xref: /freebsd/sys/kern/uipc_socket.c (revision 41ce62251c1ed0003fc13b8735de5f9eff4c5c03)
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/fcntl.h>
116 #include <sys/limits.h>
117 #include <sys/lock.h>
118 #include <sys/mac.h>
119 #include <sys/malloc.h>
120 #include <sys/mbuf.h>
121 #include <sys/mutex.h>
122 #include <sys/domain.h>
123 #include <sys/file.h>			/* for struct knote */
124 #include <sys/hhook.h>
125 #include <sys/kernel.h>
126 #include <sys/khelp.h>
127 #include <sys/ktls.h>
128 #include <sys/event.h>
129 #include <sys/eventhandler.h>
130 #include <sys/poll.h>
131 #include <sys/proc.h>
132 #include <sys/protosw.h>
133 #include <sys/sbuf.h>
134 #include <sys/socket.h>
135 #include <sys/socketvar.h>
136 #include <sys/resourcevar.h>
137 #include <net/route.h>
138 #include <sys/signalvar.h>
139 #include <sys/stat.h>
140 #include <sys/sx.h>
141 #include <sys/sysctl.h>
142 #include <sys/taskqueue.h>
143 #include <sys/uio.h>
144 #include <sys/un.h>
145 #include <sys/unpcb.h>
146 #include <sys/jail.h>
147 #include <sys/syslog.h>
148 #include <netinet/in.h>
149 #include <netinet/in_pcb.h>
150 #include <netinet/tcp.h>
151 
152 #include <net/vnet.h>
153 
154 #include <security/mac/mac_framework.h>
155 
156 #include <vm/uma.h>
157 
158 #ifdef COMPAT_FREEBSD32
159 #include <sys/mount.h>
160 #include <sys/sysent.h>
161 #include <compat/freebsd32/freebsd32.h>
162 #endif
163 
164 static int	soreceive_rcvoob(struct socket *so, struct uio *uio,
165 		    int flags);
166 static void	so_rdknl_lock(void *);
167 static void	so_rdknl_unlock(void *);
168 static void	so_rdknl_assert_lock(void *, int);
169 static void	so_wrknl_lock(void *);
170 static void	so_wrknl_unlock(void *);
171 static void	so_wrknl_assert_lock(void *, int);
172 
173 static void	filt_sordetach(struct knote *kn);
174 static int	filt_soread(struct knote *kn, long hint);
175 static void	filt_sowdetach(struct knote *kn);
176 static int	filt_sowrite(struct knote *kn, long hint);
177 static int	filt_soempty(struct knote *kn, long hint);
178 static int inline hhook_run_socket(struct socket *so, void *hctx, int32_t h_id);
179 fo_kqfilter_t	soo_kqfilter;
180 
181 static struct filterops soread_filtops = {
182 	.f_isfd = 1,
183 	.f_detach = filt_sordetach,
184 	.f_event = filt_soread,
185 };
186 static struct filterops sowrite_filtops = {
187 	.f_isfd = 1,
188 	.f_detach = filt_sowdetach,
189 	.f_event = filt_sowrite,
190 };
191 static struct filterops soempty_filtops = {
192 	.f_isfd = 1,
193 	.f_detach = filt_sowdetach,
194 	.f_event = filt_soempty,
195 };
196 
197 so_gen_t	so_gencnt;	/* generation count for sockets */
198 
199 MALLOC_DEFINE(M_SONAME, "soname", "socket name");
200 MALLOC_DEFINE(M_PCB, "pcb", "protocol control block");
201 
202 #define	VNET_SO_ASSERT(so)						\
203 	VNET_ASSERT(curvnet != NULL,					\
204 	    ("%s:%d curvnet is NULL, so=%p", __func__, __LINE__, (so)));
205 
206 VNET_DEFINE(struct hhook_head *, socket_hhh[HHOOK_SOCKET_LAST + 1]);
207 #define	V_socket_hhh		VNET(socket_hhh)
208 
209 /*
210  * Limit on the number of connections in the listen queue waiting
211  * for accept(2).
212  * NB: The original sysctl somaxconn is still available but hidden
213  * to prevent confusion about the actual purpose of this number.
214  */
215 static u_int somaxconn = SOMAXCONN;
216 
217 static int
218 sysctl_somaxconn(SYSCTL_HANDLER_ARGS)
219 {
220 	int error;
221 	int val;
222 
223 	val = somaxconn;
224 	error = sysctl_handle_int(oidp, &val, 0, req);
225 	if (error || !req->newptr )
226 		return (error);
227 
228 	/*
229 	 * The purpose of the UINT_MAX / 3 limit, is so that the formula
230 	 *   3 * so_qlimit / 2
231 	 * below, will not overflow.
232          */
233 
234 	if (val < 1 || val > UINT_MAX / 3)
235 		return (EINVAL);
236 
237 	somaxconn = val;
238 	return (0);
239 }
240 SYSCTL_PROC(_kern_ipc, OID_AUTO, soacceptqueue,
241     CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 0, sizeof(int),
242     sysctl_somaxconn, "I",
243     "Maximum listen socket pending connection accept queue size");
244 SYSCTL_PROC(_kern_ipc, KIPC_SOMAXCONN, somaxconn,
245     CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_SKIP | CTLFLAG_NEEDGIANT, 0,
246     sizeof(int), sysctl_somaxconn, "I",
247     "Maximum listen socket pending connection accept queue size (compat)");
248 
249 static int numopensockets;
250 SYSCTL_INT(_kern_ipc, OID_AUTO, numopensockets, CTLFLAG_RD,
251     &numopensockets, 0, "Number of open sockets");
252 
253 /*
254  * accept_mtx locks down per-socket fields relating to accept queues.  See
255  * socketvar.h for an annotation of the protected fields of struct socket.
256  */
257 struct mtx accept_mtx;
258 MTX_SYSINIT(accept_mtx, &accept_mtx, "accept", MTX_DEF);
259 
260 /*
261  * so_global_mtx protects so_gencnt, numopensockets, and the per-socket
262  * so_gencnt field.
263  */
264 static struct mtx so_global_mtx;
265 MTX_SYSINIT(so_global_mtx, &so_global_mtx, "so_glabel", MTX_DEF);
266 
267 /*
268  * General IPC sysctl name space, used by sockets and a variety of other IPC
269  * types.
270  */
271 SYSCTL_NODE(_kern, KERN_IPC, ipc, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
272     "IPC");
273 
274 /*
275  * Initialize the socket subsystem and set up the socket
276  * memory allocator.
277  */
278 static uma_zone_t socket_zone;
279 int	maxsockets;
280 
281 static void
282 socket_zone_change(void *tag)
283 {
284 
285 	maxsockets = uma_zone_set_max(socket_zone, maxsockets);
286 }
287 
288 static void
289 socket_hhook_register(int subtype)
290 {
291 
292 	if (hhook_head_register(HHOOK_TYPE_SOCKET, subtype,
293 	    &V_socket_hhh[subtype],
294 	    HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0)
295 		printf("%s: WARNING: unable to register hook\n", __func__);
296 }
297 
298 static void
299 socket_hhook_deregister(int subtype)
300 {
301 
302 	if (hhook_head_deregister(V_socket_hhh[subtype]) != 0)
303 		printf("%s: WARNING: unable to deregister hook\n", __func__);
304 }
305 
306 static void
307 socket_init(void *tag)
308 {
309 
310 	socket_zone = uma_zcreate("socket", sizeof(struct socket), NULL, NULL,
311 	    NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE);
312 	maxsockets = uma_zone_set_max(socket_zone, maxsockets);
313 	uma_zone_set_warning(socket_zone, "kern.ipc.maxsockets limit reached");
314 	EVENTHANDLER_REGISTER(maxsockets_change, socket_zone_change, NULL,
315 	    EVENTHANDLER_PRI_FIRST);
316 }
317 SYSINIT(socket, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY, socket_init, NULL);
318 
319 static void
320 socket_vnet_init(const void *unused __unused)
321 {
322 	int i;
323 
324 	/* We expect a contiguous range */
325 	for (i = 0; i <= HHOOK_SOCKET_LAST; i++)
326 		socket_hhook_register(i);
327 }
328 VNET_SYSINIT(socket_vnet_init, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY,
329     socket_vnet_init, NULL);
330 
331 static void
332 socket_vnet_uninit(const void *unused __unused)
333 {
334 	int i;
335 
336 	for (i = 0; i <= HHOOK_SOCKET_LAST; i++)
337 		socket_hhook_deregister(i);
338 }
339 VNET_SYSUNINIT(socket_vnet_uninit, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY,
340     socket_vnet_uninit, NULL);
341 
342 /*
343  * Initialise maxsockets.  This SYSINIT must be run after
344  * tunable_mbinit().
345  */
346 static void
347 init_maxsockets(void *ignored)
348 {
349 
350 	TUNABLE_INT_FETCH("kern.ipc.maxsockets", &maxsockets);
351 	maxsockets = imax(maxsockets, maxfiles);
352 }
353 SYSINIT(param, SI_SUB_TUNABLES, SI_ORDER_ANY, init_maxsockets, NULL);
354 
355 /*
356  * Sysctl to get and set the maximum global sockets limit.  Notify protocols
357  * of the change so that they can update their dependent limits as required.
358  */
359 static int
360 sysctl_maxsockets(SYSCTL_HANDLER_ARGS)
361 {
362 	int error, newmaxsockets;
363 
364 	newmaxsockets = maxsockets;
365 	error = sysctl_handle_int(oidp, &newmaxsockets, 0, req);
366 	if (error == 0 && req->newptr) {
367 		if (newmaxsockets > maxsockets &&
368 		    newmaxsockets <= maxfiles) {
369 			maxsockets = newmaxsockets;
370 			EVENTHANDLER_INVOKE(maxsockets_change);
371 		} else
372 			error = EINVAL;
373 	}
374 	return (error);
375 }
376 SYSCTL_PROC(_kern_ipc, OID_AUTO, maxsockets,
377     CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, &maxsockets, 0,
378     sysctl_maxsockets, "IU",
379     "Maximum number of sockets available");
380 
381 /*
382  * Socket operation routines.  These routines are called by the routines in
383  * sys_socket.c or from a system process, and implement the semantics of
384  * socket operations by switching out to the protocol specific routines.
385  */
386 
387 /*
388  * Get a socket structure from our zone, and initialize it.  Note that it
389  * would probably be better to allocate socket and PCB at the same time, but
390  * I'm not convinced that all the protocols can be easily modified to do
391  * this.
392  *
393  * soalloc() returns a socket with a ref count of 0.
394  */
395 static struct socket *
396 soalloc(struct vnet *vnet)
397 {
398 	struct socket *so;
399 
400 	so = uma_zalloc(socket_zone, M_NOWAIT | M_ZERO);
401 	if (so == NULL)
402 		return (NULL);
403 #ifdef MAC
404 	if (mac_socket_init(so, M_NOWAIT) != 0) {
405 		uma_zfree(socket_zone, so);
406 		return (NULL);
407 	}
408 #endif
409 	if (khelp_init_osd(HELPER_CLASS_SOCKET, &so->osd)) {
410 		uma_zfree(socket_zone, so);
411 		return (NULL);
412 	}
413 
414 	/*
415 	 * The socket locking protocol allows to lock 2 sockets at a time,
416 	 * however, the first one must be a listening socket.  WITNESS lacks
417 	 * a feature to change class of an existing lock, so we use DUPOK.
418 	 */
419 	mtx_init(&so->so_lock, "socket", NULL, MTX_DEF | MTX_DUPOK);
420 	SOCKBUF_LOCK_INIT(&so->so_snd, "so_snd");
421 	SOCKBUF_LOCK_INIT(&so->so_rcv, "so_rcv");
422 	so->so_rcv.sb_sel = &so->so_rdsel;
423 	so->so_snd.sb_sel = &so->so_wrsel;
424 	sx_init(&so->so_snd.sb_sx, "so_snd_sx");
425 	sx_init(&so->so_rcv.sb_sx, "so_rcv_sx");
426 	TAILQ_INIT(&so->so_snd.sb_aiojobq);
427 	TAILQ_INIT(&so->so_rcv.sb_aiojobq);
428 	TASK_INIT(&so->so_snd.sb_aiotask, 0, soaio_snd, so);
429 	TASK_INIT(&so->so_rcv.sb_aiotask, 0, soaio_rcv, so);
430 #ifdef VIMAGE
431 	VNET_ASSERT(vnet != NULL, ("%s:%d vnet is NULL, so=%p",
432 	    __func__, __LINE__, so));
433 	so->so_vnet = vnet;
434 #endif
435 	/* We shouldn't need the so_global_mtx */
436 	if (hhook_run_socket(so, NULL, HHOOK_SOCKET_CREATE)) {
437 		/* Do we need more comprehensive error returns? */
438 		uma_zfree(socket_zone, so);
439 		return (NULL);
440 	}
441 	mtx_lock(&so_global_mtx);
442 	so->so_gencnt = ++so_gencnt;
443 	++numopensockets;
444 #ifdef VIMAGE
445 	vnet->vnet_sockcnt++;
446 #endif
447 	mtx_unlock(&so_global_mtx);
448 
449 	return (so);
450 }
451 
452 /*
453  * Free the storage associated with a socket at the socket layer, tear down
454  * locks, labels, etc.  All protocol state is assumed already to have been
455  * torn down (and possibly never set up) by the caller.
456  */
457 static void
458 sodealloc(struct socket *so)
459 {
460 
461 	KASSERT(so->so_count == 0, ("sodealloc(): so_count %d", so->so_count));
462 	KASSERT(so->so_pcb == NULL, ("sodealloc(): so_pcb != NULL"));
463 
464 	mtx_lock(&so_global_mtx);
465 	so->so_gencnt = ++so_gencnt;
466 	--numopensockets;	/* Could be below, but faster here. */
467 #ifdef VIMAGE
468 	VNET_ASSERT(so->so_vnet != NULL, ("%s:%d so_vnet is NULL, so=%p",
469 	    __func__, __LINE__, so));
470 	so->so_vnet->vnet_sockcnt--;
471 #endif
472 	mtx_unlock(&so_global_mtx);
473 #ifdef MAC
474 	mac_socket_destroy(so);
475 #endif
476 	hhook_run_socket(so, NULL, HHOOK_SOCKET_CLOSE);
477 
478 	crfree(so->so_cred);
479 	khelp_destroy_osd(&so->osd);
480 	if (SOLISTENING(so)) {
481 		if (so->sol_accept_filter != NULL)
482 			accept_filt_setopt(so, NULL);
483 	} else {
484 		if (so->so_rcv.sb_hiwat)
485 			(void)chgsbsize(so->so_cred->cr_uidinfo,
486 			    &so->so_rcv.sb_hiwat, 0, RLIM_INFINITY);
487 		if (so->so_snd.sb_hiwat)
488 			(void)chgsbsize(so->so_cred->cr_uidinfo,
489 			    &so->so_snd.sb_hiwat, 0, RLIM_INFINITY);
490 		sx_destroy(&so->so_snd.sb_sx);
491 		sx_destroy(&so->so_rcv.sb_sx);
492 		SOCKBUF_LOCK_DESTROY(&so->so_snd);
493 		SOCKBUF_LOCK_DESTROY(&so->so_rcv);
494 	}
495 	mtx_destroy(&so->so_lock);
496 	uma_zfree(socket_zone, so);
497 }
498 
499 /*
500  * socreate returns a socket with a ref count of 1.  The socket should be
501  * closed with soclose().
502  */
503 int
504 socreate(int dom, struct socket **aso, int type, int proto,
505     struct ucred *cred, struct thread *td)
506 {
507 	struct protosw *prp;
508 	struct socket *so;
509 	int error;
510 
511 	if (proto)
512 		prp = pffindproto(dom, proto, type);
513 	else
514 		prp = pffindtype(dom, type);
515 
516 	if (prp == NULL) {
517 		/* No support for domain. */
518 		if (pffinddomain(dom) == NULL)
519 			return (EAFNOSUPPORT);
520 		/* No support for socket type. */
521 		if (proto == 0 && type != 0)
522 			return (EPROTOTYPE);
523 		return (EPROTONOSUPPORT);
524 	}
525 	if (prp->pr_usrreqs->pru_attach == NULL ||
526 	    prp->pr_usrreqs->pru_attach == pru_attach_notsupp)
527 		return (EPROTONOSUPPORT);
528 
529 	if (prison_check_af(cred, prp->pr_domain->dom_family) != 0)
530 		return (EPROTONOSUPPORT);
531 
532 	if (prp->pr_type != type)
533 		return (EPROTOTYPE);
534 	so = soalloc(CRED_TO_VNET(cred));
535 	if (so == NULL)
536 		return (ENOBUFS);
537 
538 	so->so_type = type;
539 	so->so_cred = crhold(cred);
540 	if ((prp->pr_domain->dom_family == PF_INET) ||
541 	    (prp->pr_domain->dom_family == PF_INET6) ||
542 	    (prp->pr_domain->dom_family == PF_ROUTE))
543 		so->so_fibnum = td->td_proc->p_fibnum;
544 	else
545 		so->so_fibnum = 0;
546 	so->so_proto = prp;
547 #ifdef MAC
548 	mac_socket_create(cred, so);
549 #endif
550 	knlist_init(&so->so_rdsel.si_note, so, so_rdknl_lock, so_rdknl_unlock,
551 	    so_rdknl_assert_lock);
552 	knlist_init(&so->so_wrsel.si_note, so, so_wrknl_lock, so_wrknl_unlock,
553 	    so_wrknl_assert_lock);
554 	/*
555 	 * Auto-sizing of socket buffers is managed by the protocols and
556 	 * the appropriate flags must be set in the pru_attach function.
557 	 */
558 	CURVNET_SET(so->so_vnet);
559 	error = (*prp->pr_usrreqs->pru_attach)(so, proto, td);
560 	CURVNET_RESTORE();
561 	if (error) {
562 		sodealloc(so);
563 		return (error);
564 	}
565 	soref(so);
566 	*aso = so;
567 	return (0);
568 }
569 
570 #ifdef REGRESSION
571 static int regression_sonewconn_earlytest = 1;
572 SYSCTL_INT(_regression, OID_AUTO, sonewconn_earlytest, CTLFLAG_RW,
573     &regression_sonewconn_earlytest, 0, "Perform early sonewconn limit test");
574 #endif
575 
576 static struct timeval overinterval = { 60, 0 };
577 SYSCTL_TIMEVAL_SEC(_kern_ipc, OID_AUTO, sooverinterval, CTLFLAG_RW,
578     &overinterval,
579     "Delay in seconds between warnings for listen socket overflows");
580 
581 /*
582  * When an attempt at a new connection is noted on a socket which accepts
583  * connections, sonewconn is called.  If the connection is possible (subject
584  * to space constraints, etc.) then we allocate a new structure, properly
585  * linked into the data structure of the original socket, and return this.
586  * Connstatus may be 0, or SS_ISCONFIRMING, or SS_ISCONNECTED.
587  *
588  * Note: the ref count on the socket is 0 on return.
589  */
590 struct socket *
591 sonewconn(struct socket *head, int connstatus)
592 {
593 	struct sbuf descrsb;
594 	struct socket *so;
595 	int len, overcount;
596 	u_int qlen;
597 	const char localprefix[] = "local:";
598 	char descrbuf[SUNPATHLEN + sizeof(localprefix)];
599 #if defined(INET6)
600 	char addrbuf[INET6_ADDRSTRLEN];
601 #elif defined(INET)
602 	char addrbuf[INET_ADDRSTRLEN];
603 #endif
604 	bool dolog, over;
605 
606 	SOLISTEN_LOCK(head);
607 	over = (head->sol_qlen > 3 * head->sol_qlimit / 2);
608 #ifdef REGRESSION
609 	if (regression_sonewconn_earlytest && over) {
610 #else
611 	if (over) {
612 #endif
613 		head->sol_overcount++;
614 		dolog = !!ratecheck(&head->sol_lastover, &overinterval);
615 
616 		/*
617 		 * If we're going to log, copy the overflow count and queue
618 		 * length from the listen socket before dropping the lock.
619 		 * Also, reset the overflow count.
620 		 */
621 		if (dolog) {
622 			overcount = head->sol_overcount;
623 			head->sol_overcount = 0;
624 			qlen = head->sol_qlen;
625 		}
626 		SOLISTEN_UNLOCK(head);
627 
628 		if (dolog) {
629 			/*
630 			 * Try to print something descriptive about the
631 			 * socket for the error message.
