xref: /freebsd/sys/kern/uipc_socket.c (revision 52ec752989b2e6d4e9a59a8ff25d8ff596d85e62)
1 /*
2  * Copyright (c) 1982, 1986, 1988, 1990, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  *	@(#)uipc_socket.c	8.3 (Berkeley) 4/15/94
34  */
35 
36 #include <sys/cdefs.h>
37 __FBSDID("$FreeBSD$");
38 
39 #include "opt_inet.h"
40 #include "opt_mac.h"
41 #include "opt_zero.h"
42 
43 #include <sys/param.h>
44 #include <sys/systm.h>
45 #include <sys/fcntl.h>
46 #include <sys/limits.h>
47 #include <sys/lock.h>
48 #include <sys/mac.h>
49 #include <sys/malloc.h>
50 #include <sys/mbuf.h>
51 #include <sys/mutex.h>
52 #include <sys/domain.h>
53 #include <sys/file.h>			/* for struct knote */
54 #include <sys/kernel.h>
55 #include <sys/event.h>
56 #include <sys/poll.h>
57 #include <sys/proc.h>
58 #include <sys/protosw.h>
59 #include <sys/socket.h>
60 #include <sys/socketvar.h>
61 #include <sys/resourcevar.h>
62 #include <sys/signalvar.h>
63 #include <sys/sysctl.h>
64 #include <sys/uio.h>
65 #include <sys/jail.h>
66 
67 #include <vm/uma.h>
68 
69 
70 #ifdef INET
71 static int	 do_setopt_accept_filter(struct socket *so, struct sockopt *sopt);
72 #endif
73 
74 static void	filt_sordetach(struct knote *kn);
75 static int	filt_soread(struct knote *kn, long hint);
76 static void	filt_sowdetach(struct knote *kn);
77 static int	filt_sowrite(struct knote *kn, long hint);
78 static int	filt_solisten(struct knote *kn, long hint);
79 
80 static struct filterops solisten_filtops =
81 	{ 1, NULL, filt_sordetach, filt_solisten };
82 static struct filterops soread_filtops =
83 	{ 1, NULL, filt_sordetach, filt_soread };
84 static struct filterops sowrite_filtops =
85 	{ 1, NULL, filt_sowdetach, filt_sowrite };
86 
87 uma_zone_t socket_zone;
88 so_gen_t	so_gencnt;	/* generation count for sockets */
89 
90 MALLOC_DEFINE(M_SONAME, "soname", "socket name");
91 MALLOC_DEFINE(M_PCB, "pcb", "protocol control block");
92 
93 SYSCTL_DECL(_kern_ipc);
94 
95 static int somaxconn = SOMAXCONN;
96 SYSCTL_INT(_kern_ipc, KIPC_SOMAXCONN, somaxconn, CTLFLAG_RW,
97     &somaxconn, 0, "Maximum pending socket connection queue size");
98 static int numopensockets;
99 SYSCTL_INT(_kern_ipc, OID_AUTO, numopensockets, CTLFLAG_RD,
100     &numopensockets, 0, "Number of open sockets");
101 #ifdef ZERO_COPY_SOCKETS
102 /* These aren't static because they're used in other files. */
103 int so_zero_copy_send = 1;
104 int so_zero_copy_receive = 1;
105 SYSCTL_NODE(_kern_ipc, OID_AUTO, zero_copy, CTLFLAG_RD, 0,
106     "Zero copy controls");
107 SYSCTL_INT(_kern_ipc_zero_copy, OID_AUTO, receive, CTLFLAG_RW,
108     &so_zero_copy_receive, 0, "Enable zero copy receive");
109 SYSCTL_INT(_kern_ipc_zero_copy, OID_AUTO, send, CTLFLAG_RW,
110     &so_zero_copy_send, 0, "Enable zero copy send");
111 #endif /* ZERO_COPY_SOCKETS */
112 
113 
114 /*
115  * Socket operation routines.
116  * These routines are called by the routines in
117  * sys_socket.c or from a system process, and
118  * implement the semantics of socket operations by
119  * switching out to the protocol specific routines.
120  */
121 
122 /*
123  * Get a socket structure from our zone, and initialize it.
124  * Note that it would probably be better to allocate socket
125  * and PCB at the same time, but I'm not convinced that all
126  * the protocols can be easily modified to do this.
127  *
128  * soalloc() returns a socket with a ref count of 0.
129  */
130 struct socket *
131 soalloc(waitok)
132 	int waitok;
133 {
134 	struct socket *so;
135 #ifdef MAC
136 	int error;
137 #endif
138 	int flag;
139 
140 	if (waitok == 1)
141 		flag = M_WAITOK;
142 	else
143 		flag = M_NOWAIT;
144 	flag |= M_ZERO;
145 	so = uma_zalloc(socket_zone, flag);
146 	if (so) {
147 #ifdef MAC
148 		error = mac_init_socket(so, flag);
149 		if (error != 0) {
150 			uma_zfree(socket_zone, so);
151 			so = NULL;
152 			return so;
153 		}
154 #endif
155 		/* XXX race condition for reentrant kernel */
156 		so->so_gencnt = ++so_gencnt;
157 		/* sx_init(&so->so_sxlock, "socket sxlock"); */
158 		TAILQ_INIT(&so->so_aiojobq);
159 		++numopensockets;
160 	}
161 	return so;
162 }
163 
164 /*
165  * socreate returns a socket with a ref count of 1.  The socket should be
166  * closed with soclose().
167  */
168 int
169 socreate(dom, aso, type, proto, cred, td)
170 	int dom;
171 	struct socket **aso;
172 	int type;
173 	int proto;
174 	struct ucred *cred;
175 	struct thread *td;
176 {
177 	struct protosw *prp;
178 	struct socket *so;
179 	int error;
180 
181 	if (proto)
182 		prp = pffindproto(dom, proto, type);
183 	else
184 		prp = pffindtype(dom, type);
185 
186 	if (prp == 0 || prp->pr_usrreqs->pru_attach == 0)
187 		return (EPROTONOSUPPORT);
188 
189 	if (jailed(cred) && jail_socket_unixiproute_only &&
190 	    prp->pr_domain->dom_family != PF_LOCAL &&
191 	    prp->pr_domain->dom_family != PF_INET &&
192 	    prp->pr_domain->dom_family != PF_ROUTE) {
193 		return (EPROTONOSUPPORT);
194 	}
195 
196 	if (prp->pr_type != type)
197 		return (EPROTOTYPE);
198 	so = soalloc(1);
199 	if (so == NULL)
200 		return (ENOBUFS);
201 
202 	TAILQ_INIT(&so->so_incomp);
203 	TAILQ_INIT(&so->so_comp);
204 	so->so_type = type;
205 	so->so_cred = crhold(cred);
206 	so->so_proto = prp;
207 #ifdef MAC
208 	mac_create_socket(cred, so);
209 #endif
210 	soref(so);
211 	error = (*prp->pr_usrreqs->pru_attach)(so, proto, td);
212 	if (error) {
213 		so->so_state |= SS_NOFDREF;
214 		sorele(so);
215 		return (error);
216 	}
217 	*aso = so;
218 	return (0);
219 }
220 
221 int
222 sobind(so, nam, td)
223 	struct socket *so;
224 	struct sockaddr *nam;
225 	struct thread *td;
226 {
227 	int s = splnet();
228 	int error;
229 
230 	error = (*so->so_proto->pr_usrreqs->pru_bind)(so, nam, td);
231 	splx(s);
232 	return (error);
233 }
234 
235 void
236 sodealloc(struct socket *so)
237 {
238 
239 	KASSERT(so->so_count == 0, ("sodealloc(): so_count %d", so->so_count));
240 	so->so_gencnt = ++so_gencnt;
241 	if (so->so_rcv.sb_hiwat)
242 		(void)chgsbsize(so->so_cred->cr_uidinfo,
243 		    &so->so_rcv.sb_hiwat, 0, RLIM_INFINITY);
244 	if (so->so_snd.sb_hiwat)
245 		(void)chgsbsize(so->so_cred->cr_uidinfo,
246 		    &so->so_snd.sb_hiwat, 0, RLIM_INFINITY);
247 #ifdef INET
248 	/* remove acccept filter if one is present. */
249 	if (so->so_accf != NULL)
250 		do_setopt_accept_filter(so, NULL);
251 #endif
252 #ifdef MAC
253 	mac_destroy_socket(so);
254 #endif
255 	crfree(so->so_cred);
256 	/* sx_destroy(&so->so_sxlock); */
257 	uma_zfree(socket_zone, so);
258 	--numopensockets;
259 }
260 
261 int
262 solisten(so, backlog, td)
263 	struct socket *so;
264 	int backlog;
265 	struct thread *td;
266 {
267 	int s, error;
268 
269 	s = splnet();
270 	if (so->so_state & (SS_ISCONNECTED | SS_ISCONNECTING |
271 			    SS_ISDISCONNECTING)) {
272 		splx(s);
273 		return (EINVAL);
274 	}
275 	error = (*so->so_proto->pr_usrreqs->pru_listen)(so, td);
276 	if (error) {
277 		splx(s);
278 		return (error);
279 	}
280 	if (TAILQ_EMPTY(&so->so_comp))
281 		so->so_options |= SO_ACCEPTCONN;
282 	if (backlog < 0 || backlog > somaxconn)
283 		backlog = somaxconn;
284 	so->so_qlimit = backlog;
285 	splx(s);
286 	return (0);
287 }
288 
289 void
290 sofree(so)
291 	struct socket *so;
292 {
293 	struct socket *head = so->so_head;
294 
295 	KASSERT(so->so_count == 0, ("socket %p so_count not 0", so));
296 
297 	if (so->so_pcb || (so->so_state & SS_NOFDREF) == 0)
298 		return;
299 	if (head != NULL) {
300 		if (so->so_state & SS_INCOMP) {
301 			TAILQ_REMOVE(&head->so_incomp, so, so_list);
302 			head->so_incqlen--;
303 		} else if (so->so_state & SS_COMP) {
304 			/*
305 			 * We must not decommission a socket that's
306 			 * on the accept(2) queue.  If we do, then
307 			 * accept(2) may hang after select(2) indicated
308 			 * that the listening socket was ready.
