUG:
3331 		case SO_KEEPALIVE:
3332 		case SO_REUSEADDR:
3333 		case SO_REUSEPORT:
3334 		case SO_REUSEPORT_LB:
3335 		case SO_BROADCAST:
3336 		case SO_OOBINLINE:
3337 		case SO_ACCEPTCONN:
3338 		case SO_TIMESTAMP:
3339 		case SO_BINTIME:
3340 		case SO_NOSIGPIPE:
3341 		case SO_NO_DDP:
3342 		case SO_NO_OFFLOAD:
3343 		case SO_RERROR:
3344 			optval = so->so_options & sopt->sopt_name;
3345 integer:
3346 			error = sooptcopyout(sopt, &optval, sizeof optval);
3347 			break;
3348 
3349 		case SO_DOMAIN:
3350 			optval = so->so_proto->pr_domain->dom_family;
3351 			goto integer;
3352 
3353 		case SO_TYPE:
3354 			optval = so->so_type;
3355 			goto integer;
3356 
3357 		case SO_PROTOCOL:
3358 			optval = so->so_proto->pr_protocol;
3359 			goto integer;
3360 
3361 		case SO_ERROR:
3362 			SOCK_LOCK(so);
3363 			if (so->so_error) {
3364 				optval = so->so_error;
3365 				so->so_error = 0;
3366 			} else {
3367 				optval = so->so_rerror;
3368 				so->so_rerror = 0;
3369 			}
3370 			SOCK_UNLOCK(so);
3371 			goto integer;
3372 
3373 		case SO_SNDBUF:
3374 			optval = SOLISTENING(so) ? so->sol_sbsnd_hiwat :
3375 			    so->so_snd.sb_hiwat;
3376 			goto integer;
3377 
3378 		case SO_RCVBUF:
3379 			optval = SOLISTENING(so) ? so->sol_sbrcv_hiwat :
3380 			    so->so_rcv.sb_hiwat;
3381 			goto integer;
3382 
3383 		case SO_SNDLOWAT:
3384 			optval = SOLISTENING(so) ? so->sol_sbsnd_lowat :
3385 			    so->so_snd.sb_lowat;
3386 			goto integer;
3387 
3388 		case SO_RCVLOWAT:
3389 			optval = SOLISTENING(so) ? so->sol_sbrcv_lowat :
3390 			    so->so_rcv.sb_lowat;
3391 			goto integer;
3392 
3393 		case SO_SNDTIMEO:
3394 		case SO_RCVTIMEO:
3395 			SOCK_LOCK(so);
3396 			tv = sbttotv(sopt->sopt_name == SO_SNDTIMEO ?
3397 			    (SOLISTENING(so) ? so->sol_sbsnd_timeo :
3398 			    so->so_snd.sb_timeo) :
3399 			    (SOLISTENING(so) ? so->sol_sbrcv_timeo :
3400 			    so->so_rcv.sb_timeo));
3401 			SOCK_UNLOCK(so);
3402 #ifdef COMPAT_FREEBSD32
3403 			if (SV_CURPROC_FLAG(SV_ILP32)) {
3404 				struct timeval32 tv32;
3405 
3406 				CP(tv, tv32, tv_sec);
3407 				CP(tv, tv32, tv_usec);
3408 				error = sooptcopyout(sopt, &tv32, sizeof tv32);
3409 			} else
3410 #endif
3411 				error = sooptcopyout(sopt, &tv, sizeof tv);
3412 			break;
3413 
3414 		case SO_LABEL:
3415 #ifdef MAC
3416 			error = sooptcopyin(sopt, &extmac, sizeof(extmac),
3417 			    sizeof(extmac));
3418 			if (error)
3419 				goto bad;
3420 			error = mac_getsockopt_label(sopt->sopt_td->td_ucred,
3421 			    so, &extmac);
3422 			if (error)
3423 				goto bad;
3424 			error = sooptcopyout(sopt, &extmac, sizeof extmac);
3425 #else
3426 			error = EOPNOTSUPP;
3427 #endif
3428 			break;
3429 
3430 		case SO_PEERLABEL:
3431 #ifdef MAC
3432 			error = sooptcopyin(sopt, &extmac, sizeof(extmac),
3433 			    sizeof(extmac));
3434 			if (error)
3435 				goto bad;
3436 			error = mac_getsockopt_peerlabel(
3437 			    sopt->sopt_td->td_ucred, so, &extmac);
3438 			if (error)
3439 				goto bad;
3440 			error = sooptcopyout(sopt, &extmac, sizeof extmac);
3441 #else
3442 			error = EOPNOTSUPP;
3443 #endif
3444 			break;
3445 
3446 		case SO_LISTENQLIMIT:
3447 			optval = SOLISTENING(so) ? so->sol_qlimit : 0;
3448 			goto integer;
3449 
3450 		case SO_LISTENQLEN:
3451 			optval = SOLISTENING(so) ? so->sol_qlen : 0;
3452 			goto integer;
3453 
3454 		case SO_LISTENINCQLEN:
3455 			optval = SOLISTENING(so) ? so->sol_incqlen : 0;
3456 			goto integer;
3457 
3458 		case SO_TS_CLOCK:
3459 			optval = so->so_ts_clock;