632 			 */
633 			sbuf_new(&descrsb, descrbuf, sizeof(descrbuf),
634 			    SBUF_FIXEDLEN);
635 			switch (head->so_proto->pr_domain->dom_family) {
636 #if defined(INET) || defined(INET6)
637 #ifdef INET
638 			case AF_INET:
639 #endif
640 #ifdef INET6
641 			case AF_INET6:
642 				if (head->so_proto->pr_domain->dom_family ==
643 				    AF_INET6 ||
644 				    (sotoinpcb(head)->inp_inc.inc_flags &
645 				    INC_ISIPV6)) {
646 					ip6_sprintf(addrbuf,
647 					    &sotoinpcb(head)->inp_inc.inc6_laddr);
648 					sbuf_printf(&descrsb, "[%s]", addrbuf);
649 				} else
650 #endif
651 				{
652 #ifdef INET
653 					inet_ntoa_r(
654 					    sotoinpcb(head)->inp_inc.inc_laddr,
655 					    addrbuf);
656 					sbuf_cat(&descrsb, addrbuf);
657 #endif
658 				}
659 				sbuf_printf(&descrsb, ":%hu (proto %u)",
660 				    ntohs(sotoinpcb(head)->inp_inc.inc_lport),
661 				    head->so_proto->pr_protocol);
662 				break;
663 #endif /* INET || INET6 */
664 			case AF_UNIX:
665 				sbuf_cat(&descrsb, localprefix);
666 				if (sotounpcb(head)->unp_addr != NULL)
667 					len =
668 					    sotounpcb(head)->unp_addr->sun_len -
669 					    offsetof(struct sockaddr_un,
670 					    sun_path);
671 				else
672 					len = 0;
673 				if (len > 0)
674 					sbuf_bcat(&descrsb,
675 					    sotounpcb(head)->unp_addr->sun_path,
676 					    len);
677 				else
678 					sbuf_cat(&descrsb, "(unknown)");
679 				break;
680 			}
681 
682 			/*
683 			 * If we can't print something more specific, at least
684 			 * print the domain name.
685 			 */
686 			if (sbuf_finish(&descrsb) != 0 ||
687 			    sbuf_len(&descrsb) <= 0) {
688 				sbuf_clear(&descrsb);
689 				sbuf_cat(&descrsb,
690 				    head->so_proto->pr_domain->dom_name ?:
691 				    "unknown");
692 				sbuf_finish(&descrsb);
693 			}
694 			KASSERT(sbuf_len(&descrsb) > 0,
695 			    ("%s: sbuf creation failed", __func__));
696 			log(LOG_DEBUG,
697 			    "%s: pcb %p (%s): Listen queue overflow: "
698 			    "%i already in queue awaiting acceptance "
699 			    "(%d occurrences)\n",
700 			    __func__, head->so_pcb, sbuf_data(&descrsb),
701 			    qlen, overcount);
702 			sbuf_delete(&descrsb);
703 
704 			overcount = 0;
705 		}
706 
707 		return (NULL);
708 	}
709 	SOLISTEN_UNLOCK(head);
710 	VNET_ASSERT(head->so_vnet != NULL, ("%s: so %p vnet is NULL",
711 	    __func__, head));
712 	so = soalloc(head->so_vnet);
713 	if (so == NULL) {
714 		log(LOG_DEBUG, "%s: pcb %p: New socket allocation failure: "
715 		    "limit reached or out of memory\n",
716 		    __func__, head->so_pcb);
717 		return (NULL);
718 	}
719 	so->so_listen = head;
720 	so->so_type = head->so_type;
721 	so->so_linger = head->so_linger;
722 	so->so_state = head->so_state | SS_NOFDREF;
723 	so->so_fibnum = head->so_fibnum;
724 	so->so_proto = head->so_proto;
725 	so->so_cred = crhold(head->so_cred);
726 #ifdef MAC
727 	mac_socket_newconn(head, so);
728 #endif
729 	knlist_init(&so->so_rdsel.si_note, so, so_rdknl_lock, so_rdknl_unlock,
730 	    so_rdknl_assert_lock);
731 	knlist_init(&so->so_wrsel.si_note, so, so_wrknl_lock, so_wrknl_unlock,
732 	    so_wrknl_assert_lock);
733 	VNET_SO_ASSERT(head);
734 	if (soreserve(so, head->sol_sbsnd_hiwat, head->sol_sbrcv_hiwat)) {
735 		sodealloc(so);
736 		log(LOG_DEBUG, "%s: pcb %p: soreserve() failed\n",
737 		    __func__, head->so_pcb);
738 		return (NULL);
739 	}
740 	if ((*so->so_proto->pr_usrreqs->pru_attach)(so, 0, NULL)) {
741 		sodealloc(so);
742 		log(LOG_DEBUG, "%s: pcb %p: pru_attach() failed\n",
743 		    __func__, head->so_pcb);
744 		return (NULL);
745 	}
746 	so->so_rcv.sb_lowat = head->sol_sbrcv_lowat;
747 	so->so_snd.sb_lowat = head->sol_sbsnd_lowat;
748 	so->so_rcv.sb_timeo = head->sol_sbrcv_timeo;
749 	so->so_snd.sb_timeo = head->sol_sbsnd_timeo;
750 	so->so_rcv.sb_flags |= head->sol_sbrcv_flags & SB_AUTOSIZE;
751 	so->so_snd.sb_flags |= head->sol_sbsnd_flags & SB_AUTOSIZE;
752 
753 	SOLISTEN_LOCK(head);
754 	if (head->sol_accept_filter != NULL)
755 		connstatus = 0;
756 	so->so_state |= connstatus;
757 	so->so_options = head->so_options & ~SO_ACCEPTCONN;
758 	soref(head); /* A socket on (in)complete queue refs head. */
759 	if (connstatus) {
760 		TAILQ_INSERT_TAIL(&head->sol_comp, so, so_list);
761 		so->so_qstate = SQ_COMP;
762 		head->sol_qlen++;
763 		solisten_wakeup(head);	/* unlocks */
764 	} else {
765 		/*
766 		 * Keep removing sockets from the head until there's room for
767 		 * us to insert on the tail.  In pre-locking revisions, this
768 		 * was a simple if(), but as we could be racing with other
769 		 * threads and soabort() requires dropping locks, we must
770 		 * loop waiting for the condition to be true.
771 		 */
772 		while (head->sol_incqlen > head->sol_qlimit) {
773 			struct socket *sp;
774 
775 			sp = TAILQ_FIRST(&head->sol_incomp);
776 			TAILQ_REMOVE(&head->sol_incomp, sp, so_list);
777 			head->sol_incqlen--;
778 			SOCK_LOCK(sp);
779 			sp->so_qstate = SQ_NONE;
780 			sp->so_listen = NULL;
781 			SOCK_UNLOCK(sp);
782 			sorele(head);	/* does SOLISTEN_UNLOCK, head stays */
783 			soabort(sp);
784 			SOLISTEN_LOCK(head);
785 		}
786 		TAILQ_INSERT_TAIL(&head->sol_incomp, so, so_list);
787 		so->so_qstate = SQ_INCOMP;
788 		head->sol_incqlen++;
789 		SOLISTEN_UNLOCK(head);
790 	}
791 	return (so);
792 }
793 
794 #if defined(SCTP) || defined(SCTP_SUPPORT)
795 /*
796  * Socket part of sctp_peeloff().  Detach a new socket from an
797  * association.  The new socket is returned with a reference.
798  */
799 struct socket *
800 sopeeloff(struct socket *head)
801 {
802 	struct socket *so;
803 
804 	VNET_ASSERT(head->so_vnet != NULL, ("%s:%d so_vnet is NULL, head=%p",
805 	    __func__, __LINE__, head));
806 	so = soalloc(head->so_vnet);
807 	if (so == NULL) {
808 		log(LOG_DEBUG, "%s: pcb %p: New socket allocation failure: "
809 		    "limit reached or out of memory\n",
810 		    __func__, head->so_pcb);
811 		return (NULL);
812 	}
813 	so->so_type = head->so_type;
814 	so->so_options = head->so_options;
815 	so->so_linger = head->so_linger;
816 	so->so_state = (head->so_state & SS_NBIO) | SS_ISCONNECTED;
817 	so->so_fibnum = head->so_fibnum;
818 	so->so_proto = head->so_proto;
819 	so->so_cred = crhold(head->so_cred);
820 #ifdef MAC
821 	mac_socket_newconn(head, so);
822 #endif
823 	knlist_init(&so->so_rdsel.si_note, so, so_rdknl_lock, so_rdknl_unlock,
824 	    so_rdknl_assert_lock);
825 	knlist_init(&so->so_wrsel.si_note, so, so_wrknl_lock, so_wrknl_unlock,
826 	    so_wrknl_assert_lock);
827 	VNET_SO_ASSERT(head);
828 	if (soreserve(so, head->so_snd.sb_hiwat, head->so_rcv.sb_hiwat)) {
829 		sodealloc(so);
830 		log(LOG_DEBUG, "%s: pcb %p: soreserve() failed\n",
831 		    __func__, head->so_pcb);
832 		return (NULL);
833 	}
834 	if ((*so->so_proto->pr_usrreqs->pru_attach)(so, 0, NULL)) {
835 		sodealloc(so);
836 		log(LOG_DEBUG, "%s: pcb %p: pru_attach() failed\n",
837 		    __func__, head->so_pcb);
838 		return (NULL);
839 	}
840 	so->so_rcv.sb_lowat = head->so_rcv.sb_lowat;
841 	so->so_snd.sb_lowat = head->so_snd.sb_lowat;
842 	so->so_rcv.sb_timeo = head->so_rcv.sb_timeo;
843 	so->so_snd.sb_timeo = head->so_snd.sb_timeo;
844 	so->so_rcv.sb_flags |= head->so_rcv.sb_flags & SB_AUTOSIZE;
845 	so->so_snd.sb_flags |= head->so_snd.sb_flags & SB_AUTOSIZE;
846 
847 	soref(so);
848 
849 	return (so);
850 }
851 #endif	/* SCTP */
852 
853 int
854 sobind(struct socket *so, struct sockaddr *nam, struct thread *td)
855 {
856 	int error;
857 
858 	CURVNET_SET(so->so_vnet);
859 	error = (*so->so_proto->pr_usrreqs->pru_bind)(so, nam, td);
860 	CURVNET_RESTORE();
861 	return (error);
862 }
863 
864 int
865 sobindat(int fd, struct socket *so, struct sockaddr *nam, struct thread *td)
866 {
867 	int error;
868 
869 	CURVNET_SET(so->so_vnet);
870 	error = (*so->so_proto->pr_usrreqs->pru_bindat)(fd, so, nam, td);
871 	CURVNET_RESTORE();
872 	return (error);
873 }
874 
875 /*
876  * solisten() transitions a socket from a non-listening state to a listening
877  * state, but can also be used to update the listen queue depth on an
878  * existing listen socket.  The protocol will call back into the sockets
879  * layer using solisten_proto_check() and solisten_proto() to check and set
880  * socket-layer listen state.  Call backs are used so that the protocol can
881  * acquire both protocol and socket layer locks in whatever order is required
882  * by the protocol.
883  *
884  * Protocol implementors are advised to hold the socket lock across the
885  * socket-layer test and set to avoid races at the socket layer.
886  */
887 int
888 solisten(struct socket *so, int backlog, struct thread *td)
889 {
890 	int error;
891 
892 	CURVNET_SET(so->so_vnet);
893 	error = (*so->so_proto->pr_usrreqs->pru_listen)(so, backlog, td);
894 	CURVNET_RESTORE();
895 	return (error);
896 }
897 
898 int
899 solisten_proto_check(struct socket *so)
900 {
901 
902 	SOCK_LOCK_ASSERT(so);
903 
904 	if (so->so_state & (SS_ISCONNECTED | SS_ISCONNECTING |
905 	    SS_ISDISCONNECTING))
906 		return (EINVAL);
907 	return (0);
908 }
909 
910 void
911 solisten_proto(struct socket *so, int backlog)
912 {
913 	int sbrcv_lowat, sbsnd_lowat;
914 	u_int sbrcv_hiwat, sbsnd_hiwat;
915 	short sbrcv_flags, sbsnd_flags;
916 	sbintime_t sbrcv_timeo, sbsnd_timeo;
917 
918 	SOCK_LOCK_ASSERT(so);
919 
920 	if (SOLISTENING(so))
921 		goto listening;
922 
923 	/*
924 	 * Change this socket to listening state.
925 	 */
926 	sbrcv_lowat = so->so_rcv.sb_lowat;
927 	sbsnd_lowat = so->so_snd.sb_lowat;
928 	sbrcv_hiwat = so->so_rcv.sb_hiwat;
929 	sbsnd_hiwat = so->so_snd.sb_hiwat;
930 	sbrcv_flags = so->so_rcv.sb_flags;
931 	sbsnd_flags = so->so_snd.sb_flags;
932 	sbrcv_timeo = so->so_rcv.sb_timeo;
933 	sbsnd_timeo = so->so_snd.sb_timeo;
934 
935 	sbdestroy(&so->so_snd, so);
936 	sbdestroy(&so->so_rcv, so);
937 	sx_destroy(&so->so_snd.sb_sx);
938 	sx_destroy(&so->so_rcv.sb_sx);
939 	SOCKBUF_LOCK_DESTROY(&so->so_snd);
940 	SOCKBUF_LOCK_DESTROY(&so->so_rcv);
941 
942 #ifdef INVARIANTS
943 	bzero(&so->so_rcv,
944 	    sizeof(struct socket) - offsetof(struct socket, so_rcv));
945 #endif
946 
947 	so->sol_sbrcv_lowat = sbrcv_lowat;
948 	so->sol_sbsnd_lowat = sbsnd_lowat;
949 	so->sol_sbrcv_hiwat = sbrcv_hiwat;
950 	so->sol_sbsnd_hiwat = sbsnd_hiwat;
951 	so->sol_sbrcv_flags = sbrcv_flags;
952 	so->sol_sbsnd_flags = sbsnd_flags;
953 	so->sol_sbrcv_timeo = sbrcv_timeo;
954 	so->sol_sbsnd_timeo = sbsnd_timeo;
955 
956 	so->sol_qlen = so->sol_incqlen = 0;
957 	TAILQ_INIT(&so->sol_incomp);
958 	TAILQ_INIT(&so->sol_comp);
959 
960 	so->sol_accept_filter = NULL;
961 	so->sol_accept_filter_arg = NULL;
962 	so->sol_accept_filter_str = NULL;
963 
964 	so->sol_upcall = NULL;
965 	so->sol_upcallarg = NULL;
966 
967 	so->so_options |= SO_ACCEPTCONN;
968 
969 listening:
970 	if (backlog < 0 || backlog > somaxconn)
971 		backlog = somaxconn;
972 	so->sol_qlimit = backlog;
973 }
974 
975 /*
976  * Wakeup listeners/subsystems once we have a complete connection.
977  * Enters with lock, returns unlocked.
978  */
979 void
980 solisten_wakeup(struct socket *sol)
981 {
982 
983 	if (sol->sol_upcall != NULL)
984 		(void )sol->sol_upcall(sol, sol->sol_upcallarg, M_NOWAIT);
985 	else {
986 		selwakeuppri(&sol->so_rdsel, PSOCK);
987 		KNOTE_LOCKED(&sol->so_rdsel.si_note, 0);
988 	}
989 	SOLISTEN_UNLOCK(sol);
990 	wakeup_one(&sol->sol_comp);
991 	if ((sol->so_state & SS_ASYNC) && sol->so_sigio != NULL)
992 		pgsigio(&sol->so_sigio, SIGIO, 0);
993 }
994 
995 /*
996  * Return single connection off a listening socket queue.  Main consumer of
997  * the function is kern_accept4().  Some modules, that do their own accept
998  * management also use the function.
999  *
1000  * Listening socket must be locked on entry and is returned unlocked on
1001  * return.
1002  * The flags argument is set of accept4(2) flags and ACCEPT4_INHERIT.
1003  */
1004 int
1005 solisten_dequeue(struct socket *head, struct socket **ret, int flags)
1006 {
1007 	struct socket *so;
1008 	int error;
1009 
1010 	SOLISTEN_LOCK_ASSERT(head);
1011 
1012 	while (!(head->so_state & SS_NBIO) && TAILQ_EMPTY(&head->sol_comp) &&
1013 	    head->so_error == 0) {
1014 		error = msleep(&head->sol_comp, &head->so_lock, PSOCK | PCATCH,
1015 		    "accept", 0);
1016 		if (error != 0) {
1017 			SOLISTEN_UNLOCK(head);
1018 			return (error);
1019 		}
1020 	}
1021 	if (head->so_error) {
1022 		error = head->so_error;
1023 		head->so_error = 0;
1024 	} else if ((head->so_state & SS_NBIO) && TAILQ_EMPTY(&head->sol_comp))
1025 		error = EWOULDBLOCK;
1026 	else
1027 		error = 0;
1028 	if (error) {
1029 		SOLISTEN_UNLOCK(head);
1030 		return (error);
1031 	}
1032 	so = TAILQ_FIRST(&head->sol_comp);
1033 	SOCK_LOCK(so);
1034 	KASSERT(so->so_qstate == SQ_COMP,
1035 	    ("%s: so %p not SQ_COMP", __func__, so));
1036 	soref(so);
1037 	head->sol_qlen--;
1038 	so->so_qstate = SQ_NONE;
1039 	so->so_listen = NULL;
1040 	TAILQ_REMOVE(&head->sol_comp, so, so_list);
1041 	if (flags & ACCEPT4_INHERIT)
1042 		so->so_state |= (head->so_state & SS_NBIO);
1043 	else
1044 		so->so_state |= (flags & SOCK_NONBLOCK) ? SS_NBIO : 0;
1045 	SOCK_UNLOCK(so);
1046 	sorele(head);
1047 
1048 	*ret = so;
1049 	return (0);
1050 }
1051 
1052 /*
1053  * Evaluate the reference count and named references on a socket; if no
1054  * references remain, free it.  This should be called whenever a reference is
1055  * released, such as in sorele(), but also when named reference flags are
1056  * cleared in socket or protocol code.
1057  *
1058  * sofree() will free the socket if:
1059  *
1060  * - There are no outstanding file descriptor references or related consumers
1061  *   (so_count == 0).
1062  *
1063  * - The socket has been closed by user space, if ever open (SS_NOFDREF).
1064  *
1065  * - The protocol does not have an outstanding strong reference on the socket
1066  *   (SS_PROTOREF).
1067  *
1068  * - The socket is not in a completed connection queue, so a process has been
1069  *   notified that it is present.  If it is removed, the user process may
1070  *   block in accept() despite select() saying the socket was ready.
1071  */
1072 void
1073 sofree(struct socket *so)
1074 {
1075 	struct protosw *pr = so->so_proto;
1076 
1077 	SOCK_LOCK_ASSERT(so);
1078 
1079 	if ((so->so_state & SS_NOFDREF) == 0 || so->so_count != 0 ||
1080 	    (so->so_state & SS_PROTOREF) || (so->so_qstate == SQ_COMP)) {
1081 		SOCK_UNLOCK(so);
1082 		return;
1083 	}
1084 
1085 	if (!SOLISTENING(so) && so->so_qstate == SQ_INCOMP) {
1086 		struct socket *sol;
1087 
1088 		sol = so->so_listen;
1089 		KASSERT(sol, ("%s: so %p on incomp of NULL", __func__, so));
1090 
1091 		/*
1092 		 * To solve race between close of a listening socket and
1093 		 * a socket on its incomplete queue, we need to lock both.
1094 		 * The order is first listening socket, then regular.
1095 		 * Since we don't have SS_NOFDREF neither SS_PROTOREF, this
1096 		 * function and the listening socket are the only pointers
1097 		 * to so.  To preserve so and sol, we reference both and then
1098 		 * relock.
1099 		 * After relock the socket may not move to so_comp since it
1100 		 * doesn't have PCB already, but it may be removed from
1101 		 * so_incomp. If that happens, we share responsiblity on
1102 		 * freeing the socket, but soclose() has already removed
1103 		 * it from queue.
1104 		 */
1105 		soref(sol);
1106 		soref(so);
1107 		SOCK_UNLOCK(so);
1108 		SOLISTEN_LOCK(sol);
1109 		SOCK_LOCK(so);
1110 		if (so->so_qstate == SQ_INCOMP) {
1111 			KASSERT(so->so_listen == sol,
1112 			    ("%s: so %p migrated out of sol %p",
1113 			    __func__, so, sol));
1114 			TAILQ_REMOVE(&sol->sol_incomp, so, so_list);
1115 			sol->sol_incqlen--;
1116 			/* This is guarenteed not to be the last. */
1117 			refcount_release(&sol->so_count);
1118 			so->so_qstate = SQ_NONE;
1119 			so->so_listen = NULL;
1120 		} else
1121 			KASSERT(so->so_listen == NULL,
1122 			    ("%s: so %p not on (in)comp with so_listen",
1123 			    __func__, so));
1124 		sorele(sol);
1125 		KASSERT(so->so_count == 1,
1126 		    ("%s: so %p count %u", __func__, so, so->so_count));
1127 		so->so_count = 0;
1128 	}
1129 	if (SOLISTENING(so))
1130 		so->so_error = ECONNABORTED;
1131 	SOCK_UNLOCK(so);
1132 
1133 	if (so->so_dtor != NULL)
1134 		so->so_dtor(so);
1135 
1136 	VNET_SO_ASSERT(so);
1137 	if (pr->pr_flags & PR_RIGHTS && pr->pr_domain->dom_dispose != NULL)
1138 		(*pr->pr_domain->dom_dispose)(so);
1139 	if (pr->pr_usrreqs->pru_detach != NULL)
1140 		(*pr->pr_usrreqs->pru_detach)(so);
1141 
1142 	/*
1143 	 * From this point on, we assume that no other references to this
1144 	 * socket exist anywhere else in the stack.  Therefore, no locks need
1145 	 * to be acquired or held.