309 			 */
310 			return;
311 		} else {
312 			panic("sofree: not queued");
313 		}
314 		so->so_state &= ~SS_INCOMP;
315 		so->so_head = NULL;
316 	}
317 	sbrelease(&so->so_snd, so);
318 	sorflush(so);
319 	sodealloc(so);
320 }
321 
322 /*
323  * Close a socket on last file table reference removal.
324  * Initiate disconnect if connected.
325  * Free socket when disconnect complete.
326  *
327  * This function will sorele() the socket.  Note that soclose() may be
328  * called prior to the ref count reaching zero.  The actual socket
329  * structure will not be freed until the ref count reaches zero.
330  */
331 int
332 soclose(so)
333 	struct socket *so;
334 {
335 	int s = splnet();		/* conservative */
336 	int error = 0;
337 
338 	funsetown(&so->so_sigio);
339 	if (so->so_options & SO_ACCEPTCONN) {
340 		struct socket *sp, *sonext;
341 
342 		sp = TAILQ_FIRST(&so->so_incomp);
343 		for (; sp != NULL; sp = sonext) {
344 			sonext = TAILQ_NEXT(sp, so_list);
345 			(void) soabort(sp);
346 		}
347 		for (sp = TAILQ_FIRST(&so->so_comp); sp != NULL; sp = sonext) {
348 			sonext = TAILQ_NEXT(sp, so_list);
349 			/* Dequeue from so_comp since sofree() won't do it */
350 			TAILQ_REMOVE(&so->so_comp, sp, so_list);
351 			so->so_qlen--;
352 			sp->so_state &= ~SS_COMP;
353 			sp->so_head = NULL;
354 			(void) soabort(sp);
355 		}
356 	}
357 	if (so->so_pcb == 0)
358 		goto discard;
359 	if (so->so_state & SS_ISCONNECTED) {
360 		if ((so->so_state & SS_ISDISCONNECTING) == 0) {
361 			error = sodisconnect(so);
362 			if (error)
363 				goto drop;
364 		}
365 		if (so->so_options & SO_LINGER) {
366 			if ((so->so_state & SS_ISDISCONNECTING) &&
367 			    (so->so_state & SS_NBIO))
368 				goto drop;
369 			while (so->so_state & SS_ISCONNECTED) {
370 				error = tsleep(&so->so_timeo,
371 				    PSOCK | PCATCH, "soclos", so->so_linger * hz);
372 				if (error)
373 					break;
374 			}
375 		}
376 	}
377 drop:
378 	if (so->so_pcb) {
379 		int error2 = (*so->so_proto->pr_usrreqs->pru_detach)(so);
380 		if (error == 0)
381 			error = error2;
382 	}
383 discard:
384 	if (so->so_state & SS_NOFDREF)
385 		panic("soclose: NOFDREF");
386 	so->so_state |= SS_NOFDREF;
387 	sorele(so);
388 	splx(s);
389 	return (error);
390 }
391 
392 /*
393  * Must be called at splnet...
394  */
395 int
396 soabort(so)
397 	struct socket *so;
398 {
399 	int error;
400 
401 	error = (*so->so_proto->pr_usrreqs->pru_abort)(so);
402 	if (error) {
403 		sotryfree(so);	/* note: does not decrement the ref count */
404 		return error;
405 	}
406 	return (0);
407 }
408 
409 int
410 soaccept(so, nam)
411 	struct socket *so;
412 	struct sockaddr **nam;
413 {
414 	int s = splnet();
415 	int error;
416 
417 	if ((so->so_state & SS_NOFDREF) == 0)
418 		panic("soaccept: !NOFDREF");
419 	so->so_state &= ~SS_NOFDREF;
420 	error = (*so->so_proto->pr_usrreqs->pru_accept)(so, nam);
421 	splx(s);
422 	return (error);
423 }
424 
425 int
426 soconnect(so, nam, td)
427 	struct socket *so;
428 	struct sockaddr *nam;
429 	struct thread *td;
430 {
431 	int s;
432 	int error;
433 
434 	if (so->so_options & SO_ACCEPTCONN)
435 		return (EOPNOTSUPP);
436 	s = splnet();
437 	/*
438 	 * If protocol is connection-based, can only connect once.
439 	 * Otherwise, if connected, try to disconnect first.
440 	 * This allows user to disconnect by connecting to, e.g.,
441 	 * a null address.
442 	 */
443 	if (so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING) &&
444 	    ((so->so_proto->pr_flags & PR_CONNREQUIRED) ||
445 	    (error = sodisconnect(so))))
446 		error = EISCONN;
447 	else
448 		error = (*so->so_proto->pr_usrreqs->pru_connect)(so, nam, td);
449 	splx(s);
450 	return (error);
451 }
452 
453 int
454 soconnect2(so1, so2)
455 	struct socket *so1;
456 	struct socket *so2;
457 {
458 	int s = splnet();
459 	int error;
460 
461 	error = (*so1->so_proto->pr_usrreqs->pru_connect2)(so1, so2);
462 	splx(s);
463 	return (error);
464 }
465 
466 int
467 sodisconnect(so)
468 	struct socket *so;
469 {
470 	int s = splnet();
471 	int error;
472 
473 	if ((so->so_state & SS_ISCONNECTED) == 0) {
474 		error = ENOTCONN;
475 		goto bad;
476 	}
477 	if (so->so_state & SS_ISDISCONNECTING) {
478 		error = EALREADY;
479 		goto bad;
480 	}
481 	error = (*so->so_proto->pr_usrreqs->pru_disconnect)(so);
482 bad:
483 	splx(s);
484 	return (error);
485 }
486 
487 #define	SBLOCKWAIT(f)	(((f) & MSG_DONTWAIT) ? M_NOWAIT : M_WAITOK)
488 /*
489  * Send on a socket.
490  * If send must go all at once and message is larger than
491  * send buffering, then hard error.
492  * Lock against other senders.
493  * If must go all at once and not enough room now, then
494  * inform user that this would block and do nothing.
495  * Otherwise, if nonblocking, send as much as possible.
496  * The data to be sent is described by "uio" if nonzero,
497  * otherwise by the mbuf chain "top" (which must be null
498  * if uio is not).  Data provided in mbuf chain must be small
499  * enough to send all at once.
500  *
501  * Returns nonzero on error, timeout or signal; callers
502  * must check for short counts if EINTR/ERESTART are returned.
503  * Data and control buffers are freed on return.
504  */
505 
506 #ifdef ZERO_COPY_SOCKETS
507 struct so_zerocopy_stats{
508 	int size_ok;
509 	int align_ok;
510 	int found_ifp;
511 };
512 struct so_zerocopy_stats so_zerocp_stats = {0,0,0};
513 #include <netinet/in.h>
514 #include <net/route.h>
515 #include <netinet/in_pcb.h>
516 #include <vm/vm.h>
517 #include <vm/vm_page.h>
518 #include <vm/vm_object.h>
519 #endif /*ZERO_COPY_SOCKETS*/
520 
521 int
522 sosend(so, addr, uio, top, control, flags, td)
523 	struct socket *so;
524 	struct sockaddr *addr;
525 	struct uio *uio;
526 	struct mbuf *top;
527 	struct mbuf *control;
528 	int flags;
529 	struct thread *td;
530 {
531 	struct mbuf **mp;
532 	struct mbuf *m;
533 	long space, len, resid;
534 	int clen = 0, error, s, dontroute, mlen;
535 	int atomic = sosendallatonce(so) || top;
536 #ifdef ZERO_COPY_SOCKETS
537 	int cow_send;
538 #endif /* ZERO_COPY_SOCKETS */
539 
540 	if (uio)
541 		resid = uio->uio_resid;
542 	else
543 		resid = top->m_pkthdr.len;
544 	/*
545 	 * In theory resid should be unsigned.
