xref: /freebsd/sys/kern/uipc_syscalls.c (revision b0d29bc47dba79f6f38e67eabadfb4b32ffd9390)
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 ((head->so_options & SO_ACCEPTCONN) == 0) {
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 	if (dirfd == AT_FDCWD)
515 		error = soconnect(so, sa, td);
516 	else
517 		error = soconnectat(dirfd, so, sa, td);
518 	if (error != 0)
519 		goto bad;
520 	if ((so->so_state & SS_NBIO) && (so->so_state & SS_ISCONNECTING)) {
521 		error = EINPROGRESS;
522 		goto done1;
523 	}
524 	SOCK_LOCK(so);
525 	while ((so->so_state & SS_ISCONNECTING) && so->so_error == 0) {
526 		error = msleep(&so->so_timeo, &so->so_lock, PSOCK | PCATCH,
527 		    "connec", 0);
528 		if (error != 0) {
529 			if (error == EINTR || error == ERESTART)
530 				interrupted = 1;
531 			break;
532 		}
533 	}
534 	if (error == 0) {
535 		error = so->so_error;
536 		so->so_error = 0;
537 	}
538 	SOCK_UNLOCK(so);
539 bad:
540 	if (!interrupted)
541 		so->so_state &= ~SS_ISCONNECTING;
542 	if (error == ERESTART)
543 		error = EINTR;
544 done1:
545 	fdrop(fp, td);
546 	return (error);
547 }
548 
549 int
550 sys_connectat(struct thread *td, struct connectat_args *uap)
551 {
552 	struct sockaddr *sa;
553 	int error;
554 
555 	error = getsockaddr(&sa, uap->name, uap->namelen);
556 	if (error == 0) {
557 		error = kern_connectat(td, uap->fd, uap->s, sa);
558 		free(sa, M_SONAME);
559 	}
560 	return (error);
561 }
562 
563 int
564 kern_socketpair(struct thread *td, int domain, int type, int protocol,
565     int *rsv)
566 {
567 	struct file *fp1, *fp2;
568 	struct socket *so1, *so2;
569 	int fd, error, oflag, fflag;
570 
571 	AUDIT_ARG_SOCKET(domain, type, protocol);
572 
573 	oflag = 0;
574 	fflag = 0;
575 	if ((type & SOCK_CLOEXEC) != 0) {
576 		type &= ~SOCK_CLOEXEC;
577 		oflag |= O_CLOEXEC;
578 	}
579 	if ((type & SOCK_NONBLOCK) != 0) {
580 		type &= ~SOCK_NONBLOCK;
581 		fflag |= FNONBLOCK;
582 	}
583 #ifdef MAC
584 	/* We might want to have a separate check for socket pairs. */
585 	error = mac_socket_check_create(td->td_ucred, domain, type,
586 	    protocol);
587 	if (error != 0)
588 		return (error);
589 #endif
590 	error = socreate(domain, &so1, type, protocol, td->td_ucred, td);
591 	if (error != 0)
592 		return (error);
593 	error = socreate(domain, &so2, type, protocol, td->td_ucred, td);
594 	if (error != 0)
595 		goto free1;
596 	/* On success extra reference to `fp1' and 'fp2' is set by falloc. */
597 	error = falloc(td, &fp1, &fd, oflag);
598 	if (error != 0)
599 		goto free2;
600 	rsv[0] = fd;
601 	fp1->f_data = so1;	/* so1 already has ref count */
602 	error = falloc(td, &fp2, &fd, oflag);
603 	if (error != 0)
604 		goto free3;
605 	fp2->f_data = so2;	/* so2 already has ref count */
606 	rsv[1] = fd;
607 	error = soconnect2(so1, so2);
608 	if (error != 0)
609 		goto free4;
610 	if (type == SOCK_DGRAM) {
611 		/*
612 		 * Datagram socket connection is asymmetric.
613 		 */
614 		 error = soconnect2(so2, so1);
615 		 if (error != 0)
616 			goto free4;
617 	} else if (so1->so_proto->pr_flags & PR_CONNREQUIRED) {
618 		struct unpcb *unp, *unp2;
619 		unp = sotounpcb(so1);
620 		unp2 = sotounpcb(so2);
621 		/*
622 		 * No need to lock the unps, because the sockets are brand-new.