1146 	 *
1147 	 * We used to do a lot of socket buffer and socket locking here, as
1148 	 * well as invoke sorflush() and perform wakeups.  The direct call to
1149 	 * dom_dispose() and sbdestroy() are an inlining of what was
1150 	 * necessary from sorflush().
1151 	 *
1152 	 * Notice that the socket buffer and kqueue state are torn down
1153 	 * before calling pru_detach.  This means that protocols shold not
1154 	 * assume they can perform socket wakeups, etc, in their detach code.
1155 	 */
1156 	if (!SOLISTENING(so)) {
1157 		sbdestroy(&so->so_snd, so);
1158 		sbdestroy(&so->so_rcv, so);
1159 	}
1160 	seldrain(&so->so_rdsel);
1161 	seldrain(&so->so_wrsel);
1162 	knlist_destroy(&so->so_rdsel.si_note);
1163 	knlist_destroy(&so->so_wrsel.si_note);
1164 	sodealloc(so);
1165 }
1166 
1167 /*
1168  * Close a socket on last file table reference removal.  Initiate disconnect
1169  * if connected.  Free socket when disconnect complete.
1170  *
1171  * This function will sorele() the socket.  Note that soclose() may be called
1172  * prior to the ref count reaching zero.  The actual socket structure will
1173  * not be freed until the ref count reaches zero.
1174  */
1175 int
1176 soclose(struct socket *so)
1177 {
1178 	struct accept_queue lqueue;
1179 	bool listening;
1180 	int error = 0;
1181 
1182 	KASSERT(!(so->so_state & SS_NOFDREF), ("soclose: SS_NOFDREF on enter"));
1183 
1184 	CURVNET_SET(so->so_vnet);
1185 	funsetown(&so->so_sigio);
1186 	if (so->so_state & SS_ISCONNECTED) {
1187 		if ((so->so_state & SS_ISDISCONNECTING) == 0) {
1188 			error = sodisconnect(so);
1189 			if (error) {
1190 				if (error == ENOTCONN)
1191 					error = 0;
1192 				goto drop;
1193 			}
1194 		}
1195 		if (so->so_options & SO_LINGER) {
1196 			if ((so->so_state & SS_ISDISCONNECTING) &&
1197 			    (so->so_state & SS_NBIO))
1198 				goto drop;
1199 			while (so->so_state & SS_ISCONNECTED) {
1200 				error = tsleep(&so->so_timeo,
1201 				    PSOCK | PCATCH, "soclos",
1202 				    so->so_linger * hz);
1203 				if (error)
1204 					break;
1205 			}
1206 		}
1207 	}
1208 
1209 drop:
1210 	if (so->so_proto->pr_usrreqs->pru_close != NULL)
1211 		(*so->so_proto->pr_usrreqs->pru_close)(so);
1212 
1213 	SOCK_LOCK(so);
1214 	if ((listening = (so->so_options & SO_ACCEPTCONN))) {
1215 		struct socket *sp;
1216 
1217 		TAILQ_INIT(&lqueue);
1218 		TAILQ_SWAP(&lqueue, &so->sol_incomp, socket, so_list);
1219 		TAILQ_CONCAT(&lqueue, &so->sol_comp, so_list);
1220 
1221 		so->sol_qlen = so->sol_incqlen = 0;
1222 
1223 		TAILQ_FOREACH(sp, &lqueue, so_list) {
1224 			SOCK_LOCK(sp);
1225 			sp->so_qstate = SQ_NONE;
1226 			sp->so_listen = NULL;
1227 			SOCK_UNLOCK(sp);
1228 			/* Guaranteed not to be the last. */
1229 			refcount_release(&so->so_count);
1230 		}
1231 	}
1232 	KASSERT((so->so_state & SS_NOFDREF) == 0, ("soclose: NOFDREF"));
1233 	so->so_state |= SS_NOFDREF;
1234 	sorele(so);
1235 	if (listening) {
1236 		struct socket *sp, *tsp;
1237 
1238 		TAILQ_FOREACH_SAFE(sp, &lqueue, so_list, tsp) {
1239 			SOCK_LOCK(sp);
1240 			if (sp->so_count == 0) {
1241 				SOCK_UNLOCK(sp);
1242 				soabort(sp);
1243 			} else
1244 				/* sp is now in sofree() */
1245 				SOCK_UNLOCK(sp);
1246 		}
1247 	}
1248 	CURVNET_RESTORE();
1249 	return (error);
1250 }
1251 
1252 /*
1253  * soabort() is used to abruptly tear down a connection, such as when a
1254  * resource limit is reached (listen queue depth exceeded), or if a listen
1255  * socket is closed while there are sockets waiting to be accepted.
1256  *
1257  * This interface is tricky, because it is called on an unreferenced socket,
1258  * and must be called only by a thread that has actually removed the socket
1259  * from the listen queue it was on, or races with other threads are risked.
1260  *
1261  * This interface will call into the protocol code, so must not be called
1262  * with any socket locks held.  Protocols do call it while holding their own
1263  * recursible protocol mutexes, but this is something that should be subject
1264  * to review in the future.
1265  */
1266 void
1267 soabort(struct socket *so)
1268 {
1269 
1270 	/*
1271 	 * In as much as is possible, assert that no references to this
1272 	 * socket are held.  This is not quite the same as asserting that the
1273 	 * current thread is responsible for arranging for no references, but
1274 	 * is as close as we can get for now.
1275 	 */
1276 	KASSERT(so->so_count == 0, ("soabort: so_count"));
1277 	KASSERT((so->so_state & SS_PROTOREF) == 0, ("soabort: SS_PROTOREF"));
1278 	KASSERT(so->so_state & SS_NOFDREF, ("soabort: !SS_NOFDREF"));
1279 	VNET_SO_ASSERT(so);
1280 
1281 	if (so->so_proto->pr_usrreqs->pru_abort != NULL)
1282 		(*so->so_proto->pr_usrreqs->pru_abort)(so);
1283 	SOCK_LOCK(so);
1284 	sofree(so);
1285 }
1286 
1287 int
1288 soaccept(struct socket *so, struct sockaddr **nam)
1289 {
1290 	int error;
1291 
1292 	SOCK_LOCK(so);
1293 	KASSERT((so->so_state & SS_NOFDREF) != 0, ("soaccept: !NOFDREF"));
1294 	so->so_state &= ~SS_NOFDREF;
1295 	SOCK_UNLOCK(so);
1296 
1297 	CURVNET_SET(so->so_vnet);
1298 	error = (*so->so_proto->pr_usrreqs->pru_accept)(so, nam);
1299 	CURVNET_RESTORE();
1300 	return (error);
1301 }
1302 
1303 int
1304 soconnect(struct socket *so, struct sockaddr *nam, struct thread *td)
1305 {
1306 
1307 	return (soconnectat(AT_FDCWD, so, nam, td));
1308 }
1309 
1310 int
1311 soconnectat(int fd, struct socket *so, struct sockaddr *nam, struct thread *td)
1312 {
1313 	int error;
1314 
1315 	if (so->so_options & SO_ACCEPTCONN)
1316 		return (EOPNOTSUPP);
1317 
1318 	CURVNET_SET(so->so_vnet);
1319 	/*
1320 	 * If protocol is connection-based, can only connect once.
1321 	 * Otherwise, if connected, try to disconnect first.  This allows
1322 	 * user to disconnect by connecting to, e.g., a null address.
1323 	 */
1324 	if (so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING) &&
1325 	    ((so->so_proto->pr_flags & PR_CONNREQUIRED) ||
1326 	    (error = sodisconnect(so)))) {
1327 		error = EISCONN;
1328 	} else {
1329 		/*
1330 		 * Prevent accumulated error from previous connection from
1331 		 * biting us.
1332 		 */
1333 		so->so_error = 0;
1334 		if (fd == AT_FDCWD) {
1335 			error = (*so->so_proto->pr_usrreqs->pru_connect)(so,
1336 			    nam, td);
1337 		} else {
1338 			error = (*so->so_proto->pr_usrreqs->pru_connectat)(fd,
1339 			    so, nam, td);
1340 		}
1341 	}
1342 	CURVNET_RESTORE();
1343 
1344 	return (error);
1345 }
1346 
1347 int
1348 soconnect2(struct socket *so1, struct socket *so2)
1349 {
1350 	int error;
1351 
1352 	CURVNET_SET(so1->so_vnet);
1353 	error = (*so1->so_proto->pr_usrreqs->pru_connect2)(so1, so2);
1354 	CURVNET_RESTORE();
1355 	return (error);
1356 }
1357 
1358 int
1359 sodisconnect(struct socket *so)
1360 {
1361 	int error;
1362 
1363 	if ((so->so_state & SS_ISCONNECTED) == 0)
1364 		return (ENOTCONN);
1365 	if (so->so_state & SS_ISDISCONNECTING)
1366 		return (EALREADY);
1367 	VNET_SO_ASSERT(so);
1368 	error = (*so->so_proto->pr_usrreqs->pru_disconnect)(so);
1369 	return (error);
1370 }
1371 
1372 #define	SBLOCKWAIT(f)	(((f) & MSG_DONTWAIT) ? 0 : SBL_WAIT)
1373 
1374 int
1375 sosend_dgram(struct socket *so, struct sockaddr *addr, struct uio *uio,
1376     struct mbuf *top, struct mbuf *control, int flags, struct thread *td)
1377 {
1378 	long space;
1379 	ssize_t resid;
1380 	int clen = 0, error, dontroute;
1381 
1382 	KASSERT(so->so_type == SOCK_DGRAM, ("sosend_dgram: !SOCK_DGRAM"));
1383 	KASSERT(so->so_proto->pr_flags & PR_ATOMIC,
1384 	    ("sosend_dgram: !PR_ATOMIC"));
1385 
1386 	if (uio != NULL)
1387 		resid = uio->uio_resid;
1388 	else
1389 		resid = top->m_pkthdr.len;
1390 	/*
1391 	 * In theory resid should be unsigned.  However, space must be
1392 	 * signed, as it might be less than 0 if we over-committed, and we
1393 	 * must use a signed comparison of space and resid.  On the other
1394 	 * hand, a negative resid causes us to loop sending 0-length
1395 	 * segments to the protocol.
1396 	 */
1397 	if (resid < 0) {
1398 		error = EINVAL;
1399 		goto out;
1400 	}
1401 
1402 	dontroute =
1403 	    (flags & MSG_DONTROUTE) && (so->so_options & SO_DONTROUTE) == 0;
1404 	if (td != NULL)
1405 		td->td_ru.ru_msgsnd++;
1406 	if (control != NULL)
1407 		clen = control->m_len;
1408 
1409 	SOCKBUF_LOCK(&so->so_snd);
1410 	if (so->so_snd.sb_state & SBS_CANTSENDMORE) {
1411 		SOCKBUF_UNLOCK(&so->so_snd);
1412 		error = EPIPE;
1413 		goto out;
1414 	}
1415 	if (so->so_error) {
1416 		error = so->so_error;
1417 		so->so_error = 0;
1418 		SOCKBUF_UNLOCK(&so->so_snd);
1419 		goto out;
1420 	}
1421 	if ((so->so_state & SS_ISCONNECTED) == 0) {
1422 		/*
1423 		 * `sendto' and `sendmsg' is allowed on a connection-based
1424 		 * socket if it supports implied connect.  Return ENOTCONN if
1425 		 * not connected and no address is supplied.
1426 		 */
1427 		if ((so->so_proto->pr_flags & PR_CONNREQUIRED) &&
1428 		    (so->so_proto->pr_flags & PR_IMPLOPCL) == 0) {
1429 			if ((so->so_state & SS_ISCONFIRMING) == 0 &&
1430 			    !(resid == 0 && clen != 0)) {
1431 				SOCKBUF_UNLOCK(&so->so_snd);
1432 				error = ENOTCONN;
1433 				goto out;
1434 			}
1435 		} else if (addr == NULL) {
1436 			if (so->so_proto->pr_flags & PR_CONNREQUIRED)
1437 				error = ENOTCONN;
1438 			else
1439 				error = EDESTADDRREQ;
1440 			SOCKBUF_UNLOCK(&so->so_snd);
1441 			goto out;
1442 		}
1443 	}
1444 
1445 	/*
1446 	 * Do we need MSG_OOB support in SOCK_DGRAM?  Signs here may be a
1447 	 * problem and need fixing.
1448 	 */
1449 	space = sbspace(&so->so_snd);
1450 	if (flags & MSG_OOB)
1451 		space += 1024;
1452 	space -= clen;
1453 	SOCKBUF_UNLOCK(&so->so_snd);
1454 	if (resid > space) {
1455 		error = EMSGSIZE;
1456 		goto out;
1457 	}
1458 	if (uio == NULL) {
1459 		resid = 0;
1460 		if (flags & MSG_EOR)
1461 			top->m_flags |= M_EOR;
1462 	} else {
1463 		/*
1464 		 * Copy the data from userland into a mbuf chain.
1465 		 * If no data is to be copied in, a single empty mbuf
1466 		 * is returned.
1467 		 */
1468 		top = m_uiotombuf(uio, M_WAITOK, space, max_hdr,
1469 		    (M_PKTHDR | ((flags & MSG_EOR) ? M_EOR : 0)));
1470 		if (top == NULL) {
1471 			error = EFAULT;	/* only possible error */
1472 			goto out;
1473 		}
1474 		space -= resid - uio->uio_resid;
1475 		resid = uio->uio_resid;
1476 	}
1477 	KASSERT(resid == 0, ("sosend_dgram: resid != 0"));
1478 	/*
1479 	 * XXXRW: Frobbing SO_DONTROUTE here is even worse without sblock
1480 	 * than with.
1481 	 */
1482 	if (dontroute) {
1483 		SOCK_LOCK(so);
1484 		so->so_options |= SO_DONTROUTE;
1485 		SOCK_UNLOCK(so);
1486 	}
1487 	/*
1488 	 * XXX all the SBS_CANTSENDMORE checks previously done could be out
1489 	 * of date.  We could have received a reset packet in an interrupt or
1490 	 * maybe we slept while doing page faults in uiomove() etc.  We could
1491 	 * probably recheck again inside the locking protection here, but
1492 	 * there are probably other places that this also happens.  We must
1493 	 * rethink this.
1494 	 */
1495 	VNET_SO_ASSERT(so);
1496 	error = (*so->so_proto->pr_usrreqs->pru_send)(so,
1497 	    (flags & MSG_OOB) ? PRUS_OOB :
1498 	/*
1499 	 * If the user set MSG_EOF, the protocol understands this flag and
1500 	 * nothing left to send then use PRU_SEND_EOF instead of PRU_SEND.
1501 	 */
1502 	    ((flags & MSG_EOF) &&
1503 	     (so->so_proto->pr_flags & PR_IMPLOPCL) &&
1504 	     (resid <= 0)) ?
1505 		PRUS_EOF :
1506 		/* If there is more to send set PRUS_MORETOCOME */
1507 		(flags & MSG_MORETOCOME) ||
1508 		(resid > 0 && space > 0) ? PRUS_MORETOCOME : 0,
1509 		top, addr, control, td);
1510 	if (dontroute) {
1511 		SOCK_LOCK(so);
1512 		so->so_options &= ~SO_DONTROUTE;
1513 		SOCK_UNLOCK(so);
1514 	}
1515 	clen = 0;
1516 	control = NULL;
1517 	top = NULL;
1518 out:
1519 	if (top != NULL)
1520 		m_freem(top);
1521 	if (control != NULL)
1522 		m_freem(control);
1523 	return (error);
1524 }
1525 
1526 /*
1527  * Send on a socket.  If send must go all at once and message is larger than
1528  * send buffering, then hard error.  Lock against other senders.  If must go
1529  * all at once and not enough room now, then inform user that this would
1530  * block and do nothing.  Otherwise, if nonblocking, send as much as
1531  * possible.  The data to be sent is described by "uio" if nonzero, otherwise
1532  * by the mbuf chain "top" (which must be null if uio is not).  Data provided
1533  * in mbuf chain must be small enough to send all at once.
1534  *
1535  * Returns nonzero on error, timeout or signal; callers must check for short
1536  * counts if EINTR/ERESTART are returned.  Data and control buffers are freed
1537  * on return.
1538  */
1539 int
1540 sosend_generic(struct socket *so, struct sockaddr *addr, struct uio *uio,
1541     struct mbuf *top, struct mbuf *control, int flags, struct thread *td)
1542 {
1543 	long space;
1544 	ssize_t resid;
1545 	int clen = 0, error, dontroute;
1546 	int atomic = sosendallatonce(so) || top;
1547 	int pru_flag;
1548 #ifdef KERN_TLS
1549 	struct ktls_session *tls;
1550 	int tls_enq_cnt, tls_pruflag;
1551 	uint8_t tls_rtype;
1552 
1553 	tls = NULL;
1554 	tls_rtype = TLS_RLTYPE_APP;
1555 #endif
1556 	if (uio != NULL)
1557 		resid = uio->uio_resid;
1558 	else if ((top->m_flags & M_PKTHDR) != 0)
1559 		resid = top->m_pkthdr.len;
1560 	else
1561 		resid = m_length(top, NULL);
1562 	/*
1563 	 * In theory resid should be unsigned.  However, space must be
1564 	 * signed, as it might be less than 0 if we over-committed, and we
1565 	 * must use a signed comparison of space and resid.  On the other
1566 	 * hand, a negative resid causes us to loop sending 0-length
1567 	 * segments to the protocol.
1568 	 *
1569 	 * Also check to make sure that MSG_EOR isn't used on SOCK_STREAM
1570 	 * type sockets since that's an error.
1571 	 */
1572 	if (resid < 0 || (so->so_type == SOCK_STREAM && (flags & MSG_EOR))) {
1573 		error = EINVAL;
1574 		goto out;
1575 	}
1576 
1577 	dontroute =
1578 	    (flags & MSG_DONTROUTE) && (so->so_options & SO_DONTROUTE) == 0 &&
1579 	    (so->so_proto->pr_flags & PR_ATOMIC);
1580 	if (td != NULL)
1581 		td->td_ru.ru_msgsnd++;
1582 	if (control != NULL)
1583 		clen = control->m_len;
1584 
1585 	error = sblock(&so->so_snd, SBLOCKWAIT(flags));
1586 	if (error)
1587 		goto out;
1588 
1589 #ifdef KERN_TLS
1590 	tls_pruflag = 0;
1591 	tls = ktls_hold(so->so_snd.sb_tls_info);
1592 	if (tls != NULL) {
1593 		if (tls->mode == TCP_TLS_MODE_SW)
1594 			tls_pruflag = PRUS_NOTREADY;
1595 
1596 		if (control != NULL) {
1597 			struct cmsghdr *cm = mtod(control, struct cmsghdr *);
1598 
1599 			if (clen >= sizeof(*cm) &&
1600 			    cm->cmsg_type == TLS_SET_RECORD_TYPE) {
1601 				tls_rtype = *((uint8_t *)CMSG_DATA(cm));
1602 				clen = 0;
1603 				m_freem(control);
1604 				control = NULL;
1605 				atomic = 1;
1606 			}
1607 		}
1608 	}
1609 #endif
1610 
1611 restart:
1612 	do {
1613 		SOCKBUF_LOCK(&so->so_snd);
1614 		if (so->so_snd.sb_state & SBS_CANTSENDMORE) {
1615 			SOCKBUF_UNLOCK(&so->so_snd);
1616 			error = EPIPE;
1617 			goto release;
1618 		}
1619 		if (so->so_error) {
1620 			error = so->so_error;
1621 			so->so_error = 0;
1622 			SOCKBUF_UNLOCK(&so->so_snd);
1623 			goto release;
1624 		}
1625 		if ((so->so_state & SS_ISCONNECTED) == 0) {
1626 			/*
1627 			 * `sendto' and `sendmsg' is allowed on a connection-
1628 			 * based socket if it supports implied connect.
1629 			 * Return ENOTCONN if not connected and no address is
1630 			 * supplied.
