xref: /openbsd-src/sys/kern/uipc_socket.c (revision 6a13ef69787db04ae501a22e92fa10865b44fd7c)
1 /*	$OpenBSD: uipc_socket.c,v 1.171 2016/12/29 12:12:43 mpi Exp $	*/
2 /*	$NetBSD: uipc_socket.c,v 1.21 1996/02/04 02:17:52 christos Exp $	*/
3 
4 /*
5  * Copyright (c) 1982, 1986, 1988, 1990, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  *
32  *	@(#)uipc_socket.c	8.3 (Berkeley) 4/15/94
33  */
34 
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/proc.h>
38 #include <sys/file.h>
39 #include <sys/filedesc.h>
40 #include <sys/malloc.h>
41 #include <sys/mbuf.h>
42 #include <sys/domain.h>
43 #include <sys/kernel.h>
44 #include <sys/event.h>
45 #include <sys/protosw.h>
46 #include <sys/socket.h>
47 #include <sys/unpcb.h>
48 #include <sys/socketvar.h>
49 #include <sys/signalvar.h>
50 #include <net/if.h>
51 #include <sys/pool.h>
52 
53 #ifdef DDB
54 #include <machine/db_machdep.h>
55 #endif
56 
57 void	sbsync(struct sockbuf *, struct mbuf *);
58 
59 int	sosplice(struct socket *, int, off_t, struct timeval *);
60 void	sounsplice(struct socket *, struct socket *, int);
61 void	soidle(void *);
62 void	sotask(void *);
63 int	somove(struct socket *, int);
64 
65 void	filt_sordetach(struct knote *kn);
66 int	filt_soread(struct knote *kn, long hint);
67 void	filt_sowdetach(struct knote *kn);
68 int	filt_sowrite(struct knote *kn, long hint);
69 int	filt_solisten(struct knote *kn, long hint);
70 
71 struct filterops solisten_filtops =
72 	{ 1, NULL, filt_sordetach, filt_solisten };
73 struct filterops soread_filtops =
74 	{ 1, NULL, filt_sordetach, filt_soread };
75 struct filterops sowrite_filtops =
76 	{ 1, NULL, filt_sowdetach, filt_sowrite };
77 
78 
79 #ifndef SOMINCONN
80 #define SOMINCONN 80
81 #endif /* SOMINCONN */
82 
83 int	somaxconn = SOMAXCONN;
84 int	sominconn = SOMINCONN;
85 
86 struct pool socket_pool;
87 #ifdef SOCKET_SPLICE
88 struct pool sosplice_pool;
89 struct taskq *sosplice_taskq;
90 #endif
91 
92 void
93 soinit(void)
94 {
95 	pool_init(&socket_pool, sizeof(struct socket), 0, IPL_SOFTNET, 0,
96 	    "sockpl", NULL);
97 #ifdef SOCKET_SPLICE
98 	pool_init(&sosplice_pool, sizeof(struct sosplice), 0, IPL_SOFTNET, 0,
99 	    "sosppl", NULL);
100 #endif
101 }
102 
103 /*
104  * Socket operation routines.
105  * These routines are called by the routines in
106  * sys_socket.c or from a system process, and
107  * implement the semantics of socket operations by
108  * switching out to the protocol specific routines.
109  */
110 int
111 socreate(int dom, struct socket **aso, int type, int proto)
112 {
113 	struct proc *p = curproc;		/* XXX */
114 	struct protosw *prp;
115 	struct socket *so;
116 	int error, s;
117 
118 	if (proto)
119 		prp = pffindproto(dom, proto, type);
120 	else
121 		prp = pffindtype(dom, type);
122 	if (prp == NULL || prp->pr_usrreq == 0)
123 		return (EPROTONOSUPPORT);
124 	if (prp->pr_type != type)
125 		return (EPROTOTYPE);
126 	NET_LOCK(s);
127 	so = pool_get(&socket_pool, PR_WAITOK | PR_ZERO);
128 	TAILQ_INIT(&so->so_q0);
129 	TAILQ_INIT(&so->so_q);
130 	so->so_type = type;
131 	if (suser(p, 0) == 0)
132 		so->so_state = SS_PRIV;
133 	so->so_ruid = p->p_ucred->cr_ruid;
134 	so->so_euid = p->p_ucred->cr_uid;
135 	so->so_rgid = p->p_ucred->cr_rgid;
136 	so->so_egid = p->p_ucred->cr_gid;
137 	so->so_cpid = p->p_p->ps_pid;
138 	so->so_proto = prp;
139 	error = (*prp->pr_usrreq)(so, PRU_ATTACH, NULL,
140 	    (struct mbuf *)(long)proto, NULL, p);
141 	if (error) {
142 		so->so_state |= SS_NOFDREF;
143 		sofree(so);
144 		NET_UNLOCK(s);
145 		return (error);
146 	}
147 	NET_UNLOCK(s);
148 	*aso = so;
149 	return (0);
150 }
151 
152 int
153 sobind(struct socket *so, struct mbuf *nam, struct proc *p)
154 {
155 	int s, error;
156 
157 	NET_LOCK(s);
158 	error = (*so->so_proto->pr_usrreq)(so, PRU_BIND, NULL, nam, NULL, p);
159 	NET_UNLOCK(s);
160 	return (error);
161 }
162 
163 int
164 solisten(struct socket *so, int backlog)
165 {
166 	int s, error;
167 
168 	if (so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING|SS_ISDISCONNECTING))
169 		return (EOPNOTSUPP);
170 #ifdef SOCKET_SPLICE
171 	if (isspliced(so) || issplicedback(so))
172 		return (EOPNOTSUPP);
173 #endif /* SOCKET_SPLICE */
174 	NET_LOCK(s);
175 	error = (*so->so_proto->pr_usrreq)(so, PRU_LISTEN, NULL, NULL, NULL,
176 	    curproc);
177 	if (error) {
178 		NET_UNLOCK(s);
179 		return (error);
180 	}
181 	if (TAILQ_FIRST(&so->so_q) == NULL)
182 		so->so_options |= SO_ACCEPTCONN;
183 	if (backlog < 0 || backlog > somaxconn)
184 		backlog = somaxconn;
185 	if (backlog < sominconn)
186 		backlog = sominconn;
187 	so->so_qlimit = backlog;
188 	NET_UNLOCK(s);
189 	return (0);
190 }
191 
192 void
193 sofree(struct socket *so)
194 {
195 	NET_ASSERT_LOCKED();
196 
197 	if (so->so_pcb || (so->so_state & SS_NOFDREF) == 0)
198 		return;
199 	if (so->so_head) {
200 		/*
201 		 * We must not decommission a socket that's on the accept(2)
202 		 * queue.  If we do, then accept(2) may hang after select(2)
203 		 * indicated that the listening socket was ready.
204 		 */
205 		if (!soqremque(so, 0))
206 			return;
207 	}
208 #ifdef SOCKET_SPLICE
209 	if (so->so_sp) {
210 		if (issplicedback(so))
211 			sounsplice(so->so_sp->ssp_soback, so,
212 			    so->so_sp->ssp_soback != so);
213 		if (isspliced(so))
214 			sounsplice(so, so->so_sp->ssp_socket, 0);
215 		pool_put(&sosplice_pool, so->so_sp);
216 		so->so_sp = NULL;
217 	}
218 #endif /* SOCKET_SPLICE */
219 	sbrelease(&so->so_snd);
220 	sorflush(so);
221 	pool_put(&socket_pool, so);
222 }
223 
224 /*
225  * Close a socket on last file table reference removal.
226  * Initiate disconnect if connected.
227  * Free socket when disconnect complete.
228  */
229 int
230 soclose(struct socket *so)
231 {
232 	struct socket *so2;
233 	int s, error = 0;
234 
235 	NET_LOCK(s);
236 	if (so->so_options & SO_ACCEPTCONN) {
237 		while ((so2 = TAILQ_FIRST(&so->so_q0)) != NULL) {
238 			(void) soqremque(so2, 0);
239 			(void) soabort(so2);
240 		}
241 		while ((so2 = TAILQ_FIRST(&so->so_q)) != NULL) {
242 			(void) soqremque(so2, 1);
243 			(void) soabort(so2);
244 		}
245 	}
246 	if (so->so_pcb == 0)
247 		goto discard;
248 	if (so->so_state & SS_ISCONNECTED) {
249 		if ((so->so_state & SS_ISDISCONNECTING) == 0) {
250 			error = sodisconnect(so);
251 			if (error)
252 				goto drop;
253 		}
254 		if (so->so_options & SO_LINGER) {
255 			if ((so->so_state & SS_ISDISCONNECTING) &&
256 			    (so->so_state & SS_NBIO))
257 				goto drop;
258 			while (so->so_state & SS_ISCONNECTED) {
259 				error = tsleep(&so->so_timeo,
260 				    PSOCK | PCATCH, "netcls",
261 				    so->so_linger * hz);
262 				if (error)
263 					break;
264 			}
265 		}
266 	}
267 drop:
268 	if (so->so_pcb) {
269 		int error2 = (*so->so_proto->pr_usrreq)(so, PRU_DETACH, NULL,
270 		    NULL, NULL, curproc);
271 		if (error == 0)
272 			error = error2;
273 	}
274 discard:
275 	if (so->so_state & SS_NOFDREF)
276 		panic("soclose NOFDREF: so %p, so_type %d", so, so->so_type);
277 	so->so_state |= SS_NOFDREF;
278 	sofree(so);
279 	NET_UNLOCK(s);
280 	return (error);
281 }
282 
283 int
284 soabort(struct socket *so)
285 {
286 	NET_ASSERT_LOCKED();
287 
288 	return (*so->so_proto->pr_usrreq)(so, PRU_ABORT, NULL, NULL, NULL,
289 	   curproc);
290 }
291 
292 int
293 soaccept(struct socket *so, struct mbuf *nam)
294 {
295 	int error = 0;
296 
297 	NET_ASSERT_LOCKED();
298 
299 	if ((so->so_state & SS_NOFDREF) == 0)
300 		panic("soaccept !NOFDREF: so %p, so_type %d", so, so->so_type);
301 	so->so_state &= ~SS_NOFDREF;
302 	if ((so->so_state & SS_ISDISCONNECTED) == 0 ||
303 	    (so->so_proto->pr_flags & PR_ABRTACPTDIS) == 0)
304 		error = (*so->so_proto->pr_usrreq)(so, PRU_ACCEPT, NULL,
305 		    nam, NULL, curproc);
306 	else
307 		error = ECONNABORTED;
308 	return (error);
309 }
310 
311 int
312 soconnect(struct socket *so, struct mbuf *nam)
313 {
314 	int s, error;
315 
316 	if (so->so_options & SO_ACCEPTCONN)
317 		return (EOPNOTSUPP);
318 	NET_LOCK(s);
319 	/*
320 	 * If protocol is connection-based, can only connect once.
