xref: /freebsd/sys/kern/uipc_socket.c (revision 045c8f526484cb3b97f5fd693987f4376fa43c5f)
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  * accept_mtx locks down per-socket fields relating to accept queues.  See
256  * socketvar.h for an annotation of the protected fields of struct socket.
257  */
258 struct mtx accept_mtx;
259 MTX_SYSINIT(accept_mtx, &accept_mtx, "accept", MTX_DEF);
260 
261 /*
262  * so_global_mtx protects so_gencnt, numopensockets, and the per-socket
263  * so_gencnt field.
264  */
265 static struct mtx so_global_mtx;
266 MTX_SYSINIT(so_global_mtx, &so_global_mtx, "so_glabel", MTX_DEF);
267 
268 /*
269  * General IPC sysctl name space, used by sockets and a variety of other IPC
270  * types.
271  */
272 SYSCTL_NODE(_kern, KERN_IPC, ipc, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
273     "IPC");
274 
275 /*
276  * Initialize the socket subsystem and set up the socket
277  * memory allocator.
278  */
279 static uma_zone_t socket_zone;
280 int	maxsockets;
281 
282 static void
283 socket_zone_change(void *tag)
284 {
285 
286 	maxsockets = uma_zone_set_max(socket_zone, maxsockets);
287 }
288 
289 static void
290 socket_hhook_register(int subtype)
291 {
292 
293 	if (hhook_head_register(HHOOK_TYPE_SOCKET, subtype,
294 	    &V_socket_hhh[subtype],
295 	    HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0)
296 		printf("%s: WARNING: unable to register hook\n", __func__);
297 }
298 
299 static void
300 socket_hhook_deregister(int subtype)
301 {
302 
303 	if (hhook_head_deregister(V_socket_hhh[subtype]) != 0)
304 		printf("%s: WARNING: unable to deregister hook\n", __func__);
305 }
306 
307 static void
308 socket_init(void *tag)
309 {
310 
311 	socket_zone = uma_zcreate("socket", sizeof(struct socket), NULL, NULL,
312 	    NULL, NULL, UMA_ALIGN_PTR, 0);
313 	maxsockets = uma_zone_set_max(socket_zone, maxsockets);
314 	uma_zone_set_warning(socket_zone, "kern.ipc.maxsockets limit reached");
315 	EVENTHANDLER_REGISTER(maxsockets_change, socket_zone_change, NULL,
316 	    EVENTHANDLER_PRI_FIRST);
317 }
318 SYSINIT(socket, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY, socket_init, NULL);
319 
320 static void
321 socket_vnet_init(const void *unused __unused)
322 {
323 	int i;
324 
325 	/* We expect a contiguous range */
326 	for (i = 0; i <= HHOOK_SOCKET_LAST; i++)
327 		socket_hhook_register(i);
328 }
329 VNET_SYSINIT(socket_vnet_init, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY,
330     socket_vnet_init, NULL);
331 
332 static void
333 socket_vnet_uninit(const void *unused __unused)
334 {
335 	int i;
336 
337 	for (i = 0; i <= HHOOK_SOCKET_LAST; i++)
338 		socket_hhook_deregister(i);
339 }
340 VNET_SYSUNINIT(socket_vnet_uninit, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY,
341     socket_vnet_uninit, NULL);
342 
343 /*
344  * Initialise maxsockets.  This SYSINIT must be run after
345  * tunable_mbinit().
346  */
347 static void
348 init_maxsockets(void *ignored)
349 {
350 
351 	TUNABLE_INT_FETCH("kern.ipc.maxsockets", &maxsockets);
352 	maxsockets = imax(maxsockets, maxfiles);
353 }
354 SYSINIT(param, SI_SUB_TUNABLES, SI_ORDER_ANY, init_maxsockets, NULL);
355 
356 /*
357  * Sysctl to get and set the maximum global sockets limit.  Notify protocols
358  * of the change so that they can update their dependent limits as required.
359  */
360 static int
361 sysctl_maxsockets(SYSCTL_HANDLER_ARGS)
362 {
363 	int error, newmaxsockets;
364 
365 	newmaxsockets = maxsockets;
366 	error = sysctl_handle_int(oidp, &newmaxsockets, 0, req);
367 	if (error == 0 && req->newptr && newmaxsockets != maxsockets) {
368 		if (newmaxsockets > maxsockets &&
369 		    newmaxsockets <= maxfiles) {
370 			maxsockets = newmaxsockets;
371 			EVENTHANDLER_INVOKE(maxsockets_change);
372 		} else
373 			error = EINVAL;
374 	}
375 	return (error);
376 }
377 SYSCTL_PROC(_kern_ipc, OID_AUTO, maxsockets,
378     CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, &maxsockets, 0,
379     sysctl_maxsockets, "IU",
380     "Maximum number of sockets available");
381 
382 /*
383  * Socket operation routines.  These routines are called by the routines in
384  * sys_socket.c or from a system process, and implement the semantics of
385  * socket operations by switching out to the protocol specific routines.
386  */
387 
388 /*
389  * Get a socket structure from our zone, and initialize it.  Note that it
390  * would probably be better to allocate socket and PCB at the same time, but
391  * I'm not convinced that all the protocols can be easily modified to do
392  * this.
393  *
394  * soalloc() returns a socket with a ref count of 0.
395  */
396 static struct socket *
397 soalloc(struct vnet *vnet)
398 {
399 	struct socket *so;
400 
401 	so = uma_zalloc(socket_zone, M_NOWAIT | M_ZERO);
402 	if (so == NULL)
403 		return (NULL);
404 #ifdef MAC
405 	if (mac_socket_init(so, M_NOWAIT) != 0) {
406 		uma_zfree(socket_zone, so);
407 		return (NULL);
408 	}
409 #endif
410 	if (khelp_init_osd(HELPER_CLASS_SOCKET, &so->osd)) {
411 		uma_zfree(socket_zone, so);
412 		return (NULL);
413 	}
414 
415 	/*
416 	 * The socket locking protocol allows to lock 2 sockets at a time,
417 	 * however, the first one must be a listening socket.  WITNESS lacks
418 	 * a feature to change class of an existing lock, so we use DUPOK.
419 	 */
420 	mtx_init(&so->so_lock, "socket", NULL, MTX_DEF | MTX_DUPOK);
421 	so->so_snd.sb_mtx = &so->so_snd_mtx;
422 	so->so_rcv.sb_mtx = &so->so_rcv_mtx;
423 	SOCKBUF_LOCK_INIT(&so->so_snd, "so_snd");
424 	SOCKBUF_LOCK_INIT(&so->so_rcv, "so_rcv");
425 	so->so_rcv.sb_sel = &so->so_rdsel;
426 	so->so_snd.sb_sel = &so->so_wrsel;
427 	sx_init(&so->so_snd_sx, "so_snd_sx");
428 	sx_init(&so->so_rcv_sx, "so_rcv_sx");
429 	TAILQ_INIT(&so->so_snd.sb_aiojobq);
430 	TAILQ_INIT(&so->so_rcv.sb_aiojobq);
431 	TASK_INIT(&so->so_snd.sb_aiotask, 0, soaio_snd, so);
432 	TASK_INIT(&so->so_rcv.sb_aiotask, 0, soaio_rcv, so);
433 #ifdef VIMAGE
434 	VNET_ASSERT(vnet != NULL, ("%s:%d vnet is NULL, so=%p",
435 	    __func__, __LINE__, so));
436 	so->so_vnet = vnet;
437 #endif
438 	/* We shouldn't need the so_global_mtx */
439 	if (hhook_run_socket(so, NULL, HHOOK_SOCKET_CREATE)) {
440 		/* Do we need more comprehensive error returns? */
441 		uma_zfree(socket_zone, so);
442 		return (NULL);
443 	}
444 	mtx_lock(&so_global_mtx);
445 	so->so_gencnt = ++so_gencnt;
446 	++numopensockets;
447 #ifdef VIMAGE
448 	vnet->vnet_sockcnt++;
449 #endif
450 	mtx_unlock(&so_global_mtx);
451 
452 	return (so);
453 }
454 
455 /*
456  * Free the storage associated with a socket at the socket layer, tear down
457  * locks, labels, etc.  All protocol state is assumed already to have been
458  * torn down (and possibly never set up) by the caller.
459  */
460 static void
461 sodealloc(struct socket *so)
462 {
463 
464 	KASSERT(so->so_count == 0, ("sodealloc(): so_count %d", so->so_count));
465 	KASSERT(so->so_pcb == NULL, ("sodealloc(): so_pcb != NULL"));
466 
467 	mtx_lock(&so_global_mtx);
468 	so->so_gencnt = ++so_gencnt;
469 	--numopensockets;	/* Could be below, but faster here. */
470 #ifdef VIMAGE
471 	VNET_ASSERT(so->so_vnet != NULL, ("%s:%d so_vnet is NULL, so=%p",
472 	    __func__, __LINE__, so));
473 	so->so_vnet->vnet_sockcnt--;
474 #endif
475 	mtx_unlock(&so_global_mtx);
476 #ifdef MAC
477 	mac_socket_destroy(so);
478 #endif
479 	hhook_run_socket(so, NULL, HHOOK_SOCKET_CLOSE);
480 
481 	khelp_destroy_osd(&so->osd);
482 	if (SOLISTENING(so)) {
483 		if (so->sol_accept_filter != NULL)
484 			accept_filt_setopt(so, NULL);
485 	} else {
486 		if (so->so_rcv.sb_hiwat)
487 			(void)chgsbsize(so->so_cred->cr_uidinfo,
488 			    &so->so_rcv.sb_hiwat, 0, RLIM_INFINITY);
489 		if (so->so_snd.sb_hiwat)
490 			(void)chgsbsize(so->so_cred->cr_uidinfo,
491 			    &so->so_snd.sb_hiwat, 0, RLIM_INFINITY);
492 		sx_destroy(&so->so_snd_sx);
493 		sx_destroy(&so->so_rcv_sx);
494 		SOCKBUF_LOCK_DESTROY(&so->so_snd);
495 		SOCKBUF_LOCK_DESTROY(&so->so_rcv);
496 	}
497 	crfree(so->so_cred);
498 	mtx_destroy(&so->so_lock);
499 	uma_zfree(socket_zone, so);
500 }
501 
502 /*
503  * socreate returns a socket with a ref count of 1.  The socket should be
504  * closed with soclose().
505  */
506 int
507 socreate(int dom, struct socket **aso, int type, int proto,
508     struct ucred *cred, struct thread *td)
509 {
510 	struct protosw *prp;
511 	struct socket *so;
512 	int error;
513 
514 	if (proto)
515 		prp = pffindproto(dom, proto, type);
516 	else
517 		prp = pffindtype(dom, type);
518 
519 	if (prp == NULL) {
520 		/* No support for domain. */
521 		if (pffinddomain(dom) == NULL)
522 			return (EAFNOSUPPORT);
523 		/* No support for socket type. */
524 		if (proto == 0 && type != 0)
525 			return (EPROTOTYPE);
526 		return (EPROTONOSUPPORT);
527 	}
528 	if (prp->pr_usrreqs->pru_attach == NULL ||
529 	    prp->pr_usrreqs->pru_attach == pru_attach_notsupp)
530 		return (EPROTONOSUPPORT);
531 
532 	if (IN_CAPABILITY_MODE(td) && (prp->pr_flags & PR_CAPATTACH) == 0)
533 		return (ECAPMODE);
534 
535 	if (prison_check_af(cred, prp->pr_domain->dom_family) != 0)
536 		return (EPROTONOSUPPORT);
537 
538 	if (prp->pr_type != type)
539 		return (EPROTOTYPE);
540 	so = soalloc(CRED_TO_VNET(cred));
541 	if (so == NULL)
542 		return (ENOBUFS);
543 
544 	so->so_type = type;
545 	so->so_cred = crhold(cred);
546 	if ((prp->pr_domain->dom_family == PF_INET) ||
547 	    (prp->pr_domain->dom_family == PF_INET6) ||
548 	    (prp->pr_domain->dom_family == PF_ROUTE))
549 		so->so_fibnum = td->td_proc->p_fibnum;
550 	else
551 		so->so_fibnum = 0;
552 	so->so_proto = prp;
553 #ifdef MAC
554 	mac_socket_create(cred, so);
555 #endif
556 	knlist_init(&so->so_rdsel.si_note, so, so_rdknl_lock, so_rdknl_unlock,
557 	    so_rdknl_assert_lock);
558 	knlist_init(&so->so_wrsel.si_note, so, so_wrknl_lock, so_wrknl_unlock,
559 	    so_wrknl_assert_lock);
560 	/*
561 	 * Auto-sizing of socket buffers is managed by the protocols and
562 	 * the appropriate flags must be set in the pru_attach function.
563 	 */
564 	CURVNET_SET(so->so_vnet);
565 	error = (*prp->pr_usrreqs->pru_attach)(so, proto, td);
566 	CURVNET_RESTORE();
567 	if (error) {
568 		sodealloc(so);
569 		return (error);
570 	}
571 	soref(so);
572 	*aso = so;
573 	return (0);
574 }
575 
576 #ifdef REGRESSION
577 static int regression_sonewconn_earlytest = 1;
578 SYSCTL_INT(_regression, OID_AUTO, sonewconn_earlytest, CTLFLAG_RW,
579     &regression_sonewconn_earlytest, 0, "Perform early sonewconn limit test");
580 #endif
581 
582 static struct timeval overinterval = { 60, 0 };
583 SYSCTL_TIMEVAL_SEC(_kern_ipc, OID_AUTO, sooverinterval, CTLFLAG_RW,
584     &overinterval,
585     "Delay in seconds between warnings for listen socket overflows");
586 
587 /*
588  * When an attempt at a new connection is noted on a socket which accepts
589  * connections, sonewconn is called.  If the connection is possible (subject
590  * to space constraints, etc.) then we allocate a new structure, properly
591  * linked into the data structure of the original socket, and return this.
592  * Connstatus may be 0, or SS_ISCONFIRMING, or SS_ISCONNECTED.
593  *
594  * Note: the ref count on the socket is 0 on return.
595  */
596 struct socket *
597 sonewconn(struct socket *head, int connstatus)
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 			log(LOG_DEBUG,
703 			    "%s: pcb %p (%s): Listen queue overflow: "
704 			    "%i already in queue awaiting acceptance "
705 			    "(%d occurrences)\n",
706 			    __func__, head->so_pcb, sbuf_data(&descrsb),
707 			    qlen, overcount);
708 			sbuf_delete(&descrsb);
709 
710 			overcount = 0;
711 		}
712 
713 		return (NULL);
714 	}
715 	SOLISTEN_UNLOCK(head);
716 	VNET_ASSERT(head->so_vnet != NULL, ("%s: so %p vnet is NULL",
717 	    __func__, head));
718 	so = soalloc(head->so_vnet);
719 	if (so == NULL) {
720 		log(LOG_DEBUG, "%s: pcb %p: New socket allocation failure: "
721 		    "limit reached or out of memory\n",
722 		    __func__, head->so_pcb);
723 		return (NULL);
724 	}
725 	so->so_listen = head;
726 	so->so_type = head->so_type;
727 	so->so_options = head->so_options & ~SO_ACCEPTCONN;
728 	so->so_linger = head->so_linger;
729 	so->so_state = head->so_state | SS_NOFDREF;
730 	so->so_fibnum = head->so_fibnum;
731 	so->so_proto = head->so_proto;
732 	so->so_cred = crhold(head->so_cred);
733 #ifdef MAC
734 	mac_socket_newconn(head, so);
735 #endif
736 	knlist_init(&so->so_rdsel.si_note, so, so_rdknl_lock, so_rdknl_unlock,
737 	    so_rdknl_assert_lock);
738 	knlist_init(&so->so_wrsel.si_note, so, so_wrknl_lock, so_wrknl_unlock,
739 	    so_wrknl_assert_lock);
740 	VNET_SO_ASSERT(head);
741 	if (soreserve(so, head->sol_sbsnd_hiwat, head->sol_sbrcv_hiwat)) {
742 		sodealloc(so);
743 		log(LOG_DEBUG, "%s: pcb %p: soreserve() failed\n",
744 		    __func__, head->so_pcb);
745 		return (NULL);
746 	}
747 	if ((*so->so_proto->pr_usrreqs->pru_attach)(so, 0, NULL)) {
748 		sodealloc(so);
749 		log(LOG_DEBUG, "%s: pcb %p: pru_attach() failed\n",
750 		    __func__, head->so_pcb);
751 		return (NULL);
752 	}
753 	so->so_rcv.sb_lowat = head->sol_sbrcv_lowat;
754 	so->so_snd.sb_lowat = head->sol_sbsnd_lowat;
755 	so->so_rcv.sb_timeo = head->sol_sbrcv_timeo;
756 	so->so_snd.sb_timeo = head->sol_sbsnd_timeo;
757 	so->so_rcv.sb_flags |= head->sol_sbrcv_flags & SB_AUTOSIZE;
758 	so->so_snd.sb_flags |= head->sol_sbsnd_flags & SB_AUTOSIZE;
759 
760 	SOLISTEN_LOCK(head);
761 	if (head->sol_accept_filter != NULL)
762 		connstatus = 0;
763 	so->so_state |= connstatus;
764 	soref(head); /* A socket on (in)complete queue refs head. */
765 	if (connstatus) {
766 		TAILQ_INSERT_TAIL(&head->sol_comp, so, so_list);
767 		so->so_qstate = SQ_COMP;
768 		head->sol_qlen++;
769 		solisten_wakeup(head);	/* unlocks */
770 	} else {
771 		/*
772 		 * Keep removing sockets from the head until there's room for
773 		 * us to insert on the tail.  In pre-locking revisions, this
774 		 * was a simple if(), but as we could be racing with other
775 		 * threads and soabort() requires dropping locks, we must
776 		 * loop waiting for the condition to be true.
777 		 */
778 		while (head->sol_incqlen > head->sol_qlimit) {
779 			struct socket *sp;
780 
781 			sp = TAILQ_FIRST(&head->sol_incomp);
782 			TAILQ_REMOVE(&head->sol_incomp, sp, so_list);
783 			head->sol_incqlen--;
784 			SOCK_LOCK(sp);
785 			sp->so_qstate = SQ_NONE;
786 			sp->so_listen = NULL;
787 			SOCK_UNLOCK(sp);
788 			sorele_locked(head);	/* does SOLISTEN_UNLOCK, head stays */
789 			soabort(sp);
790 			SOLISTEN_LOCK(head);
791 		}
792 		TAILQ_INSERT_TAIL(&head->sol_incomp, so, so_list);
793 		so->so_qstate = SQ_INCOMP;
794 		head->sol_incqlen++;
795 		SOLISTEN_UNLOCK(head);
796 	}
797 	return (so);
798 }
799 
800 #if defined(SCTP) || defined(SCTP_SUPPORT)
801 /*
802  * Socket part of sctp_peeloff().  Detach a new socket from an
803  * association.  The new socket is returned with a reference.