3460 			goto integer;
3461 
3462 		case SO_MAX_PACING_RATE:
3463 			optval = so->so_max_pacing_rate;
3464 			goto integer;
3465 
3466 		default:
3467 			if (V_socket_hhh[HHOOK_SOCKET_OPT]->hhh_nhooks > 0)
3468 				error = hhook_run_socket(so, sopt,
3469 				    HHOOK_SOCKET_OPT);
3470 			else
3471 				error = ENOPROTOOPT;
3472 			break;
3473 		}
3474 	}
3475 #ifdef MAC
3476 bad:
3477 #endif
3478 	CURVNET_RESTORE();
3479 	return (error);
3480 }
3481 
3482 int
3483 soopt_getm(struct sockopt *sopt, struct mbuf **mp)
3484 {
3485 	struct mbuf *m, *m_prev;
3486 	int sopt_size = sopt->sopt_valsize;
3487 
3488 	MGET(m, sopt->sopt_td ? M_WAITOK : M_NOWAIT, MT_DATA);
3489 	if (m == NULL)
3490 		return ENOBUFS;
3491 	if (sopt_size > MLEN) {
3492 		MCLGET(m, sopt->sopt_td ? M_WAITOK : M_NOWAIT);
3493 		if ((m->m_flags & M_EXT) == 0) {
3494 			m_free(m);
3495 			return ENOBUFS;
3496 		}
3497 		m->m_len = min(MCLBYTES, sopt_size);
3498 	} else {
3499 		m->m_len = min(MLEN, sopt_size);
3500 	}
3501 	sopt_size -= m->m_len;
3502 	*mp = m;
3503 	m_prev = m;
3504 
3505 	while (sopt_size) {
3506 		MGET(m, sopt->sopt_td ? M_WAITOK : M_NOWAIT, MT_DATA);
3507 		if (m == NULL) {
3508 			m_freem(*mp);
3509 			return ENOBUFS;
3510 		}
3511 		if (sopt_size > MLEN) {
3512 			MCLGET(m, sopt->sopt_td != NULL ? M_WAITOK :
3513 			    M_NOWAIT);
3514 			if ((m->m_flags & M_EXT) == 0) {
3515 				m_freem(m);
3516 				m_freem(*mp);
3517 				return ENOBUFS;
3518 			}
3519 			m->m_len = min(MCLBYTES, sopt_size);
3520 		} else {
3521 			m->m_len = min(MLEN, sopt_size);
3522 		}
3523 		sopt_size -= m->m_len;
3524 		m_prev->m_next = m;
3525 		m_prev = m;
3526 	}
3527 	return (0);
3528 }
3529 
3530 int
3531 soopt_mcopyin(struct sockopt *sopt, struct mbuf *m)
3532 {
3533 	struct mbuf *m0 = m;
3534 
3535 	if (sopt->sopt_val == NULL)
3536 		return (0);
3537 	while (m != NULL && sopt->sopt_valsize >= m->m_len) {
3538 		if (sopt->sopt_td != NULL) {
3539 			int error;
3540 
3541 			error = copyin(sopt->sopt_val, mtod(m, char *),
3542 			    m->m_len);
3543 			if (error != 0) {
3544 				m_freem(m0);
3545 				return(error);
3546 			}
3547 		} else
3548 			bcopy(sopt->sopt_val, mtod(m, char *), m->m_len);
3549 		sopt->sopt_valsize -= m->m_len;
3550 		sopt->sopt_val = (char *)sopt->sopt_val + m->m_len;
3551 		m = m->m_next;
3552 	}
3553 	if (m != NULL) /* should be allocated enoughly at ip6_sooptmcopyin() */
3554 		panic("ip6_sooptmcopyin");
3555 	return (0);
3556 }
3557 
3558 int
3559 soopt_mcopyout(struct sockopt *sopt, struct mbuf *m)
3560 {
3561 	struct mbuf *m0 = m;
3562 	size_t valsize = 0;
3563 
3564 	if (sopt->sopt_val == NULL)
3565 		return (0);
3566 	while (m != NULL && sopt->sopt_valsize >= m->m_len) {
3567 		if (sopt->sopt_td != NULL) {
3568 			int error;
3569 
3570 			error = copyout(mtod(m, char *), sopt->sopt_val,
3571 			    m->m_len);
3572 			if (error != 0) {
3573 				m_freem(m0);
3574 				return(error);
3575 			}
3576 		} else
3577 			bcopy(mtod(m, char *), sopt->sopt_val, m->m_len);
3578 		sopt->sopt_valsize -= m->m_len;
3579 		sopt->sopt_val = (char *)sopt->sopt_val + m->m_len;
3580 		valsize += m->m_len;
3581 		m = m->m_next;
3582 	}
3583 	if (m != NULL) {
3584 		/* enough soopt buffer should be given from user-land */
3585 		m_freem(m0);
3586 		return(EINVAL);
3587 	}
3588 	sopt->sopt_valsize = valsize;
3589 	return (0);
3590 }
3591 
3592 /*
3593  * sohasoutofband(): protocol notifies socket layer of the arrival of new
3594  * out-of-band data, which will then notify socket consumers.