546 	 * However, space must be signed, as it might be less than 0
547 	 * if we over-committed, and we must use a signed comparison
548 	 * of space and resid.  On the other hand, a negative resid
549 	 * causes us to loop sending 0-length segments to the protocol.
550 	 *
551 	 * Also check to make sure that MSG_EOR isn't used on SOCK_STREAM
552 	 * type sockets since that's an error.
553 	 */
554 	if (resid < 0 || (so->so_type == SOCK_STREAM && (flags & MSG_EOR))) {
555 		error = EINVAL;
556 		goto out;
557 	}
558 
559 	dontroute =
560 	    (flags & MSG_DONTROUTE) && (so->so_options & SO_DONTROUTE) == 0 &&
561 	    (so->so_proto->pr_flags & PR_ATOMIC);
562 	if (td)
563 		td->td_proc->p_stats->p_ru.ru_msgsnd++;
564 	if (control)
565 		clen = control->m_len;
566 #define	snderr(errno)	{ error = (errno); splx(s); goto release; }
567 
568 restart:
569 	error = sblock(&so->so_snd, SBLOCKWAIT(flags));
570 	if (error)
571 		goto out;
572 	do {
573 		s = splnet();
574 		if (so->so_state & SS_CANTSENDMORE)
575 			snderr(EPIPE);
576 		if (so->so_error) {
577 			error = so->so_error;
578 			so->so_error = 0;
579 			splx(s);
580 			goto release;
581 		}
582 		if ((so->so_state & SS_ISCONNECTED) == 0) {
583 			/*
584 			 * `sendto' and `sendmsg' is allowed on a connection-
585 			 * based socket if it supports implied connect.
586 			 * Return ENOTCONN if not connected and no address is
587 			 * supplied.
588 			 */
589 			if ((so->so_proto->pr_flags & PR_CONNREQUIRED) &&
590 			    (so->so_proto->pr_flags & PR_IMPLOPCL) == 0) {
591 				if ((so->so_state & SS_ISCONFIRMING) == 0 &&
592 				    !(resid == 0 && clen != 0))
593 					snderr(ENOTCONN);
594 			} else if (addr == 0)
595 			    snderr(so->so_proto->pr_flags & PR_CONNREQUIRED ?
596 				   ENOTCONN : EDESTADDRREQ);
597 		}
598 		space = sbspace(&so->so_snd);
599 		if (flags & MSG_OOB)
600 			space += 1024;
601 		if ((atomic && resid > so->so_snd.sb_hiwat) ||
602 		    clen > so->so_snd.sb_hiwat)
603 			snderr(EMSGSIZE);
604 		if (space < resid + clen &&
605 		    (atomic || space < so->so_snd.sb_lowat || space < clen)) {
606 			if (so->so_state & SS_NBIO)
607 				snderr(EWOULDBLOCK);
608 			sbunlock(&so->so_snd);
609 			error = sbwait(&so->so_snd);
610 			splx(s);
611 			if (error)
612 				goto out;
613 			goto restart;
614 		}
615 		splx(s);
616 		mp = &top;
617 		space -= clen;
618 		do {
619 		    if (uio == NULL) {
620 			/*
621 			 * Data is prepackaged in "top".
622 			 */
623 			resid = 0;
624 			if (flags & MSG_EOR)
625 				top->m_flags |= M_EOR;
626 		    } else do {
627 #ifdef ZERO_COPY_SOCKETS
628 			cow_send = 0;
629 #endif /* ZERO_COPY_SOCKETS */
630 			if (top == 0) {
631 				MGETHDR(m, M_TRYWAIT, MT_DATA);
632 				if (m == NULL) {
633 					error = ENOBUFS;
634 					goto release;
635 				}
636 				mlen = MHLEN;
637 				m->m_pkthdr.len = 0;
638 				m->m_pkthdr.rcvif = (struct ifnet *)0;
639 			} else {
640 				MGET(m, M_TRYWAIT, MT_DATA);
641 				if (m == NULL) {
642 					error = ENOBUFS;
643 					goto release;
644 				}
645 				mlen = MLEN;
646 			}
647 			if (resid >= MINCLSIZE) {
648 #ifdef ZERO_COPY_SOCKETS
649 				if (so_zero_copy_send &&
650 				    resid>=PAGE_SIZE &&
651 				    space>=PAGE_SIZE &&
652 				    uio->uio_iov->iov_len>=PAGE_SIZE) {
653 					so_zerocp_stats.size_ok++;
654 					if (!((vm_offset_t)
655 					  uio->uio_iov->iov_base & PAGE_MASK)){
656 						so_zerocp_stats.align_ok++;
657 						cow_send = socow_setup(m, uio);
658 					}
659 				}
660 				if (!cow_send){
661 #endif /* ZERO_COPY_SOCKETS */
662 				MCLGET(m, M_TRYWAIT);
663 				if ((m->m_flags & M_EXT) == 0)
664 					goto nopages;
665 				mlen = MCLBYTES;
666 				len = min(min(mlen, resid), space);
667 			} else {
668 #ifdef ZERO_COPY_SOCKETS
669 					len = PAGE_SIZE;
670 				}
671 
672 			} else {
673 #endif /* ZERO_COPY_SOCKETS */
674 nopages:
675 				len = min(min(mlen, resid), space);
676 				/*
677 				 * For datagram protocols, leave room
678 				 * for protocol headers in first mbuf.
679 				 */
680 				if (atomic && top == 0 && len < mlen)
681 					MH_ALIGN(m, len);
682 			}
683 			space -= len;
684 #ifdef ZERO_COPY_SOCKETS
685 			if (cow_send)
686 				error = 0;
687 			else
688 #endif /* ZERO_COPY_SOCKETS */
689 			error = uiomove(mtod(m, void *), (int)len, uio);
690 			resid = uio->uio_resid;
691 			m->m_len = len;
692 			*mp = m;
693 			top->m_pkthdr.len += len;
694 			if (error)
695 				goto release;
696 			mp = &m->m_next;
697 			if (resid <= 0) {
698 				if (flags & MSG_EOR)
699 					top->m_flags |= M_EOR;
700 				break;
701 			}
702 		    } while (space > 0 && atomic);
703 		    if (dontroute)
704 			    so->so_options |= SO_DONTROUTE;
705 		    s = splnet();				/* XXX */
706 		    /*
707 		     * XXX all the SS_CANTSENDMORE checks previously
708 		     * done could be out of date.  We could have recieved
709 		     * a reset packet in an interrupt or maybe we slept
710 		     * while doing page faults in uiomove() etc. We could
711 		     * probably recheck again inside the splnet() protection
712 		     * here, but there are probably other places that this
713 		     * also happens.  We must rethink this.
714 		     */
715 		    error = (*so->so_proto->pr_usrreqs->pru_send)(so,
716 			(flags & MSG_OOB) ? PRUS_OOB :
717 			/*
718 			 * If the user set MSG_EOF, the protocol
719 			 * understands this flag and nothing left to
720 			 * send then use PRU_SEND_EOF instead of PRU_SEND.
721 			 */
722 			((flags & MSG_EOF) &&
723 			 (so->so_proto->pr_flags & PR_IMPLOPCL) &&
724 			 (resid <= 0)) ?
725 				PRUS_EOF :
726 			/* If there is more to send set PRUS_MORETOCOME */
727 			(resid > 0 && space > 0) ? PRUS_MORETOCOME : 0,
728 			top, addr, control, td);
729 		    splx(s);
730 		    if (dontroute)
731 			    so->so_options &= ~SO_DONTROUTE;
732 		    clen = 0;
733 		    control = 0;
734 		    top = 0;
735 		    mp = &top;
736 		    if (error)
737 			goto release;
738 		} while (resid && space > 0);
739 	} while (resid);
740 
741 release:
742 	sbunlock(&so->so_snd);
743 out:
744 	if (top)
745 		m_freem(top);
746 	if (control)
747 		m_freem(control);
748 	return (error);
749 }
750 
751 /*
752  * Implement receive operations on a socket.
753  * We depend on the way that records are added to the sockbuf
754  * by sbappend*.  In particular, each record (mbufs linked through m_next)
755  * must begin with an address if the protocol so specifies,
756  * followed by an optional mbuf or mbufs containing ancillary data,
757  * and then zero or more mbufs of data.
758  * In order to avoid blocking network interrupts for the entire time here,
759  * we splx() while doing the actual copy to user space.
760  * Although the sockbuf is locked, new data may still be appended,
761  * and thus we must maintain consistency of the sockbuf during that time.
762  *
763  * The caller may receive the data as a single mbuf chain by supplying
764  * an mbuf **mp0 for use in returning the chain.  The uio is then used
765  * only for the count in uio_resid.