804  */
805 struct socket *
806 sopeeloff(struct socket *head)
807 {
808 	struct socket *so;
809 
810 	VNET_ASSERT(head->so_vnet != NULL, ("%s:%d so_vnet is NULL, head=%p",
811 	    __func__, __LINE__, head));
812 	so = soalloc(head->so_vnet);
813 	if (so == NULL) {
814 		log(LOG_DEBUG, "%s: pcb %p: New socket allocation failure: "
815 		    "limit reached or out of memory\n",
816 		    __func__, head->so_pcb);
817 		return (NULL);
818 	}
819 	so->so_type = head->so_type;
820 	so->so_options = head->so_options;
821 	so->so_linger = head->so_linger;
822 	so->so_state = (head->so_state & SS_NBIO) | SS_ISCONNECTED;
823 	so->so_fibnum = head->so_fibnum;
824 	so->so_proto = head->so_proto;
825 	so->so_cred = crhold(head->so_cred);
826 #ifdef MAC
827 	mac_socket_newconn(head, so);
828 #endif
829 	knlist_init(&so->so_rdsel.si_note, so, so_rdknl_lock, so_rdknl_unlock,
830 	    so_rdknl_assert_lock);
831 	knlist_init(&so->so_wrsel.si_note, so, so_wrknl_lock, so_wrknl_unlock,
832 	    so_wrknl_assert_lock);
833 	VNET_SO_ASSERT(head);
834 	if (soreserve(so, head->so_snd.sb_hiwat, head->so_rcv.sb_hiwat)) {
835 		sodealloc(so);
836 		log(LOG_DEBUG, "%s: pcb %p: soreserve() failed\n",
837 		    __func__, head->so_pcb);
838 		return (NULL);
839 	}
840 	if ((*so->so_proto->pr_usrreqs->pru_attach)(so, 0, NULL)) {
841 		sodealloc(so);
842 		log(LOG_DEBUG, "%s: pcb %p: pru_attach() failed\n",
843 		    __func__, head->so_pcb);
844 		return (NULL);
845 	}
846 	so->so_rcv.sb_lowat = head->so_rcv.sb_lowat;
847 	so->so_snd.sb_lowat = head->so_snd.sb_lowat;
848 	so->so_rcv.sb_timeo = head->so_rcv.sb_timeo;
849 	so->so_snd.sb_timeo = head->so_snd.sb_timeo;
850 	so->so_rcv.sb_flags |= head->so_rcv.sb_flags & SB_AUTOSIZE;
851 	so->so_snd.sb_flags |= head->so_snd.sb_flags & SB_AUTOSIZE;
852 
853 	soref(so);
854 
855 	return (so);
856 }
857 #endif	/* SCTP */
858 
859 int
860 sobind(struct socket *so, struct sockaddr *nam, struct thread *td)
861 {
862 	int error;
863 
864 	CURVNET_SET(so->so_vnet);
865 	error = (*so->so_proto->pr_usrreqs->pru_bind)(so, nam, td);
866 	CURVNET_RESTORE();
867 	return (error);
868 }
869 
870 int
871 sobindat(int fd, struct socket *so, struct sockaddr *nam, struct thread *td)
872 {
873 	int error;
874 
875 	CURVNET_SET(so->so_vnet);
876 	error = (*so->so_proto->pr_usrreqs->pru_bindat)(fd, so, nam, td);
877 	CURVNET_RESTORE();
878 	return (error);
879 }
880 
881 /*
882  * solisten() transitions a socket from a non-listening state to a listening
883  * state, but can also be used to update the listen queue depth on an
884  * existing listen socket.  The protocol will call back into the sockets
885  * layer using solisten_proto_check() and solisten_proto() to check and set
886  * socket-layer listen state.  Call backs are used so that the protocol can
887  * acquire both protocol and socket layer locks in whatever order is required
888  * by the protocol.
889  *
890  * Protocol implementors are advised to hold the socket lock across the
891  * socket-layer test and set to avoid races at the socket layer.
892  */
893 int
894 solisten(struct socket *so, int backlog, struct thread *td)
895 {
896 	int error;
897 
898 	CURVNET_SET(so->so_vnet);
899 	error = (*so->so_proto->pr_usrreqs->pru_listen)(so, backlog, td);
900 	CURVNET_RESTORE();
901 	return (error);
902 }
903 
904 /*
905  * Prepare for a call to solisten_proto().  Acquire all socket buffer locks in
906  * order to interlock with socket I/O.
907  */
908 int
909 solisten_proto_check(struct socket *so)
910 {
911 	SOCK_LOCK_ASSERT(so);
912 
913 	if ((so->so_state & (SS_ISCONNECTED | SS_ISCONNECTING |
914 	    SS_ISDISCONNECTING)) != 0)
915 		return (EINVAL);
916 
917 	/*
918 	 * Sleeping is not permitted here, so simply fail if userspace is
919 	 * attempting to transmit or receive on the socket.  This kind of
920 	 * transient failure is not ideal, but it should occur only if userspace
921 	 * is misusing the socket interfaces.
922 	 */
923 	if (!sx_try_xlock(&so->so_snd_sx))
924 		return (EAGAIN);
925 	if (!sx_try_xlock(&so->so_rcv_sx)) {
926 		sx_xunlock(&so->so_snd_sx);
927 		return (EAGAIN);
928 	}
929 	mtx_lock(&so->so_snd_mtx);
930 	mtx_lock(&so->so_rcv_mtx);
931 
932 	/* Interlock with soo_aio_queue(). */
933 	if ((so->so_snd.sb_flags & (SB_AIO | SB_AIO_RUNNING)) != 0 ||
934 	   (so->so_rcv.sb_flags & (SB_AIO | SB_AIO_RUNNING)) != 0) {
935 		solisten_proto_abort(so);
936 		return (EINVAL);
937 	}
938 	return (0);
939 }
940 
941 /*
942  * Undo the setup done by solisten_proto_check().
943  */
944 void
945 solisten_proto_abort(struct socket *so)
946 {
947 	mtx_unlock(&so->so_snd_mtx);
948 	mtx_unlock(&so->so_rcv_mtx);
949 	sx_xunlock(&so->so_snd_sx);
950 	sx_xunlock(&so->so_rcv_sx);
951 }
952 
953 void
954 solisten_proto(struct socket *so, int backlog)
955 {
956 	int sbrcv_lowat, sbsnd_lowat;
957 	u_int sbrcv_hiwat, sbsnd_hiwat;
958 	short sbrcv_flags, sbsnd_flags;
959 	sbintime_t sbrcv_timeo, sbsnd_timeo;
960 
961 	SOCK_LOCK_ASSERT(so);
962 	KASSERT((so->so_state & (SS_ISCONNECTED | SS_ISCONNECTING |
963 	    SS_ISDISCONNECTING)) == 0,
964 	    ("%s: bad socket state %p", __func__, so));
965 
966 	if (SOLISTENING(so))
967 		goto listening;
968 
969 	/*
970 	 * Change this socket to listening state.
971 	 */
972 	sbrcv_lowat = so->so_rcv.sb_lowat;
973 	sbsnd_lowat = so->so_snd.sb_lowat;
974 	sbrcv_hiwat = so->so_rcv.sb_hiwat;
975 	sbsnd_hiwat = so->so_snd.sb_hiwat;
976 	sbrcv_flags = so->so_rcv.sb_flags;
977 	sbsnd_flags = so->so_snd.sb_flags;
978 	sbrcv_timeo = so->so_rcv.sb_timeo;
979 	sbsnd_timeo = so->so_snd.sb_timeo;
980 
981 	sbdestroy(&so->so_snd, so);
982 	sbdestroy(&so->so_rcv, so);
983 
984 #ifdef INVARIANTS
985 	bzero(&so->so_rcv,
986 	    sizeof(struct socket) - offsetof(struct socket, so_rcv));
987 #endif
988 
989 	so->sol_sbrcv_lowat = sbrcv_lowat;
990 	so->sol_sbsnd_lowat = sbsnd_lowat;
991 	so->sol_sbrcv_hiwat = sbrcv_hiwat;
992 	so->sol_sbsnd_hiwat = sbsnd_hiwat;
993 	so->sol_sbrcv_flags = sbrcv_flags;
994 	so->sol_sbsnd_flags = sbsnd_flags;
995 	so->sol_sbrcv_timeo = sbrcv_timeo;
996 	so->sol_sbsnd_timeo = sbsnd_timeo;
997 
998 	so->sol_qlen = so->sol_incqlen = 0;
999 	TAILQ_INIT(&so->sol_incomp);
1000 	TAILQ_INIT(&so->sol_comp);
1001 
1002 	so->sol_accept_filter = NULL;
1003 	so->sol_accept_filter_arg = NULL;
1004 	so->sol_accept_filter_str = NULL;
1005 
1006 	so->sol_upcall = NULL;
1007 	so->sol_upcallarg = NULL;
1008 
1009 	so->so_options |= SO_ACCEPTCONN;
1010 
1011 listening:
1012 	if (backlog < 0 || backlog > somaxconn)
1013 		backlog = somaxconn;
1014 	so->sol_qlimit = backlog;
1015 
1016 	mtx_unlock(&so->so_snd_mtx);
1017 	mtx_unlock(&so->so_rcv_mtx);
1018 	sx_xunlock(&so->so_snd_sx);
1019 	sx_xunlock(&so->so_rcv_sx);
1020 }
1021 
1022 /*
1023  * Wakeup listeners/subsystems once we have a complete connection.
1024  * Enters with lock, returns unlocked.
1025  */
1026 void
1027 solisten_wakeup(struct socket *sol)
1028 {
1029 
1030 	if (sol->sol_upcall != NULL)
1031 		(void )sol->sol_upcall(sol, sol->sol_upcallarg, M_NOWAIT);
1032 	else {
1033 		selwakeuppri(&sol->so_rdsel, PSOCK);
1034 		KNOTE_LOCKED(&sol->so_rdsel.si_note, 0);
1035 	}
1036 	SOLISTEN_UNLOCK(sol);
1037 	wakeup_one(&sol->sol_comp);
1038 	if ((sol->so_state & SS_ASYNC) && sol->so_sigio != NULL)
1039 		pgsigio(&sol->so_sigio, SIGIO, 0);
1040 }
1041 
1042 /*
1043  * Return single connection off a listening socket queue.  Main consumer of
1044  * the function is kern_accept4().  Some modules, that do their own accept
1045  * management also use the function.
1046  *
1047  * Listening socket must be locked on entry and is returned unlocked on
1048  * return.
1049  * The flags argument is set of accept4(2) flags and ACCEPT4_INHERIT.
1050  */
1051 int
1052 solisten_dequeue(struct socket *head, struct socket **ret, int flags)
1053 {
1054 	struct socket *so;
1055 	int error;
1056 
1057 	SOLISTEN_LOCK_ASSERT(head);
1058 
1059 	while (!(head->so_state & SS_NBIO) && TAILQ_EMPTY(&head->sol_comp) &&
1060 	    head->so_error == 0) {
1061 		error = msleep(&head->sol_comp, SOCK_MTX(head), PSOCK | PCATCH,
1062 		    "accept", 0);
1063 		if (error != 0) {
1064 			SOLISTEN_UNLOCK(head);
1065 			return (error);
1066 		}
1067 	}
1068 	if (head->so_error) {
1069 		error = head->so_error;
1070 		head->so_error = 0;
1071 	} else if ((head->so_state & SS_NBIO) && TAILQ_EMPTY(&head->sol_comp))
1072 		error = EWOULDBLOCK;
1073 	else
1074 		error = 0;
1075 	if (error) {
1076 		SOLISTEN_UNLOCK(head);
1077 		return (error);
1078 	}
1079 	so = TAILQ_FIRST(&head->sol_comp);
1080 	SOCK_LOCK(so);
1081 	KASSERT(so->so_qstate == SQ_COMP,
1082 	    ("%s: so %p not SQ_COMP", __func__, so));
1083 	soref(so);
1084 	head->sol_qlen--;
1085 	so->so_qstate = SQ_NONE;
1086 	so->so_listen = NULL;
1087 	TAILQ_REMOVE(&head->sol_comp, so, so_list);
1088 	if (flags & ACCEPT4_INHERIT)
1089 		so->so_state |= (head->so_state & SS_NBIO);
1090 	else
1091 		so->so_state |= (flags & SOCK_NONBLOCK) ? SS_NBIO : 0;
1092 	SOCK_UNLOCK(so);
1093 	sorele_locked(head);
1094 
1095 	*ret = so;
1096 	return (0);
1097 }
1098 
1099 /*
1100  * Evaluate the reference count and named references on a socket; if no
1101  * references remain, free it.  This should be called whenever a reference is
1102  * released, such as in sorele(), but also when named reference flags are
1103  * cleared in socket or protocol code.
1104  *
1105  * sofree() will free the socket if:
1106  *
1107  * - There are no outstanding file descriptor references or related consumers
1108  *   (so_count == 0).
1109  *
1110  * - The socket has been closed by user space, if ever open (SS_NOFDREF).
1111  *
1112  * - The protocol does not have an outstanding strong reference on the socket
1113  *   (SS_PROTOREF).
1114  *
1115  * - The socket is not in a completed connection queue, so a process has been
1116  *   notified that it is present.  If it is removed, the user process may
1117  *   block in accept() despite select() saying the socket was ready.
1118  */
1119 void
1120 sofree(struct socket *so)
1121 {
1122 	struct protosw *pr = so->so_proto;
1123 	bool last __diagused;
1124 
1125 	SOCK_LOCK_ASSERT(so);
1126 
1127 	if ((so->so_state & (SS_NOFDREF | SS_PROTOREF)) != SS_NOFDREF ||
1128 	    refcount_load(&so->so_count) != 0 || so->so_qstate == SQ_COMP) {
1129 		SOCK_UNLOCK(so);
1130 		return;
1131 	}
1132 
1133 	if (!SOLISTENING(so) && so->so_qstate == SQ_INCOMP) {
1134 		struct socket *sol;
1135 
1136 		sol = so->so_listen;
1137 		KASSERT(sol, ("%s: so %p on incomp of NULL", __func__, so));
1138 
1139 		/*
1140 		 * To solve race between close of a listening socket and
1141 		 * a socket on its incomplete queue, we need to lock both.
1142 		 * The order is first listening socket, then regular.
1143 		 * Since we don't have SS_NOFDREF neither SS_PROTOREF, this
1144 		 * function and the listening socket are the only pointers
1145 		 * to so.  To preserve so and sol, we reference both and then
1146 		 * relock.
1147 		 * After relock the socket may not move to so_comp since it
1148 		 * doesn't have PCB already, but it may be removed from
1149 		 * so_incomp. If that happens, we share responsiblity on
1150 		 * freeing the socket, but soclose() has already removed
1151 		 * it from queue.
1152 		 */
1153 		soref(sol);
1154 		soref(so);
1155 		SOCK_UNLOCK(so);
1156 		SOLISTEN_LOCK(sol);
1157 		SOCK_LOCK(so);
1158 		if (so->so_qstate == SQ_INCOMP) {
1159 			KASSERT(so->so_listen == sol,
1160 			    ("%s: so %p migrated out of sol %p",
1161 			    __func__, so, sol));
1162 			TAILQ_REMOVE(&sol->sol_incomp, so, so_list);
1163 			sol->sol_incqlen--;
1164 			last = refcount_release(&sol->so_count);
1165 			KASSERT(!last, ("%s: released last reference for %p",
1166 			    __func__, sol));
1167 			so->so_qstate = SQ_NONE;
1168 			so->so_listen = NULL;
1169 		} else
1170 			KASSERT(so->so_listen == NULL,
1171 			    ("%s: so %p not on (in)comp with so_listen",
1172 			    __func__, so));
1173 		sorele_locked(sol);
1174 		KASSERT(refcount_load(&so->so_count) == 1,
1175 		    ("%s: so %p count %u", __func__, so, so->so_count));
1176 		so->so_count = 0;
1177 	}
1178 	if (SOLISTENING(so))
1179 		so->so_error = ECONNABORTED;
1180 	SOCK_UNLOCK(so);
1181 
1182 	if (so->so_dtor != NULL)
1183 		so->so_dtor(so);
1184 
1185 	VNET_SO_ASSERT(so);
1186 	if (pr->pr_flags & PR_RIGHTS && pr->pr_domain->dom_dispose != NULL)
1187 		(*pr->pr_domain->dom_dispose)(so);
1188 	if (pr->pr_usrreqs->pru_detach != NULL)
1189 		(*pr->pr_usrreqs->pru_detach)(so);
1190 
1191 	/*
1192 	 * From this point on, we assume that no other references to this
1193 	 * socket exist anywhere else in the stack.  Therefore, no locks need
1194 	 * to be acquired or held.
1195 	 *
1196 	 * We used to do a lot of socket buffer and socket locking here, as
1197 	 * well as invoke sorflush() and perform wakeups.  The direct call to
1198 	 * dom_dispose() and sbdestroy() are an inlining of what was
1199 	 * necessary from sorflush().
1200 	 *
1201 	 * Notice that the socket buffer and kqueue state are torn down
1202 	 * before calling pru_detach.  This means that protocols shold not
1203 	 * assume they can perform socket wakeups, etc, in their detach code.
1204 	 */
1205 	if (!SOLISTENING(so)) {
1206 		sbdestroy(&so->so_snd, so);
1207 		sbdestroy(&so->so_rcv, so);
1208 	}
1209 	seldrain(&so->so_rdsel);
1210 	seldrain(&so->so_wrsel);
1211 	knlist_destroy(&so->so_rdsel.si_note);
1212 	knlist_destroy(&so->so_wrsel.si_note);
1213 	sodealloc(so);
1214 }
1215 
1216 /*
1217  * Release a reference on a socket while holding the socket lock.
1218  * Unlocks the socket lock before returning.
1219  */
1220 void
1221 sorele_locked(struct socket *so)
1222 {
1223 	SOCK_LOCK_ASSERT(so);
1224 	if (refcount_release(&so->so_count))
1225 		sofree(so);
1226 	else
1227 		SOCK_UNLOCK(so);
1228 }
1229 
1230 /*
1231  * Close a socket on last file table reference removal.  Initiate disconnect
1232  * if connected.  Free socket when disconnect complete.
1233  *
1234  * This function will sorele() the socket.  Note that soclose() may be called
1235  * prior to the ref count reaching zero.  The actual socket structure will
1236  * not be freed until the ref count reaches zero.
1237  */
1238 int
1239 soclose(struct socket *so)
1240 {
1241 	struct accept_queue lqueue;
1242 	int error = 0;
1243 	bool listening, last __diagused;
1244 
1245 	KASSERT(!(so->so_state & SS_NOFDREF), ("soclose: SS_NOFDREF on enter"));
1246 
1247 	CURVNET_SET(so->so_vnet);
1248 	funsetown(&so->so_sigio);
1249 	if (so->so_state & SS_ISCONNECTED) {
1250 		if ((so->so_state & SS_ISDISCONNECTING) == 0) {
1251 			error = sodisconnect(so);
1252 			if (error) {
1253 				if (error == ENOTCONN)
1254 					error = 0;
1255 				goto drop;
1256 			}
1257 		}
1258 
1259 		if ((so->so_options & SO_LINGER) != 0 && so->so_linger != 0) {
1260 			if ((so->so_state & SS_ISDISCONNECTING) &&
1261 			    (so->so_state & SS_NBIO))
1262 				goto drop;
1263 			while (so->so_state & SS_ISCONNECTED) {
1264 				error = tsleep(&so->so_timeo,
1265 				    PSOCK | PCATCH, "soclos",
1266 				    so->so_linger * hz);
1267 				if (error)
1268 					break;
1269 			}
1270 		}
1271 	}
1272 
1273 drop:
1274 	if (so->so_proto->pr_usrreqs->pru_close != NULL)
1275 		(*so->so_proto->pr_usrreqs->pru_close)(so);
1276 
1277 	SOCK_LOCK(so);
1278 	if ((listening = SOLISTENING(so))) {
1279 		struct socket *sp;
1280 
1281 		TAILQ_INIT(&lqueue);
1282 		TAILQ_SWAP(&lqueue, &so->sol_incomp, socket, so_list);
1283 		TAILQ_CONCAT(&lqueue, &so->sol_comp, so_list);
1284 
1285 		so->sol_qlen = so->sol_incqlen = 0;
1286 
1287 		TAILQ_FOREACH(sp, &lqueue, so_list) {
1288 			SOCK_LOCK(sp);
1289 			sp->so_qstate = SQ_NONE;
1290 			sp->so_listen = NULL;
1291 			SOCK_UNLOCK(sp);
1292 			last = refcount_release(&so->so_count);
1293 			KASSERT(!last, ("%s: released last reference for %p",
1294 			    __func__, so));
1295 		}
1296 	}
1297 	KASSERT((so->so_state & SS_NOFDREF) == 0, ("soclose: NOFDREF"));
1298 	so->so_state |= SS_NOFDREF;
1299 	sorele_locked(so);
1300 	if (listening) {
1301 		struct socket *sp, *tsp;
1302 
1303 		TAILQ_FOREACH_SAFE(sp, &lqueue, so_list, tsp) {
1304 			SOCK_LOCK(sp);
1305 			if (refcount_load(&sp->so_count) == 0) {
1306 				SOCK_UNLOCK(sp);
1307 				soabort(sp);
1308 			} else {
1309 				/* See the handling of queued sockets
1310 				   in sofree(). */
1311 				SOCK_UNLOCK(sp);
1312 			}
1313 		}
1314 	}
1315 	CURVNET_RESTORE();
1316 	return (error);
1317 }
1318 
1319 /*
1320  * soabort() is used to abruptly tear down a connection, such as when a
1321  * resource limit is reached (listen queue depth exceeded), or if a listen
1322  * socket is closed while there are sockets waiting to be accepted.
1323  *
1324  * This interface is tricky, because it is called on an unreferenced socket,
1325  * and must be called only by a thread that has actually removed the socket
1326  * from the listen queue it was on, or races with other threads are risked.
1327  *
1328  * This interface will call into the protocol code, so must not be called
1329  * with any socket locks held.  Protocols do call it while holding their own
1330  * recursible protocol mutexes, but this is something that should be subject
1331  * to review in the future.
1332  */
1333 void
1334 soabort(struct socket *so)
1335 {
1336 
1337 	/*
1338 	 * In as much as is possible, assert that no references to this
1339 	 * socket are held.  This is not quite the same as asserting that the
1340 	 * current thread is responsible for arranging for no references, but
1341 	 * is as close as we can get for now.