321 	 * Otherwise, if connected, try to disconnect first.
322 	 * This allows user to disconnect by connecting to, e.g.,
323 	 * a null address.
324 	 */
325 	if (so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING) &&
326 	    ((so->so_proto->pr_flags & PR_CONNREQUIRED) ||
327 	    (error = sodisconnect(so))))
328 		error = EISCONN;
329 	else
330 		error = (*so->so_proto->pr_usrreq)(so, PRU_CONNECT,
331 		    NULL, nam, NULL, curproc);
332 	NET_UNLOCK(s);
333 	return (error);
334 }
335 
336 int
337 soconnect2(struct socket *so1, struct socket *so2)
338 {
339 	int s, error;
340 
341 	NET_LOCK(s);
342 	error = (*so1->so_proto->pr_usrreq)(so1, PRU_CONNECT2, NULL,
343 	    (struct mbuf *)so2, NULL, curproc);
344 	NET_UNLOCK(s);
345 	return (error);
346 }
347 
348 int
349 sodisconnect(struct socket *so)
350 {
351 	int error;
352 
353 	NET_ASSERT_LOCKED();
354 
355 	if ((so->so_state & SS_ISCONNECTED) == 0)
356 		return (ENOTCONN);
357 	if (so->so_state & SS_ISDISCONNECTING)
358 		return (EALREADY);
359 	error = (*so->so_proto->pr_usrreq)(so, PRU_DISCONNECT, NULL, NULL,
360 	    NULL, curproc);
361 	return (error);
362 }
363 
364 int m_getuio(struct mbuf **, int, long, struct uio *);
365 
366 #define	SBLOCKWAIT(f)	(((f) & MSG_DONTWAIT) ? M_NOWAIT : M_WAITOK)
367 /*
368  * Send on a socket.
369  * If send must go all at once and message is larger than
370  * send buffering, then hard error.
371  * Lock against other senders.
372  * If must go all at once and not enough room now, then
373  * inform user that this would block and do nothing.
374  * Otherwise, if nonblocking, send as much as possible.
375  * The data to be sent is described by "uio" if nonzero,
376  * otherwise by the mbuf chain "top" (which must be null
377  * if uio is not).  Data provided in mbuf chain must be small
378  * enough to send all at once.
379  *
380  * Returns nonzero on error, timeout or signal; callers
381  * must check for short counts if EINTR/ERESTART are returned.
382  * Data and control buffers are freed on return.
383  */
384 int
385 sosend(struct socket *so, struct mbuf *addr, struct uio *uio, struct mbuf *top,
386     struct mbuf *control, int flags)
387 {
388 	long space, clen = 0;
389 	size_t resid;
390 	int error, s;
391 	int atomic = sosendallatonce(so) || top;
392 
393 	if (uio)
394 		resid = uio->uio_resid;
395 	else
396 		resid = top->m_pkthdr.len;
397 	/* MSG_EOR on a SOCK_STREAM socket is invalid. */
398 	if (so->so_type == SOCK_STREAM && (flags & MSG_EOR)) {
399 		error = EINVAL;
400 		goto out;
401 	}
402 	if (uio && uio->uio_procp)
403 		uio->uio_procp->p_ru.ru_msgsnd++;
404 	if (control) {
405 		/*
406 		 * In theory clen should be unsigned (since control->m_len is).
407 		 * However, space must be signed, as it might be less than 0
408 		 * if we over-committed, and we must use a signed comparison
409 		 * of space and clen.
410 		 */
411 		clen = control->m_len;
412 		/* reserve extra space for AF_LOCAL's internalize */
413 		if (so->so_proto->pr_domain->dom_family == AF_LOCAL &&
414 		    clen >= CMSG_ALIGN(sizeof(struct cmsghdr)) &&
415 		    mtod(control, struct cmsghdr *)->cmsg_type == SCM_RIGHTS)
416 			clen = CMSG_SPACE(
417 			    (clen - CMSG_ALIGN(sizeof(struct cmsghdr))) *
418 			    (sizeof(struct file *) / sizeof(int)));
419 	}
420 
421 #define	snderr(errno)	{ error = errno; NET_UNLOCK(s); goto release; }
422 
423 restart:
424 	if ((error = sblock(&so->so_snd, SBLOCKWAIT(flags), NULL)) != 0)
425 		goto out;
426 	so->so_state |= SS_ISSENDING;
427 	do {
428 		NET_LOCK(s);
429 		if (so->so_state & SS_CANTSENDMORE)
430 			snderr(EPIPE);
431 		if (so->so_error) {
432 			error = so->so_error;
433 			so->so_error = 0;
434 			snderr(error);
435 		}
436 		if ((so->so_state & SS_ISCONNECTED) == 0) {
437 			if (so->so_proto->pr_flags & PR_CONNREQUIRED) {
438 				if (!(resid == 0 && clen != 0))
439 					snderr(ENOTCONN);
440 			} else if (addr == 0)
441 				snderr(EDESTADDRREQ);
442 		}
443 		space = sbspace(&so->so_snd);
444 		if (flags & MSG_OOB)
445 			space += 1024;
446 		if ((atomic && resid > so->so_snd.sb_hiwat) ||
447 		    (so->so_proto->pr_domain->dom_family != AF_LOCAL &&
448 		    clen > so->so_snd.sb_hiwat))
449 			snderr(EMSGSIZE);
450 		if (space < clen ||
451 		    (space - clen < resid &&
452 		    (atomic || space < so->so_snd.sb_lowat))) {
453 			if ((so->so_state & SS_NBIO) || (flags & MSG_DONTWAIT))
454 				snderr(EWOULDBLOCK);
455 			sbunlock(&so->so_snd);
456 			error = sbwait(&so->so_snd);
457 			so->so_state &= ~SS_ISSENDING;
458 			NET_UNLOCK(s);
459 			if (error)
460 				goto out;
461 			goto restart;
462 		}
463 		NET_UNLOCK(s);
464 		space -= clen;
465 		do {
466 			if (uio == NULL) {
467 				/*
468 				 * Data is prepackaged in "top".
469 				 */
470 				resid = 0;
471 				if (flags & MSG_EOR)
472 					top->m_flags |= M_EOR;
473 			} else {
474 				error = m_getuio(&top, atomic,
475 				    space, uio);
476 				if (error)
477 					goto release;
478 				space -= top->m_pkthdr.len;
479 				resid = uio->uio_resid;
480 				if (flags & MSG_EOR)
481 					top->m_flags |= M_EOR;
482 			}
483 			NET_LOCK(s);
484 			if (resid == 0)
485 				so->so_state &= ~SS_ISSENDING;
486 			error = (*so->so_proto->pr_usrreq)(so,
487 			    (flags & MSG_OOB) ? PRU_SENDOOB : PRU_SEND,
488 			    top, addr, control, curproc);
489 			NET_UNLOCK(s);
490 			clen = 0;
491 			control = NULL;
492 			top = NULL;
493 			if (error)
494 				goto release;
495 		} while (resid && space > 0);
496 	} while (resid);
497 
498 release:
499 	so->so_state &= ~SS_ISSENDING;
500 	sbunlock(&so->so_snd);
501 out:
502 	m_freem(top);
503 	m_freem(control);
504 	return (error);
505 }
506 
507 int
508 m_getuio(struct mbuf **mp, int atomic, long space, struct uio *uio)
509 {
510 	struct mbuf *m, *top = NULL;
511 	struct mbuf **nextp = &top;
512 	u_long len, mlen;
513 	size_t resid = uio->uio_resid;
514 	int error;
515 
516 	do {
517 		if (top == NULL) {
518 			MGETHDR(m, M_WAIT, MT_DATA);
519 			mlen = MHLEN;
520 			m->m_pkthdr.len = 0;
521 			m->m_pkthdr.ph_ifidx = 0;
522 		} else {
523 			MGET(m, M_WAIT, MT_DATA);
524 			mlen = MLEN;
525 		}
526 		/* chain mbuf together */
527 		*nextp = m;
528 		nextp = &m->m_next;
529 
530 		resid = ulmin(resid, space);
531 		if (resid >= MINCLSIZE) {
532 			MCLGETI(m, M_NOWAIT, NULL, ulmin(resid, MAXMCLBYTES));
533 			if ((m->m_flags & M_EXT) == 0)
534 				MCLGETI(m, M_NOWAIT, NULL, MCLBYTES);
535 			if ((m->m_flags & M_EXT) == 0)
536 				goto nopages;
537 			mlen = m->m_ext.ext_size;
538 			len = ulmin(mlen, resid);
539 			/*
540 			 * For datagram protocols, leave room
541 			 * for protocol headers in first mbuf.
542 			 */
543 			if (atomic && top == NULL && len < mlen - max_hdr)
544 				m->m_data += max_hdr;
545 		} else {
546 nopages:
547 			len = ulmin(mlen, resid);
548 			/*
549 			 * For datagram protocols, leave room
550 			 * for protocol headers in first mbuf.
551 			 */
552 			if (atomic && top == NULL && len < mlen - max_hdr)
553 				MH_ALIGN(m, len);
554 		}
555 
556 		error = uiomove(mtod(m, caddr_t), len, uio);
557 		if (error) {
558 			m_freem(top);
559 			return (error);
560 		}
561 
562 		/* adjust counters */
563 		resid = uio->uio_resid;
564 		space -= len;
565 		m->m_len = len;
566 		top->m_pkthdr.len += len;
567 
568 		/* Is there more space and more data? */
569 	} while (space > 0 && resid > 0);
570 
571 	*mp = top;
572 	return 0;
573 }
574 
575 /*
576  * Following replacement or removal of the first mbuf on the first
577  * mbuf chain of a socket buffer, push necessary state changes back
578  * into the socket buffer so that other consumers see the values
579  * consistently.  'nextrecord' is the callers locally stored value of
580  * the original value of sb->sb_mb->m_nextpkt which must be restored
581  * when the lead mbuf changes.  NOTE: 'nextrecord' may be NULL.