1631 			 */
1632 			if ((so->so_proto->pr_flags & PR_CONNREQUIRED) &&
1633 			    (so->so_proto->pr_flags & PR_IMPLOPCL) == 0) {
1634 				if ((so->so_state & SS_ISCONFIRMING) == 0 &&
1635 				    !(resid == 0 && clen != 0)) {
1636 					SOCKBUF_UNLOCK(&so->so_snd);
1637 					error = ENOTCONN;
1638 					goto release;
1639 				}
1640 			} else if (addr == NULL) {
1641 				SOCKBUF_UNLOCK(&so->so_snd);
1642 				if (so->so_proto->pr_flags & PR_CONNREQUIRED)
1643 					error = ENOTCONN;
1644 				else
1645 					error = EDESTADDRREQ;
1646 				goto release;
1647 			}
1648 		}
1649 		space = sbspace(&so->so_snd);
1650 		if (flags & MSG_OOB)
1651 			space += 1024;
1652 		if ((atomic && resid > so->so_snd.sb_hiwat) ||
1653 		    clen > so->so_snd.sb_hiwat) {
1654 			SOCKBUF_UNLOCK(&so->so_snd);
1655 			error = EMSGSIZE;
1656 			goto release;
1657 		}
1658 		if (space < resid + clen &&
1659 		    (atomic || space < so->so_snd.sb_lowat || space < clen)) {
1660 			if ((so->so_state & SS_NBIO) ||
1661 			    (flags & (MSG_NBIO | MSG_DONTWAIT)) != 0) {
1662 				SOCKBUF_UNLOCK(&so->so_snd);
1663 				error = EWOULDBLOCK;
1664 				goto release;
1665 			}
1666 			error = sbwait(&so->so_snd);
1667 			SOCKBUF_UNLOCK(&so->so_snd);
1668 			if (error)
1669 				goto release;
1670 			goto restart;
1671 		}
1672 		SOCKBUF_UNLOCK(&so->so_snd);
1673 		space -= clen;
1674 		do {
1675 			if (uio == NULL) {
1676 				resid = 0;
1677 				if (flags & MSG_EOR)
1678 					top->m_flags |= M_EOR;
1679 #ifdef KERN_TLS
1680 				if (tls != NULL) {
1681 					ktls_frame(top, tls, &tls_enq_cnt,
1682 					    tls_rtype);
1683 					tls_rtype = TLS_RLTYPE_APP;
1684 				}
1685 #endif
1686 			} else {
1687 				/*
1688 				 * Copy the data from userland into a mbuf
1689 				 * chain.  If resid is 0, which can happen
1690 				 * only if we have control to send, then
1691 				 * a single empty mbuf is returned.  This
1692 				 * is a workaround to prevent protocol send
1693 				 * methods to panic.
1694 				 */
1695 #ifdef KERN_TLS
1696 				if (tls != NULL) {
1697 					top = m_uiotombuf(uio, M_WAITOK, space,
1698 					    tls->params.max_frame_len,
1699 					    M_EXTPG |
1700 					    ((flags & MSG_EOR) ? M_EOR : 0));
1701 					if (top != NULL) {
1702 						ktls_frame(top, tls,
1703 						    &tls_enq_cnt, tls_rtype);
1704 					}
1705 					tls_rtype = TLS_RLTYPE_APP;
1706 				} else
1707 #endif
1708 					top = m_uiotombuf(uio, M_WAITOK, space,
1709 					    (atomic ? max_hdr : 0),
1710 					    (atomic ? M_PKTHDR : 0) |
1711 					    ((flags & MSG_EOR) ? M_EOR : 0));
1712 				if (top == NULL) {
1713 					error = EFAULT; /* only possible error */
1714 					goto release;
1715 				}
1716 				space -= resid - uio->uio_resid;
1717 				resid = uio->uio_resid;
1718 			}
1719 			if (dontroute) {
1720 				SOCK_LOCK(so);
1721 				so->so_options |= SO_DONTROUTE;
1722 				SOCK_UNLOCK(so);
1723 			}
1724 			/*
1725 			 * XXX all the SBS_CANTSENDMORE checks previously
1726 			 * done could be out of date.  We could have received
1727 			 * a reset packet in an interrupt or maybe we slept
1728 			 * while doing page faults in uiomove() etc.  We
1729 			 * could probably recheck again inside the locking
1730 			 * protection here, but there are probably other
1731 			 * places that this also happens.  We must rethink
1732 			 * this.
1733 			 */
1734 			VNET_SO_ASSERT(so);
1735 
1736 			pru_flag = (flags & MSG_OOB) ? PRUS_OOB :
1737 			/*
1738 			 * If the user set MSG_EOF, the protocol understands
1739 			 * this flag and nothing left to send then use
1740 			 * PRU_SEND_EOF instead of PRU_SEND.
1741 			 */
1742 			    ((flags & MSG_EOF) &&
1743 			     (so->so_proto->pr_flags & PR_IMPLOPCL) &&
1744 			     (resid <= 0)) ?
1745 				PRUS_EOF :
1746 			/* If there is more to send set PRUS_MORETOCOME. */
1747 			    (flags & MSG_MORETOCOME) ||
1748 			    (resid > 0 && space > 0) ? PRUS_MORETOCOME : 0;
1749 
1750 #ifdef KERN_TLS
1751 			pru_flag |= tls_pruflag;
1752 #endif
1753 
1754 			error = (*so->so_proto->pr_usrreqs->pru_send)(so,
1755 			    pru_flag, top, addr, control, td);
1756 
1757 			if (dontroute) {
1758 				SOCK_LOCK(so);
1759 				so->so_options &= ~SO_DONTROUTE;
1760 				SOCK_UNLOCK(so);
1761 			}
1762 
1763 #ifdef KERN_TLS
1764 			if (tls != NULL && tls->mode == TCP_TLS_MODE_SW) {
1765 				/*
1766 				 * Note that error is intentionally
1767 				 * ignored.
1768 				 *
1769 				 * Like sendfile(), we rely on the
1770 				 * completion routine (pru_ready())
1771 				 * to free the mbufs in the event that
1772 				 * pru_send() encountered an error and
1773 				 * did not append them to the sockbuf.
1774 				 */
1775 				soref(so);
1776 				ktls_enqueue(top, so, tls_enq_cnt);
1777 			}
1778 #endif
1779 			clen = 0;
1780 			control = NULL;
1781 			top = NULL;
1782 			if (error)
1783 				goto release;
1784 		} while (resid && space > 0);
1785 	} while (resid);
1786 
1787 release:
1788 	sbunlock(&so->so_snd);
1789 out:
1790 #ifdef KERN_TLS
1791 	if (tls != NULL)
1792 		ktls_free(tls);
1793 #endif
1794 	if (top != NULL)
1795 		m_freem(top);
1796 	if (control != NULL)
1797 		m_freem(control);
1798 	return (error);
1799 }
1800 
1801 int
1802 sosend(struct socket *so, struct sockaddr *addr, struct uio *uio,
1803     struct mbuf *top, struct mbuf *control, int flags, struct thread *td)
1804 {
1805 	int error;
1806 
1807 	CURVNET_SET(so->so_vnet);
1808 	if (!SOLISTENING(so))
1809 		error = so->so_proto->pr_usrreqs->pru_sosend(so, addr, uio,
1810 		    top, control, flags, td);
1811 	else {
1812 		m_freem(top);
1813 		m_freem(control);
1814 		error = ENOTCONN;
1815 	}
1816 	CURVNET_RESTORE();
1817 	return (error);
1818 }
1819 
1820 /*
1821  * The part of soreceive() that implements reading non-inline out-of-band
1822  * data from a socket.  For more complete comments, see soreceive(), from
1823  * which this code originated.
1824  *
1825  * Note that soreceive_rcvoob(), unlike the remainder of soreceive(), is
1826  * unable to return an mbuf chain to the caller.
1827  */
1828 static int
1829 soreceive_rcvoob(struct socket *so, struct uio *uio, int flags)
1830 {
1831 	struct protosw *pr = so->so_proto;
1832 	struct mbuf *m;
1833 	int error;
1834 
1835 	KASSERT(flags & MSG_OOB, ("soreceive_rcvoob: (flags & MSG_OOB) == 0"));
1836 	VNET_SO_ASSERT(so);
1837 
1838 	m = m_get(M_WAITOK, MT_DATA);
1839 	error = (*pr->pr_usrreqs->pru_rcvoob)(so, m, flags & MSG_PEEK);
1840 	if (error)
1841 		goto bad;
1842 	do {
1843 		error = uiomove(mtod(m, void *),
1844 		    (int) min(uio->uio_resid, m->m_len), uio);
1845 		m = m_free(m);
1846 	} while (uio->uio_resid && error == 0 && m);
1847 bad:
1848 	if (m != NULL)
1849 		m_freem(m);
1850 	return (error);
1851 }
1852 
1853 /*
1854  * Following replacement or removal of the first mbuf on the first mbuf chain
1855  * of a socket buffer, push necessary state changes back into the socket
1856  * buffer so that other consumers see the values consistently.  'nextrecord'
1857  * is the callers locally stored value of the original value of
1858  * sb->sb_mb->m_nextpkt which must be restored when the lead mbuf changes.
1859  * NOTE: 'nextrecord' may be NULL.
1860  */
1861 static __inline void
1862 sockbuf_pushsync(struct sockbuf *sb, struct mbuf *nextrecord)
1863 {
1864 
1865 	SOCKBUF_LOCK_ASSERT(sb);
1866 	/*
1867 	 * First, update for the new value of nextrecord.  If necessary, make
1868 	 * it the first record.
1869 	 */
1870 	if (sb->sb_mb != NULL)
1871 		sb->sb_mb->m_nextpkt = nextrecord;
1872 	else
1873 		sb->sb_mb = nextrecord;
1874 
1875 	/*
1876 	 * Now update any dependent socket buffer fields to reflect the new
1877 	 * state.  This is an expanded inline of SB_EMPTY_FIXUP(), with the
1878 	 * addition of a second clause that takes care of the case where
1879 	 * sb_mb has been updated, but remains the last record.
1880 	 */
1881 	if (sb->sb_mb == NULL) {
1882 		sb->sb_mbtail = NULL;
1883 		sb->sb_lastrecord = NULL;
1884 	} else if (sb->sb_mb->m_nextpkt == NULL)
1885 		sb->sb_lastrecord = sb->sb_mb;
1886 }
1887 
1888 /*
1889  * Implement receive operations on a socket.  We depend on the way that
1890  * records are added to the sockbuf by sbappend.  In particular, each record
1891  * (mbufs linked through m_next) must begin with an address if the protocol
1892  * so specifies, followed by an optional mbuf or mbufs containing ancillary
1893  * data, and then zero or more mbufs of data.  In order to allow parallelism
1894  * between network receive and copying to user space, as well as avoid
1895  * sleeping with a mutex held, we release the socket buffer mutex during the
1896  * user space copy.  Although the sockbuf is locked, new data may still be
1897  * appended, and thus we must maintain consistency of the sockbuf during that
1898  * time.
1899  *
1900  * The caller may receive the data as a single mbuf chain by supplying an
1901  * mbuf **mp0 for use in returning the chain.  The uio is then used only for
1902  * the count in uio_resid.
1903  */
1904 int
1905 soreceive_generic(struct socket *so, struct sockaddr **psa, struct uio *uio,
1906     struct mbuf **mp0, struct mbuf **controlp, int *flagsp)
1907 {
1908 	struct mbuf *m, **mp;
1909 	int flags, error, offset;
1910 	ssize_t len;
1911 	struct protosw *pr = so->so_proto;
1912 	struct mbuf *nextrecord;
1913 	int moff, type = 0;
1914 	ssize_t orig_resid = uio->uio_resid;
1915 
1916 	mp = mp0;
1917 	if (psa != NULL)
1918 		*psa = NULL;
1919 	if (controlp != NULL)
1920 		*controlp = NULL;
1921 	if (flagsp != NULL)
1922 		flags = *flagsp &~ MSG_EOR;
1923 	else
1924 		flags = 0;
1925 	if (flags & MSG_OOB)
1926 		return (soreceive_rcvoob(so, uio, flags));
1927 	if (mp != NULL)
1928 		*mp = NULL;
1929 	if ((pr->pr_flags & PR_WANTRCVD) && (so->so_state & SS_ISCONFIRMING)
1930 	    && uio->uio_resid) {
1931 		VNET_SO_ASSERT(so);
1932 		(*pr->pr_usrreqs->pru_rcvd)(so, 0);
1933 	}
1934 
1935 	error = sblock(&so->so_rcv, SBLOCKWAIT(flags));
1936 	if (error)
1937 		return (error);
1938 
1939 restart:
1940 	SOCKBUF_LOCK(&so->so_rcv);
1941 	m = so->so_rcv.sb_mb;
1942 	/*
1943 	 * If we have less data than requested, block awaiting more (subject
1944 	 * to any timeout) if:
1945 	 *   1. the current count is less than the low water mark, or
1946 	 *   2. MSG_DONTWAIT is not set
1947 	 */
1948 	if (m == NULL || (((flags & MSG_DONTWAIT) == 0 &&
1949 	    sbavail(&so->so_rcv) < uio->uio_resid) &&
1950 	    sbavail(&so->so_rcv) < so->so_rcv.sb_lowat &&
1951 	    m->m_nextpkt == NULL && (pr->pr_flags & PR_ATOMIC) == 0)) {
1952 		KASSERT(m != NULL || !sbavail(&so->so_rcv),
1953 		    ("receive: m == %p sbavail == %u",
1954 		    m, sbavail(&so->so_rcv)));
1955 		if (so->so_error) {
1956 			if (m != NULL)
1957 				goto dontblock;
1958 			error = so->so_error;
1959 			if ((flags & MSG_PEEK) == 0)
1960 				so->so_error = 0;
1961 			SOCKBUF_UNLOCK(&so->so_rcv);
1962 			goto release;
1963 		}
1964 		SOCKBUF_LOCK_ASSERT(&so->so_rcv);
1965 		if (so->so_rcv.sb_state & SBS_CANTRCVMORE) {
1966 			if (m != NULL)
1967 				goto dontblock;
1968 #ifdef KERN_TLS
1969 			else if (so->so_rcv.sb_tlsdcc == 0 &&
1970 			    so->so_rcv.sb_tlscc == 0) {
1971 #else
1972 			else {
1973 #endif
1974 				SOCKBUF_UNLOCK(&so->so_rcv);
1975 				goto release;
1976 			}
1977 		}
1978 		for (; m != NULL; m = m->m_next)
1979 			if (m->m_type == MT_OOBDATA  || (m->m_flags & M_EOR)) {
1980 				m = so->so_rcv.sb_mb;
1981 				goto dontblock;
1982 			}
1983 		if ((so->so_state & (SS_ISCONNECTING | SS_ISCONNECTED |
1984 		    SS_ISDISCONNECTING | SS_ISDISCONNECTED)) == 0 &&
1985 		    (so->so_proto->pr_flags & PR_CONNREQUIRED) != 0) {
1986 			SOCKBUF_UNLOCK(&so->so_rcv);
1987 			error = ENOTCONN;
1988 			goto release;
1989 		}
1990 		if (uio->uio_resid == 0) {
1991 			SOCKBUF_UNLOCK(&so->so_rcv);
1992 			goto release;
1993 		}
1994 		if ((so->so_state & SS_NBIO) ||
1995 		    (flags & (MSG_DONTWAIT|MSG_NBIO))) {
1996 			SOCKBUF_UNLOCK(&so->so_rcv);
1997 			error = EWOULDBLOCK;
1998 			goto release;
1999 		}
2000 		SBLASTRECORDCHK(&so->so_rcv);
2001 		SBLASTMBUFCHK(&so->so_rcv);
2002 		error = sbwait(&so->so_rcv);
2003 		SOCKBUF_UNLOCK(&so->so_rcv);
2004 		if (error)
2005 			goto release;
2006 		goto restart;
2007 	}
2008 dontblock:
2009 	/*
2010 	 * From this point onward, we maintain 'nextrecord' as a cache of the
2011 	 * pointer to the next record in the socket buffer.  We must keep the
2012 	 * various socket buffer pointers and local stack versions of the
2013 	 * pointers in sync, pushing out modifications before dropping the
2014 	 * socket buffer mutex, and re-reading them when picking it up.
2015 	 *
2016 	 * Otherwise, we will race with the network stack appending new data
2017 	 * or records onto the socket buffer by using inconsistent/stale
2018 	 * versions of the field, possibly resulting in socket buffer
2019 	 * corruption.
2020 	 *
2021 	 * By holding the high-level sblock(), we prevent simultaneous
2022 	 * readers from pulling off the front of the socket buffer.
2023 	 */
2024 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2025 	if (uio->uio_td)
2026 		uio->uio_td->td_ru.ru_msgrcv++;
2027 	KASSERT(m == so->so_rcv.sb_mb, ("soreceive: m != so->so_rcv.sb_mb"));
2028 	SBLASTRECORDCHK(&so->so_rcv);
2029 	SBLASTMBUFCHK(&so->so_rcv);
2030 	nextrecord = m->m_nextpkt;
2031 	if (pr->pr_flags & PR_ADDR) {
2032 		KASSERT(m->m_type == MT_SONAME,
2033 		    ("m->m_type == %d", m->m_type));
2034 		orig_resid = 0;
2035 		if (psa != NULL)
2036 			*psa = sodupsockaddr(mtod(m, struct sockaddr *),
2037 			    M_NOWAIT);
2038 		if (flags & MSG_PEEK) {
2039 			m = m->m_next;
2040 		} else {
2041 			sbfree(&so->so_rcv, m);
2042 			so->so_rcv.sb_mb = m_free(m);
2043 			m = so->so_rcv.sb_mb;
2044 			sockbuf_pushsync(&so->so_rcv, nextrecord);
2045 		}
2046 	}
2047 
2048 	/*
2049 	 * Process one or more MT_CONTROL mbufs present before any data mbufs
2050 	 * in the first mbuf chain on the socket buffer.  If MSG_PEEK, we
2051 	 * just copy the data; if !MSG_PEEK, we call into the protocol to
2052 	 * perform externalization (or freeing if controlp == NULL).
2053 	 */
2054 	if (m != NULL && m->m_type == MT_CONTROL) {
2055 		struct mbuf *cm = NULL, *cmn;
2056 		struct mbuf **cme = &cm;
2057 #ifdef KERN_TLS
2058 		struct cmsghdr *cmsg;
2059 		struct tls_get_record tgr;
2060 
2061 		/*
2062 		 * For MSG_TLSAPPDATA, check for a non-application data
2063 		 * record.  If found, return ENXIO without removing
2064 		 * it from the receive queue.  This allows a subsequent
2065 		 * call without MSG_TLSAPPDATA to receive it.
2066 		 * Note that, for TLS, there should only be a single
2067 		 * control mbuf with the TLS_GET_RECORD message in it.
2068 		 */
2069 		if (flags & MSG_TLSAPPDATA) {
2070 			cmsg = mtod(m, struct cmsghdr *);
2071 			if (cmsg->cmsg_type == TLS_GET_RECORD &&
2072 			    cmsg->cmsg_len == CMSG_LEN(sizeof(tgr))) {
2073 				memcpy(&tgr, CMSG_DATA(cmsg), sizeof(tgr));
2074 				/* This will need to change for TLS 1.3. */
2075 				if (tgr.tls_type != TLS_RLTYPE_APP) {
2076 					SOCKBUF_UNLOCK(&so->so_rcv);
2077 					error = ENXIO;
2078 					goto release;
2079 				}
2080 			}
2081 		}
2082 #endif
2083 
2084 		do {
2085 			if (flags & MSG_PEEK) {
2086 				if (controlp != NULL) {
2087 					*controlp = m_copym(m, 0, m->m_len,
2088 					    M_NOWAIT);
2089 					controlp = &(*controlp)->m_next;
2090 				}
2091 				m = m->m_next;
2092 			} else {
2093 				sbfree(&so->so_rcv, m);
2094 				so->so_rcv.sb_mb = m->m_next;
2095 				m->m_next = NULL;
2096 				*cme = m;
2097 				cme = &(*cme)->m_next;
2098 				m = so->so_rcv.sb_mb;
2099 			}
2100 		} while (m != NULL && m->m_type == MT_CONTROL);
2101 		if ((flags & MSG_PEEK) == 0)
2102 			sockbuf_pushsync(&so->so_rcv, nextrecord);
2103 		while (cm != NULL) {
2104 			cmn = cm->m_next;
2105 			cm->m_next = NULL;
2106 			if (pr->pr_domain->dom_externalize != NULL) {
2107 				SOCKBUF_UNLOCK(&so->so_rcv);
2108 				VNET_SO_ASSERT(so);
2109 				error = (*pr->pr_domain->dom_externalize)
2110 				    (cm, controlp, flags);
2111 				SOCKBUF_LOCK(&so->so_rcv);
2112 			} else if (controlp != NULL)
2113 				*controlp = cm;
2114 			else
2115 				m_freem(cm);
2116 			if (controlp != NULL) {
2117 				orig_resid = 0;
2118 				while (*controlp != NULL)
2119 					controlp = &(*controlp)->m_next;
2120 			}
2121 			cm = cmn;
2122 		}
2123 		if (m != NULL)
2124 			nextrecord = so->so_rcv.sb_mb->m_nextpkt;
2125 		else
2126 			nextrecord = so->so_rcv.sb_mb;
2127 		orig_resid = 0;
2128 	}
2129 	if (m != NULL) {
2130 		if ((flags & MSG_PEEK) == 0) {
2131 			KASSERT(m->m_nextpkt == nextrecord,
2132 			    ("soreceive: post-control, nextrecord !sync"));
2133 			if (nextrecord == NULL) {
2134 				KASSERT(so->so_rcv.sb_mb == m,
2135 				    ("soreceive: post-control, sb_mb!=m"));
2136 				KASSERT(so->so_rcv.sb_lastrecord == m,
2137 				    ("soreceive: post-control, lastrecord!=m"));
2138 			}
2139 		}
2140 		type = m->m_type;
2141 		if (type == MT_OOBDATA)
2142 			flags |= MSG_OOB;
2143 	} else {
2144 		if ((flags & MSG_PEEK) == 0) {
2145 			KASSERT(so->so_rcv.sb_mb == nextrecord,
2146 			    ("soreceive: sb_mb != nextrecord"));
2147 			if (so->so_rcv.sb_mb == NULL) {
2148 				KASSERT(so->so_rcv.sb_lastrecord == NULL,
2149 				    ("soreceive: sb_lastercord != NULL"));
2150 			}
2151 		}
2152 	}
2153 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2154 	SBLASTRECORDCHK(&so->so_rcv);
2155 	SBLASTMBUFCHK(&so->so_rcv);
2156 
2157 	/*
2158 	 * Now continue to read any data mbufs off of the head of the socket
2159 	 * buffer until the read request is satisfied.  Note that 'type' is
2160 	 * used to store the type of any mbuf reads that have happened so far
2161 	 * such that soreceive() can stop reading if the type changes, which
2162 	 * causes soreceive() to return only one of regular data and inline
2163 	 * out-of-band data in a single socket receive operation.