623 		 * No other threads can be using them yet
624 		 */
625 		unp_copy_peercred(td, unp, unp2, unp);
626 	}
627 	finit(fp1, FREAD | FWRITE | fflag, DTYPE_SOCKET, fp1->f_data,
628 	    &socketops);
629 	finit(fp2, FREAD | FWRITE | fflag, DTYPE_SOCKET, fp2->f_data,
630 	    &socketops);
631 	if ((fflag & FNONBLOCK) != 0) {
632 		(void) fo_ioctl(fp1, FIONBIO, &fflag, td->td_ucred, td);
633 		(void) fo_ioctl(fp2, FIONBIO, &fflag, td->td_ucred, td);
634 	}
635 	fdrop(fp1, td);
636 	fdrop(fp2, td);
637 	return (0);
638 free4:
639 	fdclose(td, fp2, rsv[1]);
640 	fdrop(fp2, td);
641 free3:
642 	fdclose(td, fp1, rsv[0]);
643 	fdrop(fp1, td);
644 free2:
645 	if (so2 != NULL)
646 		(void)soclose(so2);
647 free1:
648 	if (so1 != NULL)
649 		(void)soclose(so1);
650 	return (error);
651 }
652 
653 int
654 sys_socketpair(struct thread *td, struct socketpair_args *uap)
655 {
656 	int error, sv[2];
657 
658 	error = kern_socketpair(td, uap->domain, uap->type,
659 	    uap->protocol, sv);
660 	if (error != 0)
661 		return (error);
662 	error = copyout(sv, uap->rsv, 2 * sizeof(int));
663 	if (error != 0) {
664 		(void)kern_close(td, sv[0]);
665 		(void)kern_close(td, sv[1]);
666 	}
667 	return (error);
668 }
669 
670 static int
671 sendit(struct thread *td, int s, struct msghdr *mp, int flags)
672 {
673 	struct mbuf *control;
674 	struct sockaddr *to;
675 	int error;
676 
677 #ifdef CAPABILITY_MODE
678 	if (IN_CAPABILITY_MODE(td) && (mp->msg_name != NULL))
679 		return (ECAPMODE);
680 #endif
681 
682 	if (mp->msg_name != NULL) {
683 		error = getsockaddr(&to, mp->msg_name, mp->msg_namelen);
684 		if (error != 0) {
685 			to = NULL;
686 			goto bad;
687 		}
688 		mp->msg_name = to;
689 	} else {
690 		to = NULL;
691 	}
692 
693 	if (mp->msg_control) {
694 		if (mp->msg_controllen < sizeof(struct cmsghdr)
695 #ifdef COMPAT_OLDSOCK
696 		    && (mp->msg_flags != MSG_COMPAT ||
697 		    !SV_PROC_FLAG(td->td_proc, SV_AOUT))
698 #endif
699 		) {
700 			error = EINVAL;
701 			goto bad;
702 		}
703 		error = sockargs(&control, mp->msg_control,
704 		    mp->msg_controllen, MT_CONTROL);
705 		if (error != 0)
706 			goto bad;
707 #ifdef COMPAT_OLDSOCK
708 		if (mp->msg_flags == MSG_COMPAT &&
709 		    SV_PROC_FLAG(td->td_proc, SV_AOUT)) {
710 			struct cmsghdr *cm;
711 
712 			M_PREPEND(control, sizeof(*cm), M_WAITOK);
713 			cm = mtod(control, struct cmsghdr *);
714 			cm->cmsg_len = control->m_len;
715 			cm->cmsg_level = SOL_SOCKET;
716 			cm->cmsg_type = SCM_RIGHTS;
717 		}
718 #endif
719 	} else {
720 		control = NULL;
721 	}
722 
723 	error = kern_sendit(td, s, mp, flags, control, UIO_USERSPACE);
724 
725 bad:
726 	free(to, M_SONAME);
727 	return (error);
728 }
729 
730 int
731 kern_sendit(struct thread *td, int s, struct msghdr *mp, int flags,
732     struct mbuf *control, enum uio_seg segflg)
733 {
734 	struct file *fp;
735 	struct uio auio;
736 	struct iovec *iov;
737 	struct socket *so;
738 	cap_rights_t *rights;
739 #ifdef KTRACE
740 	struct uio *ktruio = NULL;
741 #endif
742 	ssize_t len;
743 	int i, error;
744 
745 	AUDIT_ARG_FD(s);
746 	rights = &cap_send_rights;
747 	if (mp->msg_name != NULL) {
748 		AUDIT_ARG_SOCKADDR(td, AT_FDCWD, mp->msg_name);
749 		rights = &cap_send_connect_rights;
750 	}
751 	error = getsock_cap(td, s, rights, &fp, NULL, NULL);
752 	if (error != 0) {
753 		m_freem(control);
754 		return (error);
755 	}
756 	so = (struct socket *)fp->f_data;
757 
758 #ifdef KTRACE
759 	if (mp->msg_name != NULL && KTRPOINT(td, KTR_STRUCT))
760 		ktrsockaddr(mp->msg_name);
761 #endif
762 #ifdef MAC
763 	if (mp->msg_name != NULL) {
764 		error = mac_socket_check_connect(td->td_ucred, so,
765 		    mp->msg_name);
766 		if (error != 0) {
767 			m_freem(control);
768 			goto bad;
769 		}
770 	}
771 	error = mac_socket_check_send(td->td_ucred, so);
772 	if (error != 0) {
773 		m_freem(control);
774 		goto bad;
775 	}
776 #endif
777 
778 	auio.uio_iov = mp->msg_iov;
779 	auio.uio_iovcnt = mp->msg_iovlen;
780 	auio.uio_segflg = segflg;