1342 	 */
1343 	KASSERT(so->so_count == 0, ("soabort: so_count"));
1344 	KASSERT((so->so_state & SS_PROTOREF) == 0, ("soabort: SS_PROTOREF"));
1345 	KASSERT(so->so_state & SS_NOFDREF, ("soabort: !SS_NOFDREF"));
1346 	VNET_SO_ASSERT(so);
1347 
1348 	if (so->so_proto->pr_usrreqs->pru_abort != NULL)
1349 		(*so->so_proto->pr_usrreqs->pru_abort)(so);
1350 	SOCK_LOCK(so);
1351 	sofree(so);
1352 }
1353 
1354 int
1355 soaccept(struct socket *so, struct sockaddr **nam)
1356 {
1357 	int error;
1358 
1359 	SOCK_LOCK(so);
1360 	KASSERT((so->so_state & SS_NOFDREF) != 0, ("soaccept: !NOFDREF"));
1361 	so->so_state &= ~SS_NOFDREF;
1362 	SOCK_UNLOCK(so);
1363 
1364 	CURVNET_SET(so->so_vnet);
1365 	error = (*so->so_proto->pr_usrreqs->pru_accept)(so, nam);
1366 	CURVNET_RESTORE();
1367 	return (error);
1368 }
1369 
1370 int
1371 soconnect(struct socket *so, struct sockaddr *nam, struct thread *td)
1372 {
1373 
1374 	return (soconnectat(AT_FDCWD, so, nam, td));
1375 }
1376 
1377 int
1378 soconnectat(int fd, struct socket *so, struct sockaddr *nam, struct thread *td)
1379 {
1380 	int error;
1381 
1382 	CURVNET_SET(so->so_vnet);
1383 	/*
1384 	 * If protocol is connection-based, can only connect once.
1385 	 * Otherwise, if connected, try to disconnect first.  This allows
1386 	 * user to disconnect by connecting to, e.g., a null address.
1387 	 */
1388 	if (so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING) &&
1389 	    ((so->so_proto->pr_flags & PR_CONNREQUIRED) ||
1390 	    (error = sodisconnect(so)))) {
1391 		error = EISCONN;
1392 	} else {
1393 		/*
1394 		 * Prevent accumulated error from previous connection from
1395 		 * biting us.
1396 		 */
1397 		so->so_error = 0;
1398 		if (fd == AT_FDCWD) {
1399 			error = (*so->so_proto->pr_usrreqs->pru_connect)(so,
1400 			    nam, td);
1401 		} else {
1402 			error = (*so->so_proto->pr_usrreqs->pru_connectat)(fd,
1403 			    so, nam, td);
1404 		}
1405 	}
1406 	CURVNET_RESTORE();
1407 
1408 	return (error);
1409 }
1410 
1411 int
1412 soconnect2(struct socket *so1, struct socket *so2)
1413 {
1414 	int error;
1415 
1416 	CURVNET_SET(so1->so_vnet);
1417 	error = (*so1->so_proto->pr_usrreqs->pru_connect2)(so1, so2);
1418 	CURVNET_RESTORE();
1419 	return (error);
1420 }
1421 
1422 int
1423 sodisconnect(struct socket *so)
1424 {
1425 	int error;
1426 
1427 	if ((so->so_state & SS_ISCONNECTED) == 0)
1428 		return (ENOTCONN);
1429 	if (so->so_state & SS_ISDISCONNECTING)
1430 		return (EALREADY);
1431 	VNET_SO_ASSERT(so);
1432 	error = (*so->so_proto->pr_usrreqs->pru_disconnect)(so);
1433 	return (error);
1434 }
1435 
1436 int
1437 sosend_dgram(struct socket *so, struct sockaddr *addr, struct uio *uio,
1438     struct mbuf *top, struct mbuf *control, int flags, struct thread *td)
1439 {
1440 	long space;
1441 	ssize_t resid;
1442 	int clen = 0, error, dontroute;
1443 
1444 	KASSERT(so->so_type == SOCK_DGRAM, ("sosend_dgram: !SOCK_DGRAM"));
1445 	KASSERT(so->so_proto->pr_flags & PR_ATOMIC,
1446 	    ("sosend_dgram: !PR_ATOMIC"));
1447 
1448 	if (uio != NULL)
1449 		resid = uio->uio_resid;
1450 	else
1451 		resid = top->m_pkthdr.len;
1452 	/*
1453 	 * In theory resid should be unsigned.  However, space must be
1454 	 * signed, as it might be less than 0 if we over-committed, and we
1455 	 * must use a signed comparison of space and resid.  On the other
1456 	 * hand, a negative resid causes us to loop sending 0-length
1457 	 * segments to the protocol.
1458 	 */
1459 	if (resid < 0) {
1460 		error = EINVAL;
1461 		goto out;
1462 	}
1463 
1464 	dontroute =
1465 	    (flags & MSG_DONTROUTE) && (so->so_options & SO_DONTROUTE) == 0;
1466 	if (td != NULL)
1467 		td->td_ru.ru_msgsnd++;
1468 	if (control != NULL)
1469 		clen = control->m_len;
1470 
1471 	SOCKBUF_LOCK(&so->so_snd);
1472 	if (so->so_snd.sb_state & SBS_CANTSENDMORE) {
1473 		SOCKBUF_UNLOCK(&so->so_snd);
1474 		error = EPIPE;
1475 		goto out;
1476 	}
1477 	if (so->so_error) {
1478 		error = so->so_error;
1479 		so->so_error = 0;
1480 		SOCKBUF_UNLOCK(&so->so_snd);
1481 		goto out;
1482 	}
1483 	if ((so->so_state & SS_ISCONNECTED) == 0) {
1484 		/*
1485 		 * `sendto' and `sendmsg' is allowed on a connection-based
1486 		 * socket if it supports implied connect.  Return ENOTCONN if
1487 		 * not connected and no address is supplied.
1488 		 */
1489 		if ((so->so_proto->pr_flags & PR_CONNREQUIRED) &&
1490 		    (so->so_proto->pr_flags & PR_IMPLOPCL) == 0) {
1491 			if ((so->so_state & SS_ISCONFIRMING) == 0 &&
1492 			    !(resid == 0 && clen != 0)) {
1493 				SOCKBUF_UNLOCK(&so->so_snd);
1494 				error = ENOTCONN;
1495 				goto out;
1496 			}
1497 		} else if (addr == NULL) {
1498 			if (so->so_proto->pr_flags & PR_CONNREQUIRED)
1499 				error = ENOTCONN;
1500 			else
1501 				error = EDESTADDRREQ;
1502 			SOCKBUF_UNLOCK(&so->so_snd);
1503 			goto out;
1504 		}
1505 	}
1506 
1507 	/*
1508 	 * Do we need MSG_OOB support in SOCK_DGRAM?  Signs here may be a
1509 	 * problem and need fixing.
1510 	 */
1511 	space = sbspace(&so->so_snd);
1512 	if (flags & MSG_OOB)
1513 		space += 1024;
1514 	space -= clen;
1515 	SOCKBUF_UNLOCK(&so->so_snd);
1516 	if (resid > space) {
1517 		error = EMSGSIZE;
1518 		goto out;
1519 	}
1520 	if (uio == NULL) {
1521 		resid = 0;
1522 		if (flags & MSG_EOR)
1523 			top->m_flags |= M_EOR;
1524 	} else {
1525 		/*
1526 		 * Copy the data from userland into a mbuf chain.
1527 		 * If no data is to be copied in, a single empty mbuf
1528 		 * is returned.
1529 		 */
1530 		top = m_uiotombuf(uio, M_WAITOK, space, max_hdr,
1531 		    (M_PKTHDR | ((flags & MSG_EOR) ? M_EOR : 0)));
1532 		if (top == NULL) {
1533 			error = EFAULT;	/* only possible error */
1534 			goto out;
1535 		}
1536 		space -= resid - uio->uio_resid;
1537 		resid = uio->uio_resid;
1538 	}
1539 	KASSERT(resid == 0, ("sosend_dgram: resid != 0"));
1540 	/*
1541 	 * XXXRW: Frobbing SO_DONTROUTE here is even worse without sblock
1542 	 * than with.
1543 	 */
1544 	if (dontroute) {
1545 		SOCK_LOCK(so);
1546 		so->so_options |= SO_DONTROUTE;
1547 		SOCK_UNLOCK(so);
1548 	}
1549 	/*
1550 	 * XXX all the SBS_CANTSENDMORE checks previously done could be out
1551 	 * of date.  We could have received a reset packet in an interrupt or
1552 	 * maybe we slept while doing page faults in uiomove() etc.  We could
1553 	 * probably recheck again inside the locking protection here, but
1554 	 * there are probably other places that this also happens.  We must
1555 	 * rethink this.
1556 	 */
1557 	VNET_SO_ASSERT(so);
1558 	error = (*so->so_proto->pr_usrreqs->pru_send)(so,
1559 	    (flags & MSG_OOB) ? PRUS_OOB :
1560 	/*
1561 	 * If the user set MSG_EOF, the protocol understands this flag and
1562 	 * nothing left to send then use PRU_SEND_EOF instead of PRU_SEND.
1563 	 */
1564 	    ((flags & MSG_EOF) &&
1565 	     (so->so_proto->pr_flags & PR_IMPLOPCL) &&
1566 	     (resid <= 0)) ?
1567 		PRUS_EOF :
1568 		/* If there is more to send set PRUS_MORETOCOME */
1569 		(flags & MSG_MORETOCOME) ||
1570 		(resid > 0 && space > 0) ? PRUS_MORETOCOME : 0,
1571 		top, addr, control, td);
1572 	if (dontroute) {
1573 		SOCK_LOCK(so);
1574 		so->so_options &= ~SO_DONTROUTE;
1575 		SOCK_UNLOCK(so);
1576 	}
1577 	clen = 0;
1578 	control = NULL;
1579 	top = NULL;
1580 out:
1581 	if (top != NULL)
1582 		m_freem(top);
1583 	if (control != NULL)
1584 		m_freem(control);
1585 	return (error);
1586 }
1587 
1588 /*
1589  * Send on a socket.  If send must go all at once and message is larger than
1590  * send buffering, then hard error.  Lock against other senders.  If must go
1591  * all at once and not enough room now, then inform user that this would
1592  * block and do nothing.  Otherwise, if nonblocking, send as much as
1593  * possible.  The data to be sent is described by "uio" if nonzero, otherwise
1594  * by the mbuf chain "top" (which must be null if uio is not).  Data provided
1595  * in mbuf chain must be small enough to send all at once.
1596  *
1597  * Returns nonzero on error, timeout or signal; callers must check for short
1598  * counts if EINTR/ERESTART are returned.  Data and control buffers are freed
1599  * on return.
1600  */
1601 int
1602 sosend_generic(struct socket *so, struct sockaddr *addr, struct uio *uio,
1603     struct mbuf *top, struct mbuf *control, int flags, struct thread *td)
1604 {
1605 	long space;
1606 	ssize_t resid;
1607 	int clen = 0, error, dontroute;
1608 	int atomic = sosendallatonce(so) || top;
1609 	int pru_flag;
1610 #ifdef KERN_TLS
1611 	struct ktls_session *tls;
1612 	int tls_enq_cnt, tls_pruflag;
1613 	uint8_t tls_rtype;
1614 
1615 	tls = NULL;
1616 	tls_rtype = TLS_RLTYPE_APP;
1617 #endif
1618 	if (uio != NULL)
1619 		resid = uio->uio_resid;
1620 	else if ((top->m_flags & M_PKTHDR) != 0)
1621 		resid = top->m_pkthdr.len;
1622 	else
1623 		resid = m_length(top, NULL);
1624 	/*
1625 	 * In theory resid should be unsigned.  However, space must be
1626 	 * signed, as it might be less than 0 if we over-committed, and we
1627 	 * must use a signed comparison of space and resid.  On the other
1628 	 * hand, a negative resid causes us to loop sending 0-length
1629 	 * segments to the protocol.
1630 	 *
1631 	 * Also check to make sure that MSG_EOR isn't used on SOCK_STREAM
1632 	 * type sockets since that's an error.
1633 	 */
1634 	if (resid < 0 || (so->so_type == SOCK_STREAM && (flags & MSG_EOR))) {
1635 		error = EINVAL;
1636 		goto out;
1637 	}
1638 
1639 	dontroute =
1640 	    (flags & MSG_DONTROUTE) && (so->so_options & SO_DONTROUTE) == 0 &&
1641 	    (so->so_proto->pr_flags & PR_ATOMIC);
1642 	if (td != NULL)
1643 		td->td_ru.ru_msgsnd++;
1644 	if (control != NULL)
1645 		clen = control->m_len;
1646 
1647 	error = SOCK_IO_SEND_LOCK(so, SBLOCKWAIT(flags));
1648 	if (error)
1649 		goto out;
1650 
1651 #ifdef KERN_TLS
1652 	tls_pruflag = 0;
1653 	tls = ktls_hold(so->so_snd.sb_tls_info);
1654 	if (tls != NULL) {
1655 		if (tls->mode == TCP_TLS_MODE_SW)
1656 			tls_pruflag = PRUS_NOTREADY;
1657 
1658 		if (control != NULL) {
1659 			struct cmsghdr *cm = mtod(control, struct cmsghdr *);
1660 
1661 			if (clen >= sizeof(*cm) &&
1662 			    cm->cmsg_type == TLS_SET_RECORD_TYPE) {
1663 				tls_rtype = *((uint8_t *)CMSG_DATA(cm));
1664 				clen = 0;
1665 				m_freem(control);
1666 				control = NULL;
1667 				atomic = 1;
1668 			}
1669 		}
1670 
1671 		if (resid == 0 && !ktls_permit_empty_frames(tls)) {
1672 			error = EINVAL;
1673 			goto release;
1674 		}
1675 	}
1676 #endif
1677 
1678 restart:
1679 	do {
1680 		SOCKBUF_LOCK(&so->so_snd);
1681 		if (so->so_snd.sb_state & SBS_CANTSENDMORE) {
1682 			SOCKBUF_UNLOCK(&so->so_snd);
1683 			error = EPIPE;
1684 			goto release;
1685 		}
1686 		if (so->so_error) {
1687 			error = so->so_error;
1688 			so->so_error = 0;
1689 			SOCKBUF_UNLOCK(&so->so_snd);
1690 			goto release;
1691 		}
1692 		if ((so->so_state & SS_ISCONNECTED) == 0) {
1693 			/*
1694 			 * `sendto' and `sendmsg' is allowed on a connection-
1695 			 * based socket if it supports implied connect.
1696 			 * Return ENOTCONN if not connected and no address is
1697 			 * supplied.
1698 			 */
1699 			if ((so->so_proto->pr_flags & PR_CONNREQUIRED) &&
1700 			    (so->so_proto->pr_flags & PR_IMPLOPCL) == 0) {
1701 				if ((so->so_state & SS_ISCONFIRMING) == 0 &&
1702 				    !(resid == 0 && clen != 0)) {
1703 					SOCKBUF_UNLOCK(&so->so_snd);
1704 					error = ENOTCONN;
1705 					goto release;
1706 				}
1707 			} else if (addr == NULL) {
1708 				SOCKBUF_UNLOCK(&so->so_snd);
1709 				if (so->so_proto->pr_flags & PR_CONNREQUIRED)
1710 					error = ENOTCONN;
1711 				else
1712 					error = EDESTADDRREQ;
1713 				goto release;
1714 			}
1715 		}
1716 		space = sbspace(&so->so_snd);
1717 		if (flags & MSG_OOB)
1718 			space += 1024;
1719 		if ((atomic && resid > so->so_snd.sb_hiwat) ||
1720 		    clen > so->so_snd.sb_hiwat) {
1721 			SOCKBUF_UNLOCK(&so->so_snd);
1722 			error = EMSGSIZE;
1723 			goto release;
1724 		}
1725 		if (space < resid + clen &&
1726 		    (atomic || space < so->so_snd.sb_lowat || space < clen)) {
1727 			if ((so->so_state & SS_NBIO) ||
1728 			    (flags & (MSG_NBIO | MSG_DONTWAIT)) != 0) {
1729 				SOCKBUF_UNLOCK(&so->so_snd);
1730 				error = EWOULDBLOCK;
1731 				goto release;
1732 			}
1733 			error = sbwait(&so->so_snd);
1734 			SOCKBUF_UNLOCK(&so->so_snd);
1735 			if (error)
1736 				goto release;
1737 			goto restart;
1738 		}
1739 		SOCKBUF_UNLOCK(&so->so_snd);
1740 		space -= clen;
1741 		do {
1742 			if (uio == NULL) {
1743 				resid = 0;
1744 				if (flags & MSG_EOR)
1745 					top->m_flags |= M_EOR;
1746 #ifdef KERN_TLS
1747 				if (tls != NULL) {
1748 					ktls_frame(top, tls, &tls_enq_cnt,
1749 					    tls_rtype);
1750 					tls_rtype = TLS_RLTYPE_APP;
1751 				}
1752 #endif
1753 			} else {
1754 				/*
1755 				 * Copy the data from userland into a mbuf
1756 				 * chain.  If resid is 0, which can happen
1757 				 * only if we have control to send, then
1758 				 * a single empty mbuf is returned.  This
1759 				 * is a workaround to prevent protocol send
1760 				 * methods to panic.
1761 				 */
1762 #ifdef KERN_TLS
1763 				if (tls != NULL) {
1764 					top = m_uiotombuf(uio, M_WAITOK, space,
1765 					    tls->params.max_frame_len,
1766 					    M_EXTPG |
1767 					    ((flags & MSG_EOR) ? M_EOR : 0));
1768 					if (top != NULL) {
1769 						ktls_frame(top, tls,
1770 						    &tls_enq_cnt, tls_rtype);
1771 					}
1772 					tls_rtype = TLS_RLTYPE_APP;
1773 				} else
1774 #endif
1775 					top = m_uiotombuf(uio, M_WAITOK, space,
1776 					    (atomic ? max_hdr : 0),
1777 					    (atomic ? M_PKTHDR : 0) |
1778 					    ((flags & MSG_EOR) ? M_EOR : 0));
1779 				if (top == NULL) {
1780 					error = EFAULT; /* only possible error */
1781 					goto release;
1782 				}
1783 				space -= resid - uio->uio_resid;
1784 				resid = uio->uio_resid;
1785 			}
1786 			if (dontroute) {
1787 				SOCK_LOCK(so);
1788 				so->so_options |= SO_DONTROUTE;
1789 				SOCK_UNLOCK(so);
1790 			}
1791 			/*
1792 			 * XXX all the SBS_CANTSENDMORE checks previously
1793 			 * done could be out of date.  We could have received
1794 			 * a reset packet in an interrupt or maybe we slept
1795 			 * while doing page faults in uiomove() etc.  We
1796 			 * could probably recheck again inside the locking
1797 			 * protection here, but there are probably other
1798 			 * places that this also happens.  We must rethink
1799 			 * this.
1800 			 */
1801 			VNET_SO_ASSERT(so);
1802 
1803 			pru_flag = (flags & MSG_OOB) ? PRUS_OOB :
1804 			/*
1805 			 * If the user set MSG_EOF, the protocol understands
1806 			 * this flag and nothing left to send then use
1807 			 * PRU_SEND_EOF instead of PRU_SEND.
1808 			 */
1809 			    ((flags & MSG_EOF) &&
1810 			     (so->so_proto->pr_flags & PR_IMPLOPCL) &&
1811 			     (resid <= 0)) ?
