xref: /freebsd/sys/kern/uipc_syscalls.c (revision 5c8e8e82aeaf3aa788acdd6cfca30ef09094230d)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1982, 1986, 1989, 1990, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  *	@(#)uipc_syscalls.c	8.4 (Berkeley) 2/21/94
32  */
33 
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD$");
36 
37 #include "opt_capsicum.h"
38 #include "opt_inet.h"
39 #include "opt_inet6.h"
40 #include "opt_ktrace.h"
41 
42 #include <sys/param.h>
43 #include <sys/systm.h>
44 #include <sys/capsicum.h>
45 #include <sys/kernel.h>
46 #include <sys/lock.h>
47 #include <sys/mutex.h>
48 #include <sys/sysproto.h>
49 #include <sys/malloc.h>
50 #include <sys/filedesc.h>
51 #include <sys/proc.h>
52 #include <sys/filio.h>
53 #include <sys/jail.h>
54 #include <sys/mbuf.h>
55 #include <sys/protosw.h>
56 #include <sys/rwlock.h>
57 #include <sys/socket.h>
58 #include <sys/socketvar.h>
59 #include <sys/syscallsubr.h>
60 #include <sys/sysent.h>
61 #include <sys/uio.h>
62 #include <sys/un.h>
63 #include <sys/unpcb.h>
64 #ifdef KTRACE
65 #include <sys/ktrace.h>
66 #endif
67 #ifdef COMPAT_FREEBSD32
68 #include <compat/freebsd32/freebsd32_util.h>
69 #endif
70 
71 #include <net/vnet.h>
72 
73 #include <security/audit/audit.h>
74 #include <security/mac/mac_framework.h>
75 
76 static int sendit(struct thread *td, int s, struct msghdr *mp, int flags);
77 static int recvit(struct thread *td, int s, struct msghdr *mp, void *namelenp);
78 
79 static int accept1(struct thread *td, int s, struct sockaddr *uname,
80 		   socklen_t *anamelen, int flags);
81 static int getsockname1(struct thread *td, struct getsockname_args *uap,
82 			int compat);
83 static int getpeername1(struct thread *td, struct getpeername_args *uap,
84 			int compat);
85 static int sockargs(struct mbuf **, char *, socklen_t, int);
86 
87 /*
88  * Convert a user file descriptor to a kernel file entry and check if required
89  * capability rights are present.
90  * If required copy of current set of capability rights is returned.
91  * A reference on the file entry is held upon returning.
92  */
93 int
94 getsock_cap(struct thread *td, int fd, cap_rights_t *rightsp,
95     struct file **fpp, u_int *fflagp, struct filecaps *havecapsp)
96 {
97 	struct file *fp;
98 	int error;
99 
100 	error = fget_cap(td, fd, rightsp, &fp, havecapsp);
101 	if (error != 0)
102 		return (error);
103 	if (fp->f_type != DTYPE_SOCKET) {
104 		fdrop(fp, td);
105 		if (havecapsp != NULL)
106 			filecaps_free(havecapsp);
107 		return (ENOTSOCK);
108 	}
109 	if (fflagp != NULL)
110 		*fflagp = fp->f_flag;
111 	*fpp = fp;
112 	return (0);
113 }
114 
115 /*
116  * System call interface to the socket abstraction.
117  */
118 #if defined(COMPAT_43)
119 #define COMPAT_OLDSOCK
120 #endif
121 
122 int
123 sys_socket(struct thread *td, struct socket_args *uap)
124 {
125 
126 	return (kern_socket(td, uap->domain, uap->type, uap->protocol));
127 }
128 
129 int
130 kern_socket(struct thread *td, int domain, int type, int protocol)
131 {
132 	struct socket *so;
133 	struct file *fp;
134 	int fd, error, oflag, fflag;
135 
136 	AUDIT_ARG_SOCKET(domain, type, protocol);
137 
138 	oflag = 0;
139 	fflag = 0;
140 	if ((type & SOCK_CLOEXEC) != 0) {
141 		type &= ~SOCK_CLOEXEC;
142 		oflag |= O_CLOEXEC;
143 	}
144 	if ((type & SOCK_NONBLOCK) != 0) {
145 		type &= ~SOCK_NONBLOCK;
146 		fflag |= FNONBLOCK;
147 	}
148 
149 #ifdef MAC
150 	error = mac_socket_check_create(td->td_ucred, domain, type, protocol);
151 	if (error != 0)
152 		return (error);
153 #endif
154 	error = falloc(td, &fp, &fd, oflag);
155 	if (error != 0)
156 		return (error);
157 	/* An extra reference on `fp' has been held for us by falloc(). */
158 	error = socreate(domain, &so, type, protocol, td->td_ucred, td);
159 	if (error != 0) {
160 		fdclose(td, fp, fd);
161 	} else {
162 		finit(fp, FREAD | FWRITE | fflag, DTYPE_SOCKET, so, &socketops);
163 		if ((fflag & FNONBLOCK) != 0)
164 			(void) fo_ioctl(fp, FIONBIO, &fflag, td->td_ucred, td);
165 		td->td_retval[0] = fd;
166 	}
167 	fdrop(fp, td);
168 	return (error);
169 }
170 
171 int
172 sys_bind(struct thread *td, struct bind_args *uap)
173 {
174 	struct sockaddr *sa;
175 	int error;
176 
177 	error = getsockaddr(&sa, uap->name, uap->namelen);
178 	if (error == 0) {
179 		error = kern_bindat(td, AT_FDCWD, uap->s, sa);
180 		free(sa, M_SONAME);
181 	}
182 	return (error);
183 }
184 
185 int
186 kern_bindat(struct thread *td, int dirfd, int fd, struct sockaddr *sa)
187 {
188 	struct socket *so;
189 	struct file *fp;
190 	int error;
191 
192 #ifdef CAPABILITY_MODE
193 	if (IN_CAPABILITY_MODE(td) && (dirfd == AT_FDCWD))
194 		return (ECAPMODE);
195 #endif
196 
197 	AUDIT_ARG_FD(fd);
198 	AUDIT_ARG_SOCKADDR(td, dirfd, sa);
199 	error = getsock_cap(td, fd, &cap_bind_rights,
200 	    &fp, NULL, NULL);
201 	if (error != 0)
202 		return (error);
203 	so = fp->f_data;
204 #ifdef KTRACE
205 	if (KTRPOINT(td, KTR_STRUCT))
206 		ktrsockaddr(sa);
207 #endif
208 #ifdef MAC
209 	error = mac_socket_check_bind(td->td_ucred, so, sa);
210 	if (error == 0) {
211 #endif
212 		if (dirfd == AT_FDCWD)
213 			error = sobind(so, sa, td);
214 		else