3595  */
3596 void
3597 sohasoutofband(struct socket *so)
3598 {
3599 
3600 	if (so->so_sigio != NULL)
3601 		pgsigio(&so->so_sigio, SIGURG, 0);
3602 	selwakeuppri(&so->so_rdsel, PSOCK);
3603 }
3604 
3605 int
3606 sopoll(struct socket *so, int events, struct ucred *active_cred,
3607     struct thread *td)
3608 {
3609 
3610 	/*
3611 	 * We do not need to set or assert curvnet as long as everyone uses
3612 	 * sopoll_generic().
3613 	 */
3614 	return (so->so_proto->pr_sopoll(so, events, active_cred, td));
3615 }
3616 
3617 int
3618 sopoll_generic(struct socket *so, int events, struct ucred *active_cred,
3619     struct thread *td)
3620 {
3621 	int revents;
3622 
3623 	SOCK_LOCK(so);
3624 	if (SOLISTENING(so)) {
3625 		if (!(events & (POLLIN | POLLRDNORM)))
3626 			revents = 0;
3627 		else if (!TAILQ_EMPTY(&so->sol_comp))
3628 			revents = events & (POLLIN | POLLRDNORM);
3629 		else if ((events & POLLINIGNEOF) == 0 && so->so_error)
3630 			revents = (events & (POLLIN | POLLRDNORM)) | POLLHUP;
3631 		else {
3632 			selrecord(td, &so->so_rdsel);
3633 			revents = 0;
3634 		}
3635 	} else {
3636 		revents = 0;
3637 		SOCK_SENDBUF_LOCK(so);
3638 		SOCK_RECVBUF_LOCK(so);
3639 		if (events & (POLLIN | POLLRDNORM))
3640 			if (soreadabledata(so))
3641 				revents |= events & (POLLIN | POLLRDNORM);
3642 		if (events & (POLLOUT | POLLWRNORM))
3643 			if (sowriteable(so))
3644 				revents |= events & (POLLOUT | POLLWRNORM);
3645 		if (events & (POLLPRI | POLLRDBAND))
3646 			if (so->so_oobmark ||
3647 			    (so->so_rcv.sb_state & SBS_RCVATMARK))
3648 				revents |= events & (POLLPRI | POLLRDBAND);
3649 		if ((events & POLLINIGNEOF) == 0) {
3650 			if (so->so_rcv.sb_state & SBS_CANTRCVMORE) {
3651 				revents |= events & (POLLIN | POLLRDNORM);
3652 				if (so->so_snd.sb_state & SBS_CANTSENDMORE)
3653 					revents |= POLLHUP;
3654 			}
3655 		}
3656 		if (so->so_rcv.sb_state & SBS_CANTRCVMORE)
3657 			revents |= events & POLLRDHUP;
3658 		if (revents == 0) {
3659 			if (events &
3660 			    (POLLIN | POLLPRI | POLLRDNORM | POLLRDBAND | POLLRDHUP)) {
3661 				selrecord(td, &so->so_rdsel);
3662 				so->so_rcv.sb_flags |= SB_SEL;
3663 			}
3664 			if (events & (POLLOUT | POLLWRNORM)) {
3665 				selrecord(td, &so->so_wrsel);
3666 				so->so_snd.sb_flags |= SB_SEL;
3667 			}
3668 		}
3669 		SOCK_RECVBUF_UNLOCK(so);
3670 		SOCK_SENDBUF_UNLOCK(so);
3671 	}
3672 	SOCK_UNLOCK(so);
3673 	return (revents);
3674 }
3675 
3676 int
3677 soo_kqfilter(struct file *fp, struct knote *kn)
3678 {
3679 	struct socket *so = kn->kn_fp->f_data;
3680 	struct sockbuf *sb;
3681 	sb_which which;
3682 	struct knlist *knl;
3683 
3684 	switch (kn->kn_filter) {
3685 	case EVFILT_READ:
3686 		kn->kn_fop = &soread_filtops;
3687 		knl = &so->so_rdsel.si_note;
3688 		sb = &so->so_rcv;
3689 		which = SO_RCV;
3690 		break;
3691 	case EVFILT_WRITE:
3692 		kn->kn_fop = &sowrite_filtops;
3693 		knl = &so->so_wrsel.si_note;
3694 		sb = &so->so_snd;
3695 		which = SO_SND;
3696 		break;
3697 	case EVFILT_EMPTY:
3698 		kn->kn_fop = &soempty_filtops;
3699 		knl = &so->so_wrsel.si_note;
3700 		sb = &so->so_snd;
3701 		which = SO_SND;
3702 		break;
3703 	default:
3704 		return (EINVAL);
3705 	}
3706 
3707 	SOCK_LOCK(so);
3708 	if (SOLISTENING(so)) {
3709 		knlist_add(knl, kn, 1);
3710 	} else {
3711 		SOCK_BUF_LOCK(so, which);
3712 		knlist_add(knl, kn, 1);
3713 		sb->sb_flags |= SB_KNOTE;
3714 		SOCK_BUF_UNLOCK(so, which);