2164 	 */
2165 	moff = 0;
2166 	offset = 0;
2167 	while (m != NULL && !(m->m_flags & M_NOTAVAIL) && uio->uio_resid > 0
2168 	    && error == 0) {
2169 		/*
2170 		 * If the type of mbuf has changed since the last mbuf
2171 		 * examined ('type'), end the receive operation.
2172 		 */
2173 		SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2174 		if (m->m_type == MT_OOBDATA || m->m_type == MT_CONTROL) {
2175 			if (type != m->m_type)
2176 				break;
2177 		} else if (type == MT_OOBDATA)
2178 			break;
2179 		else
2180 		    KASSERT(m->m_type == MT_DATA,
2181 			("m->m_type == %d", m->m_type));
2182 		so->so_rcv.sb_state &= ~SBS_RCVATMARK;
2183 		len = uio->uio_resid;
2184 		if (so->so_oobmark && len > so->so_oobmark - offset)
2185 			len = so->so_oobmark - offset;
2186 		if (len > m->m_len - moff)
2187 			len = m->m_len - moff;
2188 		/*
2189 		 * If mp is set, just pass back the mbufs.  Otherwise copy
2190 		 * them out via the uio, then free.  Sockbuf must be
2191 		 * consistent here (points to current mbuf, it points to next
2192 		 * record) when we drop priority; we must note any additions
2193 		 * to the sockbuf when we block interrupts again.
2194 		 */
2195 		if (mp == NULL) {
2196 			SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2197 			SBLASTRECORDCHK(&so->so_rcv);
2198 			SBLASTMBUFCHK(&so->so_rcv);
2199 			SOCKBUF_UNLOCK(&so->so_rcv);
2200 			if ((m->m_flags & M_EXTPG) != 0)
2201 				error = m_unmappedtouio(m, moff, uio, (int)len);
2202 			else
2203 				error = uiomove(mtod(m, char *) + moff,
2204 				    (int)len, uio);
2205 			SOCKBUF_LOCK(&so->so_rcv);
2206 			if (error) {
2207 				/*
2208 				 * The MT_SONAME mbuf has already been removed
2209 				 * from the record, so it is necessary to
2210 				 * remove the data mbufs, if any, to preserve
2211 				 * the invariant in the case of PR_ADDR that
2212 				 * requires MT_SONAME mbufs at the head of
2213 				 * each record.
2214 				 */
2215 				if (pr->pr_flags & PR_ATOMIC &&
2216 				    ((flags & MSG_PEEK) == 0))
2217 					(void)sbdroprecord_locked(&so->so_rcv);
2218 				SOCKBUF_UNLOCK(&so->so_rcv);
2219 				goto release;
2220 			}
2221 		} else
2222 			uio->uio_resid -= len;
2223 		SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2224 		if (len == m->m_len - moff) {
2225 			if (m->m_flags & M_EOR)
2226 				flags |= MSG_EOR;
2227 			if (flags & MSG_PEEK) {
2228 				m = m->m_next;
2229 				moff = 0;
2230 			} else {
2231 				nextrecord = m->m_nextpkt;
2232 				sbfree(&so->so_rcv, m);
2233 				if (mp != NULL) {
2234 					m->m_nextpkt = NULL;
2235 					*mp = m;
2236 					mp = &m->m_next;
2237 					so->so_rcv.sb_mb = m = m->m_next;
2238 					*mp = NULL;
2239 				} else {
2240 					so->so_rcv.sb_mb = m_free(m);
2241 					m = so->so_rcv.sb_mb;
2242 				}
2243 				sockbuf_pushsync(&so->so_rcv, nextrecord);
2244 				SBLASTRECORDCHK(&so->so_rcv);
2245 				SBLASTMBUFCHK(&so->so_rcv);
2246 			}
2247 		} else {
2248 			if (flags & MSG_PEEK)
2249 				moff += len;
2250 			else {
2251 				if (mp != NULL) {
2252 					if (flags & MSG_DONTWAIT) {
2253 						*mp = m_copym(m, 0, len,
2254 						    M_NOWAIT);
2255 						if (*mp == NULL) {
2256 							/*
2257 							 * m_copym() couldn't
2258 							 * allocate an mbuf.
2259 							 * Adjust uio_resid back
2260 							 * (it was adjusted
2261 							 * down by len bytes,
2262 							 * which we didn't end
2263 							 * up "copying" over).
2264 							 */
2265 							uio->uio_resid += len;
2266 							break;
2267 						}
2268 					} else {
2269 						SOCKBUF_UNLOCK(&so->so_rcv);
2270 						*mp = m_copym(m, 0, len,
2271 						    M_WAITOK);
2272 						SOCKBUF_LOCK(&so->so_rcv);
2273 					}
2274 				}
2275 				sbcut_locked(&so->so_rcv, len);
2276 			}
2277 		}
2278 		SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2279 		if (so->so_oobmark) {
2280 			if ((flags & MSG_PEEK) == 0) {
2281 				so->so_oobmark -= len;
2282 				if (so->so_oobmark == 0) {
2283 					so->so_rcv.sb_state |= SBS_RCVATMARK;
2284 					break;
2285 				}
2286 			} else {
2287 				offset += len;
2288 				if (offset == so->so_oobmark)
2289 					break;
2290 			}
2291 		}
2292 		if (flags & MSG_EOR)
2293 			break;
2294 		/*
2295 		 * If the MSG_WAITALL flag is set (for non-atomic socket), we
2296 		 * must not quit until "uio->uio_resid == 0" or an error
2297 		 * termination.  If a signal/timeout occurs, return with a
2298 		 * short count but without error.  Keep sockbuf locked
2299 		 * against other readers.
2300 		 */
2301 		while (flags & MSG_WAITALL && m == NULL && uio->uio_resid > 0 &&
2302 		    !sosendallatonce(so) && nextrecord == NULL) {
2303 			SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2304 			if (so->so_error ||
2305 			    so->so_rcv.sb_state & SBS_CANTRCVMORE)
2306 				break;
2307 			/*
2308 			 * Notify the protocol that some data has been
2309 			 * drained before blocking.
2310 			 */
2311 			if (pr->pr_flags & PR_WANTRCVD) {
2312 				SOCKBUF_UNLOCK(&so->so_rcv);
2313 				VNET_SO_ASSERT(so);
2314 				(*pr->pr_usrreqs->pru_rcvd)(so, flags);
2315 				SOCKBUF_LOCK(&so->so_rcv);
2316 			}
2317 			SBLASTRECORDCHK(&so->so_rcv);
2318 			SBLASTMBUFCHK(&so->so_rcv);
2319 			/*
2320 			 * We could receive some data while was notifying
2321 			 * the protocol. Skip blocking in this case.
2322 			 */
2323 			if (so->so_rcv.sb_mb == NULL) {
2324 				error = sbwait(&so->so_rcv);
2325 				if (error) {
2326 					SOCKBUF_UNLOCK(&so->so_rcv);
2327 					goto release;
2328 				}
2329 			}
2330 			m = so->so_rcv.sb_mb;
2331 			if (m != NULL)
2332 				nextrecord = m->m_nextpkt;
2333 		}
2334 	}
2335 
2336 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2337 	if (m != NULL && pr->pr_flags & PR_ATOMIC) {
2338 		flags |= MSG_TRUNC;
2339 		if ((flags & MSG_PEEK) == 0)
2340 			(void) sbdroprecord_locked(&so->so_rcv);
2341 	}
2342 	if ((flags & MSG_PEEK) == 0) {
2343 		if (m == NULL) {
2344 			/*
2345 			 * First part is an inline SB_EMPTY_FIXUP().  Second
2346 			 * part makes sure sb_lastrecord is up-to-date if
2347 			 * there is still data in the socket buffer.
2348 			 */
2349 			so->so_rcv.sb_mb = nextrecord;
2350 			if (so->so_rcv.sb_mb == NULL) {
2351 				so->so_rcv.sb_mbtail = NULL;
2352 				so->so_rcv.sb_lastrecord = NULL;
2353 			} else if (nextrecord->m_nextpkt == NULL)
2354 				so->so_rcv.sb_lastrecord = nextrecord;
2355 		}
2356 		SBLASTRECORDCHK(&so->so_rcv);
2357 		SBLASTMBUFCHK(&so->so_rcv);
2358 		/*
2359 		 * If soreceive() is being done from the socket callback,
2360 		 * then don't need to generate ACK to peer to update window,
2361 		 * since ACK will be generated on return to TCP.
2362 		 */
2363 		if (!(flags & MSG_SOCALLBCK) &&
2364 		    (pr->pr_flags & PR_WANTRCVD)) {
2365 			SOCKBUF_UNLOCK(&so->so_rcv);
2366 			VNET_SO_ASSERT(so);
2367 			(*pr->pr_usrreqs->pru_rcvd)(so, flags);
2368 			SOCKBUF_LOCK(&so->so_rcv);
2369 		}
2370 	}
2371 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2372 	if (orig_resid == uio->uio_resid && orig_resid &&
2373 	    (flags & MSG_EOR) == 0 && (so->so_rcv.sb_state & SBS_CANTRCVMORE) == 0) {
2374 		SOCKBUF_UNLOCK(&so->so_rcv);
2375 		goto restart;
2376 	}
2377 	SOCKBUF_UNLOCK(&so->so_rcv);
2378 
2379 	if (flagsp != NULL)
2380 		*flagsp |= flags;
2381 release:
2382 	sbunlock(&so->so_rcv);
2383 	return (error);
2384 }
2385 
2386 /*
2387  * Optimized version of soreceive() for stream (TCP) sockets.
2388  */
2389 int
2390 soreceive_stream(struct socket *so, struct sockaddr **psa, struct uio *uio,
2391     struct mbuf **mp0, struct mbuf **controlp, int *flagsp)
2392 {
2393 	int len = 0, error = 0, flags, oresid;
2394 	struct sockbuf *sb;
2395 	struct mbuf *m, *n = NULL;
2396 
2397 	/* We only do stream sockets. */
2398 	if (so->so_type != SOCK_STREAM)
2399 		return (EINVAL);
2400 	if (psa != NULL)
2401 		*psa = NULL;
2402 	if (flagsp != NULL)
2403 		flags = *flagsp &~ MSG_EOR;
2404 	else
2405 		flags = 0;
2406 	if (controlp != NULL)
2407 		*controlp = NULL;
2408 	if (flags & MSG_OOB)
2409 		return (soreceive_rcvoob(so, uio, flags));
2410 	if (mp0 != NULL)
2411 		*mp0 = NULL;
2412 
2413 	sb = &so->so_rcv;
2414 
2415 #ifdef KERN_TLS
2416 	/*
2417 	 * KTLS store TLS records as records with a control message to
2418 	 * describe the framing.
2419 	 *
2420 	 * We check once here before acquiring locks to optimize the
2421 	 * common case.
2422 	 */
2423 	if (sb->sb_tls_info != NULL)
2424 		return (soreceive_generic(so, psa, uio, mp0, controlp,
2425 		    flagsp));
2426 #endif
2427 
2428 	/* Prevent other readers from entering the socket. */
2429 	error = sblock(sb, SBLOCKWAIT(flags));
2430 	if (error)
2431 		return (error);
2432 	SOCKBUF_LOCK(sb);
2433 
2434 #ifdef KERN_TLS
2435 	if (sb->sb_tls_info != NULL) {
2436 		SOCKBUF_UNLOCK(sb);
2437 		sbunlock(sb);
2438 		return (soreceive_generic(so, psa, uio, mp0, controlp,
2439 		    flagsp));
2440 	}
2441 #endif
2442 
2443 	/* Easy one, no space to copyout anything. */
2444 	if (uio->uio_resid == 0) {
2445 		error = EINVAL;
2446 		goto out;
2447 	}
2448 	oresid = uio->uio_resid;
2449 
2450 	/* We will never ever get anything unless we are or were connected. */
2451 	if (!(so->so_state & (SS_ISCONNECTED|SS_ISDISCONNECTED))) {
2452 		error = ENOTCONN;
2453 		goto out;
2454 	}
2455 
2456 restart:
2457 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2458 
2459 	/* Abort if socket has reported problems. */
2460 	if (so->so_error) {
2461 		if (sbavail(sb) > 0)
2462 			goto deliver;
2463 		if (oresid > uio->uio_resid)
2464 			goto out;
2465 		error = so->so_error;
2466 		if (!(flags & MSG_PEEK))
2467 			so->so_error = 0;
2468 		goto out;
2469 	}
2470 
2471 	/* Door is closed.  Deliver what is left, if any. */
2472 	if (sb->sb_state & SBS_CANTRCVMORE) {
2473 		if (sbavail(sb) > 0)
2474 			goto deliver;
2475 		else
2476 			goto out;
2477 	}
2478 
2479 	/* Socket buffer is empty and we shall not block. */
2480 	if (sbavail(sb) == 0 &&
2481 	    ((so->so_state & SS_NBIO) || (flags & (MSG_DONTWAIT|MSG_NBIO)))) {
2482 		error = EAGAIN;
2483 		goto out;
2484 	}
2485 
2486 	/* Socket buffer got some data that we shall deliver now. */
2487 	if (sbavail(sb) > 0 && !(flags & MSG_WAITALL) &&
2488 	    ((so->so_state & SS_NBIO) ||
2489 	     (flags & (MSG_DONTWAIT|MSG_NBIO)) ||
2490 	     sbavail(sb) >= sb->sb_lowat ||
2491 	     sbavail(sb) >= uio->uio_resid ||
2492 	     sbavail(sb) >= sb->sb_hiwat) ) {
2493 		goto deliver;
2494 	}
2495 
2496 	/* On MSG_WAITALL we must wait until all data or error arrives. */
2497 	if ((flags & MSG_WAITALL) &&
2498 	    (sbavail(sb) >= uio->uio_resid || sbavail(sb) >= sb->sb_hiwat))
2499 		goto deliver;
2500 
2501 	/*
2502 	 * Wait and block until (more) data comes in.
2503 	 * NB: Drops the sockbuf lock during wait.
2504 	 */
2505 	error = sbwait(sb);
2506 	if (error)
2507 		goto out;
2508 	goto restart;
2509 
2510 deliver:
2511 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2512 	KASSERT(sbavail(sb) > 0, ("%s: sockbuf empty", __func__));
2513 	KASSERT(sb->sb_mb != NULL, ("%s: sb_mb == NULL", __func__));
2514 
2515 	/* Statistics. */
2516 	if (uio->uio_td)
2517 		uio->uio_td->td_ru.ru_msgrcv++;
2518 
2519 	/* Fill uio until full or current end of socket buffer is reached. */
2520 	len = min(uio->uio_resid, sbavail(sb));
2521 	if (mp0 != NULL) {
2522 		/* Dequeue as many mbufs as possible. */
2523 		if (!(flags & MSG_PEEK) && len >= sb->sb_mb->m_len) {
2524 			if (*mp0 == NULL)
2525 				*mp0 = sb->sb_mb;
2526 			else
2527 				m_cat(*mp0, sb->sb_mb);
2528 			for (m = sb->sb_mb;
2529 			     m != NULL && m->m_len <= len;
2530 			     m = m->m_next) {
2531 				KASSERT(!(m->m_flags & M_NOTAVAIL),
2532 				    ("%s: m %p not available", __func__, m));
2533 				len -= m->m_len;
2534 				uio->uio_resid -= m->m_len;
2535 				sbfree(sb, m);
2536 				n = m;
2537 			}
2538 			n->m_next = NULL;
2539 			sb->sb_mb = m;
2540 			sb->sb_lastrecord = sb->sb_mb;
2541 			if (sb->sb_mb == NULL)
2542 				SB_EMPTY_FIXUP(sb);
2543 		}
2544 		/* Copy the remainder. */
2545 		if (len > 0) {
2546 			KASSERT(sb->sb_mb != NULL,
2547 			    ("%s: len > 0 && sb->sb_mb empty", __func__));
2548 
2549 			m = m_copym(sb->sb_mb, 0, len, M_NOWAIT);
2550 			if (m == NULL)
2551 				len = 0;	/* Don't flush data from sockbuf. */
2552 			else
2553 				uio->uio_resid -= len;
2554 			if (*mp0 != NULL)
2555 				m_cat(*mp0, m);
2556 			else
2557 				*mp0 = m;
2558 			if (*mp0 == NULL) {
2559 				error = ENOBUFS;
2560 				goto out;
2561 			}
2562 		}
2563 	} else {
2564 		/* NB: Must unlock socket buffer as uiomove may sleep. */
2565 		SOCKBUF_UNLOCK(sb);
2566 		error = m_mbuftouio(uio, sb->sb_mb, len);
2567 		SOCKBUF_LOCK(sb);
2568 		if (error)
2569 			goto out;
2570 	}
2571 	SBLASTRECORDCHK(sb);
2572 	SBLASTMBUFCHK(sb);
2573 
2574 	/*
2575 	 * Remove the delivered data from the socket buffer unless we
2576 	 * were only peeking.
2577 	 */
2578 	if (!(flags & MSG_PEEK)) {
2579 		if (len > 0)
2580 			sbdrop_locked(sb, len);
2581 
2582 		/* Notify protocol that we drained some data. */
2583 		if ((so->so_proto->pr_flags & PR_WANTRCVD) &&
2584 		    (((flags & MSG_WAITALL) && uio->uio_resid > 0) ||
2585 		     !(flags & MSG_SOCALLBCK))) {
2586 			SOCKBUF_UNLOCK(sb);
2587 			VNET_SO_ASSERT(so);
2588 			(*so->so_proto->pr_usrreqs->pru_rcvd)(so, flags);
2589 			SOCKBUF_LOCK(sb);
2590 		}
2591 	}
2592 
2593 	/*
2594 	 * For MSG_WAITALL we may have to loop again and wait for
2595 	 * more data to come in.
2596 	 */
2597 	if ((flags & MSG_WAITALL) && uio->uio_resid > 0)
2598 		goto restart;
2599 out:
2600 	SOCKBUF_LOCK_ASSERT(sb);
2601 	SBLASTRECORDCHK(sb);
2602 	SBLASTMBUFCHK(sb);
2603 	SOCKBUF_UNLOCK(sb);
2604 	sbunlock(sb);
2605 	return (error);
2606 }
2607 
2608 /*
2609  * Optimized version of soreceive() for simple datagram cases from userspace.
2610  * Unlike in the stream case, we're able to drop a datagram if copyout()
2611  * fails, and because we handle datagrams atomically, we don't need to use a
2612  * sleep lock to prevent I/O interlacing.
2613  */
2614 int
2615 soreceive_dgram(struct socket *so, struct sockaddr **psa, struct uio *uio,
2616     struct mbuf **mp0, struct mbuf **controlp, int *flagsp)
2617 {
2618 	struct mbuf *m, *m2;
2619 	int flags, error;
2620 	ssize_t len;
2621 	struct protosw *pr = so->so_proto;
2622 	struct mbuf *nextrecord;
2623 
2624 	if (psa != NULL)
2625 		*psa = NULL;
2626 	if (controlp != NULL)
2627 		*controlp = NULL;
2628 	if (flagsp != NULL)
2629 		flags = *flagsp &~ MSG_EOR;
2630 	else
2631 		flags = 0;
2632 
2633 	/*
2634 	 * For any complicated cases, fall back to the full
2635 	 * soreceive_generic().
2636 	 */
2637 	if (mp0 != NULL || (flags & MSG_PEEK) || (flags & MSG_OOB))
2638 		return (soreceive_generic(so, psa, uio, mp0, controlp,
2639 		    flagsp));
2640 
2641 	/*
2642 	 * Enforce restrictions on use.
2643 	 */
2644 	KASSERT((pr->pr_flags & PR_WANTRCVD) == 0,
2645 	    ("soreceive_dgram: wantrcvd"));
2646 	KASSERT(pr->pr_flags & PR_ATOMIC, ("soreceive_dgram: !atomic"));
2647 	KASSERT((so->so_rcv.sb_state & SBS_RCVATMARK) == 0,
2648 	    ("soreceive_dgram: SBS_RCVATMARK"));
2649 	KASSERT((so->so_proto->pr_flags & PR_CONNREQUIRED) == 0,
2650 	    ("soreceive_dgram: P_CONNREQUIRED"));
2651 
2652 	/*
2653 	 * Loop blocking while waiting for a datagram.