781 	auio.uio_rw = UIO_WRITE;
782 	auio.uio_td = td;
783 	auio.uio_offset = 0;			/* XXX */
784 	auio.uio_resid = 0;
785 	iov = mp->msg_iov;
786 	for (i = 0; i < mp->msg_iovlen; i++, iov++) {
787 		if ((auio.uio_resid += iov->iov_len) < 0) {
788 			error = EINVAL;
789 			m_freem(control);
790 			goto bad;
791 		}
792 	}
793 #ifdef KTRACE
794 	if (KTRPOINT(td, KTR_GENIO))
795 		ktruio = cloneuio(&auio);
796 #endif
797 	len = auio.uio_resid;
798 	error = sosend(so, mp->msg_name, &auio, 0, control, flags, td);
799 	if (error != 0) {
800 		if (auio.uio_resid != len && (error == ERESTART ||
801 		    error == EINTR || error == EWOULDBLOCK))
802 			error = 0;
803 		/* Generation of SIGPIPE can be controlled per socket */
804 		if (error == EPIPE && !(so->so_options & SO_NOSIGPIPE) &&
805 		    !(flags & MSG_NOSIGNAL)) {
806 			PROC_LOCK(td->td_proc);
807 			tdsignal(td, SIGPIPE);
808 			PROC_UNLOCK(td->td_proc);
809 		}
810 	}
811 	if (error == 0)
812 		td->td_retval[0] = len - auio.uio_resid;
813 #ifdef KTRACE
814 	if (ktruio != NULL) {
815 		ktruio->uio_resid = td->td_retval[0];
816 		ktrgenio(s, UIO_WRITE, ktruio, error);
817 	}
818 #endif
819 bad:
820 	fdrop(fp, td);
821 	return (error);
822 }
823 
824 int
825 sys_sendto(struct thread *td, struct sendto_args *uap)
826 {
827 	struct msghdr msg;
828 	struct iovec aiov;
829 
830 	msg.msg_name = __DECONST(void *, uap->to);
831 	msg.msg_namelen = uap->tolen;
832 	msg.msg_iov = &aiov;
833 	msg.msg_iovlen = 1;
834 	msg.msg_control = 0;
835 #ifdef COMPAT_OLDSOCK
836 	if (SV_PROC_FLAG(td->td_proc, SV_AOUT))
837 		msg.msg_flags = 0;
838 #endif
839 	aiov.iov_base = __DECONST(void *, uap->buf);
840 	aiov.iov_len = uap->len;
841 	return (sendit(td, uap->s, &msg, uap->flags));
842 }
843 
844 #ifdef COMPAT_OLDSOCK
845 int
846 osend(struct thread *td, struct osend_args *uap)
847 {
848 	struct msghdr msg;
849 	struct iovec aiov;
850 
851 	msg.msg_name = 0;
852 	msg.msg_namelen = 0;
853 	msg.msg_iov = &aiov;
854 	msg.msg_iovlen = 1;
855 	aiov.iov_base = __DECONST(void *, uap->buf);
856 	aiov.iov_len = uap->len;
857 	msg.msg_control = 0;
858 	msg.msg_flags = 0;
859 	return (sendit(td, uap->s, &msg, uap->flags));
860 }
861 
862 int
863 osendmsg(struct thread *td, struct osendmsg_args *uap)
864 {
865 	struct msghdr msg;
866 	struct iovec *iov;
867 	int error;
868 
869 	error = copyin(uap->msg, &msg, sizeof (struct omsghdr));
870 	if (error != 0)
871 		return (error);
872 	error = copyiniov(msg.msg_iov, msg.msg_iovlen, &iov, EMSGSIZE);
873 	if (error != 0)
874 		return (error);
875 	msg.msg_iov = iov;
876 	msg.msg_flags = MSG_COMPAT;
877 	error = sendit(td, uap->s, &msg, uap->flags);
878 	free(iov, M_IOV);
879 	return (error);
880 }
881 #endif
882 
883 int
884 sys_sendmsg(struct thread *td, struct sendmsg_args *uap)
885 {
886 	struct msghdr msg;
887 	struct iovec *iov;
888 	int error;
889 
890 	error = copyin(uap->msg, &msg, sizeof (msg));
891 	if (error != 0)
892 		return (error);
893 	error = copyiniov(msg.msg_iov, msg.msg_iovlen, &iov, EMSGSIZE);
894 	if (error != 0)
895 		return (error);
896 	msg.msg_iov = iov;
897 #ifdef COMPAT_OLDSOCK
898 	if (SV_PROC_FLAG(td->td_proc, SV_AOUT))
899 		msg.msg_flags = 0;
900 #endif
901 	error = sendit(td, uap->s, &msg, uap->flags);
902 	free(iov, M_IOV);
903 	return (error);
904 }
905 
906 int
907 kern_recvit(struct thread *td, int s, struct msghdr *mp, enum uio_seg fromseg,
908     struct mbuf **controlp)
909 {
910 	struct uio auio;
911 	struct iovec *iov;
912 	struct mbuf *control, *m;
913 	caddr_t ctlbuf;
914 	struct file *fp;
915 	struct socket *so;
916 	struct sockaddr *fromsa = NULL;
917 #ifdef KTRACE
918 	struct uio *ktruio = NULL;
919 #endif
920 	ssize_t len;
921 	int error, i;
922 
923 	if (controlp != NULL)
924 		*controlp = NULL;
925 
926 	AUDIT_ARG_FD(s);
927 	error = getsock_cap(td, s, &cap_recv_rights,
928 	    &fp, NULL, NULL);
929 	if (error != 0)
930 		return (error);
931 	so = fp->f_data;
932 
933 #ifdef MAC
934 	error = mac_socket_check_receive(td->td_ucred, so);