3715 	}
3716 	SOCK_UNLOCK(so);
3717 	return (0);
3718 }
3719 
3720 static void
3721 filt_sordetach(struct knote *kn)
3722 {
3723 	struct socket *so = kn->kn_fp->f_data;
3724 
3725 	so_rdknl_lock(so);
3726 	knlist_remove(&so->so_rdsel.si_note, kn, 1);
3727 	if (!SOLISTENING(so) && knlist_empty(&so->so_rdsel.si_note))
3728 		so->so_rcv.sb_flags &= ~SB_KNOTE;
3729 	so_rdknl_unlock(so);
3730 }
3731 
3732 /*ARGSUSED*/
3733 static int
3734 filt_soread(struct knote *kn, long hint)
3735 {
3736 	struct socket *so;
3737 
3738 	so = kn->kn_fp->f_data;
3739 
3740 	if (SOLISTENING(so)) {
3741 		SOCK_LOCK_ASSERT(so);
3742 		kn->kn_data = so->sol_qlen;
3743 		if (so->so_error) {
3744 			kn->kn_flags |= EV_EOF;
3745 			kn->kn_fflags = so->so_error;
3746 			return (1);
3747 		}
3748 		return (!TAILQ_EMPTY(&so->sol_comp));
3749 	}
3750 
3751 	SOCK_RECVBUF_LOCK_ASSERT(so);
3752 
3753 	kn->kn_data = sbavail(&so->so_rcv) - so->so_rcv.sb_ctl;
3754 	if (so->so_rcv.sb_state & SBS_CANTRCVMORE) {
3755 		kn->kn_flags |= EV_EOF;
3756 		kn->kn_fflags = so->so_error;
3757 		return (1);
3758 	} else if (so->so_error || so->so_rerror)
3759 		return (1);
3760 
3761 	if (kn->kn_sfflags & NOTE_LOWAT) {
3762 		if (kn->kn_data >= kn->kn_sdata)
3763 			return (1);
3764 	} else if (sbavail(&so->so_rcv) >= so->so_rcv.sb_lowat)
3765 		return (1);
3766 
3767 	/* This hook returning non-zero indicates an event, not error */
3768 	return (hhook_run_socket(so, NULL, HHOOK_FILT_SOREAD));
3769 }
3770 
3771 static void
3772 filt_sowdetach(struct knote *kn)
3773 {
3774 	struct socket *so = kn->kn_fp->f_data;
3775 
3776 	so_wrknl_lock(so);
3777 	knlist_remove(&so->so_wrsel.si_note, kn, 1);
3778 	if (!SOLISTENING(so) && knlist_empty(&so->so_wrsel.si_note))
3779 		so->so_snd.sb_flags &= ~SB_KNOTE;
3780 	so_wrknl_unlock(so);
3781 }
3782 
3783 /*ARGSUSED*/
3784 static int
3785 filt_sowrite(struct knote *kn, long hint)
3786 {
3787 	struct socket *so;
3788 
3789 	so = kn->kn_fp->f_data;
3790 
3791 	if (SOLISTENING(so))
3792 		return (0);
3793 
3794 	SOCK_SENDBUF_LOCK_ASSERT(so);
3795 	kn->kn_data = sbspace(&so->so_snd);
3796 
3797 	hhook_run_socket(so, kn, HHOOK_FILT_SOWRITE);
3798 
3799 	if (so->so_snd.sb_state & SBS_CANTSENDMORE) {
3800 		kn->kn_flags |= EV_EOF;
3801 		kn->kn_fflags = so->so_error;
3802 		return (1);
3803 	} else if (so->so_error)	/* temporary udp error */
3804 		return (1);
3805 	else if (((so->so_state & SS_ISCONNECTED) == 0) &&
3806 	    (so->so_proto->pr_flags & PR_CONNREQUIRED))
3807 		return (0);
3808 	else if (kn->kn_sfflags & NOTE_LOWAT)
3809 		return (kn->kn_data >= kn->kn_sdata);
3810 	else
3811 		return (kn->kn_data >= so->so_snd.sb_lowat);
3812 }
3813 
3814 static int
3815 filt_soempty(struct knote *kn, long hint)
3816 {
3817 	struct socket *so;
3818 
3819 	so = kn->kn_fp->f_data;
3820 
3821 	if (SOLISTENING(so))
3822 		return (1);
3823 
3824 	SOCK_SENDBUF_LOCK_ASSERT(so);
3825 	kn->kn_data = sbused(&so->so_snd);
3826 
3827 	if (kn->kn_data == 0)
3828 		return (1);
3829 	else
3830 		return (0);
3831 }
3832 
3833 int
3834 socheckuid(struct socket *so, uid_t uid)
3835 {
3836 
3837 	if (so == NULL)
3838 		return (EPERM);
3839 	if (so->so_cred->cr_uid != uid)
3840 		return (EPERM);
3841 	return (0);
3842 }
3843 
3844 /*
3845  * These functions are used by protocols to notify the socket layer (and its
3846  * consumers) of state changes in the sockets driven by protocol-side events.
