xref: /freebsd/sys/kern/vfs_syscalls.c (revision 2f02600abfddfc4e9f20dd384a2e729b451e16bd)
1 /*-
2  * Copyright (c) 1989, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  * (c) UNIX System Laboratories, Inc.
5  * All or some portions of this file are derived from material licensed
6  * to the University of California by American Telephone and Telegraph
7  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
8  * the permission of UNIX System Laboratories, Inc.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 4. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  *	@(#)vfs_syscalls.c	8.13 (Berkeley) 4/15/94
35  */
36 
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
39 
40 #include "opt_capsicum.h"
41 #include "opt_compat.h"
42 #include "opt_ktrace.h"
43 
44 #include <sys/param.h>
45 #include <sys/systm.h>
46 #include <sys/bio.h>
47 #include <sys/buf.h>
48 #include <sys/capability.h>
49 #include <sys/disk.h>
50 #include <sys/sysent.h>
51 #include <sys/malloc.h>
52 #include <sys/mount.h>
53 #include <sys/mutex.h>
54 #include <sys/sysproto.h>
55 #include <sys/namei.h>
56 #include <sys/filedesc.h>
57 #include <sys/kernel.h>
58 #include <sys/fcntl.h>
59 #include <sys/file.h>
60 #include <sys/filio.h>
61 #include <sys/limits.h>
62 #include <sys/linker.h>
63 #include <sys/rwlock.h>
64 #include <sys/sdt.h>
65 #include <sys/stat.h>
66 #include <sys/sx.h>
67 #include <sys/unistd.h>
68 #include <sys/vnode.h>
69 #include <sys/priv.h>
70 #include <sys/proc.h>
71 #include <sys/dirent.h>
72 #include <sys/jail.h>
73 #include <sys/syscallsubr.h>
74 #include <sys/sysctl.h>
75 #ifdef KTRACE
76 #include <sys/ktrace.h>
77 #endif
78 
79 #include <machine/stdarg.h>
80 
81 #include <security/audit/audit.h>
82 #include <security/mac/mac_framework.h>
83 
84 #include <vm/vm.h>
85 #include <vm/vm_object.h>
86 #include <vm/vm_page.h>
87 #include <vm/uma.h>
88 
89 #include <ufs/ufs/quota.h>
90 
91 MALLOC_DEFINE(M_FADVISE, "fadvise", "posix_fadvise(2) information");
92 
93 SDT_PROVIDER_DEFINE(vfs);
94 SDT_PROBE_DEFINE2(vfs, , stat, mode, "char *", "int");
95 SDT_PROBE_DEFINE2(vfs, , stat, reg, "char *", "int");
96 
97 static int chroot_refuse_vdir_fds(struct filedesc *fdp);
98 static int getutimes(const struct timeval *, enum uio_seg, struct timespec *);
99 static int kern_chflags(struct thread *td, const char *path,
100     enum uio_seg pathseg, u_long flags);
101 static int kern_chflagsat(struct thread *td, int fd, const char *path,
102     enum uio_seg pathseg, u_long flags, int atflag);
103 static int setfflags(struct thread *td, struct vnode *, u_long);
104 static int setutimes(struct thread *td, struct vnode *,
105     const struct timespec *, int, int);
106 static int vn_access(struct vnode *vp, int user_flags, struct ucred *cred,
107     struct thread *td);
108 
109 /*
110  * The module initialization routine for POSIX asynchronous I/O will
111  * set this to the version of AIO that it implements.  (Zero means
112  * that it is not implemented.)  This value is used here by pathconf()
113  * and in kern_descrip.c by fpathconf().
114  */
115 int async_io_version;
116 
117 #ifdef DEBUG
118 static int syncprt = 0;
119 SYSCTL_INT(_debug, OID_AUTO, syncprt, CTLFLAG_RW, &syncprt, 0, "");
120 #endif
121 
122 /*
123  * Sync each mounted filesystem.
124  */
125 #ifndef _SYS_SYSPROTO_H_
126 struct sync_args {
127 	int     dummy;
128 };
129 #endif
130 /* ARGSUSED */
131 int
132 sys_sync(td, uap)
133 	struct thread *td;
134 	struct sync_args *uap;
135 {
136 	struct mount *mp, *nmp;
137 	int save;
138 
139 	mtx_lock(&mountlist_mtx);
140 	for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) {
141 		if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK)) {
142 			nmp = TAILQ_NEXT(mp, mnt_list);
143 			continue;
144 		}
145 		if ((mp->mnt_flag & MNT_RDONLY) == 0 &&
146 		    vn_start_write(NULL, &mp, V_NOWAIT) == 0) {
147 			save = curthread_pflags_set(TDP_SYNCIO);
148 			vfs_msync(mp, MNT_NOWAIT);
149 			VFS_SYNC(mp, MNT_NOWAIT);
150 			curthread_pflags_restore(save);
151 			vn_finished_write(mp);
152 		}
153 		mtx_lock(&mountlist_mtx);
154 		nmp = TAILQ_NEXT(mp, mnt_list);
155 		vfs_unbusy(mp);
156 	}
157 	mtx_unlock(&mountlist_mtx);
158 	return (0);
159 }
160 
161 /*
162  * Change filesystem quotas.
163  */
164 #ifndef _SYS_SYSPROTO_H_
165 struct quotactl_args {
166 	char *path;
167 	int cmd;
168 	int uid;
169 	caddr_t arg;
170 };
171 #endif
172 int
173 sys_quotactl(td, uap)
174 	struct thread *td;
175 	register struct quotactl_args /* {
176 		char *path;
177 		int cmd;
178 		int uid;
179 		caddr_t arg;
180 	} */ *uap;
181 {
182 	struct mount *mp;
183 	struct nameidata nd;
184 	int error;
185 
186 	AUDIT_ARG_CMD(uap->cmd);
187 	AUDIT_ARG_UID(uap->uid);
188 	if (!prison_allow(td->td_ucred, PR_ALLOW_QUOTAS))
189 		return (EPERM);
190 	NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | AUDITVNODE1, UIO_USERSPACE,
191 	    uap->path, td);
192 	if ((error = namei(&nd)) != 0)
193 		return (error);
194 	NDFREE(&nd, NDF_ONLY_PNBUF);
195 	mp = nd.ni_vp->v_mount;
196 	vfs_ref(mp);
197 	vput(nd.ni_vp);
198 	error = vfs_busy(mp, 0);
199 	vfs_rel(mp);
200 	if (error != 0)
201 		return (error);
202 	error = VFS_QUOTACTL(mp, uap->cmd, uap->uid, uap->arg);
203 
204 	/*
205 	 * Since quota on operation typically needs to open quota
206 	 * file, the Q_QUOTAON handler needs to unbusy the mount point
207 	 * before calling into namei.  Otherwise, unmount might be
208 	 * started between two vfs_busy() invocations (first is our,
209 	 * second is from mount point cross-walk code in lookup()),
210 	 * causing deadlock.
211 	 *
212 	 * Require that Q_QUOTAON handles the vfs_busy() reference on
213 	 * its own, always returning with ubusied mount point.
214 	 */
215 	if ((uap->cmd >> SUBCMDSHIFT) != Q_QUOTAON)
216 		vfs_unbusy(mp);
217 	return (error);
218 }
219 
220 /*
221  * Used by statfs conversion routines to scale the block size up if
222  * necessary so that all of the block counts are <= 'max_size'.  Note
223  * that 'max_size' should be a bitmask, i.e. 2^n - 1 for some non-zero
224  * value of 'n'.
225  */
226 void
227 statfs_scale_blocks(struct statfs *sf, long max_size)
228 {
229 	uint64_t count;
230 	int shift;
231 
232 	KASSERT(powerof2(max_size + 1), ("%s: invalid max_size", __func__));
233 
234 	/*
235 	 * Attempt to scale the block counts to give a more accurate
236 	 * overview to userland of the ratio of free space to used
237 	 * space.  To do this, find the largest block count and compute
238 	 * a divisor that lets it fit into a signed integer <= max_size.
239 	 */
240 	if (sf->f_bavail < 0)
241 		count = -sf->f_bavail;
242 	else
243 		count = sf->f_bavail;
244 	count = MAX(sf->f_blocks, MAX(sf->f_bfree, count));
245 	if (count <= max_size)
246 		return;
247 
248 	count >>= flsl(max_size);
249 	shift = 0;
250 	while (count > 0) {
251 		shift++;
252 		count >>=1;
253 	}
254 
255 	sf->f_bsize <<= shift;
256 	sf->f_blocks >>= shift;
257 	sf->f_bfree >>= shift;
258 	sf->f_bavail >>= shift;
259 }
260 
261 /*
262  * Get filesystem statistics.
263  */
264 #ifndef _SYS_SYSPROTO_H_
265 struct statfs_args {
266 	char *path;
267 	struct statfs *buf;
268 };
269 #endif
270 int
271 sys_statfs(td, uap)
272 	struct thread *td;
273 	register struct statfs_args /* {
274 		char *path;
275 		struct statfs *buf;
276 	} */ *uap;
277 {
278 	struct statfs sf;
279 	int error;
280 
281 	error = kern_statfs(td, uap->path, UIO_USERSPACE, &sf);
282 	if (error == 0)
283 		error = copyout(&sf, uap->buf, sizeof(sf));
284 	return (error);
285 }
286 
287 int
288 kern_statfs(struct thread *td, char *path, enum uio_seg pathseg,
289     struct statfs *buf)
290 {
291 	struct mount *mp;
292 	struct statfs *sp, sb;
293 	struct nameidata nd;
294 	int error;
295 
296 	NDINIT(&nd, LOOKUP, FOLLOW | LOCKSHARED | LOCKLEAF | AUDITVNODE1,
297 	    pathseg, path, td);
298 	error = namei(&nd);
299 	if (error != 0)
300 		return (error);
301 	mp = nd.ni_vp->v_mount;
302 	vfs_ref(mp);
303 	NDFREE(&nd, NDF_ONLY_PNBUF);
304 	vput(nd.ni_vp);
305 	error = vfs_busy(mp, 0);
306 	vfs_rel(mp);
307 	if (error != 0)
308 		return (error);
309 #ifdef MAC
310 	error = mac_mount_check_stat(td->td_ucred, mp);
311 	if (error != 0)
312 		goto out;
313 #endif
314 	/*
315 	 * Set these in case the underlying filesystem fails to do so.
316 	 */
317 	sp = &mp->mnt_stat;
318 	sp->f_version = STATFS_VERSION;
319 	sp->f_namemax = NAME_MAX;
320 	sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
321 	error = VFS_STATFS(mp, sp);
322 	if (error != 0)
323 		goto out;
324 	if (priv_check(td, PRIV_VFS_GENERATION)) {
325 		bcopy(sp, &sb, sizeof(sb));
326 		sb.f_fsid.val[0] = sb.f_fsid.val[1] = 0;
327 		prison_enforce_statfs(td->td_ucred, mp, &sb);
328 		sp = &sb;
329 	}
330 	*buf = *sp;
331 out:
332 	vfs_unbusy(mp);
333 	return (error);
334 }
335 
336 /*
337  * Get filesystem statistics.
338  */
339 #ifndef _SYS_SYSPROTO_H_
340 struct fstatfs_args {
341 	int fd;
342 	struct statfs *buf;
343 };
344 #endif
345 int
346 sys_fstatfs(td, uap)
347 	struct thread *td;
348 	register struct fstatfs_args /* {
349 		int fd;
350 		struct statfs *buf;
351 	} */ *uap;
352 {
353 	struct statfs sf;
354 	int error;
355 
356 	error = kern_fstatfs(td, uap->fd, &sf);
357 	if (error == 0)
358 		error = copyout(&sf, uap->buf, sizeof(sf));
359 	return (error);
360 }
361 
362 int
363 kern_fstatfs(struct thread *td, int fd, struct statfs *buf)
364 {
365 	struct file *fp;
366 	struct mount *mp;
367 	struct statfs *sp, sb;
368 	struct vnode *vp;
369 	cap_rights_t rights;
370 	int error;
371 
372 	AUDIT_ARG_FD(fd);
373 	error = getvnode(td->td_proc->p_fd, fd,
374 	    cap_rights_init(&rights, CAP_FSTATFS), &fp);
375 	if (error != 0)
376 		return (error);
377 	vp = fp->f_vnode;
378 	vn_lock(vp, LK_SHARED | LK_RETRY);
379 #ifdef AUDIT
380 	AUDIT_ARG_VNODE1(vp);
381 #endif
382 	mp = vp->v_mount;
383 	if (mp)
384 		vfs_ref(mp);
385 	VOP_UNLOCK(vp, 0);
386 	fdrop(fp, td);
387 	if (mp == NULL) {
388 		error = EBADF;
389 		goto out;
390 	}
391 	error = vfs_busy(mp, 0);
392 	vfs_rel(mp);
393 	if (error != 0)
394 		return (error);
395 #ifdef MAC
396 	error = mac_mount_check_stat(td->td_ucred, mp);
397 	if (error != 0)
398 		goto out;
399 #endif
400 	/*
401 	 * Set these in case the underlying filesystem fails to do so.
402 	 */
403 	sp = &mp->mnt_stat;
404 	sp->f_version = STATFS_VERSION;
405 	sp->f_namemax = NAME_MAX;
406 	sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
407 	error = VFS_STATFS(mp, sp);
408 	if (error != 0)
409 		goto out;
410 	if (priv_check(td, PRIV_VFS_GENERATION)) {
411 		bcopy(sp, &sb, sizeof(sb));
412 		sb.f_fsid.val[0] = sb.f_fsid.val[1] = 0;
413 		prison_enforce_statfs(td->td_ucred, mp, &sb);
414 		sp = &sb;
415 	}
416 	*buf = *sp;
417 out:
418 	if (mp)
419 		vfs_unbusy(mp);
420 	return (error);
421 }
422 
423 /*
424  * Get statistics on all filesystems.
425  */
426 #ifndef _SYS_SYSPROTO_H_
427 struct getfsstat_args {
428 	struct statfs *buf;
429 	long bufsize;
430 	int flags;
431 };
432 #endif
433 int
434 sys_getfsstat(td, uap)
435 	struct thread *td;
436 	register struct getfsstat_args /* {
437 		struct statfs *buf;
438 		long bufsize;
439 		int flags;
440 	} */ *uap;
441 {
442 
443 	return (kern_getfsstat(td, &uap->buf, uap->bufsize, UIO_USERSPACE,
444 	    uap->flags));
445 }
446 
447 /*
448  * If (bufsize > 0 && bufseg == UIO_SYSSPACE)
449  *	The caller is responsible for freeing memory which will be allocated
450  *	in '*buf'.
451  */
452 int
453 kern_getfsstat(struct thread *td, struct statfs **buf, size_t bufsize,
454     enum uio_seg bufseg, int flags)
455 {
456 	struct mount *mp, *nmp;
457 	struct statfs *sfsp, *sp, sb;
458 	size_t count, maxcount;
459 	int error;
460 
461 	maxcount = bufsize / sizeof(struct statfs);
462 	if (bufsize == 0)
463 		sfsp = NULL;
464 	else if (bufseg == UIO_USERSPACE)
465 		sfsp = *buf;
466 	else /* if (bufseg == UIO_SYSSPACE) */ {
467 		count = 0;
468 		mtx_lock(&mountlist_mtx);
469 		TAILQ_FOREACH(mp, &mountlist, mnt_list) {
470 			count++;
471 		}
472 		mtx_unlock(&mountlist_mtx);
473 		if (maxcount > count)
474 			maxcount = count;
475 		sfsp = *buf = malloc(maxcount * sizeof(struct statfs), M_TEMP,
476 		    M_WAITOK);
477 	}
478 	count = 0;
479 	mtx_lock(&mountlist_mtx);
480 	for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) {
481 		if (prison_canseemount(td->td_ucred, mp) != 0) {
482 			nmp = TAILQ_NEXT(mp, mnt_list);
483 			continue;
484 		}
485 #ifdef MAC
486 		if (mac_mount_check_stat(td->td_ucred, mp) != 0) {
487 			nmp = TAILQ_NEXT(mp, mnt_list);
488 			continue;
489 		}
490 #endif
491 		if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK)) {
492 			nmp = TAILQ_NEXT(mp, mnt_list);
493 			continue;
494 		}
495 		if (sfsp && count < maxcount) {
496 			sp = &mp->mnt_stat;
497 			/*
498 			 * Set these in case the underlying filesystem
499 			 * fails to do so.
500 			 */
501 			sp->f_version = STATFS_VERSION;
502 			sp->f_namemax = NAME_MAX;
503 			sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
504 			/*
505 			 * If MNT_NOWAIT or MNT_LAZY is specified, do not
506 			 * refresh the fsstat cache. MNT_NOWAIT or MNT_LAZY
507 			 * overrides MNT_WAIT.
508 			 */
509 			if (((flags & (MNT_LAZY|MNT_NOWAIT)) == 0 ||
510 			    (flags & MNT_WAIT)) &&
511 			    (error = VFS_STATFS(mp, sp))) {
512 				mtx_lock(&mountlist_mtx);
513 				nmp = TAILQ_NEXT(mp, mnt_list);
514 				vfs_unbusy(mp);
515 				continue;
516 			}
517 			if (priv_check(td, PRIV_VFS_GENERATION)) {
518 				bcopy(sp, &sb, sizeof(sb));
519 				sb.f_fsid.val[0] = sb.f_fsid.val[1] = 0;
520 				prison_enforce_statfs(td->td_ucred, mp, &sb);
521 				sp = &sb;
522 			}
523 			if (bufseg == UIO_SYSSPACE)
524 				bcopy(sp, sfsp, sizeof(*sp));
525 			else /* if (bufseg == UIO_USERSPACE) */ {
526 				error = copyout(sp, sfsp, sizeof(*sp));
527 				if (error != 0) {
528 					vfs_unbusy(mp);
529 					return (error);
530 				}
531 			}
532 			sfsp++;
533 		}
534 		count++;
535 		mtx_lock(&mountlist_mtx);
536 		nmp = TAILQ_NEXT(mp, mnt_list);
537 		vfs_unbusy(mp);
538 	}
539 	mtx_unlock(&mountlist_mtx);
540 	if (sfsp && count > maxcount)
541 		td->td_retval[0] = maxcount;
542 	else
543 		td->td_retval[0] = count;
544 	return (0);
545 }
546 
547 #ifdef COMPAT_FREEBSD4
548 /*
549  * Get old format filesystem statistics.
550  */
551 static void cvtstatfs(struct statfs *, struct ostatfs *);
552 
553 #ifndef _SYS_SYSPROTO_H_
554 struct freebsd4_statfs_args {
555 	char *path;
556 	struct ostatfs *buf;
557 };
558 #endif
559 int
560 freebsd4_statfs(td, uap)
561 	struct thread *td;
562 	struct freebsd4_statfs_args /* {
563 		char *path;
564 		struct ostatfs *buf;
565 	} */ *uap;
566 {
567 	struct ostatfs osb;
568 	struct statfs sf;
569 	int error;
570 
571 	error = kern_statfs(td, uap->path, UIO_USERSPACE, &sf);
572 	if (error != 0)
573 		return (error);
574 	cvtstatfs(&sf, &osb);
575 	return (copyout(&osb, uap->buf, sizeof(osb)));
576 }
577 
578 /*
579  * Get filesystem statistics.