766  */
767 int
768 soreceive(so, psa, uio, mp0, controlp, flagsp)
769 	struct socket *so;
770 	struct sockaddr **psa;
771 	struct uio *uio;
772 	struct mbuf **mp0;
773 	struct mbuf **controlp;
774 	int *flagsp;
775 {
776 	struct mbuf *m, **mp;
777 	int flags, len, error, s, offset;
778 	struct protosw *pr = so->so_proto;
779 	struct mbuf *nextrecord;
780 	int moff, type = 0;
781 	int orig_resid = uio->uio_resid;
782 
783 	mp = mp0;
784 	if (psa)
785 		*psa = 0;
786 	if (controlp)
787 		*controlp = 0;
788 	if (flagsp)
789 		flags = *flagsp &~ MSG_EOR;
790 	else
791 		flags = 0;
792 	if (flags & MSG_OOB) {
793 		m = m_get(M_TRYWAIT, MT_DATA);
794 		if (m == NULL)
795 			return (ENOBUFS);
796 		error = (*pr->pr_usrreqs->pru_rcvoob)(so, m, flags & MSG_PEEK);
797 		if (error)
798 			goto bad;
799 		do {
800 #ifdef ZERO_COPY_SOCKETS
801 			if (so_zero_copy_receive) {
802 				vm_page_t pg;
803 				int disposable;
804 
805 				if ((m->m_flags & M_EXT)
806 				 && (m->m_ext.ext_type == EXT_DISPOSABLE))
807 					disposable = 1;
808 				else
809 					disposable = 0;
810 
811 				pg = PHYS_TO_VM_PAGE(vtophys(mtod(m, caddr_t)));
812 				if (uio->uio_offset == -1)
813 					uio->uio_offset =IDX_TO_OFF(pg->pindex);
814 
815 				error = uiomoveco(mtod(m, void *),
816 						  min(uio->uio_resid, m->m_len),
817 						  uio, pg->object,
818 						  disposable);
819 			} else
820 #endif /* ZERO_COPY_SOCKETS */
821 			error = uiomove(mtod(m, void *),
822 			    (int) min(uio->uio_resid, m->m_len), uio);
823 			m = m_free(m);
824 		} while (uio->uio_resid && error == 0 && m);
825 bad:
826 		if (m)
827 			m_freem(m);
828 		return (error);
829 	}
830 	if (mp)
831 		*mp = (struct mbuf *)0;
832 	if (so->so_state & SS_ISCONFIRMING && uio->uio_resid)
833 		(*pr->pr_usrreqs->pru_rcvd)(so, 0);
834 
835 restart:
836 	error = sblock(&so->so_rcv, SBLOCKWAIT(flags));
837 	if (error)
838 		return (error);
839 	s = splnet();
840 
841 	m = so->so_rcv.sb_mb;
842 	/*
843 	 * If we have less data than requested, block awaiting more
844 	 * (subject to any timeout) if:
845 	 *   1. the current count is less than the low water mark, or
846 	 *   2. MSG_WAITALL is set, and it is possible to do the entire
847 	 *	receive operation at once if we block (resid <= hiwat).
848 	 *   3. MSG_DONTWAIT is not set
849 	 * If MSG_WAITALL is set but resid is larger than the receive buffer,
850 	 * we have to do the receive in sections, and thus risk returning
851 	 * a short count if a timeout or signal occurs after we start.
852 	 */
853 	if (m == 0 || (((flags & MSG_DONTWAIT) == 0 &&
854 	    so->so_rcv.sb_cc < uio->uio_resid) &&
855 	    (so->so_rcv.sb_cc < so->so_rcv.sb_lowat ||
856 	    ((flags & MSG_WAITALL) && uio->uio_resid <= so->so_rcv.sb_hiwat)) &&
857 	    m->m_nextpkt == 0 && (pr->pr_flags & PR_ATOMIC) == 0)) {
858 		KASSERT(m != 0 || !so->so_rcv.sb_cc,
859 		    ("receive: m == %p so->so_rcv.sb_cc == %u",
860 		    m, so->so_rcv.sb_cc));
861 		if (so->so_error) {
862 			if (m)
863 				goto dontblock;
864 			error = so->so_error;
865 			if ((flags & MSG_PEEK) == 0)
866 				so->so_error = 0;
867 			goto release;
868 		}
869 		if (so->so_state & SS_CANTRCVMORE) {
870 			if (m)
871 				goto dontblock;
872 			else
873 				goto release;
874 		}
875 		for (; m; m = m->m_next)
876 			if (m->m_type == MT_OOBDATA  || (m->m_flags & M_EOR)) {
877 				m = so->so_rcv.sb_mb;
878 				goto dontblock;
879 			}
880 		if ((so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING)) == 0 &&
881 		    (so->so_proto->pr_flags & PR_CONNREQUIRED)) {
882 			error = ENOTCONN;
883 			goto release;
884 		}
885 		if (uio->uio_resid == 0)
886 			goto release;
887 		if ((so->so_state & SS_NBIO) || (flags & MSG_DONTWAIT)) {
888 			error = EWOULDBLOCK;
889 			goto release;
890 		}
891 		SBLASTRECORDCHK(&so->so_rcv);
892 		SBLASTMBUFCHK(&so->so_rcv);
893 		sbunlock(&so->so_rcv);
894 		error = sbwait(&so->so_rcv);
895 		splx(s);
896 		if (error)
897 			return (error);
898 		goto restart;
899 	}
900 dontblock:
901 	if (uio->uio_td)
902 		uio->uio_td->td_proc->p_stats->p_ru.ru_msgrcv++;
903 	SBLASTRECORDCHK(&so->so_rcv);
904 	SBLASTMBUFCHK(&so->so_rcv);
905 	nextrecord = m->m_nextpkt;
906 	if (pr->pr_flags & PR_ADDR) {
907 		KASSERT(m->m_type == MT_SONAME,
908 		    ("m->m_type == %d", m->m_type));
909 		orig_resid = 0;
910 		if (psa)
911 			*psa = dup_sockaddr(mtod(m, struct sockaddr *),
912 					    mp0 == 0);
913 		if (flags & MSG_PEEK) {
914 			m = m->m_next;
915 		} else {
916 			sbfree(&so->so_rcv, m);
917 			so->so_rcv.sb_mb = m_free(m);
918 			m = so->so_rcv.sb_mb;
919 		}
920 	}
921 	while (m && m->m_type == MT_CONTROL && error == 0) {
922 		if (flags & MSG_PEEK) {
923 			if (controlp)
924 				*controlp = m_copy(m, 0, m->m_len);
925 			m = m->m_next;
926 		} else {
927 			sbfree(&so->so_rcv, m);
928 			so->so_rcv.sb_mb = m->m_next;
929 			m->m_next = NULL;
930 			if (pr->pr_domain->dom_externalize)
931 				error =
932 				(*pr->pr_domain->dom_externalize)(m, controlp);
933 			else if (controlp)
934 				*controlp = m;
935 			else
936 				m_freem(m);
937 			m = so->so_rcv.sb_mb;
938 		}
939 		if (controlp) {
940 			orig_resid = 0;
941 			while (*controlp != NULL)
942 				controlp = &(*controlp)->m_next;
943 		}
944 	}
945 	if (m) {
946 		if ((flags & MSG_PEEK) == 0) {
947 			m->m_nextpkt = nextrecord;
948 			/*
949 			 * If nextrecord == NULL (this is a single chain),
950 			 * then sb_lastrecord may not be valid here if m
951 			 * was changed earlier.
952 			 */
953 			if (nextrecord == NULL) {
954 				KASSERT(so->so_rcv.sb_mb == m,
955 					("receive tailq 1"));
956 				so->so_rcv.sb_lastrecord = m;
957 			}
958 		}
959 		type = m->m_type;
960 		if (type == MT_OOBDATA)
961 			flags |= MSG_OOB;
962 	} else {
963 		if ((flags & MSG_PEEK) == 0) {
964 			KASSERT(so->so_rcv.sb_mb == m,("receive tailq 2"));
965 			so->so_rcv.sb_mb = nextrecord;
966 			SB_EMPTY_FIXUP(&so->so_rcv);
967 		}
968 	}
969 	SBLASTRECORDCHK(&so->so_rcv);
970 	SBLASTMBUFCHK(&so->so_rcv);
971 
972 	moff = 0;
973 	offset = 0;
974 	while (m && uio->uio_resid > 0 && error == 0) {
975 		if (m->m_type == MT_OOBDATA) {
976 			if (type != MT_OOBDATA)
977 				break;
978 		} else if (type == MT_OOBDATA)
979 			break;
980 		else
981 		    KASSERT(m->m_type == MT_DATA || m->m_type == MT_HEADER,
982 			("m->m_type == %d", m->m_type));
983 		so->so_state &= ~SS_RCVATMARK;
984 		len = uio->uio_resid;
985 		if (so->so_oobmark && len > so->so_oobmark - offset)
986 			len = so->so_oobmark - offset;
987 		if (len > m->m_len - moff)
988 			len = m->m_len - moff;
989 		/*
990 		 * If mp is set, just pass back the mbufs.
991 		 * Otherwise copy them out via the uio, then free.