215 			error = sobindat(dirfd, so, sa, td);
216 #ifdef MAC
217 	}
218 #endif
219 	fdrop(fp, td);
220 	return (error);
221 }
222 
223 int
224 sys_bindat(struct thread *td, struct bindat_args *uap)
225 {
226 	struct sockaddr *sa;
227 	int error;
228 
229 	error = getsockaddr(&sa, uap->name, uap->namelen);
230 	if (error == 0) {
231 		error = kern_bindat(td, uap->fd, uap->s, sa);
232 		free(sa, M_SONAME);
233 	}
234 	return (error);
235 }
236 
237 int
238 sys_listen(struct thread *td, struct listen_args *uap)
239 {
240 
241 	return (kern_listen(td, uap->s, uap->backlog));
242 }
243 
244 int
245 kern_listen(struct thread *td, int s, int backlog)
246 {
247 	struct socket *so;
248 	struct file *fp;
249 	int error;
250 
251 	AUDIT_ARG_FD(s);
252 	error = getsock_cap(td, s, &cap_listen_rights,
253 	    &fp, NULL, NULL);
254 	if (error == 0) {
255 		so = fp->f_data;
256 #ifdef MAC
257 		error = mac_socket_check_listen(td->td_ucred, so);
258 		if (error == 0)
259 #endif
260 			error = solisten(so, backlog, td);
261 		fdrop(fp, td);
262 	}
263 	return (error);
264 }
265 
266 /*
267  * accept1()
268  */
269 static int
270 accept1(td, s, uname, anamelen, flags)
271 	struct thread *td;
272 	int s;
273 	struct sockaddr *uname;
274 	socklen_t *anamelen;
275 	int flags;
276 {
277 	struct sockaddr *name;
278 	socklen_t namelen;
279 	struct file *fp;
280 	int error;
281 
282 	if (uname == NULL)
283 		return (kern_accept4(td, s, NULL, NULL, flags, NULL));
284 
285 	error = copyin(anamelen, &namelen, sizeof (namelen));
286 	if (error != 0)
287 		return (error);
288 
289 	error = kern_accept4(td, s, &name, &namelen, flags, &fp);
290 
291 	if (error != 0)
292 		return (error);
293 
294 	if (error == 0 && uname != NULL) {
295 #ifdef COMPAT_OLDSOCK
296 		if (SV_PROC_FLAG(td->td_proc, SV_AOUT) &&
297 		    (flags & ACCEPT4_COMPAT) != 0)
298 			((struct osockaddr *)name)->sa_family =
299 			    name->sa_family;
300 #endif
301 		error = copyout(name, uname, namelen);
302 	}
303 	if (error == 0)
304 		error = copyout(&namelen, anamelen,
305 		    sizeof(namelen));
306 	if (error != 0)
307 		fdclose(td, fp, td->td_retval[0]);
308 	fdrop(fp, td);
309 	free(name, M_SONAME);
310 	return (error);
311 }
312 
313 int
314 kern_accept(struct thread *td, int s, struct sockaddr **name,
315     socklen_t *namelen, struct file **fp)
316 {
317 	return (kern_accept4(td, s, name, namelen, ACCEPT4_INHERIT, fp));
318 }
319 
320 int
321 kern_accept4(struct thread *td, int s, struct sockaddr **name,
322     socklen_t *namelen, int flags, struct file **fp)
323 {
324 	struct file *headfp, *nfp = NULL;
325 	struct sockaddr *sa = NULL;
326 	struct socket *head, *so;
327 	struct filecaps fcaps;
328 	u_int fflag;
329 	pid_t pgid;
330 	int error, fd, tmp;
331 
332 	if (name != NULL)
333 		*name = NULL;
334 
335 	AUDIT_ARG_FD(s);
336 	error = getsock_cap(td, s, &cap_accept_rights,
337 	    &headfp, &fflag, &fcaps);
338 	if (error != 0)
339 		return (error);
340 	head = headfp->f_data;
341 	if (!SOLISTENING(head)) {
342 		error = EINVAL;
343 		goto done;
344 	}
345 #ifdef MAC
346 	error = mac_socket_check_accept(td->td_ucred, head);
347 	if (error != 0)
348 		goto done;
349 #endif
350 	error = falloc_caps(td, &nfp, &fd,
351 	    (flags & SOCK_CLOEXEC) ? O_CLOEXEC : 0, &fcaps);
352 	if (error != 0)
353 		goto done;
354 	SOCK_LOCK(head);
355 	if (!SOLISTENING(head)) {
356 		SOCK_UNLOCK(head);
357 		error = EINVAL;
358 		goto noconnection;
359 	}
360 
361 	error = solisten_dequeue(head, &so, flags);
362 	if (error != 0)
363 		goto noconnection;
364 
365 	/* An extra reference on `nfp' has been held for us by falloc(). */
366 	td->td_retval[0] = fd;
367 
368 	/* Connection has been removed from the listen queue. */
369 	KNOTE_UNLOCKED(&head->so_rdsel.si_note, 0);
370 
371 	if (flags & ACCEPT4_INHERIT) {
372 		pgid = fgetown(&head->so_sigio);
373 		if (pgid != 0)
374 			fsetown(pgid, &so->so_sigio);
375 	} else {
376 		fflag &= ~(FNONBLOCK | FASYNC);
377 		if (flags & SOCK_NONBLOCK)
378 			fflag |= FNONBLOCK;
379 	}
380 
381 	finit(nfp, fflag, DTYPE_SOCKET, so, &socketops);
382 	/* Sync socket nonblocking/async state with file flags */
383 	tmp = fflag & FNONBLOCK;
384 	(void) fo_ioctl(nfp, FIONBIO, &tmp, td->td_ucred, td);
385 	tmp = fflag & FASYNC;
386 	(void) fo_ioctl(nfp, FIOASYNC, &tmp, td->td_ucred, td);
387 	error = soaccept(so, &sa);
388 	if (error != 0)
389 		goto noconnection;
390 	if (sa == NULL) {
391 		if (name)
392 			*namelen = 0;
393 		goto done;
394 	}
395 	AUDIT_ARG_SOCKADDR(td, AT_FDCWD, sa);
396 	if (name) {
397 		/* check sa_len before it is destroyed */
398 		if (*namelen > sa->sa_len)
399 			*namelen = sa->sa_len;
400 #ifdef KTRACE
401 		if (KTRPOINT(td, KTR_STRUCT))
402 			ktrsockaddr(sa);
403 #endif
404 		*name = sa;
405 		sa = NULL;
406 	}
407 noconnection:
408 	free(sa, M_SONAME);
409 
410 	/*
411 	 * close the new descriptor, assuming someone hasn't ripped it
412 	 * out from under us.
413 	 */
414 	if (error != 0)
415 		fdclose(td, nfp, fd);
416 
417 	/*
418 	 * Release explicitly held references before returning.  We return
419 	 * a reference on nfp to the caller on success if they request it.