580  */
581 #ifndef _SYS_SYSPROTO_H_
582 struct freebsd4_fstatfs_args {
583 	int fd;
584 	struct ostatfs *buf;
585 };
586 #endif
587 int
588 freebsd4_fstatfs(td, uap)
589 	struct thread *td;
590 	struct freebsd4_fstatfs_args /* {
591 		int fd;
592 		struct ostatfs *buf;
593 	} */ *uap;
594 {
595 	struct ostatfs osb;
596 	struct statfs sf;
597 	int error;
598 
599 	error = kern_fstatfs(td, uap->fd, &sf);
600 	if (error != 0)
601 		return (error);
602 	cvtstatfs(&sf, &osb);
603 	return (copyout(&osb, uap->buf, sizeof(osb)));
604 }
605 
606 /*
607  * Get statistics on all filesystems.
608  */
609 #ifndef _SYS_SYSPROTO_H_
610 struct freebsd4_getfsstat_args {
611 	struct ostatfs *buf;
612 	long bufsize;
613 	int flags;
614 };
615 #endif
616 int
617 freebsd4_getfsstat(td, uap)
618 	struct thread *td;
619 	register struct freebsd4_getfsstat_args /* {
620 		struct ostatfs *buf;
621 		long bufsize;
622 		int flags;
623 	} */ *uap;
624 {
625 	struct statfs *buf, *sp;
626 	struct ostatfs osb;
627 	size_t count, size;
628 	int error;
629 
630 	count = uap->bufsize / sizeof(struct ostatfs);
631 	size = count * sizeof(struct statfs);
632 	error = kern_getfsstat(td, &buf, size, UIO_SYSSPACE, uap->flags);
633 	if (size > 0) {
634 		count = td->td_retval[0];
635 		sp = buf;
636 		while (count > 0 && error == 0) {
637 			cvtstatfs(sp, &osb);
638 			error = copyout(&osb, uap->buf, sizeof(osb));
639 			sp++;
640 			uap->buf++;
641 			count--;
642 		}
643 		free(buf, M_TEMP);
644 	}
645 	return (error);
646 }
647 
648 /*
649  * Implement fstatfs() for (NFS) file handles.
650  */
651 #ifndef _SYS_SYSPROTO_H_
652 struct freebsd4_fhstatfs_args {
653 	struct fhandle *u_fhp;
654 	struct ostatfs *buf;
655 };
656 #endif
657 int
658 freebsd4_fhstatfs(td, uap)
659 	struct thread *td;
660 	struct freebsd4_fhstatfs_args /* {
661 		struct fhandle *u_fhp;
662 		struct ostatfs *buf;
663 	} */ *uap;
664 {
665 	struct ostatfs osb;
666 	struct statfs sf;
667 	fhandle_t fh;
668 	int error;
669 
670 	error = copyin(uap->u_fhp, &fh, sizeof(fhandle_t));
671 	if (error != 0)
672 		return (error);
673 	error = kern_fhstatfs(td, fh, &sf);
674 	if (error != 0)
675 		return (error);
676 	cvtstatfs(&sf, &osb);
677 	return (copyout(&osb, uap->buf, sizeof(osb)));
678 }
679 
680 /*
681  * Convert a new format statfs structure to an old format statfs structure.
682  */
683 static void
684 cvtstatfs(nsp, osp)
685 	struct statfs *nsp;
686 	struct ostatfs *osp;
687 {
688 
689 	statfs_scale_blocks(nsp, LONG_MAX);
690 	bzero(osp, sizeof(*osp));
691 	osp->f_bsize = nsp->f_bsize;
692 	osp->f_iosize = MIN(nsp->f_iosize, LONG_MAX);
693 	osp->f_blocks = nsp->f_blocks;
694 	osp->f_bfree = nsp->f_bfree;
695 	osp->f_bavail = nsp->f_bavail;
696 	osp->f_files = MIN(nsp->f_files, LONG_MAX);
697 	osp->f_ffree = MIN(nsp->f_ffree, LONG_MAX);
698 	osp->f_owner = nsp->f_owner;
699 	osp->f_type = nsp->f_type;
700 	osp->f_flags = nsp->f_flags;
701 	osp->f_syncwrites = MIN(nsp->f_syncwrites, LONG_MAX);
702 	osp->f_asyncwrites = MIN(nsp->f_asyncwrites, LONG_MAX);
703 	osp->f_syncreads = MIN(nsp->f_syncreads, LONG_MAX);
704 	osp->f_asyncreads = MIN(nsp->f_asyncreads, LONG_MAX);
705 	strlcpy(osp->f_fstypename, nsp->f_fstypename,
706 	    MIN(MFSNAMELEN, OMFSNAMELEN));
707 	strlcpy(osp->f_mntonname, nsp->f_mntonname,
708 	    MIN(MNAMELEN, OMNAMELEN));
709 	strlcpy(osp->f_mntfromname, nsp->f_mntfromname,
710 	    MIN(MNAMELEN, OMNAMELEN));
711 	osp->f_fsid = nsp->f_fsid;
712 }
713 #endif /* COMPAT_FREEBSD4 */
714 
715 /*
716  * Change current working directory to a given file descriptor.
717  */
718 #ifndef _SYS_SYSPROTO_H_
719 struct fchdir_args {
720 	int	fd;
721 };
722 #endif
723 int
724 sys_fchdir(td, uap)
725 	struct thread *td;
726 	struct fchdir_args /* {
727 		int fd;
728 	} */ *uap;
729 {
730 	register struct filedesc *fdp = td->td_proc->p_fd;
731 	struct vnode *vp, *tdp, *vpold;
732 	struct mount *mp;
733 	struct file *fp;
734 	cap_rights_t rights;
735 	int error;
736 
737 	AUDIT_ARG_FD(uap->fd);
738 	error = getvnode(fdp, uap->fd, cap_rights_init(&rights, CAP_FCHDIR),
739 	    &fp);
740 	if (error != 0)
741 		return (error);
742 	vp = fp->f_vnode;
743 	VREF(vp);
744 	fdrop(fp, td);
745 	vn_lock(vp, LK_SHARED | LK_RETRY);
746 	AUDIT_ARG_VNODE1(vp);
747 	error = change_dir(vp, td);
748 	while (!error && (mp = vp->v_mountedhere) != NULL) {
749 		if (vfs_busy(mp, 0))
750 			continue;
751 		error = VFS_ROOT(mp, LK_SHARED, &tdp);
752 		vfs_unbusy(mp);
753 		if (error != 0)
754 			break;
755 		vput(vp);
756 		vp = tdp;
757 	}
758 	if (error != 0) {
759 		vput(vp);
760 		return (error);
761 	}
762 	VOP_UNLOCK(vp, 0);
763 	FILEDESC_XLOCK(fdp);
764 	vpold = fdp->fd_cdir;
765 	fdp->fd_cdir = vp;
766 	FILEDESC_XUNLOCK(fdp);
767 	vrele(vpold);
768 	return (0);
769 }
770 
771 /*
772  * Change current working directory (``.'').
773  */
774 #ifndef _SYS_SYSPROTO_H_
775 struct chdir_args {
776 	char	*path;
777 };
778 #endif
779 int
780 sys_chdir(td, uap)
781 	struct thread *td;
782 	struct chdir_args /* {
783 		char *path;
784 	} */ *uap;
785 {
786 
787 	return (kern_chdir(td, uap->path, UIO_USERSPACE));
788 }
789 
790 int
791 kern_chdir(struct thread *td, char *path, enum uio_seg pathseg)
792 {
793 	register struct filedesc *fdp = td->td_proc->p_fd;
794 	struct nameidata nd;
795 	struct vnode *vp;
796 	int error;
797 
798 	NDINIT(&nd, LOOKUP, FOLLOW | LOCKSHARED | LOCKLEAF | AUDITVNODE1,
799 	    pathseg, path, td);
800 	if ((error = namei(&nd)) != 0)
801 		return (error);
802 	if ((error = change_dir(nd.ni_vp, td)) != 0) {
803 		vput(nd.ni_vp);
804 		NDFREE(&nd, NDF_ONLY_PNBUF);
805 		return (error);
806 	}
807 	VOP_UNLOCK(nd.ni_vp, 0);
808 	NDFREE(&nd, NDF_ONLY_PNBUF);
809 	FILEDESC_XLOCK(fdp);
810 	vp = fdp->fd_cdir;
811 	fdp->fd_cdir = nd.ni_vp;
812 	FILEDESC_XUNLOCK(fdp);
813 	vrele(vp);
814 	return (0);
815 }
816 
817 /*
818  * Helper function for raised chroot(2) security function:  Refuse if
819  * any filedescriptors are open directories.
820  */
821 static int
822 chroot_refuse_vdir_fds(fdp)
823 	struct filedesc *fdp;
824 {
825 	struct vnode *vp;
826 	struct file *fp;
827 	int fd;
828 
829 	FILEDESC_LOCK_ASSERT(fdp);
830 
831 	for (fd = 0; fd < fdp->fd_nfiles ; fd++) {
832 		fp = fget_locked(fdp, fd);
833 		if (fp == NULL)
834 			continue;
835 		if (fp->f_type == DTYPE_VNODE) {
836 			vp = fp->f_vnode;
837 			if (vp->v_type == VDIR)
838 				return (EPERM);
839 		}
840 	}
841 	return (0);
842 }
843 
844 /*
845  * This sysctl determines if we will allow a process to chroot(2) if it
846  * has a directory open:
847  *	0: disallowed for all processes.
848  *	1: allowed for processes that were not already chroot(2)'ed.
849  *	2: allowed for all processes.
850  */
851 
852 static int chroot_allow_open_directories = 1;
853 
854 SYSCTL_INT(_kern, OID_AUTO, chroot_allow_open_directories, CTLFLAG_RW,
855      &chroot_allow_open_directories, 0,
856      "Allow a process to chroot(2) if it has a directory open");
857 
858 /*
859  * Change notion of root (``/'') directory.
860  */
861 #ifndef _SYS_SYSPROTO_H_
862 struct chroot_args {
863 	char	*path;
864 };
865 #endif
866 int
867 sys_chroot(td, uap)
868 	struct thread *td;
869 	struct chroot_args /* {
870 		char *path;
871 	} */ *uap;
872 {
873 	struct nameidata nd;
874 	int error;
875 
876 	error = priv_check(td, PRIV_VFS_CHROOT);
877 	if (error != 0)
878 		return (error);
879 	NDINIT(&nd, LOOKUP, FOLLOW | LOCKSHARED | LOCKLEAF | AUDITVNODE1,
880 	    UIO_USERSPACE, uap->path, td);
881 	error = namei(&nd);
882 	if (error != 0)
883 		goto error;
884 	error = change_dir(nd.ni_vp, td);
885 	if (error != 0)
886 		goto e_vunlock;
887 #ifdef MAC
888 	error = mac_vnode_check_chroot(td->td_ucred, nd.ni_vp);
889 	if (error != 0)
890 		goto e_vunlock;
891 #endif
892 	VOP_UNLOCK(nd.ni_vp, 0);
893 	error = change_root(nd.ni_vp, td);
894 	vrele(nd.ni_vp);
895 	NDFREE(&nd, NDF_ONLY_PNBUF);
896 	return (error);
897 e_vunlock:
898 	vput(nd.ni_vp);
899 error:
900 	NDFREE(&nd, NDF_ONLY_PNBUF);
901 	return (error);
902 }
903 
904 /*
905  * Common routine for chroot and chdir.  Callers must provide a locked vnode
906  * instance.
907  */
908 int
909 change_dir(vp, td)
910 	struct vnode *vp;
911 	struct thread *td;
912 {
913 #ifdef MAC
914 	int error;
915 #endif
916 
917 	ASSERT_VOP_LOCKED(vp, "change_dir(): vp not locked");
918 	if (vp->v_type != VDIR)
919 		return (ENOTDIR);
920 #ifdef MAC
921 	error = mac_vnode_check_chdir(td->td_ucred, vp);
922 	if (error != 0)
923 		return (error);
924 #endif
925 	return (VOP_ACCESS(vp, VEXEC, td->td_ucred, td));
926 }
927 
928 /*
929  * Common routine for kern_chroot() and jail_attach().  The caller is
930  * responsible for invoking priv_check() and mac_vnode_check_chroot() to
931  * authorize this operation.
932  */
933 int
934 change_root(vp, td)
935 	struct vnode *vp;
936 	struct thread *td;
937 {
938 	struct filedesc *fdp;
939 	struct vnode *oldvp;
940 	int error;
941 
942 	fdp = td->td_proc->p_fd;
943 	FILEDESC_XLOCK(fdp);
944 	if (chroot_allow_open_directories == 0 ||
945 	    (chroot_allow_open_directories == 1 && fdp->fd_rdir != rootvnode)) {
946 		error = chroot_refuse_vdir_fds(fdp);
947 		if (error != 0) {
948 			FILEDESC_XUNLOCK(fdp);
949 			return (error);
950 		}
951 	}
952 	oldvp = fdp->fd_rdir;
953 	fdp->fd_rdir = vp;
954 	VREF(fdp->fd_rdir);
955 	if (!fdp->fd_jdir) {
956 		fdp->fd_jdir = vp;
957 		VREF(fdp->fd_jdir);
958 	}
959 	FILEDESC_XUNLOCK(fdp);
960 	vrele(oldvp);
961 	return (0);
962 }
963 
964 static __inline void
965 flags_to_rights(int flags, cap_rights_t *rightsp)
966 {
967 
968 	if (flags & O_EXEC) {
969 		cap_rights_set(rightsp, CAP_FEXECVE);
970 	} else {
971 		switch ((flags & O_ACCMODE)) {
972 		case O_RDONLY:
973 			cap_rights_set(rightsp, CAP_READ);
974 			break;
975 		case O_RDWR:
976 			cap_rights_set(rightsp, CAP_READ);
977 			/* FALLTHROUGH */
978 		case O_WRONLY:
979 			cap_rights_set(rightsp, CAP_WRITE);
980 			if (!(flags & (O_APPEND | O_TRUNC)))
981 				cap_rights_set(rightsp, CAP_SEEK);
982 			break;
983 		}
984 	}
985 
986 	if (flags & O_CREAT)
987 		cap_rights_set(rightsp, CAP_CREATE);
988 
989 	if (flags & O_TRUNC)
990 		cap_rights_set(rightsp, CAP_FTRUNCATE);
991 
992 	if (flags & (O_SYNC | O_FSYNC))
993 		cap_rights_set(rightsp, CAP_FSYNC);
994 
995 	if (flags & (O_EXLOCK | O_SHLOCK))
996 		cap_rights_set(rightsp, CAP_FLOCK);
997 }
998 
999 /*
1000  * Check permissions, allocate an open file structure, and call the device
1001  * open routine if any.
1002  */
1003 #ifndef _SYS_SYSPROTO_H_
1004 struct open_args {
1005 	char	*path;
1006 	int	flags;
1007 	int	mode;
1008 };
1009 #endif
1010 int
1011 sys_open(td, uap)
1012 	struct thread *td;
1013 	register struct open_args /* {
1014 		char *path;
1015 		int flags;
1016 		int mode;
1017 	} */ *uap;
1018 {
1019 
1020 	return (kern_open(td, uap->path, UIO_USERSPACE, uap->flags, uap->mode));
1021 }
1022 
1023 #ifndef _SYS_SYSPROTO_H_
1024 struct openat_args {
1025 	int	fd;
1026 	char	*path;
1027 	int	flag;
1028 	int	mode;
1029 };
1030 #endif
1031 int
1032 sys_openat(struct thread *td, struct openat_args *uap)
1033 {
1034 
1035 	return (kern_openat(td, uap->fd, uap->path, UIO_USERSPACE, uap->flag,
1036 	    uap->mode));
1037 }
1038 
1039 int
1040 kern_open(struct thread *td, char *path, enum uio_seg pathseg, int flags,
1041     int mode)
1042 {
1043 
1044 	return (kern_openat(td, AT_FDCWD, path, pathseg, flags, mode));
1045 }
1046 
1047 int
1048 kern_openat(struct thread *td, int fd, char *path, enum uio_seg pathseg,
1049     int flags, int mode)
1050 {
1051 	struct proc *p = td->td_proc;
1052 	struct filedesc *fdp = p->p_fd;
1053 	struct file *fp;
1054 	struct vnode *vp;
1055 	struct nameidata nd;
1056 	cap_rights_t rights;
1057 	int cmode, error, indx;
1058 
1059 	indx = -1;
1060 
1061 	AUDIT_ARG_FFLAGS(flags);
1062 	AUDIT_ARG_MODE(mode);
1063 	/* XXX: audit dirfd */
1064 	cap_rights_init(&rights, CAP_LOOKUP);
1065 	flags_to_rights(flags, &rights);
1066 	/*
1067 	 * Only one of the O_EXEC, O_RDONLY, O_WRONLY and O_RDWR flags
1068 	 * may be specified.
1069 	 */
1070 	if (flags & O_EXEC) {
1071 		if (flags & O_ACCMODE)
1072 			return (EINVAL);
1073 	} else if ((flags & O_ACCMODE) == O_ACCMODE) {
1074 		return (EINVAL);
1075 	} else {
1076 		flags = FFLAGS(flags);
1077 	}
1078 
1079 	/*
1080 	 * Allocate the file descriptor, but don't install a descriptor yet.
1081 	 */
1082 	error = falloc_noinstall(td, &fp);
1083 	if (error != 0)
1084 		return (error);
1085 	/*
1086 	 * An extra reference on `fp' has been held for us by
1087 	 * falloc_noinstall().
1088 	 */
1089 	/* Set the flags early so the finit in devfs can pick them up. */
1090 	fp->f_flag = flags & FMASK;
1091 	cmode = ((mode & ~fdp->fd_cmask) & ALLPERMS) & ~S_ISTXT;
1092 	NDINIT_ATRIGHTS(&nd, LOOKUP, FOLLOW | AUDITVNODE1, pathseg, path, fd,
1093 	    &rights, td);
1094 	td->td_dupfd = -1;		/* XXX check for fdopen */
1095 	error = vn_open(&nd, &flags, cmode, fp);
1096 	if (error != 0) {
1097 		/*
1098 		 * If the vn_open replaced the method vector, something
1099 		 * wonderous happened deep below and we just pass it up
1100 		 * pretending we know what we do.
1101 		 */
1102 		if (error == ENXIO && fp->f_ops != &badfileops)
1103 			goto success;
1104 
1105 		/*
1106 		 * Handle special fdopen() case. bleh.
1107 		 *
1108 		 * Don't do this for relative (capability) lookups; we don't
1109 		 * understand exactly what would happen, and we don't think
1110 		 * that it ever should.