3847  */
3848 
3849 /*
3850  * Procedures to manipulate state flags of socket and do appropriate wakeups.
3851  *
3852  * Normal sequence from the active (originating) side is that
3853  * soisconnecting() is called during processing of connect() call, resulting
3854  * in an eventual call to soisconnected() if/when the connection is
3855  * established.  When the connection is torn down soisdisconnecting() is
3856  * called during processing of disconnect() call, and soisdisconnected() is
3857  * called when the connection to the peer is totally severed.  The semantics
3858  * of these routines are such that connectionless protocols can call
3859  * soisconnected() and soisdisconnected() only, bypassing the in-progress
3860  * calls when setting up a ``connection'' takes no time.
3861  *
3862  * From the passive side, a socket is created with two queues of sockets:
3863  * so_incomp for connections in progress and so_comp for connections already
3864  * made and awaiting user acceptance.  As a protocol is preparing incoming
3865  * connections, it creates a socket structure queued on so_incomp by calling
3866  * sonewconn().  When the connection is established, soisconnected() is
3867  * called, and transfers the socket structure to so_comp, making it available
3868  * to accept().
3869  *
3870  * If a socket is closed with sockets on either so_incomp or so_comp, these
3871  * sockets are dropped.
3872  *
3873  * If higher-level protocols are implemented in the kernel, the wakeups done
3874  * here will sometimes cause software-interrupt process scheduling.
3875  */
3876 void
3877 soisconnecting(struct socket *so)
3878 {
3879 
3880 	SOCK_LOCK(so);
3881 	so->so_state &= ~(SS_ISCONNECTED|SS_ISDISCONNECTING);
3882 	so->so_state |= SS_ISCONNECTING;
3883 	SOCK_UNLOCK(so);
3884 }
3885 
3886 void
3887 soisconnected(struct socket *so)
3888 {
3889 	bool last __diagused;
3890 
3891 	SOCK_LOCK(so);
3892 	so->so_state &= ~(SS_ISCONNECTING|SS_ISDISCONNECTING|SS_ISCONFIRMING);
3893 	so->so_state |= SS_ISCONNECTED;
3894 
3895 	if (so->so_qstate == SQ_INCOMP) {
3896 		struct socket *head = so->so_listen;
3897 		int ret;
3898 
3899 		KASSERT(head, ("%s: so %p on incomp of NULL", __func__, so));
3900 		/*
3901 		 * Promoting a socket from incomplete queue to complete, we
3902 		 * need to go through reverse order of locking.  We first do
3903 		 * trylock, and if that doesn't succeed, we go the hard way
3904 		 * leaving a reference and rechecking consistency after proper
3905 		 * locking.
3906 		 */
3907 		if (__predict_false(SOLISTEN_TRYLOCK(head) == 0)) {
3908 			soref(head);
3909 			SOCK_UNLOCK(so);
3910 			SOLISTEN_LOCK(head);
3911 			SOCK_LOCK(so);
3912 			if (__predict_false(head != so->so_listen)) {
3913 				/*
3914 				 * The socket went off the listen queue,
3915 				 * should be lost race to close(2) of sol.
3916 				 * The socket is about to soabort().