582  */
583 void
584 sbsync(struct sockbuf *sb, struct mbuf *nextrecord)
585 {
586 
587 	/*
588 	 * First, update for the new value of nextrecord.  If necessary,
589 	 * make it the first record.
590 	 */
591 	if (sb->sb_mb != NULL)
592 		sb->sb_mb->m_nextpkt = nextrecord;
593 	else
594 		sb->sb_mb = nextrecord;
595 
596 	/*
597 	 * Now update any dependent socket buffer fields to reflect
598 	 * the new state.  This is an inline of SB_EMPTY_FIXUP, with
599 	 * the addition of a second clause that takes care of the
600 	 * case where sb_mb has been updated, but remains the last
601 	 * record.
602 	 */
603 	if (sb->sb_mb == NULL) {
604 		sb->sb_mbtail = NULL;
605 		sb->sb_lastrecord = NULL;
606 	} else if (sb->sb_mb->m_nextpkt == NULL)
607 		sb->sb_lastrecord = sb->sb_mb;
608 }
609 
610 /*
611  * Implement receive operations on a socket.
612  * We depend on the way that records are added to the sockbuf
613  * by sbappend*.  In particular, each record (mbufs linked through m_next)
614  * must begin with an address if the protocol so specifies,
615  * followed by an optional mbuf or mbufs containing ancillary data,
616  * and then zero or more mbufs of data.
617  * In order to avoid blocking network for the entire time here, we splx()
618  * and release NET_LOCK() while doing the actual copy to user space.
619  * Although the sockbuf is locked, new data may still be appended,
620  * and thus we must maintain consistency of the sockbuf during that time.
621  *
622  * The caller may receive the data as a single mbuf chain by supplying
623  * an mbuf **mp0 for use in returning the chain.  The uio is then used
624  * only for the count in uio_resid.
625  */
626 int
627 soreceive(struct socket *so, struct mbuf **paddr, struct uio *uio,
628     struct mbuf **mp0, struct mbuf **controlp, int *flagsp,
629     socklen_t controllen)
630 {
631 	struct mbuf *m, **mp;
632 	struct mbuf *cm;
633 	u_long len, offset, moff;
634 	int flags, error, s, type, uio_error = 0;
635 	struct protosw *pr = so->so_proto;
636 	struct mbuf *nextrecord;
637 	size_t resid, orig_resid = uio->uio_resid;
638 
639 	mp = mp0;
640 	if (paddr)
641 		*paddr = 0;
642 	if (controlp)
643 		*controlp = 0;
644 	if (flagsp)
645 		flags = *flagsp &~ MSG_EOR;
646 	else
647 		flags = 0;
648 	if (so->so_state & SS_NBIO)
649 		flags |= MSG_DONTWAIT;
650 	if (flags & MSG_OOB) {
651 		m = m_get(M_WAIT, MT_DATA);
652 		NET_LOCK(s);
653 		error = (*pr->pr_usrreq)(so, PRU_RCVOOB, m,
654 		    (struct mbuf *)(long)(flags & MSG_PEEK), NULL, curproc);
655 		NET_UNLOCK(s);
656 		if (error)
657 			goto bad;
658 		do {
659 			error = uiomove(mtod(m, caddr_t),
660 			    ulmin(uio->uio_resid, m->m_len), uio);
661 			m = m_free(m);
662 		} while (uio->uio_resid && error == 0 && m);
663 bad:
664 		m_freem(m);
665 		return (error);
666 	}
667 	if (mp)
668 		*mp = NULL;
669 
670 restart:
671 	if ((error = sblock(&so->so_rcv, SBLOCKWAIT(flags), NULL)) != 0)
672 		return (error);
673 	NET_LOCK(s);
674 
675 	m = so->so_rcv.sb_mb;
676 #ifdef SOCKET_SPLICE
677 	if (isspliced(so))
678 		m = NULL;
679 #endif /* SOCKET_SPLICE */
680 	/*
681 	 * If we have less data than requested, block awaiting more
682 	 * (subject to any timeout) if:
683 	 *   1. the current count is less than the low water mark,
684 	 *   2. MSG_WAITALL is set, and it is possible to do the entire
685 	 *	receive operation at once if we block (resid <= hiwat), or
686 	 *   3. MSG_DONTWAIT is not set.
687 	 * If MSG_WAITALL is set but resid is larger than the receive buffer,
688 	 * we have to do the receive in sections, and thus risk returning
689 	 * a short count if a timeout or signal occurs after we start.
690 	 */
691 	if (m == NULL || (((flags & MSG_DONTWAIT) == 0 &&
692 	    so->so_rcv.sb_cc < uio->uio_resid) &&
693 	    (so->so_rcv.sb_cc < so->so_rcv.sb_lowat ||
694 	    ((flags & MSG_WAITALL) && uio->uio_resid <= so->so_rcv.sb_hiwat)) &&
695 	    m->m_nextpkt == NULL && (pr->pr_flags & PR_ATOMIC) == 0)) {
696 #ifdef DIAGNOSTIC
697 		if (m == NULL && so->so_rcv.sb_cc)
698 #ifdef SOCKET_SPLICE
699 		    if (!isspliced(so))
700 #endif /* SOCKET_SPLICE */
701 			panic("receive 1: so %p, so_type %d, sb_cc %lu",
702 			    so, so->so_type, so->so_rcv.sb_cc);
703 #endif
704 		if (so->so_error) {
705 			if (m)
706 				goto dontblock;
707 			error = so->so_error;
708 			if ((flags & MSG_PEEK) == 0)
709 				so->so_error = 0;
710 			goto release;
711 		}
712 		if (so->so_state & SS_CANTRCVMORE) {
713 			if (m)
714 				goto dontblock;
715 			else if (so->so_rcv.sb_cc == 0)
716 				goto release;
717 		}
718 		for (; m; m = m->m_next)
719 			if (m->m_type == MT_OOBDATA  || (m->m_flags & M_EOR)) {
720 				m = so->so_rcv.sb_mb;
721 				goto dontblock;
722 			}
723 		if ((so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING)) == 0 &&
724 		    (so->so_proto->pr_flags & PR_CONNREQUIRED)) {
725 			error = ENOTCONN;
726 			goto release;
727 		}
728 		if (uio->uio_resid == 0 && controlp == NULL)
729 			goto release;
730 		if ((so->so_state & SS_NBIO) || (flags & MSG_DONTWAIT)) {
731 			error = EWOULDBLOCK;
732 			goto release;
733 		}
734 		SBLASTRECORDCHK(&so->so_rcv, "soreceive sbwait 1");
735 		SBLASTMBUFCHK(&so->so_rcv, "soreceive sbwait 1");
736 		sbunlock(&so->so_rcv);
737 		error = sbwait(&so->so_rcv);
738 		NET_UNLOCK(s);
739 		if (error)
740 			return (error);
741 		goto restart;
742 	}
743 dontblock:
744 	/*
745 	 * On entry here, m points to the first record of the socket buffer.
746 	 * From this point onward, we maintain 'nextrecord' as a cache of the
747 	 * pointer to the next record in the socket buffer.  We must keep the
748 	 * various socket buffer pointers and local stack versions of the
749 	 * pointers in sync, pushing out modifications before operations that
750 	 * may sleep, and re-reading them afterwards.
751 	 *
752 	 * Otherwise, we will race with the network stack appending new data
753 	 * or records onto the socket buffer by using inconsistent/stale
754 	 * versions of the field, possibly resulting in socket buffer
755 	 * corruption.
756 	 */
757 	if (uio->uio_procp)
758 		uio->uio_procp->p_ru.ru_msgrcv++;
759 	KASSERT(m == so->so_rcv.sb_mb);
760 	SBLASTRECORDCHK(&so->so_rcv, "soreceive 1");
761 	SBLASTMBUFCHK(&so->so_rcv, "soreceive 1");
762 	nextrecord = m->m_nextpkt;
763 	if (pr->pr_flags & PR_ADDR) {
764 #ifdef DIAGNOSTIC
765 		if (m->m_type != MT_SONAME)
766 			panic("receive 1a: so %p, so_type %d, m %p, m_type %d",
767 			    so, so->so_type, m, m->m_type);
768 #endif
769 		orig_resid = 0;
770 		if (flags & MSG_PEEK) {
771 			if (paddr)
772 				*paddr = m_copym(m, 0, m->m_len, M_NOWAIT);
773 			m = m->m_next;
774 		} else {
775 			sbfree(&so->so_rcv, m);
776 			if (paddr) {
777 				*paddr = m;
778 				so->so_rcv.sb_mb = m->m_next;
779 				m->m_next = 0;
780 				m = so->so_rcv.sb_mb;
781 			} else {
782 				so->so_rcv.sb_mb = m_free(m);
783 				m = so->so_rcv.sb_mb;
784 			}
785 			sbsync(&so->so_rcv, nextrecord);
786 		}
787 	}
788 	while (m && m->m_type == MT_CONTROL && error == 0) {
789 		if (flags & MSG_PEEK) {
790 			if (controlp)
791 				*controlp = m_copym(m, 0, m->m_len, M_NOWAIT);
792 			m = m->m_next;
793 		} else {
794 			sbfree(&so->so_rcv, m);
795 			so->so_rcv.sb_mb = m->m_next;
796 			m->m_nextpkt = m->m_next = NULL;
797 			cm = m;
798 			m = so->so_rcv.sb_mb;
799 			sbsync(&so->so_rcv, nextrecord);
800 			if (controlp) {
801 				if (pr->pr_domain->dom_externalize &&
802 				    mtod(cm, struct cmsghdr *)->cmsg_type ==
803 				    SCM_RIGHTS)
804 				   error = (*pr->pr_domain->dom_externalize)(cm,
805 				       controllen, flags);
806 				*controlp = cm;
807 			} else {
808 				/*
809 				 * Dispose of any SCM_RIGHTS message that went
810 				 * through the read path rather than recv.