1111 		 */
1112 		if (nd.ni_strictrelative == 0 &&
1113 		    (error == ENODEV || error == ENXIO) &&
1114 		    td->td_dupfd >= 0) {
1115 			error = dupfdopen(td, fdp, td->td_dupfd, flags, error,
1116 			    &indx);
1117 			if (error == 0)
1118 				goto success;
1119 		}
1120 
1121 		goto bad;
1122 	}
1123 	td->td_dupfd = 0;
1124 	NDFREE(&nd, NDF_ONLY_PNBUF);
1125 	vp = nd.ni_vp;
1126 
1127 	/*
1128 	 * Store the vnode, for any f_type. Typically, the vnode use
1129 	 * count is decremented by direct call to vn_closefile() for
1130 	 * files that switched type in the cdevsw fdopen() method.
1131 	 */
1132 	fp->f_vnode = vp;
1133 	/*
1134 	 * If the file wasn't claimed by devfs bind it to the normal
1135 	 * vnode operations here.
1136 	 */
1137 	if (fp->f_ops == &badfileops) {
1138 		KASSERT(vp->v_type != VFIFO, ("Unexpected fifo."));
1139 		fp->f_seqcount = 1;
1140 		finit(fp, (flags & FMASK) | (fp->f_flag & FHASLOCK),
1141 		    DTYPE_VNODE, vp, &vnops);
1142 	}
1143 
1144 	VOP_UNLOCK(vp, 0);
1145 	if (flags & O_TRUNC) {
1146 		error = fo_truncate(fp, 0, td->td_ucred, td);
1147 		if (error != 0)
1148 			goto bad;
1149 	}
1150 success:
1151 	/*
1152 	 * If we haven't already installed the FD (for dupfdopen), do so now.
1153 	 */
1154 	if (indx == -1) {
1155 		struct filecaps *fcaps;
1156 
1157 #ifdef CAPABILITIES
1158 		if (nd.ni_strictrelative == 1)
1159 			fcaps = &nd.ni_filecaps;
1160 		else
1161 #endif
1162 			fcaps = NULL;
1163 		error = finstall(td, fp, &indx, flags, fcaps);
1164 		/* On success finstall() consumes fcaps. */
1165 		if (error != 0) {
1166 			filecaps_free(&nd.ni_filecaps);
1167 			goto bad;
1168 		}
1169 	} else {
1170 		filecaps_free(&nd.ni_filecaps);
1171 	}
1172 
1173 	/*
1174 	 * Release our private reference, leaving the one associated with
1175 	 * the descriptor table intact.
1176 	 */
1177 	fdrop(fp, td);
1178 	td->td_retval[0] = indx;
1179 	return (0);
1180 bad:
1181 	KASSERT(indx == -1, ("indx=%d, should be -1", indx));
1182 	fdrop(fp, td);
1183 	return (error);
1184 }
1185 
1186 #ifdef COMPAT_43
1187 /*
1188  * Create a file.
1189  */
1190 #ifndef _SYS_SYSPROTO_H_
1191 struct ocreat_args {
1192 	char	*path;
1193 	int	mode;
1194 };
1195 #endif
1196 int
1197 ocreat(td, uap)
1198 	struct thread *td;
1199 	register struct ocreat_args /* {
1200 		char *path;
1201 		int mode;
1202 	} */ *uap;
1203 {
1204 
1205 	return (kern_open(td, uap->path, UIO_USERSPACE,
1206 	    O_WRONLY | O_CREAT | O_TRUNC, uap->mode));
1207 }
1208 #endif /* COMPAT_43 */
1209 
1210 /*
1211  * Create a special file.
1212  */
1213 #ifndef _SYS_SYSPROTO_H_
1214 struct mknod_args {
1215 	char	*path;
1216 	int	mode;
1217 	int	dev;
1218 };
1219 #endif
1220 int
1221 sys_mknod(td, uap)
1222 	struct thread *td;
1223 	register struct mknod_args /* {
1224 		char *path;
1225 		int mode;
1226 		int dev;
1227 	} */ *uap;
1228 {
1229 
1230 	return (kern_mknod(td, uap->path, UIO_USERSPACE, uap->mode, uap->dev));
1231 }
1232 
1233 #ifndef _SYS_SYSPROTO_H_
1234 struct mknodat_args {
1235 	int	fd;
1236 	char	*path;
1237 	mode_t	mode;
1238 	dev_t	dev;
1239 };
1240 #endif
1241 int
1242 sys_mknodat(struct thread *td, struct mknodat_args *uap)
1243 {
1244 
1245 	return (kern_mknodat(td, uap->fd, uap->path, UIO_USERSPACE, uap->mode,
1246 	    uap->dev));
1247 }
1248 
1249 int
1250 kern_mknod(struct thread *td, char *path, enum uio_seg pathseg, int mode,
1251     int dev)
1252 {
1253 
1254 	return (kern_mknodat(td, AT_FDCWD, path, pathseg, mode, dev));
1255 }
1256 
1257 int
1258 kern_mknodat(struct thread *td, int fd, char *path, enum uio_seg pathseg,
1259     int mode, int dev)
1260 {
1261 	struct vnode *vp;
1262 	struct mount *mp;
1263 	struct vattr vattr;
1264 	struct nameidata nd;
1265 	cap_rights_t rights;
1266 	int error, whiteout = 0;
1267 
1268 	AUDIT_ARG_MODE(mode);
1269 	AUDIT_ARG_DEV(dev);
1270 	switch (mode & S_IFMT) {
1271 	case S_IFCHR:
1272 	case S_IFBLK:
1273 		error = priv_check(td, PRIV_VFS_MKNOD_DEV);
1274 		break;
1275 	case S_IFMT:
1276 		error = priv_check(td, PRIV_VFS_MKNOD_BAD);
1277 		break;
1278 	case S_IFWHT:
1279 		error = priv_check(td, PRIV_VFS_MKNOD_WHT);
1280 		break;
1281 	case S_IFIFO:
1282 		if (dev == 0)
1283 			return (kern_mkfifoat(td, fd, path, pathseg, mode));
1284 		/* FALLTHROUGH */
1285 	default:
1286 		error = EINVAL;
1287 		break;
1288 	}
1289 	if (error != 0)
1290 		return (error);
1291 restart:
1292 	bwillwrite();
1293 	NDINIT_ATRIGHTS(&nd, CREATE, LOCKPARENT | SAVENAME | AUDITVNODE1,
1294 	    pathseg, path, fd, cap_rights_init(&rights, CAP_MKNODAT), td);
1295 	if ((error = namei(&nd)) != 0)
1296 		return (error);
1297 	vp = nd.ni_vp;
1298 	if (vp != NULL) {
1299 		NDFREE(&nd, NDF_ONLY_PNBUF);
1300 		if (vp == nd.ni_dvp)
1301 			vrele(nd.ni_dvp);
1302 		else
1303 			vput(nd.ni_dvp);
1304 		vrele(vp);
1305 		return (EEXIST);
1306 	} else {
1307 		VATTR_NULL(&vattr);
1308 		vattr.va_mode = (mode & ALLPERMS) &
1309 		    ~td->td_proc->p_fd->fd_cmask;
1310 		vattr.va_rdev = dev;
1311 		whiteout = 0;
1312 
1313 		switch (mode & S_IFMT) {
1314 		case S_IFMT:	/* used by badsect to flag bad sectors */
1315 			vattr.va_type = VBAD;
1316 			break;
1317 		case S_IFCHR:
1318 			vattr.va_type = VCHR;
1319 			break;
1320 		case S_IFBLK:
1321 			vattr.va_type = VBLK;
1322 			break;
1323 		case S_IFWHT:
1324 			whiteout = 1;
1325 			break;
1326 		default:
1327 			panic("kern_mknod: invalid mode");
1328 		}
1329 	}
1330 	if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
1331 		NDFREE(&nd, NDF_ONLY_PNBUF);
1332 		vput(nd.ni_dvp);
1333 		if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
1334 			return (error);
1335 		goto restart;
1336 	}
1337 #ifdef MAC
1338 	if (error == 0 && !whiteout)
1339 		error = mac_vnode_check_create(td->td_ucred, nd.ni_dvp,
1340 		    &nd.ni_cnd, &vattr);
1341 #endif
1342 	if (error == 0) {
1343 		if (whiteout)
1344 			error = VOP_WHITEOUT(nd.ni_dvp, &nd.ni_cnd, CREATE);
1345 		else {
1346 			error = VOP_MKNOD(nd.ni_dvp, &nd.ni_vp,
1347 						&nd.ni_cnd, &vattr);
1348 			if (error == 0)
1349 				vput(nd.ni_vp);
1350 		}
1351 	}
1352 	NDFREE(&nd, NDF_ONLY_PNBUF);
1353 	vput(nd.ni_dvp);
1354 	vn_finished_write(mp);
1355 	return (error);
1356 }
1357 
1358 /*
1359  * Create a named pipe.
1360  */
1361 #ifndef _SYS_SYSPROTO_H_
1362 struct mkfifo_args {
1363 	char	*path;
1364 	int	mode;
1365 };
1366 #endif
1367 int
1368 sys_mkfifo(td, uap)
1369 	struct thread *td;
1370 	register struct mkfifo_args /* {
1371 		char *path;
1372 		int mode;
1373 	} */ *uap;
1374 {
1375 
1376 	return (kern_mkfifo(td, uap->path, UIO_USERSPACE, uap->mode));
1377 }
1378 
1379 #ifndef _SYS_SYSPROTO_H_
1380 struct mkfifoat_args {
1381 	int	fd;
1382 	char	*path;
1383 	mode_t	mode;
1384 };
1385 #endif
1386 int
1387 sys_mkfifoat(struct thread *td, struct mkfifoat_args *uap)
1388 {
1389 
1390 	return (kern_mkfifoat(td, uap->fd, uap->path, UIO_USERSPACE,
1391 	    uap->mode));
1392 }
1393 
1394 int
1395 kern_mkfifo(struct thread *td, char *path, enum uio_seg pathseg, int mode)
1396 {
1397 
1398 	return (kern_mkfifoat(td, AT_FDCWD, path, pathseg, mode));
1399 }
1400 
1401 int
1402 kern_mkfifoat(struct thread *td, int fd, char *path, enum uio_seg pathseg,
1403     int mode)
1404 {
1405 	struct mount *mp;
1406 	struct vattr vattr;
1407 	struct nameidata nd;
1408 	cap_rights_t rights;
1409 	int error;
1410 
1411 	AUDIT_ARG_MODE(mode);
1412 restart:
1413 	bwillwrite();
1414 	NDINIT_ATRIGHTS(&nd, CREATE, LOCKPARENT | SAVENAME | AUDITVNODE1,
1415 	    pathseg, path, fd, cap_rights_init(&rights, CAP_MKFIFOAT), td);
1416 	if ((error = namei(&nd)) != 0)
1417 		return (error);
1418 	if (nd.ni_vp != NULL) {
1419 		NDFREE(&nd, NDF_ONLY_PNBUF);
1420 		if (nd.ni_vp == nd.ni_dvp)
1421 			vrele(nd.ni_dvp);
1422 		else
1423 			vput(nd.ni_dvp);
1424 		vrele(nd.ni_vp);
1425 		return (EEXIST);
1426 	}
1427 	if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
1428 		NDFREE(&nd, NDF_ONLY_PNBUF);
1429 		vput(nd.ni_dvp);
1430 		if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
1431 			return (error);
1432 		goto restart;
1433 	}
1434 	VATTR_NULL(&vattr);
1435 	vattr.va_type = VFIFO;
1436 	vattr.va_mode = (mode & ALLPERMS) & ~td->td_proc->p_fd->fd_cmask;
1437 #ifdef MAC
1438 	error = mac_vnode_check_create(td->td_ucred, nd.ni_dvp, &nd.ni_cnd,
1439 	    &vattr);
1440 	if (error != 0)
1441 		goto out;
1442 #endif
1443 	error = VOP_MKNOD(nd.ni_dvp, &nd.ni_vp, &nd.ni_cnd, &vattr);
1444 	if (error == 0)
1445 		vput(nd.ni_vp);
1446 #ifdef MAC
1447 out:
1448 #endif
1449 	vput(nd.ni_dvp);
1450 	vn_finished_write(mp);
1451 	NDFREE(&nd, NDF_ONLY_PNBUF);
1452 	return (error);
1453 }
1454 
1455 /*
1456  * Make a hard file link.
1457  */
1458 #ifndef _SYS_SYSPROTO_H_
1459 struct link_args {
1460 	char	*path;
1461 	char	*link;
1462 };
1463 #endif
1464 int
1465 sys_link(td, uap)
1466 	struct thread *td;
1467 	register struct link_args /* {
1468 		char *path;
1469 		char *link;
1470 	} */ *uap;
1471 {
1472 
1473 	return (kern_link(td, uap->path, uap->link, UIO_USERSPACE));
1474 }
1475 
1476 #ifndef _SYS_SYSPROTO_H_
1477 struct linkat_args {
1478 	int	fd1;
1479 	char	*path1;
1480 	int	fd2;
1481 	char	*path2;
1482 	int	flag;
1483 };
1484 #endif
1485 int
1486 sys_linkat(struct thread *td, struct linkat_args *uap)
1487 {
1488 	int flag;
1489 
1490 	flag = uap->flag;
1491 	if (flag & ~AT_SYMLINK_FOLLOW)
1492 		return (EINVAL);
1493 
1494 	return (kern_linkat(td, uap->fd1, uap->fd2, uap->path1, uap->path2,
1495 	    UIO_USERSPACE, (flag & AT_SYMLINK_FOLLOW) ? FOLLOW : NOFOLLOW));
1496 }
1497 
1498 int hardlink_check_uid = 0;
1499 SYSCTL_INT(_security_bsd, OID_AUTO, hardlink_check_uid, CTLFLAG_RW,
1500     &hardlink_check_uid, 0,
1501     "Unprivileged processes cannot create hard links to files owned by other "
1502     "users");
1503 static int hardlink_check_gid = 0;
1504 SYSCTL_INT(_security_bsd, OID_AUTO, hardlink_check_gid, CTLFLAG_RW,
1505     &hardlink_check_gid, 0,
1506     "Unprivileged processes cannot create hard links to files owned by other "
1507     "groups");
1508 
1509 static int
1510 can_hardlink(struct vnode *vp, struct ucred *cred)
1511 {
1512 	struct vattr va;
1513 	int error;
1514 
1515 	if (!hardlink_check_uid && !hardlink_check_gid)
1516 		return (0);
1517 
1518 	error = VOP_GETATTR(vp, &va, cred);
1519 	if (error != 0)
1520 		return (error);
1521 
1522 	if (hardlink_check_uid && cred->cr_uid != va.va_uid) {
1523 		error = priv_check_cred(cred, PRIV_VFS_LINK, 0);
1524 		if (error != 0)
1525 			return (error);
1526 	}
1527 
1528 	if (hardlink_check_gid && !groupmember(va.va_gid, cred)) {
1529 		error = priv_check_cred(cred, PRIV_VFS_LINK, 0);
1530 		if (error != 0)
1531 			return (error);
1532 	}
1533 
1534 	return (0);
1535 }
1536 
1537 int
1538 kern_link(struct thread *td, char *path, char *link, enum uio_seg segflg)
1539 {
1540 
1541 	return (kern_linkat(td, AT_FDCWD, AT_FDCWD, path,link, segflg, FOLLOW));
1542 }
1543 
1544 int
1545 kern_linkat(struct thread *td, int fd1, int fd2, char *path1, char *path2,
1546     enum uio_seg segflg, int follow)
1547 {
1548 	struct vnode *vp;
1549 	struct mount *mp;
1550 	struct nameidata nd;
1551 	cap_rights_t rights;
1552 	int error;
1553 
1554 	bwillwrite();
1555 	NDINIT_AT(&nd, LOOKUP, follow | AUDITVNODE1, segflg, path1, fd1, td);
1556 
1557 	if ((error = namei(&nd)) != 0)
1558 		return (error);
1559 	NDFREE(&nd, NDF_ONLY_PNBUF);
1560 	vp = nd.ni_vp;
1561 	if (vp->v_type == VDIR) {
1562 		vrele(vp);
1563 		return (EPERM);		/* POSIX */
1564 	}
1565 	if ((error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0) {
1566 		vrele(vp);
1567 		return (error);
1568 	}
1569 	NDINIT_ATRIGHTS(&nd, CREATE, LOCKPARENT | SAVENAME | AUDITVNODE2,
1570 	    segflg, path2, fd2, cap_rights_init(&rights, CAP_LINKAT), td);
1571 	if ((error = namei(&nd)) == 0) {
1572 		if (nd.ni_vp != NULL) {
1573 			if (nd.ni_dvp == nd.ni_vp)
1574 				vrele(nd.ni_dvp);
1575 			else
1576 				vput(nd.ni_dvp);
1577 			vrele(nd.ni_vp);
1578 			error = EEXIST;
1579 		} else if ((error = vn_lock(vp, LK_EXCLUSIVE | LK_RETRY))
1580 		    == 0) {
1581 			error = can_hardlink(vp, td->td_ucred);
1582 			if (error == 0)
1583 #ifdef MAC
1584 				error = mac_vnode_check_link(td->td_ucred,
1585 				    nd.ni_dvp, vp, &nd.ni_cnd);
1586 			if (error == 0)
1587 #endif
1588 				error = VOP_LINK(nd.ni_dvp, vp, &nd.ni_cnd);
1589 			VOP_UNLOCK(vp, 0);
1590 			vput(nd.ni_dvp);
1591 		}
1592 		NDFREE(&nd, NDF_ONLY_PNBUF);
1593 	}
1594 	vrele(vp);
1595 	vn_finished_write(mp);
1596 	return (error);
1597 }
1598 
1599 /*
1600  * Make a symbolic link.