1812 				PRUS_EOF :
1813 			/* If there is more to send set PRUS_MORETOCOME. */
1814 			    (flags & MSG_MORETOCOME) ||
1815 			    (resid > 0 && space > 0) ? PRUS_MORETOCOME : 0;
1816 
1817 #ifdef KERN_TLS
1818 			pru_flag |= tls_pruflag;
1819 #endif
1820 
1821 			error = (*so->so_proto->pr_usrreqs->pru_send)(so,
1822 			    pru_flag, top, addr, control, td);
1823 
1824 			if (dontroute) {
1825 				SOCK_LOCK(so);
1826 				so->so_options &= ~SO_DONTROUTE;
1827 				SOCK_UNLOCK(so);
1828 			}
1829 
1830 #ifdef KERN_TLS
1831 			if (tls != NULL && tls->mode == TCP_TLS_MODE_SW) {
1832 				if (error != 0) {
1833 					m_freem(top);
1834 					top = NULL;
1835 				} else {
1836 					soref(so);
1837 					ktls_enqueue(top, so, tls_enq_cnt);
1838 				}
1839 			}
1840 #endif
1841 			clen = 0;
1842 			control = NULL;
1843 			top = NULL;
1844 			if (error)
1845 				goto release;
1846 		} while (resid && space > 0);
1847 	} while (resid);
1848 
1849 release:
1850 	SOCK_IO_SEND_UNLOCK(so);
1851 out:
1852 #ifdef KERN_TLS
1853 	if (tls != NULL)
1854 		ktls_free(tls);
1855 #endif
1856 	if (top != NULL)
1857 		m_freem(top);
1858 	if (control != NULL)
1859 		m_freem(control);
1860 	return (error);
1861 }
1862 
1863 int
1864 sosend(struct socket *so, struct sockaddr *addr, struct uio *uio,
1865     struct mbuf *top, struct mbuf *control, int flags, struct thread *td)
1866 {
1867 	int error;
1868 
1869 	CURVNET_SET(so->so_vnet);
1870 	error = so->so_proto->pr_usrreqs->pru_sosend(so, addr, uio,
1871 	    top, control, flags, td);
1872 	CURVNET_RESTORE();
1873 	return (error);
1874 }
1875 
1876 /*
1877  * The part of soreceive() that implements reading non-inline out-of-band
1878  * data from a socket.  For more complete comments, see soreceive(), from
1879  * which this code originated.
1880  *
1881  * Note that soreceive_rcvoob(), unlike the remainder of soreceive(), is
1882  * unable to return an mbuf chain to the caller.
1883  */
1884 static int
1885 soreceive_rcvoob(struct socket *so, struct uio *uio, int flags)
1886 {
1887 	struct protosw *pr = so->so_proto;
1888 	struct mbuf *m;
1889 	int error;
1890 
1891 	KASSERT(flags & MSG_OOB, ("soreceive_rcvoob: (flags & MSG_OOB) == 0"));
1892 	VNET_SO_ASSERT(so);
1893 
1894 	m = m_get(M_WAITOK, MT_DATA);
1895 	error = (*pr->pr_usrreqs->pru_rcvoob)(so, m, flags & MSG_PEEK);
1896 	if (error)
1897 		goto bad;
1898 	do {
1899 		error = uiomove(mtod(m, void *),
1900 		    (int) min(uio->uio_resid, m->m_len), uio);
1901 		m = m_free(m);
1902 	} while (uio->uio_resid && error == 0 && m);
1903 bad:
1904 	if (m != NULL)
1905 		m_freem(m);
1906 	return (error);
1907 }
1908 
1909 /*
1910  * Following replacement or removal of the first mbuf on the first mbuf chain
1911  * of a socket buffer, push necessary state changes back into the socket
1912  * buffer so that other consumers see the values consistently.  'nextrecord'
1913  * is the callers locally stored value of the original value of
1914  * sb->sb_mb->m_nextpkt which must be restored when the lead mbuf changes.
1915  * NOTE: 'nextrecord' may be NULL.
1916  */
1917 static __inline void
1918 sockbuf_pushsync(struct sockbuf *sb, struct mbuf *nextrecord)
1919 {
1920 
1921 	SOCKBUF_LOCK_ASSERT(sb);
1922 	/*
1923 	 * First, update for the new value of nextrecord.  If necessary, make
1924 	 * it the first record.
1925 	 */
1926 	if (sb->sb_mb != NULL)
1927 		sb->sb_mb->m_nextpkt = nextrecord;
1928 	else
1929 		sb->sb_mb = nextrecord;
1930 
1931 	/*
1932 	 * Now update any dependent socket buffer fields to reflect the new
1933 	 * state.  This is an expanded inline of SB_EMPTY_FIXUP(), with the
1934 	 * addition of a second clause that takes care of the case where
1935 	 * sb_mb has been updated, but remains the last record.
1936 	 */
1937 	if (sb->sb_mb == NULL) {
1938 		sb->sb_mbtail = NULL;
1939 		sb->sb_lastrecord = NULL;
1940 	} else if (sb->sb_mb->m_nextpkt == NULL)
1941 		sb->sb_lastrecord = sb->sb_mb;
1942 }
1943 
1944 /*
1945  * Implement receive operations on a socket.  We depend on the way that
1946  * records are added to the sockbuf by sbappend.  In particular, each record
1947  * (mbufs linked through m_next) must begin with an address if the protocol
1948  * so specifies, followed by an optional mbuf or mbufs containing ancillary
1949  * data, and then zero or more mbufs of data.  In order to allow parallelism
1950  * between network receive and copying to user space, as well as avoid
1951  * sleeping with a mutex held, we release the socket buffer mutex during the
1952  * user space copy.  Although the sockbuf is locked, new data may still be
1953  * appended, and thus we must maintain consistency of the sockbuf during that
1954  * time.
1955  *
1956  * The caller may receive the data as a single mbuf chain by supplying an
1957  * mbuf **mp0 for use in returning the chain.  The uio is then used only for
1958  * the count in uio_resid.
1959  */
1960 int
1961 soreceive_generic(struct socket *so, struct sockaddr **psa, struct uio *uio,
1962     struct mbuf **mp0, struct mbuf **controlp, int *flagsp)
1963 {
1964 	struct mbuf *m, **mp;
1965 	int flags, error, offset;
1966 	ssize_t len;
1967 	struct protosw *pr = so->so_proto;
1968 	struct mbuf *nextrecord;
1969 	int moff, type = 0;
1970 	ssize_t orig_resid = uio->uio_resid;
1971 
1972 	mp = mp0;
1973 	if (psa != NULL)
1974 		*psa = NULL;
1975 	if (controlp != NULL)
1976 		*controlp = NULL;
1977 	if (flagsp != NULL)
1978 		flags = *flagsp &~ MSG_EOR;
1979 	else
1980 		flags = 0;
1981 	if (flags & MSG_OOB)
1982 		return (soreceive_rcvoob(so, uio, flags));
1983 	if (mp != NULL)
1984 		*mp = NULL;
1985 	if ((pr->pr_flags & PR_WANTRCVD) && (so->so_state & SS_ISCONFIRMING)
1986 	    && uio->uio_resid) {
1987 		VNET_SO_ASSERT(so);
1988 		(*pr->pr_usrreqs->pru_rcvd)(so, 0);
1989 	}
1990 
1991 	error = SOCK_IO_RECV_LOCK(so, SBLOCKWAIT(flags));
1992 	if (error)
1993 		return (error);
1994 
1995 restart:
1996 	SOCKBUF_LOCK(&so->so_rcv);
1997 	m = so->so_rcv.sb_mb;
1998 	/*
1999 	 * If we have less data than requested, block awaiting more (subject
2000 	 * to any timeout) if:
2001 	 *   1. the current count is less than the low water mark, or
2002 	 *   2. MSG_DONTWAIT is not set
2003 	 */
2004 	if (m == NULL || (((flags & MSG_DONTWAIT) == 0 &&
2005 	    sbavail(&so->so_rcv) < uio->uio_resid) &&
2006 	    sbavail(&so->so_rcv) < so->so_rcv.sb_lowat &&
2007 	    m->m_nextpkt == NULL && (pr->pr_flags & PR_ATOMIC) == 0)) {
2008 		KASSERT(m != NULL || !sbavail(&so->so_rcv),
2009 		    ("receive: m == %p sbavail == %u",
2010 		    m, sbavail(&so->so_rcv)));
2011 		if (so->so_error || so->so_rerror) {
2012 			if (m != NULL)
2013 				goto dontblock;
2014 			if (so->so_error)
2015 				error = so->so_error;
2016 			else
2017 				error = so->so_rerror;
2018 			if ((flags & MSG_PEEK) == 0) {
2019 				if (so->so_error)
2020 					so->so_error = 0;
2021 				else
2022 					so->so_rerror = 0;
2023 			}
2024 			SOCKBUF_UNLOCK(&so->so_rcv);
2025 			goto release;
2026 		}
2027 		SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2028 		if (so->so_rcv.sb_state & SBS_CANTRCVMORE) {
2029 			if (m != NULL)
2030 				goto dontblock;
2031 #ifdef KERN_TLS
2032 			else if (so->so_rcv.sb_tlsdcc == 0 &&
2033 			    so->so_rcv.sb_tlscc == 0) {
2034 #else
2035 			else {
2036 #endif
2037 				SOCKBUF_UNLOCK(&so->so_rcv);
2038 				goto release;
2039 			}
2040 		}
2041 		for (; m != NULL; m = m->m_next)
2042 			if (m->m_type == MT_OOBDATA  || (m->m_flags & M_EOR)) {
2043 				m = so->so_rcv.sb_mb;
2044 				goto dontblock;
2045 			}
2046 		if ((so->so_state & (SS_ISCONNECTING | SS_ISCONNECTED |
2047 		    SS_ISDISCONNECTING | SS_ISDISCONNECTED)) == 0 &&
2048 		    (so->so_proto->pr_flags & PR_CONNREQUIRED) != 0) {
2049 			SOCKBUF_UNLOCK(&so->so_rcv);
2050 			error = ENOTCONN;
2051 			goto release;
2052 		}
2053 		if (uio->uio_resid == 0) {
2054 			SOCKBUF_UNLOCK(&so->so_rcv);
2055 			goto release;
2056 		}
2057 		if ((so->so_state & SS_NBIO) ||
2058 		    (flags & (MSG_DONTWAIT|MSG_NBIO))) {
2059 			SOCKBUF_UNLOCK(&so->so_rcv);
2060 			error = EWOULDBLOCK;
2061 			goto release;
2062 		}
2063 		SBLASTRECORDCHK(&so->so_rcv);
2064 		SBLASTMBUFCHK(&so->so_rcv);
2065 		error = sbwait(&so->so_rcv);
2066 		SOCKBUF_UNLOCK(&so->so_rcv);
2067 		if (error)
2068 			goto release;
2069 		goto restart;
2070 	}
2071 dontblock:
2072 	/*
2073 	 * From this point onward, we maintain 'nextrecord' as a cache of the
2074 	 * pointer to the next record in the socket buffer.  We must keep the
2075 	 * various socket buffer pointers and local stack versions of the
2076 	 * pointers in sync, pushing out modifications before dropping the
2077 	 * socket buffer mutex, and re-reading them when picking it up.
2078 	 *
2079 	 * Otherwise, we will race with the network stack appending new data
2080 	 * or records onto the socket buffer by using inconsistent/stale
2081 	 * versions of the field, possibly resulting in socket buffer
2082 	 * corruption.
2083 	 *
2084 	 * By holding the high-level sblock(), we prevent simultaneous
2085 	 * readers from pulling off the front of the socket buffer.
2086 	 */
2087 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2088 	if (uio->uio_td)
2089 		uio->uio_td->td_ru.ru_msgrcv++;
2090 	KASSERT(m == so->so_rcv.sb_mb, ("soreceive: m != so->so_rcv.sb_mb"));
2091 	SBLASTRECORDCHK(&so->so_rcv);
2092 	SBLASTMBUFCHK(&so->so_rcv);
2093 	nextrecord = m->m_nextpkt;
2094 	if (pr->pr_flags & PR_ADDR) {
2095 		KASSERT(m->m_type == MT_SONAME,
2096 		    ("m->m_type == %d", m->m_type));
2097 		orig_resid = 0;
2098 		if (psa != NULL)
2099 			*psa = sodupsockaddr(mtod(m, struct sockaddr *),
2100 			    M_NOWAIT);
2101 		if (flags & MSG_PEEK) {
2102 			m = m->m_next;
2103 		} else {
2104 			sbfree(&so->so_rcv, m);
2105 			so->so_rcv.sb_mb = m_free(m);
2106 			m = so->so_rcv.sb_mb;
2107 			sockbuf_pushsync(&so->so_rcv, nextrecord);
2108 		}
2109 	}
2110 
2111 	/*
2112 	 * Process one or more MT_CONTROL mbufs present before any data mbufs
2113 	 * in the first mbuf chain on the socket buffer.  If MSG_PEEK, we
2114 	 * just copy the data; if !MSG_PEEK, we call into the protocol to
2115 	 * perform externalization (or freeing if controlp == NULL).
2116 	 */
2117 	if (m != NULL && m->m_type == MT_CONTROL) {
2118 		struct mbuf *cm = NULL, *cmn;
2119 		struct mbuf **cme = &cm;
2120 #ifdef KERN_TLS
2121 		struct cmsghdr *cmsg;
2122 		struct tls_get_record tgr;
2123 
2124 		/*
2125 		 * For MSG_TLSAPPDATA, check for a non-application data
2126 		 * record.  If found, return ENXIO without removing
2127 		 * it from the receive queue.  This allows a subsequent
2128 		 * call without MSG_TLSAPPDATA to receive it.
2129 		 * Note that, for TLS, there should only be a single
2130 		 * control mbuf with the TLS_GET_RECORD message in it.
2131 		 */
2132 		if (flags & MSG_TLSAPPDATA) {
2133 			cmsg = mtod(m, struct cmsghdr *);
2134 			if (cmsg->cmsg_type == TLS_GET_RECORD &&
2135 			    cmsg->cmsg_len == CMSG_LEN(sizeof(tgr))) {
2136 				memcpy(&tgr, CMSG_DATA(cmsg), sizeof(tgr));
2137 				/* This will need to change for TLS 1.3. */
2138 				if (tgr.tls_type != TLS_RLTYPE_APP) {
2139 					SOCKBUF_UNLOCK(&so->so_rcv);
2140 					error = ENXIO;
2141 					goto release;
2142 				}
2143 			}
2144 		}
2145 #endif
2146 
2147 		do {
2148 			if (flags & MSG_PEEK) {
2149 				if (controlp != NULL) {
2150 					*controlp = m_copym(m, 0, m->m_len,
2151 					    M_NOWAIT);
2152 					controlp = &(*controlp)->m_next;
2153 				}
2154 				m = m->m_next;
2155 			} else {
2156 				sbfree(&so->so_rcv, m);
2157 				so->so_rcv.sb_mb = m->m_next;
2158 				m->m_next = NULL;
2159 				*cme = m;
2160 				cme = &(*cme)->m_next;
2161 				m = so->so_rcv.sb_mb;
2162 			}
2163 		} while (m != NULL && m->m_type == MT_CONTROL);
2164 		if ((flags & MSG_PEEK) == 0)
2165 			sockbuf_pushsync(&so->so_rcv, nextrecord);
2166 		while (cm != NULL) {
2167 			cmn = cm->m_next;
2168 			cm->m_next = NULL;
2169 			if (pr->pr_domain->dom_externalize != NULL) {
2170 				SOCKBUF_UNLOCK(&so->so_rcv);
2171 				VNET_SO_ASSERT(so);
2172 				error = (*pr->pr_domain->dom_externalize)
2173 				    (cm, controlp, flags);
2174 				SOCKBUF_LOCK(&so->so_rcv);
2175 			} else if (controlp != NULL)
2176 				*controlp = cm;
2177 			else
2178 				m_freem(cm);
2179 			if (controlp != NULL) {
2180 				while (*controlp != NULL)
2181 					controlp = &(*controlp)->m_next;
2182 			}
2183 			cm = cmn;
2184 		}
2185 		if (m != NULL)
2186 			nextrecord = so->so_rcv.sb_mb->m_nextpkt;
2187 		else
2188 			nextrecord = so->so_rcv.sb_mb;
2189 		orig_resid = 0;
2190 	}
2191 	if (m != NULL) {
2192 		if ((flags & MSG_PEEK) == 0) {
2193 			KASSERT(m->m_nextpkt == nextrecord,
2194 			    ("soreceive: post-control, nextrecord !sync"));
2195 			if (nextrecord == NULL) {
2196 				KASSERT(so->so_rcv.sb_mb == m,
2197 				    ("soreceive: post-control, sb_mb!=m"));
2198 				KASSERT(so->so_rcv.sb_lastrecord == m,
2199 				    ("soreceive: post-control, lastrecord!=m"));
2200 			}
2201 		}
2202 		type = m->m_type;
2203 		if (type == MT_OOBDATA)
2204 			flags |= MSG_OOB;
2205 	} else {
2206 		if ((flags & MSG_PEEK) == 0) {
2207 			KASSERT(so->so_rcv.sb_mb == nextrecord,
2208 			    ("soreceive: sb_mb != nextrecord"));
2209 			if (so->so_rcv.sb_mb == NULL) {
2210 				KASSERT(so->so_rcv.sb_lastrecord == NULL,
2211 				    ("soreceive: sb_lastercord != NULL"));
2212 			}
2213 		}
2214 	}
2215 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2216 	SBLASTRECORDCHK(&so->so_rcv);
2217 	SBLASTMBUFCHK(&so->so_rcv);
2218 
2219 	/*
2220 	 * Now continue to read any data mbufs off of the head of the socket
2221 	 * buffer until the read request is satisfied.  Note that 'type' is
2222 	 * used to store the type of any mbuf reads that have happened so far
2223 	 * such that soreceive() can stop reading if the type changes, which
2224 	 * causes soreceive() to return only one of regular data and inline
2225 	 * out-of-band data in a single socket receive operation.
2226 	 */
2227 	moff = 0;
2228 	offset = 0;
2229 	while (m != NULL && !(m->m_flags & M_NOTAVAIL) && uio->uio_resid > 0
2230 	    && error == 0) {
2231 		/*
2232 		 * If the type of mbuf has changed since the last mbuf
2233 		 * examined ('type'), end the receive operation.
2234 		 */
2235 		SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2236 		if (m->m_type == MT_OOBDATA || m->m_type == MT_CONTROL) {
2237 			if (type != m->m_type)
2238 				break;
2239 		} else if (type == MT_OOBDATA)
2240 			break;
2241 		else
2242 		    KASSERT(m->m_type == MT_DATA,
2243 			("m->m_type == %d", m->m_type));
2244 		so->so_rcv.sb_state &= ~SBS_RCVATMARK;
2245 		len = uio->uio_resid;
2246 		if (so->so_oobmark && len > so->so_oobmark - offset)
2247 			len = so->so_oobmark - offset;
2248 		if (len > m->m_len - moff)
2249 			len = m->m_len - moff;
2250 		/*
2251 		 * If mp is set, just pass back the mbufs.  Otherwise copy
2252 		 * them out via the uio, then free.  Sockbuf must be
2253 		 * consistent here (points to current mbuf, it points to next
2254 		 * record) when we drop priority; we must note any additions
2255 		 * to the sockbuf when we block interrupts again.
2256 		 */
2257 		if (mp == NULL) {
2258 			SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2259 			SBLASTRECORDCHK(&so->so_rcv);
2260 			SBLASTMBUFCHK(&so->so_rcv);
2261 			SOCKBUF_UNLOCK(&so->so_rcv);
2262 			if ((m->m_flags & M_EXTPG) != 0)
2263 				error = m_unmapped_uiomove(m, moff, uio,
2264 				    (int)len);
2265 			else
2266 				error = uiomove(mtod(m, char *) + moff,
2267 				    (int)len, uio);
2268 			SOCKBUF_LOCK(&so->so_rcv);
2269 			if (error) {
2270 				/*
2271 				 * The MT_SONAME mbuf has already been removed
2272 				 * from the record, so it is necessary to
2273 				 * remove the data mbufs, if any, to preserve
2274 				 * the invariant in the case of PR_ADDR that
2275 				 * requires MT_SONAME mbufs at the head of
2276 				 * each record.
2277 				 */
2278 				if (pr->pr_flags & PR_ATOMIC &&
2279 				    ((flags & MSG_PEEK) == 0))
2280 					(void)sbdroprecord_locked(&so->so_rcv);
2281 				SOCKBUF_UNLOCK(&so->so_rcv);
2282 				goto release;
2283 			}
2284 		} else
2285 			uio->uio_resid -= len;
2286 		SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2287 		if (len == m->m_len - moff) {
2288 			if (m->m_flags & M_EOR)
2289 				flags |= MSG_EOR;
2290 			if (flags & MSG_PEEK) {
2291 				m = m->m_next;
2292 				moff = 0;
2293 			} else {
2294 				nextrecord = m->m_nextpkt;
2295 				sbfree(&so->so_rcv, m);
2296 				if (mp != NULL) {
2297 					m->m_nextpkt = NULL;
2298 					*mp = m;
2299 					mp = &m->m_next;
2300 					so->so_rcv.sb_mb = m = m->m_next;
2301 					*mp = NULL;
2302 				} else {
2303 					so->so_rcv.sb_mb = m_free(m);
2304 					m = so->so_rcv.sb_mb;
2305 				}
2306 				sockbuf_pushsync(&so->so_rcv, nextrecord);
2307 				SBLASTRECORDCHK(&so->so_rcv);
2308 				SBLASTMBUFCHK(&so->so_rcv);
2309 			}
2310 		} else {
2311 			if (flags & MSG_PEEK)
2312 				moff += len;
2313 			else {
2314 				if (mp != NULL) {
2315 					if (flags & MSG_DONTWAIT) {
2316 						*mp = m_copym(m, 0, len,
2317 						    M_NOWAIT);
2318 						if (*mp == NULL) {
2319 							/*
2320 							 * m_copym() couldn't
2321 							 * allocate an mbuf.