935 	if (error != 0) {
936 		fdrop(fp, td);
937 		return (error);
938 	}
939 #endif
940 
941 	auio.uio_iov = mp->msg_iov;
942 	auio.uio_iovcnt = mp->msg_iovlen;
943 	auio.uio_segflg = UIO_USERSPACE;
944 	auio.uio_rw = UIO_READ;
945 	auio.uio_td = td;
946 	auio.uio_offset = 0;			/* XXX */
947 	auio.uio_resid = 0;
948 	iov = mp->msg_iov;
949 	for (i = 0; i < mp->msg_iovlen; i++, iov++) {
950 		if ((auio.uio_resid += iov->iov_len) < 0) {
951 			fdrop(fp, td);
952 			return (EINVAL);
953 		}
954 	}
955 #ifdef KTRACE
956 	if (KTRPOINT(td, KTR_GENIO))
957 		ktruio = cloneuio(&auio);
958 #endif
959 	control = NULL;
960 	len = auio.uio_resid;
961 	error = soreceive(so, &fromsa, &auio, NULL,
962 	    (mp->msg_control || controlp) ? &control : NULL,
963 	    &mp->msg_flags);
964 	if (error != 0) {
965 		if (auio.uio_resid != len && (error == ERESTART ||
966 		    error == EINTR || error == EWOULDBLOCK))
967 			error = 0;
968 	}
969 	if (fromsa != NULL)
970 		AUDIT_ARG_SOCKADDR(td, AT_FDCWD, fromsa);
971 #ifdef KTRACE
972 	if (ktruio != NULL) {
973 		ktruio->uio_resid = len - auio.uio_resid;
974 		ktrgenio(s, UIO_READ, ktruio, error);
975 	}
976 #endif
977 	if (error != 0)
978 		goto out;
979 	td->td_retval[0] = len - auio.uio_resid;
980 	if (mp->msg_name) {
981 		len = mp->msg_namelen;
982 		if (len <= 0 || fromsa == NULL)
983 			len = 0;
984 		else {
985 			/* save sa_len before it is destroyed by MSG_COMPAT */
986 			len = MIN(len, fromsa->sa_len);
987 #ifdef COMPAT_OLDSOCK
988 			if ((mp->msg_flags & MSG_COMPAT) != 0 &&
989 			    SV_PROC_FLAG(td->td_proc, SV_AOUT))
990 				((struct osockaddr *)fromsa)->sa_family =
991 				    fromsa->sa_family;
992 #endif
993 			if (fromseg == UIO_USERSPACE) {
994 				error = copyout(fromsa, mp->msg_name,
995 				    (unsigned)len);
996 				if (error != 0)
997 					goto out;
998 			} else
999 				bcopy(fromsa, mp->msg_name, len);
1000 		}
1001 		mp->msg_namelen = len;
1002 	}
1003 	if (mp->msg_control && controlp == NULL) {
1004 #ifdef COMPAT_OLDSOCK
1005 		/*
1006 		 * We assume that old recvmsg calls won't receive access
1007 		 * rights and other control info, esp. as control info
1008 		 * is always optional and those options didn't exist in 4.3.
1009 		 * If we receive rights, trim the cmsghdr; anything else
1010 		 * is tossed.
1011 		 */
1012 		if (control && (mp->msg_flags & MSG_COMPAT) != 0 &&
1013 		    SV_PROC_FLAG(td->td_proc, SV_AOUT)) {
1014 			if (mtod(control, struct cmsghdr *)->cmsg_level !=
1015 			    SOL_SOCKET ||
1016 			    mtod(control, struct cmsghdr *)->cmsg_type !=
1017 			    SCM_RIGHTS) {
1018 				mp->msg_controllen = 0;
1019 				goto out;
1020 			}
1021 			control->m_len -= sizeof (struct cmsghdr);
1022 			control->m_data += sizeof (struct cmsghdr);
1023 		}
1024 #endif
1025 		ctlbuf = mp->msg_control;
1026 		len = mp->msg_controllen;
1027 		mp->msg_controllen = 0;
1028 		for (m = control; m != NULL && len >= m->m_len; m = m->m_next) {
1029 			if ((error = copyout(mtod(m, caddr_t), ctlbuf,
1030 			    m->m_len)) != 0)
1031 				goto out;
1032 
1033 			ctlbuf += m->m_len;
1034 			len -= m->m_len;
1035 			mp->msg_controllen += m->m_len;
1036 		}
1037 		if (m != NULL) {
1038 			mp->msg_flags |= MSG_CTRUNC;
1039 			m_dispose_extcontrolm(m);
1040 		}
1041 	}
1042 out:
1043 	fdrop(fp, td);
1044 #ifdef KTRACE
1045 	if (fromsa && KTRPOINT(td, KTR_STRUCT))
1046 		ktrsockaddr(fromsa);
1047 #endif
1048 	free(fromsa, M_SONAME);
1049 
1050 	if (error == 0 && controlp != NULL)
1051 		*controlp = control;
1052 	else if (control != NULL) {
1053 		if (error != 0)
1054 			m_dispose_extcontrolm(control);
1055 		m_freem(control);
1056 	}
1057 
1058 	return (error);
1059 }
1060 
1061 static int
1062 recvit(struct thread *td, int s, struct msghdr *mp, void *namelenp)
1063 {
1064 	int error;
1065 
1066 	error = kern_recvit(td, s, mp, UIO_USERSPACE, NULL);
1067 	if (error != 0)
1068 		return (error);
1069 	if (namelenp != NULL) {
1070 		error = copyout(&mp->msg_namelen, namelenp, sizeof (socklen_t));