1601  */
1602 #ifndef _SYS_SYSPROTO_H_
1603 struct symlink_args {
1604 	char	*path;
1605 	char	*link;
1606 };
1607 #endif
1608 int
1609 sys_symlink(td, uap)
1610 	struct thread *td;
1611 	register struct symlink_args /* {
1612 		char *path;
1613 		char *link;
1614 	} */ *uap;
1615 {
1616 
1617 	return (kern_symlink(td, uap->path, uap->link, UIO_USERSPACE));
1618 }
1619 
1620 #ifndef _SYS_SYSPROTO_H_
1621 struct symlinkat_args {
1622 	char	*path;
1623 	int	fd;
1624 	char	*path2;
1625 };
1626 #endif
1627 int
1628 sys_symlinkat(struct thread *td, struct symlinkat_args *uap)
1629 {
1630 
1631 	return (kern_symlinkat(td, uap->path1, uap->fd, uap->path2,
1632 	    UIO_USERSPACE));
1633 }
1634 
1635 int
1636 kern_symlink(struct thread *td, char *path, char *link, enum uio_seg segflg)
1637 {
1638 
1639 	return (kern_symlinkat(td, path, AT_FDCWD, link, segflg));
1640 }
1641 
1642 int
1643 kern_symlinkat(struct thread *td, char *path1, int fd, char *path2,
1644     enum uio_seg segflg)
1645 {
1646 	struct mount *mp;
1647 	struct vattr vattr;
1648 	char *syspath;
1649 	struct nameidata nd;
1650 	int error;
1651 	cap_rights_t rights;
1652 
1653 	if (segflg == UIO_SYSSPACE) {
1654 		syspath = path1;
1655 	} else {
1656 		syspath = uma_zalloc(namei_zone, M_WAITOK);
1657 		if ((error = copyinstr(path1, syspath, MAXPATHLEN, NULL)) != 0)
1658 			goto out;
1659 	}
1660 	AUDIT_ARG_TEXT(syspath);
1661 restart:
1662 	bwillwrite();
1663 	NDINIT_ATRIGHTS(&nd, CREATE, LOCKPARENT | SAVENAME | AUDITVNODE1,
1664 	    segflg, path2, fd, cap_rights_init(&rights, CAP_SYMLINKAT), td);
1665 	if ((error = namei(&nd)) != 0)
1666 		goto out;
1667 	if (nd.ni_vp) {
1668 		NDFREE(&nd, NDF_ONLY_PNBUF);
1669 		if (nd.ni_vp == nd.ni_dvp)
1670 			vrele(nd.ni_dvp);
1671 		else
1672 			vput(nd.ni_dvp);
1673 		vrele(nd.ni_vp);
1674 		error = EEXIST;
1675 		goto out;
1676 	}
1677 	if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
1678 		NDFREE(&nd, NDF_ONLY_PNBUF);
1679 		vput(nd.ni_dvp);
1680 		if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
1681 			goto out;
1682 		goto restart;
1683 	}
1684 	VATTR_NULL(&vattr);
1685 	vattr.va_mode = ACCESSPERMS &~ td->td_proc->p_fd->fd_cmask;
1686 #ifdef MAC
1687 	vattr.va_type = VLNK;
1688 	error = mac_vnode_check_create(td->td_ucred, nd.ni_dvp, &nd.ni_cnd,
1689 	    &vattr);
1690 	if (error != 0)
1691 		goto out2;
1692 #endif
1693 	error = VOP_SYMLINK(nd.ni_dvp, &nd.ni_vp, &nd.ni_cnd, &vattr, syspath);
1694 	if (error == 0)
1695 		vput(nd.ni_vp);
1696 #ifdef MAC
1697 out2:
1698 #endif
1699 	NDFREE(&nd, NDF_ONLY_PNBUF);
1700 	vput(nd.ni_dvp);
1701 	vn_finished_write(mp);
1702 out:
1703 	if (segflg != UIO_SYSSPACE)
1704 		uma_zfree(namei_zone, syspath);
1705 	return (error);
1706 }
1707 
1708 /*
1709  * Delete a whiteout from the filesystem.
1710  */
1711 int
1712 sys_undelete(td, uap)
1713 	struct thread *td;
1714 	register struct undelete_args /* {
1715 		char *path;
1716 	} */ *uap;
1717 {
1718 	struct mount *mp;
1719 	struct nameidata nd;
1720 	int error;
1721 
1722 restart:
1723 	bwillwrite();
1724 	NDINIT(&nd, DELETE, LOCKPARENT | DOWHITEOUT | AUDITVNODE1,
1725 	    UIO_USERSPACE, uap->path, td);
1726 	error = namei(&nd);
1727 	if (error != 0)
1728 		return (error);
1729 
1730 	if (nd.ni_vp != NULLVP || !(nd.ni_cnd.cn_flags & ISWHITEOUT)) {
1731 		NDFREE(&nd, NDF_ONLY_PNBUF);
1732 		if (nd.ni_vp == nd.ni_dvp)
1733 			vrele(nd.ni_dvp);
1734 		else
1735 			vput(nd.ni_dvp);
1736 		if (nd.ni_vp)
1737 			vrele(nd.ni_vp);
1738 		return (EEXIST);
1739 	}
1740 	if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
1741 		NDFREE(&nd, NDF_ONLY_PNBUF);
1742 		vput(nd.ni_dvp);
1743 		if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
1744 			return (error);
1745 		goto restart;
1746 	}
1747 	error = VOP_WHITEOUT(nd.ni_dvp, &nd.ni_cnd, DELETE);
1748 	NDFREE(&nd, NDF_ONLY_PNBUF);
1749 	vput(nd.ni_dvp);
1750 	vn_finished_write(mp);
1751 	return (error);
1752 }
1753 
1754 /*
1755  * Delete a name from the filesystem.
1756  */
1757 #ifndef _SYS_SYSPROTO_H_
1758 struct unlink_args {
1759 	char	*path;
1760 };
1761 #endif
1762 int
1763 sys_unlink(td, uap)
1764 	struct thread *td;
1765 	struct unlink_args /* {
1766 		char *path;
1767 	} */ *uap;
1768 {
1769 
1770 	return (kern_unlink(td, uap->path, UIO_USERSPACE));
1771 }
1772 
1773 #ifndef _SYS_SYSPROTO_H_
1774 struct unlinkat_args {
1775 	int	fd;
1776 	char	*path;
1777 	int	flag;
1778 };
1779 #endif
1780 int
1781 sys_unlinkat(struct thread *td, struct unlinkat_args *uap)
1782 {
1783 	int flag = uap->flag;
1784 	int fd = uap->fd;
1785 	char *path = uap->path;
1786 
1787 	if (flag & ~AT_REMOVEDIR)
1788 		return (EINVAL);
1789 
1790 	if (flag & AT_REMOVEDIR)
1791 		return (kern_rmdirat(td, fd, path, UIO_USERSPACE));
1792 	else
1793 		return (kern_unlinkat(td, fd, path, UIO_USERSPACE, 0));
1794 }
1795 
1796 int
1797 kern_unlink(struct thread *td, char *path, enum uio_seg pathseg)
1798 {
1799 
1800 	return (kern_unlinkat(td, AT_FDCWD, path, pathseg, 0));
1801 }
1802 
1803 int
1804 kern_unlinkat(struct thread *td, int fd, char *path, enum uio_seg pathseg,
1805     ino_t oldinum)
1806 {
1807 	struct mount *mp;
1808 	struct vnode *vp;
1809 	struct nameidata nd;
1810 	struct stat sb;
1811 	cap_rights_t rights;
1812 	int error;
1813 
1814 restart:
1815 	bwillwrite();
1816 	NDINIT_ATRIGHTS(&nd, DELETE, LOCKPARENT | LOCKLEAF | AUDITVNODE1,
1817 	    pathseg, path, fd, cap_rights_init(&rights, CAP_UNLINKAT), td);
1818 	if ((error = namei(&nd)) != 0)
1819 		return (error == EINVAL ? EPERM : error);
1820 	vp = nd.ni_vp;
1821 	if (vp->v_type == VDIR && oldinum == 0) {
1822 		error = EPERM;		/* POSIX */
1823 	} else if (oldinum != 0 &&
1824 		  ((error = vn_stat(vp, &sb, td->td_ucred, NOCRED, td)) == 0) &&
1825 		  sb.st_ino != oldinum) {
1826 			error = EIDRM;	/* Identifier removed */
1827 	} else {
1828 		/*
1829 		 * The root of a mounted filesystem cannot be deleted.
1830 		 *
1831 		 * XXX: can this only be a VDIR case?
1832 		 */
1833 		if (vp->v_vflag & VV_ROOT)
1834 			error = EBUSY;
1835 	}
1836 	if (error == 0) {
1837 		if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
1838 			NDFREE(&nd, NDF_ONLY_PNBUF);
1839 			vput(nd.ni_dvp);
1840 			if (vp == nd.ni_dvp)
1841 				vrele(vp);
1842 			else
1843 				vput(vp);
1844 			if ((error = vn_start_write(NULL, &mp,
1845 			    V_XSLEEP | PCATCH)) != 0)
1846 				return (error);
1847 			goto restart;
1848 		}
1849 #ifdef MAC
1850 		error = mac_vnode_check_unlink(td->td_ucred, nd.ni_dvp, vp,
1851 		    &nd.ni_cnd);
1852 		if (error != 0)
1853 			goto out;
1854 #endif
1855 		vfs_notify_upper(vp, VFS_NOTIFY_UPPER_UNLINK);
1856 		error = VOP_REMOVE(nd.ni_dvp, vp, &nd.ni_cnd);
1857 #ifdef MAC
1858 out:
1859 #endif
1860 		vn_finished_write(mp);
1861 	}
1862 	NDFREE(&nd, NDF_ONLY_PNBUF);
1863 	vput(nd.ni_dvp);
1864 	if (vp == nd.ni_dvp)
1865 		vrele(vp);
1866 	else
1867 		vput(vp);
1868 	return (error);
1869 }
1870 
1871 /*
1872  * Reposition read/write file offset.
1873  */
1874 #ifndef _SYS_SYSPROTO_H_
1875 struct lseek_args {
1876 	int	fd;
1877 	int	pad;
1878 	off_t	offset;
1879 	int	whence;
1880 };
1881 #endif
1882 int
1883 sys_lseek(td, uap)
1884 	struct thread *td;
1885 	register struct lseek_args /* {
1886 		int fd;
1887 		int pad;
1888 		off_t offset;
1889 		int whence;
1890 	} */ *uap;
1891 {
1892 	struct file *fp;
1893 	cap_rights_t rights;
1894 	int error;
1895 
1896 	AUDIT_ARG_FD(uap->fd);
1897 	error = fget(td, uap->fd, cap_rights_init(&rights, CAP_SEEK), &fp);
1898 	if (error != 0)
1899 		return (error);
1900 	error = (fp->f_ops->fo_flags & DFLAG_SEEKABLE) != 0 ?
1901 	    fo_seek(fp, uap->offset, uap->whence, td) : ESPIPE;
1902 	fdrop(fp, td);
1903 	return (error);
1904 }
1905 
1906 #if defined(COMPAT_43)
1907 /*
1908  * Reposition read/write file offset.
1909  */
1910 #ifndef _SYS_SYSPROTO_H_
1911 struct olseek_args {
1912 	int	fd;
1913 	long	offset;
1914 	int	whence;
1915 };
1916 #endif
1917 int
1918 olseek(td, uap)
1919 	struct thread *td;
1920 	register struct olseek_args /* {
1921 		int fd;
1922 		long offset;
1923 		int whence;
1924 	} */ *uap;
1925 {
1926 	struct lseek_args /* {
1927 		int fd;
1928 		int pad;
1929 		off_t offset;
1930 		int whence;
1931 	} */ nuap;
1932 
1933 	nuap.fd = uap->fd;
1934 	nuap.offset = uap->offset;
1935 	nuap.whence = uap->whence;
1936 	return (sys_lseek(td, &nuap));
1937 }
1938 #endif /* COMPAT_43 */
1939 
1940 /* Version with the 'pad' argument */
1941 int
1942 freebsd6_lseek(td, uap)
1943 	struct thread *td;
1944 	register struct freebsd6_lseek_args *uap;
1945 {
1946 	struct lseek_args ouap;
1947 
1948 	ouap.fd = uap->fd;
1949 	ouap.offset = uap->offset;
1950 	ouap.whence = uap->whence;
1951 	return (sys_lseek(td, &ouap));
1952 }
1953 
1954 /*
1955  * Check access permissions using passed credentials.
1956  */
1957 static int
1958 vn_access(vp, user_flags, cred, td)
1959 	struct vnode	*vp;
1960 	int		user_flags;
1961 	struct ucred	*cred;
1962 	struct thread	*td;
1963 {
1964 	accmode_t accmode;
1965 	int error;
1966 
1967 	/* Flags == 0 means only check for existence. */
1968 	error = 0;
1969 	if (user_flags) {
1970 		accmode = 0;
1971 		if (user_flags & R_OK)
1972 			accmode |= VREAD;
1973 		if (user_flags & W_OK)
1974 			accmode |= VWRITE;
1975 		if (user_flags & X_OK)
1976 			accmode |= VEXEC;
1977 #ifdef MAC
1978 		error = mac_vnode_check_access(cred, vp, accmode);
1979 		if (error != 0)
1980 			return (error);
1981 #endif
1982 		if ((accmode & VWRITE) == 0 || (error = vn_writechk(vp)) == 0)
1983 			error = VOP_ACCESS(vp, accmode, cred, td);
1984 	}
1985 	return (error);
1986 }
1987 
1988 /*
1989  * Check access permissions using "real" credentials.
1990  */
1991 #ifndef _SYS_SYSPROTO_H_
1992 struct access_args {
1993 	char	*path;
1994 	int	amode;
1995 };
1996 #endif
1997 int
1998 sys_access(td, uap)
1999 	struct thread *td;
2000 	register struct access_args /* {
2001 		char *path;
2002 		int amode;
2003 	} */ *uap;
2004 {
2005 
2006 	return (kern_access(td, uap->path, UIO_USERSPACE, uap->amode));
2007 }
2008 
2009 #ifndef _SYS_SYSPROTO_H_
2010 struct faccessat_args {
2011 	int	dirfd;
2012 	char	*path;
2013 	int	amode;
2014 	int	flag;
2015 }
2016 #endif
2017 int
2018 sys_faccessat(struct thread *td, struct faccessat_args *uap)
2019 {
2020 
2021 	if (uap->flag & ~AT_EACCESS)
2022 		return (EINVAL);
2023 	return (kern_accessat(td, uap->fd, uap->path, UIO_USERSPACE, uap->flag,
2024 	    uap->amode));
2025 }
2026 
2027 int
2028 kern_access(struct thread *td, char *path, enum uio_seg pathseg, int amode)
2029 {
2030 
2031 	return (kern_accessat(td, AT_FDCWD, path, pathseg, 0, amode));
2032 }
2033 
2034 int
2035 kern_accessat(struct thread *td, int fd, char *path, enum uio_seg pathseg,
2036     int flag, int amode)
2037 {
2038 	struct ucred *cred, *tmpcred;
2039 	struct vnode *vp;
2040 	struct nameidata nd;
2041 	cap_rights_t rights;
2042 	int error;
2043 
2044 	/*
2045 	 * Create and modify a temporary credential instead of one that
2046 	 * is potentially shared.
2047 	 */
2048 	if (!(flag & AT_EACCESS)) {
2049 		cred = td->td_ucred;
2050 		tmpcred = crdup(cred);
2051 		tmpcred->cr_uid = cred->cr_ruid;
2052 		tmpcred->cr_groups[0] = cred->cr_rgid;
2053 		td->td_ucred = tmpcred;
2054 	} else
2055 		cred = tmpcred = td->td_ucred;
2056 	AUDIT_ARG_VALUE(amode);
2057 	NDINIT_ATRIGHTS(&nd, LOOKUP, FOLLOW | LOCKSHARED | LOCKLEAF |
2058 	    AUDITVNODE1, pathseg, path, fd, cap_rights_init(&rights, CAP_FSTAT),
2059 	    td);
2060 	if ((error = namei(&nd)) != 0)
2061 		goto out1;
2062 	vp = nd.ni_vp;
2063 
2064 	error = vn_access(vp, amode, tmpcred, td);
2065 	NDFREE(&nd, NDF_ONLY_PNBUF);
2066 	vput(vp);
2067 out1:
2068 	if (!(flag & AT_EACCESS)) {
2069 		td->td_ucred = cred;
2070 		crfree(tmpcred);
2071 	}
2072 	return (error);
2073 }
2074 
2075 /*
2076  * Check access permissions using "effective" credentials.
2077  */
2078 #ifndef _SYS_SYSPROTO_H_
2079 struct eaccess_args {
2080 	char	*path;
2081 	int	amode;
2082 };
2083 #endif
2084 int
2085 sys_eaccess(td, uap)
2086 	struct thread *td;
2087 	register struct eaccess_args /* {
2088 		char *path;
2089 		int amode;
2090 	} */ *uap;
2091 {
2092 
2093 	return (kern_eaccess(td, uap->path, UIO_USERSPACE, uap->amode));
2094 }
2095 
2096 int
2097 kern_eaccess(struct thread *td, char *path, enum uio_seg pathseg, int amode)
2098 {
2099 
2100 	return (kern_accessat(td, AT_FDCWD, path, pathseg, AT_EACCESS, amode));
2101 }
2102 
2103 #if defined(COMPAT_43)
2104 /*
2105  * Get file status; this version follows links.
2106  */
2107 #ifndef _SYS_SYSPROTO_H_
2108 struct ostat_args {
2109 	char	*path;
2110 	struct ostat *ub;
2111 };
2112 #endif
2113 int
2114 ostat(td, uap)
2115 	struct thread *td;
2116 	register struct ostat_args /* {
2117 		char *path;
2118 		struct ostat *ub;
2119 	} */ *uap;
2120 {
2121 	struct stat sb;
2122 	struct ostat osb;
2123 	int error;
2124 
2125 	error = kern_stat(td, uap->path, UIO_USERSPACE, &sb);
2126 	if (error != 0)
2127 		return (error);
2128 	cvtstat(&sb, &osb);
2129 	return (copyout(&osb, uap->ub, sizeof (osb)));
2130 }
2131 
2132 /*
2133  * Get file status; this version does not follow links.
2134  */
2135 #ifndef _SYS_SYSPROTO_H_
2136 struct olstat_args {
2137 	char	*path;
2138 	struct ostat *ub;
2139 };
2140 #endif
2141 int
2142 olstat(td, uap)
2143 	struct thread *td;
2144 	register struct olstat_args /* {
2145 		char *path;
2146 		struct ostat *ub;
2147 	} */ *uap;
2148 {
2149 	struct stat sb;
2150 	struct ostat osb;
2151 	int error;
2152 
2153 	error = kern_lstat(td, uap->path, UIO_USERSPACE, &sb);
2154 	if (error != 0)
2155 		return (error);
2156 	cvtstat(&sb, &osb);
2157 	return (copyout(&osb, uap->ub, sizeof (osb)));
2158 }
2159 
2160 /*
2161  * Convert from an old to a new stat structure.
2162  */
2163 void
2164 cvtstat(st, ost)
2165 	struct stat *st;
2166 	struct ostat *ost;
2167 {
2168 
2169 	ost->st_dev = st->st_dev;
2170 	ost->st_ino = st->st_ino;
2171 	ost->st_mode = st->st_mode;
2172 	ost->st_nlink = st->st_nlink;
2173 	ost->st_uid = st->st_uid;
2174 	ost->st_gid = st->st_gid;
2175 	ost->st_rdev = st->st_rdev;
2176 	if (st->st_size < (quad_t)1 << 32)
2177 		ost->st_size = st->st_size;
2178 	else
2179 		ost->st_size = -2;
2180 	ost->st_atim = st->st_atim;
2181 	ost->st_mtim = st->st_mtim;
2182 	ost->st_ctim = st->st_ctim;
2183 	ost->st_blksize = st->st_blksize;
2184 	ost->st_blocks = st->st_blocks;
2185 	ost->st_flags = st->st_flags;
2186 	ost->st_gen = st->st_gen;
2187 }
2188 #endif /* COMPAT_43 */
2189 
2190 /*
2191  * Get file status; this version follows links.