2322 							 * Adjust uio_resid back
2323 							 * (it was adjusted
2324 							 * down by len bytes,
2325 							 * which we didn't end
2326 							 * up "copying" over).
2327 							 */
2328 							uio->uio_resid += len;
2329 							break;
2330 						}
2331 					} else {
2332 						SOCKBUF_UNLOCK(&so->so_rcv);
2333 						*mp = m_copym(m, 0, len,
2334 						    M_WAITOK);
2335 						SOCKBUF_LOCK(&so->so_rcv);
2336 					}
2337 				}
2338 				sbcut_locked(&so->so_rcv, len);
2339 			}
2340 		}
2341 		SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2342 		if (so->so_oobmark) {
2343 			if ((flags & MSG_PEEK) == 0) {
2344 				so->so_oobmark -= len;
2345 				if (so->so_oobmark == 0) {
2346 					so->so_rcv.sb_state |= SBS_RCVATMARK;
2347 					break;
2348 				}
2349 			} else {
2350 				offset += len;
2351 				if (offset == so->so_oobmark)
2352 					break;
2353 			}
2354 		}
2355 		if (flags & MSG_EOR)
2356 			break;
2357 		/*
2358 		 * If the MSG_WAITALL flag is set (for non-atomic socket), we
2359 		 * must not quit until "uio->uio_resid == 0" or an error
2360 		 * termination.  If a signal/timeout occurs, return with a
2361 		 * short count but without error.  Keep sockbuf locked
2362 		 * against other readers.
2363 		 */
2364 		while (flags & MSG_WAITALL && m == NULL && uio->uio_resid > 0 &&
2365 		    !sosendallatonce(so) && nextrecord == NULL) {
2366 			SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2367 			if (so->so_error || so->so_rerror ||
2368 			    so->so_rcv.sb_state & SBS_CANTRCVMORE)
2369 				break;
2370 			/*
2371 			 * Notify the protocol that some data has been
2372 			 * drained before blocking.
2373 			 */
2374 			if (pr->pr_flags & PR_WANTRCVD) {
2375 				SOCKBUF_UNLOCK(&so->so_rcv);
2376 				VNET_SO_ASSERT(so);
2377 				(*pr->pr_usrreqs->pru_rcvd)(so, flags);
2378 				SOCKBUF_LOCK(&so->so_rcv);
2379 			}
2380 			SBLASTRECORDCHK(&so->so_rcv);
2381 			SBLASTMBUFCHK(&so->so_rcv);
2382 			/*
2383 			 * We could receive some data while was notifying
2384 			 * the protocol. Skip blocking in this case.
2385 			 */
2386 			if (so->so_rcv.sb_mb == NULL) {
2387 				error = sbwait(&so->so_rcv);
2388 				if (error) {
2389 					SOCKBUF_UNLOCK(&so->so_rcv);
2390 					goto release;
2391 				}
2392 			}
2393 			m = so->so_rcv.sb_mb;
2394 			if (m != NULL)
2395 				nextrecord = m->m_nextpkt;
2396 		}
2397 	}
2398 
2399 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2400 	if (m != NULL && pr->pr_flags & PR_ATOMIC) {
2401 		flags |= MSG_TRUNC;
2402 		if ((flags & MSG_PEEK) == 0)
2403 			(void) sbdroprecord_locked(&so->so_rcv);
2404 	}
2405 	if ((flags & MSG_PEEK) == 0) {
2406 		if (m == NULL) {
2407 			/*
2408 			 * First part is an inline SB_EMPTY_FIXUP().  Second
2409 			 * part makes sure sb_lastrecord is up-to-date if
2410 			 * there is still data in the socket buffer.
2411 			 */
2412 			so->so_rcv.sb_mb = nextrecord;
2413 			if (so->so_rcv.sb_mb == NULL) {
2414 				so->so_rcv.sb_mbtail = NULL;
2415 				so->so_rcv.sb_lastrecord = NULL;
2416 			} else if (nextrecord->m_nextpkt == NULL)
2417 				so->so_rcv.sb_lastrecord = nextrecord;
2418 		}
2419 		SBLASTRECORDCHK(&so->so_rcv);
2420 		SBLASTMBUFCHK(&so->so_rcv);
2421 		/*
2422 		 * If soreceive() is being done from the socket callback,
2423 		 * then don't need to generate ACK to peer to update window,
2424 		 * since ACK will be generated on return to TCP.
2425 		 */
2426 		if (!(flags & MSG_SOCALLBCK) &&
2427 		    (pr->pr_flags & PR_WANTRCVD)) {
2428 			SOCKBUF_UNLOCK(&so->so_rcv);
2429 			VNET_SO_ASSERT(so);
2430 			(*pr->pr_usrreqs->pru_rcvd)(so, flags);
2431 			SOCKBUF_LOCK(&so->so_rcv);
2432 		}
2433 	}
2434 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2435 	if (orig_resid == uio->uio_resid && orig_resid &&
2436 	    (flags & MSG_EOR) == 0 && (so->so_rcv.sb_state & SBS_CANTRCVMORE) == 0) {
2437 		SOCKBUF_UNLOCK(&so->so_rcv);
2438 		goto restart;
2439 	}
2440 	SOCKBUF_UNLOCK(&so->so_rcv);
2441 
2442 	if (flagsp != NULL)
2443 		*flagsp |= flags;
2444 release:
2445 	SOCK_IO_RECV_UNLOCK(so);
2446 	return (error);
2447 }
2448 
2449 /*
2450  * Optimized version of soreceive() for stream (TCP) sockets.
2451  */
2452 int
2453 soreceive_stream(struct socket *so, struct sockaddr **psa, struct uio *uio,
2454     struct mbuf **mp0, struct mbuf **controlp, int *flagsp)
2455 {
2456 	int len = 0, error = 0, flags, oresid;
2457 	struct sockbuf *sb;
2458 	struct mbuf *m, *n = NULL;
2459 
2460 	/* We only do stream sockets. */
2461 	if (so->so_type != SOCK_STREAM)
2462 		return (EINVAL);
2463 	if (psa != NULL)
2464 		*psa = NULL;
2465 	if (flagsp != NULL)
2466 		flags = *flagsp &~ MSG_EOR;
2467 	else
2468 		flags = 0;
2469 	if (controlp != NULL)
2470 		*controlp = NULL;
2471 	if (flags & MSG_OOB)
2472 		return (soreceive_rcvoob(so, uio, flags));
2473 	if (mp0 != NULL)
2474 		*mp0 = NULL;
2475 
2476 	sb = &so->so_rcv;
2477 
2478 #ifdef KERN_TLS
2479 	/*
2480 	 * KTLS store TLS records as records with a control message to
2481 	 * describe the framing.
2482 	 *
2483 	 * We check once here before acquiring locks to optimize the
2484 	 * common case.
2485 	 */
2486 	if (sb->sb_tls_info != NULL)
2487 		return (soreceive_generic(so, psa, uio, mp0, controlp,
2488 		    flagsp));
2489 #endif
2490 
2491 	/* Prevent other readers from entering the socket. */
2492 	error = SOCK_IO_RECV_LOCK(so, SBLOCKWAIT(flags));
2493 	if (error)
2494 		return (error);
2495 	SOCKBUF_LOCK(sb);
2496 
2497 #ifdef KERN_TLS
2498 	if (sb->sb_tls_info != NULL) {
2499 		SOCKBUF_UNLOCK(sb);
2500 		SOCK_IO_RECV_UNLOCK(so);
2501 		return (soreceive_generic(so, psa, uio, mp0, controlp,
2502 		    flagsp));
2503 	}
2504 #endif
2505 
2506 	/* Easy one, no space to copyout anything. */
2507 	if (uio->uio_resid == 0) {
2508 		error = EINVAL;
2509 		goto out;
2510 	}
2511 	oresid = uio->uio_resid;
2512 
2513 	/* We will never ever get anything unless we are or were connected. */
2514 	if (!(so->so_state & (SS_ISCONNECTED|SS_ISDISCONNECTED))) {
2515 		error = ENOTCONN;
2516 		goto out;
2517 	}
2518 
2519 restart:
2520 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2521 
2522 	/* Abort if socket has reported problems. */
2523 	if (so->so_error) {
2524 		if (sbavail(sb) > 0)
2525 			goto deliver;
2526 		if (oresid > uio->uio_resid)
2527 			goto out;
2528 		error = so->so_error;
2529 		if (!(flags & MSG_PEEK))
2530 			so->so_error = 0;
2531 		goto out;
2532 	}
2533 
2534 	/* Door is closed.  Deliver what is left, if any. */
2535 	if (sb->sb_state & SBS_CANTRCVMORE) {
2536 		if (sbavail(sb) > 0)
2537 			goto deliver;
2538 		else
2539 			goto out;
2540 	}
2541 
2542 	/* Socket buffer is empty and we shall not block. */
2543 	if (sbavail(sb) == 0 &&
2544 	    ((so->so_state & SS_NBIO) || (flags & (MSG_DONTWAIT|MSG_NBIO)))) {
2545 		error = EAGAIN;
2546 		goto out;
2547 	}
2548 
2549 	/* Socket buffer got some data that we shall deliver now. */
2550 	if (sbavail(sb) > 0 && !(flags & MSG_WAITALL) &&
2551 	    ((so->so_state & SS_NBIO) ||
2552 	     (flags & (MSG_DONTWAIT|MSG_NBIO)) ||
2553 	     sbavail(sb) >= sb->sb_lowat ||
2554 	     sbavail(sb) >= uio->uio_resid ||
2555 	     sbavail(sb) >= sb->sb_hiwat) ) {
2556 		goto deliver;
2557 	}
2558 
2559 	/* On MSG_WAITALL we must wait until all data or error arrives. */
2560 	if ((flags & MSG_WAITALL) &&
2561 	    (sbavail(sb) >= uio->uio_resid || sbavail(sb) >= sb->sb_hiwat))
2562 		goto deliver;
2563 
2564 	/*
2565 	 * Wait and block until (more) data comes in.
2566 	 * NB: Drops the sockbuf lock during wait.
2567 	 */
2568 	error = sbwait(sb);
2569 	if (error)
2570 		goto out;
2571 	goto restart;
2572 
2573 deliver:
2574 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2575 	KASSERT(sbavail(sb) > 0, ("%s: sockbuf empty", __func__));
2576 	KASSERT(sb->sb_mb != NULL, ("%s: sb_mb == NULL", __func__));
2577 
2578 	/* Statistics. */
2579 	if (uio->uio_td)
2580 		uio->uio_td->td_ru.ru_msgrcv++;
2581 
2582 	/* Fill uio until full or current end of socket buffer is reached. */
2583 	len = min(uio->uio_resid, sbavail(sb));
2584 	if (mp0 != NULL) {
2585 		/* Dequeue as many mbufs as possible. */
2586 		if (!(flags & MSG_PEEK) && len >= sb->sb_mb->m_len) {
2587 			if (*mp0 == NULL)
2588 				*mp0 = sb->sb_mb;
2589 			else
2590 				m_cat(*mp0, sb->sb_mb);
2591 			for (m = sb->sb_mb;
2592 			     m != NULL && m->m_len <= len;
2593 			     m = m->m_next) {
2594 				KASSERT(!(m->m_flags & M_NOTAVAIL),
2595 				    ("%s: m %p not available", __func__, m));
2596 				len -= m->m_len;
2597 				uio->uio_resid -= m->m_len;
2598 				sbfree(sb, m);
2599 				n = m;
2600 			}
2601 			n->m_next = NULL;
2602 			sb->sb_mb = m;
2603 			sb->sb_lastrecord = sb->sb_mb;
2604 			if (sb->sb_mb == NULL)
2605 				SB_EMPTY_FIXUP(sb);
2606 		}
2607 		/* Copy the remainder. */
2608 		if (len > 0) {
2609 			KASSERT(sb->sb_mb != NULL,
2610 			    ("%s: len > 0 && sb->sb_mb empty", __func__));
2611 
2612 			m = m_copym(sb->sb_mb, 0, len, M_NOWAIT);
2613 			if (m == NULL)
2614 				len = 0;	/* Don't flush data from sockbuf. */
2615 			else
2616 				uio->uio_resid -= len;
2617 			if (*mp0 != NULL)
2618 				m_cat(*mp0, m);
2619 			else
2620 				*mp0 = m;
2621 			if (*mp0 == NULL) {
2622 				error = ENOBUFS;
2623 				goto out;
2624 			}
2625 		}
2626 	} else {
2627 		/* NB: Must unlock socket buffer as uiomove may sleep. */
2628 		SOCKBUF_UNLOCK(sb);
2629 		error = m_mbuftouio(uio, sb->sb_mb, len);
2630 		SOCKBUF_LOCK(sb);
2631 		if (error)
2632 			goto out;
2633 	}
2634 	SBLASTRECORDCHK(sb);
2635 	SBLASTMBUFCHK(sb);
2636 
2637 	/*
2638 	 * Remove the delivered data from the socket buffer unless we
2639 	 * were only peeking.
2640 	 */
2641 	if (!(flags & MSG_PEEK)) {
2642 		if (len > 0)
2643 			sbdrop_locked(sb, len);
2644 
2645 		/* Notify protocol that we drained some data. */
2646 		if ((so->so_proto->pr_flags & PR_WANTRCVD) &&
2647 		    (((flags & MSG_WAITALL) && uio->uio_resid > 0) ||
2648 		     !(flags & MSG_SOCALLBCK))) {
2649 			SOCKBUF_UNLOCK(sb);
2650 			VNET_SO_ASSERT(so);
2651 			(*so->so_proto->pr_usrreqs->pru_rcvd)(so, flags);
2652 			SOCKBUF_LOCK(sb);
2653 		}
2654 	}
2655 
2656 	/*
2657 	 * For MSG_WAITALL we may have to loop again and wait for
2658 	 * more data to come in.
2659 	 */
2660 	if ((flags & MSG_WAITALL) && uio->uio_resid > 0)
2661 		goto restart;
2662 out:
2663 	SBLASTRECORDCHK(sb);
2664 	SBLASTMBUFCHK(sb);
2665 	SOCKBUF_UNLOCK(sb);
2666 	SOCK_IO_RECV_UNLOCK(so);
2667 	return (error);
2668 }
2669 
2670 /*
2671  * Optimized version of soreceive() for simple datagram cases from userspace.
2672  * Unlike in the stream case, we're able to drop a datagram if copyout()
2673  * fails, and because we handle datagrams atomically, we don't need to use a
2674  * sleep lock to prevent I/O interlacing.
2675  */
2676 int
2677 soreceive_dgram(struct socket *so, struct sockaddr **psa, struct uio *uio,
2678     struct mbuf **mp0, struct mbuf **controlp, int *flagsp)
2679 {
2680 	struct mbuf *m, *m2;
2681 	int flags, error;
2682 	ssize_t len;
2683 	struct protosw *pr = so->so_proto;
2684 	struct mbuf *nextrecord;
2685 
2686 	if (psa != NULL)
2687 		*psa = NULL;
2688 	if (controlp != NULL)
2689 		*controlp = NULL;
2690 	if (flagsp != NULL)
2691 		flags = *flagsp &~ MSG_EOR;
2692 	else
2693 		flags = 0;
2694 
2695 	/*
2696 	 * For any complicated cases, fall back to the full
2697 	 * soreceive_generic().
2698 	 */
2699 	if (mp0 != NULL || (flags & MSG_PEEK) || (flags & MSG_OOB))
2700 		return (soreceive_generic(so, psa, uio, mp0, controlp,
2701 		    flagsp));
2702 
2703 	/*
2704 	 * Enforce restrictions on use.
2705 	 */
2706 	KASSERT((pr->pr_flags & PR_WANTRCVD) == 0,
2707 	    ("soreceive_dgram: wantrcvd"));
2708 	KASSERT(pr->pr_flags & PR_ATOMIC, ("soreceive_dgram: !atomic"));
2709 	KASSERT((so->so_rcv.sb_state & SBS_RCVATMARK) == 0,
2710 	    ("soreceive_dgram: SBS_RCVATMARK"));
2711 	KASSERT((so->so_proto->pr_flags & PR_CONNREQUIRED) == 0,
2712 	    ("soreceive_dgram: P_CONNREQUIRED"));
2713 
2714 	/*
2715 	 * Loop blocking while waiting for a datagram.
2716 	 */
2717 	SOCKBUF_LOCK(&so->so_rcv);
2718 	while ((m = so->so_rcv.sb_mb) == NULL) {
2719 		KASSERT(sbavail(&so->so_rcv) == 0,
2720 		    ("soreceive_dgram: sb_mb NULL but sbavail %u",
2721 		    sbavail(&so->so_rcv)));
2722 		if (so->so_error) {
2723 			error = so->so_error;
2724 			so->so_error = 0;
2725 			SOCKBUF_UNLOCK(&so->so_rcv);
2726 			return (error);
2727 		}
2728 		if (so->so_rcv.sb_state & SBS_CANTRCVMORE ||
2729 		    uio->uio_resid == 0) {
2730 			SOCKBUF_UNLOCK(&so->so_rcv);
2731 			return (0);
2732 		}
2733 		if ((so->so_state & SS_NBIO) ||
2734 		    (flags & (MSG_DONTWAIT|MSG_NBIO))) {
2735 			SOCKBUF_UNLOCK(&so->so_rcv);
2736 			return (EWOULDBLOCK);
2737 		}
2738 		SBLASTRECORDCHK(&so->so_rcv);
2739 		SBLASTMBUFCHK(&so->so_rcv);
2740 		error = sbwait(&so->so_rcv);
2741 		if (error) {
2742 			SOCKBUF_UNLOCK(&so->so_rcv);
2743 			return (error);
2744 		}
2745 	}
2746 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2747 
2748 	if (uio->uio_td)
2749 		uio->uio_td->td_ru.ru_msgrcv++;
2750 	SBLASTRECORDCHK(&so->so_rcv);
2751 	SBLASTMBUFCHK(&so->so_rcv);
2752 	nextrecord = m->m_nextpkt;
2753 	if (nextrecord == NULL) {
2754 		KASSERT(so->so_rcv.sb_lastrecord == m,
2755 		    ("soreceive_dgram: lastrecord != m"));
2756 	}
2757 
2758 	KASSERT(so->so_rcv.sb_mb->m_nextpkt == nextrecord,
2759 	    ("soreceive_dgram: m_nextpkt != nextrecord"));
2760 
2761 	/*
2762 	 * Pull 'm' and its chain off the front of the packet queue.
2763 	 */
2764 	so->so_rcv.sb_mb = NULL;
2765 	sockbuf_pushsync(&so->so_rcv, nextrecord);
2766 
2767 	/*
2768 	 * Walk 'm's chain and free that many bytes from the socket buffer.
2769 	 */
2770 	for (m2 = m; m2 != NULL; m2 = m2->m_next)
2771 		sbfree(&so->so_rcv, m2);
2772 
2773 	/*
2774 	 * Do a few last checks before we let go of the lock.
2775 	 */
2776 	SBLASTRECORDCHK(&so->so_rcv);
2777 	SBLASTMBUFCHK(&so->so_rcv);
2778 	SOCKBUF_UNLOCK(&so->so_rcv);
2779 
2780 	if (pr->pr_flags & PR_ADDR) {
2781 		KASSERT(m->m_type == MT_SONAME,
2782 		    ("m->m_type == %d", m->m_type));
2783 		if (psa != NULL)
2784 			*psa = sodupsockaddr(mtod(m, struct sockaddr *),
2785 			    M_NOWAIT);
2786 		m = m_free(m);
2787 	}
2788 	if (m == NULL) {
2789 		/* XXXRW: Can this happen? */
2790 		return (0);
2791 	}
2792 
2793 	/*
2794 	 * Packet to copyout() is now in 'm' and it is disconnected from the
2795 	 * queue.
2796 	 *
2797 	 * Process one or more MT_CONTROL mbufs present before any data mbufs
2798 	 * in the first mbuf chain on the socket buffer.  We call into the
2799 	 * protocol to perform externalization (or freeing if controlp ==
2800 	 * NULL). In some cases there can be only MT_CONTROL mbufs without
2801 	 * MT_DATA mbufs.