2654 	 */
2655 	SOCKBUF_LOCK(&so->so_rcv);
2656 	while ((m = so->so_rcv.sb_mb) == NULL) {
2657 		KASSERT(sbavail(&so->so_rcv) == 0,
2658 		    ("soreceive_dgram: sb_mb NULL but sbavail %u",
2659 		    sbavail(&so->so_rcv)));
2660 		if (so->so_error) {
2661 			error = so->so_error;
2662 			so->so_error = 0;
2663 			SOCKBUF_UNLOCK(&so->so_rcv);
2664 			return (error);
2665 		}
2666 		if (so->so_rcv.sb_state & SBS_CANTRCVMORE ||
2667 		    uio->uio_resid == 0) {
2668 			SOCKBUF_UNLOCK(&so->so_rcv);
2669 			return (0);
2670 		}
2671 		if ((so->so_state & SS_NBIO) ||
2672 		    (flags & (MSG_DONTWAIT|MSG_NBIO))) {
2673 			SOCKBUF_UNLOCK(&so->so_rcv);
2674 			return (EWOULDBLOCK);
2675 		}
2676 		SBLASTRECORDCHK(&so->so_rcv);
2677 		SBLASTMBUFCHK(&so->so_rcv);
2678 		error = sbwait(&so->so_rcv);
2679 		if (error) {
2680 			SOCKBUF_UNLOCK(&so->so_rcv);
2681 			return (error);
2682 		}
2683 	}
2684 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
2685 
2686 	if (uio->uio_td)
2687 		uio->uio_td->td_ru.ru_msgrcv++;
2688 	SBLASTRECORDCHK(&so->so_rcv);
2689 	SBLASTMBUFCHK(&so->so_rcv);
2690 	nextrecord = m->m_nextpkt;
2691 	if (nextrecord == NULL) {
2692 		KASSERT(so->so_rcv.sb_lastrecord == m,
2693 		    ("soreceive_dgram: lastrecord != m"));
2694 	}
2695 
2696 	KASSERT(so->so_rcv.sb_mb->m_nextpkt == nextrecord,
2697 	    ("soreceive_dgram: m_nextpkt != nextrecord"));
2698 
2699 	/*
2700 	 * Pull 'm' and its chain off the front of the packet queue.
2701 	 */
2702 	so->so_rcv.sb_mb = NULL;
2703 	sockbuf_pushsync(&so->so_rcv, nextrecord);
2704 
2705 	/*
2706 	 * Walk 'm's chain and free that many bytes from the socket buffer.
2707 	 */
2708 	for (m2 = m; m2 != NULL; m2 = m2->m_next)
2709 		sbfree(&so->so_rcv, m2);
2710 
2711 	/*
2712 	 * Do a few last checks before we let go of the lock.
2713 	 */
2714 	SBLASTRECORDCHK(&so->so_rcv);
2715 	SBLASTMBUFCHK(&so->so_rcv);
2716 	SOCKBUF_UNLOCK(&so->so_rcv);
2717 
2718 	if (pr->pr_flags & PR_ADDR) {
2719 		KASSERT(m->m_type == MT_SONAME,
2720 		    ("m->m_type == %d", m->m_type));
2721 		if (psa != NULL)
2722 			*psa = sodupsockaddr(mtod(m, struct sockaddr *),
2723 			    M_NOWAIT);
2724 		m = m_free(m);
2725 	}
2726 	if (m == NULL) {
2727 		/* XXXRW: Can this happen? */
2728 		return (0);
2729 	}
2730 
2731 	/*
2732 	 * Packet to copyout() is now in 'm' and it is disconnected from the
2733 	 * queue.
2734 	 *
2735 	 * Process one or more MT_CONTROL mbufs present before any data mbufs
2736 	 * in the first mbuf chain on the socket buffer.  We call into the
2737 	 * protocol to perform externalization (or freeing if controlp ==
2738 	 * NULL). In some cases there can be only MT_CONTROL mbufs without
2739 	 * MT_DATA mbufs.
2740 	 */
2741 	if (m->m_type == MT_CONTROL) {
2742 		struct mbuf *cm = NULL, *cmn;
2743 		struct mbuf **cme = &cm;
2744 
2745 		do {
2746 			m2 = m->m_next;
2747 			m->m_next = NULL;
2748 			*cme = m;
2749 			cme = &(*cme)->m_next;
2750 			m = m2;
2751 		} while (m != NULL && m->m_type == MT_CONTROL);
2752 		while (cm != NULL) {
2753 			cmn = cm->m_next;
2754 			cm->m_next = NULL;
2755 			if (pr->pr_domain->dom_externalize != NULL) {
2756 				error = (*pr->pr_domain->dom_externalize)
2757 				    (cm, controlp, flags);
2758 			} else if (controlp != NULL)
2759 				*controlp = cm;
2760 			else
2761 				m_freem(cm);
2762 			if (controlp != NULL) {
2763 				while (*controlp != NULL)
2764 					controlp = &(*controlp)->m_next;
2765 			}
2766 			cm = cmn;
2767 		}
2768 	}
2769 	KASSERT(m == NULL || m->m_type == MT_DATA,
2770 	    ("soreceive_dgram: !data"));
2771 	while (m != NULL && uio->uio_resid > 0) {
2772 		len = uio->uio_resid;
2773 		if (len > m->m_len)
2774 			len = m->m_len;
2775 		error = uiomove(mtod(m, char *), (int)len, uio);
2776 		if (error) {
2777 			m_freem(m);
2778 			return (error);
2779 		}
2780 		if (len == m->m_len)
2781 			m = m_free(m);
2782 		else {
2783 			m->m_data += len;
2784 			m->m_len -= len;
2785 		}
2786 	}
2787 	if (m != NULL) {
2788 		flags |= MSG_TRUNC;
2789 		m_freem(m);
2790 	}
2791 	if (flagsp != NULL)
2792 		*flagsp |= flags;
2793 	return (0);
2794 }
2795 
2796 int
2797 soreceive(struct socket *so, struct sockaddr **psa, struct uio *uio,
2798     struct mbuf **mp0, struct mbuf **controlp, int *flagsp)
2799 {
2800 	int error;
2801 
2802 	CURVNET_SET(so->so_vnet);
2803 	if (!SOLISTENING(so))
2804 		error = (so->so_proto->pr_usrreqs->pru_soreceive(so, psa, uio,
2805 		    mp0, controlp, flagsp));
2806 	else
2807 		error = ENOTCONN;
2808 	CURVNET_RESTORE();
2809 	return (error);
2810 }
2811 
2812 int
2813 soshutdown(struct socket *so, int how)
2814 {
2815 	struct protosw *pr = so->so_proto;
2816 	int error, soerror_enotconn;
2817 
2818 	if (!(how == SHUT_RD || how == SHUT_WR || how == SHUT_RDWR))
2819 		return (EINVAL);
2820 
2821 	soerror_enotconn = 0;
2822 	if ((so->so_state &
2823 	    (SS_ISCONNECTED | SS_ISCONNECTING | SS_ISDISCONNECTING)) == 0) {
2824 		/*
2825 		 * POSIX mandates us to return ENOTCONN when shutdown(2) is
2826 		 * invoked on a datagram sockets, however historically we would
2827 		 * actually tear socket down. This is known to be leveraged by
2828 		 * some applications to unblock process waiting in recvXXX(2)
2829 		 * by other process that it shares that socket with. Try to meet
2830 		 * both backward-compatibility and POSIX requirements by forcing
2831 		 * ENOTCONN but still asking protocol to perform pru_shutdown().
2832 		 */
2833 		if (so->so_type != SOCK_DGRAM && !SOLISTENING(so))
2834 			return (ENOTCONN);
2835 		soerror_enotconn = 1;
2836 	}
2837 
2838 	if (SOLISTENING(so)) {
2839 		if (how != SHUT_WR) {
2840 			SOLISTEN_LOCK(so);
2841 			so->so_error = ECONNABORTED;
2842 			solisten_wakeup(so);	/* unlocks so */
2843 		}
2844 		goto done;
2845 	}
2846 
2847 	CURVNET_SET(so->so_vnet);
2848 	if (pr->pr_usrreqs->pru_flush != NULL)
2849 		(*pr->pr_usrreqs->pru_flush)(so, how);
2850 	if (how != SHUT_WR)
2851 		sorflush(so);
2852 	if (how != SHUT_RD) {
2853 		error = (*pr->pr_usrreqs->pru_shutdown)(so);
2854 		wakeup(&so->so_timeo);
2855 		CURVNET_RESTORE();
2856 		return ((error == 0 && soerror_enotconn) ? ENOTCONN : error);
2857 	}
2858 	wakeup(&so->so_timeo);
2859 	CURVNET_RESTORE();
2860 
2861 done:
2862 	return (soerror_enotconn ? ENOTCONN : 0);
2863 }
2864 
2865 void
2866 sorflush(struct socket *so)
2867 {
2868 	struct sockbuf *sb = &so->so_rcv;
2869 	struct protosw *pr = so->so_proto;
2870 	struct socket aso;
2871 
2872 	VNET_SO_ASSERT(so);
2873 
2874 	/*
2875 	 * In order to avoid calling dom_dispose with the socket buffer mutex
2876 	 * held, and in order to generally avoid holding the lock for a long
2877 	 * time, we make a copy of the socket buffer and clear the original
2878 	 * (except locks, state).  The new socket buffer copy won't have
2879 	 * initialized locks so we can only call routines that won't use or
2880 	 * assert those locks.
2881 	 *
2882 	 * Dislodge threads currently blocked in receive and wait to acquire
2883 	 * a lock against other simultaneous readers before clearing the
2884 	 * socket buffer.  Don't let our acquire be interrupted by a signal
2885 	 * despite any existing socket disposition on interruptable waiting.
2886 	 */
2887 	socantrcvmore(so);
2888 	(void) sblock(sb, SBL_WAIT | SBL_NOINTR);
2889 
2890 	/*
2891 	 * Invalidate/clear most of the sockbuf structure, but leave selinfo
2892 	 * and mutex data unchanged.
2893 	 */
2894 	SOCKBUF_LOCK(sb);
2895 	bzero(&aso, sizeof(aso));
2896 	aso.so_pcb = so->so_pcb;
2897 	bcopy(&sb->sb_startzero, &aso.so_rcv.sb_startzero,
2898 	    sizeof(*sb) - offsetof(struct sockbuf, sb_startzero));
2899 	bzero(&sb->sb_startzero,
2900 	    sizeof(*sb) - offsetof(struct sockbuf, sb_startzero));
2901 	SOCKBUF_UNLOCK(sb);
2902 	sbunlock(sb);
2903 
2904 	/*
2905 	 * Dispose of special rights and flush the copied socket.  Don't call
2906 	 * any unsafe routines (that rely on locks being initialized) on aso.
2907 	 */
2908 	if (pr->pr_flags & PR_RIGHTS && pr->pr_domain->dom_dispose != NULL)
2909 		(*pr->pr_domain->dom_dispose)(&aso);
2910 	sbrelease_internal(&aso.so_rcv, so);
2911 }
2912 
2913 /*
2914  * Wrapper for Socket established helper hook.
2915  * Parameters: socket, context of the hook point, hook id.
2916  */
2917 static int inline
2918 hhook_run_socket(struct socket *so, void *hctx, int32_t h_id)
2919 {
2920 	struct socket_hhook_data hhook_data = {
2921 		.so = so,
2922 		.hctx = hctx,
2923 		.m = NULL,
2924 		.status = 0
2925 	};
2926 
2927 	CURVNET_SET(so->so_vnet);
2928 	HHOOKS_RUN_IF(V_socket_hhh[h_id], &hhook_data, &so->osd);
2929 	CURVNET_RESTORE();
2930 
2931 	/* Ugly but needed, since hhooks return void for now */
2932 	return (hhook_data.status);
2933 }
2934 
2935 /*
2936  * Perhaps this routine, and sooptcopyout(), below, ought to come in an
2937  * additional variant to handle the case where the option value needs to be
2938  * some kind of integer, but not a specific size.  In addition to their use
2939  * here, these functions are also called by the protocol-level pr_ctloutput()
2940  * routines.
2941  */
2942 int
2943 sooptcopyin(struct sockopt *sopt, void *buf, size_t len, size_t minlen)
2944 {
2945 	size_t	valsize;
2946 
2947 	/*
2948 	 * If the user gives us more than we wanted, we ignore it, but if we
2949 	 * don't get the minimum length the caller wants, we return EINVAL.
2950 	 * On success, sopt->sopt_valsize is set to however much we actually
2951 	 * retrieved.
2952 	 */
2953 	if ((valsize = sopt->sopt_valsize) < minlen)
2954 		return EINVAL;
2955 	if (valsize > len)
2956 		sopt->sopt_valsize = valsize = len;
2957 
2958 	if (sopt->sopt_td != NULL)
2959 		return (copyin(sopt->sopt_val, buf, valsize));
2960 
2961 	bcopy(sopt->sopt_val, buf, valsize);
2962 	return (0);
2963 }
2964 
2965 /*
2966  * Kernel version of setsockopt(2).
2967  *
2968  * XXX: optlen is size_t, not socklen_t
2969  */
2970 int
2971 so_setsockopt(struct socket *so, int level, int optname, void *optval,
2972     size_t optlen)
2973 {
2974 	struct sockopt sopt;
2975 
2976 	sopt.sopt_level = level;
2977 	sopt.sopt_name = optname;
2978 	sopt.sopt_dir = SOPT_SET;
2979 	sopt.sopt_val = optval;
2980 	sopt.sopt_valsize = optlen;
2981 	sopt.sopt_td = NULL;
2982 	return (sosetopt(so, &sopt));
2983 }
2984 
2985 int
2986 sosetopt(struct socket *so, struct sockopt *sopt)
2987 {
2988 	int	error, optval;
2989 	struct	linger l;
2990 	struct	timeval tv;
2991 	sbintime_t val;
2992 	uint32_t val32;
2993 #ifdef MAC
2994 	struct mac extmac;
2995 #endif
2996 
2997 	CURVNET_SET(so->so_vnet);
2998 	error = 0;
2999 	if (sopt->sopt_level != SOL_SOCKET) {
3000 		if (so->so_proto->pr_ctloutput != NULL)
3001 			error = (*so->so_proto->pr_ctloutput)(so, sopt);
3002 		else
3003 			error = ENOPROTOOPT;
3004 	} else {
3005 		switch (sopt->sopt_name) {
3006 		case SO_ACCEPTFILTER:
3007 			error = accept_filt_setopt(so, sopt);
3008 			if (error)
3009 				goto bad;
3010 			break;
3011 
3012 		case SO_LINGER:
3013 			error = sooptcopyin(sopt, &l, sizeof l, sizeof l);
3014 			if (error)
3015 				goto bad;
3016 			if (l.l_linger < 0 ||
3017 			    l.l_linger > USHRT_MAX ||
3018 			    l.l_linger > (INT_MAX / hz)) {
3019 				error = EDOM;
3020 				goto bad;
3021 			}
3022 			SOCK_LOCK(so);
3023 			so->so_linger = l.l_linger;
3024 			if (l.l_onoff)
3025 				so->so_options |= SO_LINGER;
3026 			else
3027 				so->so_options &= ~SO_LINGER;
3028 			SOCK_UNLOCK(so);
3029 			break;
3030 
3031 		case SO_DEBUG:
3032 		case SO_KEEPALIVE:
3033 		case SO_DONTROUTE:
3034 		case SO_USELOOPBACK:
3035 		case SO_BROADCAST:
3036 		case SO_REUSEADDR:
3037 		case SO_REUSEPORT:
3038 		case SO_REUSEPORT_LB:
3039 		case SO_OOBINLINE:
3040 		case SO_TIMESTAMP:
3041 		case SO_BINTIME:
3042 		case SO_NOSIGPIPE:
3043 		case SO_NO_DDP:
3044 		case SO_NO_OFFLOAD:
3045 			error = sooptcopyin(sopt, &optval, sizeof optval,
3046 			    sizeof optval);
3047 			if (error)
3048 				goto bad;
3049 			SOCK_LOCK(so);
3050 			if (optval)
3051 				so->so_options |= sopt->sopt_name;
3052 			else
3053 				so->so_options &= ~sopt->sopt_name;
3054 			SOCK_UNLOCK(so);
3055 			break;
3056 
3057 		case SO_SETFIB:
3058 			error = sooptcopyin(sopt, &optval, sizeof optval,
3059 			    sizeof optval);
3060 			if (error)
3061 				goto bad;
3062 
3063 			if (optval < 0 || optval >= rt_numfibs) {
3064 				error = EINVAL;
3065 				goto bad;
3066 			}
3067 			if (((so->so_proto->pr_domain->dom_family == PF_INET) ||
3068 			   (so->so_proto->pr_domain->dom_family == PF_INET6) ||
3069 			   (so->so_proto->pr_domain->dom_family == PF_ROUTE)))
3070 				so->so_fibnum = optval;
3071 			else
3072 				so->so_fibnum = 0;
3073 			break;
3074 
3075 		case SO_USER_COOKIE:
3076 			error = sooptcopyin(sopt, &val32, sizeof val32,
3077 			    sizeof val32);
3078 			if (error)
3079 				goto bad;
3080 			so->so_user_cookie = val32;
3081 			break;
3082 
3083 		case SO_SNDBUF:
3084 		case SO_RCVBUF:
3085 		case SO_SNDLOWAT:
3086 		case SO_RCVLOWAT:
3087 			error = sooptcopyin(sopt, &optval, sizeof optval,
3088 			    sizeof optval);
3089 			if (error)
3090 				goto bad;
3091 
3092 			/*
3093 			 * Values < 1 make no sense for any of these options,
3094 			 * so disallow them.
3095 			 */
3096 			if (optval < 1) {
3097 				error = EINVAL;
3098 				goto bad;
3099 			}
3100 
3101 			error = sbsetopt(so, sopt->sopt_name, optval);
3102 			break;
3103 
3104 		case SO_SNDTIMEO:
3105 		case SO_RCVTIMEO:
3106 #ifdef COMPAT_FREEBSD32
3107 			if (SV_CURPROC_FLAG(SV_ILP32)) {
3108 				struct timeval32 tv32;
3109 
3110 				error = sooptcopyin(sopt, &tv32, sizeof tv32,
3111 				    sizeof tv32);
3112 				CP(tv32, tv, tv_sec);
3113 				CP(tv32, tv, tv_usec);
3114 			} else
3115 #endif
3116 				error = sooptcopyin(sopt, &tv, sizeof tv,
3117 				    sizeof tv);
3118 			if (error)
3119 				goto bad;
3120 			if (tv.tv_sec < 0 || tv.tv_usec < 0 ||
3121 			    tv.tv_usec >= 1000000) {
3122 				error = EDOM;
3123 				goto bad;
3124 			}
3125 			if (tv.tv_sec > INT32_MAX)
3126 				val = SBT_MAX;
3127 			else
3128 				val = tvtosbt(tv);
3129 			switch (sopt->sopt_name) {
3130 			case SO_SNDTIMEO:
3131 				so->so_snd.sb_timeo = val;
3132 				break;
3133 			case SO_RCVTIMEO:
3134 				so->so_rcv.sb_timeo = val;
3135 				break;
3136 			}
3137 			break;
3138 
3139 		case SO_LABEL:
3140 #ifdef MAC
3141 			error = sooptcopyin(sopt, &extmac, sizeof extmac,
3142 			    sizeof extmac);
3143 			if (error)
3144 				goto bad;
3145 			error = mac_setsockopt_label(sopt->sopt_td->td_ucred,
3146 			    so, &extmac);
3147 #else
3148 			error = EOPNOTSUPP;
3149 #endif
3150 			break;
3151 
3152 		case SO_TS_CLOCK:
3153 			error = sooptcopyin(sopt, &optval, sizeof optval,
3154 			    sizeof optval);
3155 			if (error)
3156 				goto bad;
3157 			if (optval < 0 || optval > SO_TS_CLOCK_MAX) {
3158 				error = EINVAL;
3159 				goto bad;
3160 			}
3161 			so->so_ts_clock = optval;
3162 			break;
3163 
3164 		case SO_MAX_PACING_RATE:
3165 			error = sooptcopyin(sopt, &val32, sizeof(val32),
3166 			    sizeof(val32));
3167 			if (error)
3168 				goto bad;
3169 			so->so_max_pacing_rate = val32;
3170 			break;
3171 
3172 		default:
3173 			if (V_socket_hhh[HHOOK_SOCKET_OPT]->hhh_nhooks > 0)
3174 				error = hhook_run_socket(so, sopt,
3175 				    HHOOK_SOCKET_OPT);
3176 			else
3177 				error = ENOPROTOOPT;
3178 			break;
3179 		}
3180 		if (error == 0 && so->so_proto->pr_ctloutput != NULL)
3181 			(void)(*so->so_proto->pr_ctloutput)(so, sopt);
3182 	}
3183 bad:
3184 	CURVNET_RESTORE();
3185 	return (error);
3186 }
3187 
3188 /*
3189  * Helper routine for getsockopt.
3190  */
3191 int
3192 sooptcopyout(struct sockopt *sopt, const void *buf, size_t len)
3193 {
3194 	int	error;
3195 	size_t	valsize;
3196 
3197 	error = 0;
3198 
3199 	/*
3200 	 * Documented get behavior is that we always return a value, possibly
3201 	 * truncated to fit in the user's buffer.  Traditional behavior is
3202 	 * that we always tell the user precisely how much we copied, rather
3203 	 * than something useful like the total amount we had available for
3204 	 * her.  Note that this interface is not idempotent; the entire
3205 	 * answer must be generated ahead of time.