2192  */
2193 #ifndef _SYS_SYSPROTO_H_
2194 struct stat_args {
2195 	char	*path;
2196 	struct stat *ub;
2197 };
2198 #endif
2199 int
2200 sys_stat(td, uap)
2201 	struct thread *td;
2202 	register struct stat_args /* {
2203 		char *path;
2204 		struct stat *ub;
2205 	} */ *uap;
2206 {
2207 	struct stat sb;
2208 	int error;
2209 
2210 	error = kern_stat(td, uap->path, UIO_USERSPACE, &sb);
2211 	if (error == 0)
2212 		error = copyout(&sb, uap->ub, sizeof (sb));
2213 	return (error);
2214 }
2215 
2216 #ifndef _SYS_SYSPROTO_H_
2217 struct fstatat_args {
2218 	int	fd;
2219 	char	*path;
2220 	struct stat	*buf;
2221 	int	flag;
2222 }
2223 #endif
2224 int
2225 sys_fstatat(struct thread *td, struct fstatat_args *uap)
2226 {
2227 	struct stat sb;
2228 	int error;
2229 
2230 	error = kern_statat(td, uap->flag, uap->fd, uap->path,
2231 	    UIO_USERSPACE, &sb);
2232 	if (error == 0)
2233 		error = copyout(&sb, uap->buf, sizeof (sb));
2234 	return (error);
2235 }
2236 
2237 int
2238 kern_stat(struct thread *td, char *path, enum uio_seg pathseg, struct stat *sbp)
2239 {
2240 
2241 	return (kern_statat(td, 0, AT_FDCWD, path, pathseg, sbp));
2242 }
2243 
2244 int
2245 kern_statat(struct thread *td, int flag, int fd, char *path,
2246     enum uio_seg pathseg, struct stat *sbp)
2247 {
2248 
2249 	return (kern_statat_vnhook(td, flag, fd, path, pathseg, sbp, NULL));
2250 }
2251 
2252 int
2253 kern_statat_vnhook(struct thread *td, int flag, int fd, char *path,
2254     enum uio_seg pathseg, struct stat *sbp,
2255     void (*hook)(struct vnode *vp, struct stat *sbp))
2256 {
2257 	struct nameidata nd;
2258 	struct stat sb;
2259 	cap_rights_t rights;
2260 	int error;
2261 
2262 	if (flag & ~AT_SYMLINK_NOFOLLOW)
2263 		return (EINVAL);
2264 
2265 	NDINIT_ATRIGHTS(&nd, LOOKUP, ((flag & AT_SYMLINK_NOFOLLOW) ? NOFOLLOW :
2266 	    FOLLOW) | LOCKSHARED | LOCKLEAF | AUDITVNODE1, pathseg, path, fd,
2267 	    cap_rights_init(&rights, CAP_FSTAT), td);
2268 
2269 	if ((error = namei(&nd)) != 0)
2270 		return (error);
2271 	error = vn_stat(nd.ni_vp, &sb, td->td_ucred, NOCRED, td);
2272 	if (error == 0) {
2273 		SDT_PROBE(vfs, , stat, mode, path, sb.st_mode, 0, 0, 0);
2274 		if (S_ISREG(sb.st_mode))
2275 			SDT_PROBE(vfs, , stat, reg, path, pathseg, 0, 0, 0);
2276 		if (__predict_false(hook != NULL))
2277 			hook(nd.ni_vp, &sb);
2278 	}
2279 	NDFREE(&nd, NDF_ONLY_PNBUF);
2280 	vput(nd.ni_vp);
2281 	if (error != 0)
2282 		return (error);
2283 	*sbp = sb;
2284 #ifdef KTRACE
2285 	if (KTRPOINT(td, KTR_STRUCT))
2286 		ktrstat(&sb);
2287 #endif
2288 	return (0);
2289 }
2290 
2291 /*
2292  * Get file status; this version does not follow links.
2293  */
2294 #ifndef _SYS_SYSPROTO_H_
2295 struct lstat_args {
2296 	char	*path;
2297 	struct stat *ub;
2298 };
2299 #endif
2300 int
2301 sys_lstat(td, uap)
2302 	struct thread *td;
2303 	register struct lstat_args /* {
2304 		char *path;
2305 		struct stat *ub;
2306 	} */ *uap;
2307 {
2308 	struct stat sb;
2309 	int error;
2310 
2311 	error = kern_lstat(td, uap->path, UIO_USERSPACE, &sb);
2312 	if (error == 0)
2313 		error = copyout(&sb, uap->ub, sizeof (sb));
2314 	return (error);
2315 }
2316 
2317 int
2318 kern_lstat(struct thread *td, char *path, enum uio_seg pathseg, struct stat *sbp)
2319 {
2320 
2321 	return (kern_statat(td, AT_SYMLINK_NOFOLLOW, AT_FDCWD, path, pathseg,
2322 	    sbp));
2323 }
2324 
2325 /*
2326  * Implementation of the NetBSD [l]stat() functions.
2327  */
2328 void
2329 cvtnstat(sb, nsb)
2330 	struct stat *sb;
2331 	struct nstat *nsb;
2332 {
2333 
2334 	bzero(nsb, sizeof *nsb);
2335 	nsb->st_dev = sb->st_dev;
2336 	nsb->st_ino = sb->st_ino;
2337 	nsb->st_mode = sb->st_mode;
2338 	nsb->st_nlink = sb->st_nlink;
2339 	nsb->st_uid = sb->st_uid;
2340 	nsb->st_gid = sb->st_gid;
2341 	nsb->st_rdev = sb->st_rdev;
2342 	nsb->st_atim = sb->st_atim;
2343 	nsb->st_mtim = sb->st_mtim;
2344 	nsb->st_ctim = sb->st_ctim;
2345 	nsb->st_size = sb->st_size;
2346 	nsb->st_blocks = sb->st_blocks;
2347 	nsb->st_blksize = sb->st_blksize;
2348 	nsb->st_flags = sb->st_flags;
2349 	nsb->st_gen = sb->st_gen;
2350 	nsb->st_birthtim = sb->st_birthtim;
2351 }
2352 
2353 #ifndef _SYS_SYSPROTO_H_
2354 struct nstat_args {
2355 	char	*path;
2356 	struct nstat *ub;
2357 };
2358 #endif
2359 int
2360 sys_nstat(td, uap)
2361 	struct thread *td;
2362 	register struct nstat_args /* {
2363 		char *path;
2364 		struct nstat *ub;
2365 	} */ *uap;
2366 {
2367 	struct stat sb;
2368 	struct nstat nsb;
2369 	int error;
2370 
2371 	error = kern_stat(td, uap->path, UIO_USERSPACE, &sb);
2372 	if (error != 0)
2373 		return (error);
2374 	cvtnstat(&sb, &nsb);
2375 	return (copyout(&nsb, uap->ub, sizeof (nsb)));
2376 }
2377 
2378 /*
2379  * NetBSD lstat.  Get file status; this version does not follow links.
2380  */
2381 #ifndef _SYS_SYSPROTO_H_
2382 struct lstat_args {
2383 	char	*path;
2384 	struct stat *ub;
2385 };
2386 #endif
2387 int
2388 sys_nlstat(td, uap)
2389 	struct thread *td;
2390 	register struct nlstat_args /* {
2391 		char *path;
2392 		struct nstat *ub;
2393 	} */ *uap;
2394 {
2395 	struct stat sb;
2396 	struct nstat nsb;
2397 	int error;
2398 
2399 	error = kern_lstat(td, uap->path, UIO_USERSPACE, &sb);
2400 	if (error != 0)
2401 		return (error);
2402 	cvtnstat(&sb, &nsb);
2403 	return (copyout(&nsb, uap->ub, sizeof (nsb)));
2404 }
2405 
2406 /*
2407  * Get configurable pathname variables.
2408  */
2409 #ifndef _SYS_SYSPROTO_H_
2410 struct pathconf_args {
2411 	char	*path;
2412 	int	name;
2413 };
2414 #endif
2415 int
2416 sys_pathconf(td, uap)
2417 	struct thread *td;
2418 	register struct pathconf_args /* {
2419 		char *path;
2420 		int name;
2421 	} */ *uap;
2422 {
2423 
2424 	return (kern_pathconf(td, uap->path, UIO_USERSPACE, uap->name, FOLLOW));
2425 }
2426 
2427 #ifndef _SYS_SYSPROTO_H_
2428 struct lpathconf_args {
2429 	char	*path;
2430 	int	name;
2431 };
2432 #endif
2433 int
2434 sys_lpathconf(td, uap)
2435 	struct thread *td;
2436 	register struct lpathconf_args /* {
2437 		char *path;
2438 		int name;
2439 	} */ *uap;
2440 {
2441 
2442 	return (kern_pathconf(td, uap->path, UIO_USERSPACE, uap->name,
2443 	    NOFOLLOW));
2444 }
2445 
2446 int
2447 kern_pathconf(struct thread *td, char *path, enum uio_seg pathseg, int name,
2448     u_long flags)
2449 {
2450 	struct nameidata nd;
2451 	int error;
2452 
2453 	NDINIT(&nd, LOOKUP, LOCKSHARED | LOCKLEAF | AUDITVNODE1 | flags,
2454 	    pathseg, path, td);
2455 	if ((error = namei(&nd)) != 0)
2456 		return (error);
2457 	NDFREE(&nd, NDF_ONLY_PNBUF);
2458 
2459 	/* If asynchronous I/O is available, it works for all files. */
2460 	if (name == _PC_ASYNC_IO)
2461 		td->td_retval[0] = async_io_version;
2462 	else
2463 		error = VOP_PATHCONF(nd.ni_vp, name, td->td_retval);
2464 	vput(nd.ni_vp);
2465 	return (error);
2466 }
2467 
2468 /*
2469  * Return target name of a symbolic link.
2470  */
2471 #ifndef _SYS_SYSPROTO_H_
2472 struct readlink_args {
2473 	char	*path;
2474 	char	*buf;
2475 	size_t	count;
2476 };
2477 #endif
2478 int
2479 sys_readlink(td, uap)
2480 	struct thread *td;
2481 	register struct readlink_args /* {
2482 		char *path;
2483 		char *buf;
2484 		size_t count;
2485 	} */ *uap;
2486 {
2487 
2488 	return (kern_readlink(td, uap->path, UIO_USERSPACE, uap->buf,
2489 	    UIO_USERSPACE, uap->count));
2490 }
2491 #ifndef _SYS_SYSPROTO_H_
2492 struct readlinkat_args {
2493 	int	fd;
2494 	char	*path;
2495 	char	*buf;
2496 	size_t	bufsize;
2497 };
2498 #endif
2499 int
2500 sys_readlinkat(struct thread *td, struct readlinkat_args *uap)
2501 {
2502 
2503 	return (kern_readlinkat(td, uap->fd, uap->path, UIO_USERSPACE,
2504 	    uap->buf, UIO_USERSPACE, uap->bufsize));
2505 }
2506 
2507 int
2508 kern_readlink(struct thread *td, char *path, enum uio_seg pathseg, char *buf,
2509     enum uio_seg bufseg, size_t count)
2510 {
2511 
2512 	return (kern_readlinkat(td, AT_FDCWD, path, pathseg, buf, bufseg,
2513 	    count));
2514 }
2515 
2516 int
2517 kern_readlinkat(struct thread *td, int fd, char *path, enum uio_seg pathseg,
2518     char *buf, enum uio_seg bufseg, size_t count)
2519 {
2520 	struct vnode *vp;
2521 	struct iovec aiov;
2522 	struct uio auio;
2523 	struct nameidata nd;
2524 	int error;
2525 
2526 	if (count > IOSIZE_MAX)
2527 		return (EINVAL);
2528 
2529 	NDINIT_AT(&nd, LOOKUP, NOFOLLOW | LOCKSHARED | LOCKLEAF | AUDITVNODE1,
2530 	    pathseg, path, fd, td);
2531 
2532 	if ((error = namei(&nd)) != 0)
2533 		return (error);
2534 	NDFREE(&nd, NDF_ONLY_PNBUF);
2535 	vp = nd.ni_vp;
2536 #ifdef MAC
2537 	error = mac_vnode_check_readlink(td->td_ucred, vp);
2538 	if (error != 0) {
2539 		vput(vp);
2540 		return (error);
2541 	}
2542 #endif
2543 	if (vp->v_type != VLNK)
2544 		error = EINVAL;
2545 	else {
2546 		aiov.iov_base = buf;
2547 		aiov.iov_len = count;
2548 		auio.uio_iov = &aiov;
2549 		auio.uio_iovcnt = 1;
2550 		auio.uio_offset = 0;
2551 		auio.uio_rw = UIO_READ;
2552 		auio.uio_segflg = bufseg;
2553 		auio.uio_td = td;
2554 		auio.uio_resid = count;
2555 		error = VOP_READLINK(vp, &auio, td->td_ucred);
2556 	}
2557 	vput(vp);
2558 	td->td_retval[0] = count - auio.uio_resid;
2559 	return (error);
2560 }
2561 
2562 /*
2563  * Common implementation code for chflags() and fchflags().
2564  */
2565 static int
2566 setfflags(td, vp, flags)
2567 	struct thread *td;
2568 	struct vnode *vp;
2569 	u_long flags;
2570 {
2571 	struct mount *mp;
2572 	struct vattr vattr;
2573 	int error;
2574 
2575 	/* We can't support the value matching VNOVAL. */
2576 	if (flags == VNOVAL)
2577 		return (EOPNOTSUPP);
2578 
2579 	/*
2580 	 * Prevent non-root users from setting flags on devices.  When
2581 	 * a device is reused, users can retain ownership of the device
2582 	 * if they are allowed to set flags and programs assume that
2583 	 * chown can't fail when done as root.
2584 	 */
2585 	if (vp->v_type == VCHR || vp->v_type == VBLK) {
2586 		error = priv_check(td, PRIV_VFS_CHFLAGS_DEV);
2587 		if (error != 0)
2588 			return (error);
2589 	}
2590 
2591 	if ((error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0)
2592 		return (error);
2593 	VATTR_NULL(&vattr);
2594 	vattr.va_flags = flags;
2595 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
2596 #ifdef MAC
2597 	error = mac_vnode_check_setflags(td->td_ucred, vp, vattr.va_flags);
2598 	if (error == 0)
2599 #endif
2600 		error = VOP_SETATTR(vp, &vattr, td->td_ucred);
2601 	VOP_UNLOCK(vp, 0);
2602 	vn_finished_write(mp);
2603 	return (error);
2604 }
2605 
2606 /*
2607  * Change flags of a file given a path name.
2608  */
2609 #ifndef _SYS_SYSPROTO_H_
2610 struct chflags_args {
2611 	const char *path;
2612 	u_long	flags;
2613 };
2614 #endif
2615 int
2616 sys_chflags(td, uap)
2617 	struct thread *td;
2618 	register struct chflags_args /* {
2619 		const char *path;
2620 		u_long flags;
2621 	} */ *uap;
2622 {
2623 
2624 	return (kern_chflags(td, uap->path, UIO_USERSPACE, uap->flags));
2625 }
2626 
2627 #ifndef _SYS_SYSPROTO_H_
2628 struct chflagsat_args {
2629 	int	fd;
2630 	const char *path;
2631 	u_long	flags;
2632 	int	atflag;
2633 }
2634 #endif
2635 int
2636 sys_chflagsat(struct thread *td, struct chflagsat_args *uap)
2637 {
2638 	int fd = uap->fd;
2639 	const char *path = uap->path;
2640 	u_long flags = uap->flags;
2641 	int atflag = uap->atflag;
2642 
2643 	if (atflag & ~AT_SYMLINK_NOFOLLOW)
2644 		return (EINVAL);
2645 
2646 	return (kern_chflagsat(td, fd, path, UIO_USERSPACE, flags, atflag));
2647 }
2648 
2649 static int
2650 kern_chflags(struct thread *td, const char *path, enum uio_seg pathseg,
2651     u_long flags)
2652 {
2653 
2654 	return (kern_chflagsat(td, AT_FDCWD, path, pathseg, flags, 0));
2655 }
2656 
2657 /*
2658  * Same as chflags() but doesn't follow symlinks.
2659  */
2660 int
2661 sys_lchflags(td, uap)
2662 	struct thread *td;
2663 	register struct lchflags_args /* {
2664 		const char *path;
2665 		u_long flags;
2666 	} */ *uap;
2667 {
2668 
2669 	return (kern_chflagsat(td, AT_FDCWD, uap->path, UIO_USERSPACE,
2670 	    uap->flags, AT_SYMLINK_NOFOLLOW));
2671 }
2672 
2673 static int
2674 kern_chflagsat(struct thread *td, int fd, const char *path,
2675     enum uio_seg pathseg, u_long flags, int atflag)
2676 {
2677 	struct nameidata nd;
2678 	cap_rights_t rights;
2679 	int error, follow;
2680 
2681 	AUDIT_ARG_FFLAGS(flags);
2682 	follow = (atflag & AT_SYMLINK_NOFOLLOW) ? NOFOLLOW : FOLLOW;
2683 	NDINIT_ATRIGHTS(&nd, LOOKUP, follow | AUDITVNODE1, pathseg, path, fd,
2684 	    cap_rights_init(&rights, CAP_FCHFLAGS), td);
2685 	if ((error = namei(&nd)) != 0)
2686 		return (error);
2687 	NDFREE(&nd, NDF_ONLY_PNBUF);
2688 	error = setfflags(td, nd.ni_vp, flags);
2689 	vrele(nd.ni_vp);
2690 	return (error);
2691 }
2692 
2693 /*
2694  * Change flags of a file given a file descriptor.
2695  */
2696 #ifndef _SYS_SYSPROTO_H_
2697 struct fchflags_args {
2698 	int	fd;
2699 	u_long	flags;
2700 };
2701 #endif
2702 int
2703 sys_fchflags(td, uap)
2704 	struct thread *td;
2705 	register struct fchflags_args /* {
2706 		int fd;
2707 		u_long flags;
2708 	} */ *uap;
2709 {
2710 	struct file *fp;
2711 	cap_rights_t rights;
2712 	int error;
2713 
2714 	AUDIT_ARG_FD(uap->fd);
2715 	AUDIT_ARG_FFLAGS(uap->flags);
2716 	error = getvnode(td->td_proc->p_fd, uap->fd,
2717 	    cap_rights_init(&rights, CAP_FCHFLAGS), &fp);
2718 	if (error != 0)
2719 		return (error);
2720 #ifdef AUDIT
2721 	vn_lock(fp->f_vnode, LK_SHARED | LK_RETRY);
2722 	AUDIT_ARG_VNODE1(fp->f_vnode);
2723 	VOP_UNLOCK(fp->f_vnode, 0);
2724 #endif
2725 	error = setfflags(td, fp->f_vnode, uap->flags);
2726 	fdrop(fp, td);
2727 	return (error);
2728 }
2729 
2730 /*
2731  * Common implementation code for chmod(), lchmod() and fchmod().
2732  */
2733 int
2734 setfmode(td, cred, vp, mode)
2735 	struct thread *td;
2736 	struct ucred *cred;
2737 	struct vnode *vp;
2738 	int mode;
2739 {
2740 	struct mount *mp;
2741 	struct vattr vattr;
2742 	int error;
2743 
2744 	if ((error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0)
2745 		return (error);
2746 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
2747 	VATTR_NULL(&vattr);
2748 	vattr.va_mode = mode & ALLPERMS;
2749 #ifdef MAC
2750 	error = mac_vnode_check_setmode(cred, vp, vattr.va_mode);
2751 	if (error == 0)
2752 #endif
2753 		error = VOP_SETATTR(vp, &vattr, cred);
2754 	VOP_UNLOCK(vp, 0);
2755 	vn_finished_write(mp);
2756 	return (error);
2757 }
2758 
2759 /*
2760  * Change mode of a file given path name.