811 				 */
812 				if (pr->pr_domain->dom_dispose &&
813 				    mtod(cm, struct cmsghdr *)->cmsg_type == SCM_RIGHTS)
814 					pr->pr_domain->dom_dispose(cm);
815 				m_free(cm);
816 			}
817 		}
818 		if (m != NULL)
819 			nextrecord = so->so_rcv.sb_mb->m_nextpkt;
820 		else
821 			nextrecord = so->so_rcv.sb_mb;
822 		if (controlp) {
823 			orig_resid = 0;
824 			controlp = &(*controlp)->m_next;
825 		}
826 	}
827 
828 	/* If m is non-NULL, we have some data to read. */
829 	if (m) {
830 		type = m->m_type;
831 		if (type == MT_OOBDATA)
832 			flags |= MSG_OOB;
833 		if (m->m_flags & M_BCAST)
834 			flags |= MSG_BCAST;
835 		if (m->m_flags & M_MCAST)
836 			flags |= MSG_MCAST;
837 	}
838 	SBLASTRECORDCHK(&so->so_rcv, "soreceive 2");
839 	SBLASTMBUFCHK(&so->so_rcv, "soreceive 2");
840 
841 	moff = 0;
842 	offset = 0;
843 	while (m && uio->uio_resid > 0 && error == 0) {
844 		if (m->m_type == MT_OOBDATA) {
845 			if (type != MT_OOBDATA)
846 				break;
847 		} else if (type == MT_OOBDATA)
848 			break;
849 #ifdef DIAGNOSTIC
850 		else if (m->m_type != MT_DATA && m->m_type != MT_HEADER)
851 			panic("receive 3: so %p, so_type %d, m %p, m_type %d",
852 			    so, so->so_type, m, m->m_type);
853 #endif
854 		so->so_state &= ~SS_RCVATMARK;
855 		len = uio->uio_resid;
856 		if (so->so_oobmark && len > so->so_oobmark - offset)
857 			len = so->so_oobmark - offset;
858 		if (len > m->m_len - moff)
859 			len = m->m_len - moff;
860 		/*
861 		 * If mp is set, just pass back the mbufs.
862 		 * Otherwise copy them out via the uio, then free.
863 		 * Sockbuf must be consistent here (points to current mbuf,
864 		 * it points to next record) when we drop priority;
865 		 * we must note any additions to the sockbuf when we
866 		 * block interrupts again.
867 		 */
868 		if (mp == NULL && uio_error == 0) {
869 			SBLASTRECORDCHK(&so->so_rcv, "soreceive uiomove");
870 			SBLASTMBUFCHK(&so->so_rcv, "soreceive uiomove");
871 			resid = uio->uio_resid;
872 			NET_UNLOCK(s);
873 			uio_error = uiomove(mtod(m, caddr_t) + moff, len, uio);
874 			NET_LOCK(s);
875 			if (uio_error)
876 				uio->uio_resid = resid - len;
877 		} else
878 			uio->uio_resid -= len;
879 		if (len == m->m_len - moff) {
880 			if (m->m_flags & M_EOR)
881 				flags |= MSG_EOR;
882 			if (flags & MSG_PEEK) {
883 				m = m->m_next;
884 				moff = 0;
885 			} else {
886 				nextrecord = m->m_nextpkt;
887 				sbfree(&so->so_rcv, m);
888 				if (mp) {
889 					*mp = m;
890 					mp = &m->m_next;
891 					so->so_rcv.sb_mb = m = m->m_next;
892 					*mp = NULL;
893 				} else {
894 					so->so_rcv.sb_mb = m_free(m);
895 					m = so->so_rcv.sb_mb;
896 				}
897 				/*
898 				 * If m != NULL, we also know that
899 				 * so->so_rcv.sb_mb != NULL.
900 				 */
901 				KASSERT(so->so_rcv.sb_mb == m);
902 				if (m) {
903 					m->m_nextpkt = nextrecord;
904 					if (nextrecord == NULL)
905 						so->so_rcv.sb_lastrecord = m;
906 				} else {
907 					so->so_rcv.sb_mb = nextrecord;
908 					SB_EMPTY_FIXUP(&so->so_rcv);
909 				}
910 				SBLASTRECORDCHK(&so->so_rcv, "soreceive 3");
911 				SBLASTMBUFCHK(&so->so_rcv, "soreceive 3");
912 			}
913 		} else {
914 			if (flags & MSG_PEEK)
915 				moff += len;
916 			else {
917 				if (mp)
918 					*mp = m_copym(m, 0, len, M_WAIT);
919 				m->m_data += len;
920 				m->m_len -= len;
921 				so->so_rcv.sb_cc -= len;
922 				so->so_rcv.sb_datacc -= len;
923 			}
924 		}
925 		if (so->so_oobmark) {
926 			if ((flags & MSG_PEEK) == 0) {
927 				so->so_oobmark -= len;
928 				if (so->so_oobmark == 0) {
929 					so->so_state |= SS_RCVATMARK;
930 					break;
931 				}
932 			} else {
933 				offset += len;
934 				if (offset == so->so_oobmark)
935 					break;
936 			}
937 		}
938 		if (flags & MSG_EOR)
939 			break;
940 		/*
941 		 * If the MSG_WAITALL flag is set (for non-atomic socket),
942 		 * we must not quit until "uio->uio_resid == 0" or an error
943 		 * termination.  If a signal/timeout occurs, return
944 		 * with a short count but without error.
945 		 * Keep sockbuf locked against other readers.
946 		 */
947 		while (flags & MSG_WAITALL && m == NULL && uio->uio_resid > 0 &&
948 		    !sosendallatonce(so) && !nextrecord) {
949 			if (so->so_error || so->so_state & SS_CANTRCVMORE)
950 				break;
951 			SBLASTRECORDCHK(&so->so_rcv, "soreceive sbwait 2");
952 			SBLASTMBUFCHK(&so->so_rcv, "soreceive sbwait 2");
953 			error = sbwait(&so->so_rcv);
954 			if (error) {
955 				sbunlock(&so->so_rcv);
956 				NET_UNLOCK(s);
957 				return (0);
958 			}
959 			if ((m = so->so_rcv.sb_mb) != NULL)
960 				nextrecord = m->m_nextpkt;
961 		}
962 	}
963 
964 	if (m && pr->pr_flags & PR_ATOMIC) {
965 		flags |= MSG_TRUNC;
966 		if ((flags & MSG_PEEK) == 0)
967 			(void) sbdroprecord(&so->so_rcv);
968 	}
969 	if ((flags & MSG_PEEK) == 0) {
970 		if (m == NULL) {
971 			/*
972 			 * First part is an inline SB_EMPTY_FIXUP().  Second
973 			 * part makes sure sb_lastrecord is up-to-date if
974 			 * there is still data in the socket buffer.
975 			 */
976 			so->so_rcv.sb_mb = nextrecord;
977 			if (so->so_rcv.sb_mb == NULL) {
978 				so->so_rcv.sb_mbtail = NULL;
979 				so->so_rcv.sb_lastrecord = NULL;
980 			} else if (nextrecord->m_nextpkt == NULL)
981 				so->so_rcv.sb_lastrecord = nextrecord;
982 		}
983 		SBLASTRECORDCHK(&so->so_rcv, "soreceive 4");
984 		SBLASTMBUFCHK(&so->so_rcv, "soreceive 4");
985 		if (pr->pr_flags & PR_WANTRCVD && so->so_pcb)
986 			(*pr->pr_usrreq)(so, PRU_RCVD, NULL,
987 			    (struct mbuf *)(long)flags, NULL, curproc);
988 	}
989 	if (orig_resid == uio->uio_resid && orig_resid &&
990 	    (flags & MSG_EOR) == 0 && (so->so_state & SS_CANTRCVMORE) == 0) {
991 		sbunlock(&so->so_rcv);
992 		NET_UNLOCK(s);
993 		goto restart;
994 	}
995 
996 	if (uio_error)
997 		error = uio_error;
998 
999 	if (flagsp)
1000 		*flagsp |= flags;
1001 release:
1002 	sbunlock(&so->so_rcv);
1003 	NET_UNLOCK(s);
1004 	return (error);
1005 }
1006 
1007 int
1008 soshutdown(struct socket *so, int how)
1009 {
1010 	struct protosw *pr = so->so_proto;
1011 	int s, error = 0;
1012 
1013 	NET_LOCK(s);
1014 	switch (how) {
1015 	case SHUT_RD:
1016 	case SHUT_RDWR:
1017 		sorflush(so);
1018 		if (how == SHUT_RD)
1019 			break;
1020 		/* FALLTHROUGH */
1021 	case SHUT_WR:
1022 		error = (*pr->pr_usrreq)(so, PRU_SHUTDOWN, NULL, NULL, NULL,
1023 		    curproc);
1024 		break;
1025 	default:
1026 		error = EINVAL;
1027 		break;
1028 	}
1029 	NET_UNLOCK(s);
1030 
1031 	return (error);
1032 }
1033 
1034 void
1035 sorflush(struct socket *so)
1036 {
1037 	struct sockbuf *sb = &so->so_rcv;
1038 	struct protosw *pr = so->so_proto;
1039 	struct sockbuf asb;
1040 
1041 	sb->sb_flags |= SB_NOINTR;
1042 	(void) sblock(sb, M_WAITOK, NULL);
1043 	socantrcvmore(so);
1044 	sbunlock(sb);
1045 	asb = *sb;
1046 	memset(sb, 0, sizeof (*sb));
1047 	/* XXX - the memset stomps all over so_rcv */
1048 	if (asb.sb_flags & SB_KNOTE) {
1049 		sb->sb_sel.si_note = asb.sb_sel.si_note;
1050 		sb->sb_flags = SB_KNOTE;
1051 	}
1052 	if (pr->pr_flags & PR_RIGHTS && pr->pr_domain->dom_dispose)
1053 		(*pr->pr_domain->dom_dispose)(asb.sb_mb);
1054 	sbrelease(&asb);
1055 }
1056 
1057 #ifdef SOCKET_SPLICE
1058 
1059 #define so_splicelen	so_sp->ssp_len
1060 #define so_splicemax	so_sp->ssp_max
1061 #define so_idletv	so_sp->ssp_idletv
1062 #define so_idleto	so_sp->ssp_idleto
1063 #define so_splicetask	so_sp->ssp_task
1064 
1065 int
1066 sosplice(struct socket *so, int fd, off_t max, struct timeval *tv)
1067 {
1068 	struct file	*fp;
1069 	struct socket	*sosp;
1070 	int		 s, error = 0;
1071 
1072 	if (sosplice_taskq == NULL)
1073 		sosplice_taskq = taskq_create("sosplice", 1, IPL_SOFTNET,
1074 		    TASKQ_CANTSLEEP);
1075 	if (sosplice_taskq == NULL)