420 	 */
421 done:
422 	if (nfp == NULL)
423 		filecaps_free(&fcaps);
424 	if (fp != NULL) {
425 		if (error == 0) {
426 			*fp = nfp;
427 			nfp = NULL;
428 		} else
429 			*fp = NULL;
430 	}
431 	if (nfp != NULL)
432 		fdrop(nfp, td);
433 	fdrop(headfp, td);
434 	return (error);
435 }
436 
437 int
438 sys_accept(td, uap)
439 	struct thread *td;
440 	struct accept_args *uap;
441 {
442 
443 	return (accept1(td, uap->s, uap->name, uap->anamelen, ACCEPT4_INHERIT));
444 }
445 
446 int
447 sys_accept4(td, uap)
448 	struct thread *td;
449 	struct accept4_args *uap;
450 {
451 
452 	if (uap->flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
453 		return (EINVAL);
454 
455 	return (accept1(td, uap->s, uap->name, uap->anamelen, uap->flags));
456 }
457 
458 #ifdef COMPAT_OLDSOCK
459 int
460 oaccept(struct thread *td, struct oaccept_args *uap)
461 {
462 
463 	return (accept1(td, uap->s, uap->name, uap->anamelen,
464 	    ACCEPT4_INHERIT | ACCEPT4_COMPAT));
465 }
466 #endif /* COMPAT_OLDSOCK */
467 
468 int
469 sys_connect(struct thread *td, struct connect_args *uap)
470 {
471 	struct sockaddr *sa;
472 	int error;
473 
474 	error = getsockaddr(&sa, uap->name, uap->namelen);
475 	if (error == 0) {
476 		error = kern_connectat(td, AT_FDCWD, uap->s, sa);
477 		free(sa, M_SONAME);
478 	}
479 	return (error);
480 }
481 
482 int
483 kern_connectat(struct thread *td, int dirfd, int fd, struct sockaddr *sa)
484 {
485 	struct socket *so;
486 	struct file *fp;
487 	int error, interrupted = 0;
488 
489 #ifdef CAPABILITY_MODE
490 	if (IN_CAPABILITY_MODE(td) && (dirfd == AT_FDCWD))
491 		return (ECAPMODE);
492 #endif
493 
494 	AUDIT_ARG_FD(fd);
495 	AUDIT_ARG_SOCKADDR(td, dirfd, sa);
496 	error = getsock_cap(td, fd, &cap_connect_rights,
497 	    &fp, NULL, NULL);
498 	if (error != 0)
499 		return (error);
500 	so = fp->f_data;
501 	if (so->so_state & SS_ISCONNECTING) {
502 		error = EALREADY;
503 		goto done1;
504 	}
505 #ifdef KTRACE
506 	if (KTRPOINT(td, KTR_STRUCT))
507 		ktrsockaddr(sa);
508 #endif
509 #ifdef MAC
510 	error = mac_socket_check_connect(td->td_ucred, so, sa);
511 	if (error != 0)
512 		goto bad;
513 #endif
514 	error = soconnectat(dirfd, so, sa, td);
515 	if (error != 0)
516 		goto bad;
517 	if ((so->so_state & SS_NBIO) && (so->so_state & SS_ISCONNECTING)) {
518 		error = EINPROGRESS;
519 		goto done1;
520 	}
521 	SOCK_LOCK(so);
522 	while ((so->so_state & SS_ISCONNECTING) && so->so_error == 0) {
523 		error = msleep(&so->so_timeo, &so->so_lock, PSOCK | PCATCH,
524 		    "connec", 0);
525 		if (error != 0) {
526 			if (error == EINTR || error == ERESTART)
527 				interrupted = 1;
528 			break;
529 		}
530 	}
531 	if (error == 0) {
532 		error = so->so_error;
533 		so->so_error = 0;
534 	}
535 	SOCK_UNLOCK(so);
536 bad:
537 	if (!interrupted)
538 		so->so_state &= ~SS_ISCONNECTING;
539 	if (error == ERESTART)
540 		error = EINTR;
541 done1:
542 	fdrop(fp, td);
543 	return (error);
544 }
545 
546 int
547 sys_connectat(struct thread *td, struct connectat_args *uap)
548 {
549 	struct sockaddr *sa;
550 	int error;
551 
552 	error = getsockaddr(&sa, uap->name, uap->namelen);
553 	if (error == 0) {
554 		error = kern_connectat(td, uap->fd, uap->s, sa);
555 		free(sa, M_SONAME);
556 	}
557 	return (error);
558 }
559 
560 int
561 kern_socketpair(struct thread *td, int domain, int type, int protocol,
562     int *rsv)
563 {
564 	struct file *fp1, *fp2;
565 	struct socket *so1, *so2;
566 	int fd, error, oflag, fflag;
567 
568 	AUDIT_ARG_SOCKET(domain, type, protocol);
569 
570 	oflag = 0;
571 	fflag = 0;
572 	if ((type & SOCK_CLOEXEC) != 0) {
573 		type &= ~SOCK_CLOEXEC;
574 		oflag |= O_CLOEXEC;
575 	}
576 	if ((type & SOCK_NONBLOCK) != 0) {
577 		type &= ~SOCK_NONBLOCK;
578 		fflag |= FNONBLOCK;
579 	}
580 #ifdef MAC
581 	/* We might want to have a separate check for socket pairs. */
582 	error = mac_socket_check_create(td->td_ucred, domain, type,
583 	    protocol);
584 	if (error != 0)
585 		return (error);
586 #endif
587 	error = socreate(domain, &so1, type, protocol, td->td_ucred, td);
588 	if (error != 0)
589 		return (error);
590 	error = socreate(domain, &so2, type, protocol, td->td_ucred, td);
591 	if (error != 0)
592 		goto free1;
593 	/* On success extra reference to `fp1' and 'fp2' is set by falloc. */
594 	error = falloc(td, &fp1, &fd, oflag);
595 	if (error != 0)
596 		goto free2;
597 	rsv[0] = fd;
598 	fp1->f_data = so1;	/* so1 already has ref count */
599 	error = falloc(td, &fp2, &fd, oflag);
600 	if (error != 0)
601 		goto free3;
602 	fp2->f_data = so2;	/* so2 already has ref count */
603 	rsv[1] = fd;
604 	error = soconnect2(so1, so2);
605 	if (error != 0)
606 		goto free4;
607 	if (type == SOCK_DGRAM) {
608 		/*
609 		 * Datagram socket connection is asymmetric.
610 		 */
611 		 error = soconnect2(so2, so1);
612 		 if (error != 0)
613 			goto free4;
614 	} else if (so1->so_proto->pr_flags & PR_CONNREQUIRED) {
615 		struct unpcb *unp, *unp2;
616 		unp = sotounpcb(so1);
617 		unp2 = sotounpcb(so2);
618 		/*
619 		 * No need to lock the unps, because the sockets are brand-new.