3917 				 */
3918 				SOCK_UNLOCK(so);
3919 				sorele_locked(head);
3920 				return;
3921 			}
3922 			last = refcount_release(&head->so_count);
3923 			KASSERT(!last, ("%s: released last reference for %p",
3924 			    __func__, head));
3925 		}
3926 again:
3927 		if ((so->so_options & SO_ACCEPTFILTER) == 0) {
3928 			TAILQ_REMOVE(&head->sol_incomp, so, so_list);
3929 			head->sol_incqlen--;
3930 			TAILQ_INSERT_TAIL(&head->sol_comp, so, so_list);
3931 			head->sol_qlen++;
3932 			so->so_qstate = SQ_COMP;
3933 			SOCK_UNLOCK(so);
3934 			solisten_wakeup(head);	/* unlocks */
3935 		} else {
3936 			SOCK_RECVBUF_LOCK(so);
3937 			soupcall_set(so, SO_RCV,
3938 			    head->sol_accept_filter->accf_callback,
3939 			    head->sol_accept_filter_arg);
3940 			so->so_options &= ~SO_ACCEPTFILTER;
3941 			ret = head->sol_accept_filter->accf_callback(so,
3942 			    head->sol_accept_filter_arg, M_NOWAIT);
3943 			if (ret == SU_ISCONNECTED) {
3944 				soupcall_clear(so, SO_RCV);
3945 				SOCK_RECVBUF_UNLOCK(so);
3946 				goto again;
3947 			}
3948 			SOCK_RECVBUF_UNLOCK(so);
3949 			SOCK_UNLOCK(so);
3950 			SOLISTEN_UNLOCK(head);
3951 		}
3952 		return;
3953 	}
3954 	SOCK_UNLOCK(so);
3955 	wakeup(&so->so_timeo);
3956 	sorwakeup(so);
3957 	sowwakeup(so);
3958 }
3959 
3960 void
3961 soisdisconnecting(struct socket *so)
3962 {
3963 
3964 	SOCK_LOCK(so);
3965 	so->so_state &= ~SS_ISCONNECTING;
3966 	so->so_state |= SS_ISDISCONNECTING;
3967 
3968 	if (!SOLISTENING(so)) {
3969 		SOCK_RECVBUF_LOCK(so);
3970 		socantrcvmore_locked(so);
3971 		SOCK_SENDBUF_LOCK(so);
3972 		socantsendmore_locked(so);
3973 	}
3974 	SOCK_UNLOCK(so);
3975 	wakeup(&so->so_timeo);
3976 }
3977 
3978 void
3979 soisdisconnected(struct socket *so)
3980 {
3981 
3982 	SOCK_LOCK(so);
3983 
3984 	/*
3985 	 * There is at least one reader of so_state that does not
3986 	 * acquire socket lock, namely soreceive_generic().  Ensure
3987 	 * that it never sees all flags that track connection status
3988 	 * cleared, by ordering the update with a barrier semantic of
3989 	 * our release thread fence.
3990 	 */
3991 	so->so_state |= SS_ISDISCONNECTED;
3992 	atomic_thread_fence_rel();
3993 	so->so_state &= ~(SS_ISCONNECTING|SS_ISCONNECTED|SS_ISDISCONNECTING);
3994 
3995 	if (!SOLISTENING(so)) {
3996 		SOCK_UNLOCK(so);
3997 		SOCK_RECVBUF_LOCK(so);
3998 		socantrcvmore_locked(so);
3999 		SOCK_SENDBUF_LOCK(so);
4000 		sbdrop_locked(&so->so_snd, sbused(&so->so_snd));
4001 		socantsendmore_locked(so);
4002 	} else
4003 		SOCK_UNLOCK(so);
4004 	wakeup(&so->so_timeo);
4005 }
4006 
4007 int
4008 soiolock(struct socket *so, struct sx *sx, int flags)
4009 {
4010 	int error;
4011 
4012 	KASSERT((flags & SBL_VALID) == flags,
4013 	    ("soiolock: invalid flags %#x", flags));
4014 
4015 	if ((flags & SBL_WAIT) != 0) {
4016 		if ((flags & SBL_NOINTR) != 0) {
4017 			sx_xlock(sx);
4018 		} else {
4019 			error = sx_xlock_sig(sx);
4020 			if (error != 0)
4021 				return (error);
4022 		}
4023 	} else if (!sx_try_xlock(sx)) {
4024 		return (EWOULDBLOCK);
4025 	}
4026 
4027 	if (__predict_false(SOLISTENING(so))) {
4028 		sx_xunlock(sx);
4029 		return (ENOTCONN);
4030 	}
4031 	return (0);
4032 }
4033 
4034 void
4035 soiounlock(struct sx *sx)
4036 {
4037 	sx_xunlock(sx);
4038 }
4039 
4040 /*
4041  * Make a copy of a sockaddr in a malloced buffer of type M_SONAME.
4042  */
4043 struct sockaddr *
4044 sodupsockaddr(const struct sockaddr *sa, int mflags)
4045 {
4046 	struct sockaddr *sa2;
4047 
4048 	sa2 = malloc(sa->sa_len, M_SONAME, mflags);
4049 	if (sa2)
4050 		bcopy(sa, sa2, sa->sa_len);
4051 	return sa2;
4052 }
4053 
4054 /*
4055  * Register per-socket destructor.
4056  */
4057 void
4058 sodtor_set(struct socket *so, so_dtor_t *func)
4059 {
4060 
4061 	SOCK_LOCK_ASSERT(so);
4062 	so->so_dtor = func;
4063 }
4064 
4065 /*
4066  * Register per-socket buffer upcalls.