2802 	 */
2803 	if (m->m_type == MT_CONTROL) {
2804 		struct mbuf *cm = NULL, *cmn;
2805 		struct mbuf **cme = &cm;
2806 
2807 		do {
2808 			m2 = m->m_next;
2809 			m->m_next = NULL;
2810 			*cme = m;
2811 			cme = &(*cme)->m_next;
2812 			m = m2;
2813 		} while (m != NULL && m->m_type == MT_CONTROL);
2814 		while (cm != NULL) {
2815 			cmn = cm->m_next;
2816 			cm->m_next = NULL;
2817 			if (pr->pr_domain->dom_externalize != NULL) {
2818 				error = (*pr->pr_domain->dom_externalize)
2819 				    (cm, controlp, flags);
2820 			} else if (controlp != NULL)
2821 				*controlp = cm;
2822 			else
2823 				m_freem(cm);
2824 			if (controlp != NULL) {
2825 				while (*controlp != NULL)
2826 					controlp = &(*controlp)->m_next;
2827 			}
2828 			cm = cmn;
2829 		}
2830 	}
2831 	KASSERT(m == NULL || m->m_type == MT_DATA,
2832 	    ("soreceive_dgram: !data"));
2833 	while (m != NULL && uio->uio_resid > 0) {
2834 		len = uio->uio_resid;
2835 		if (len > m->m_len)
2836 			len = m->m_len;
2837 		error = uiomove(mtod(m, char *), (int)len, uio);
2838 		if (error) {
2839 			m_freem(m);
2840 			return (error);
2841 		}
2842 		if (len == m->m_len)
2843 			m = m_free(m);
2844 		else {
2845 			m->m_data += len;
2846 			m->m_len -= len;
2847 		}
2848 	}
2849 	if (m != NULL) {
2850 		flags |= MSG_TRUNC;
2851 		m_freem(m);
2852 	}
2853 	if (flagsp != NULL)
2854 		*flagsp |= flags;
2855 	return (0);
2856 }
2857 
2858 int
2859 soreceive(struct socket *so, struct sockaddr **psa, struct uio *uio,
2860     struct mbuf **mp0, struct mbuf **controlp, int *flagsp)
2861 {
2862 	int error;
2863 
2864 	CURVNET_SET(so->so_vnet);
2865 	error = (so->so_proto->pr_usrreqs->pru_soreceive(so, psa, uio,
2866 	    mp0, controlp, flagsp));
2867 	CURVNET_RESTORE();
2868 	return (error);
2869 }
2870 
2871 int
2872 soshutdown(struct socket *so, int how)
2873 {
2874 	struct protosw *pr;
2875 	int error, soerror_enotconn;
2876 
2877 	if (!(how == SHUT_RD || how == SHUT_WR || how == SHUT_RDWR))
2878 		return (EINVAL);
2879 
2880 	soerror_enotconn = 0;
2881 	SOCK_LOCK(so);
2882 	if ((so->so_state &
2883 	    (SS_ISCONNECTED | SS_ISCONNECTING | SS_ISDISCONNECTING)) == 0) {
2884 		/*
2885 		 * POSIX mandates us to return ENOTCONN when shutdown(2) is
2886 		 * invoked on a datagram sockets, however historically we would
2887 		 * actually tear socket down. This is known to be leveraged by
2888 		 * some applications to unblock process waiting in recvXXX(2)
2889 		 * by other process that it shares that socket with. Try to meet
2890 		 * both backward-compatibility and POSIX requirements by forcing
2891 		 * ENOTCONN but still asking protocol to perform pru_shutdown().
2892 		 */
2893 		if (so->so_type != SOCK_DGRAM && !SOLISTENING(so)) {
2894 			SOCK_UNLOCK(so);
2895 			return (ENOTCONN);
2896 		}
2897 		soerror_enotconn = 1;
2898 	}
2899 
2900 	if (SOLISTENING(so)) {
2901 		if (how != SHUT_WR) {
2902 			so->so_error = ECONNABORTED;
2903 			solisten_wakeup(so);	/* unlocks so */
2904 		} else {
2905 			SOCK_UNLOCK(so);
2906 		}
2907 		goto done;
2908 	}
2909 	SOCK_UNLOCK(so);
2910 
2911 	CURVNET_SET(so->so_vnet);
2912 	pr = so->so_proto;
2913 	if (pr->pr_usrreqs->pru_flush != NULL)
2914 		(*pr->pr_usrreqs->pru_flush)(so, how);
2915 	if (how != SHUT_WR)
2916 		sorflush(so);
2917 	if (how != SHUT_RD) {
2918 		error = (*pr->pr_usrreqs->pru_shutdown)(so);
2919 		wakeup(&so->so_timeo);
2920 		CURVNET_RESTORE();
2921 		return ((error == 0 && soerror_enotconn) ? ENOTCONN : error);
2922 	}
2923 	wakeup(&so->so_timeo);
2924 	CURVNET_RESTORE();
2925 
2926 done:
2927 	return (soerror_enotconn ? ENOTCONN : 0);
2928 }
2929 
2930 void
2931 sorflush(struct socket *so)
2932 {
2933 	struct socket aso;
2934 	struct protosw *pr;
2935 	int error;
2936 
2937 	VNET_SO_ASSERT(so);
2938 
2939 	/*
2940 	 * In order to avoid calling dom_dispose with the socket buffer mutex
2941 	 * held, we make a partial copy of the socket buffer and clear the
2942 	 * original.  The new socket buffer copy won't have initialized locks so
2943 	 * we can only call routines that won't use or assert those locks.
2944 	 * Ideally calling socantrcvmore() would prevent data from being added
2945 	 * to the buffer, but currently it merely prevents buffered data from
2946 	 * being read by userspace.  We make this effort to free buffered data
2947 	 * nonetheless.
2948 	 *
2949 	 * Dislodge threads currently blocked in receive and wait to acquire
2950 	 * a lock against other simultaneous readers before clearing the
2951 	 * socket buffer.  Don't let our acquire be interrupted by a signal
2952 	 * despite any existing socket disposition on interruptable waiting.
2953 	 */
2954 	socantrcvmore(so);
2955 
2956 	error = SOCK_IO_RECV_LOCK(so, SBL_WAIT | SBL_NOINTR);
2957 	if (error != 0) {
2958 		KASSERT(SOLISTENING(so),
2959 		    ("%s: soiolock(%p) failed", __func__, so));
2960 		return;
2961 	}
2962 
2963 	SOCK_RECVBUF_LOCK(so);
2964 	bzero(&aso, sizeof(aso));
2965 	aso.so_pcb = so->so_pcb;
2966 	bcopy(&so->so_rcv.sb_startzero, &aso.so_rcv.sb_startzero,
2967 	    offsetof(struct sockbuf, sb_endzero) -
2968 	    offsetof(struct sockbuf, sb_startzero));
2969 	bzero(&so->so_rcv.sb_startzero,
2970 	    offsetof(struct sockbuf, sb_endzero) -
2971 	    offsetof(struct sockbuf, sb_startzero));
2972 	SOCK_RECVBUF_UNLOCK(so);
2973 	SOCK_IO_RECV_UNLOCK(so);
2974 
2975 	/*
2976 	 * Dispose of special rights and flush the copied socket.  Don't call
2977 	 * any unsafe routines (that rely on locks being initialized) on aso.
2978 	 */
2979 	pr = so->so_proto;
2980 	if (pr->pr_flags & PR_RIGHTS && pr->pr_domain->dom_dispose != NULL)
2981 		(*pr->pr_domain->dom_dispose)(&aso);
2982 	sbrelease_internal(&aso.so_rcv, so);
2983 }
2984 
2985 /*
2986  * Wrapper for Socket established helper hook.
2987  * Parameters: socket, context of the hook point, hook id.
2988  */
2989 static int inline
2990 hhook_run_socket(struct socket *so, void *hctx, int32_t h_id)
2991 {
2992 	struct socket_hhook_data hhook_data = {
2993 		.so = so,
2994 		.hctx = hctx,
2995 		.m = NULL,
2996 		.status = 0
2997 	};
2998 
2999 	CURVNET_SET(so->so_vnet);
3000 	HHOOKS_RUN_IF(V_socket_hhh[h_id], &hhook_data, &so->osd);
3001 	CURVNET_RESTORE();
3002 
3003 	/* Ugly but needed, since hhooks return void for now */
3004 	return (hhook_data.status);
3005 }
3006 
3007 /*
3008  * Perhaps this routine, and sooptcopyout(), below, ought to come in an
3009  * additional variant to handle the case where the option value needs to be
3010  * some kind of integer, but not a specific size.  In addition to their use
3011  * here, these functions are also called by the protocol-level pr_ctloutput()
3012  * routines.
3013  */
3014 int
3015 sooptcopyin(struct sockopt *sopt, void *buf, size_t len, size_t minlen)
3016 {
3017 	size_t	valsize;
3018 
3019 	/*
3020 	 * If the user gives us more than we wanted, we ignore it, but if we
3021 	 * don't get the minimum length the caller wants, we return EINVAL.
3022 	 * On success, sopt->sopt_valsize is set to however much we actually
3023 	 * retrieved.
3024 	 */
3025 	if ((valsize = sopt->sopt_valsize) < minlen)
3026 		return EINVAL;
3027 	if (valsize > len)
3028 		sopt->sopt_valsize = valsize = len;
3029 
3030 	if (sopt->sopt_td != NULL)
3031 		return (copyin(sopt->sopt_val, buf, valsize));
3032 
3033 	bcopy(sopt->sopt_val, buf, valsize);
3034 	return (0);
3035 }
3036 
3037 /*
3038  * Kernel version of setsockopt(2).
3039  *
3040  * XXX: optlen is size_t, not socklen_t
3041  */
3042 int
3043 so_setsockopt(struct socket *so, int level, int optname, void *optval,
3044     size_t optlen)
3045 {
3046 	struct sockopt sopt;
3047 
3048 	sopt.sopt_level = level;
3049 	sopt.sopt_name = optname;
3050 	sopt.sopt_dir = SOPT_SET;
3051 	sopt.sopt_val = optval;
3052 	sopt.sopt_valsize = optlen;
3053 	sopt.sopt_td = NULL;
3054 	return (sosetopt(so, &sopt));
3055 }
3056 
3057 int
3058 sosetopt(struct socket *so, struct sockopt *sopt)
3059 {
3060 	int	error, optval;
3061 	struct	linger l;
3062 	struct	timeval tv;
3063 	sbintime_t val;
3064 	uint32_t val32;
3065 #ifdef MAC
3066 	struct mac extmac;
3067 #endif
3068 
3069 	CURVNET_SET(so->so_vnet);
3070 	error = 0;
3071 	if (sopt->sopt_level != SOL_SOCKET) {
3072 		if (so->so_proto->pr_ctloutput != NULL)
3073 			error = (*so->so_proto->pr_ctloutput)(so, sopt);
3074 		else
3075 			error = ENOPROTOOPT;
3076 	} else {
3077 		switch (sopt->sopt_name) {
3078 		case SO_ACCEPTFILTER:
3079 			error = accept_filt_setopt(so, sopt);
3080 			if (error)
3081 				goto bad;
3082 			break;
3083 
3084 		case SO_LINGER:
3085 			error = sooptcopyin(sopt, &l, sizeof l, sizeof l);
3086 			if (error)
3087 				goto bad;
3088 			if (l.l_linger < 0 ||
3089 			    l.l_linger > USHRT_MAX ||
3090 			    l.l_linger > (INT_MAX / hz)) {
3091 				error = EDOM;
3092 				goto bad;
3093 			}
3094 			SOCK_LOCK(so);
3095 			so->so_linger = l.l_linger;
3096 			if (l.l_onoff)
3097 				so->so_options |= SO_LINGER;
3098 			else
3099 				so->so_options &= ~SO_LINGER;
3100 			SOCK_UNLOCK(so);
3101 			break;
3102 
3103 		case SO_DEBUG:
3104 		case SO_KEEPALIVE:
3105 		case SO_DONTROUTE:
3106 		case SO_USELOOPBACK:
3107 		case SO_BROADCAST:
3108 		case SO_REUSEADDR:
3109 		case SO_REUSEPORT:
3110 		case SO_REUSEPORT_LB:
3111 		case SO_OOBINLINE:
3112 		case SO_TIMESTAMP:
3113 		case SO_BINTIME:
3114 		case SO_NOSIGPIPE:
3115 		case SO_NO_DDP:
3116 		case SO_NO_OFFLOAD:
3117 		case SO_RERROR:
3118 			error = sooptcopyin(sopt, &optval, sizeof optval,
3119 			    sizeof optval);
3120 			if (error)
3121 				goto bad;
3122 			SOCK_LOCK(so);
3123 			if (optval)
3124 				so->so_options |= sopt->sopt_name;
3125 			else
3126 				so->so_options &= ~sopt->sopt_name;
3127 			SOCK_UNLOCK(so);
3128 			break;
3129 
3130 		case SO_SETFIB:
3131 			error = sooptcopyin(sopt, &optval, sizeof optval,
3132 			    sizeof optval);
3133 			if (error)
3134 				goto bad;
3135 
3136 			if (optval < 0 || optval >= rt_numfibs) {
3137 				error = EINVAL;
3138 				goto bad;
3139 			}
3140 			if (((so->so_proto->pr_domain->dom_family == PF_INET) ||
3141 			   (so->so_proto->pr_domain->dom_family == PF_INET6) ||
3142 			   (so->so_proto->pr_domain->dom_family == PF_ROUTE)))
3143 				so->so_fibnum = optval;
3144 			else
3145 				so->so_fibnum = 0;
3146 			break;
3147 
3148 		case SO_USER_COOKIE:
3149 			error = sooptcopyin(sopt, &val32, sizeof val32,
3150 			    sizeof val32);
3151 			if (error)
3152 				goto bad;
3153 			so->so_user_cookie = val32;
3154 			break;
3155 
3156 		case SO_SNDBUF:
3157 		case SO_RCVBUF:
3158 		case SO_SNDLOWAT:
3159 		case SO_RCVLOWAT:
3160 			error = sooptcopyin(sopt, &optval, sizeof optval,
3161 			    sizeof optval);
3162 			if (error)
3163 				goto bad;
3164 
3165 			/*
3166 			 * Values < 1 make no sense for any of these options,
3167 			 * so disallow them.
3168 			 */
3169 			if (optval < 1) {
3170 				error = EINVAL;
3171 				goto bad;
3172 			}
3173 
3174 			error = sbsetopt(so, sopt->sopt_name, optval);
3175 			break;
3176 
3177 		case SO_SNDTIMEO:
3178 		case SO_RCVTIMEO:
3179 #ifdef COMPAT_FREEBSD32
3180 			if (SV_CURPROC_FLAG(SV_ILP32)) {
3181 				struct timeval32 tv32;
3182 
3183 				error = sooptcopyin(sopt, &tv32, sizeof tv32,
3184 				    sizeof tv32);
3185 				CP(tv32, tv, tv_sec);
3186 				CP(tv32, tv, tv_usec);
3187 			} else
3188 #endif
3189 				error = sooptcopyin(sopt, &tv, sizeof tv,
3190 				    sizeof tv);
3191 			if (error)
3192 				goto bad;
3193 			if (tv.tv_sec < 0 || tv.tv_usec < 0 ||
3194 			    tv.tv_usec >= 1000000) {
3195 				error = EDOM;
3196 				goto bad;
3197 			}
3198 			if (tv.tv_sec > INT32_MAX)
3199 				val = SBT_MAX;
3200 			else
3201 				val = tvtosbt(tv);
3202 			switch (sopt->sopt_name) {
3203 			case SO_SNDTIMEO:
3204 				so->so_snd.sb_timeo = val;
3205 				break;
3206 			case SO_RCVTIMEO:
3207 				so->so_rcv.sb_timeo = val;
3208 				break;
3209 			}
3210 			break;
3211 
3212 		case SO_LABEL:
3213 #ifdef MAC
3214 			error = sooptcopyin(sopt, &extmac, sizeof extmac,
3215 			    sizeof extmac);
3216 			if (error)
3217 				goto bad;
3218 			error = mac_setsockopt_label(sopt->sopt_td->td_ucred,
3219 			    so, &extmac);
3220 #else
3221 			error = EOPNOTSUPP;
3222 #endif
3223 			break;
3224 
3225 		case SO_TS_CLOCK:
3226 			error = sooptcopyin(sopt, &optval, sizeof optval,
3227 			    sizeof optval);
3228 			if (error)
3229 				goto bad;
3230 			if (optval < 0 || optval > SO_TS_CLOCK_MAX) {
3231 				error = EINVAL;
3232 				goto bad;
3233 			}
3234 			so->so_ts_clock = optval;
3235 			break;
3236 
3237 		case SO_MAX_PACING_RATE:
3238 			error = sooptcopyin(sopt, &val32, sizeof(val32),
3239 			    sizeof(val32));
3240 			if (error)
3241 				goto bad;
3242 			so->so_max_pacing_rate = val32;
3243 			break;
3244 
3245 		default:
3246 			if (V_socket_hhh[HHOOK_SOCKET_OPT]->hhh_nhooks > 0)
3247 				error = hhook_run_socket(so, sopt,
3248 				    HHOOK_SOCKET_OPT);
3249 			else
3250 				error = ENOPROTOOPT;
3251 			break;
3252 		}
3253 		if (error == 0 && so->so_proto->pr_ctloutput != NULL)
3254 			(void)(*so->so_proto->pr_ctloutput)(so, sopt);
3255 	}
3256 bad:
3257 	CURVNET_RESTORE();
3258 	return (error);
3259 }
3260 
3261 /*
3262  * Helper routine for getsockopt.
3263  */
3264 int
3265 sooptcopyout(struct sockopt *sopt, const void *buf, size_t len)
3266 {
3267 	int	error;
3268 	size_t	valsize;
3269 
3270 	error = 0;
3271 
3272 	/*
3273 	 * Documented get behavior is that we always return a value, possibly
3274 	 * truncated to fit in the user's buffer.  Traditional behavior is
3275 	 * that we always tell the user precisely how much we copied, rather
3276 	 * than something useful like the total amount we had available for
3277 	 * her.  Note that this interface is not idempotent; the entire
3278 	 * answer must be generated ahead of time.
3279 	 */
3280 	valsize = min(len, sopt->sopt_valsize);
3281 	sopt->sopt_valsize = valsize;
3282 	if (sopt->sopt_val != NULL) {
3283 		if (sopt->sopt_td != NULL)
3284 			error = copyout(buf, sopt->sopt_val, valsize);
3285 		else
3286 			bcopy(buf, sopt->sopt_val, valsize);
3287 	}
3288 	return (error);
3289 }
3290 
3291 int
3292 sogetopt(struct socket *so, struct sockopt *sopt)
3293 {
3294 	int	error, optval;
3295 	struct	linger l;
3296 	struct	timeval tv;
3297 #ifdef MAC
3298 	struct mac extmac;
3299 #endif
3300 
3301 	CURVNET_SET(so->so_vnet);
3302 	error = 0;
3303 	if (sopt->sopt_level != SOL_SOCKET) {
3304 		if (so->so_proto->pr_ctloutput != NULL)
3305 			error = (*so->so_proto->pr_ctloutput)(so, sopt);
3306 		else
3307 			error = ENOPROTOOPT;
3308 		CURVNET_RESTORE();
3309 		return (error);
3310 	} else {
3311 		switch (sopt->sopt_name) {
3312 		case SO_ACCEPTFILTER:
3313 			error = accept_filt_getopt(so, sopt);
3314 			break;
3315 
3316 		case SO_LINGER:
3317 			SOCK_LOCK(so);
3318 			l.l_onoff = so->so_options & SO_LINGER;
3319 			l.l_linger = so->so_linger;
3320 			SOCK_UNLOCK(so);
3321 			error = sooptcopyout(sopt, &l, sizeof l);
3322 			break;
3323 
3324 		case SO_USELOOPBACK:
3325 		case SO_DONTROUTE:
3326 		case SO_DEBUG:
3327 		case SO_KEEPALIVE:
3328 		case SO_REUSEADDR:
3329 		case SO_REUSEPORT:
3330 		case SO_REUSEPORT_LB:
3331 		case SO_BROADCAST:
3332 		case SO_OOBINLINE:
3333 		case SO_ACCEPTCONN:
3334 		case SO_TIMESTAMP:
3335 		case SO_BINTIME:
3336 		case SO_NOSIGPIPE:
3337 		case SO_NO_DDP:
3338 		case SO_NO_OFFLOAD:
3339 		case SO_RERROR:
3340 			optval = so->so_options & sopt->sopt_name;
3341 integer:
3342 			error = sooptcopyout(sopt, &optval, sizeof optval);
3343 			break;
3344 
3345 		case SO_DOMAIN:
3346 			optval = so->so_proto->pr_domain->dom_family;
3347 			goto integer;
3348 
3349 		case SO_TYPE:
3350 			optval = so->so_type;
3351 			goto integer;
3352 
3353 		case SO_PROTOCOL:
3354 			optval = so->so_proto->pr_protocol;
3355 			goto integer;
3356 
3357 		case SO_ERROR:
3358 			SOCK_LOCK(so);
3359 			if (so->so_error) {
3360 				optval = so->so_error;
3361 				so->so_error = 0;
3362 			} else {
3363 				optval = so->so_rerror;
3364 				so->so_rerror = 0;
3365 			}
3366 			SOCK_UNLOCK(so);
3367 			goto integer;
3368 
3369 		case SO_SNDBUF:
3370 			optval = SOLISTENING(so) ? so->sol_sbsnd_hiwat :
3371 			    so->so_snd.sb_hiwat;
3372 			goto integer;
3373 
3374 		case SO_RCVBUF:
3375 			optval = SOLISTENING(so) ? so->sol_sbrcv_hiwat :
3376 			    so->so_rcv.sb_hiwat;
3377 			goto integer;
3378 
3379 		case SO_SNDLOWAT:
3380 			optval = SOLISTENING(so) ? so->sol_sbsnd_lowat :
3381 			    so->so_snd.sb_lowat;
3382 			goto integer;
3383 
3384 		case SO_RCVLOWAT:
3385 			optval = SOLISTENING(so) ? so->sol_sbrcv_lowat :
3386 			    so->so_rcv.sb_lowat;
3387 			goto integer;
3388 
3389 		case SO_SNDTIMEO:
3390 		case SO_RCVTIMEO:
3391 			tv = sbttotv(sopt->sopt_name == SO_SNDTIMEO ?