620 		 * No other threads can be using them yet
621 		 */
622 		unp_copy_peercred(td, unp, unp2, unp);
623 	}
624 	finit(fp1, FREAD | FWRITE | fflag, DTYPE_SOCKET, fp1->f_data,
625 	    &socketops);
626 	finit(fp2, FREAD | FWRITE | fflag, DTYPE_SOCKET, fp2->f_data,
627 	    &socketops);
628 	if ((fflag & FNONBLOCK) != 0) {
629 		(void) fo_ioctl(fp1, FIONBIO, &fflag, td->td_ucred, td);
630 		(void) fo_ioctl(fp2, FIONBIO, &fflag, td->td_ucred, td);
631 	}
632 	fdrop(fp1, td);
633 	fdrop(fp2, td);
634 	return (0);
635 free4:
636 	fdclose(td, fp2, rsv[1]);
637 	fdrop(fp2, td);
638 free3:
639 	fdclose(td, fp1, rsv[0]);
640 	fdrop(fp1, td);
641 free2:
642 	if (so2 != NULL)
643 		(void)soclose(so2);
644 free1:
645 	if (so1 != NULL)
646 		(void)soclose(so1);
647 	return (error);
648 }
649 
650 int
651 sys_socketpair(struct thread *td, struct socketpair_args *uap)
652 {
653 	int error, sv[2];
654 
655 	error = kern_socketpair(td, uap->domain, uap->type,
656 	    uap->protocol, sv);
657 	if (error != 0)
658 		return (error);
659 	error = copyout(sv, uap->rsv, 2 * sizeof(int));
660 	if (error != 0) {
661 		(void)kern_close(td, sv[0]);
662 		(void)kern_close(td, sv[1]);
663 	}
664 	return (error);
665 }
666 
667 static int
668 sendit(struct thread *td, int s, struct msghdr *mp, int flags)
669 {
670 	struct mbuf *control;
671 	struct sockaddr *to;
672 	int error;
673 
674 #ifdef CAPABILITY_MODE
675 	if (IN_CAPABILITY_MODE(td) && (mp->msg_name != NULL))
676 		return (ECAPMODE);
677 #endif
678 
679 	if (mp->msg_name != NULL) {
680 		error = getsockaddr(&to, mp->msg_name, mp->msg_namelen);
681 		if (error != 0) {
682 			to = NULL;
683 			goto bad;
684 		}
685 		mp->msg_name = to;
686 	} else {
687 		to = NULL;
688 	}
689 
690 	if (mp->msg_control) {
691 		if (mp->msg_controllen < sizeof(struct cmsghdr)
692 #ifdef COMPAT_OLDSOCK
693 		    && (mp->msg_flags != MSG_COMPAT ||
694 		    !SV_PROC_FLAG(td->td_proc, SV_AOUT))
695 #endif
696 		) {
697 			error = EINVAL;
698 			goto bad;
699 		}
700 		error = sockargs(&control, mp->msg_control,
701 		    mp->msg_controllen, MT_CONTROL);
702 		if (error != 0)
703 			goto bad;
704 #ifdef COMPAT_OLDSOCK
705 		if (mp->msg_flags == MSG_COMPAT &&
706 		    SV_PROC_FLAG(td->td_proc, SV_AOUT)) {
707 			struct cmsghdr *cm;
708 
709 			M_PREPEND(control, sizeof(*cm), M_WAITOK);
710 			cm = mtod(control, struct cmsghdr *);
711 			cm->cmsg_len = control->m_len;
712 			cm->cmsg_level = SOL_SOCKET;
713 			cm->cmsg_type = SCM_RIGHTS;
714 		}
715 #endif
716 	} else {
717 		control = NULL;
718 	}
719 
720 	error = kern_sendit(td, s, mp, flags, control, UIO_USERSPACE);
721 
722 bad:
723 	free(to, M_SONAME);
724 	return (error);
725 }
726 
727 int
728 kern_sendit(struct thread *td, int s, struct msghdr *mp, int flags,
729     struct mbuf *control, enum uio_seg segflg)
730 {
731 	struct file *fp;
732 	struct uio auio;
733 	struct iovec *iov;
734 	struct socket *so;
735 	cap_rights_t *rights;
736 #ifdef KTRACE
737 	struct uio *ktruio = NULL;
738 #endif
739 	ssize_t len;
740 	int i, error;
741 
742 	AUDIT_ARG_FD(s);
743 	rights = &cap_send_rights;
744 	if (mp->msg_name != NULL) {
745 		AUDIT_ARG_SOCKADDR(td, AT_FDCWD, mp->msg_name);
746 		rights = &cap_send_connect_rights;
747 	}
748 	error = getsock_cap(td, s, rights, &fp, NULL, NULL);
749 	if (error != 0) {
750 		m_freem(control);
751 		return (error);
752 	}
753 	so = (struct socket *)fp->f_data;
754 
755 #ifdef KTRACE
756 	if (mp->msg_name != NULL && KTRPOINT(td, KTR_STRUCT))
757 		ktrsockaddr(mp->msg_name);
758 #endif
759 #ifdef MAC
760 	if (mp->msg_name != NULL) {
761 		error = mac_socket_check_connect(td->td_ucred, so,
762 		    mp->msg_name);
763 		if (error != 0) {
764 			m_freem(control);
765 			goto bad;
766 		}
767 	}
768 	error = mac_socket_check_send(td->td_ucred, so);
769 	if (error != 0) {
770 		m_freem(control);
771 		goto bad;
772 	}
773 #endif
774 
775 	auio.uio_iov = mp->msg_iov;
776 	auio.uio_iovcnt = mp->msg_iovlen;
777 	auio.uio_segflg = segflg;
778 	auio.uio_rw = UIO_WRITE;
779 	auio.uio_td = td;
780 	auio.uio_offset = 0;			/* XXX */
781 	auio.uio_resid = 0;
782 	iov = mp->msg_iov;
783 	for (i = 0; i < mp->msg_iovlen; i++, iov++) {
784 		if ((auio.uio_resid += iov->iov_len) < 0) {
785 			error = EINVAL;
786 			m_freem(control);
787 			goto bad;
788 		}
789 	}
790 #ifdef KTRACE
791 	if (KTRPOINT(td, KTR_GENIO))
792 		ktruio = cloneuio(&auio);
793 #endif
794 	len = auio.uio_resid;
795 	error = sosend(so, mp->msg_name, &auio, 0, control, flags, td);
796 	if (error != 0) {
797 		if (auio.uio_resid != len && (error == ERESTART ||
798 		    error == EINTR || error == EWOULDBLOCK))
799 			error = 0;
800 		/* Generation of SIGPIPE can be controlled per socket */
801 		if (error == EPIPE && !(so->so_options & SO_NOSIGPIPE) &&
802 		    !(flags & MSG_NOSIGNAL)) {
803 			PROC_LOCK(td->td_proc);
804 			tdsignal(td, SIGPIPE);
805 			PROC_UNLOCK(td->td_proc);
806 		}
807 	}
808 	if (error == 0)
809 		td->td_retval[0] = len - auio.uio_resid;
810 #ifdef KTRACE
811 	if (ktruio != NULL) {
812 		ktruio->uio_resid = td->td_retval[0];
813 		ktrgenio(s, UIO_WRITE, ktruio, error);
814 	}
815 #endif
816 bad:
817 	fdrop(fp, td);
818 	return (error);
819 }
820 
821 int
822 sys_sendto(struct thread *td, struct sendto_args *uap)
823 {
824 	struct msghdr msg;
825 	struct iovec aiov;
826 
827 	msg.msg_name = __DECONST(void *, uap->to);
828 	msg.msg_namelen = uap->tolen;
829 	msg.msg_iov = &aiov;
830 	msg.msg_iovlen = 1;
831 	msg.msg_control = 0;
832 #ifdef COMPAT_OLDSOCK
833 	if (SV_PROC_FLAG(td->td_proc, SV_AOUT))
834 		msg.msg_flags = 0;
835 #endif
836 	aiov.iov_base = __DECONST(void *, uap->buf);
837 	aiov.iov_len = uap->len;
838 	return (sendit(td, uap->s, &msg, uap->flags));
839 }
840 
841 #ifdef COMPAT_OLDSOCK
842 int
843 osend(struct thread *td, struct osend_args *uap)
844 {
845 	struct msghdr msg;
846 	struct iovec aiov;
847 
848 	msg.msg_name = 0;
849 	msg.msg_namelen = 0;
850 	msg.msg_iov = &aiov;
851 	msg.msg_iovlen = 1;
852 	aiov.iov_base = __DECONST(void *, uap->buf);
853 	aiov.iov_len = uap->len;
854 	msg.msg_control = 0;
855 	msg.msg_flags = 0;
856 	return (sendit(td, uap->s, &msg, uap->flags));
857 }
858 
859 int
860 osendmsg(struct thread *td, struct osendmsg_args *uap)
861 {
862 	struct msghdr msg;
863 	struct iovec *iov;
864 	int error;
865 
866 	error = copyin(uap->msg, &msg, sizeof (struct omsghdr));
867 	if (error != 0)
868 		return (error);
869 	error = copyiniov(msg.msg_iov, msg.msg_iovlen, &iov, EMSGSIZE);
870 	if (error != 0)
871 		return (error);
872 	msg.msg_iov = iov;
873 	msg.msg_flags = MSG_COMPAT;
874 	error = sendit(td, uap->s, &msg, uap->flags);
875 	free(iov, M_IOV);
876 	return (error);
877 }
878 #endif
879 
880 int
881 sys_sendmsg(struct thread *td, struct sendmsg_args *uap)
882 {
883 	struct msghdr msg;
884 	struct iovec *iov;
885 	int error;
886 
887 	error = copyin(uap->msg, &msg, sizeof (msg));
888 	if (error != 0)
889 		return (error);
890 	error = copyiniov(msg.msg_iov, msg.msg_iovlen, &iov, EMSGSIZE);
891 	if (error != 0)
892 		return (error);
893 	msg.msg_iov = iov;
894 #ifdef COMPAT_OLDSOCK
895 	if (SV_PROC_FLAG(td->td_proc, SV_AOUT))
896 		msg.msg_flags = 0;
897 #endif
898 	error = sendit(td, uap->s, &msg, uap->flags);
899 	free(iov, M_IOV);
900 	return (error);
901 }
902 
903 int
904 kern_recvit(struct thread *td, int s, struct msghdr *mp, enum uio_seg fromseg,
905     struct mbuf **controlp)
906 {
907 	struct uio auio;
908 	struct iovec *iov;
909 	struct mbuf *control, *m;
910 	caddr_t ctlbuf;
911 	struct file *fp;
912 	struct socket *so;
913 	struct sockaddr *fromsa = NULL;
914 #ifdef KTRACE
915 	struct uio *ktruio = NULL;
916 #endif
917 	ssize_t len;
918 	int error, i;
919 
920 	if (controlp != NULL)
921 		*controlp = NULL;
922 
923 	AUDIT_ARG_FD(s);
924 	error = getsock_cap(td, s, &cap_recv_rights,
925 	    &fp, NULL, NULL);
926 	if (error != 0)
927 		return (error);
928 	so = fp->f_data;
929 
930 #ifdef MAC
931 	error = mac_socket_check_receive(td->td_ucred, so);
932 	if (error != 0) {
933 		fdrop(fp, td);
934 		return (error);
935 	}
936 #endif
937 
938 	auio.uio_iov = mp->msg_iov;
939 	auio.uio_iovcnt = mp->msg_iovlen;
940 	auio.uio_segflg = UIO_USERSPACE;
941 	auio.uio_rw = UIO_READ;
942 	auio.uio_td = td;
943 	auio.uio_offset = 0;			/* XXX */
944 	auio.uio_resid = 0;
945 	iov = mp->msg_iov;
946 	for (i = 0; i < mp->msg_iovlen; i++, iov++) {
947 		if ((auio.uio_resid += iov->iov_len) < 0) {
948 			fdrop(fp, td);
949 			return (EINVAL);
950 		}
951 	}
952 #ifdef KTRACE
953 	if (KTRPOINT(td, KTR_GENIO))
954 		ktruio = cloneuio(&auio);
955 #endif
956 	control = NULL;
957 	len = auio.uio_resid;
958 	error = soreceive(so, &fromsa, &auio, NULL,
959 	    (mp->msg_control || controlp) ? &control : NULL,
960 	    &mp->msg_flags);
961 	if (error != 0) {
962 		if (auio.uio_resid != len && (error == ERESTART ||
963 		    error == EINTR || error == EWOULDBLOCK))
964 			error = 0;
965 	}
966 	if (fromsa != NULL)
967 		AUDIT_ARG_SOCKADDR(td, AT_FDCWD, fromsa);
968 #ifdef KTRACE
969 	if (ktruio != NULL) {
970 		ktruio->uio_resid = len - auio.uio_resid;
971 		ktrgenio(s, UIO_READ, ktruio, error);
972 	}
973 #endif
974 	if (error != 0)
975 		goto out;
976 	td->td_retval[0] = len - auio.uio_resid;
977 	if (mp->msg_name) {
978 		len = mp->msg_namelen;
979 		if (len <= 0 || fromsa == NULL)
980 			len = 0;
981 		else {
982 			/* save sa_len before it is destroyed by MSG_COMPAT */
983 			len = MIN(len, fromsa->sa_len);
984 #ifdef COMPAT_OLDSOCK
985 			if ((mp->msg_flags & MSG_COMPAT) != 0 &&
986 			    SV_PROC_FLAG(td->td_proc, SV_AOUT))
987 				((struct osockaddr *)fromsa)->sa_family =
988 				    fromsa->sa_family;
989 #endif
990 			if (fromseg == UIO_USERSPACE) {
991 				error = copyout(fromsa, mp->msg_name,
992 				    (unsigned)len);
993 				if (error != 0)
994 					goto out;
995 			} else
996 				bcopy(fromsa, mp->msg_name, len);
997 		}
998 		mp->msg_namelen = len;
999 	}
1000 	if (mp->msg_control && controlp == NULL) {
1001 #ifdef COMPAT_OLDSOCK
1002 		/*
1003 		 * We assume that old recvmsg calls won't receive access
1004 		 * rights and other control info, esp. as control info
1005 		 * is always optional and those options didn't exist in 4.3.
1006 		 * If we receive rights, trim the cmsghdr; anything else
1007 		 * is tossed.