4067  */
4068 void
4069 soupcall_set(struct socket *so, sb_which which, so_upcall_t func, void *arg)
4070 {
4071 	struct sockbuf *sb;
4072 
4073 	KASSERT(!SOLISTENING(so), ("%s: so %p listening", __func__, so));
4074 
4075 	switch (which) {
4076 	case SO_RCV:
4077 		sb = &so->so_rcv;
4078 		break;
4079 	case SO_SND:
4080 		sb = &so->so_snd;
4081 		break;
4082 	}
4083 	SOCK_BUF_LOCK_ASSERT(so, which);
4084 	sb->sb_upcall = func;
4085 	sb->sb_upcallarg = arg;
4086 	sb->sb_flags |= SB_UPCALL;
4087 }
4088 
4089 void
4090 soupcall_clear(struct socket *so, sb_which which)
4091 {
4092 	struct sockbuf *sb;
4093 
4094 	KASSERT(!SOLISTENING(so), ("%s: so %p listening", __func__, so));
4095 
4096 	switch (which) {
4097 	case SO_RCV:
4098 		sb = &so->so_rcv;
4099 		break;
4100 	case SO_SND:
4101 		sb = &so->so_snd;
4102 		break;
4103 	}
4104 	SOCK_BUF_LOCK_ASSERT(so, which);
4105 	KASSERT(sb->sb_upcall != NULL,
4106 	    ("%s: so %p no upcall to clear", __func__, so));
4107 	sb->sb_upcall = NULL;
4108 	sb->sb_upcallarg = NULL;
4109 	sb->sb_flags &= ~SB_UPCALL;
4110 }
4111 
4112 void
4113 solisten_upcall_set(struct socket *so, so_upcall_t func, void *arg)
4114 {
4115 
4116 	SOLISTEN_LOCK_ASSERT(so);
4117 	so->sol_upcall = func;
4118 	so->sol_upcallarg = arg;
4119 }
4120 
4121 static void
4122 so_rdknl_lock(void *arg)
4123 {
4124 	struct socket *so = arg;
4125 
4126 retry:
4127 	if (SOLISTENING(so)) {
4128 		SOLISTEN_LOCK(so);
4129 	} else {
4130 		SOCK_RECVBUF_LOCK(so);
4131 		if (__predict_false(SOLISTENING(so))) {
4132 			SOCK_RECVBUF_UNLOCK(so);
4133 			goto retry;
4134 		}
4135 	}
4136 }
4137 
4138 static void
4139 so_rdknl_unlock(void *arg)
4140 {
4141 	struct socket *so = arg;
4142 
4143 	if (SOLISTENING(so))
4144 		SOLISTEN_UNLOCK(so);
4145 	else
4146 		SOCK_RECVBUF_UNLOCK(so);
4147 }
4148 
4149 static void
4150 so_rdknl_assert_lock(void *arg, int what)
4151 {
4152 	struct socket *so = arg;
4153 
4154 	if (what == LA_LOCKED) {
4155 		if (SOLISTENING(so))
4156 			SOLISTEN_LOCK_ASSERT(so);
4157 		else
4158 			SOCK_RECVBUF_LOCK_ASSERT(so);
4159 	} else {
4160 		if (SOLISTENING(so))
4161 			SOLISTEN_UNLOCK_ASSERT(so);
4162 		else
4163 			SOCK_RECVBUF_UNLOCK_ASSERT(so);
4164 	}
4165 }
4166 
4167 static void
4168 so_wrknl_lock(void *arg)
4169 {
4170 	struct socket *so = arg;
4171 
4172 retry:
4173 	if (SOLISTENING(so)) {
4174 		SOLISTEN_LOCK(so);
4175 	} else {
4176 		SOCK_SENDBUF_LOCK(so);
4177 		if (__predict_false(SOLISTENING(so))) {
4178 			SOCK_SENDBUF_UNLOCK(so);
4179 			goto retry;
4180 		}
4181 	}
4182 }
4183 
4184 static void
4185 so_wrknl_unlock(void *arg)
4186 {
4187 	struct socket *so = arg;
4188 
4189 	if (SOLISTENING(so))
4190 		SOLISTEN_UNLOCK(so);
4191 	else
4192 		SOCK_SENDBUF_UNLOCK(so);
4193 }
4194 
4195 static void
4196 so_wrknl_assert_lock(void *arg, int what)
4197 {
4198 	struct socket *so = arg;
4199 
4200 	if (what == LA_LOCKED) {
4201 		if (SOLISTENING(so))
4202 			SOLISTEN_LOCK_ASSERT(so);
4203 		else
4204 			SOCK_SENDBUF_LOCK_ASSERT(so);
4205 	} else {
4206 		if (SOLISTENING(so))
4207 			SOLISTEN_UNLOCK_ASSERT(so);
4208 		else
4209 			SOCK_SENDBUF_UNLOCK_ASSERT(so);
4210 	}
4211 }
4212 
4213 /*
4214  * Create an external-format (``xsocket'') structure using the information in
4215  * the kernel-format socket structure pointed to by so.  This is done to
4216  * reduce the spew of irrelevant information over this interface, to isolate
4217  * user code from changes in the kernel structure, and potentially to provide
4218  * information-hiding if we decide that some of this information should be
4219  * hidden from users.