1071 #ifdef COMPAT_OLDSOCK
1072 		if ((mp->msg_flags & MSG_COMPAT) != 0 &&
1073 		    SV_PROC_FLAG(td->td_proc, SV_AOUT))
1074 			error = 0;	/* old recvfrom didn't check */
1075 #endif
1076 	}
1077 	return (error);
1078 }
1079 
1080 int
1081 sys_recvfrom(struct thread *td, struct recvfrom_args *uap)
1082 {
1083 	struct msghdr msg;
1084 	struct iovec aiov;
1085 	int error;
1086 
1087 	if (uap->fromlenaddr) {
1088 		error = copyin(uap->fromlenaddr,
1089 		    &msg.msg_namelen, sizeof (msg.msg_namelen));
1090 		if (error != 0)
1091 			goto done2;
1092 	} else {
1093 		msg.msg_namelen = 0;
1094 	}
1095 	msg.msg_name = uap->from;
1096 	msg.msg_iov = &aiov;
1097 	msg.msg_iovlen = 1;
1098 	aiov.iov_base = uap->buf;
1099 	aiov.iov_len = uap->len;
1100 	msg.msg_control = 0;
1101 	msg.msg_flags = uap->flags;
1102 	error = recvit(td, uap->s, &msg, uap->fromlenaddr);
1103 done2:
1104 	return (error);
1105 }
1106 
1107 #ifdef COMPAT_OLDSOCK
1108 int
1109 orecvfrom(struct thread *td, struct recvfrom_args *uap)
1110 {
1111 
1112 	uap->flags |= MSG_COMPAT;
1113 	return (sys_recvfrom(td, uap));
1114 }
1115 #endif
1116 
1117 #ifdef COMPAT_OLDSOCK
1118 int
1119 orecv(struct thread *td, struct orecv_args *uap)
1120 {
1121 	struct msghdr msg;
1122 	struct iovec aiov;
1123 
1124 	msg.msg_name = 0;
1125 	msg.msg_namelen = 0;
1126 	msg.msg_iov = &aiov;
1127 	msg.msg_iovlen = 1;
1128 	aiov.iov_base = uap->buf;
1129 	aiov.iov_len = uap->len;
1130 	msg.msg_control = 0;
1131 	msg.msg_flags = uap->flags;
1132 	return (recvit(td, uap->s, &msg, NULL));
1133 }
1134 
1135 /*
1136  * Old recvmsg.  This code takes advantage of the fact that the old msghdr
1137  * overlays the new one, missing only the flags, and with the (old) access
1138  * rights where the control fields are now.
1139  */
1140 int
1141 orecvmsg(struct thread *td, struct orecvmsg_args *uap)
1142 {
1143 	struct msghdr msg;
1144 	struct iovec *iov;
1145 	int error;
1146 
1147 	error = copyin(uap->msg, &msg, sizeof (struct omsghdr));
1148 	if (error != 0)
1149 		return (error);
1150 	error = copyiniov(msg.msg_iov, msg.msg_iovlen, &iov, EMSGSIZE);
1151 	if (error != 0)
1152 		return (error);
1153 	msg.msg_flags = uap->flags | MSG_COMPAT;
1154 	msg.msg_iov = iov;
1155 	error = recvit(td, uap->s, &msg, &uap->msg->msg_namelen);
1156 	if (msg.msg_controllen && error == 0)
1157 		error = copyout(&msg.msg_controllen,
1158 		    &uap->msg->msg_accrightslen, sizeof (int));
1159 	free(iov, M_IOV);
1160 	return (error);
1161 }
1162 #endif
1163 
1164 int
1165 sys_recvmsg(struct thread *td, struct recvmsg_args *uap)
1166 {
1167 	struct msghdr msg;
1168 	struct iovec *uiov, *iov;
1169 	int error;
1170 
1171 	error = copyin(uap->msg, &msg, sizeof (msg));
1172 	if (error != 0)
1173 		return (error);
1174 	error = copyiniov(msg.msg_iov, msg.msg_iovlen, &iov, EMSGSIZE);
1175 	if (error != 0)
1176 		return (error);
1177 	msg.msg_flags = uap->flags;
1178 #ifdef COMPAT_OLDSOCK
1179 	if (SV_PROC_FLAG(td->td_proc, SV_AOUT))
1180 		msg.msg_flags &= ~MSG_COMPAT;
1181 #endif
1182 	uiov = msg.msg_iov;
1183 	msg.msg_iov = iov;
1184 	error = recvit(td, uap->s, &msg, NULL);
1185 	if (error == 0) {
1186 		msg.msg_iov = uiov;
1187 		error = copyout(&msg, uap->msg, sizeof(msg));
1188 	}
1189 	free(iov, M_IOV);
1190 	return (error);
1191 }
1192 
1193 int
1194 sys_shutdown(struct thread *td, struct shutdown_args *uap)
1195 {
1196 
1197 	return (kern_shutdown(td, uap->s, uap->how));
1198 }
1199 
1200 int
1201 kern_shutdown(struct thread *td, int s, int how)
1202 {
1203 	struct socket *so;
1204 	struct file *fp;
1205 	int error;
1206 
1207 	AUDIT_ARG_FD(s);
1208 	error = getsock_cap(td, s, &cap_shutdown_rights,
1209 	    &fp, NULL, NULL);
1210 	if (error == 0) {
1211 		so = fp->f_data;
1212 		error = soshutdown(so, how);
1213 		/*
1214 		 * Previous versions did not return ENOTCONN, but 0 in
1215 		 * case the socket was not connected. Some important
1216 		 * programs like syslogd up to r279016, 2015-02-19,
1217 		 * still depend on this behavior.