1008 		 */
1009 		if (control && (mp->msg_flags & MSG_COMPAT) != 0 &&
1010 		    SV_PROC_FLAG(td->td_proc, SV_AOUT)) {
1011 			if (mtod(control, struct cmsghdr *)->cmsg_level !=
1012 			    SOL_SOCKET ||
1013 			    mtod(control, struct cmsghdr *)->cmsg_type !=
1014 			    SCM_RIGHTS) {
1015 				mp->msg_controllen = 0;
1016 				goto out;
1017 			}
1018 			control->m_len -= sizeof (struct cmsghdr);
1019 			control->m_data += sizeof (struct cmsghdr);
1020 		}
1021 #endif
1022 		ctlbuf = mp->msg_control;
1023 		len = mp->msg_controllen;
1024 		mp->msg_controllen = 0;
1025 		for (m = control; m != NULL && len >= m->m_len; m = m->m_next) {
1026 			if ((error = copyout(mtod(m, caddr_t), ctlbuf,
1027 			    m->m_len)) != 0)
1028 				goto out;
1029 
1030 			ctlbuf += m->m_len;
1031 			len -= m->m_len;
1032 			mp->msg_controllen += m->m_len;
1033 		}
1034 		if (m != NULL) {
1035 			mp->msg_flags |= MSG_CTRUNC;
1036 			m_dispose_extcontrolm(m);
1037 		}
1038 	}
1039 out:
1040 	fdrop(fp, td);
1041 #ifdef KTRACE
1042 	if (fromsa && KTRPOINT(td, KTR_STRUCT))
1043 		ktrsockaddr(fromsa);
1044 #endif
1045 	free(fromsa, M_SONAME);
1046 
1047 	if (error == 0 && controlp != NULL)
1048 		*controlp = control;
1049 	else if (control != NULL) {
1050 		if (error != 0)
1051 			m_dispose_extcontrolm(control);
1052 		m_freem(control);
1053 	}
1054 
1055 	return (error);
1056 }
1057 
1058 static int
1059 recvit(struct thread *td, int s, struct msghdr *mp, void *namelenp)
1060 {
1061 	int error;
1062 
1063 	error = kern_recvit(td, s, mp, UIO_USERSPACE, NULL);
1064 	if (error != 0)
1065 		return (error);
1066 	if (namelenp != NULL) {
1067 		error = copyout(&mp->msg_namelen, namelenp, sizeof (socklen_t));
1068 #ifdef COMPAT_OLDSOCK
1069 		if ((mp->msg_flags & MSG_COMPAT) != 0 &&
1070 		    SV_PROC_FLAG(td->td_proc, SV_AOUT))
1071 			error = 0;	/* old recvfrom didn't check */
1072 #endif
1073 	}
1074 	return (error);
1075 }
1076 
1077 int
1078 sys_recvfrom(struct thread *td, struct recvfrom_args *uap)
1079 {
1080 	struct msghdr msg;
1081 	struct iovec aiov;
1082 	int error;
1083 
1084 	if (uap->fromlenaddr) {
1085 		error = copyin(uap->fromlenaddr,
1086 		    &msg.msg_namelen, sizeof (msg.msg_namelen));
1087 		if (error != 0)
1088 			goto done2;
1089 	} else {
1090 		msg.msg_namelen = 0;
1091 	}
1092 	msg.msg_name = uap->from;
1093 	msg.msg_iov = &aiov;
1094 	msg.msg_iovlen = 1;
1095 	aiov.iov_base = uap->buf;
1096 	aiov.iov_len = uap->len;
1097 	msg.msg_control = 0;
1098 	msg.msg_flags = uap->flags;
1099 	error = recvit(td, uap->s, &msg, uap->fromlenaddr);
1100 done2:
1101 	return (error);
1102 }
1103 
1104 #ifdef COMPAT_OLDSOCK
1105 int
1106 orecvfrom(struct thread *td, struct recvfrom_args *uap)
1107 {
1108 
1109 	uap->flags |= MSG_COMPAT;
1110 	return (sys_recvfrom(td, uap));
1111 }
1112 #endif
1113 
1114 #ifdef COMPAT_OLDSOCK
1115 int
1116 orecv(struct thread *td, struct orecv_args *uap)
1117 {
1118 	struct msghdr msg;
1119 	struct iovec aiov;
1120 
1121 	msg.msg_name = 0;
1122 	msg.msg_namelen = 0;
1123 	msg.msg_iov = &aiov;
1124 	msg.msg_iovlen = 1;
1125 	aiov.iov_base = uap->buf;
1126 	aiov.iov_len = uap->len;
1127 	msg.msg_control = 0;
1128 	msg.msg_flags = uap->flags;
1129 	return (recvit(td, uap->s, &msg, NULL));
1130 }
1131 
1132 /*
1133  * Old recvmsg.  This code takes advantage of the fact that the old msghdr
1134  * overlays the new one, missing only the flags, and with the (old) access
1135  * rights where the control fields are now.
1136  */
1137 int
1138 orecvmsg(struct thread *td, struct orecvmsg_args *uap)
1139 {
1140 	struct msghdr msg;
1141 	struct iovec *iov;
1142 	int error;
1143 
1144 	error = copyin(uap->msg, &msg, sizeof (struct omsghdr));
1145 	if (error != 0)
1146 		return (error);
1147 	error = copyiniov(msg.msg_iov, msg.msg_iovlen, &iov, EMSGSIZE);
1148 	if (error != 0)
1149 		return (error);
1150 	msg.msg_flags = uap->flags | MSG_COMPAT;
1151 	msg.msg_iov = iov;
1152 	error = recvit(td, uap->s, &msg, &uap->msg->msg_namelen);
1153 	if (msg.msg_controllen && error == 0)
1154 		error = copyout(&msg.msg_controllen,
1155 		    &uap->msg->msg_accrightslen, sizeof (int));
1156 	free(iov, M_IOV);
1157 	return (error);
1158 }
1159 #endif
1160 
1161 int
1162 sys_recvmsg(struct thread *td, struct recvmsg_args *uap)
1163 {
1164 	struct msghdr msg;
1165 	struct iovec *uiov, *iov;
1166 	int error;
1167 
1168 	error = copyin(uap->msg, &msg, sizeof (msg));
1169 	if (error != 0)
1170 		return (error);
1171 	error = copyiniov(msg.msg_iov, msg.msg_iovlen, &iov, EMSGSIZE);
1172 	if (error != 0)
1173 		return (error);
1174 	msg.msg_flags = uap->flags;
1175 #ifdef COMPAT_OLDSOCK
1176 	if (SV_PROC_FLAG(td->td_proc, SV_AOUT))
1177 		msg.msg_flags &= ~MSG_COMPAT;
1178 #endif
1179 	uiov = msg.msg_iov;
1180 	msg.msg_iov = iov;
1181 	error = recvit(td, uap->s, &msg, NULL);
1182 	if (error == 0) {
1183 		msg.msg_iov = uiov;
1184 		error = copyout(&msg, uap->msg, sizeof(msg));
1185 	}
1186 	free(iov, M_IOV);
1187 	return (error);
1188 }
1189 
1190 int
1191 sys_shutdown(struct thread *td, struct shutdown_args *uap)
1192 {
1193 
1194 	return (kern_shutdown(td, uap->s, uap->how));
1195 }
1196 
1197 int
1198 kern_shutdown(struct thread *td, int s, int how)
1199 {
1200 	struct socket *so;
1201 	struct file *fp;
1202 	int error;
1203 
1204 	AUDIT_ARG_FD(s);
1205 	error = getsock_cap(td, s, &cap_shutdown_rights,
1206 	    &fp, NULL, NULL);
1207 	if (error == 0) {
1208 		so = fp->f_data;
1209 		error = soshutdown(so, how);
1210 		/*
1211 		 * Previous versions did not return ENOTCONN, but 0 in
1212 		 * case the socket was not connected. Some important
1213 		 * programs like syslogd up to r279016, 2015-02-19,
1214 		 * still depend on this behavior.