2761  */
2762 #ifndef _SYS_SYSPROTO_H_
2763 struct chmod_args {
2764 	char	*path;
2765 	int	mode;
2766 };
2767 #endif
2768 int
2769 sys_chmod(td, uap)
2770 	struct thread *td;
2771 	register struct chmod_args /* {
2772 		char *path;
2773 		int mode;
2774 	} */ *uap;
2775 {
2776 
2777 	return (kern_chmod(td, uap->path, UIO_USERSPACE, uap->mode));
2778 }
2779 
2780 #ifndef _SYS_SYSPROTO_H_
2781 struct fchmodat_args {
2782 	int	dirfd;
2783 	char	*path;
2784 	mode_t	mode;
2785 	int	flag;
2786 }
2787 #endif
2788 int
2789 sys_fchmodat(struct thread *td, struct fchmodat_args *uap)
2790 {
2791 	int flag = uap->flag;
2792 	int fd = uap->fd;
2793 	char *path = uap->path;
2794 	mode_t mode = uap->mode;
2795 
2796 	if (flag & ~AT_SYMLINK_NOFOLLOW)
2797 		return (EINVAL);
2798 
2799 	return (kern_fchmodat(td, fd, path, UIO_USERSPACE, mode, flag));
2800 }
2801 
2802 int
2803 kern_chmod(struct thread *td, char *path, enum uio_seg pathseg, int mode)
2804 {
2805 
2806 	return (kern_fchmodat(td, AT_FDCWD, path, pathseg, mode, 0));
2807 }
2808 
2809 /*
2810  * Change mode of a file given path name (don't follow links.)
2811  */
2812 #ifndef _SYS_SYSPROTO_H_
2813 struct lchmod_args {
2814 	char	*path;
2815 	int	mode;
2816 };
2817 #endif
2818 int
2819 sys_lchmod(td, uap)
2820 	struct thread *td;
2821 	register struct lchmod_args /* {
2822 		char *path;
2823 		int mode;
2824 	} */ *uap;
2825 {
2826 
2827 	return (kern_fchmodat(td, AT_FDCWD, uap->path, UIO_USERSPACE,
2828 	    uap->mode, AT_SYMLINK_NOFOLLOW));
2829 }
2830 
2831 int
2832 kern_fchmodat(struct thread *td, int fd, char *path, enum uio_seg pathseg,
2833     mode_t mode, int flag)
2834 {
2835 	struct nameidata nd;
2836 	cap_rights_t rights;
2837 	int error, follow;
2838 
2839 	AUDIT_ARG_MODE(mode);
2840 	follow = (flag & AT_SYMLINK_NOFOLLOW) ? NOFOLLOW : FOLLOW;
2841 	NDINIT_ATRIGHTS(&nd, LOOKUP, follow | AUDITVNODE1, pathseg, path, fd,
2842 	    cap_rights_init(&rights, CAP_FCHMOD), td);
2843 	if ((error = namei(&nd)) != 0)
2844 		return (error);
2845 	NDFREE(&nd, NDF_ONLY_PNBUF);
2846 	error = setfmode(td, td->td_ucred, nd.ni_vp, mode);
2847 	vrele(nd.ni_vp);
2848 	return (error);
2849 }
2850 
2851 /*
2852  * Change mode of a file given a file descriptor.
2853  */
2854 #ifndef _SYS_SYSPROTO_H_
2855 struct fchmod_args {
2856 	int	fd;
2857 	int	mode;
2858 };
2859 #endif
2860 int
2861 sys_fchmod(struct thread *td, struct fchmod_args *uap)
2862 {
2863 	struct file *fp;
2864 	cap_rights_t rights;
2865 	int error;
2866 
2867 	AUDIT_ARG_FD(uap->fd);
2868 	AUDIT_ARG_MODE(uap->mode);
2869 
2870 	error = fget(td, uap->fd, cap_rights_init(&rights, CAP_FCHMOD), &fp);
2871 	if (error != 0)
2872 		return (error);
2873 	error = fo_chmod(fp, uap->mode, td->td_ucred, td);
2874 	fdrop(fp, td);
2875 	return (error);
2876 }
2877 
2878 /*
2879  * Common implementation for chown(), lchown(), and fchown()
2880  */
2881 int
2882 setfown(td, cred, vp, uid, gid)
2883 	struct thread *td;
2884 	struct ucred *cred;
2885 	struct vnode *vp;
2886 	uid_t uid;
2887 	gid_t gid;
2888 {
2889 	struct mount *mp;
2890 	struct vattr vattr;
2891 	int error;
2892 
2893 	if ((error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0)
2894 		return (error);
2895 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
2896 	VATTR_NULL(&vattr);
2897 	vattr.va_uid = uid;
2898 	vattr.va_gid = gid;
2899 #ifdef MAC
2900 	error = mac_vnode_check_setowner(cred, vp, vattr.va_uid,
2901 	    vattr.va_gid);
2902 	if (error == 0)
2903 #endif
2904 		error = VOP_SETATTR(vp, &vattr, cred);
2905 	VOP_UNLOCK(vp, 0);
2906 	vn_finished_write(mp);
2907 	return (error);
2908 }
2909 
2910 /*
2911  * Set ownership given a path name.
2912  */
2913 #ifndef _SYS_SYSPROTO_H_
2914 struct chown_args {
2915 	char	*path;
2916 	int	uid;
2917 	int	gid;
2918 };
2919 #endif
2920 int
2921 sys_chown(td, uap)
2922 	struct thread *td;
2923 	register struct chown_args /* {
2924 		char *path;
2925 		int uid;
2926 		int gid;
2927 	} */ *uap;
2928 {
2929 
2930 	return (kern_chown(td, uap->path, UIO_USERSPACE, uap->uid, uap->gid));
2931 }
2932 
2933 #ifndef _SYS_SYSPROTO_H_
2934 struct fchownat_args {
2935 	int fd;
2936 	const char * path;
2937 	uid_t uid;
2938 	gid_t gid;
2939 	int flag;
2940 };
2941 #endif
2942 int
2943 sys_fchownat(struct thread *td, struct fchownat_args *uap)
2944 {
2945 	int flag;
2946 
2947 	flag = uap->flag;
2948 	if (flag & ~AT_SYMLINK_NOFOLLOW)
2949 		return (EINVAL);
2950 
2951 	return (kern_fchownat(td, uap->fd, uap->path, UIO_USERSPACE, uap->uid,
2952 	    uap->gid, uap->flag));
2953 }
2954 
2955 int
2956 kern_chown(struct thread *td, char *path, enum uio_seg pathseg, int uid,
2957     int gid)
2958 {
2959 
2960 	return (kern_fchownat(td, AT_FDCWD, path, pathseg, uid, gid, 0));
2961 }
2962 
2963 int
2964 kern_fchownat(struct thread *td, int fd, char *path, enum uio_seg pathseg,
2965     int uid, int gid, int flag)
2966 {
2967 	struct nameidata nd;
2968 	cap_rights_t rights;
2969 	int error, follow;
2970 
2971 	AUDIT_ARG_OWNER(uid, gid);
2972 	follow = (flag & AT_SYMLINK_NOFOLLOW) ? NOFOLLOW : FOLLOW;
2973 	NDINIT_ATRIGHTS(&nd, LOOKUP, follow | AUDITVNODE1, pathseg, path, fd,
2974 	    cap_rights_init(&rights, CAP_FCHOWN), td);
2975 
2976 	if ((error = namei(&nd)) != 0)
2977 		return (error);
2978 	NDFREE(&nd, NDF_ONLY_PNBUF);
2979 	error = setfown(td, td->td_ucred, nd.ni_vp, uid, gid);
2980 	vrele(nd.ni_vp);
2981 	return (error);
2982 }
2983 
2984 /*
2985  * Set ownership given a path name, do not cross symlinks.
2986  */
2987 #ifndef _SYS_SYSPROTO_H_
2988 struct lchown_args {
2989 	char	*path;
2990 	int	uid;
2991 	int	gid;
2992 };
2993 #endif
2994 int
2995 sys_lchown(td, uap)
2996 	struct thread *td;
2997 	register struct lchown_args /* {
2998 		char *path;
2999 		int uid;
3000 		int gid;
3001 	} */ *uap;
3002 {
3003 
3004 	return (kern_lchown(td, uap->path, UIO_USERSPACE, uap->uid, uap->gid));
3005 }
3006 
3007 int
3008 kern_lchown(struct thread *td, char *path, enum uio_seg pathseg, int uid,
3009     int gid)
3010 {
3011 
3012 	return (kern_fchownat(td, AT_FDCWD, path, pathseg, uid, gid,
3013 	    AT_SYMLINK_NOFOLLOW));
3014 }
3015 
3016 /*
3017  * Set ownership given a file descriptor.
3018  */
3019 #ifndef _SYS_SYSPROTO_H_
3020 struct fchown_args {
3021 	int	fd;
3022 	int	uid;
3023 	int	gid;
3024 };
3025 #endif
3026 int
3027 sys_fchown(td, uap)
3028 	struct thread *td;
3029 	register struct fchown_args /* {
3030 		int fd;
3031 		int uid;
3032 		int gid;
3033 	} */ *uap;
3034 {
3035 	struct file *fp;
3036 	cap_rights_t rights;
3037 	int error;
3038 
3039 	AUDIT_ARG_FD(uap->fd);
3040 	AUDIT_ARG_OWNER(uap->uid, uap->gid);
3041 	error = fget(td, uap->fd, cap_rights_init(&rights, CAP_FCHOWN), &fp);
3042 	if (error != 0)
3043 		return (error);
3044 	error = fo_chown(fp, uap->uid, uap->gid, td->td_ucred, td);
3045 	fdrop(fp, td);
3046 	return (error);
3047 }
3048 
3049 /*
3050  * Common implementation code for utimes(), lutimes(), and futimes().
3051  */
3052 static int
3053 getutimes(usrtvp, tvpseg, tsp)
3054 	const struct timeval *usrtvp;
3055 	enum uio_seg tvpseg;
3056 	struct timespec *tsp;
3057 {
3058 	struct timeval tv[2];
3059 	const struct timeval *tvp;
3060 	int error;
3061 
3062 	if (usrtvp == NULL) {
3063 		vfs_timestamp(&tsp[0]);
3064 		tsp[1] = tsp[0];
3065 	} else {
3066 		if (tvpseg == UIO_SYSSPACE) {
3067 			tvp = usrtvp;
3068 		} else {
3069 			if ((error = copyin(usrtvp, tv, sizeof(tv))) != 0)
3070 				return (error);
3071 			tvp = tv;
3072 		}
3073 
3074 		if (tvp[0].tv_usec < 0 || tvp[0].tv_usec >= 1000000 ||
3075 		    tvp[1].tv_usec < 0 || tvp[1].tv_usec >= 1000000)
3076 			return (EINVAL);
3077 		TIMEVAL_TO_TIMESPEC(&tvp[0], &tsp[0]);
3078 		TIMEVAL_TO_TIMESPEC(&tvp[1], &tsp[1]);
3079 	}
3080 	return (0);
3081 }
3082 
3083 /*
3084  * Common implementation code for utimes(), lutimes(), and futimes().
3085  */
3086 static int
3087 setutimes(td, vp, ts, numtimes, nullflag)
3088 	struct thread *td;
3089 	struct vnode *vp;
3090 	const struct timespec *ts;
3091 	int numtimes;
3092 	int nullflag;
3093 {
3094 	struct mount *mp;
3095 	struct vattr vattr;
3096 	int error, setbirthtime;
3097 
3098 	if ((error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0)
3099 		return (error);
3100 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3101 	setbirthtime = 0;
3102 	if (numtimes < 3 && !VOP_GETATTR(vp, &vattr, td->td_ucred) &&
3103 	    timespeccmp(&ts[1], &vattr.va_birthtime, < ))
3104 		setbirthtime = 1;
3105 	VATTR_NULL(&vattr);
3106 	vattr.va_atime = ts[0];
3107 	vattr.va_mtime = ts[1];
3108 	if (setbirthtime)
3109 		vattr.va_birthtime = ts[1];
3110 	if (numtimes > 2)
3111 		vattr.va_birthtime = ts[2];
3112 	if (nullflag)
3113 		vattr.va_vaflags |= VA_UTIMES_NULL;
3114 #ifdef MAC
3115 	error = mac_vnode_check_setutimes(td->td_ucred, vp, vattr.va_atime,
3116 	    vattr.va_mtime);
3117 #endif
3118 	if (error == 0)
3119 		error = VOP_SETATTR(vp, &vattr, td->td_ucred);
3120 	VOP_UNLOCK(vp, 0);
3121 	vn_finished_write(mp);
3122 	return (error);
3123 }
3124 
3125 /*
3126  * Set the access and modification times of a file.
3127  */
3128 #ifndef _SYS_SYSPROTO_H_
3129 struct utimes_args {
3130 	char	*path;
3131 	struct	timeval *tptr;
3132 };
3133 #endif
3134 int
3135 sys_utimes(td, uap)
3136 	struct thread *td;
3137 	register struct utimes_args /* {
3138 		char *path;
3139 		struct timeval *tptr;
3140 	} */ *uap;
3141 {
3142 
3143 	return (kern_utimes(td, uap->path, UIO_USERSPACE, uap->tptr,
3144 	    UIO_USERSPACE));
3145 }
3146 
3147 #ifndef _SYS_SYSPROTO_H_
3148 struct futimesat_args {
3149 	int fd;
3150 	const char * path;
3151 	const struct timeval * times;
3152 };
3153 #endif
3154 int
3155 sys_futimesat(struct thread *td, struct futimesat_args *uap)
3156 {
3157 
3158 	return (kern_utimesat(td, uap->fd, uap->path, UIO_USERSPACE,
3159 	    uap->times, UIO_USERSPACE));
3160 }
3161 
3162 int
3163 kern_utimes(struct thread *td, char *path, enum uio_seg pathseg,
3164     struct timeval *tptr, enum uio_seg tptrseg)
3165 {
3166 
3167 	return (kern_utimesat(td, AT_FDCWD, path, pathseg, tptr, tptrseg));
3168 }
3169 
3170 int
3171 kern_utimesat(struct thread *td, int fd, char *path, enum uio_seg pathseg,
3172     struct timeval *tptr, enum uio_seg tptrseg)
3173 {
3174 	struct nameidata nd;
3175 	struct timespec ts[2];
3176 	cap_rights_t rights;
3177 	int error;
3178 
3179 	if ((error = getutimes(tptr, tptrseg, ts)) != 0)
3180 		return (error);
3181 	NDINIT_ATRIGHTS(&nd, LOOKUP, FOLLOW | AUDITVNODE1, pathseg, path, fd,
3182 	    cap_rights_init(&rights, CAP_FUTIMES), td);
3183 
3184 	if ((error = namei(&nd)) != 0)
3185 		return (error);
3186 	NDFREE(&nd, NDF_ONLY_PNBUF);
3187 	error = setutimes(td, nd.ni_vp, ts, 2, tptr == NULL);
3188 	vrele(nd.ni_vp);
3189 	return (error);
3190 }
3191 
3192 /*
3193  * Set the access and modification times of a file.
3194  */
3195 #ifndef _SYS_SYSPROTO_H_
3196 struct lutimes_args {
3197 	char	*path;
3198 	struct	timeval *tptr;
3199 };
3200 #endif
3201 int
3202 sys_lutimes(td, uap)
3203 	struct thread *td;
3204 	register struct lutimes_args /* {
3205 		char *path;
3206 		struct timeval *tptr;
3207 	} */ *uap;
3208 {
3209 
3210 	return (kern_lutimes(td, uap->path, UIO_USERSPACE, uap->tptr,
3211 	    UIO_USERSPACE));
3212 }
3213 
3214 int
3215 kern_lutimes(struct thread *td, char *path, enum uio_seg pathseg,
3216     struct timeval *tptr, enum uio_seg tptrseg)
3217 {
3218 	struct timespec ts[2];
3219 	struct nameidata nd;
3220 	int error;
3221 
3222 	if ((error = getutimes(tptr, tptrseg, ts)) != 0)
3223 		return (error);
3224 	NDINIT(&nd, LOOKUP, NOFOLLOW | AUDITVNODE1, pathseg, path, td);
3225 	if ((error = namei(&nd)) != 0)
3226 		return (error);
3227 	NDFREE(&nd, NDF_ONLY_PNBUF);
3228 	error = setutimes(td, nd.ni_vp, ts, 2, tptr == NULL);
3229 	vrele(nd.ni_vp);
3230 	return (error);
3231 }
3232 
3233 /*
3234  * Set the access and modification times of a file.
3235  */
3236 #ifndef _SYS_SYSPROTO_H_
3237 struct futimes_args {
3238 	int	fd;
3239 	struct	timeval *tptr;
3240 };
3241 #endif
3242 int
3243 sys_futimes(td, uap)
3244 	struct thread *td;
3245 	register struct futimes_args /* {
3246 		int  fd;
3247 		struct timeval *tptr;
3248 	} */ *uap;
3249 {
3250 
3251 	return (kern_futimes(td, uap->fd, uap->tptr, UIO_USERSPACE));
3252 }
3253 
3254 int
3255 kern_futimes(struct thread *td, int fd, struct timeval *tptr,
3256     enum uio_seg tptrseg)
3257 {
3258 	struct timespec ts[2];
3259 	struct file *fp;
3260 	cap_rights_t rights;
3261 	int error;
3262 
3263 	AUDIT_ARG_FD(fd);
3264 	error = getutimes(tptr, tptrseg, ts);
3265 	if (error != 0)
3266 		return (error);
3267 	error = getvnode(td->td_proc->p_fd, fd,
3268 	    cap_rights_init(&rights, CAP_FUTIMES), &fp);
3269 	if (error != 0)
3270 		return (error);
3271 #ifdef AUDIT
3272 	vn_lock(fp->f_vnode, LK_SHARED | LK_RETRY);
3273 	AUDIT_ARG_VNODE1(fp->f_vnode);
3274 	VOP_UNLOCK(fp->f_vnode, 0);
3275 #endif
3276 	error = setutimes(td, fp->f_vnode, ts, 2, tptr == NULL);
3277 	fdrop(fp, td);
3278 	return (error);
3279 }
3280 
3281 /*
3282  * Truncate a file given its path name.