1218 		 */
1219 		if (error == ENOTCONN &&
1220 		    td->td_proc->p_osrel < P_OSREL_SHUTDOWN_ENOTCONN)
1221 			error = 0;
1222 		fdrop(fp, td);
1223 	}
1224 	return (error);
1225 }
1226 
1227 int
1228 sys_setsockopt(struct thread *td, struct setsockopt_args *uap)
1229 {
1230 
1231 	return (kern_setsockopt(td, uap->s, uap->level, uap->name,
1232 	    uap->val, UIO_USERSPACE, uap->valsize));
1233 }
1234 
1235 int
1236 kern_setsockopt(struct thread *td, int s, int level, int name, const void *val,
1237     enum uio_seg valseg, socklen_t valsize)
1238 {
1239 	struct socket *so;
1240 	struct file *fp;
1241 	struct sockopt sopt;
1242 	int error;
1243 
1244 	if (val == NULL && valsize != 0)
1245 		return (EFAULT);
1246 	if ((int)valsize < 0)
1247 		return (EINVAL);
1248 
1249 	sopt.sopt_dir = SOPT_SET;
1250 	sopt.sopt_level = level;
1251 	sopt.sopt_name = name;
1252 	sopt.sopt_val = __DECONST(void *, val);
1253 	sopt.sopt_valsize = valsize;
1254 	switch (valseg) {
1255 	case UIO_USERSPACE:
1256 		sopt.sopt_td = td;
1257 		break;
1258 	case UIO_SYSSPACE:
1259 		sopt.sopt_td = NULL;
1260 		break;
1261 	default:
1262 		panic("kern_setsockopt called with bad valseg");
1263 	}
1264 
1265 	AUDIT_ARG_FD(s);
1266 	error = getsock_cap(td, s, &cap_setsockopt_rights,
1267 	    &fp, NULL, NULL);
1268 	if (error == 0) {
1269 		so = fp->f_data;
1270 		error = sosetopt(so, &sopt);
1271 		fdrop(fp, td);
1272 	}
1273 	return(error);
1274 }
1275 
1276 int
1277 sys_getsockopt(struct thread *td, struct getsockopt_args *uap)
1278 {
1279 	socklen_t valsize;
1280 	int error;
1281 
1282 	if (uap->val) {
1283 		error = copyin(uap->avalsize, &valsize, sizeof (valsize));
1284 		if (error != 0)
1285 			return (error);
1286 	}
1287 
1288 	error = kern_getsockopt(td, uap->s, uap->level, uap->name,
1289 	    uap->val, UIO_USERSPACE, &valsize);
1290 
1291 	if (error == 0)
1292 		error = copyout(&valsize, uap->avalsize, sizeof (valsize));
1293 	return (error);
1294 }
1295 
1296 /*
1297  * Kernel version of getsockopt.
1298  * optval can be a userland or userspace. optlen is always a kernel pointer.
1299  */
1300 int
1301 kern_getsockopt(struct thread *td, int s, int level, int name, void *val,
1302     enum uio_seg valseg, socklen_t *valsize)
1303 {
1304 	struct socket *so;
1305 	struct file *fp;
1306 	struct sockopt sopt;
1307 	int error;
1308 
1309 	if (val == NULL)
1310 		*valsize = 0;
1311 	if ((int)*valsize < 0)
1312 		return (EINVAL);
1313 
1314 	sopt.sopt_dir = SOPT_GET;
1315 	sopt.sopt_level = level;
1316 	sopt.sopt_name = name;
1317 	sopt.sopt_val = val;
1318 	sopt.sopt_valsize = (size_t)*valsize; /* checked non-negative above */
1319 	switch (valseg) {
1320 	case UIO_USERSPACE:
1321 		sopt.sopt_td = td;
1322 		break;
1323 	case UIO_SYSSPACE:
1324 		sopt.sopt_td = NULL;
1325 		break;
1326 	default:
1327 		panic("kern_getsockopt called with bad valseg");
1328 	}
1329 
1330 	AUDIT_ARG_FD(s);
1331 	error = getsock_cap(td, s, &cap_getsockopt_rights,
1332 	    &fp, NULL, NULL);
1333 	if (error == 0) {
1334 		so = fp->f_data;
1335 		error = sogetopt(so, &sopt);
1336 		*valsize = sopt.sopt_valsize;
1337 		fdrop(fp, td);
1338 	}
1339 	return (error);
1340 }
1341 
1342 /*
1343  * getsockname1() - Get socket name.