3206 	 */
3207 	valsize = min(len, sopt->sopt_valsize);
3208 	sopt->sopt_valsize = valsize;
3209 	if (sopt->sopt_val != NULL) {
3210 		if (sopt->sopt_td != NULL)
3211 			error = copyout(buf, sopt->sopt_val, valsize);
3212 		else
3213 			bcopy(buf, sopt->sopt_val, valsize);
3214 	}
3215 	return (error);
3216 }
3217 
3218 int
3219 sogetopt(struct socket *so, struct sockopt *sopt)
3220 {
3221 	int	error, optval;
3222 	struct	linger l;
3223 	struct	timeval tv;
3224 #ifdef MAC
3225 	struct mac extmac;
3226 #endif
3227 
3228 	CURVNET_SET(so->so_vnet);
3229 	error = 0;
3230 	if (sopt->sopt_level != SOL_SOCKET) {
3231 		if (so->so_proto->pr_ctloutput != NULL)
3232 			error = (*so->so_proto->pr_ctloutput)(so, sopt);
3233 		else
3234 			error = ENOPROTOOPT;
3235 		CURVNET_RESTORE();
3236 		return (error);
3237 	} else {
3238 		switch (sopt->sopt_name) {
3239 		case SO_ACCEPTFILTER:
3240 			error = accept_filt_getopt(so, sopt);
3241 			break;
3242 
3243 		case SO_LINGER:
3244 			SOCK_LOCK(so);
3245 			l.l_onoff = so->so_options & SO_LINGER;
3246 			l.l_linger = so->so_linger;
3247 			SOCK_UNLOCK(so);
3248 			error = sooptcopyout(sopt, &l, sizeof l);
3249 			break;
3250 
3251 		case SO_USELOOPBACK:
3252 		case SO_DONTROUTE:
3253 		case SO_DEBUG:
3254 		case SO_KEEPALIVE:
3255 		case SO_REUSEADDR:
3256 		case SO_REUSEPORT:
3257 		case SO_REUSEPORT_LB:
3258 		case SO_BROADCAST:
3259 		case SO_OOBINLINE:
3260 		case SO_ACCEPTCONN:
3261 		case SO_TIMESTAMP:
3262 		case SO_BINTIME:
3263 		case SO_NOSIGPIPE:
3264 		case SO_NO_DDP:
3265 		case SO_NO_OFFLOAD:
3266 			optval = so->so_options & sopt->sopt_name;
3267 integer:
3268 			error = sooptcopyout(sopt, &optval, sizeof optval);
3269 			break;
3270 
3271 		case SO_DOMAIN:
3272 			optval = so->so_proto->pr_domain->dom_family;
3273 			goto integer;
3274 
3275 		case SO_TYPE:
3276 			optval = so->so_type;
3277 			goto integer;
3278 
3279 		case SO_PROTOCOL:
3280 			optval = so->so_proto->pr_protocol;
3281 			goto integer;
3282 
3283 		case SO_ERROR:
3284 			SOCK_LOCK(so);
3285 			optval = so->so_error;
3286 			so->so_error = 0;
3287 			SOCK_UNLOCK(so);
3288 			goto integer;
3289 
3290 		case SO_SNDBUF:
3291 			optval = SOLISTENING(so) ? so->sol_sbsnd_hiwat :
3292 			    so->so_snd.sb_hiwat;
3293 			goto integer;
3294 
3295 		case SO_RCVBUF:
3296 			optval = SOLISTENING(so) ? so->sol_sbrcv_hiwat :
3297 			    so->so_rcv.sb_hiwat;
3298 			goto integer;
3299 
3300 		case SO_SNDLOWAT:
3301 			optval = SOLISTENING(so) ? so->sol_sbsnd_lowat :
3302 			    so->so_snd.sb_lowat;
3303 			goto integer;
3304 
3305 		case SO_RCVLOWAT:
3306 			optval = SOLISTENING(so) ? so->sol_sbrcv_lowat :
3307 			    so->so_rcv.sb_lowat;
3308 			goto integer;
3309 
3310 		case SO_SNDTIMEO:
3311 		case SO_RCVTIMEO:
3312 			tv = sbttotv(sopt->sopt_name == SO_SNDTIMEO ?
3313 			    so->so_snd.sb_timeo : so->so_rcv.sb_timeo);
3314 #ifdef COMPAT_FREEBSD32
3315 			if (SV_CURPROC_FLAG(SV_ILP32)) {
3316 				struct timeval32 tv32;
3317 
3318 				CP(tv, tv32, tv_sec);
3319 				CP(tv, tv32, tv_usec);
3320 				error = sooptcopyout(sopt, &tv32, sizeof tv32);
3321 			} else
3322 #endif
3323 				error = sooptcopyout(sopt, &tv, sizeof tv);
3324 			break;
3325 
3326 		case SO_LABEL:
3327 #ifdef MAC
3328 			error = sooptcopyin(sopt, &extmac, sizeof(extmac),
3329 			    sizeof(extmac));
3330 			if (error)
3331 				goto bad;
3332 			error = mac_getsockopt_label(sopt->sopt_td->td_ucred,
3333 			    so, &extmac);
3334 			if (error)
3335 				goto bad;
3336 			error = sooptcopyout(sopt, &extmac, sizeof extmac);
3337 #else
3338 			error = EOPNOTSUPP;
3339 #endif
3340 			break;
3341 
3342 		case SO_PEERLABEL:
3343 #ifdef MAC
3344 			error = sooptcopyin(sopt, &extmac, sizeof(extmac),
3345 			    sizeof(extmac));
3346 			if (error)
3347 				goto bad;
3348 			error = mac_getsockopt_peerlabel(
3349 			    sopt->sopt_td->td_ucred, so, &extmac);
3350 			if (error)
3351 				goto bad;
3352 			error = sooptcopyout(sopt, &extmac, sizeof extmac);
3353 #else
3354 			error = EOPNOTSUPP;
3355 #endif
3356 			break;
3357 
3358 		case SO_LISTENQLIMIT:
3359 			optval = SOLISTENING(so) ? so->sol_qlimit : 0;
3360 			goto integer;
3361 
3362 		case SO_LISTENQLEN:
3363 			optval = SOLISTENING(so) ? so->sol_qlen : 0;
3364 			goto integer;
3365 
3366 		case SO_LISTENINCQLEN:
3367 			optval = SOLISTENING(so) ? so->sol_incqlen : 0;
3368 			goto integer;
3369 
3370 		case SO_TS_CLOCK:
3371 			optval = so->so_ts_clock;
3372 			goto integer;
3373 
3374 		case SO_MAX_PACING_RATE:
3375 			optval = so->so_max_pacing_rate;
3376 			goto integer;
3377 
3378 		default:
3379 			if (V_socket_hhh[HHOOK_SOCKET_OPT]->hhh_nhooks > 0)
3380 				error = hhook_run_socket(so, sopt,
3381 				    HHOOK_SOCKET_OPT);
3382 			else
3383 				error = ENOPROTOOPT;
3384 			break;
3385 		}
3386 	}
3387 #ifdef MAC
3388 bad:
3389 #endif
3390 	CURVNET_RESTORE();
3391 	return (error);
3392 }
3393 
3394 int
3395 soopt_getm(struct sockopt *sopt, struct mbuf **mp)
3396 {
3397 	struct mbuf *m, *m_prev;
3398 	int sopt_size = sopt->sopt_valsize;
3399 
3400 	MGET(m, sopt->sopt_td ? M_WAITOK : M_NOWAIT, MT_DATA);
3401 	if (m == NULL)
3402 		return ENOBUFS;
3403 	if (sopt_size > MLEN) {
3404 		MCLGET(m, sopt->sopt_td ? M_WAITOK : M_NOWAIT);
3405 		if ((m->m_flags & M_EXT) == 0) {
3406 			m_free(m);
3407 			return ENOBUFS;
3408 		}
3409 		m->m_len = min(MCLBYTES, sopt_size);
3410 	} else {
3411 		m->m_len = min(MLEN, sopt_size);
3412 	}
3413 	sopt_size -= m->m_len;
3414 	*mp = m;
3415 	m_prev = m;
3416 
3417 	while (sopt_size) {
3418 		MGET(m, sopt->sopt_td ? M_WAITOK : M_NOWAIT, MT_DATA);
3419 		if (m == NULL) {
3420 			m_freem(*mp);
3421 			return ENOBUFS;
3422 		}
3423 		if (sopt_size > MLEN) {
3424 			MCLGET(m, sopt->sopt_td != NULL ? M_WAITOK :
3425 			    M_NOWAIT);
3426 			if ((m->m_flags & M_EXT) == 0) {
3427 				m_freem(m);
3428 				m_freem(*mp);
3429 				return ENOBUFS;
3430 			}
3431 			m->m_len = min(MCLBYTES, sopt_size);
3432 		} else {
3433 			m->m_len = min(MLEN, sopt_size);
3434 		}
3435 		sopt_size -= m->m_len;
3436 		m_prev->m_next = m;
3437 		m_prev = m;
3438 	}
3439 	return (0);
3440 }
3441 
3442 int
3443 soopt_mcopyin(struct sockopt *sopt, struct mbuf *m)
3444 {
3445 	struct mbuf *m0 = m;
3446 
3447 	if (sopt->sopt_val == NULL)
3448 		return (0);
3449 	while (m != NULL && sopt->sopt_valsize >= m->m_len) {
3450 		if (sopt->sopt_td != NULL) {
3451 			int error;
3452 
3453 			error = copyin(sopt->sopt_val, mtod(m, char *),
3454 			    m->m_len);
3455 			if (error != 0) {
3456 				m_freem(m0);
3457 				return(error);
3458 			}
3459 		} else
3460 			bcopy(sopt->sopt_val, mtod(m, char *), m->m_len);
3461 		sopt->sopt_valsize -= m->m_len;
3462 		sopt->sopt_val = (char *)sopt->sopt_val + m->m_len;
3463 		m = m->m_next;
3464 	}
3465 	if (m != NULL) /* should be allocated enoughly at ip6_sooptmcopyin() */
3466 		panic("ip6_sooptmcopyin");
3467 	return (0);
3468 }
3469 
3470 int
3471 soopt_mcopyout(struct sockopt *sopt, struct mbuf *m)
3472 {
3473 	struct mbuf *m0 = m;
3474 	size_t valsize = 0;
3475 
3476 	if (sopt->sopt_val == NULL)
3477 		return (0);
3478 	while (m != NULL && sopt->sopt_valsize >= m->m_len) {
3479 		if (sopt->sopt_td != NULL) {
3480 			int error;
3481 
3482 			error = copyout(mtod(m, char *), sopt->sopt_val,
3483 			    m->m_len);
3484 			if (error != 0) {
3485 				m_freem(m0);
3486 				return(error);
3487 			}
3488 		} else
3489 			bcopy(mtod(m, char *), sopt->sopt_val, m->m_len);
3490 		sopt->sopt_valsize -= m->m_len;
3491 		sopt->sopt_val = (char *)sopt->sopt_val + m->m_len;
3492 		valsize += m->m_len;
3493 		m = m->m_next;
3494 	}
3495 	if (m != NULL) {
3496 		/* enough soopt buffer should be given from user-land */
3497 		m_freem(m0);
3498 		return(EINVAL);
3499 	}
3500 	sopt->sopt_valsize = valsize;
3501 	return (0);
3502 }
3503 
3504 /*
3505  * sohasoutofband(): protocol notifies socket layer of the arrival of new
3506  * out-of-band data, which will then notify socket consumers.
3507  */
3508 void
3509 sohasoutofband(struct socket *so)
3510 {
3511 
3512 	if (so->so_sigio != NULL)
3513 		pgsigio(&so->so_sigio, SIGURG, 0);
3514 	selwakeuppri(&so->so_rdsel, PSOCK);
3515 }
3516 
3517 int
3518 sopoll(struct socket *so, int events, struct ucred *active_cred,
3519     struct thread *td)
3520 {
3521 
3522 	/*
3523 	 * We do not need to set or assert curvnet as long as everyone uses
3524 	 * sopoll_generic().
3525 	 */
3526 	return (so->so_proto->pr_usrreqs->pru_sopoll(so, events, active_cred,
3527 	    td));
3528 }
3529 
3530 int
3531 sopoll_generic(struct socket *so, int events, struct ucred *active_cred,
3532     struct thread *td)
3533 {
3534 	int revents;
3535 
3536 	SOCK_LOCK(so);
3537 	if (SOLISTENING(so)) {
3538 		if (!(events & (POLLIN | POLLRDNORM)))
3539 			revents = 0;
3540 		else if (!TAILQ_EMPTY(&so->sol_comp))
3541 			revents = events & (POLLIN | POLLRDNORM);
3542 		else if ((events & POLLINIGNEOF) == 0 && so->so_error)
3543 			revents = (events & (POLLIN | POLLRDNORM)) | POLLHUP;
3544 		else {
3545 			selrecord(td, &so->so_rdsel);
3546 			revents = 0;
3547 		}
3548 	} else {
3549 		revents = 0;
3550 		SOCKBUF_LOCK(&so->so_snd);
3551 		SOCKBUF_LOCK(&so->so_rcv);
3552 		if (events & (POLLIN | POLLRDNORM))
3553 			if (soreadabledata(so))
3554 				revents |= events & (POLLIN | POLLRDNORM);
3555 		if (events & (POLLOUT | POLLWRNORM))
3556 			if (sowriteable(so))
3557 				revents |= events & (POLLOUT | POLLWRNORM);
3558 		if (events & (POLLPRI | POLLRDBAND))
3559 			if (so->so_oobmark ||
3560 			    (so->so_rcv.sb_state & SBS_RCVATMARK))
3561 				revents |= events & (POLLPRI | POLLRDBAND);
3562 		if ((events & POLLINIGNEOF) == 0) {
3563 			if (so->so_rcv.sb_state & SBS_CANTRCVMORE) {
3564 				revents |= events & (POLLIN | POLLRDNORM);
3565 				if (so->so_snd.sb_state & SBS_CANTSENDMORE)
3566 					revents |= POLLHUP;
3567 			}
3568 		}
3569 		if (revents == 0) {
3570 			if (events &
3571 			    (POLLIN | POLLPRI | POLLRDNORM | POLLRDBAND)) {
3572 				selrecord(td, &so->so_rdsel);
3573 				so->so_rcv.sb_flags |= SB_SEL;
3574 			}
3575 			if (events & (POLLOUT | POLLWRNORM)) {
3576 				selrecord(td, &so->so_wrsel);
3577 				so->so_snd.sb_flags |= SB_SEL;
3578 			}
3579 		}
3580 		SOCKBUF_UNLOCK(&so->so_rcv);
3581 		SOCKBUF_UNLOCK(&so->so_snd);
3582 	}
3583 	SOCK_UNLOCK(so);
3584 	return (revents);
3585 }
3586 
3587 int
3588 soo_kqfilter(struct file *fp, struct knote *kn)
3589 {
3590 	struct socket *so = kn->kn_fp->f_data;
3591 	struct sockbuf *sb;
3592 	struct knlist *knl;
3593 
3594 	switch (kn->kn_filter) {
3595 	case EVFILT_READ:
3596 		kn->kn_fop = &soread_filtops;
3597 		knl = &so->so_rdsel.si_note;
3598 		sb = &so->so_rcv;
3599 		break;
3600 	case EVFILT_WRITE:
3601 		kn->kn_fop = &sowrite_filtops;
3602 		knl = &so->so_wrsel.si_note;
3603 		sb = &so->so_snd;
3604 		break;
3605 	case EVFILT_EMPTY:
3606 		kn->kn_fop = &soempty_filtops;
3607 		knl = &so->so_wrsel.si_note;
3608 		sb = &so->so_snd;
3609 		break;
3610 	default:
3611 		return (EINVAL);
3612 	}
3613 
3614 	SOCK_LOCK(so);
3615 	if (SOLISTENING(so)) {
3616 		knlist_add(knl, kn, 1);
3617 	} else {
3618 		SOCKBUF_LOCK(sb);
3619 		knlist_add(knl, kn, 1);
3620 		sb->sb_flags |= SB_KNOTE;
3621 		SOCKBUF_UNLOCK(sb);
3622 	}
3623 	SOCK_UNLOCK(so);
3624 	return (0);
3625 }
3626 
3627 /*
3628  * Some routines that return EOPNOTSUPP for entry points that are not
3629  * supported by a protocol.  Fill in as needed.
3630  */
3631 int
3632 pru_accept_notsupp(struct socket *so, struct sockaddr **nam)
3633 {
3634 
3635 	return EOPNOTSUPP;
3636 }
3637 
3638 int
3639 pru_aio_queue_notsupp(struct socket *so, struct kaiocb *job)
3640 {
3641 
3642 	return EOPNOTSUPP;
3643 }
3644 
3645 int
3646 pru_attach_notsupp(struct socket *so, int proto, struct thread *td)
3647 {
3648 
3649 	return EOPNOTSUPP;
3650 }
3651 
3652 int
3653 pru_bind_notsupp(struct socket *so, struct sockaddr *nam, struct thread *td)
3654 {
3655 
3656 	return EOPNOTSUPP;
3657 }
3658 
3659 int
3660 pru_bindat_notsupp(int fd, struct socket *so, struct sockaddr *nam,
3661     struct thread *td)
3662 {
3663 
3664 	return EOPNOTSUPP;
3665 }
3666 
3667 int
3668 pru_connect_notsupp(struct socket *so, struct sockaddr *nam, struct thread *td)
3669 {
3670 
3671 	return EOPNOTSUPP;
3672 }
3673 
3674 int
3675 pru_connectat_notsupp(int fd, struct socket *so, struct sockaddr *nam,
3676     struct thread *td)
3677 {
3678 
3679 	return EOPNOTSUPP;
3680 }
3681 
3682 int
3683 pru_connect2_notsupp(struct socket *so1, struct socket *so2)
3684 {
3685 
3686 	return EOPNOTSUPP;
3687 }
3688 
3689 int
3690 pru_control_notsupp(struct socket *so, u_long cmd, caddr_t data,
3691     struct ifnet *ifp, struct thread *td)
3692 {
3693 
3694 	return EOPNOTSUPP;
3695 }
3696 
3697 int
3698 pru_disconnect_notsupp(struct socket *so)
3699 {
3700 
3701 	return EOPNOTSUPP;
3702 }
3703 
3704 int
3705 pru_listen_notsupp(struct socket *so, int backlog, struct thread *td)
3706 {
3707 
3708 	return EOPNOTSUPP;
3709 }
3710 
3711 int
3712 pru_peeraddr_notsupp(struct socket *so, struct sockaddr **nam)
3713 {
3714 
3715 	return EOPNOTSUPP;
3716 }
3717 
3718 int
3719 pru_rcvd_notsupp(struct socket *so, int flags)
3720 {
3721 
3722 	return EOPNOTSUPP;
3723 }
3724 
3725 int
3726 pru_rcvoob_notsupp(struct socket *so, struct mbuf *m, int flags)
3727 {
3728 
3729 	return EOPNOTSUPP;
3730 }
3731 
3732 int
3733 pru_send_notsupp(struct socket *so, int flags, struct mbuf *m,
3734     struct sockaddr *addr, struct mbuf *control, struct thread *td)
3735 {
3736 
3737 	return EOPNOTSUPP;
3738 }
3739 
3740 int
3741 pru_ready_notsupp(struct socket *so, struct mbuf *m, int count)
3742 {
3743 
3744 	return (EOPNOTSUPP);
3745 }
3746 
3747 /*
3748  * This isn't really a ``null'' operation, but it's the default one and
3749  * doesn't do anything destructive.