992 		 * Sockbuf must be consistent here (points to current mbuf,
993 		 * it points to next record) when we drop priority;
994 		 * we must note any additions to the sockbuf when we
995 		 * block interrupts again.
996 		 */
997 		if (mp == 0) {
998 			SBLASTRECORDCHK(&so->so_rcv);
999 			SBLASTMBUFCHK(&so->so_rcv);
1000 			splx(s);
1001 #ifdef ZERO_COPY_SOCKETS
1002 			if (so_zero_copy_receive) {
1003 				vm_page_t pg;
1004 				int disposable;
1005 
1006 				if ((m->m_flags & M_EXT)
1007 				 && (m->m_ext.ext_type == EXT_DISPOSABLE))
1008 					disposable = 1;
1009 				else
1010 					disposable = 0;
1011 
1012 				pg = PHYS_TO_VM_PAGE(vtophys(mtod(m, caddr_t) +
1013 					moff));
1014 
1015 				if (uio->uio_offset == -1)
1016 					uio->uio_offset =IDX_TO_OFF(pg->pindex);
1017 
1018 				error = uiomoveco(mtod(m, char *) + moff,
1019 						  (int)len, uio,pg->object,
1020 						  disposable);
1021 			} else
1022 #endif /* ZERO_COPY_SOCKETS */
1023 			error = uiomove(mtod(m, char *) + moff, (int)len, uio);
1024 			s = splnet();
1025 			if (error)
1026 				goto release;
1027 		} else
1028 			uio->uio_resid -= len;
1029 		if (len == m->m_len - moff) {
1030 			if (m->m_flags & M_EOR)
1031 				flags |= MSG_EOR;
1032 			if (flags & MSG_PEEK) {
1033 				m = m->m_next;
1034 				moff = 0;
1035 			} else {
1036 				nextrecord = m->m_nextpkt;
1037 				sbfree(&so->so_rcv, m);
1038 				if (mp) {
1039 					*mp = m;
1040 					mp = &m->m_next;
1041 					so->so_rcv.sb_mb = m = m->m_next;
1042 					*mp = (struct mbuf *)0;
1043 				} else {
1044 					so->so_rcv.sb_mb = m_free(m);
1045 					m = so->so_rcv.sb_mb;
1046 				}
1047 				if (m) {
1048 					m->m_nextpkt = nextrecord;
1049 					if (nextrecord == NULL)
1050 						so->so_rcv.sb_lastrecord = m;
1051 				} else {
1052 					so->so_rcv.sb_mb = nextrecord;
1053 					SB_EMPTY_FIXUP(&so->so_rcv);
1054 				}
1055 				SBLASTRECORDCHK(&so->so_rcv);
1056 				SBLASTMBUFCHK(&so->so_rcv);
1057 			}
1058 		} else {
1059 			if (flags & MSG_PEEK)
1060 				moff += len;
1061 			else {
1062 				if (mp)
1063 					*mp = m_copym(m, 0, len, M_TRYWAIT);
1064 				m->m_data += len;
1065 				m->m_len -= len;
1066 				so->so_rcv.sb_cc -= len;
1067 			}
1068 		}
1069 		if (so->so_oobmark) {
1070 			if ((flags & MSG_PEEK) == 0) {
1071 				so->so_oobmark -= len;
1072 				if (so->so_oobmark == 0) {
1073 					so->so_state |= SS_RCVATMARK;
1074 					break;
1075 				}
1076 			} else {
1077 				offset += len;
1078 				if (offset == so->so_oobmark)
1079 					break;
1080 			}
1081 		}
1082 		if (flags & MSG_EOR)
1083 			break;
1084 		/*
1085 		 * If the MSG_WAITALL flag is set (for non-atomic socket),
1086 		 * we must not quit until "uio->uio_resid == 0" or an error
1087 		 * termination.  If a signal/timeout occurs, return
1088 		 * with a short count but without error.
1089 		 * Keep sockbuf locked against other readers.
1090 		 */
1091 		while (flags & MSG_WAITALL && m == 0 && uio->uio_resid > 0 &&
1092 		    !sosendallatonce(so) && !nextrecord) {
1093 			if (so->so_error || so->so_state & SS_CANTRCVMORE)
1094 				break;
1095 			/*
1096 			 * Notify the protocol that some data has been
1097 			 * drained before blocking.
1098 			 */
1099 			if (pr->pr_flags & PR_WANTRCVD && so->so_pcb)
1100 				(*pr->pr_usrreqs->pru_rcvd)(so, flags);
1101 			SBLASTRECORDCHK(&so->so_rcv);
1102 			SBLASTMBUFCHK(&so->so_rcv);
1103 			error = sbwait(&so->so_rcv);
1104 			if (error) {
1105 				sbunlock(&so->so_rcv);
1106 				splx(s);
1107 				return (0);
1108 			}
1109 			m = so->so_rcv.sb_mb;
1110 			if (m)
1111 				nextrecord = m->m_nextpkt;
1112 		}
1113 	}
1114 
1115 	if (m && pr->pr_flags & PR_ATOMIC) {
1116 		flags |= MSG_TRUNC;
1117 		if ((flags & MSG_PEEK) == 0)
1118 			(void) sbdroprecord(&so->so_rcv);
1119 	}
1120 	if ((flags & MSG_PEEK) == 0) {
1121 		if (m == 0) {
1122 			/*
1123 			 * First part is an inline SB_EMPTY_FIXUP().  Second
1124 			 * part makes sure sb_lastrecord is up-to-date if
1125 			 * there is still data in the socket buffer.
1126 			 */
1127 			so->so_rcv.sb_mb = nextrecord;
1128 			if (so->so_rcv.sb_mb == NULL) {
1129 				so->so_rcv.sb_mbtail = NULL;
1130 				so->so_rcv.sb_lastrecord = NULL;
1131 			} else if (nextrecord->m_nextpkt == NULL)
1132 				so->so_rcv.sb_lastrecord = nextrecord;
1133 		}
1134 		SBLASTRECORDCHK(&so->so_rcv);
1135 		SBLASTMBUFCHK(&so->so_rcv);
1136 		if (pr->pr_flags & PR_WANTRCVD && so->so_pcb)
1137 			(*pr->pr_usrreqs->pru_rcvd)(so, flags);
1138 	}
1139 	if (orig_resid == uio->uio_resid && orig_resid &&
1140 	    (flags & MSG_EOR) == 0 && (so->so_state & SS_CANTRCVMORE) == 0) {
1141 		sbunlock(&so->so_rcv);
1142 		splx(s);
1143 		goto restart;
1144 	}
1145 
1146 	if (flagsp)
1147 		*flagsp |= flags;
1148 release:
1149 	sbunlock(&so->so_rcv);
1150 	splx(s);
1151 	return (error);
1152 }
1153 
1154 int
1155 soshutdown(so, how)
1156 	struct socket *so;
1157 	int how;
1158 {
1159 	struct protosw *pr = so->so_proto;
1160 
1161 	if (!(how == SHUT_RD || how == SHUT_WR || how == SHUT_RDWR))
1162 		return (EINVAL);
1163 
1164 	if (how != SHUT_WR)
1165 		sorflush(so);
1166 	if (how != SHUT_RD)
1167 		return ((*pr->pr_usrreqs->pru_shutdown)(so));
1168 	return (0);
1169 }
1170 
1171 void
1172 sorflush(so)
1173 	struct socket *so;
1174 {
1175 	struct sockbuf *sb = &so->so_rcv;
1176 	struct protosw *pr = so->so_proto;
1177 	int s;
1178 	struct sockbuf asb;
1179 
1180 	sb->sb_flags |= SB_NOINTR;
1181 	(void) sblock(sb, M_WAITOK);
1182 	s = splimp();
1183 	socantrcvmore(so);
1184 	sbunlock(sb);
1185 	asb = *sb;
1186 	/*
1187 	 * Invalidate/clear most of the sockbuf structure, but keep
1188 	 * its selinfo structure valid.