1215 		 */
1216 		if (error == ENOTCONN &&
1217 		    td->td_proc->p_osrel < P_OSREL_SHUTDOWN_ENOTCONN)
1218 			error = 0;
1219 		fdrop(fp, td);
1220 	}
1221 	return (error);
1222 }
1223 
1224 int
1225 sys_setsockopt(struct thread *td, struct setsockopt_args *uap)
1226 {
1227 
1228 	return (kern_setsockopt(td, uap->s, uap->level, uap->name,
1229 	    uap->val, UIO_USERSPACE, uap->valsize));
1230 }
1231 
1232 int
1233 kern_setsockopt(struct thread *td, int s, int level, int name, const void *val,
1234     enum uio_seg valseg, socklen_t valsize)
1235 {
1236 	struct socket *so;
1237 	struct file *fp;
1238 	struct sockopt sopt;
1239 	int error;
1240 
1241 	if (val == NULL && valsize != 0)
1242 		return (EFAULT);
1243 	if ((int)valsize < 0)
1244 		return (EINVAL);
1245 
1246 	sopt.sopt_dir = SOPT_SET;
1247 	sopt.sopt_level = level;
1248 	sopt.sopt_name = name;
1249 	sopt.sopt_val = __DECONST(void *, val);
1250 	sopt.sopt_valsize = valsize;
1251 	switch (valseg) {
1252 	case UIO_USERSPACE:
1253 		sopt.sopt_td = td;
1254 		break;
1255 	case UIO_SYSSPACE:
1256 		sopt.sopt_td = NULL;
1257 		break;
1258 	default:
1259 		panic("kern_setsockopt called with bad valseg");
1260 	}
1261 
1262 	AUDIT_ARG_FD(s);
1263 	error = getsock_cap(td, s, &cap_setsockopt_rights,
1264 	    &fp, NULL, NULL);
1265 	if (error == 0) {
1266 		so = fp->f_data;
1267 		error = sosetopt(so, &sopt);
1268 		fdrop(fp, td);
1269 	}
1270 	return(error);
1271 }
1272 
1273 int
1274 sys_getsockopt(struct thread *td, struct getsockopt_args *uap)
1275 {
1276 	socklen_t valsize;
1277 	int error;
1278 
1279 	if (uap->val) {
1280 		error = copyin(uap->avalsize, &valsize, sizeof (valsize));
1281 		if (error != 0)
1282 			return (error);
1283 	}
1284 
1285 	error = kern_getsockopt(td, uap->s, uap->level, uap->name,
1286 	    uap->val, UIO_USERSPACE, &valsize);
1287 
1288 	if (error == 0)
1289 		error = copyout(&valsize, uap->avalsize, sizeof (valsize));
1290 	return (error);
1291 }
1292 
1293 /*
1294  * Kernel version of getsockopt.
1295  * optval can be a userland or userspace. optlen is always a kernel pointer.
1296  */
1297 int
1298 kern_getsockopt(struct thread *td, int s, int level, int name, void *val,
1299     enum uio_seg valseg, socklen_t *valsize)
1300 {
1301 	struct socket *so;
1302 	struct file *fp;
1303 	struct sockopt sopt;
1304 	int error;
1305 
1306 	if (val == NULL)
1307 		*valsize = 0;
1308 	if ((int)*valsize < 0)
1309 		return (EINVAL);
1310 
1311 	sopt.sopt_dir = SOPT_GET;
1312 	sopt.sopt_level = level;
1313 	sopt.sopt_name = name;
1314 	sopt.sopt_val = val;
1315 	sopt.sopt_valsize = (size_t)*valsize; /* checked non-negative above */
1316 	switch (valseg) {
1317 	case UIO_USERSPACE:
1318 		sopt.sopt_td = td;
1319 		break;
1320 	case UIO_SYSSPACE:
1321 		sopt.sopt_td = NULL;
1322 		break;
1323 	default:
1324 		panic("kern_getsockopt called with bad valseg");
1325 	}
1326 
1327 	AUDIT_ARG_FD(s);
1328 	error = getsock_cap(td, s, &cap_getsockopt_rights,
1329 	    &fp, NULL, NULL);
1330 	if (error == 0) {
1331 		so = fp->f_data;
1332 		error = sogetopt(so, &sopt);
1333 		*valsize = sopt.sopt_valsize;
1334 		fdrop(fp, td);
1335 	}
1336 	return (error);
1337 }
1338 
1339 /*
1340  * getsockname1() - Get socket name.
1341  */
1342 static int
1343 getsockname1(struct thread *td, struct getsockname_args *uap, int compat)
1344 {
1345 	struct sockaddr *sa;
1346 	socklen_t len;
1347 	int error;
1348 
1349 	error = copyin(uap->alen, &len, sizeof(len));
1350 	if (error != 0)
1351 		return (error);
1352 
1353 	error = kern_getsockname(td, uap->fdes, &sa, &len);
1354 	if (error != 0)
1355 		return (error);
1356 
1357 	if (len != 0) {
1358 #ifdef COMPAT_OLDSOCK
1359 		if (compat && SV_PROC_FLAG(td->td_proc, SV_AOUT))
1360 			((struct osockaddr *)sa)->sa_family = sa->sa_family;
1361 #endif
1362 		error = copyout(sa, uap->asa, (u_int)len);
1363 	}
1364 	free(sa, M_SONAME);
1365 	if (error == 0)
1366 		error = copyout(&len, uap->alen, sizeof(len));
1367 	return (error);
1368 }
1369 
1370 int
1371 kern_getsockname(struct thread *td, int fd, struct sockaddr **sa,
1372     socklen_t *alen)
1373 {
1374 	struct socket *so;
1375 	struct file *fp;
1376 	socklen_t len;
1377 	int error;
1378 
1379 	AUDIT_ARG_FD(fd);
1380 	error = getsock_cap(td, fd, &cap_getsockname_rights,
1381 	    &fp, NULL, NULL);
1382 	if (error != 0)
1383 		return (error);
1384 	so = fp->f_data;
1385 	*sa = NULL;
1386 	CURVNET_SET(so->so_vnet);
1387 	error = (*so->so_proto->pr_usrreqs->pru_sockaddr)(so, sa);
1388 	CURVNET_RESTORE();
1389 	if (error != 0)
1390 		goto bad;
1391 	if (*sa == NULL)
1392 		len = 0;
1393 	else
1394 		len = MIN(*alen, (*sa)->sa_len);
1395 	*alen = len;
1396 #ifdef KTRACE
1397 	if (KTRPOINT(td, KTR_STRUCT))
1398 		ktrsockaddr(*sa);
1399 #endif
1400 bad:
1401 	fdrop(fp, td);
1402 	if (error != 0 && *sa != NULL) {
1403 		free(*sa, M_SONAME);
1404 		*sa = NULL;
1405 	}
1406 	return (error);
1407 }
1408 
1409 int
1410 sys_getsockname(struct thread *td, struct getsockname_args *uap)
1411 {
1412 
1413 	return (getsockname1(td, uap, 0));
1414 }
1415 
1416 #ifdef COMPAT_OLDSOCK
1417 int
1418 ogetsockname(struct thread *td, struct getsockname_args *uap)
1419 {
1420 
1421 	return (getsockname1(td, uap, 1));
1422 }
1423 #endif /* COMPAT_OLDSOCK */
1424 
1425 /*
1426  * getpeername1() - Get name of peer for connected socket.