1076 		return (ENOMEM);
1077 
1078 	if ((so->so_proto->pr_flags & PR_SPLICE) == 0)
1079 		return (EPROTONOSUPPORT);
1080 	if (so->so_options & SO_ACCEPTCONN)
1081 		return (EOPNOTSUPP);
1082 	if ((so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING)) == 0 &&
1083 	    (so->so_proto->pr_flags & PR_CONNREQUIRED))
1084 		return (ENOTCONN);
1085 	if (so->so_sp == NULL)
1086 		so->so_sp = pool_get(&sosplice_pool, PR_WAITOK | PR_ZERO);
1087 
1088 	/* If no fd is given, unsplice by removing existing link. */
1089 	if (fd < 0) {
1090 		/* Lock receive buffer. */
1091 		if ((error = sblock(&so->so_rcv,
1092 		    (so->so_state & SS_NBIO) ? M_NOWAIT : M_WAITOK, NULL)) != 0)
1093 			return (error);
1094 		NET_LOCK(s);
1095 		if (so->so_sp->ssp_socket)
1096 			sounsplice(so, so->so_sp->ssp_socket, 1);
1097 		NET_UNLOCK(s);
1098 		sbunlock(&so->so_rcv);
1099 		return (0);
1100 	}
1101 
1102 	if (max && max < 0)
1103 		return (EINVAL);
1104 
1105 	if (tv && (tv->tv_sec < 0 || tv->tv_usec < 0))
1106 		return (EINVAL);
1107 
1108 	/* Find sosp, the drain socket where data will be spliced into. */
1109 	if ((error = getsock(curproc, fd, &fp)) != 0)
1110 		return (error);
1111 	sosp = fp->f_data;
1112 	if (sosp->so_sp == NULL)
1113 		sosp->so_sp = pool_get(&sosplice_pool, PR_WAITOK | PR_ZERO);
1114 
1115 	/* Lock both receive and send buffer. */
1116 	if ((error = sblock(&so->so_rcv,
1117 	    (so->so_state & SS_NBIO) ? M_NOWAIT : M_WAITOK, NULL)) != 0) {
1118 		FRELE(fp, curproc);
1119 		return (error);
1120 	}
1121 	if ((error = sblock(&sosp->so_snd, M_WAITOK, NULL)) != 0) {
1122 		sbunlock(&so->so_rcv);
1123 		FRELE(fp, curproc);
1124 		return (error);
1125 	}
1126 	NET_LOCK(s);
1127 
1128 	if (so->so_sp->ssp_socket || sosp->so_sp->ssp_soback) {
1129 		error = EBUSY;
1130 		goto release;
1131 	}
1132 	if (sosp->so_proto->pr_usrreq != so->so_proto->pr_usrreq) {
1133 		error = EPROTONOSUPPORT;
1134 		goto release;
1135 	}
1136 	if (sosp->so_options & SO_ACCEPTCONN) {
1137 		error = EOPNOTSUPP;
1138 		goto release;
1139 	}
1140 	if ((sosp->so_state & (SS_ISCONNECTED|SS_ISCONNECTING)) == 0) {
1141 		error = ENOTCONN;
1142 		goto release;
1143 	}
1144 
1145 	/* Splice so and sosp together. */
1146 	so->so_sp->ssp_socket = sosp;
1147 	sosp->so_sp->ssp_soback = so;
1148 	so->so_splicelen = 0;
1149 	so->so_splicemax = max;
1150 	if (tv)
1151 		so->so_idletv = *tv;
1152 	else
1153 		timerclear(&so->so_idletv);
1154 	timeout_set(&so->so_idleto, soidle, so);
1155 	task_set(&so->so_splicetask, sotask, so);
1156 
1157 	/*
1158 	 * To prevent softnet interrupt from calling somove() while
1159 	 * we sleep, the socket buffers are not marked as spliced yet.
1160 	 */
1161 	if (somove(so, M_WAIT)) {
1162 		so->so_rcv.sb_flagsintr |= SB_SPLICE;
1163 		sosp->so_snd.sb_flagsintr |= SB_SPLICE;
1164 	}
1165 
1166  release:
1167 	NET_UNLOCK(s);
1168 	sbunlock(&sosp->so_snd);
1169 	sbunlock(&so->so_rcv);
1170 	FRELE(fp, curproc);
1171 	return (error);
1172 }
1173 
1174 void
1175 sounsplice(struct socket *so, struct socket *sosp, int wakeup)
1176 {
1177 	NET_ASSERT_LOCKED();
1178 
1179 	task_del(sosplice_taskq, &so->so_splicetask);
1180 	timeout_del(&so->so_idleto);
1181 	sosp->so_snd.sb_flagsintr &= ~SB_SPLICE;
1182 	so->so_rcv.sb_flagsintr &= ~SB_SPLICE;
1183 	so->so_sp->ssp_socket = sosp->so_sp->ssp_soback = NULL;
1184 	if (wakeup && soreadable(so))
1185 		sorwakeup(so);
1186 }
1187 
1188 void
1189 soidle(void *arg)
1190 {
1191 	struct socket *so = arg;
1192 	int s;
1193 
1194 	NET_LOCK(s);
1195 	if (so->so_rcv.sb_flagsintr & SB_SPLICE) {
1196 		so->so_error = ETIMEDOUT;
1197 		sounsplice(so, so->so_sp->ssp_socket, 1);
1198 	}
1199 	NET_UNLOCK(s);
1200 }
1201 
1202 void
1203 sotask(void *arg)
1204 {
1205 	struct socket *so = arg;
1206 	int s;
1207 
1208 	NET_LOCK(s);
1209 	if (so->so_rcv.sb_flagsintr & SB_SPLICE) {
1210 		/*
1211 		 * We may not sleep here as sofree() and unsplice() may be
1212 		 * called from softnet interrupt context.  This would remove
1213 		 * the socket during somove().
1214 		 */
1215 		somove(so, M_DONTWAIT);
1216 	}
1217 	NET_UNLOCK(s);
1218 
1219 	/* Avoid user land starvation. */
1220 	yield();
1221 }
1222 
1223 /*
1224  * Move data from receive buffer of spliced source socket to send
1225  * buffer of drain socket.  Try to move as much as possible in one
1226  * big chunk.  It is a TCP only implementation.
1227  * Return value 0 means splicing has been finished, 1 continue.
1228  */
1229 int
1230 somove(struct socket *so, int wait)
1231 {
1232 	struct socket	*sosp = so->so_sp->ssp_socket;
1233 	struct mbuf	*m, **mp, *nextrecord;
1234 	u_long		 len, off, oobmark;
1235 	long		 space;
1236 	int		 error = 0, maxreached = 0;
1237 	short		 state;
1238 
1239 	NET_ASSERT_LOCKED();
1240 
1241  nextpkt:
1242 	if (so->so_error) {
1243 		error = so->so_error;
1244 		goto release;
1245 	}
1246 	if (sosp->so_state & SS_CANTSENDMORE) {
1247 		error = EPIPE;
1248 		goto release;
1249 	}
1250 	if (sosp->so_error && sosp->so_error != ETIMEDOUT &&
1251 	    sosp->so_error != EFBIG && sosp->so_error != ELOOP) {
1252 		error = sosp->so_error;
1253 		goto release;
1254 	}
1255 	if ((sosp->so_state & SS_ISCONNECTED) == 0)
1256 		goto release;
1257 
1258 	/* Calculate how many bytes can be copied now. */
1259 	len = so->so_rcv.sb_datacc;
1260 	if (so->so_splicemax) {
1261 		KASSERT(so->so_splicelen < so->so_splicemax);
1262 		if (so->so_splicemax <= so->so_splicelen + len) {
1263 			len = so->so_splicemax - so->so_splicelen;
1264 			maxreached = 1;
1265 		}
1266 	}
1267 	space = sbspace(&sosp->so_snd);
1268 	if (so->so_oobmark && so->so_oobmark < len &&
1269 	    so->so_oobmark < space + 1024)
1270 		space += 1024;
1271 	if (space <= 0) {
1272 		maxreached = 0;
1273 		goto release;
1274 	}
1275 	if (space < len) {
1276 		maxreached = 0;
1277 		if (space < sosp->so_snd.sb_lowat)
1278 			goto release;
1279 		len = space;
1280 	}
1281 	sosp->so_state |= SS_ISSENDING;
1282 
1283 	SBLASTRECORDCHK(&so->so_rcv, "somove 1");
1284 	SBLASTMBUFCHK(&so->so_rcv, "somove 1");
1285 	m = so->so_rcv.sb_mb;
1286 	if (m == NULL)
1287 		goto release;
1288 	nextrecord = m->m_nextpkt;
1289 
1290 	/* Drop address and control information not used with splicing. */
1291 	if (so->so_proto->pr_flags & PR_ADDR) {
1292 #ifdef DIAGNOSTIC
1293 		if (m->m_type != MT_SONAME)
1294 			panic("somove soname: so %p, so_type %d, m %p, "
1295 			    "m_type %d", so, so->so_type, m, m->m_type);
1296 #endif
1297 		m = m->m_next;
1298 	}
1299 	while (m && m->m_type == MT_CONTROL)
1300 		m = m->m_next;
1301 	if (m == NULL) {
1302 		sbdroprecord(&so->so_rcv);
1303 		if (so->so_proto->pr_flags & PR_WANTRCVD && so->so_pcb)
1304 			(so->so_proto->pr_usrreq)(so, PRU_RCVD, NULL,
1305 			    NULL, NULL, NULL);
1306 		goto nextpkt;
1307 	}
1308 
1309 	/*
1310 	 * By splicing sockets connected to localhost, userland might create a
1311 	 * loop.  Dissolve splicing with error if loop is detected by counter.
1312 	 */
1313 	if ((m->m_flags & M_PKTHDR) && m->m_pkthdr.ph_loopcnt++ >= M_MAXLOOP) {
1314 		error = ELOOP;
1315 		goto release;
1316 	}
1317 
1318 	if (so->so_proto->pr_flags & PR_ATOMIC) {
1319 		if ((m->m_flags & M_PKTHDR) == 0)
1320 			panic("somove !PKTHDR: so %p, so_type %d, m %p, "
1321 			    "m_type %d", so, so->so_type, m, m->m_type);
1322 		if (sosp->so_snd.sb_hiwat < m->m_pkthdr.len) {
1323 			error = EMSGSIZE;
1324 			goto release;
1325 		}
1326 		if (len < m->m_pkthdr.len)
1327 			goto release;
1328 		if (m->m_pkthdr.len < len) {
1329 			maxreached = 0;
1330 			len = m->m_pkthdr.len;
1331 		}
1332 		/*
1333 		 * Throw away the name mbuf after it has been assured
1334 		 * that the whole first record can be processed.