1189 	 */
1190 	bzero(&sb->sb_startzero,
1191 	    sizeof(*sb) - offsetof(struct sockbuf, sb_startzero));
1192 	splx(s);
1193 
1194 	if (pr->pr_flags & PR_RIGHTS && pr->pr_domain->dom_dispose)
1195 		(*pr->pr_domain->dom_dispose)(asb.sb_mb);
1196 	sbrelease(&asb, so);
1197 }
1198 
1199 #ifdef INET
1200 static int
1201 do_setopt_accept_filter(so, sopt)
1202 	struct	socket *so;
1203 	struct	sockopt *sopt;
1204 {
1205 	struct accept_filter_arg	*afap = NULL;
1206 	struct accept_filter	*afp;
1207 	struct so_accf	*af = so->so_accf;
1208 	int	error = 0;
1209 
1210 	/* do not set/remove accept filters on non listen sockets */
1211 	if ((so->so_options & SO_ACCEPTCONN) == 0) {
1212 		error = EINVAL;
1213 		goto out;
1214 	}
1215 
1216 	/* removing the filter */
1217 	if (sopt == NULL) {
1218 		if (af != NULL) {
1219 			if (af->so_accept_filter != NULL &&
1220 				af->so_accept_filter->accf_destroy != NULL) {
1221 				af->so_accept_filter->accf_destroy(so);
1222 			}
1223 			if (af->so_accept_filter_str != NULL) {
1224 				FREE(af->so_accept_filter_str, M_ACCF);
1225 			}
1226 			FREE(af, M_ACCF);
1227 			so->so_accf = NULL;
1228 		}
1229 		so->so_options &= ~SO_ACCEPTFILTER;
1230 		return (0);
1231 	}
1232 	/* adding a filter */
1233 	/* must remove previous filter first */
1234 	if (af != NULL) {
1235 		error = EINVAL;
1236 		goto out;
1237 	}
1238 	/* don't put large objects on the kernel stack */
1239 	MALLOC(afap, struct accept_filter_arg *, sizeof(*afap), M_TEMP, M_WAITOK);
1240 	error = sooptcopyin(sopt, afap, sizeof *afap, sizeof *afap);
1241 	afap->af_name[sizeof(afap->af_name)-1] = '\0';
1242 	afap->af_arg[sizeof(afap->af_arg)-1] = '\0';
1243 	if (error)
1244 		goto out;
1245 	afp = accept_filt_get(afap->af_name);
1246 	if (afp == NULL) {
1247 		error = ENOENT;
1248 		goto out;
1249 	}
1250 	MALLOC(af, struct so_accf *, sizeof(*af), M_ACCF, M_WAITOK | M_ZERO);
1251 	if (afp->accf_create != NULL) {
1252 		if (afap->af_name[0] != '\0') {
1253 			int len = strlen(afap->af_name) + 1;
1254 
1255 			MALLOC(af->so_accept_filter_str, char *, len, M_ACCF, M_WAITOK);
1256 			strcpy(af->so_accept_filter_str, afap->af_name);
1257 		}
1258 		af->so_accept_filter_arg = afp->accf_create(so, afap->af_arg);
1259 		if (af->so_accept_filter_arg == NULL) {
1260 			FREE(af->so_accept_filter_str, M_ACCF);
1261 			FREE(af, M_ACCF);
1262 			so->so_accf = NULL;
1263 			error = EINVAL;
1264 			goto out;
1265 		}
1266 	}
1267 	af->so_accept_filter = afp;
1268 	so->so_accf = af;
1269 	so->so_options |= SO_ACCEPTFILTER;
1270 out:
1271 	if (afap != NULL)
1272 		FREE(afap, M_TEMP);
1273 	return (error);
1274 }
1275 #endif /* INET */
1276 
1277 /*
1278  * Perhaps this routine, and sooptcopyout(), below, ought to come in
1279  * an additional variant to handle the case where the option value needs
1280  * to be some kind of integer, but not a specific size.
1281  * In addition to their use here, these functions are also called by the
1282  * protocol-level pr_ctloutput() routines.
1283  */
1284 int
1285 sooptcopyin(sopt, buf, len, minlen)
1286 	struct	sockopt *sopt;
1287 	void	*buf;
1288 	size_t	len;
1289 	size_t	minlen;
1290 {
1291 	size_t	valsize;
1292 
1293 	/*
1294 	 * If the user gives us more than we wanted, we ignore it,
1295 	 * but if we don't get the minimum length the caller
1296 	 * wants, we return EINVAL.  On success, sopt->sopt_valsize
1297 	 * is set to however much we actually retrieved.
1298 	 */
1299 	if ((valsize = sopt->sopt_valsize) < minlen)
1300 		return EINVAL;
1301 	if (valsize > len)
1302 		sopt->sopt_valsize = valsize = len;
1303 
1304 	if (sopt->sopt_td != 0)
1305 		return (copyin(sopt->sopt_val, buf, valsize));
1306 
1307 	bcopy(sopt->sopt_val, buf, valsize);
1308 	return 0;
1309 }
1310 
1311 int
1312 sosetopt(so, sopt)
1313 	struct socket *so;
1314 	struct sockopt *sopt;
1315 {
1316 	int	error, optval;
1317 	struct	linger l;
1318 	struct	timeval tv;
1319 	u_long  val;
1320 #ifdef MAC
1321 	struct mac extmac;
1322 #endif
1323 
1324 	error = 0;
1325 	if (sopt->sopt_level != SOL_SOCKET) {
1326 		if (so->so_proto && so->so_proto->pr_ctloutput)
1327 			return ((*so->so_proto->pr_ctloutput)
1328 				  (so, sopt));
1329 		error = ENOPROTOOPT;
1330 	} else {
1331 		switch (sopt->sopt_name) {
1332 #ifdef INET
1333 		case SO_ACCEPTFILTER:
1334 			error = do_setopt_accept_filter(so, sopt);
1335 			if (error)
1336 				goto bad;
1337 			break;
1338 #endif
1339 		case SO_LINGER:
1340 			error = sooptcopyin(sopt, &l, sizeof l, sizeof l);
1341 			if (error)
1342 				goto bad;
1343 
1344 			so->so_linger = l.l_linger;
1345 			if (l.l_onoff)
1346 				so->so_options |= SO_LINGER;
1347 			else
1348 				so->so_options &= ~SO_LINGER;
1349 			break;
1350 
1351 		case SO_DEBUG:
1352 		case SO_KEEPALIVE:
1353 		case SO_DONTROUTE:
1354 		case SO_USELOOPBACK:
1355 		case SO_BROADCAST:
1356 		case SO_REUSEADDR:
1357 		case SO_REUSEPORT:
1358 		case SO_OOBINLINE:
1359 		case SO_TIMESTAMP:
1360 		case SO_NOSIGPIPE:
1361 			error = sooptcopyin(sopt, &optval, sizeof optval,
1362 					    sizeof optval);
1363 			if (error)
1364 				goto bad;
1365 			if (optval)
1366 				so->so_options |= sopt->sopt_name;
1367 			else
1368 				so->so_options &= ~sopt->sopt_name;
1369 			break;
1370 
1371 		case SO_SNDBUF:
1372 		case SO_RCVBUF:
1373 		case SO_SNDLOWAT:
1374 		case SO_RCVLOWAT:
1375 			error = sooptcopyin(sopt, &optval, sizeof optval,
1376 					    sizeof optval);
1377 			if (error)
1378 				goto bad;
1379 
1380 			/*
1381 			 * Values < 1 make no sense for any of these
1382 			 * options, so disallow them.
1383 			 */
1384 			if (optval < 1) {
1385 				error = EINVAL;
1386 				goto bad;
1387 			}
1388 
1389 			switch (sopt->sopt_name) {
1390 			case SO_SNDBUF:
1391 			case SO_RCVBUF:
1392 				if (sbreserve(sopt->sopt_name == SO_SNDBUF ?
1393 				    &so->so_snd : &so->so_rcv, (u_long)optval,
1394 				    so, curthread) == 0) {
1395 					error = ENOBUFS;
1396 					goto bad;
1397 				}
1398 				break;
1399 
1400 			/*
1401 			 * Make sure the low-water is never greater than
1402 			 * the high-water.
1403 			 */
1404 			case SO_SNDLOWAT:
1405 				so->so_snd.sb_lowat =
1406 				    (optval > so->so_snd.sb_hiwat) ?
1407 				    so->so_snd.sb_hiwat : optval;
1408 				break;
1409 			case SO_RCVLOWAT:
1410 				so->so_rcv.sb_lowat =
1411 				    (optval > so->so_rcv.sb_hiwat) ?
1412 				    so->so_rcv.sb_hiwat : optval;
1413 				break;
1414 			}
1415 			break;
1416 
1417 		case SO_SNDTIMEO:
1418 		case SO_RCVTIMEO:
1419 			error = sooptcopyin(sopt, &tv, sizeof tv,
1420 					    sizeof tv);
1421 			if (error)
1422 				goto bad;
1423 
1424 			/* assert(hz > 0); */
1425 			if (tv.tv_sec < 0 || tv.tv_sec > SHRT_MAX / hz ||
1426 			    tv.tv_usec < 0 || tv.tv_usec >= 1000000) {
1427 				error = EDOM;
1428 				goto bad;
1429 			}
1430 			/* assert(tick > 0); */
1431 			/* assert(ULONG_MAX - SHRT_MAX >= 1000000); */
1432 			val = (u_long)(tv.tv_sec * hz) + tv.tv_usec / tick;
1433 			if (val > SHRT_MAX) {
1434 				error = EDOM;
1435 				goto bad;
1436 			}
1437 			if (val == 0 && tv.tv_usec != 0)
1438 				val = 1;
1439 
1440 			switch (sopt->sopt_name) {
1441 			case SO_SNDTIMEO:
1442 				so->so_snd.sb_timeo = val;
1443 				break;
1444 			case SO_RCVTIMEO:
1445 				so->so_rcv.sb_timeo = val;
1446 				break;
1447 			}
1448 			break;
1449 		case SO_LABEL:
1450 #ifdef MAC
1451 			error = sooptcopyin(sopt, &extmac, sizeof extmac,
1452 			    sizeof extmac);
1453 			if (error)
1454 				goto bad;
1455 			error = mac_setsockopt_label(sopt->sopt_td->td_ucred,
1456 			    so, &extmac);
1457 #else
1458 			error = EOPNOTSUPP;
1459 #endif
1460 			break;
1461 		default:
1462 			error = ENOPROTOOPT;
1463 			break;
1464 		}
1465 		if (error == 0 && so->so_proto && so->so_proto->pr_ctloutput) {
1466 			(void) ((*so->so_proto->pr_ctloutput)
1467 				  (so, sopt));
1468 		}
1469 	}
1470 bad:
1471 	return (error);
1472 }
1473 
1474 /* Helper routine for getsockopt */
1475 int
1476 sooptcopyout(struct sockopt *sopt, const void *buf, size_t len)
1477 {
1478 	int	error;
1479 	size_t	valsize;
1480 
1481 	error = 0;
1482 
1483 	/*
1484 	 * Documented get behavior is that we always return a value,
1485 	 * possibly truncated to fit in the user's buffer.