1427  */
1428 static int
1429 getpeername1(struct thread *td, struct getpeername_args *uap, int compat)
1430 {
1431 	struct sockaddr *sa;
1432 	socklen_t len;
1433 	int error;
1434 
1435 	error = copyin(uap->alen, &len, sizeof (len));
1436 	if (error != 0)
1437 		return (error);
1438 
1439 	error = kern_getpeername(td, uap->fdes, &sa, &len);
1440 	if (error != 0)
1441 		return (error);
1442 
1443 	if (len != 0) {
1444 #ifdef COMPAT_OLDSOCK
1445 		if (compat && SV_PROC_FLAG(td->td_proc, SV_AOUT))
1446 			((struct osockaddr *)sa)->sa_family = sa->sa_family;
1447 #endif
1448 		error = copyout(sa, uap->asa, (u_int)len);
1449 	}
1450 	free(sa, M_SONAME);
1451 	if (error == 0)
1452 		error = copyout(&len, uap->alen, sizeof(len));
1453 	return (error);
1454 }
1455 
1456 int
1457 kern_getpeername(struct thread *td, int fd, struct sockaddr **sa,
1458     socklen_t *alen)
1459 {
1460 	struct socket *so;
1461 	struct file *fp;
1462 	socklen_t len;
1463 	int error;
1464 
1465 	AUDIT_ARG_FD(fd);
1466 	error = getsock_cap(td, fd, &cap_getpeername_rights,
1467 	    &fp, NULL, NULL);
1468 	if (error != 0)
1469 		return (error);
1470 	so = fp->f_data;
1471 	if ((so->so_state & (SS_ISCONNECTED|SS_ISCONFIRMING)) == 0) {
1472 		error = ENOTCONN;
1473 		goto done;
1474 	}
1475 	*sa = NULL;
1476 	CURVNET_SET(so->so_vnet);
1477 	error = (*so->so_proto->pr_usrreqs->pru_peeraddr)(so, sa);
1478 	CURVNET_RESTORE();
1479 	if (error != 0)
1480 		goto bad;
1481 	if (*sa == NULL)
1482 		len = 0;
1483 	else
1484 		len = MIN(*alen, (*sa)->sa_len);
1485 	*alen = len;
1486 #ifdef KTRACE
1487 	if (KTRPOINT(td, KTR_STRUCT))
1488 		ktrsockaddr(*sa);
1489 #endif
1490 bad:
1491 	if (error != 0 && *sa != NULL) {
1492 		free(*sa, M_SONAME);
1493 		*sa = NULL;
1494 	}
1495 done:
1496 	fdrop(fp, td);
1497 	return (error);
1498 }
1499 
1500 int
1501 sys_getpeername(struct thread *td, struct getpeername_args *uap)
1502 {
1503 
1504 	return (getpeername1(td, uap, 0));
1505 }
1506 
1507 #ifdef COMPAT_OLDSOCK
1508 int
1509 ogetpeername(struct thread *td, struct ogetpeername_args *uap)
1510 {
1511 
1512 	/* XXX uap should have type `getpeername_args *' to begin with. */
1513 	return (getpeername1(td, (struct getpeername_args *)uap, 1));
1514 }
1515 #endif /* COMPAT_OLDSOCK */
1516 
1517 static int
1518 sockargs(struct mbuf **mp, char *buf, socklen_t buflen, int type)
1519 {
1520 	struct sockaddr *sa;
1521 	struct mbuf *m;
1522 	int error;
1523 
1524 	if (buflen > MLEN) {
1525 #ifdef COMPAT_OLDSOCK
1526 		if (type == MT_SONAME && buflen <= 112 &&
1527 		    SV_CURPROC_FLAG(SV_AOUT))
1528 			buflen = MLEN;		/* unix domain compat. hack */
1529 		else
1530 #endif
1531 			if (buflen > MCLBYTES)
1532 				return (EINVAL);
1533 	}
1534 	m = m_get2(buflen, M_WAITOK, type, 0);
1535 	m->m_len = buflen;
1536 	error = copyin(buf, mtod(m, void *), buflen);
1537 	if (error != 0)
1538 		(void) m_free(m);
1539 	else {
1540 		*mp = m;
1541 		if (type == MT_SONAME) {
1542 			sa = mtod(m, struct sockaddr *);
1543 
1544 #if defined(COMPAT_OLDSOCK) && BYTE_ORDER != BIG_ENDIAN
1545 			if (sa->sa_family == 0 && sa->sa_len < AF_MAX &&
1546 			    SV_CURPROC_FLAG(SV_AOUT))
1547 				sa->sa_family = sa->sa_len;
1548 #endif
1549 			sa->sa_len = buflen;
1550 		}
1551 	}
1552 	return (error);
1553 }
1554 
1555 int
1556 getsockaddr(struct sockaddr **namp, const struct sockaddr *uaddr, size_t len)
1557 {
1558 	struct sockaddr *sa;
1559 	int error;
1560 
1561 	if (len > SOCK_MAXADDRLEN)
1562 		return (ENAMETOOLONG);
1563 	if (len < offsetof(struct sockaddr, sa_data[0]))
1564 		return (EINVAL);
1565 	sa = malloc(len, M_SONAME, M_WAITOK);
1566 	error = copyin(uaddr, sa, len);
1567 	if (error != 0) {
1568 		free(sa, M_SONAME);
1569 	} else {
1570 #if defined(COMPAT_OLDSOCK) && BYTE_ORDER != BIG_ENDIAN
1571 		if (sa->sa_family == 0 && sa->sa_len < AF_MAX &&
1572 		    SV_CURPROC_FLAG(SV_AOUT))
1573 			sa->sa_family = sa->sa_len;
1574 #endif
1575 		sa->sa_len = len;
1576 		*namp = sa;
1577 	}
1578 	return (error);
1579 }
1580 
1581 /*
1582  * Dispose of externalized rights from an SCM_RIGHTS message.  This function
1583  * should be used in error or truncation cases to avoid leaking file descriptors
1584  * into the recipient's (the current thread's) table.
1585  */
1586 void
1587 m_dispose_extcontrolm(struct mbuf *m)
1588 {
1589 	struct cmsghdr *cm;
1590 	struct file *fp;
1591 	struct thread *td;
1592 	socklen_t clen, datalen;
1593 	int error, fd, *fds, nfd;
1594 
1595 	td = curthread;
1596 	for (; m != NULL; m = m->m_next) {
1597 		if (m->m_type != MT_EXTCONTROL)
1598 			continue;
1599 		cm = mtod(m, struct cmsghdr *);
1600 		clen = m->m_len;
1601 		while (clen > 0) {
1602 			if (clen < sizeof(*cm))
1603 				panic("%s: truncated mbuf %p", __func__, m);
1604 			datalen = CMSG_SPACE(cm->cmsg_len - CMSG_SPACE(0));
1605 			if (clen < datalen)
1606 				panic("%s: truncated mbuf %p", __func__, m);
1607 
1608 			if (cm->cmsg_level == SOL_SOCKET &&
1609 			    cm->cmsg_type == SCM_RIGHTS) {
1610 				fds = (int *)CMSG_DATA(cm);
1611 				nfd = (cm->cmsg_len - CMSG_SPACE(0)) /
1612 				    sizeof(int);
1613 
1614 				while (nfd-- > 0) {
1615 					fd = *fds++;
1616 					error = fget(td, fd, &cap_no_rights,
1617 					    &fp);
1618 					if (error == 0) {
1619 						fdclose(td, fp, fd);
1620 						fdrop(fp, td);
1621 					}
1622 				}
1623 			}
1624 			clen -= datalen;
1625 			cm = (struct cmsghdr *)((uint8_t *)cm + datalen);
1626 		}
1627 		m_chtype(m, MT_CONTROL);
1628 	}
1629 }
1630