1335 		 */
1336 		m = so->so_rcv.sb_mb;
1337 		sbfree(&so->so_rcv, m);
1338 		so->so_rcv.sb_mb = m_free(m);
1339 		sbsync(&so->so_rcv, nextrecord);
1340 	}
1341 	/*
1342 	 * Throw away the control mbufs after it has been assured
1343 	 * that the whole first record can be processed.
1344 	 */
1345 	m = so->so_rcv.sb_mb;
1346 	while (m && m->m_type == MT_CONTROL) {
1347 		sbfree(&so->so_rcv, m);
1348 		so->so_rcv.sb_mb = m_free(m);
1349 		m = so->so_rcv.sb_mb;
1350 		sbsync(&so->so_rcv, nextrecord);
1351 	}
1352 
1353 	SBLASTRECORDCHK(&so->so_rcv, "somove 2");
1354 	SBLASTMBUFCHK(&so->so_rcv, "somove 2");
1355 
1356 	/* Take at most len mbufs out of receive buffer. */
1357 	for (off = 0, mp = &m; off <= len && *mp;
1358 	    off += (*mp)->m_len, mp = &(*mp)->m_next) {
1359 		u_long size = len - off;
1360 
1361 #ifdef DIAGNOSTIC
1362 		if ((*mp)->m_type != MT_DATA && (*mp)->m_type != MT_HEADER)
1363 			panic("somove type: so %p, so_type %d, m %p, "
1364 			    "m_type %d", so, so->so_type, *mp, (*mp)->m_type);
1365 #endif
1366 		if ((*mp)->m_len > size) {
1367 			/*
1368 			 * Move only a partial mbuf at maximum splice length or
1369 			 * if the drain buffer is too small for this large mbuf.
1370 			 */
1371 			if (!maxreached && so->so_snd.sb_datacc > 0) {
1372 				len -= size;
1373 				break;
1374 			}
1375 			*mp = m_copym(so->so_rcv.sb_mb, 0, size, wait);
1376 			if (*mp == NULL) {
1377 				len -= size;
1378 				break;
1379 			}
1380 			so->so_rcv.sb_mb->m_data += size;
1381 			so->so_rcv.sb_mb->m_len -= size;
1382 			so->so_rcv.sb_cc -= size;
1383 			so->so_rcv.sb_datacc -= size;
1384 		} else {
1385 			*mp = so->so_rcv.sb_mb;
1386 			sbfree(&so->so_rcv, *mp);
1387 			so->so_rcv.sb_mb = (*mp)->m_next;
1388 			sbsync(&so->so_rcv, nextrecord);
1389 		}
1390 	}
1391 	*mp = NULL;
1392 
1393 	SBLASTRECORDCHK(&so->so_rcv, "somove 3");
1394 	SBLASTMBUFCHK(&so->so_rcv, "somove 3");
1395 	SBCHECK(&so->so_rcv);
1396 	if (m == NULL)
1397 		goto release;
1398 	m->m_nextpkt = NULL;
1399 	if (m->m_flags & M_PKTHDR) {
1400 		m_resethdr(m);
1401 		m->m_pkthdr.len = len;
1402 	}
1403 
1404 	/* Send window update to source peer as receive buffer has changed. */
1405 	if (so->so_proto->pr_flags & PR_WANTRCVD && so->so_pcb)
1406 		(so->so_proto->pr_usrreq)(so, PRU_RCVD, NULL,
1407 		    NULL, NULL, NULL);
1408 
1409 	/* Receive buffer did shrink by len bytes, adjust oob. */
1410 	state = so->so_state;
1411 	so->so_state &= ~SS_RCVATMARK;
1412 	oobmark = so->so_oobmark;
1413 	so->so_oobmark = oobmark > len ? oobmark - len : 0;
1414 	if (oobmark) {
1415 		if (oobmark == len)
1416 			so->so_state |= SS_RCVATMARK;
1417 		if (oobmark >= len)
1418 			oobmark = 0;
1419 	}
1420 
1421 	/*
1422 	 * Handle oob data.  If any malloc fails, ignore error.
1423 	 * TCP urgent data is not very reliable anyway.
1424 	 */
1425 	while (((state & SS_RCVATMARK) || oobmark) &&
1426 	    (so->so_options & SO_OOBINLINE)) {
1427 		struct mbuf *o = NULL;
1428 
1429 		if (state & SS_RCVATMARK) {
1430 			o = m_get(wait, MT_DATA);
1431 			state &= ~SS_RCVATMARK;
1432 		} else if (oobmark) {
1433 			o = m_split(m, oobmark, wait);
1434 			if (o) {
1435 				error = (*sosp->so_proto->pr_usrreq)(sosp,
1436 				    PRU_SEND, m, NULL, NULL, NULL);
1437 				if (error) {
1438 					if (sosp->so_state & SS_CANTSENDMORE)
1439 						error = EPIPE;
1440 					m_freem(o);
1441 					goto release;
1442 				}
1443 				len -= oobmark;
1444 				so->so_splicelen += oobmark;
1445 				m = o;
1446 				o = m_get(wait, MT_DATA);
1447 			}
1448 			oobmark = 0;
1449 		}
1450 		if (o) {
1451 			o->m_len = 1;
1452 			*mtod(o, caddr_t) = *mtod(m, caddr_t);
1453 			error = (*sosp->so_proto->pr_usrreq)(sosp, PRU_SENDOOB,
1454 			    o, NULL, NULL, NULL);
1455 			if (error) {
1456 				if (sosp->so_state & SS_CANTSENDMORE)
1457 					error = EPIPE;
1458 				m_freem(m);
1459 				goto release;
1460 			}
1461 			len -= 1;
1462 			so->so_splicelen += 1;
1463 			if (oobmark) {
1464 				oobmark -= 1;
1465 				if (oobmark == 0)
1466 					state |= SS_RCVATMARK;
1467 			}
1468 			m_adj(m, 1);
1469 		}
1470 	}
1471 
1472 	/* Append all remaining data to drain socket. */
1473 	if (so->so_rcv.sb_cc == 0 || maxreached)
1474 		sosp->so_state &= ~SS_ISSENDING;
1475 	error = (*sosp->so_proto->pr_usrreq)(sosp, PRU_SEND, m, NULL, NULL,
1476 	    NULL);
1477 	if (error) {
1478 		if (sosp->so_state & SS_CANTSENDMORE)
1479 			error = EPIPE;
1480 		goto release;
1481 	}
1482 	so->so_splicelen += len;
1483 
1484 	/* Move several packets if possible. */
1485 	if (!maxreached && nextrecord)
1486 		goto nextpkt;
1487 
1488  release:
1489 	sosp->so_state &= ~SS_ISSENDING;
1490 	if (!error && maxreached && so->so_splicemax == so->so_splicelen)
1491 		error = EFBIG;
1492 	if (error)
1493 		so->so_error = error;
1494 	if (((so->so_state & SS_CANTRCVMORE) && so->so_rcv.sb_cc == 0) ||
1495 	    (sosp->so_state & SS_CANTSENDMORE) || maxreached || error) {
1496 		sounsplice(so, sosp, 1);
1497 		return (0);
1498 	}
1499 	if (timerisset(&so->so_idletv))
1500 		timeout_add_tv(&so->so_idleto, &so->so_idletv);
1501 	return (1);
1502 }
1503 
1504 #endif /* SOCKET_SPLICE */
1505 
1506 void
1507 sorwakeup(struct socket *so)
1508 {
1509 	NET_ASSERT_LOCKED();
1510 
1511 #ifdef SOCKET_SPLICE
1512 	if (so->so_rcv.sb_flagsintr & SB_SPLICE) {
1513 		/*
1514 		 * TCP has a sendbuffer that can handle multiple packets
1515 		 * at once.  So queue the stream a bit to accumulate data.
1516 		 * The sosplice thread will call somove() later and send
1517 		 * the packets calling tcp_output() only once.
1518 		 * In the UDP case, send out the packets immediately.
1519 		 * Using a thread would make things slower.