1486 	 * Traditional behavior is that we always tell the user
1487 	 * precisely how much we copied, rather than something useful
1488 	 * like the total amount we had available for her.
1489 	 * Note that this interface is not idempotent; the entire answer must
1490 	 * generated ahead of time.
1491 	 */
1492 	valsize = min(len, sopt->sopt_valsize);
1493 	sopt->sopt_valsize = valsize;
1494 	if (sopt->sopt_val != 0) {
1495 		if (sopt->sopt_td != 0)
1496 			error = copyout(buf, sopt->sopt_val, valsize);
1497 		else
1498 			bcopy(buf, sopt->sopt_val, valsize);
1499 	}
1500 	return error;
1501 }
1502 
1503 int
1504 sogetopt(so, sopt)
1505 	struct socket *so;
1506 	struct sockopt *sopt;
1507 {
1508 	int	error, optval;
1509 	struct	linger l;
1510 	struct	timeval tv;
1511 #ifdef INET
1512 	struct accept_filter_arg *afap;
1513 #endif
1514 #ifdef MAC
1515 	struct mac extmac;
1516 #endif
1517 
1518 	error = 0;
1519 	if (sopt->sopt_level != SOL_SOCKET) {
1520 		if (so->so_proto && so->so_proto->pr_ctloutput) {
1521 			return ((*so->so_proto->pr_ctloutput)
1522 				  (so, sopt));
1523 		} else
1524 			return (ENOPROTOOPT);
1525 	} else {
1526 		switch (sopt->sopt_name) {
1527 #ifdef INET
1528 		case SO_ACCEPTFILTER:
1529 			if ((so->so_options & SO_ACCEPTCONN) == 0)
1530 				return (EINVAL);
1531 			MALLOC(afap, struct accept_filter_arg *, sizeof(*afap),
1532 				M_TEMP, M_WAITOK | M_ZERO);
1533 			if ((so->so_options & SO_ACCEPTFILTER) != 0) {
1534 				strcpy(afap->af_name, so->so_accf->so_accept_filter->accf_name);
1535 				if (so->so_accf->so_accept_filter_str != NULL)
1536 					strcpy(afap->af_arg, so->so_accf->so_accept_filter_str);
1537 			}
1538 			error = sooptcopyout(sopt, afap, sizeof(*afap));
1539 			FREE(afap, M_TEMP);
1540 			break;
1541 #endif
1542 
1543 		case SO_LINGER:
1544 			l.l_onoff = so->so_options & SO_LINGER;
1545 			l.l_linger = so->so_linger;
1546 			error = sooptcopyout(sopt, &l, sizeof l);
1547 			break;
1548 
1549 		case SO_USELOOPBACK:
1550 		case SO_DONTROUTE:
1551 		case SO_DEBUG:
1552 		case SO_KEEPALIVE:
1553 		case SO_REUSEADDR:
1554 		case SO_REUSEPORT:
1555 		case SO_BROADCAST:
1556 		case SO_OOBINLINE:
1557 		case SO_TIMESTAMP:
1558 		case SO_NOSIGPIPE:
1559 			optval = so->so_options & sopt->sopt_name;
1560 integer:
1561 			error = sooptcopyout(sopt, &optval, sizeof optval);
1562 			break;
1563 
1564 		case SO_TYPE:
1565 			optval = so->so_type;
1566 			goto integer;
1567 
1568 		case SO_ERROR:
1569 			optval = so->so_error;
1570 			so->so_error = 0;
1571 			goto integer;
1572 
1573 		case SO_SNDBUF:
1574 			optval = so->so_snd.sb_hiwat;
1575 			goto integer;
1576 
1577 		case SO_RCVBUF:
1578 			optval = so->so_rcv.sb_hiwat;
1579 			goto integer;
1580 
1581 		case SO_SNDLOWAT:
1582 			optval = so->so_snd.sb_lowat;
1583 			goto integer;
1584 
1585 		case SO_RCVLOWAT:
1586 			optval = so->so_rcv.sb_lowat;
1587 			goto integer;
1588 
1589 		case SO_SNDTIMEO:
1590 		case SO_RCVTIMEO:
1591 			optval = (sopt->sopt_name == SO_SNDTIMEO ?
1592 				  so->so_snd.sb_timeo : so->so_rcv.sb_timeo);
1593 
1594 			tv.tv_sec = optval / hz;
1595 			tv.tv_usec = (optval % hz) * tick;
1596 			error = sooptcopyout(sopt, &tv, sizeof tv);
1597 			break;
1598 		case SO_LABEL:
1599 #ifdef MAC
1600 			error = sooptcopyin(sopt, &extmac, sizeof(extmac),
1601 			    sizeof(extmac));
1602 			if (error)
1603 				return (error);
1604 			error = mac_getsockopt_label(sopt->sopt_td->td_ucred,
1605 			    so, &extmac);
1606 			if (error)
1607 				return (error);
1608 			error = sooptcopyout(sopt, &extmac, sizeof extmac);
1609 #else
1610 			error = EOPNOTSUPP;
1611 #endif
1612 			break;
1613 		case SO_PEERLABEL:
1614 #ifdef MAC
1615 			error = sooptcopyin(sopt, &extmac, sizeof(extmac),
1616 			    sizeof(extmac));
1617 			if (error)
1618 				return (error);
1619 			error = mac_getsockopt_peerlabel(
1620 			    sopt->sopt_td->td_ucred, so, &extmac);
1621 			if (error)
1622 				return (error);
1623 			error = sooptcopyout(sopt, &extmac, sizeof extmac);
1624 #else
1625 			error = EOPNOTSUPP;
1626 #endif
1627 			break;
1628 		default:
1629 			error = ENOPROTOOPT;
1630 			break;
1631 		}
1632 		return (error);
1633 	}
1634 }
1635 
1636 /* XXX; prepare mbuf for (__FreeBSD__ < 3) routines. */
1637 int
1638 soopt_getm(struct sockopt *sopt, struct mbuf **mp)
1639 {
1640 	struct mbuf *m, *m_prev;
1641 	int sopt_size = sopt->sopt_valsize;
1642 
1643 	MGET(m, sopt->sopt_td ? M_TRYWAIT : M_DONTWAIT, MT_DATA);
1644 	if (m == 0)
1645 		return ENOBUFS;
1646 	if (sopt_size > MLEN) {
1647 		MCLGET(m, sopt->sopt_td ? M_TRYWAIT : M_DONTWAIT);
1648 		if ((m->m_flags & M_EXT) == 0) {
1649 			m_free(m);
1650 			return ENOBUFS;
1651 		}
1652 		m->m_len = min(MCLBYTES, sopt_size);
1653 	} else {
1654 		m->m_len = min(MLEN, sopt_size);
1655 	}
1656 	sopt_size -= m->m_len;
1657 	*mp = m;
1658 	m_prev = m;
1659 
1660 	while (sopt_size) {
1661 		MGET(m, sopt->sopt_td ? M_TRYWAIT : M_DONTWAIT, MT_DATA);
1662 		if (m == 0) {
1663 			m_freem(*mp);
1664 			return ENOBUFS;
1665 		}
1666 		if (sopt_size > MLEN) {
1667 			MCLGET(m, sopt->sopt_td ? M_TRYWAIT : M_DONTWAIT);
1668 			if ((m->m_flags & M_EXT) == 0) {
1669 				m_freem(m);
1670 				m_freem(*mp);
1671 				return ENOBUFS;
1672 			}
1673 			m->m_len = min(MCLBYTES, sopt_size);
1674 		} else {
1675 			m->m_len = min(MLEN, sopt_size);
1676 		}
1677 		sopt_size -= m->m_len;
1678 		m_prev->m_next = m;
1679 		m_prev = m;
1680 	}
1681 	return 0;
1682 }
1683 
1684 /* XXX; copyin sopt data into mbuf chain for (__FreeBSD__ < 3) routines. */
1685 int
1686 soopt_mcopyin(struct sockopt *sopt, struct mbuf *m)
1687 {
1688 	struct mbuf *m0 = m;
1689 
1690 	if (sopt->sopt_val == NULL)
1691 		return 0;
1692 	while (m != NULL && sopt->sopt_valsize >= m->m_len) {
1693 		if (sopt->sopt_td != NULL) {
1694 			int error;
1695 
1696 			error = copyin(sopt->sopt_val, mtod(m, char *),