3283  */
3284 #ifndef _SYS_SYSPROTO_H_
3285 struct truncate_args {
3286 	char	*path;
3287 	int	pad;
3288 	off_t	length;
3289 };
3290 #endif
3291 int
3292 sys_truncate(td, uap)
3293 	struct thread *td;
3294 	register struct truncate_args /* {
3295 		char *path;
3296 		int pad;
3297 		off_t length;
3298 	} */ *uap;
3299 {
3300 
3301 	return (kern_truncate(td, uap->path, UIO_USERSPACE, uap->length));
3302 }
3303 
3304 int
3305 kern_truncate(struct thread *td, char *path, enum uio_seg pathseg, off_t length)
3306 {
3307 	struct mount *mp;
3308 	struct vnode *vp;
3309 	void *rl_cookie;
3310 	struct vattr vattr;
3311 	struct nameidata nd;
3312 	int error;
3313 
3314 	if (length < 0)
3315 		return(EINVAL);
3316 	NDINIT(&nd, LOOKUP, FOLLOW | AUDITVNODE1, pathseg, path, td);
3317 	if ((error = namei(&nd)) != 0)
3318 		return (error);
3319 	vp = nd.ni_vp;
3320 	rl_cookie = vn_rangelock_wlock(vp, 0, OFF_MAX);
3321 	if ((error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0) {
3322 		vn_rangelock_unlock(vp, rl_cookie);
3323 		vrele(vp);
3324 		return (error);
3325 	}
3326 	NDFREE(&nd, NDF_ONLY_PNBUF);
3327 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3328 	if (vp->v_type == VDIR)
3329 		error = EISDIR;
3330 #ifdef MAC
3331 	else if ((error = mac_vnode_check_write(td->td_ucred, NOCRED, vp))) {
3332 	}
3333 #endif
3334 	else if ((error = vn_writechk(vp)) == 0 &&
3335 	    (error = VOP_ACCESS(vp, VWRITE, td->td_ucred, td)) == 0) {
3336 		VATTR_NULL(&vattr);
3337 		vattr.va_size = length;
3338 		error = VOP_SETATTR(vp, &vattr, td->td_ucred);
3339 	}
3340 	VOP_UNLOCK(vp, 0);
3341 	vn_finished_write(mp);
3342 	vn_rangelock_unlock(vp, rl_cookie);
3343 	vrele(vp);
3344 	return (error);
3345 }
3346 
3347 #if defined(COMPAT_43)
3348 /*
3349  * Truncate a file given its path name.
3350  */
3351 #ifndef _SYS_SYSPROTO_H_
3352 struct otruncate_args {
3353 	char	*path;
3354 	long	length;
3355 };
3356 #endif
3357 int
3358 otruncate(td, uap)
3359 	struct thread *td;
3360 	register struct otruncate_args /* {
3361 		char *path;
3362 		long length;
3363 	} */ *uap;
3364 {
3365 	struct truncate_args /* {
3366 		char *path;
3367 		int pad;
3368 		off_t length;
3369 	} */ nuap;
3370 
3371 	nuap.path = uap->path;
3372 	nuap.length = uap->length;
3373 	return (sys_truncate(td, &nuap));
3374 }
3375 #endif /* COMPAT_43 */
3376 
3377 /* Versions with the pad argument */
3378 int
3379 freebsd6_truncate(struct thread *td, struct freebsd6_truncate_args *uap)
3380 {
3381 	struct truncate_args ouap;
3382 
3383 	ouap.path = uap->path;
3384 	ouap.length = uap->length;
3385 	return (sys_truncate(td, &ouap));
3386 }
3387 
3388 int
3389 freebsd6_ftruncate(struct thread *td, struct freebsd6_ftruncate_args *uap)
3390 {
3391 	struct ftruncate_args ouap;
3392 
3393 	ouap.fd = uap->fd;
3394 	ouap.length = uap->length;
3395 	return (sys_ftruncate(td, &ouap));
3396 }
3397 
3398 /*
3399  * Sync an open file.
3400  */
3401 #ifndef _SYS_SYSPROTO_H_
3402 struct fsync_args {
3403 	int	fd;
3404 };
3405 #endif
3406 int
3407 sys_fsync(td, uap)
3408 	struct thread *td;
3409 	struct fsync_args /* {
3410 		int fd;
3411 	} */ *uap;
3412 {
3413 	struct vnode *vp;
3414 	struct mount *mp;
3415 	struct file *fp;
3416 	cap_rights_t rights;
3417 	int error, lock_flags;
3418 
3419 	AUDIT_ARG_FD(uap->fd);
3420 	error = getvnode(td->td_proc->p_fd, uap->fd,
3421 	    cap_rights_init(&rights, CAP_FSYNC), &fp);
3422 	if (error != 0)
3423 		return (error);
3424 	vp = fp->f_vnode;
3425 	error = vn_start_write(vp, &mp, V_WAIT | PCATCH);
3426 	if (error != 0)
3427 		goto drop;
3428 	if (MNT_SHARED_WRITES(mp) ||
3429 	    ((mp == NULL) && MNT_SHARED_WRITES(vp->v_mount))) {
3430 		lock_flags = LK_SHARED;
3431 	} else {
3432 		lock_flags = LK_EXCLUSIVE;
3433 	}
3434 	vn_lock(vp, lock_flags | LK_RETRY);
3435 	AUDIT_ARG_VNODE1(vp);
3436 	if (vp->v_object != NULL) {
3437 		VM_OBJECT_WLOCK(vp->v_object);
3438 		vm_object_page_clean(vp->v_object, 0, 0, 0);
3439 		VM_OBJECT_WUNLOCK(vp->v_object);
3440 	}
3441 	error = VOP_FSYNC(vp, MNT_WAIT, td);
3442 
3443 	VOP_UNLOCK(vp, 0);
3444 	vn_finished_write(mp);
3445 drop:
3446 	fdrop(fp, td);
3447 	return (error);
3448 }
3449 
3450 /*
3451  * Rename files.  Source and destination must either both be directories, or
3452  * both not be directories.  If target is a directory, it must be empty.
3453  */
3454 #ifndef _SYS_SYSPROTO_H_
3455 struct rename_args {
3456 	char	*from;
3457 	char	*to;
3458 };
3459 #endif
3460 int
3461 sys_rename(td, uap)
3462 	struct thread *td;
3463 	register struct rename_args /* {
3464 		char *from;
3465 		char *to;
3466 	} */ *uap;
3467 {
3468 
3469 	return (kern_rename(td, uap->from, uap->to, UIO_USERSPACE));
3470 }
3471 
3472 #ifndef _SYS_SYSPROTO_H_
3473 struct renameat_args {
3474 	int	oldfd;
3475 	char	*old;
3476 	int	newfd;
3477 	char	*new;
3478 };
3479 #endif
3480 int
3481 sys_renameat(struct thread *td, struct renameat_args *uap)
3482 {
3483 
3484 	return (kern_renameat(td, uap->oldfd, uap->old, uap->newfd, uap->new,
3485 	    UIO_USERSPACE));
3486 }
3487 
3488 int
3489 kern_rename(struct thread *td, char *from, char *to, enum uio_seg pathseg)
3490 {
3491 
3492 	return (kern_renameat(td, AT_FDCWD, from, AT_FDCWD, to, pathseg));
3493 }
3494 
3495 int
3496 kern_renameat(struct thread *td, int oldfd, char *old, int newfd, char *new,
3497     enum uio_seg pathseg)
3498 {
3499 	struct mount *mp = NULL;
3500 	struct vnode *tvp, *fvp, *tdvp;
3501 	struct nameidata fromnd, tond;
3502 	cap_rights_t rights;
3503 	int error;
3504 
3505 	bwillwrite();
3506 #ifdef MAC
3507 	NDINIT_ATRIGHTS(&fromnd, DELETE, LOCKPARENT | LOCKLEAF | SAVESTART |
3508 	    AUDITVNODE1, pathseg, old, oldfd,
3509 	    cap_rights_init(&rights, CAP_RENAMEAT), td);
3510 #else
3511 	NDINIT_ATRIGHTS(&fromnd, DELETE, WANTPARENT | SAVESTART | AUDITVNODE1,
3512 	    pathseg, old, oldfd, cap_rights_init(&rights, CAP_RENAMEAT), td);
3513 #endif
3514 
3515 	if ((error = namei(&fromnd)) != 0)
3516 		return (error);
3517 #ifdef MAC
3518 	error = mac_vnode_check_rename_from(td->td_ucred, fromnd.ni_dvp,
3519 	    fromnd.ni_vp, &fromnd.ni_cnd);
3520 	VOP_UNLOCK(fromnd.ni_dvp, 0);
3521 	if (fromnd.ni_dvp != fromnd.ni_vp)
3522 		VOP_UNLOCK(fromnd.ni_vp, 0);
3523 #endif
3524 	fvp = fromnd.ni_vp;
3525 	if (error == 0)
3526 		error = vn_start_write(fvp, &mp, V_WAIT | PCATCH);
3527 	if (error != 0) {
3528 		NDFREE(&fromnd, NDF_ONLY_PNBUF);
3529 		vrele(fromnd.ni_dvp);
3530 		vrele(fvp);
3531 		goto out1;
3532 	}
3533 	NDINIT_ATRIGHTS(&tond, RENAME, LOCKPARENT | LOCKLEAF | NOCACHE |
3534 	    SAVESTART | AUDITVNODE2, pathseg, new, newfd,
3535 	    cap_rights_init(&rights, CAP_LINKAT), td);
3536 	if (fromnd.ni_vp->v_type == VDIR)
3537 		tond.ni_cnd.cn_flags |= WILLBEDIR;
3538 	if ((error = namei(&tond)) != 0) {
3539 		/* Translate error code for rename("dir1", "dir2/."). */
3540 		if (error == EISDIR && fvp->v_type == VDIR)
3541 			error = EINVAL;
3542 		NDFREE(&fromnd, NDF_ONLY_PNBUF);
3543 		vrele(fromnd.ni_dvp);
3544 		vrele(fvp);
3545 		vn_finished_write(mp);
3546 		goto out1;
3547 	}
3548 	tdvp = tond.ni_dvp;
3549 	tvp = tond.ni_vp;
3550 	if (tvp != NULL) {
3551 		if (fvp->v_type == VDIR && tvp->v_type != VDIR) {
3552 			error = ENOTDIR;
3553 			goto out;
3554 		} else if (fvp->v_type != VDIR && tvp->v_type == VDIR) {
3555 			error = EISDIR;
3556 			goto out;
3557 		}
3558 #ifdef CAPABILITIES
3559 		if (newfd != AT_FDCWD) {
3560 			/*
3561 			 * If the target already exists we require CAP_UNLINKAT
3562 			 * from 'newfd'.
3563 			 */
3564 			error = cap_check(&tond.ni_filecaps.fc_rights,
3565 			    cap_rights_init(&rights, CAP_UNLINKAT));
3566 			if (error != 0)
3567 				goto out;
3568 		}
3569 #endif
3570 	}
3571 	if (fvp == tdvp) {
3572 		error = EINVAL;
3573 		goto out;
3574 	}
3575 	/*
3576 	 * If the source is the same as the destination (that is, if they
3577 	 * are links to the same vnode), then there is nothing to do.
3578 	 */
3579 	if (fvp == tvp)
3580 		error = -1;
3581 #ifdef MAC
3582 	else
3583 		error = mac_vnode_check_rename_to(td->td_ucred, tdvp,
3584 		    tond.ni_vp, fromnd.ni_dvp == tdvp, &tond.ni_cnd);
3585 #endif
3586 out:
3587 	if (error == 0) {
3588 		error = VOP_RENAME(fromnd.ni_dvp, fromnd.ni_vp, &fromnd.ni_cnd,
3589 		    tond.ni_dvp, tond.ni_vp, &tond.ni_cnd);
3590 		NDFREE(&fromnd, NDF_ONLY_PNBUF);
3591 		NDFREE(&tond, NDF_ONLY_PNBUF);
3592 	} else {
3593 		NDFREE(&fromnd, NDF_ONLY_PNBUF);
3594 		NDFREE(&tond, NDF_ONLY_PNBUF);
3595 		if (tvp != NULL)
3596 			vput(tvp);
3597 		if (tdvp == tvp)
3598 			vrele(tdvp);
3599 		else
3600 			vput(tdvp);
3601 		vrele(fromnd.ni_dvp);
3602 		vrele(fvp);
3603 	}
3604 	vrele(tond.ni_startdir);
3605 	vn_finished_write(mp);
3606 out1:
3607 	if (fromnd.ni_startdir)
3608 		vrele(fromnd.ni_startdir);
3609 	if (error == -1)
3610 		return (0);
3611 	return (error);
3612 }
3613 
3614 /*
3615  * Make a directory file.
3616  */
3617 #ifndef _SYS_SYSPROTO_H_
3618 struct mkdir_args {
3619 	char	*path;
3620 	int	mode;
3621 };
3622 #endif
3623 int
3624 sys_mkdir(td, uap)
3625 	struct thread *td;
3626 	register struct mkdir_args /* {
3627 		char *path;
3628 		int mode;
3629 	} */ *uap;
3630 {
3631 
3632 	return (kern_mkdir(td, uap->path, UIO_USERSPACE, uap->mode));
3633 }
3634 
3635 #ifndef _SYS_SYSPROTO_H_
3636 struct mkdirat_args {
3637 	int	fd;
3638 	char	*path;
3639 	mode_t	mode;
3640 };
3641 #endif
3642 int
3643 sys_mkdirat(struct thread *td, struct mkdirat_args *uap)
3644 {
3645 
3646 	return (kern_mkdirat(td, uap->fd, uap->path, UIO_USERSPACE, uap->mode));
3647 }
3648 
3649 int
3650 kern_mkdir(struct thread *td, char *path, enum uio_seg segflg, int mode)
3651 {
3652 
3653 	return (kern_mkdirat(td, AT_FDCWD, path, segflg, mode));
3654 }
3655 
3656 int
3657 kern_mkdirat(struct thread *td, int fd, char *path, enum uio_seg segflg,
3658     int mode)
3659 {
3660 	struct mount *mp;
3661 	struct vnode *vp;
3662 	struct vattr vattr;
3663 	struct nameidata nd;
3664 	cap_rights_t rights;
3665 	int error;
3666 
3667 	AUDIT_ARG_MODE(mode);
3668 restart:
3669 	bwillwrite();
3670 	NDINIT_ATRIGHTS(&nd, CREATE, LOCKPARENT | SAVENAME | AUDITVNODE1,
3671 	    segflg, path, fd, cap_rights_init(&rights, CAP_MKDIRAT), td);
3672 	nd.ni_cnd.cn_flags |= WILLBEDIR;
3673 	if ((error = namei(&nd)) != 0)
3674 		return (error);
3675 	vp = nd.ni_vp;
3676 	if (vp != NULL) {
3677 		NDFREE(&nd, NDF_ONLY_PNBUF);
3678 		/*
3679 		 * XXX namei called with LOCKPARENT but not LOCKLEAF has
3680 		 * the strange behaviour of leaving the vnode unlocked
3681 		 * if the target is the same vnode as the parent.
3682 		 */
3683 		if (vp == nd.ni_dvp)
3684 			vrele(nd.ni_dvp);
3685 		else
3686 			vput(nd.ni_dvp);
3687 		vrele(vp);
3688 		return (EEXIST);
3689 	}
3690 	if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
3691 		NDFREE(&nd, NDF_ONLY_PNBUF);
3692 		vput(nd.ni_dvp);
3693 		if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
3694 			return (error);
3695 		goto restart;
3696 	}
3697 	VATTR_NULL(&vattr);
3698 	vattr.va_type = VDIR;
3699 	vattr.va_mode = (mode & ACCESSPERMS) &~ td->td_proc->p_fd->fd_cmask;
3700 #ifdef MAC
3701 	error = mac_vnode_check_create(td->td_ucred, nd.ni_dvp, &nd.ni_cnd,
3702 	    &vattr);
3703 	if (error != 0)
3704 		goto out;
3705 #endif
3706 	error = VOP_MKDIR(nd.ni_dvp, &nd.ni_vp, &nd.ni_cnd, &vattr);
3707 #ifdef MAC
3708 out:
3709 #endif
3710 	NDFREE(&nd, NDF_ONLY_PNBUF);
3711 	vput(nd.ni_dvp);
3712 	if (error == 0)
3713 		vput(nd.ni_vp);
3714 	vn_finished_write(mp);
3715 	return (error);
3716 }
3717 
3718 /*
3719  * Remove a directory file.
3720  */
3721 #ifndef _SYS_SYSPROTO_H_
3722 struct rmdir_args {
3723 	char	*path;
3724 };
3725 #endif
3726 int
3727 sys_rmdir(td, uap)
3728 	struct thread *td;
3729 	struct rmdir_args /* {
3730 		char *path;
3731 	} */ *uap;
3732 {
3733 
3734 	return (kern_rmdir(td, uap->path, UIO_USERSPACE));
3735 }
3736 
3737 int
3738 kern_rmdir(struct thread *td, char *path, enum uio_seg pathseg)
3739 {
3740 
3741 	return (kern_rmdirat(td, AT_FDCWD, path, pathseg));
3742 }
3743 
3744 int
3745 kern_rmdirat(struct thread *td, int fd, char *path, enum uio_seg pathseg)
3746 {
3747 	struct mount *mp;
3748 	struct vnode *vp;
3749 	struct nameidata nd;
3750 	cap_rights_t rights;
3751 	int error;
3752 
3753 restart:
3754 	bwillwrite();
3755 	NDINIT_ATRIGHTS(&nd, DELETE, LOCKPARENT | LOCKLEAF | AUDITVNODE1,
3756 	    pathseg, path, fd, cap_rights_init(&rights, CAP_UNLINKAT), td);
3757 	if ((error = namei(&nd)) != 0)
3758 		return (error);
3759 	vp = nd.ni_vp;
3760 	if (vp->v_type != VDIR) {
3761 		error = ENOTDIR;
3762 		goto out;
3763 	}
3764 	/*
3765 	 * No rmdir "." please.
3766 	 */
3767 	if (nd.ni_dvp == vp) {
3768 		error = EINVAL;
3769 		goto out;
3770 	}
3771 	/*
3772 	 * The root of a mounted filesystem cannot be deleted.
3773 	 */
3774 	if (vp->v_vflag & VV_ROOT) {
3775 		error = EBUSY;
3776 		goto out;
3777 	}
3778 #ifdef MAC
3779 	error = mac_vnode_check_unlink(td->td_ucred, nd.ni_dvp, vp,
3780 	    &nd.ni_cnd);
3781 	if (error != 0)
3782 		goto out;
3783 #endif
3784 	if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
3785 		NDFREE(&nd, NDF_ONLY_PNBUF);
3786 		vput(vp);
3787 		if (nd.ni_dvp == vp)
3788 			vrele(nd.ni_dvp);
3789 		else
3790 			vput(nd.ni_dvp);
3791 		if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
3792 			return (error);
3793 		goto restart;
3794 	}
3795 	vfs_notify_upper(vp, VFS_NOTIFY_UPPER_UNLINK);
3796 	error = VOP_RMDIR(nd.ni_dvp, nd.ni_vp, &nd.ni_cnd);
3797 	vn_finished_write(mp);
3798 out:
3799 	NDFREE(&nd, NDF_ONLY_PNBUF);
3800 	vput(vp);
3801 	if (nd.ni_dvp == vp)
3802 		vrele(nd.ni_dvp);
3803 	else
3804 		vput(nd.ni_dvp);
3805 	return (error);
3806 }
3807 
3808 #ifdef COMPAT_43
3809 /*
3810  * Read a block of directory entries in a filesystem independent format.