1344  */
1345 static int
1346 getsockname1(struct thread *td, struct getsockname_args *uap, int compat)
1347 {
1348 	struct sockaddr *sa;
1349 	socklen_t len;
1350 	int error;
1351 
1352 	error = copyin(uap->alen, &len, sizeof(len));
1353 	if (error != 0)
1354 		return (error);
1355 
1356 	error = kern_getsockname(td, uap->fdes, &sa, &len);
1357 	if (error != 0)
1358 		return (error);
1359 
1360 	if (len != 0) {
1361 #ifdef COMPAT_OLDSOCK
1362 		if (compat && SV_PROC_FLAG(td->td_proc, SV_AOUT))
1363 			((struct osockaddr *)sa)->sa_family = sa->sa_family;
1364 #endif
1365 		error = copyout(sa, uap->asa, (u_int)len);
1366 	}
1367 	free(sa, M_SONAME);
1368 	if (error == 0)
1369 		error = copyout(&len, uap->alen, sizeof(len));
1370 	return (error);
1371 }
1372 
1373 int
1374 kern_getsockname(struct thread *td, int fd, struct sockaddr **sa,
1375     socklen_t *alen)
1376 {
1377 	struct socket *so;
1378 	struct file *fp;
1379 	socklen_t len;
1380 	int error;
1381 
1382 	AUDIT_ARG_FD(fd);
1383 	error = getsock_cap(td, fd, &cap_getsockname_rights,
1384 	    &fp, NULL, NULL);
1385 	if (error != 0)
1386 		return (error);
1387 	so = fp->f_data;
1388 	*sa = NULL;
1389 	CURVNET_SET(so->so_vnet);
1390 	error = (*so->so_proto->pr_usrreqs->pru_sockaddr)(so, sa);
1391 	CURVNET_RESTORE();
1392 	if (error != 0)
1393 		goto bad;
1394 	if (*sa == NULL)
1395 		len = 0;
1396 	else
1397 		len = MIN(*alen, (*sa)->sa_len);
1398 	*alen = len;
1399 #ifdef KTRACE
1400 	if (KTRPOINT(td, KTR_STRUCT))
1401 		ktrsockaddr(*sa);
1402 #endif
1403 bad:
1404 	fdrop(fp, td);
1405 	if (error != 0 && *sa != NULL) {
1406 		free(*sa, M_SONAME);
1407 		*sa = NULL;
1408 	}
1409 	return (error);
1410 }
1411 
1412 int
1413 sys_getsockname(struct thread *td, struct getsockname_args *uap)
1414 {
1415 
1416 	return (getsockname1(td, uap, 0));
1417 }
1418 
1419 #ifdef COMPAT_OLDSOCK
1420 int
1421 ogetsockname(struct thread *td, struct getsockname_args *uap)
1422 {
1423 
1424 	return (getsockname1(td, uap, 1));
1425 }
1426 #endif /* COMPAT_OLDSOCK */
1427 
1428 /*
1429  * getpeername1() - Get name of peer for connected socket.
1430  */
1431 static int
1432 getpeername1(struct thread *td, struct getpeername_args *uap, int compat)
1433 {
1434 	struct sockaddr *sa;
1435 	socklen_t len;
1436 	int error;
1437 
1438 	error = copyin(uap->alen, &len, sizeof (len));
1439 	if (error != 0)
1440 		return (error);
1441 
1442 	error = kern_getpeername(td, uap->fdes, &sa, &len);
1443 	if (error != 0)
1444 		return (error);
1445 
1446 	if (len != 0) {
1447 #ifdef COMPAT_OLDSOCK
1448 		if (compat && SV_PROC_FLAG(td->td_proc, SV_AOUT))
1449 			((struct osockaddr *)sa)->sa_family = sa->sa_family;
1450 #endif
1451 		error = copyout(sa, uap->asa, (u_int)len);
1452 	}
1453 	free(sa, M_SONAME);
1454 	if (error == 0)
1455 		error = copyout(&len, uap->alen, sizeof(len));
1456 	return (error);
1457 }
1458 
1459 int
1460 kern_getpeername(struct thread *td, int fd, struct sockaddr **sa,
1461     socklen_t *alen)
1462 {
1463 	struct socket *so;
1464 	struct file *fp;
1465 	socklen_t len;
1466 	int error;
1467 
1468 	AUDIT_ARG_FD(fd);
1469 	error = getsock_cap(td, fd, &cap_getpeername_rights,
1470 	    &fp, NULL, NULL);
1471 	if (error != 0)
1472 		return (error);
1473 	so = fp->f_data;
1474 	if ((so->so_state & (SS_ISCONNECTED|SS_ISCONFIRMING)) == 0) {
1475 		error = ENOTCONN;
1476 		goto done;
1477 	}
1478 	*sa = NULL;
1479 	CURVNET_SET(so->so_vnet);
1480 	error = (*so->so_proto->pr_usrreqs->pru_peeraddr)(so, sa);
1481 	CURVNET_RESTORE();
1482 	if (error != 0)
1483 		goto bad;
1484 	if (*sa == NULL)
1485 		len = 0;
1486 	else
1487 		len = MIN(*alen, (*sa)->sa_len);
1488 	*alen = len;
1489 #ifdef KTRACE
1490 	if (KTRPOINT(td, KTR_STRUCT))
1491 		ktrsockaddr(*sa);
1492 #endif
1493 bad:
1494 	if (error != 0 && *sa != NULL) {