1697 				       m->m_len);
1698 			if (error != 0) {
1699 				m_freem(m0);
1700 				return(error);
1701 			}
1702 		} else
1703 			bcopy(sopt->sopt_val, mtod(m, char *), m->m_len);
1704 		sopt->sopt_valsize -= m->m_len;
1705 		(caddr_t)sopt->sopt_val += m->m_len;
1706 		m = m->m_next;
1707 	}
1708 	if (m != NULL) /* should be allocated enoughly at ip6_sooptmcopyin() */
1709 		panic("ip6_sooptmcopyin");
1710 	return 0;
1711 }
1712 
1713 /* XXX; copyout mbuf chain data into soopt for (__FreeBSD__ < 3) routines. */
1714 int
1715 soopt_mcopyout(struct sockopt *sopt, struct mbuf *m)
1716 {
1717 	struct mbuf *m0 = m;
1718 	size_t valsize = 0;
1719 
1720 	if (sopt->sopt_val == NULL)
1721 		return 0;
1722 	while (m != NULL && sopt->sopt_valsize >= m->m_len) {
1723 		if (sopt->sopt_td != NULL) {
1724 			int error;
1725 
1726 			error = copyout(mtod(m, char *), sopt->sopt_val,
1727 				       m->m_len);
1728 			if (error != 0) {
1729 				m_freem(m0);
1730 				return(error);
1731 			}
1732 		} else
1733 			bcopy(mtod(m, char *), sopt->sopt_val, m->m_len);
1734 	       sopt->sopt_valsize -= m->m_len;
1735 	       (caddr_t)sopt->sopt_val += m->m_len;
1736 	       valsize += m->m_len;
1737 	       m = m->m_next;
1738 	}
1739 	if (m != NULL) {
1740 		/* enough soopt buffer should be given from user-land */
1741 		m_freem(m0);
1742 		return(EINVAL);
1743 	}
1744 	sopt->sopt_valsize = valsize;
1745 	return 0;
1746 }
1747 
1748 void
1749 sohasoutofband(so)
1750 	struct socket *so;
1751 {
1752 	if (so->so_sigio != NULL)
1753 		pgsigio(&so->so_sigio, SIGURG, 0);
1754 	selwakeuppri(&so->so_rcv.sb_sel, PSOCK);
1755 }
1756 
1757 int
1758 sopoll(struct socket *so, int events, struct ucred *active_cred,
1759     struct thread *td)
1760 {
1761 	int revents = 0;
1762 	int s = splnet();
1763 
1764 	if (events & (POLLIN | POLLRDNORM))
1765 		if (soreadable(so))
1766 			revents |= events & (POLLIN | POLLRDNORM);
1767 
1768 	if (events & POLLINIGNEOF)
1769 		if (so->so_rcv.sb_cc >= so->so_rcv.sb_lowat ||
1770 		    !TAILQ_EMPTY(&so->so_comp) || so->so_error)
1771 			revents |= POLLINIGNEOF;
1772 
1773 	if (events & (POLLOUT | POLLWRNORM))
1774 		if (sowriteable(so))
1775 			revents |= events & (POLLOUT | POLLWRNORM);
1776 
1777 	if (events & (POLLPRI | POLLRDBAND))
1778 		if (so->so_oobmark || (so->so_state & SS_RCVATMARK))
1779 			revents |= events & (POLLPRI | POLLRDBAND);
1780 
1781 	if (revents == 0) {
1782 		if (events &
1783 		    (POLLIN | POLLINIGNEOF | POLLPRI | POLLRDNORM |
1784 		     POLLRDBAND)) {
1785 			selrecord(td, &so->so_rcv.sb_sel);
1786 			so->so_rcv.sb_flags |= SB_SEL;
1787 		}
1788 
1789 		if (events & (POLLOUT | POLLWRNORM)) {
1790 			selrecord(td, &so->so_snd.sb_sel);
1791 			so->so_snd.sb_flags |= SB_SEL;
1792 		}
1793 	}
1794 
1795 	splx(s);
1796 	return (revents);
1797 }
1798 
1799 int
1800 soo_kqfilter(struct file *fp, struct knote *kn)
1801 {
1802 	struct socket *so = kn->kn_fp->f_data;
1803 	struct sockbuf *sb;
1804 	int s;
1805 
1806 	switch (kn->kn_filter) {
1807 	case EVFILT_READ:
1808 		if (so->so_options & SO_ACCEPTCONN)
1809 			kn->kn_fop = &solisten_filtops;
1810 		else
1811 			kn->kn_fop = &soread_filtops;
1812 		sb = &so->so_rcv;
1813 		break;
1814 	case EVFILT_WRITE:
1815 		kn->kn_fop = &sowrite_filtops;
1816 		sb = &so->so_snd;
1817 		break;
1818 	default:
1819 		return (1);
1820 	}
1821 
1822 	s = splnet();
1823 	SLIST_INSERT_HEAD(&sb->sb_sel.si_note, kn, kn_selnext);
1824 	sb->sb_flags |= SB_KNOTE;
1825 	splx(s);
1826 	return (0);
1827 }
1828 
1829 static void
1830 filt_sordetach(struct knote *kn)
1831 {
1832 	struct socket *so = kn->kn_fp->f_data;
1833 	int s = splnet();
1834 
1835 	SLIST_REMOVE(&so->so_rcv.sb_sel.si_note, kn, knote, kn_selnext);
1836 	if (SLIST_EMPTY(&so->so_rcv.sb_sel.si_note))
1837 		so->so_rcv.sb_flags &= ~SB_KNOTE;
1838 	splx(s);
1839 }
1840 
1841 /*ARGSUSED*/
1842 static int
1843 filt_soread(struct knote *kn, long hint)
1844 {
1845 	struct socket *so = kn->kn_fp->f_data;
1846 
1847 	kn->kn_data = so->so_rcv.sb_cc - so->so_rcv.sb_ctl;
1848 	if (so->so_state & SS_CANTRCVMORE) {
1849 		kn->kn_flags |= EV_EOF;
1850 		kn->kn_fflags = so->so_error;
1851 		return (1);
1852 	}
1853 	if (so->so_error)	/* temporary udp error */
1854 		return (1);
1855 	if (kn->kn_sfflags & NOTE_LOWAT)
1856 		return (kn->kn_data >= kn->kn_sdata);
1857 	return (so->so_rcv.sb_cc >= so->so_rcv.sb_lowat);
1858 }
1859 
1860 static void
1861 filt_sowdetach(struct knote *kn)
1862 {
1863 	struct socket *so = kn->kn_fp->f_data;
1864 	int s = splnet();
1865 
1866 	SLIST_REMOVE(&so->so_snd.sb_sel.si_note, kn, knote, kn_selnext);
1867 	if (SLIST_EMPTY(&so->so_snd.sb_sel.si_note))
1868 		so->so_snd.sb_flags &= ~SB_KNOTE;
1869 	splx(s);
1870 }
1871 
1872 /*ARGSUSED*/
1873 static int
1874 filt_sowrite(struct knote *kn, long hint)
1875 {
1876 	struct socket *so = kn->kn_fp->f_data;
1877 
1878 	kn->kn_data = sbspace(&so->so_snd);
1879 	if (so->so_state & SS_CANTSENDMORE) {
1880 		kn->kn_flags |= EV_EOF;
1881 		kn->kn_fflags = so->so_error;
1882 		return (1);
1883 	}
1884 	if (so->so_error)	/* temporary udp error */
1885 		return (1);
1886 	if (((so->so_state & SS_ISCONNECTED) == 0) &&
1887 	    (so->so_proto->pr_flags & PR_CONNREQUIRED))
1888 		return (0);
1889 	if (kn->kn_sfflags & NOTE_LOWAT)
1890 		return (kn->kn_data >= kn->kn_sdata);
1891 	return (kn->kn_data >= so->so_snd.sb_lowat);
1892 }
1893 
1894 /*ARGSUSED*/
1895 static int
1896 filt_solisten(struct knote *kn, long hint)
1897 {
1898 	struct socket *so = kn->kn_fp->f_data;
1899 
1900 	kn->kn_data = so->so_qlen;
1901 	return (! TAILQ_EMPTY(&so->so_comp));
1902 }
1903 
1904 int
1905 socheckuid(struct socket *so, uid_t uid)
1906 {
1907 
1908 	if (so == NULL)
1909 		return (EPERM);
1910 	if (so->so_cred->cr_uid == uid)
1911 		return (0);
1912 	return (EPERM);
1913 }
1914