3750  */
3751 int
3752 pru_sense_null(struct socket *so, struct stat *sb)
3753 {
3754 
3755 	sb->st_blksize = so->so_snd.sb_hiwat;
3756 	return 0;
3757 }
3758 
3759 int
3760 pru_shutdown_notsupp(struct socket *so)
3761 {
3762 
3763 	return EOPNOTSUPP;
3764 }
3765 
3766 int
3767 pru_sockaddr_notsupp(struct socket *so, struct sockaddr **nam)
3768 {
3769 
3770 	return EOPNOTSUPP;
3771 }
3772 
3773 int
3774 pru_sosend_notsupp(struct socket *so, struct sockaddr *addr, struct uio *uio,
3775     struct mbuf *top, struct mbuf *control, int flags, struct thread *td)
3776 {
3777 
3778 	return EOPNOTSUPP;
3779 }
3780 
3781 int
3782 pru_soreceive_notsupp(struct socket *so, struct sockaddr **paddr,
3783     struct uio *uio, struct mbuf **mp0, struct mbuf **controlp, int *flagsp)
3784 {
3785 
3786 	return EOPNOTSUPP;
3787 }
3788 
3789 int
3790 pru_sopoll_notsupp(struct socket *so, int events, struct ucred *cred,
3791     struct thread *td)
3792 {
3793 
3794 	return EOPNOTSUPP;
3795 }
3796 
3797 static void
3798 filt_sordetach(struct knote *kn)
3799 {
3800 	struct socket *so = kn->kn_fp->f_data;
3801 
3802 	so_rdknl_lock(so);
3803 	knlist_remove(&so->so_rdsel.si_note, kn, 1);
3804 	if (!SOLISTENING(so) && knlist_empty(&so->so_rdsel.si_note))
3805 		so->so_rcv.sb_flags &= ~SB_KNOTE;
3806 	so_rdknl_unlock(so);
3807 }
3808 
3809 /*ARGSUSED*/
3810 static int
3811 filt_soread(struct knote *kn, long hint)
3812 {
3813 	struct socket *so;
3814 
3815 	so = kn->kn_fp->f_data;
3816 
3817 	if (SOLISTENING(so)) {
3818 		SOCK_LOCK_ASSERT(so);
3819 		kn->kn_data = so->sol_qlen;
3820 		if (so->so_error) {
3821 			kn->kn_flags |= EV_EOF;
3822 			kn->kn_fflags = so->so_error;
3823 			return (1);
3824 		}
3825 		return (!TAILQ_EMPTY(&so->sol_comp));
3826 	}
3827 
3828 	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
3829 
3830 	kn->kn_data = sbavail(&so->so_rcv) - so->so_rcv.sb_ctl;
3831 	if (so->so_rcv.sb_state & SBS_CANTRCVMORE) {
3832 		kn->kn_flags |= EV_EOF;
3833 		kn->kn_fflags = so->so_error;
3834 		return (1);
3835 	} else if (so->so_error)	/* temporary udp error */
3836 		return (1);
3837 
3838 	if (kn->kn_sfflags & NOTE_LOWAT) {
3839 		if (kn->kn_data >= kn->kn_sdata)
3840 			return (1);
3841 	} else if (sbavail(&so->so_rcv) >= so->so_rcv.sb_lowat)
3842 		return (1);
3843 
3844 	/* This hook returning non-zero indicates an event, not error */
3845 	return (hhook_run_socket(so, NULL, HHOOK_FILT_SOREAD));
3846 }
3847 
3848 static void
3849 filt_sowdetach(struct knote *kn)
3850 {
3851 	struct socket *so = kn->kn_fp->f_data;
3852 
3853 	so_wrknl_lock(so);
3854 	knlist_remove(&so->so_wrsel.si_note, kn, 1);
3855 	if (!SOLISTENING(so) && knlist_empty(&so->so_wrsel.si_note))
3856 		so->so_snd.sb_flags &= ~SB_KNOTE;
3857 	so_wrknl_unlock(so);
3858 }
3859 
3860 /*ARGSUSED*/
3861 static int
3862 filt_sowrite(struct knote *kn, long hint)
3863 {
3864 	struct socket *so;
3865 
3866 	so = kn->kn_fp->f_data;
3867 
3868 	if (SOLISTENING(so))
3869 		return (0);
3870 
3871 	SOCKBUF_LOCK_ASSERT(&so->so_snd);
3872 	kn->kn_data = sbspace(&so->so_snd);
3873 
3874 	hhook_run_socket(so, kn, HHOOK_FILT_SOWRITE);
3875 
3876 	if (so->so_snd.sb_state & SBS_CANTSENDMORE) {
3877 		kn->kn_flags |= EV_EOF;
3878 		kn->kn_fflags = so->so_error;
3879 		return (1);
3880 	} else if (so->so_error)	/* temporary udp error */
3881 		return (1);
3882 	else if (((so->so_state & SS_ISCONNECTED) == 0) &&
3883 	    (so->so_proto->pr_flags & PR_CONNREQUIRED))
3884 		return (0);
3885 	else if (kn->kn_sfflags & NOTE_LOWAT)
3886 		return (kn->kn_data >= kn->kn_sdata);
3887 	else
3888 		return (kn->kn_data >= so->so_snd.sb_lowat);
3889 }
3890 
3891 static int
3892 filt_soempty(struct knote *kn, long hint)
3893 {
3894 	struct socket *so;
3895 
3896 	so = kn->kn_fp->f_data;
3897 
3898 	if (SOLISTENING(so))
3899 		return (1);
3900 
3901 	SOCKBUF_LOCK_ASSERT(&so->so_snd);
3902 	kn->kn_data = sbused(&so->so_snd);
3903 
3904 	if (kn->kn_data == 0)
3905 		return (1);
3906 	else
3907 		return (0);
3908 }
3909 
3910 int
3911 socheckuid(struct socket *so, uid_t uid)
3912 {
3913 
3914 	if (so == NULL)
3915 		return (EPERM);
3916 	if (so->so_cred->cr_uid != uid)
3917 		return (EPERM);
3918 	return (0);
3919 }
3920 
3921 /*
3922  * These functions are used by protocols to notify the socket layer (and its
3923  * consumers) of state changes in the sockets driven by protocol-side events.
3924  */
3925 
3926 /*
3927  * Procedures to manipulate state flags of socket and do appropriate wakeups.
3928  *
3929  * Normal sequence from the active (originating) side is that
3930  * soisconnecting() is called during processing of connect() call, resulting
3931  * in an eventual call to soisconnected() if/when the connection is
3932  * established.  When the connection is torn down soisdisconnecting() is
3933  * called during processing of disconnect() call, and soisdisconnected() is
3934  * called when the connection to the peer is totally severed.  The semantics
3935  * of these routines are such that connectionless protocols can call
3936  * soisconnected() and soisdisconnected() only, bypassing the in-progress
3937  * calls when setting up a ``connection'' takes no time.
3938  *
3939  * From the passive side, a socket is created with two queues of sockets:
3940  * so_incomp for connections in progress and so_comp for connections already
3941  * made and awaiting user acceptance.  As a protocol is preparing incoming
3942  * connections, it creates a socket structure queued on so_incomp by calling
3943  * sonewconn().  When the connection is established, soisconnected() is
3944  * called, and transfers the socket structure to so_comp, making it available
3945  * to accept().
3946  *
3947  * If a socket is closed with sockets on either so_incomp or so_comp, these
3948  * sockets are dropped.
3949  *
3950  * If higher-level protocols are implemented in the kernel, the wakeups done
3951  * here will sometimes cause software-interrupt process scheduling.
3952  */
3953 void
3954 soisconnecting(struct socket *so)
3955 {
3956 
3957 	SOCK_LOCK(so);
3958 	so->so_state &= ~(SS_ISCONNECTED|SS_ISDISCONNECTING);
3959 	so->so_state |= SS_ISCONNECTING;
3960 	SOCK_UNLOCK(so);
3961 }
3962 
3963 void
3964 soisconnected(struct socket *so)
3965 {
3966 
3967 	SOCK_LOCK(so);
3968 	so->so_state &= ~(SS_ISCONNECTING|SS_ISDISCONNECTING|SS_ISCONFIRMING);
3969 	so->so_state |= SS_ISCONNECTED;
3970 
3971 	if (so->so_qstate == SQ_INCOMP) {
3972 		struct socket *head = so->so_listen;
3973 		int ret;
3974 
3975 		KASSERT(head, ("%s: so %p on incomp of NULL", __func__, so));
3976 		/*
3977 		 * Promoting a socket from incomplete queue to complete, we
3978 		 * need to go through reverse order of locking.  We first do
3979 		 * trylock, and if that doesn't succeed, we go the hard way
3980 		 * leaving a reference and rechecking consistency after proper
3981 		 * locking.
3982 		 */
3983 		if (__predict_false(SOLISTEN_TRYLOCK(head) == 0)) {
3984 			soref(head);
3985 			SOCK_UNLOCK(so);
3986 			SOLISTEN_LOCK(head);
3987 			SOCK_LOCK(so);
3988 			if (__predict_false(head != so->so_listen)) {
3989 				/*
3990 				 * The socket went off the listen queue,
3991 				 * should be lost race to close(2) of sol.
3992 				 * The socket is about to soabort().
3993 				 */
3994 				SOCK_UNLOCK(so);
3995 				sorele(head);
3996 				return;
3997 			}
3998 			/* Not the last one, as so holds a ref. */
3999 			refcount_release(&head->so_count);
4000 		}
4001 again:
4002 		if ((so->so_options & SO_ACCEPTFILTER) == 0) {
4003 			TAILQ_REMOVE(&head->sol_incomp, so, so_list);
4004 			head->sol_incqlen--;
4005 			TAILQ_INSERT_TAIL(&head->sol_comp, so, so_list);
4006 			head->sol_qlen++;
4007 			so->so_qstate = SQ_COMP;
4008 			SOCK_UNLOCK(so);
4009 			solisten_wakeup(head);	/* unlocks */
4010 		} else {
4011 			SOCKBUF_LOCK(&so->so_rcv);
4012 			soupcall_set(so, SO_RCV,
4013 			    head->sol_accept_filter->accf_callback,
4014 			    head->sol_accept_filter_arg);
4015 			so->so_options &= ~SO_ACCEPTFILTER;
4016 			ret = head->sol_accept_filter->accf_callback(so,
4017 			    head->sol_accept_filter_arg, M_NOWAIT);
4018 			if (ret == SU_ISCONNECTED) {
4019 				soupcall_clear(so, SO_RCV);
4020 				SOCKBUF_UNLOCK(&so->so_rcv);
4021 				goto again;
4022 			}
4023 			SOCKBUF_UNLOCK(&so->so_rcv);
4024 			SOCK_UNLOCK(so);
4025 			SOLISTEN_UNLOCK(head);
4026 		}
4027 		return;
4028 	}
4029 	SOCK_UNLOCK(so);
4030 	wakeup(&so->so_timeo);
4031 	sorwakeup(so);
4032 	sowwakeup(so);
4033 }
4034 
4035 void
4036 soisdisconnecting(struct socket *so)
4037 {
4038 
4039 	SOCK_LOCK(so);
4040 	so->so_state &= ~SS_ISCONNECTING;
4041 	so->so_state |= SS_ISDISCONNECTING;
4042 
4043 	if (!SOLISTENING(so)) {
4044 		SOCKBUF_LOCK(&so->so_rcv);
4045 		socantrcvmore_locked(so);
4046 		SOCKBUF_LOCK(&so->so_snd);
4047 		socantsendmore_locked(so);
4048 	}
4049 	SOCK_UNLOCK(so);
4050 	wakeup(&so->so_timeo);
4051 }
4052 
4053 void
4054 soisdisconnected(struct socket *so)
4055 {
4056 
4057 	SOCK_LOCK(so);
4058 
4059 	/*
4060 	 * There is at least one reader of so_state that does not
4061 	 * acquire socket lock, namely soreceive_generic().  Ensure
4062 	 * that it never sees all flags that track connection status
4063 	 * cleared, by ordering the update with a barrier semantic of
4064 	 * our release thread fence.
4065 	 */
4066 	so->so_state |= SS_ISDISCONNECTED;
4067 	atomic_thread_fence_rel();
4068 	so->so_state &= ~(SS_ISCONNECTING|SS_ISCONNECTED|SS_ISDISCONNECTING);
4069 
4070 	if (!SOLISTENING(so)) {
4071 		SOCK_UNLOCK(so);
4072 		SOCKBUF_LOCK(&so->so_rcv);
4073 		socantrcvmore_locked(so);
4074 		SOCKBUF_LOCK(&so->so_snd);
4075 		sbdrop_locked(&so->so_snd, sbused(&so->so_snd));
4076 		socantsendmore_locked(so);
4077 	} else
4078 		SOCK_UNLOCK(so);
4079 	wakeup(&so->so_timeo);
4080 }
4081 
4082 /*
4083  * Make a copy of a sockaddr in a malloced buffer of type M_SONAME.
4084  */
4085 struct sockaddr *
4086 sodupsockaddr(const struct sockaddr *sa, int mflags)
4087 {
4088 	struct sockaddr *sa2;
4089 
4090 	sa2 = malloc(sa->sa_len, M_SONAME, mflags);
4091 	if (sa2)
4092 		bcopy(sa, sa2, sa->sa_len);
4093 	return sa2;
4094 }
4095 
4096 /*
4097  * Register per-socket destructor.
4098  */
4099 void
4100 sodtor_set(struct socket *so, so_dtor_t *func)
4101 {
4102 
4103 	SOCK_LOCK_ASSERT(so);
4104 	so->so_dtor = func;
4105 }
4106 
4107 /*
4108  * Register per-socket buffer upcalls.
4109  */
4110 void
4111 soupcall_set(struct socket *so, int which, so_upcall_t func, void *arg)
4112 {
4113 	struct sockbuf *sb;
4114 
4115 	KASSERT(!SOLISTENING(so), ("%s: so %p listening", __func__, so));
4116 
4117 	switch (which) {
4118 	case SO_RCV:
4119 		sb = &so->so_rcv;
4120 		break;
4121 	case SO_SND:
4122 		sb = &so->so_snd;
4123 		break;
4124 	default:
4125 		panic("soupcall_set: bad which");
4126 	}
4127 	SOCKBUF_LOCK_ASSERT(sb);
4128 	sb->sb_upcall = func;
4129 	sb->sb_upcallarg = arg;
4130 	sb->sb_flags |= SB_UPCALL;
4131 }
4132 
4133 void
4134 soupcall_clear(struct socket *so, int which)
4135 {
4136 	struct sockbuf *sb;
4137 
4138 	KASSERT(!SOLISTENING(so), ("%s: so %p listening", __func__, so));
4139 
4140 	switch (which) {
4141 	case SO_RCV:
4142 		sb = &so->so_rcv;
4143 		break;
4144 	case SO_SND:
4145 		sb = &so->so_snd;
4146 		break;
4147 	default:
4148 		panic("soupcall_clear: bad which");
4149 	}
4150 	SOCKBUF_LOCK_ASSERT(sb);
4151 	KASSERT(sb->sb_upcall != NULL,
4152 	    ("%s: so %p no upcall to clear", __func__, so));
4153 	sb->sb_upcall = NULL;
4154 	sb->sb_upcallarg = NULL;
4155 	sb->sb_flags &= ~SB_UPCALL;
4156 }
4157 
4158 void
4159 solisten_upcall_set(struct socket *so, so_upcall_t func, void *arg)
4160 {
4161 
4162 	SOLISTEN_LOCK_ASSERT(so);
4163 	so->sol_upcall = func;
4164 	so->sol_upcallarg = arg;
4165 }
4166 
4167 static void
4168 so_rdknl_lock(void *arg)
4169 {
4170 	struct socket *so = arg;
4171 
4172 	if (SOLISTENING(so))
4173 		SOCK_LOCK(so);
4174 	else
4175 		SOCKBUF_LOCK(&so->so_rcv);
4176 }
4177 
4178 static void
4179 so_rdknl_unlock(void *arg)
4180 {
4181 	struct socket *so = arg;
4182 
4183 	if (SOLISTENING(so))
4184 		SOCK_UNLOCK(so);
4185 	else
4186 		SOCKBUF_UNLOCK(&so->so_rcv);
4187 }
4188 
4189 static void
4190 so_rdknl_assert_lock(void *arg, int what)
4191 {
4192 	struct socket *so = arg;
4193 
4194 	if (what == LA_LOCKED) {
4195 		if (SOLISTENING(so))
4196 			SOCK_LOCK_ASSERT(so);
4197 		else
4198 			SOCKBUF_LOCK_ASSERT(&so->so_rcv);
4199 	} else {
4200 		if (SOLISTENING(so))
4201 			SOCK_UNLOCK_ASSERT(so);
4202 		else
4203 			SOCKBUF_UNLOCK_ASSERT(&so->so_rcv);
4204 	}
4205 }
4206 
4207 static void
4208 so_wrknl_lock(void *arg)
4209 {
4210 	struct socket *so = arg;
4211 
4212 	if (SOLISTENING(so))
4213 		SOCK_LOCK(so);
4214 	else
4215 		SOCKBUF_LOCK(&so->so_snd);
4216 }
4217 
4218 static void
4219 so_wrknl_unlock(void *arg)
4220 {
4221 	struct socket *so = arg;
4222 
4223 	if (SOLISTENING(so))
4224 		SOCK_UNLOCK(so);
4225 	else
4226 		SOCKBUF_UNLOCK(&so->so_snd);
4227 }
4228 
4229 static void
4230 so_wrknl_assert_lock(void *arg, int what)
4231 {
4232 	struct socket *so = arg;
4233 
4234 	if (what == LA_LOCKED) {
4235 		if (SOLISTENING(so))
4236 			SOCK_LOCK_ASSERT(so);
4237 		else
4238 			SOCKBUF_LOCK_ASSERT(&so->so_snd);
4239 	} else {
4240 		if (SOLISTENING(so))
4241 			SOCK_UNLOCK_ASSERT(so);
4242 		else
4243 			SOCKBUF_UNLOCK_ASSERT(&so->so_snd);
4244 	}
4245 }
4246 
4247 /*
4248  * Create an external-format (``xsocket'') structure using the information in
4249  * the kernel-format socket structure pointed to by so.  This is done to
4250  * reduce the spew of irrelevant information over this interface, to isolate
4251  * user code from changes in the kernel structure, and potentially to provide
4252  * information-hiding if we decide that some of this information should be
4253  * hidden from users.
4254  */
4255 void
4256 sotoxsocket(struct socket *so, struct xsocket *xso)
4257 {
4258 
4259 	bzero(xso, sizeof(*xso));
4260 	xso->xso_len = sizeof *xso;
4261 	xso->xso_so = (uintptr_t)so;
4262 	xso->so_type = so->so_type;
4263 	xso->so_options = so->so_options;
4264 	xso->so_linger = so->so_linger;
4265 	xso->so_state = so->so_state;
4266 	xso->so_pcb = (uintptr_t)so->so_pcb;
4267 	xso->xso_protocol = so->so_proto->pr_protocol;
4268 	xso->xso_family = so->so_proto->pr_domain->dom_family;
4269 	xso->so_timeo = so->so_timeo;
4270 	xso->so_error = so->so_error;
4271 	xso->so_uid = so->so_cred->cr_uid;
4272 	xso->so_pgid = so->so_sigio ? so->so_sigio->sio_pgid : 0;
4273 	if (SOLISTENING(so)) {
4274 		xso->so_qlen = so->sol_qlen;
4275 		xso->so_incqlen = so->sol_incqlen;
4276 		xso->so_qlimit = so->sol_qlimit;
4277 		xso->so_oobmark = 0;
4278 	} else {
4279 		xso->so_state |= so->so_qstate;
4280 		xso->so_qlen = xso->so_incqlen = xso->so_qlimit = 0;
4281 		xso->so_oobmark = so->so_oobmark;
4282 		sbtoxsockbuf(&so->so_snd, &xso->so_snd);
4283 		sbtoxsockbuf(&so->so_rcv, &xso->so_rcv);
4284 	}
4285 }
4286 
4287 struct sockbuf *
4288 so_sockbuf_rcv(struct socket *so)
4289 {
4290 
4291 	return (&so->so_rcv);
4292 }
4293 
4294 struct sockbuf *
4295 so_sockbuf_snd(struct socket *so)
4296 {
4297 
4298 	return (&so->so_snd);
4299 }
4300 
4301 int
4302 so_state_get(const struct socket *so)
4303 {
4304 
4305 	return (so->so_state);
4306 }
4307 
4308 void
4309 so_state_set(struct socket *so, int val)
4310 {
4311 
4312 	so->so_state = val;
4313 }
4314 
4315 int
4316 so_options_get(const struct socket *so)
4317 {
4318 
4319 	return (so->so_options);
4320 }
4321 
4322 void
4323 so_options_set(struct socket *so, int val)
4324 {
4325 
4326 	so->so_options = val;
4327 }
4328 
4329 int
4330 so_error_get(const struct socket *so)
4331 {
4332 
4333 	return (so->so_error);
4334 }
4335 
4336 void
4337 so_error_set(struct socket *so, int val)
4338 {
4339 
4340 	so->so_error = val;
4341 }
4342 
4343 int
4344 so_linger_get(const struct socket *so)
4345 {
4346 
4347 	return (so->so_linger);
4348 }
4349 
4350 void
4351 so_linger_set(struct socket *so, int val)
4352 {
4353 
4354 	KASSERT(val >= 0 && val <= USHRT_MAX && val <= (INT_MAX / hz),
4355 	    ("%s: val %d out of range", __func__, val));
4356 
4357 	so->so_linger = val;
4358 }
4359 
4360 struct protosw *
4361 so_protosw_get(const struct socket *so)
4362 {
4363 
4364 	return (so->so_proto);
4365 }
4366 
4367 void
4368 so_protosw_set(struct socket *so, struct protosw *val)
4369 {
4370 
4371 	so->so_proto = val;
4372 }
4373 
4374 void
4375 so_sorwakeup(struct socket *so)
4376 {
4377 
4378 	sorwakeup(so);
4379 }
4380 
4381 void
4382 so_sowwakeup(struct socket *so)
4383 {
4384 
4385 	sowwakeup(so);
4386 }
4387 
4388 void
4389 so_sorwakeup_locked(struct socket *so)
4390 {
4391 
4392 	sorwakeup_locked(so);
4393 }
4394 
4395 void
4396 so_sowwakeup_locked(struct socket *so)
4397 {
4398 
4399 	sowwakeup_locked(so);
4400 }
4401 
4402 void
4403 so_lock(struct socket *so)
4404 {
4405 
4406 	SOCK_LOCK(so);
4407 }
4408 
4409 void
4410 so_unlock(struct socket *so)
4411 {
4412 
4413 	SOCK_UNLOCK(so);
4414 }
4415