4220  */
4221 void
4222 sotoxsocket(struct socket *so, struct xsocket *xso)
4223 {
4224 
4225 	bzero(xso, sizeof(*xso));
4226 	xso->xso_len = sizeof *xso;
4227 	xso->xso_so = (uintptr_t)so;
4228 	xso->so_type = so->so_type;
4229 	xso->so_options = so->so_options;
4230 	xso->so_linger = so->so_linger;
4231 	xso->so_state = so->so_state;
4232 	xso->so_pcb = (uintptr_t)so->so_pcb;
4233 	xso->xso_protocol = so->so_proto->pr_protocol;
4234 	xso->xso_family = so->so_proto->pr_domain->dom_family;
4235 	xso->so_timeo = so->so_timeo;
4236 	xso->so_error = so->so_error;
4237 	xso->so_uid = so->so_cred->cr_uid;
4238 	xso->so_pgid = so->so_sigio ? so->so_sigio->sio_pgid : 0;
4239 	if (SOLISTENING(so)) {
4240 		xso->so_qlen = so->sol_qlen;
4241 		xso->so_incqlen = so->sol_incqlen;
4242 		xso->so_qlimit = so->sol_qlimit;
4243 		xso->so_oobmark = 0;
4244 	} else {
4245 		xso->so_state |= so->so_qstate;
4246 		xso->so_qlen = xso->so_incqlen = xso->so_qlimit = 0;
4247 		xso->so_oobmark = so->so_oobmark;
4248 		sbtoxsockbuf(&so->so_snd, &xso->so_snd);
4249 		sbtoxsockbuf(&so->so_rcv, &xso->so_rcv);
4250 	}
4251 }
4252 
4253 struct sockbuf *
4254 so_sockbuf_rcv(struct socket *so)
4255 {
4256 
4257 	return (&so->so_rcv);
4258 }
4259 
4260 struct sockbuf *
4261 so_sockbuf_snd(struct socket *so)
4262 {
4263 
4264 	return (&so->so_snd);
4265 }
4266 
4267 int
4268 so_state_get(const struct socket *so)
4269 {
4270 
4271 	return (so->so_state);
4272 }
4273 
4274 void
4275 so_state_set(struct socket *so, int val)
4276 {
4277 
4278 	so->so_state = val;
4279 }
4280 
4281 int
4282 so_options_get(const struct socket *so)
4283 {
4284 
4285 	return (so->so_options);
4286 }
4287 
4288 void
4289 so_options_set(struct socket *so, int val)
4290 {
4291 
4292 	so->so_options = val;
4293 }
4294 
4295 int
4296 so_error_get(const struct socket *so)
4297 {
4298 
4299 	return (so->so_error);
4300 }
4301 
4302 void
4303 so_error_set(struct socket *so, int val)
4304 {
4305 
4306 	so->so_error = val;
4307 }
4308 
4309 int
4310 so_linger_get(const struct socket *so)
4311 {
4312 
4313 	return (so->so_linger);
4314 }
4315 
4316 void
4317 so_linger_set(struct socket *so, int val)
4318 {
4319 
4320 	KASSERT(val >= 0 && val <= USHRT_MAX && val <= (INT_MAX / hz),
4321 	    ("%s: val %d out of range", __func__, val));
4322 
4323 	so->so_linger = val;
4324 }
4325 
4326 struct protosw *
4327 so_protosw_get(const struct socket *so)
4328 {
4329 
4330 	return (so->so_proto);
4331 }
4332 
4333 void
4334 so_protosw_set(struct socket *so, struct protosw *val)
4335 {
4336 
4337 	so->so_proto = val;
4338 }
4339 
4340 void
4341 so_sorwakeup(struct socket *so)
4342 {
4343 
4344 	sorwakeup(so);
4345 }
4346 
4347 void
4348 so_sowwakeup(struct socket *so)
4349 {
4350 
4351 	sowwakeup(so);
4352 }
4353 
4354 void
4355 so_sorwakeup_locked(struct socket *so)
4356 {
4357 
4358 	sorwakeup_locked(so);
4359 }
4360 
4361 void
4362 so_sowwakeup_locked(struct socket *so)
4363 {
4364 
4365 	sowwakeup_locked(so);
4366 }
4367 
4368 void
4369 so_lock(struct socket *so)
4370 {
4371 
4372 	SOCK_LOCK(so);
4373 }
4374 
4375 void
4376 so_unlock(struct socket *so)
4377 {
4378 
4379 	SOCK_UNLOCK(so);
4380 }
4381