3392 			    so->so_snd.sb_timeo : so->so_rcv.sb_timeo);
3393 #ifdef COMPAT_FREEBSD32
3394 			if (SV_CURPROC_FLAG(SV_ILP32)) {
3395 				struct timeval32 tv32;
3396 
3397 				CP(tv, tv32, tv_sec);
3398 				CP(tv, tv32, tv_usec);
3399 				error = sooptcopyout(sopt, &tv32, sizeof tv32);
3400 			} else
3401 #endif
3402 				error = sooptcopyout(sopt, &tv, sizeof tv);
3403 			break;
3404 
3405 		case SO_LABEL:
3406 #ifdef MAC
3407 			error = sooptcopyin(sopt, &extmac, sizeof(extmac),
3408 			    sizeof(extmac));
3409 			if (error)
3410 				goto bad;
3411 			error = mac_getsockopt_label(sopt->sopt_td->td_ucred,
3412 			    so, &extmac);
3413 			if (error)
3414 				goto bad;
3415 			error = sooptcopyout(sopt, &extmac, sizeof extmac);
3416 #else
3417 			error = EOPNOTSUPP;
3418 #endif
3419 			break;
3420 
3421 		case SO_PEERLABEL:
3422 #ifdef MAC
3423 			error = sooptcopyin(sopt, &extmac, sizeof(extmac),
3424 			    sizeof(extmac));
3425 			if (error)
3426 				goto bad;
3427 			error = mac_getsockopt_peerlabel(
3428 			    sopt->sopt_td->td_ucred, so, &extmac);
3429 			if (error)
3430 				goto bad;
3431 			error = sooptcopyout(sopt, &extmac, sizeof extmac);
3432 #else
3433 			error = EOPNOTSUPP;
3434 #endif
3435 			break;
3436 
3437 		case SO_LISTENQLIMIT:
3438 			optval = SOLISTENING(so) ? so->sol_qlimit : 0;
3439 			goto integer;
3440 
3441 		case SO_LISTENQLEN:
3442 			optval = SOLISTENING(so) ? so->sol_qlen : 0;
3443 			goto integer;
3444 
3445 		case SO_LISTENINCQLEN:
3446 			optval = SOLISTENING(so) ? so->sol_incqlen : 0;
3447 			goto integer;
3448 
3449 		case SO_TS_CLOCK:
3450 			optval = so->so_ts_clock;
3451 			goto integer;
3452 
3453 		case SO_MAX_PACING_RATE:
3454 			optval = so->so_max_pacing_rate;
3455 			goto integer;
3456 
3457 		default:
3458 			if (V_socket_hhh[HHOOK_SOCKET_OPT]->hhh_nhooks > 0)
3459 				error = hhook_run_socket(so, sopt,
3460 				    HHOOK_SOCKET_OPT);
3461 			else
3462 				error = ENOPROTOOPT;
3463 			break;
3464 		}
3465 	}
3466 #ifdef MAC
3467 bad:
3468 #endif
3469 	CURVNET_RESTORE();
3470 	return (error);
3471 }
3472 
3473 int
3474 soopt_getm(struct sockopt *sopt, struct mbuf **mp)
3475 {
3476 	struct mbuf *m, *m_prev;
3477 	int sopt_size = sopt->sopt_valsize;
3478 
3479 	MGET(m, sopt->sopt_td ? M_WAITOK : M_NOWAIT, MT_DATA);
3480 	if (m == NULL)
3481 		return ENOBUFS;
3482 	if (sopt_size > MLEN) {
3483 		MCLGET(m, sopt->sopt_td ? M_WAITOK : M_NOWAIT);
3484 		if ((m->m_flags & M_EXT) == 0) {
3485 			m_free(m);
3486 			return ENOBUFS;
3487 		}
3488 		m->m_len = min(MCLBYTES, sopt_size);
3489 	} else {
3490 		m->m_len = min(MLEN, sopt_size);
3491 	}
3492 	sopt_size -= m->m_len;
3493 	*mp = m;
3494 	m_prev = m;
3495 
3496 	while (sopt_size) {
3497 		MGET(m, sopt->sopt_td ? M_WAITOK : M_NOWAIT, MT_DATA);
3498 		if (m == NULL) {
3499 			m_freem(*mp);
3500 			return ENOBUFS;
3501 		}
3502 		if (sopt_size > MLEN) {
3503 			MCLGET(m, sopt->sopt_td != NULL ? M_WAITOK :
3504 			    M_NOWAIT);
3505 			if ((m->m_flags & M_EXT) == 0) {
3506 				m_freem(m);
3507 				m_freem(*mp);
3508 				return ENOBUFS;
3509 			}
3510 			m->m_len = min(MCLBYTES, sopt_size);
3511 		} else {
3512 			m->m_len = min(MLEN, sopt_size);
3513 		}
3514 		sopt_size -= m->m_len;
3515 		m_prev->m_next = m;
3516 		m_prev = m;
3517 	}
3518 	return (0);
3519 }
3520 
3521 int
3522 soopt_mcopyin(struct sockopt *sopt, struct mbuf *m)
3523 {
3524 	struct mbuf *m0 = m;
3525 
3526 	if (sopt->sopt_val == NULL)
3527 		return (0);
3528 	while (m != NULL && sopt->sopt_valsize >= m->m_len) {
3529 		if (sopt->sopt_td != NULL) {
3530 			int error;
3531 
3532 			error = copyin(sopt->sopt_val, mtod(m, char *),
3533 			    m->m_len);
3534 			if (error != 0) {
3535 				m_freem(m0);
3536 				return(error);
3537 			}
3538 		} else
3539 			bcopy(sopt->sopt_val, mtod(m, char *), m->m_len);
3540 		sopt->sopt_valsize -= m->m_len;
3541 		sopt->sopt_val = (char *)sopt->sopt_val + m->m_len;
3542 		m = m->m_next;
3543 	}
3544 	if (m != NULL) /* should be allocated enoughly at ip6_sooptmcopyin() */
3545 		panic("ip6_sooptmcopyin");
3546 	return (0);
3547 }
3548 
3549 int
3550 soopt_mcopyout(struct sockopt *sopt, struct mbuf *m)
3551 {
3552 	struct mbuf *m0 = m;
3553 	size_t valsize = 0;
3554 
3555 	if (sopt->sopt_val == NULL)
3556 		return (0);
3557 	while (m != NULL && sopt->sopt_valsize >= m->m_len) {
3558 		if (sopt->sopt_td != NULL) {
3559 			int error;
3560 
3561 			error = copyout(mtod(m, char *), sopt->sopt_val,
3562 			    m->m_len);
3563 			if (error != 0) {
3564 				m_freem(m0);
3565 				return(error);
3566 			}
3567 		} else
3568 			bcopy(mtod(m, char *), sopt->sopt_val, m->m_len);
3569 		sopt->sopt_valsize -= m->m_len;
3570 		sopt->sopt_val = (char *)sopt->sopt_val + m->m_len;
3571 		valsize += m->m_len;
3572 		m = m->m_next;
3573 	}
3574 	if (m != NULL) {
3575 		/* enough soopt buffer should be given from user-land */
3576 		m_freem(m0);
3577 		return(EINVAL);
3578 	}
3579 	sopt->sopt_valsize = valsize;
3580 	return (0);
3581 }
3582 
3583 /*
3584  * sohasoutofband(): protocol notifies socket layer of the arrival of new
3585  * out-of-band data, which will then notify socket consumers.
3586  */
3587 void
3588 sohasoutofband(struct socket *so)
3589 {
3590 
3591 	if (so->so_sigio != NULL)
3592 		pgsigio(&so->so_sigio, SIGURG, 0);
3593 	selwakeuppri(&so->so_rdsel, PSOCK);
3594 }
3595 
3596 int
3597 sopoll(struct socket *so, int events, struct ucred *active_cred,
3598     struct thread *td)
3599 {
3600 
3601 	/*
3602 	 * We do not need to set or assert curvnet as long as everyone uses
3603 	 * sopoll_generic().
3604 	 */
3605 	return (so->so_proto->pr_usrreqs->pru_sopoll(so, events, active_cred,
3606 	    td));
3607 }
3608 
3609 int
3610 sopoll_generic(struct socket *so, int events, struct ucred *active_cred,
3611     struct thread *td)
3612 {
3613 	int revents;
3614 
3615 	SOCK_LOCK(so);
3616 	if (SOLISTENING(so)) {
3617 		if (!(events & (POLLIN | POLLRDNORM)))
3618 			revents = 0;
3619 		else if (!TAILQ_EMPTY(&so->sol_comp))
3620 			revents = events & (POLLIN | POLLRDNORM);
3621 		else if ((events & POLLINIGNEOF) == 0 && so->so_error)
3622 			revents = (events & (POLLIN | POLLRDNORM)) | POLLHUP;
3623 		else {
3624 			selrecord(td, &so->so_rdsel);
3625 			revents = 0;
3626 		}
3627 	} else {
3628 		revents = 0;
3629 		SOCKBUF_LOCK(&so->so_snd);
3630 		SOCKBUF_LOCK(&so->so_rcv);
3631 		if (events & (POLLIN | POLLRDNORM))
3632 			if (soreadabledata(so))
3633 				revents |= events & (POLLIN | POLLRDNORM);
3634 		if (events & (POLLOUT | POLLWRNORM))
3635 			if (sowriteable(so))
3636 				revents |= events & (POLLOUT | POLLWRNORM);
3637 		if (events & (POLLPRI | POLLRDBAND))
3638 			if (so->so_oobmark ||
3639 			    (so->so_rcv.sb_state & SBS_RCVATMARK))
3640 				revents |= events & (POLLPRI | POLLRDBAND);
3641 		if ((events & POLLINIGNEOF) == 0) {
3642 			if (so->so_rcv.sb_state & SBS_CANTRCVMORE) {
3643 				revents |= events & (POLLIN | POLLRDNORM);
3644 				if (so->so_snd.sb_state & SBS_CANTSENDMORE)
3645 					revents |= POLLHUP;
3646 			}
3647 		}
3648 		if (so->so_rcv.sb_state & SBS_CANTRCVMORE)
3649 			revents |= events & POLLRDHUP;
3650 		if (revents == 0) {
3651 			if (events &
3652 			    (POLLIN | POLLPRI | POLLRDNORM | POLLRDBAND | POLLRDHUP)) {
3653 				selrecord(td, &so->so_rdsel);
3654 				so->so_rcv.sb_flags |= SB_SEL;
3655 			}
3656 			if (events & (POLLOUT | POLLWRNORM)) {
3657 				selrecord(td, &so->so_wrsel);
3658 				so->so_snd.sb_flags |= SB_SEL;
3659 			}
3660 		}
3661 		SOCKBUF_UNLOCK(&so->so_rcv);
3662 		SOCKBUF_UNLOCK(&so->so_snd);
3663 	}
3664 	SOCK_UNLOCK(so);
3665 	return (revents);
3666 }
3667 
3668 int
3669 soo_kqfilter(struct file *fp, struct knote *kn)
3670 {
3671 	struct socket *so = kn->kn_fp->f_data;
3672 	struct sockbuf *sb;
3673 	struct knlist *knl;
3674 
3675 	switch (kn->kn_filter) {
3676 	case EVFILT_READ:
3677 		kn->kn_fop = &soread_filtops;
3678 		knl = &so->so_rdsel.si_note;
3679 		sb = &so->so_rcv;
3680 		break;
3681 	case EVFILT_WRITE:
3682 		kn->kn_fop = &sowrite_filtops;
3683 		knl = &so->so_wrsel.si_note;
3684 		sb = &so->so_snd;
3685 		break;
3686 	case EVFILT_EMPTY:
3687 		kn->kn_fop = &soempty_filtops;
3688 		knl = &so->so_wrsel.si_note;
3689 		sb = &so->so_snd;
3690 		break;
3691 	default:
3692 		return (EINVAL);
3693 	}
3694 
3695 	SOCK_LOCK(so);
3696 	if (SOLISTENING(so)) {
3697 		knlist_add(knl, kn, 1);
3698 	} else {
3699 		SOCKBUF_LOCK(sb);
3700 		knlist_add(knl, kn, 1);
3701 		sb->sb_flags |= SB_KNOTE;
3702 		SOCKBUF_UNLOCK(sb);
3703 	}
3704 	SOCK_UNLOCK(so);
3705 	return (0);
3706 }
3707 
3708 /*
3709  * Some routines that return EOPNOTSUPP for entry points that are not
3710  * supported by a protocol.  Fill in as needed.
3711  */
3712 int
3713 pru_accept_notsupp(struct socket *so, struct sockaddr **nam)
3714 {
3715 
3716 	return EOPNOTSUPP;
3717 }
3718 
3719 int
3720 pru_aio_queue_notsupp(struct socket *so, struct kaiocb *job)
3721 {
3722 
3723 	return EOPNOTSUPP;
3724 }
3725 
3726 int
3727 pru_attach_notsupp(struct socket *so, int proto, struct thread *td)
3728 {
3729 
3730 	return EOPNOTSUPP;
3731 }
3732 
3733 int
3734 pru_bind_notsupp(struct socket *so, struct sockaddr *nam, struct thread *td)
3735 {
3736 
3737 	return EOPNOTSUPP;
3738 }
3739 
3740 int
3741 pru_bindat_notsupp(int fd, struct socket *so, struct sockaddr *nam,
3742     struct thread *td)
3743 {
3744 
3745 	return EOPNOTSUPP;
3746 }
3747 
3748 int
3749 pru_connect_notsupp(struct socket *so, struct sockaddr *nam, struct thread *td)
3750 {
3751 
3752 	return EOPNOTSUPP;
3753 }
3754 
3755 int
3756 pru_connectat_notsupp(int fd, struct socket *so, struct sockaddr *nam,
3757     struct thread *td)
3758 {
3759 
3760 	return EOPNOTSUPP;
3761 }
3762 
3763 int
3764 pru_connect2_notsupp(struct socket *so1, struct socket *so2)
3765 {
3766 
3767 	return EOPNOTSUPP;
3768 }
3769 
3770 int
3771 pru_control_notsupp(struct socket *so, u_long cmd, caddr_t data,
3772     struct ifnet *ifp, struct thread *td)
3773 {
3774 
3775 	return EOPNOTSUPP;
3776 }
3777 
3778 int
3779 pru_disconnect_notsupp(struct socket *so)
3780 {
3781 
3782 	return EOPNOTSUPP;
3783 }
3784 
3785 int
3786 pru_listen_notsupp(struct socket *so, int backlog, struct thread *td)
3787 {
3788 
3789 	return EOPNOTSUPP;
3790 }
3791 
3792 int
3793 pru_peeraddr_notsupp(struct socket *so, struct sockaddr **nam)
3794 {
3795 
3796 	return EOPNOTSUPP;
3797 }
3798 
3799 int
3800 pru_rcvd_notsupp(struct socket *so, int flags)
3801 {
3802 
3803 	return EOPNOTSUPP;
3804 }
3805 
3806 int
3807 pru_rcvoob_notsupp(struct socket *so, struct mbuf *m, int flags)
3808 {
3809 
3810 	return EOPNOTSUPP;
3811 }
3812 
3813 int
3814 pru_send_notsupp(struct socket *so, int flags, struct mbuf *m,
3815     struct sockaddr *addr, struct mbuf *control, struct thread *td)
3816 {
3817 
3818 	if (control != NULL)
3819 		m_freem(control);
3820 	if ((flags & PRUS_NOTREADY) == 0)
3821 		m_freem(m);
3822 	return (EOPNOTSUPP);
3823 }
3824 
3825 int
3826 pru_ready_notsupp(struct socket *so, struct mbuf *m, int count)
3827 {
3828 
3829 	return (EOPNOTSUPP);
3830 }
3831 
3832 /*
3833  * This isn't really a ``null'' operation, but it's the default one and
3834  * doesn't do anything destructive.
3835  */
3836 int
3837 pru_sense_null(struct socket *so, struct stat *sb)
3838 {
3839 
3840 	sb->st_blksize = so->so_snd.sb_hiwat;
3841 	return 0;
3842 }
3843 
3844 int
3845 pru_shutdown_notsupp(struct socket *so)
3846 {
3847 
3848 	return EOPNOTSUPP;
3849 }
3850 
3851 int
3852 pru_sockaddr_notsupp(struct socket *so, struct sockaddr **nam)
3853 {
3854 
3855 	return EOPNOTSUPP;
3856 }
3857 
3858 int
3859 pru_sosend_notsupp(struct socket *so, struct sockaddr *addr, struct uio *uio,
3860     struct mbuf *top, struct mbuf *control, int flags, struct thread *td)
3861 {
3862 
3863 	return EOPNOTSUPP;
3864 }
3865 
3866 int
3867 pru_soreceive_notsupp(struct socket *so, struct sockaddr **paddr,
3868     struct uio *uio, struct mbuf **mp0, struct mbuf **controlp, int *flagsp)
3869 {
3870 
3871 	return EOPNOTSUPP;
3872 }
3873 
3874 int
3875 pru_sopoll_notsupp(struct socket *so, int events, struct ucred *cred,
3876     struct thread *td)
3877 {
3878 
3879 	return EOPNOTSUPP;
3880 }
3881 
3882 static void
3883 filt_sordetach(struct knote *kn)
3884 {
3885 	struct socket *so = kn->kn_fp->f_data;
3886 
3887 	so_rdknl_lock(so);
3888 	knlist_remove(&so->so_rdsel.si_note, kn, 1);
3889 	if (!SOLISTENING(so) && knlist_empty(&so->so_rdsel.si_note))
3890 		so->so_rcv.sb_flags &= ~SB_KNOTE;
3891 	so_rdknl_unlock(so);
3892 }
3893 
3894 /*ARGSUSED*/
3895 static int
3896 filt_soread(struct knote *kn, long hint)
3897 {
3898 	struct socket *so;
3899 
3900 	so = kn->kn_fp->f_data;
3901 
3902 	if (SOLISTENING(so)) {
3903 		SOCK_LOCK_ASSERT(so);
3904 		kn->kn_data = so->sol_qlen;
3905 		if (so->so_error) {
3906 			kn->kn_flags |= EV_EOF;
3907 			kn->kn_fflags = so->so_error;
3908 			return (1);
3909 		}
3910 		return (!TAILQ_EMPTY(&so->sol_comp));
3911 	}
3912 
3913 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
3914 
3915 	kn->kn_data = sbavail(&so->so_rcv) - so->so_rcv.sb_ctl;
3916 	if (so->so_rcv.sb_state & SBS_CANTRCVMORE) {
3917 		kn->kn_flags |= EV_EOF;
3918 		kn->kn_fflags = so->so_error;
3919 		return (1);
3920 	} else if (so->so_error || so->so_rerror)
3921 		return (1);
3922 
3923 	if (kn->kn_sfflags & NOTE_LOWAT) {
3924 		if (kn->kn_data >= kn->kn_sdata)
3925 			return (1);
3926 	} else if (sbavail(&so->so_rcv) >= so->so_rcv.sb_lowat)
3927 		return (1);
3928 
3929 	/* This hook returning non-zero indicates an event, not error */
3930 	return (hhook_run_socket(so, NULL, HHOOK_FILT_SOREAD));
3931 }
3932 
3933 static void
3934 filt_sowdetach(struct knote *kn)
3935 {
3936 	struct socket *so = kn->kn_fp->f_data;
3937 
3938 	so_wrknl_lock(so);
3939 	knlist_remove(&so->so_wrsel.si_note, kn, 1);
3940 	if (!SOLISTENING(so) && knlist_empty(&so->so_wrsel.si_note))
3941 		so->so_snd.sb_flags &= ~SB_KNOTE;
3942 	so_wrknl_unlock(so);
3943 }
3944 
3945 /*ARGSUSED*/
3946 static int
3947 filt_sowrite(struct knote *kn, long hint)
3948 {
3949 	struct socket *so;
3950 
3951 	so = kn->kn_fp->f_data;
3952 
3953 	if (SOLISTENING(so))
3954 		return (0);
3955 
3956 	SOCKBUF_LOCK_ASSERT(&so->so_snd);
3957 	kn->kn_data = sbspace(&so->so_snd);
3958 
3959 	hhook_run_socket(so, kn, HHOOK_FILT_SOWRITE);
3960 
3961 	if (so->so_snd.sb_state & SBS_CANTSENDMORE) {
3962 		kn->kn_flags |= EV_EOF;
3963 		kn->kn_fflags = so->so_error;
3964 		return (1);
3965 	} else if (so->so_error)	/* temporary udp error */
3966 		return (1);
3967 	else if (((so->so_state & SS_ISCONNECTED) == 0) &&
3968 	    (so->so_proto->pr_flags & PR_CONNREQUIRED))
3969 		return (0);
3970 	else if (kn->kn_sfflags & NOTE_LOWAT)
3971 		return (kn->kn_data >= kn->kn_sdata);
3972 	else
3973 		return (kn->kn_data >= so->so_snd.sb_lowat);
3974 }
3975 
3976 static int
3977 filt_soempty(struct knote *kn, long hint)
3978 {
3979 	struct socket *so;
3980 
3981 	so = kn->kn_fp->f_data;
3982 
3983 	if (SOLISTENING(so))
3984 		return (1);
3985 
3986 	SOCKBUF_LOCK_ASSERT(&so->so_snd);
3987 	kn->kn_data = sbused(&so->so_snd);
3988 
3989 	if (kn->kn_data == 0)
3990 		return (1);
3991 	else
3992 		return (0);
3993 }
3994 
3995 int
3996 socheckuid(struct socket *so, uid_t uid)
3997 {
3998 
3999 	if (so == NULL)
4000 		return (EPERM);
4001 	if (so->so_cred->cr_uid != uid)
4002 		return (EPERM);
4003 	return (0);
4004 }
4005 
4006 /*
4007  * These functions are used by protocols to notify the socket layer (and its
4008  * consumers) of state changes in the sockets driven by protocol-side events.