1520 		 */
1521 		if (so->so_proto->pr_flags & PR_WANTRCVD)
1522 			task_add(sosplice_taskq, &so->so_splicetask);
1523 		else
1524 			somove(so, M_DONTWAIT);
1525 	}
1526 	if (isspliced(so))
1527 		return;
1528 #endif
1529 	sowakeup(so, &so->so_rcv);
1530 	if (so->so_upcall) {
1531 		(*(so->so_upcall))(so, so->so_upcallarg, M_DONTWAIT);
1532 	}
1533 }
1534 
1535 void
1536 sowwakeup(struct socket *so)
1537 {
1538 	NET_ASSERT_LOCKED();
1539 
1540 #ifdef SOCKET_SPLICE
1541 	if (so->so_snd.sb_flagsintr & SB_SPLICE)
1542 		task_add(sosplice_taskq, &so->so_sp->ssp_soback->so_splicetask);
1543 #endif
1544 	sowakeup(so, &so->so_snd);
1545 }
1546 
1547 int
1548 sosetopt(struct socket *so, int level, int optname, struct mbuf *m0)
1549 {
1550 	int s, error = 0;
1551 	struct mbuf *m = m0;
1552 
1553 	if (level != SOL_SOCKET) {
1554 		if (so->so_proto && so->so_proto->pr_ctloutput) {
1555 			NET_LOCK(s);
1556 			error = (*so->so_proto->pr_ctloutput)(PRCO_SETOPT, so,
1557 			    level, optname, &m0);
1558 			NET_UNLOCK(s);
1559 			return (error);
1560 		}
1561 		error = ENOPROTOOPT;
1562 	} else {
1563 		switch (optname) {
1564 		case SO_BINDANY:
1565 			if ((error = suser(curproc, 0)) != 0)	/* XXX */
1566 				goto bad;
1567 			break;
1568 		}
1569 
1570 		switch (optname) {
1571 
1572 		case SO_LINGER:
1573 			if (m == NULL || m->m_len != sizeof (struct linger) ||
1574 			    mtod(m, struct linger *)->l_linger < 0 ||
1575 			    mtod(m, struct linger *)->l_linger > SHRT_MAX) {
1576 				error = EINVAL;
1577 				goto bad;
1578 			}
1579 			so->so_linger = mtod(m, struct linger *)->l_linger;
1580 			/* FALLTHROUGH */
1581 
1582 		case SO_BINDANY:
1583 		case SO_DEBUG:
1584 		case SO_KEEPALIVE:
1585 		case SO_USELOOPBACK:
1586 		case SO_BROADCAST:
1587 		case SO_REUSEADDR:
1588 		case SO_REUSEPORT:
1589 		case SO_OOBINLINE:
1590 		case SO_TIMESTAMP:
1591 			if (m == NULL || m->m_len < sizeof (int)) {
1592 				error = EINVAL;
1593 				goto bad;
1594 			}
1595 			if (*mtod(m, int *))
1596 				so->so_options |= optname;
1597 			else
1598 				so->so_options &= ~optname;
1599 			break;
1600 
1601 		case SO_DONTROUTE:
1602 			if (m == NULL || m->m_len < sizeof (int)) {
1603 				error = EINVAL;
1604 				goto bad;
1605 			}
1606 			if (*mtod(m, int *))
1607 				error = EOPNOTSUPP;
1608 			break;
1609 
1610 		case SO_SNDBUF:
1611 		case SO_RCVBUF:
1612 		case SO_SNDLOWAT:
1613 		case SO_RCVLOWAT:
1614 		    {
1615 			u_long cnt;
1616 
1617 			if (m == NULL || m->m_len < sizeof (int)) {
1618 				error = EINVAL;
1619 				goto bad;
1620 			}
1621 			cnt = *mtod(m, int *);
1622 			if ((long)cnt <= 0)
1623 				cnt = 1;
1624 			switch (optname) {
1625 
1626 			case SO_SNDBUF:
1627 				if (so->so_state & SS_CANTSENDMORE) {
1628 					error = EINVAL;
1629 					goto bad;
1630 				}
1631 				if (sbcheckreserve(cnt, so->so_snd.sb_wat) ||
1632 				    sbreserve(&so->so_snd, cnt)) {
1633 					error = ENOBUFS;
1634 					goto bad;
1635 				}
1636 				so->so_snd.sb_wat = cnt;
1637 				break;
1638 
1639 			case SO_RCVBUF:
1640 				if (so->so_state & SS_CANTRCVMORE) {
1641 					error = EINVAL;
1642 					goto bad;
1643 				}
1644 				if (sbcheckreserve(cnt, so->so_rcv.sb_wat) ||
1645 				    sbreserve(&so->so_rcv, cnt)) {
1646 					error = ENOBUFS;
1647 					goto bad;
1648 				}
1649 				so->so_rcv.sb_wat = cnt;
1650 				break;
1651 
1652 			case SO_SNDLOWAT:
1653 				so->so_snd.sb_lowat =
1654 				    (cnt > so->so_snd.sb_hiwat) ?
1655 				    so->so_snd.sb_hiwat : cnt;
1656 				break;
1657 			case SO_RCVLOWAT:
1658 				so->so_rcv.sb_lowat =
1659 				    (cnt > so->so_rcv.sb_hiwat) ?
1660 				    so->so_rcv.sb_hiwat : cnt;
1661 				break;
1662 			}
1663 			break;
1664 		    }
1665 
1666 		case SO_SNDTIMEO:
1667 		case SO_RCVTIMEO:
1668 		    {
1669 			struct timeval tv;
1670 			int val;
1671 
1672 			if (m == NULL || m->m_len < sizeof (tv)) {
1673 				error = EINVAL;
1674 				goto bad;
1675 			}
1676 			memcpy(&tv, mtod(m, struct timeval *), sizeof tv);
1677 			val = tvtohz(&tv);
1678 			if (val > USHRT_MAX) {
1679 				error = EDOM;
1680 				goto bad;
1681 			}
1682 
1683 			switch (optname) {
1684 
1685 			case SO_SNDTIMEO:
1686 				so->so_snd.sb_timeo = val;
1687 				break;
1688 			case SO_RCVTIMEO:
1689 				so->so_rcv.sb_timeo = val;
1690 				break;
1691 			}
1692 			break;
1693 		    }
1694 
1695 		case SO_RTABLE:
1696 			if (so->so_proto && so->so_proto->pr_domain &&
1697 			    so->so_proto->pr_domain->dom_protosw &&
1698 			    so->so_proto->pr_ctloutput) {
1699 				struct domain *dom = so->so_proto->pr_domain;
1700 
1701 				level = dom->dom_protosw->pr_protocol;
1702 				NET_LOCK(s);
1703 				error = (*so->so_proto->pr_ctloutput)
1704 				    (PRCO_SETOPT, so, level, optname, &m0);
1705 				NET_UNLOCK(s);
1706 				return (error);
1707 			}
1708 			error = ENOPROTOOPT;
1709 			break;
1710 
1711 #ifdef SOCKET_SPLICE
1712 		case SO_SPLICE:
1713 			if (m == NULL) {
1714 				error = sosplice(so, -1, 0, NULL);
1715 			} else if (m->m_len < sizeof(int)) {
1716 				error = EINVAL;
1717 				goto bad;
1718 			} else if (m->m_len < sizeof(struct splice)) {
1719 				error = sosplice(so, *mtod(m, int *), 0, NULL);
1720 			} else {
1721 				error = sosplice(so,
1722 				    mtod(m, struct splice *)->sp_fd,
1723 				    mtod(m, struct splice *)->sp_max,
1724 				   &mtod(m, struct splice *)->sp_idle);
1725 			}
1726 			break;
1727 #endif /* SOCKET_SPLICE */
1728 
1729 		default:
1730 			error = ENOPROTOOPT;
1731 			break;
1732 		}
1733 		if (error == 0 && so->so_proto && so->so_proto->pr_ctloutput) {
1734 			NET_LOCK(s);
1735 			(*so->so_proto->pr_ctloutput)(PRCO_SETOPT, so,
1736 			    level, optname, &m0);
1737 			NET_UNLOCK(s);
1738 			m = NULL;	/* freed by protocol */
1739 		}
1740 	}
1741 bad:
1742 	if (m)
1743 		(void) m_free(m);
1744 	return (error);
1745 }
1746 
1747 int
1748 sogetopt(struct socket *so, int level, int optname, struct mbuf **mp)
1749 {
1750 	int s, error = 0;
1751 	struct mbuf *m;
1752 
1753 	if (level != SOL_SOCKET) {
1754 		if (so->so_proto && so->so_proto->pr_ctloutput) {
1755 			NET_LOCK(s);
1756 			error = (*so->so_proto->pr_ctloutput)(PRCO_GETOPT, so,
1757 			    level, optname, mp);
1758 			NET_UNLOCK(s);
1759 			return (error);
1760 		} else
1761 			return (ENOPROTOOPT);
1762 	} else {
1763 		m = m_get(M_WAIT, MT_SOOPTS);
1764 		m->m_len = sizeof (int);
1765 
1766 		switch (optname) {
1767 
1768 		case SO_LINGER:
1769 			m->m_len = sizeof (struct linger);
1770 			mtod(m, struct linger *)->l_onoff =
1771 				so->so_options & SO_LINGER;
1772 			mtod(m, struct linger *)->l_linger = so->so_linger;
1773 			break;
1774 
1775 		case SO_BINDANY:
1776 		case SO_USELOOPBACK:
1777 		case SO_DEBUG:
1778 		case SO_KEEPALIVE:
1779 		case SO_REUSEADDR:
1780 		case SO_REUSEPORT:
1781 		case SO_BROADCAST:
1782 		case SO_OOBINLINE:
1783 		case SO_TIMESTAMP:
1784 			*mtod(m, int *) = so->so_options & optname;
1785 			break;
1786 
1787 		case SO_DONTROUTE:
1788 			*mtod(m, int *) = 0;
1789 			break;
1790 
1791 		case SO_TYPE:
1792 			*mtod(m, int *) = so->so_type;
1793 			break;
1794 
1795 		case SO_ERROR:
1796 			*mtod(m, int *) = so->so_error;
1797 			so->so_error = 0;
1798 			break;
1799 
1800 		case SO_SNDBUF:
1801 			*mtod(m, int *) = so->so_snd.sb_hiwat;
1802 			break;
1803 
1804 		case SO_RCVBUF:
1805 			*mtod(m, int *) = so->so_rcv.sb_hiwat;
1806 			break;
1807 
1808 		case SO_SNDLOWAT:
1809 			*mtod(m, int *) = so->so_snd.sb_lowat;
1810 			break;
1811 
1812 		case SO_RCVLOWAT:
1813 			*mtod(m, int *) = so->so_rcv.sb_lowat;
1814 			break;
1815 
1816 		case SO_SNDTIMEO:
1817 		case SO_RCVTIMEO:
1818 		    {
1819 			struct timeval tv;
1820 			int val = (optname == SO_SNDTIMEO ?