1495 		free(*sa, M_SONAME);
1496 		*sa = NULL;
1497 	}
1498 done:
1499 	fdrop(fp, td);
1500 	return (error);
1501 }
1502 
1503 int
1504 sys_getpeername(struct thread *td, struct getpeername_args *uap)
1505 {
1506 
1507 	return (getpeername1(td, uap, 0));
1508 }
1509 
1510 #ifdef COMPAT_OLDSOCK
1511 int
1512 ogetpeername(struct thread *td, struct ogetpeername_args *uap)
1513 {
1514 
1515 	/* XXX uap should have type `getpeername_args *' to begin with. */
1516 	return (getpeername1(td, (struct getpeername_args *)uap, 1));
1517 }
1518 #endif /* COMPAT_OLDSOCK */
1519 
1520 static int
1521 sockargs(struct mbuf **mp, char *buf, socklen_t buflen, int type)
1522 {
1523 	struct sockaddr *sa;
1524 	struct mbuf *m;
1525 	int error;
1526 
1527 	if (buflen > MLEN) {
1528 #ifdef COMPAT_OLDSOCK
1529 		if (type == MT_SONAME && buflen <= 112 &&
1530 		    SV_CURPROC_FLAG(SV_AOUT))
1531 			buflen = MLEN;		/* unix domain compat. hack */
1532 		else
1533 #endif
1534 			if (buflen > MCLBYTES)
1535 				return (EINVAL);
1536 	}
1537 	m = m_get2(buflen, M_WAITOK, type, 0);
1538 	m->m_len = buflen;
1539 	error = copyin(buf, mtod(m, void *), buflen);
1540 	if (error != 0)
1541 		(void) m_free(m);
1542 	else {
1543 		*mp = m;
1544 		if (type == MT_SONAME) {
1545 			sa = mtod(m, struct sockaddr *);
1546 
1547 #if defined(COMPAT_OLDSOCK) && BYTE_ORDER != BIG_ENDIAN
1548 			if (sa->sa_family == 0 && sa->sa_len < AF_MAX &&
1549 			    SV_CURPROC_FLAG(SV_AOUT))
1550 				sa->sa_family = sa->sa_len;
1551 #endif
1552 			sa->sa_len = buflen;
1553 		}
1554 	}
1555 	return (error);
1556 }
1557 
1558 int
1559 getsockaddr(struct sockaddr **namp, const struct sockaddr *uaddr, size_t len)
1560 {
1561 	struct sockaddr *sa;
1562 	int error;
1563 
1564 	if (len > SOCK_MAXADDRLEN)
1565 		return (ENAMETOOLONG);
1566 	if (len < offsetof(struct sockaddr, sa_data[0]))
1567 		return (EINVAL);
1568 	sa = malloc(len, M_SONAME, M_WAITOK);
1569 	error = copyin(uaddr, sa, len);
1570 	if (error != 0) {
1571 		free(sa, M_SONAME);
1572 	} else {
1573 #if defined(COMPAT_OLDSOCK) && BYTE_ORDER != BIG_ENDIAN
1574 		if (sa->sa_family == 0 && sa->sa_len < AF_MAX &&
1575 		    SV_CURPROC_FLAG(SV_AOUT))
1576 			sa->sa_family = sa->sa_len;
1577 #endif
1578 		sa->sa_len = len;
1579 		*namp = sa;
1580 	}
1581 	return (error);
1582 }
1583 
1584 /*
1585  * Dispose of externalized rights from an SCM_RIGHTS message.  This function
1586  * should be used in error or truncation cases to avoid leaking file descriptors
1587  * into the recipient's (the current thread's) table.
1588  */
1589 void
1590 m_dispose_extcontrolm(struct mbuf *m)
1591 {
1592 	struct cmsghdr *cm;
1593 	struct file *fp;
1594 	struct thread *td;
1595 	socklen_t clen, datalen;
1596 	int error, fd, *fds, nfd;
1597 
1598 	td = curthread;
1599 	for (; m != NULL; m = m->m_next) {
1600 		if (m->m_type != MT_EXTCONTROL)
1601 			continue;
1602 		cm = mtod(m, struct cmsghdr *);
1603 		clen = m->m_len;
1604 		while (clen > 0) {
1605 			if (clen < sizeof(*cm))
1606 				panic("%s: truncated mbuf %p", __func__, m);
1607 			datalen = CMSG_SPACE(cm->cmsg_len - CMSG_SPACE(0));
1608 			if (clen < datalen)
1609 				panic("%s: truncated mbuf %p", __func__, m);
1610 
1611 			if (cm->cmsg_level == SOL_SOCKET &&
1612 			    cm->cmsg_type == SCM_RIGHTS) {
1613 				fds = (int *)CMSG_DATA(cm);
1614 				nfd = (cm->cmsg_len - CMSG_SPACE(0)) /
1615 				    sizeof(int);
1616 
1617 				while (nfd-- > 0) {
1618 					fd = *fds++;
1619 					error = fget(td, fd, &cap_no_rights,
1620 					    &fp);
1621 					if (error == 0) {
1622 						fdclose(td, fp, fd);
1623 						fdrop(fp, td);
1624 					}
1625 				}
1626 			}
1627 			clen -= datalen;
1628 			cm = (struct cmsghdr *)((uint8_t *)cm + datalen);
1629 		}
1630 		m_chtype(m, MT_CONTROL);
1631 	}
1632 }
1633