4009  */
4010 
4011 /*
4012  * Procedures to manipulate state flags of socket and do appropriate wakeups.
4013  *
4014  * Normal sequence from the active (originating) side is that
4015  * soisconnecting() is called during processing of connect() call, resulting
4016  * in an eventual call to soisconnected() if/when the connection is
4017  * established.  When the connection is torn down soisdisconnecting() is
4018  * called during processing of disconnect() call, and soisdisconnected() is
4019  * called when the connection to the peer is totally severed.  The semantics
4020  * of these routines are such that connectionless protocols can call
4021  * soisconnected() and soisdisconnected() only, bypassing the in-progress
4022  * calls when setting up a ``connection'' takes no time.
4023  *
4024  * From the passive side, a socket is created with two queues of sockets:
4025  * so_incomp for connections in progress and so_comp for connections already
4026  * made and awaiting user acceptance.  As a protocol is preparing incoming
4027  * connections, it creates a socket structure queued on so_incomp by calling
4028  * sonewconn().  When the connection is established, soisconnected() is
4029  * called, and transfers the socket structure to so_comp, making it available
4030  * to accept().
4031  *
4032  * If a socket is closed with sockets on either so_incomp or so_comp, these
4033  * sockets are dropped.
4034  *
4035  * If higher-level protocols are implemented in the kernel, the wakeups done
4036  * here will sometimes cause software-interrupt process scheduling.
4037  */
4038 void
4039 soisconnecting(struct socket *so)
4040 {
4041 
4042 	SOCK_LOCK(so);
4043 	so->so_state &= ~(SS_ISCONNECTED|SS_ISDISCONNECTING);
4044 	so->so_state |= SS_ISCONNECTING;
4045 	SOCK_UNLOCK(so);
4046 }
4047 
4048 void
4049 soisconnected(struct socket *so)
4050 {
4051 	bool last __diagused;
4052 
4053 	SOCK_LOCK(so);
4054 	so->so_state &= ~(SS_ISCONNECTING|SS_ISDISCONNECTING|SS_ISCONFIRMING);
4055 	so->so_state |= SS_ISCONNECTED;
4056 
4057 	if (so->so_qstate == SQ_INCOMP) {
4058 		struct socket *head = so->so_listen;
4059 		int ret;
4060 
4061 		KASSERT(head, ("%s: so %p on incomp of NULL", __func__, so));
4062 		/*
4063 		 * Promoting a socket from incomplete queue to complete, we
4064 		 * need to go through reverse order of locking.  We first do
4065 		 * trylock, and if that doesn't succeed, we go the hard way
4066 		 * leaving a reference and rechecking consistency after proper
4067 		 * locking.
4068 		 */
4069 		if (__predict_false(SOLISTEN_TRYLOCK(head) == 0)) {
4070 			soref(head);
4071 			SOCK_UNLOCK(so);
4072 			SOLISTEN_LOCK(head);
4073 			SOCK_LOCK(so);
4074 			if (__predict_false(head != so->so_listen)) {
4075 				/*
4076 				 * The socket went off the listen queue,
4077 				 * should be lost race to close(2) of sol.
4078 				 * The socket is about to soabort().
4079 				 */
4080 				SOCK_UNLOCK(so);
4081 				sorele_locked(head);
4082 				return;
4083 			}
4084 			last = refcount_release(&head->so_count);
4085 			KASSERT(!last, ("%s: released last reference for %p",
4086 			    __func__, head));
4087 		}
4088 again:
4089 		if ((so->so_options & SO_ACCEPTFILTER) == 0) {
4090 			TAILQ_REMOVE(&head->sol_incomp, so, so_list);
4091 			head->sol_incqlen--;
4092 			TAILQ_INSERT_TAIL(&head->sol_comp, so, so_list);
4093 			head->sol_qlen++;
4094 			so->so_qstate = SQ_COMP;
4095 			SOCK_UNLOCK(so);
4096 			solisten_wakeup(head);	/* unlocks */
4097 		} else {
4098 			SOCKBUF_LOCK(&so->so_rcv);
4099 			soupcall_set(so, SO_RCV,
4100 			    head->sol_accept_filter->accf_callback,
4101 			    head->sol_accept_filter_arg);
4102 			so->so_options &= ~SO_ACCEPTFILTER;
4103 			ret = head->sol_accept_filter->accf_callback(so,
4104 			    head->sol_accept_filter_arg, M_NOWAIT);
4105 			if (ret == SU_ISCONNECTED) {
4106 				soupcall_clear(so, SO_RCV);
4107 				SOCKBUF_UNLOCK(&so->so_rcv);
4108 				goto again;
4109 			}
4110 			SOCKBUF_UNLOCK(&so->so_rcv);
4111 			SOCK_UNLOCK(so);
4112 			SOLISTEN_UNLOCK(head);
4113 		}
4114 		return;
4115 	}
4116 	SOCK_UNLOCK(so);
4117 	wakeup(&so->so_timeo);
4118 	sorwakeup(so);
4119 	sowwakeup(so);
4120 }
4121 
4122 void
4123 soisdisconnecting(struct socket *so)
4124 {
4125 
4126 	SOCK_LOCK(so);
4127 	so->so_state &= ~SS_ISCONNECTING;
4128 	so->so_state |= SS_ISDISCONNECTING;
4129 
4130 	if (!SOLISTENING(so)) {
4131 		SOCKBUF_LOCK(&so->so_rcv);
4132 		socantrcvmore_locked(so);
4133 		SOCKBUF_LOCK(&so->so_snd);
4134 		socantsendmore_locked(so);
4135 	}
4136 	SOCK_UNLOCK(so);
4137 	wakeup(&so->so_timeo);
4138 }
4139 
4140 void
4141 soisdisconnected(struct socket *so)
4142 {
4143 
4144 	SOCK_LOCK(so);
4145 
4146 	/*
4147 	 * There is at least one reader of so_state that does not
4148 	 * acquire socket lock, namely soreceive_generic().  Ensure
4149 	 * that it never sees all flags that track connection status
4150 	 * cleared, by ordering the update with a barrier semantic of
4151 	 * our release thread fence.
4152 	 */
4153 	so->so_state |= SS_ISDISCONNECTED;
4154 	atomic_thread_fence_rel();
4155 	so->so_state &= ~(SS_ISCONNECTING|SS_ISCONNECTED|SS_ISDISCONNECTING);
4156 
4157 	if (!SOLISTENING(so)) {
4158 		SOCK_UNLOCK(so);
4159 		SOCKBUF_LOCK(&so->so_rcv);
4160 		socantrcvmore_locked(so);
4161 		SOCKBUF_LOCK(&so->so_snd);
4162 		sbdrop_locked(&so->so_snd, sbused(&so->so_snd));
4163 		socantsendmore_locked(so);
4164 	} else
4165 		SOCK_UNLOCK(so);
4166 	wakeup(&so->so_timeo);
4167 }
4168 
4169 int
4170 soiolock(struct socket *so, struct sx *sx, int flags)
4171 {
4172 	int error;
4173 
4174 	KASSERT((flags & SBL_VALID) == flags,
4175 	    ("soiolock: invalid flags %#x", flags));
4176 
4177 	if ((flags & SBL_WAIT) != 0) {
4178 		if ((flags & SBL_NOINTR) != 0) {
4179 			sx_xlock(sx);
4180 		} else {
4181 			error = sx_xlock_sig(sx);
4182 			if (error != 0)
4183 				return (error);
4184 		}
4185 	} else if (!sx_try_xlock(sx)) {
4186 		return (EWOULDBLOCK);
4187 	}
4188 
4189 	if (__predict_false(SOLISTENING(so))) {
4190 		sx_xunlock(sx);
4191 		return (ENOTCONN);
4192 	}
4193 	return (0);
4194 }
4195 
4196 void
4197 soiounlock(struct sx *sx)
4198 {
4199 	sx_xunlock(sx);
4200 }
4201 
4202 /*
4203  * Make a copy of a sockaddr in a malloced buffer of type M_SONAME.
4204  */
4205 struct sockaddr *
4206 sodupsockaddr(const struct sockaddr *sa, int mflags)
4207 {
4208 	struct sockaddr *sa2;
4209 
4210 	sa2 = malloc(sa->sa_len, M_SONAME, mflags);
4211 	if (sa2)
4212 		bcopy(sa, sa2, sa->sa_len);
4213 	return sa2;
4214 }
4215 
4216 /*
4217  * Register per-socket destructor.
4218  */
4219 void
4220 sodtor_set(struct socket *so, so_dtor_t *func)
4221 {
4222 
4223 	SOCK_LOCK_ASSERT(so);
4224 	so->so_dtor = func;
4225 }
4226 
4227 /*
4228  * Register per-socket buffer upcalls.
4229  */
4230 void
4231 soupcall_set(struct socket *so, int which, so_upcall_t func, void *arg)
4232 {
4233 	struct sockbuf *sb;
4234 
4235 	KASSERT(!SOLISTENING(so), ("%s: so %p listening", __func__, so));
4236 
4237 	switch (which) {
4238 	case SO_RCV:
4239 		sb = &so->so_rcv;
4240 		break;
4241 	case SO_SND:
4242 		sb = &so->so_snd;
4243 		break;
4244 	default:
4245 		panic("soupcall_set: bad which");
4246 	}
4247 	SOCKBUF_LOCK_ASSERT(sb);
4248 	sb->sb_upcall = func;
4249 	sb->sb_upcallarg = arg;
4250 	sb->sb_flags |= SB_UPCALL;
4251 }
4252 
4253 void
4254 soupcall_clear(struct socket *so, int which)
4255 {
4256 	struct sockbuf *sb;
4257 
4258 	KASSERT(!SOLISTENING(so), ("%s: so %p listening", __func__, so));
4259 
4260 	switch (which) {
4261 	case SO_RCV:
4262 		sb = &so->so_rcv;
4263 		break;
4264 	case SO_SND:
4265 		sb = &so->so_snd;
4266 		break;
4267 	default:
4268 		panic("soupcall_clear: bad which");
4269 	}
4270 	SOCKBUF_LOCK_ASSERT(sb);
4271 	KASSERT(sb->sb_upcall != NULL,
4272 	    ("%s: so %p no upcall to clear", __func__, so));
4273 	sb->sb_upcall = NULL;
4274 	sb->sb_upcallarg = NULL;
4275 	sb->sb_flags &= ~SB_UPCALL;
4276 }
4277 
4278 void
4279 solisten_upcall_set(struct socket *so, so_upcall_t func, void *arg)
4280 {
4281 
4282 	SOLISTEN_LOCK_ASSERT(so);
4283 	so->sol_upcall = func;
4284 	so->sol_upcallarg = arg;
4285 }
4286 
4287 static void
4288 so_rdknl_lock(void *arg)
4289 {
4290 	struct socket *so = arg;
4291 
4292 	if (SOLISTENING(so))
4293 		SOCK_LOCK(so);
4294 	else
4295 		SOCKBUF_LOCK(&so->so_rcv);
4296 }
4297 
4298 static void
4299 so_rdknl_unlock(void *arg)
4300 {
4301 	struct socket *so = arg;
4302 
4303 	if (SOLISTENING(so))
4304 		SOCK_UNLOCK(so);
4305 	else
4306 		SOCKBUF_UNLOCK(&so->so_rcv);
4307 }
4308 
4309 static void
4310 so_rdknl_assert_lock(void *arg, int what)
4311 {
4312 	struct socket *so = arg;
4313 
4314 	if (what == LA_LOCKED) {
4315 		if (SOLISTENING(so))
4316 			SOCK_LOCK_ASSERT(so);
4317 		else
4318 			SOCKBUF_LOCK_ASSERT(&so->so_rcv);
4319 	} else {
4320 		if (SOLISTENING(so))
4321 			SOCK_UNLOCK_ASSERT(so);
4322 		else
4323 			SOCKBUF_UNLOCK_ASSERT(&so->so_rcv);
4324 	}
4325 }
4326 
4327 static void
4328 so_wrknl_lock(void *arg)
4329 {
4330 	struct socket *so = arg;
4331 
4332 	if (SOLISTENING(so))
4333 		SOCK_LOCK(so);
4334 	else
4335 		SOCKBUF_LOCK(&so->so_snd);
4336 }
4337 
4338 static void
4339 so_wrknl_unlock(void *arg)
4340 {
4341 	struct socket *so = arg;
4342 
4343 	if (SOLISTENING(so))
4344 		SOCK_UNLOCK(so);
4345 	else
4346 		SOCKBUF_UNLOCK(&so->so_snd);
4347 }
4348 
4349 static void
4350 so_wrknl_assert_lock(void *arg, int what)
4351 {
4352 	struct socket *so = arg;
4353 
4354 	if (what == LA_LOCKED) {
4355 		if (SOLISTENING(so))
4356 			SOCK_LOCK_ASSERT(so);
4357 		else
4358 			SOCKBUF_LOCK_ASSERT(&so->so_snd);
4359 	} else {
4360 		if (SOLISTENING(so))
4361 			SOCK_UNLOCK_ASSERT(so);
4362 		else
4363 			SOCKBUF_UNLOCK_ASSERT(&so->so_snd);
4364 	}
4365 }
4366 
4367 /*
4368  * Create an external-format (``xsocket'') structure using the information in
4369  * the kernel-format socket structure pointed to by so.  This is done to
4370  * reduce the spew of irrelevant information over this interface, to isolate
4371  * user code from changes in the kernel structure, and potentially to provide
4372  * information-hiding if we decide that some of this information should be
4373  * hidden from users.
4374  */
4375 void
4376 sotoxsocket(struct socket *so, struct xsocket *xso)
4377 {
4378 
4379 	bzero(xso, sizeof(*xso));
4380 	xso->xso_len = sizeof *xso;
4381 	xso->xso_so = (uintptr_t)so;
4382 	xso->so_type = so->so_type;
4383 	xso->so_options = so->so_options;
4384 	xso->so_linger = so->so_linger;
4385 	xso->so_state = so->so_state;
4386 	xso->so_pcb = (uintptr_t)so->so_pcb;
4387 	xso->xso_protocol = so->so_proto->pr_protocol;
4388 	xso->xso_family = so->so_proto->pr_domain->dom_family;
4389 	xso->so_timeo = so->so_timeo;
4390 	xso->so_error = so->so_error;
4391 	xso->so_uid = so->so_cred->cr_uid;
4392 	xso->so_pgid = so->so_sigio ? so->so_sigio->sio_pgid : 0;
4393 	if (SOLISTENING(so)) {
4394 		xso->so_qlen = so->sol_qlen;
4395 		xso->so_incqlen = so->sol_incqlen;
4396 		xso->so_qlimit = so->sol_qlimit;
4397 		xso->so_oobmark = 0;
4398 	} else {
4399 		xso->so_state |= so->so_qstate;
4400 		xso->so_qlen = xso->so_incqlen = xso->so_qlimit = 0;
4401 		xso->so_oobmark = so->so_oobmark;
4402 		sbtoxsockbuf(&so->so_snd, &xso->so_snd);
4403 		sbtoxsockbuf(&so->so_rcv, &xso->so_rcv);
4404 	}
4405 }
4406 
4407 struct sockbuf *
4408 so_sockbuf_rcv(struct socket *so)
4409 {
4410 
4411 	return (&so->so_rcv);
4412 }
4413 
4414 struct sockbuf *
4415 so_sockbuf_snd(struct socket *so)
4416 {
4417 
4418 	return (&so->so_snd);
4419 }
4420 
4421 int
4422 so_state_get(const struct socket *so)
4423 {
4424 
4425 	return (so->so_state);
4426 }
4427 
4428 void
4429 so_state_set(struct socket *so, int val)
4430 {
4431 
4432 	so->so_state = val;
4433 }
4434 
4435 int
4436 so_options_get(const struct socket *so)
4437 {
4438 
4439 	return (so->so_options);
4440 }
4441 
4442 void
4443 so_options_set(struct socket *so, int val)
4444 {
4445 
4446 	so->so_options = val;
4447 }
4448 
4449 int
4450 so_error_get(const struct socket *so)
4451 {
4452 
4453 	return (so->so_error);
4454 }
4455 
4456 void
4457 so_error_set(struct socket *so, int val)
4458 {
4459 
4460 	so->so_error = val;
4461 }
4462 
4463 int
4464 so_linger_get(const struct socket *so)
4465 {
4466 
4467 	return (so->so_linger);
4468 }
4469 
4470 void
4471 so_linger_set(struct socket *so, int val)
4472 {
4473 
4474 	KASSERT(val >= 0 && val <= USHRT_MAX && val <= (INT_MAX / hz),
4475 	    ("%s: val %d out of range", __func__, val));
4476 
4477 	so->so_linger = val;
4478 }
4479 
4480 struct protosw *
4481 so_protosw_get(const struct socket *so)
4482 {
4483 
4484 	return (so->so_proto);
4485 }
4486 
4487 void
4488 so_protosw_set(struct socket *so, struct protosw *val)
4489 {
4490 
4491 	so->so_proto = val;
4492 }
4493 
4494 void
4495 so_sorwakeup(struct socket *so)
4496 {
4497 
4498 	sorwakeup(so);
4499 }
4500 
4501 void
4502 so_sowwakeup(struct socket *so)
4503 {
4504 
4505 	sowwakeup(so);
4506 }
4507 
4508 void
4509 so_sorwakeup_locked(struct socket *so)
4510 {
4511 
4512 	sorwakeup_locked(so);
4513 }
4514 
4515 void
4516 so_sowwakeup_locked(struct socket *so)
4517 {
4518 
4519 	sowwakeup_locked(so);
4520 }
4521 
4522 void
4523 so_lock(struct socket *so)
4524 {
4525 
4526 	SOCK_LOCK(so);
4527 }
4528 
4529 void
4530 so_unlock(struct socket *so)
4531 {
4532 
4533 	SOCK_UNLOCK(so);
4534 }
4535