1821 			    so->so_snd.sb_timeo : so->so_rcv.sb_timeo);
1822 
1823 			m->m_len = sizeof(struct timeval);
1824 			memset(&tv, 0, sizeof(tv));
1825 			tv.tv_sec = val / hz;
1826 			tv.tv_usec = (val % hz) * tick;
1827 			memcpy(mtod(m, struct timeval *), &tv, sizeof tv);
1828 			break;
1829 		    }
1830 
1831 		case SO_RTABLE:
1832 			(void)m_free(m);
1833 			if (so->so_proto && so->so_proto->pr_domain &&
1834 			    so->so_proto->pr_domain->dom_protosw &&
1835 			    so->so_proto->pr_ctloutput) {
1836 				struct domain *dom = so->so_proto->pr_domain;
1837 
1838 				level = dom->dom_protosw->pr_protocol;
1839 				NET_LOCK(s);
1840 				error = (*so->so_proto->pr_ctloutput)
1841 				    (PRCO_GETOPT, so, level, optname, mp);
1842 				NET_UNLOCK(s);
1843 				return (error);
1844 			}
1845 			return (ENOPROTOOPT);
1846 			break;
1847 
1848 #ifdef SOCKET_SPLICE
1849 		case SO_SPLICE:
1850 		    {
1851 			off_t len;
1852 			int s = splsoftnet();
1853 
1854 			m->m_len = sizeof(off_t);
1855 			len = so->so_sp ? so->so_sp->ssp_len : 0;
1856 			memcpy(mtod(m, off_t *), &len, sizeof(off_t));
1857 			splx(s);
1858 			break;
1859 		    }
1860 #endif /* SOCKET_SPLICE */
1861 
1862 		case SO_PEERCRED:
1863 			if (so->so_proto->pr_protocol == AF_UNIX) {
1864 				struct unpcb *unp = sotounpcb(so);
1865 
1866 				if (unp->unp_flags & UNP_FEIDS) {
1867 					m->m_len = sizeof(unp->unp_connid);
1868 					memcpy(mtod(m, caddr_t),
1869 					    &(unp->unp_connid), m->m_len);
1870 					break;
1871 				}
1872 				(void)m_free(m);
1873 				return (ENOTCONN);
1874 			}
1875 			(void)m_free(m);
1876 			return (EOPNOTSUPP);
1877 			break;
1878 
1879 		default:
1880 			(void)m_free(m);
1881 			return (ENOPROTOOPT);
1882 		}
1883 		*mp = m;
1884 		return (0);
1885 	}
1886 }
1887 
1888 void
1889 sohasoutofband(struct socket *so)
1890 {
1891 	csignal(so->so_pgid, SIGURG, so->so_siguid, so->so_sigeuid);
1892 	selwakeup(&so->so_rcv.sb_sel);
1893 }
1894 
1895 int
1896 soo_kqfilter(struct file *fp, struct knote *kn)
1897 {
1898 	struct socket *so = kn->kn_fp->f_data;
1899 	struct sockbuf *sb;
1900 
1901 	KERNEL_ASSERT_LOCKED();
1902 
1903 	switch (kn->kn_filter) {
1904 	case EVFILT_READ:
1905 		if (so->so_options & SO_ACCEPTCONN)
1906 			kn->kn_fop = &solisten_filtops;
1907 		else
1908 			kn->kn_fop = &soread_filtops;
1909 		sb = &so->so_rcv;
1910 		break;
1911 	case EVFILT_WRITE:
1912 		kn->kn_fop = &sowrite_filtops;
1913 		sb = &so->so_snd;
1914 		break;
1915 	default:
1916 		return (EINVAL);
1917 	}
1918 
1919 	SLIST_INSERT_HEAD(&sb->sb_sel.si_note, kn, kn_selnext);
1920 	sb->sb_flags |= SB_KNOTE;
1921 
1922 	return (0);
1923 }
1924 
1925 void
1926 filt_sordetach(struct knote *kn)
1927 {
1928 	struct socket *so = kn->kn_fp->f_data;
1929 
1930 	KERNEL_ASSERT_LOCKED();
1931 
1932 	SLIST_REMOVE(&so->so_rcv.sb_sel.si_note, kn, knote, kn_selnext);
1933 	if (SLIST_EMPTY(&so->so_rcv.sb_sel.si_note))
1934 		so->so_rcv.sb_flags &= ~SB_KNOTE;
1935 }
1936 
1937 int
1938 filt_soread(struct knote *kn, long hint)
1939 {
1940 	struct socket *so = kn->kn_fp->f_data;
1941 
1942 	kn->kn_data = so->so_rcv.sb_cc;
1943 #ifdef SOCKET_SPLICE
1944 	if (isspliced(so))
1945 		return (0);
1946 #endif /* SOCKET_SPLICE */
1947 	if (so->so_state & SS_CANTRCVMORE) {
1948 		kn->kn_flags |= EV_EOF;
1949 		kn->kn_fflags = so->so_error;
1950 		return (1);
1951 	}
1952 	if (so->so_error)	/* temporary udp error */
1953 		return (1);
1954 	if (kn->kn_sfflags & NOTE_LOWAT)
1955 		return (kn->kn_data >= kn->kn_sdata);
1956 	return (kn->kn_data >= so->so_rcv.sb_lowat);
1957 }
1958 
1959 void
1960 filt_sowdetach(struct knote *kn)
1961 {
1962 	struct socket *so = kn->kn_fp->f_data;
1963 
1964 	KERNEL_ASSERT_LOCKED();
1965 
1966 	SLIST_REMOVE(&so->so_snd.sb_sel.si_note, kn, knote, kn_selnext);
1967 	if (SLIST_EMPTY(&so->so_snd.sb_sel.si_note))
1968 		so->so_snd.sb_flags &= ~SB_KNOTE;
1969 }
1970 
1971 int
1972 filt_sowrite(struct knote *kn, long hint)
1973 {
1974 	struct socket *so = kn->kn_fp->f_data;
1975 
1976 	kn->kn_data = sbspace(&so->so_snd);
1977 	if (so->so_state & SS_CANTSENDMORE) {
1978 		kn->kn_flags |= EV_EOF;
1979 		kn->kn_fflags = so->so_error;
1980 		return (1);
1981 	}
1982 	if (so->so_error)	/* temporary udp error */
1983 		return (1);
1984 	if (((so->so_state & SS_ISCONNECTED) == 0) &&
1985 	    (so->so_proto->pr_flags & PR_CONNREQUIRED))
1986 		return (0);
1987 	if (kn->kn_sfflags & NOTE_LOWAT)
1988 		return (kn->kn_data >= kn->kn_sdata);
1989 	return (kn->kn_data >= so->so_snd.sb_lowat);
1990 }
1991 
1992 int
1993 filt_solisten(struct knote *kn, long hint)
1994 {
1995 	struct socket *so = kn->kn_fp->f_data;
1996 
1997 	kn->kn_data = so->so_qlen;
1998 	return (so->so_qlen != 0);
1999 }
2000 
2001 #ifdef DDB
2002 void
2003 sobuf_print(struct sockbuf *,
2004     int (*)(const char *, ...) __attribute__((__format__(__kprintf__,1,2))));
2005 
2006 void
2007 sobuf_print(struct sockbuf *sb,
2008     int (*pr)(const char *, ...) __attribute__((__format__(__kprintf__,1,2))))
2009 {
2010 	(*pr)("\tsb_cc: %lu\n", sb->sb_cc);
2011 	(*pr)("\tsb_datacc: %lu\n", sb->sb_datacc);
2012 	(*pr)("\tsb_hiwat: %lu\n", sb->sb_hiwat);
2013 	(*pr)("\tsb_wat: %lu\n", sb->sb_wat);
2014 	(*pr)("\tsb_mbcnt: %lu\n", sb->sb_mbcnt);
2015 	(*pr)("\tsb_mbmax: %lu\n", sb->sb_mbmax);
2016 	(*pr)("\tsb_lowat: %ld\n", sb->sb_lowat);
2017 	(*pr)("\tsb_mb: %p\n", sb->sb_mb);
2018 	(*pr)("\tsb_mbtail: %p\n", sb->sb_mbtail);
2019 	(*pr)("\tsb_lastrecord: %p\n", sb->sb_lastrecord);
2020 	(*pr)("\tsb_sel: ...\n");
2021 	(*pr)("\tsb_flagsintr: %d\n", sb->sb_flagsintr);
2022 	(*pr)("\tsb_flags: %i\n", sb->sb_flags);
2023 	(*pr)("\tsb_timeo: %i\n", sb->sb_timeo);
2024 }
2025 
2026 void
2027 so_print(void *v,
2028     int (*pr)(const char *, ...) __attribute__((__format__(__kprintf__,1,2))))
2029 {
2030 	struct socket *so = v;
2031 
2032 	(*pr)("socket %p\n", so);
2033 	(*pr)("so_type: %i\n", so->so_type);
2034 	(*pr)("so_options: 0x%04x\n", so->so_options); /* %b */
2035 	(*pr)("so_linger: %i\n", so->so_linger);
2036 	(*pr)("so_state: %i\n", so->so_state);
2037 	(*pr)("so_pcb: %p\n", so->so_pcb);
2038 	(*pr)("so_proto: %p\n", so->so_proto);
2039 
2040 	(*pr)("so_head: %p\n", so->so_head);
2041 	(*pr)("so_onq: %p\n", so->so_onq);
2042 	(*pr)("so_q0: @%p first: %p\n", &so->so_q0, TAILQ_FIRST(&so->so_q0));
2043 	(*pr)("so_q: @%p first: %p\n", &so->so_q, TAILQ_FIRST(&so->so_q));
2044 	(*pr)("so_eq: next: %p\n", TAILQ_NEXT(so, so_qe));
2045 	(*pr)("so_q0len: %i\n", so->so_q0len);
2046 	(*pr)("so_qlen: %i\n", so->so_qlen);
2047 	(*pr)("so_qlimit: %i\n", so->so_qlimit);
2048 	(*pr)("so_timeo: %i\n", so->so_timeo);
2049 	(*pr)("so_pgid: %i\n", so->so_pgid);
2050 	(*pr)("so_siguid: %i\n", so->so_siguid);
2051 	(*pr)("so_sigeuid: %i\n", so->so_sigeuid);
2052 	(*pr)("so_obmark: %lu\n", so->so_oobmark);
2053 
2054 	(*pr)("so_sp: %p\n", so->so_sp);
2055 	if (so->so_sp != NULL) {
2056 		(*pr)("\tssp_socket: %p\n", so->so_sp->ssp_socket);
2057 		(*pr)("\tssp_soback: %p\n", so->so_sp->ssp_soback);
2058 		(*pr)("\tssp_len: %lld\n",
2059 		    (unsigned long long)so->so_sp->ssp_len);
2060 		(*pr)("\tssp_max: %lld\n",
2061 		    (unsigned long long)so->so_sp->ssp_max);
2062 		(*pr)("\tssp_idletv: %lld %ld\n", so->so_sp->ssp_idletv.tv_sec,
2063 		    so->so_sp->ssp_idletv.tv_usec);
2064 		(*pr)("\tssp_idleto: %spending (@%i)\n",
2065 		    timeout_pending(&so->so_sp->ssp_idleto) ? "" : "not ",
2066 		    so->so_sp->ssp_idleto.to_time);
2067 	}
2068 
2069 	(*pr)("so_rcv:\n");
2070 	sobuf_print(&so->so_rcv, pr);
2071 	(*pr)("so_snd:\n");
2072 	sobuf_print(&so->so_snd, pr);
2073 
2074 	(*pr)("so_upcall: %p so_upcallarg: %p\n",
2075 	    so->so_upcall, so->so_upcallarg);
2076 
2077 	(*pr)("so_euid: %d so_ruid: %d\n", so->so_euid, so->so_ruid);
2078 	(*pr)("so_egid: %d so_rgid: %d\n", so->so_egid, so->so_rgid);
2079 	(*pr)("so_cpid: %d\n", so->so_cpid);
2080 }
2081 #endif
2082 
2083