3811  */
3812 #ifndef _SYS_SYSPROTO_H_
3813 struct ogetdirentries_args {
3814 	int	fd;
3815 	char	*buf;
3816 	u_int	count;
3817 	long	*basep;
3818 };
3819 #endif
3820 int
3821 ogetdirentries(struct thread *td, struct ogetdirentries_args *uap)
3822 {
3823 	long loff;
3824 	int error;
3825 
3826 	error = kern_ogetdirentries(td, uap, &loff);
3827 	if (error == 0)
3828 		error = copyout(&loff, uap->basep, sizeof(long));
3829 	return (error);
3830 }
3831 
3832 int
3833 kern_ogetdirentries(struct thread *td, struct ogetdirentries_args *uap,
3834     long *ploff)
3835 {
3836 	struct vnode *vp;
3837 	struct file *fp;
3838 	struct uio auio, kuio;
3839 	struct iovec aiov, kiov;
3840 	struct dirent *dp, *edp;
3841 	cap_rights_t rights;
3842 	caddr_t dirbuf;
3843 	int error, eofflag, readcnt;
3844 	long loff;
3845 	off_t foffset;
3846 
3847 	/* XXX arbitrary sanity limit on `count'. */
3848 	if (uap->count > 64 * 1024)
3849 		return (EINVAL);
3850 	error = getvnode(td->td_proc->p_fd, uap->fd,
3851 	    cap_rights_init(&rights, CAP_READ), &fp);
3852 	if (error != 0)
3853 		return (error);
3854 	if ((fp->f_flag & FREAD) == 0) {
3855 		fdrop(fp, td);
3856 		return (EBADF);
3857 	}
3858 	vp = fp->f_vnode;
3859 	foffset = foffset_lock(fp, 0);
3860 unionread:
3861 	if (vp->v_type != VDIR) {
3862 		foffset_unlock(fp, foffset, 0);
3863 		fdrop(fp, td);
3864 		return (EINVAL);
3865 	}
3866 	aiov.iov_base = uap->buf;
3867 	aiov.iov_len = uap->count;
3868 	auio.uio_iov = &aiov;
3869 	auio.uio_iovcnt = 1;
3870 	auio.uio_rw = UIO_READ;
3871 	auio.uio_segflg = UIO_USERSPACE;
3872 	auio.uio_td = td;
3873 	auio.uio_resid = uap->count;
3874 	vn_lock(vp, LK_SHARED | LK_RETRY);
3875 	loff = auio.uio_offset = foffset;
3876 #ifdef MAC
3877 	error = mac_vnode_check_readdir(td->td_ucred, vp);
3878 	if (error != 0) {
3879 		VOP_UNLOCK(vp, 0);
3880 		foffset_unlock(fp, foffset, FOF_NOUPDATE);
3881 		fdrop(fp, td);
3882 		return (error);
3883 	}
3884 #endif
3885 #	if (BYTE_ORDER != LITTLE_ENDIAN)
3886 		if (vp->v_mount->mnt_maxsymlinklen <= 0) {
3887 			error = VOP_READDIR(vp, &auio, fp->f_cred, &eofflag,
3888 			    NULL, NULL);
3889 			foffset = auio.uio_offset;
3890 		} else
3891 #	endif
3892 	{
3893 		kuio = auio;
3894 		kuio.uio_iov = &kiov;
3895 		kuio.uio_segflg = UIO_SYSSPACE;
3896 		kiov.iov_len = uap->count;
3897 		dirbuf = malloc(uap->count, M_TEMP, M_WAITOK);
3898 		kiov.iov_base = dirbuf;
3899 		error = VOP_READDIR(vp, &kuio, fp->f_cred, &eofflag,
3900 			    NULL, NULL);
3901 		foffset = kuio.uio_offset;
3902 		if (error == 0) {
3903 			readcnt = uap->count - kuio.uio_resid;
3904 			edp = (struct dirent *)&dirbuf[readcnt];
3905 			for (dp = (struct dirent *)dirbuf; dp < edp; ) {
3906 #				if (BYTE_ORDER == LITTLE_ENDIAN)
3907 					/*
3908 					 * The expected low byte of
3909 					 * dp->d_namlen is our dp->d_type.
3910 					 * The high MBZ byte of dp->d_namlen
3911 					 * is our dp->d_namlen.
3912 					 */
3913 					dp->d_type = dp->d_namlen;
3914 					dp->d_namlen = 0;
3915 #				else
3916 					/*
3917 					 * The dp->d_type is the high byte
3918 					 * of the expected dp->d_namlen,
3919 					 * so must be zero'ed.
3920 					 */
3921 					dp->d_type = 0;
3922 #				endif
3923 				if (dp->d_reclen > 0) {
3924 					dp = (struct dirent *)
3925 					    ((char *)dp + dp->d_reclen);
3926 				} else {
3927 					error = EIO;
3928 					break;
3929 				}
3930 			}
3931 			if (dp >= edp)
3932 				error = uiomove(dirbuf, readcnt, &auio);
3933 		}
3934 		free(dirbuf, M_TEMP);
3935 	}
3936 	if (error != 0) {
3937 		VOP_UNLOCK(vp, 0);
3938 		foffset_unlock(fp, foffset, 0);
3939 		fdrop(fp, td);
3940 		return (error);
3941 	}
3942 	if (uap->count == auio.uio_resid &&
3943 	    (vp->v_vflag & VV_ROOT) &&
3944 	    (vp->v_mount->mnt_flag & MNT_UNION)) {
3945 		struct vnode *tvp = vp;
3946 		vp = vp->v_mount->mnt_vnodecovered;
3947 		VREF(vp);
3948 		fp->f_vnode = vp;
3949 		fp->f_data = vp;
3950 		foffset = 0;
3951 		vput(tvp);
3952 		goto unionread;
3953 	}
3954 	VOP_UNLOCK(vp, 0);
3955 	foffset_unlock(fp, foffset, 0);
3956 	fdrop(fp, td);
3957 	td->td_retval[0] = uap->count - auio.uio_resid;
3958 	if (error == 0)
3959 		*ploff = loff;
3960 	return (error);
3961 }
3962 #endif /* COMPAT_43 */
3963 
3964 /*
3965  * Read a block of directory entries in a filesystem independent format.
3966  */
3967 #ifndef _SYS_SYSPROTO_H_
3968 struct getdirentries_args {
3969 	int	fd;
3970 	char	*buf;
3971 	u_int	count;
3972 	long	*basep;
3973 };
3974 #endif
3975 int
3976 sys_getdirentries(td, uap)
3977 	struct thread *td;
3978 	register struct getdirentries_args /* {
3979 		int fd;
3980 		char *buf;
3981 		u_int count;
3982 		long *basep;
3983 	} */ *uap;
3984 {
3985 	long base;
3986 	int error;
3987 
3988 	error = kern_getdirentries(td, uap->fd, uap->buf, uap->count, &base,
3989 	    NULL, UIO_USERSPACE);
3990 	if (error != 0)
3991 		return (error);
3992 	if (uap->basep != NULL)
3993 		error = copyout(&base, uap->basep, sizeof(long));
3994 	return (error);
3995 }
3996 
3997 int
3998 kern_getdirentries(struct thread *td, int fd, char *buf, u_int count,
3999     long *basep, ssize_t *residp, enum uio_seg bufseg)
4000 {
4001 	struct vnode *vp;
4002 	struct file *fp;
4003 	struct uio auio;
4004 	struct iovec aiov;
4005 	cap_rights_t rights;
4006 	long loff;
4007 	int error, eofflag;
4008 	off_t foffset;
4009 
4010 	AUDIT_ARG_FD(fd);
4011 	if (count > IOSIZE_MAX)
4012 		return (EINVAL);
4013 	auio.uio_resid = count;
4014 	error = getvnode(td->td_proc->p_fd, fd,
4015 	    cap_rights_init(&rights, CAP_READ), &fp);
4016 	if (error != 0)
4017 		return (error);
4018 	if ((fp->f_flag & FREAD) == 0) {
4019 		fdrop(fp, td);
4020 		return (EBADF);
4021 	}
4022 	vp = fp->f_vnode;
4023 	foffset = foffset_lock(fp, 0);
4024 unionread:
4025 	if (vp->v_type != VDIR) {
4026 		error = EINVAL;
4027 		goto fail;
4028 	}
4029 	aiov.iov_base = buf;
4030 	aiov.iov_len = count;
4031 	auio.uio_iov = &aiov;
4032 	auio.uio_iovcnt = 1;
4033 	auio.uio_rw = UIO_READ;
4034 	auio.uio_segflg = bufseg;
4035 	auio.uio_td = td;
4036 	vn_lock(vp, LK_SHARED | LK_RETRY);
4037 	AUDIT_ARG_VNODE1(vp);
4038 	loff = auio.uio_offset = foffset;
4039 #ifdef MAC
4040 	error = mac_vnode_check_readdir(td->td_ucred, vp);
4041 	if (error == 0)
4042 #endif
4043 		error = VOP_READDIR(vp, &auio, fp->f_cred, &eofflag, NULL,
4044 		    NULL);
4045 	foffset = auio.uio_offset;
4046 	if (error != 0) {
4047 		VOP_UNLOCK(vp, 0);
4048 		goto fail;
4049 	}
4050 	if (count == auio.uio_resid &&
4051 	    (vp->v_vflag & VV_ROOT) &&
4052 	    (vp->v_mount->mnt_flag & MNT_UNION)) {
4053 		struct vnode *tvp = vp;
4054 
4055 		vp = vp->v_mount->mnt_vnodecovered;
4056 		VREF(vp);
4057 		fp->f_vnode = vp;
4058 		fp->f_data = vp;
4059 		foffset = 0;
4060 		vput(tvp);
4061 		goto unionread;
4062 	}
4063 	VOP_UNLOCK(vp, 0);
4064 	*basep = loff;
4065 	if (residp != NULL)
4066 		*residp = auio.uio_resid;
4067 	td->td_retval[0] = count - auio.uio_resid;
4068 fail:
4069 	foffset_unlock(fp, foffset, 0);
4070 	fdrop(fp, td);
4071 	return (error);
4072 }
4073 
4074 #ifndef _SYS_SYSPROTO_H_
4075 struct getdents_args {
4076 	int fd;
4077 	char *buf;
4078 	size_t count;
4079 };
4080 #endif
4081 int
4082 sys_getdents(td, uap)
4083 	struct thread *td;
4084 	register struct getdents_args /* {
4085 		int fd;
4086 		char *buf;
4087 		u_int count;
4088 	} */ *uap;
4089 {
4090 	struct getdirentries_args ap;
4091 
4092 	ap.fd = uap->fd;
4093 	ap.buf = uap->buf;
4094 	ap.count = uap->count;
4095 	ap.basep = NULL;
4096 	return (sys_getdirentries(td, &ap));
4097 }
4098 
4099 /*
4100  * Set the mode mask for creation of filesystem nodes.
4101  */
4102 #ifndef _SYS_SYSPROTO_H_
4103 struct umask_args {
4104 	int	newmask;
4105 };
4106 #endif
4107 int
4108 sys_umask(td, uap)
4109 	struct thread *td;
4110 	struct umask_args /* {
4111 		int newmask;
4112 	} */ *uap;
4113 {
4114 	register struct filedesc *fdp;
4115 
4116 	FILEDESC_XLOCK(td->td_proc->p_fd);
4117 	fdp = td->td_proc->p_fd;
4118 	td->td_retval[0] = fdp->fd_cmask;
4119 	fdp->fd_cmask = uap->newmask & ALLPERMS;
4120 	FILEDESC_XUNLOCK(td->td_proc->p_fd);
4121 	return (0);
4122 }
4123 
4124 /*
4125  * Void all references to file by ripping underlying filesystem away from
4126  * vnode.
4127  */
4128 #ifndef _SYS_SYSPROTO_H_
4129 struct revoke_args {
4130 	char	*path;
4131 };
4132 #endif
4133 int
4134 sys_revoke(td, uap)
4135 	struct thread *td;
4136 	register struct revoke_args /* {
4137 		char *path;
4138 	} */ *uap;
4139 {
4140 	struct vnode *vp;
4141 	struct vattr vattr;
4142 	struct nameidata nd;
4143 	int error;
4144 
4145 	NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | AUDITVNODE1, UIO_USERSPACE,
4146 	    uap->path, td);
4147 	if ((error = namei(&nd)) != 0)
4148 		return (error);
4149 	vp = nd.ni_vp;
4150 	NDFREE(&nd, NDF_ONLY_PNBUF);
4151 	if (vp->v_type != VCHR || vp->v_rdev == NULL) {
4152 		error = EINVAL;
4153 		goto out;
4154 	}
4155 #ifdef MAC
4156 	error = mac_vnode_check_revoke(td->td_ucred, vp);
4157 	if (error != 0)
4158 		goto out;
4159 #endif
4160 	error = VOP_GETATTR(vp, &vattr, td->td_ucred);
4161 	if (error != 0)
4162 		goto out;
4163 	if (td->td_ucred->cr_uid != vattr.va_uid) {
4164 		error = priv_check(td, PRIV_VFS_ADMIN);
4165 		if (error != 0)
4166 			goto out;
4167 	}
4168 	if (vcount(vp) > 1)
4169 		VOP_REVOKE(vp, REVOKEALL);
4170 out:
4171 	vput(vp);
4172 	return (error);
4173 }
4174 
4175 /*
4176  * Convert a user file descriptor to a kernel file entry and check that, if it
4177  * is a capability, the correct rights are present. A reference on the file
4178  * entry is held upon returning.
4179  */
4180 int
4181 getvnode(struct filedesc *fdp, int fd, cap_rights_t *rightsp, struct file **fpp)
4182 {
4183 	struct file *fp;
4184 	int error;
4185 
4186 	error = fget_unlocked(fdp, fd, rightsp, 0, &fp, NULL);
4187 	if (error != 0)
4188 		return (error);
4189 
4190 	/*
4191 	 * The file could be not of the vnode type, or it may be not
4192 	 * yet fully initialized, in which case the f_vnode pointer
4193 	 * may be set, but f_ops is still badfileops.  E.g.,
4194 	 * devfs_open() transiently create such situation to
4195 	 * facilitate csw d_fdopen().
4196 	 *
4197 	 * Dupfdopen() handling in kern_openat() installs the
4198 	 * half-baked file into the process descriptor table, allowing
4199 	 * other thread to dereference it. Guard against the race by
4200 	 * checking f_ops.
4201 	 */
4202 	if (fp->f_vnode == NULL || fp->f_ops == &badfileops) {
4203 		fdrop(fp, curthread);
4204 		return (EINVAL);
4205 	}
4206 	*fpp = fp;
4207 	return (0);
4208 }
4209 
4210 
4211 /*
4212  * Get an (NFS) file handle.
4213  */
4214 #ifndef _SYS_SYSPROTO_H_
4215 struct lgetfh_args {
4216 	char	*fname;
4217 	fhandle_t *fhp;
4218 };
4219 #endif
4220 int
4221 sys_lgetfh(td, uap)
4222 	struct thread *td;
4223 	register struct lgetfh_args *uap;
4224 {
4225 	struct nameidata nd;
4226 	fhandle_t fh;
4227 	register struct vnode *vp;
4228 	int error;
4229 
4230 	error = priv_check(td, PRIV_VFS_GETFH);
4231 	if (error != 0)
4232 		return (error);
4233 	NDINIT(&nd, LOOKUP, NOFOLLOW | LOCKLEAF | AUDITVNODE1, UIO_USERSPACE,
4234 	    uap->fname, td);
4235 	error = namei(&nd);
4236 	if (error != 0)
4237 		return (error);
4238 	NDFREE(&nd, NDF_ONLY_PNBUF);
4239 	vp = nd.ni_vp;
4240 	bzero(&fh, sizeof(fh));
4241 	fh.fh_fsid = vp->v_mount->mnt_stat.f_fsid;
4242 	error = VOP_VPTOFH(vp, &fh.fh_fid);
4243 	vput(vp);
4244 	if (error == 0)
4245 		error = copyout(&fh, uap->fhp, sizeof (fh));
4246 	return (error);
4247 }
4248 
4249 #ifndef _SYS_SYSPROTO_H_
4250 struct getfh_args {
4251 	char	*fname;
4252 	fhandle_t *fhp;
4253 };
4254 #endif
4255 int
4256 sys_getfh(td, uap)
4257 	struct thread *td;
4258 	register struct getfh_args *uap;
4259 {
4260 	struct nameidata nd;
4261 	fhandle_t fh;
4262 	register struct vnode *vp;
4263 	int error;
4264 
4265 	error = priv_check(td, PRIV_VFS_GETFH);
4266 	if (error != 0)
4267 		return (error);
4268 	NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | AUDITVNODE1, UIO_USERSPACE,
4269 	    uap->fname, td);
4270 	error = namei(&nd);
4271 	if (error != 0)
4272 		return (error);
4273 	NDFREE(&nd, NDF_ONLY_PNBUF);
4274 	vp = nd.ni_vp;
4275 	bzero(&fh, sizeof(fh));
4276 	fh.fh_fsid = vp->v_mount->mnt_stat.f_fsid;
4277 	error = VOP_VPTOFH(vp, &fh.fh_fid);
4278 	vput(vp);
4279 	if (error == 0)
4280 		error = copyout(&fh, uap->fhp, sizeof (fh));
4281 	return (error);
4282 }
4283 
4284 /*
4285  * syscall for the rpc.lockd to use to translate a NFS file handle into an
4286  * open descriptor.
4287  *
4288  * warning: do not remove the priv_check() call or this becomes one giant
4289  * security hole.
4290  */
4291 #ifndef _SYS_SYSPROTO_H_
4292 struct fhopen_args {
4293 	const struct fhandle *u_fhp;
4294 	int flags;
4295 };
4296 #endif
4297 int
4298 sys_fhopen(td, uap)
4299 	struct thread *td;
4300 	struct fhopen_args /* {
4301 		const struct fhandle *u_fhp;
4302 		int flags;
4303 	} */ *uap;
4304 {
4305 	struct mount *mp;
4306 	struct vnode *vp;
4307 	struct fhandle fhp;
4308 	struct file *fp;
4309 	int fmode, error;
4310 	int indx;
4311 
4312 	error = priv_check(td, PRIV_VFS_FHOPEN);
4313 	if (error != 0)
4314 		return (error);
4315 	indx = -1;
4316 	fmode = FFLAGS(uap->flags);
4317 	/* why not allow a non-read/write open for our lockd? */
4318 	if (((fmode & (FREAD | FWRITE)) == 0) || (fmode & O_CREAT))
4319 		return (EINVAL);
4320 	error = copyin(uap->u_fhp, &fhp, sizeof(fhp));
4321 	if (error != 0)
4322 		return(error);
4323 	/* find the mount point */
4324 	mp = vfs_busyfs(&fhp.fh_fsid);
4325 	if (mp == NULL)
4326 		return (ESTALE);
4327 	/* now give me my vnode, it gets returned to me locked */
4328 	error = VFS_FHTOVP(mp, &fhp.fh_fid, LK_EXCLUSIVE, &vp);
4329 	vfs_unbusy(mp);
4330 	if (error != 0)
4331 		return (error);
4332 
4333 	error = falloc_noinstall(td, &fp);
4334 	if (error != 0) {
4335 		vput(vp);
4336 		return (error);
4337 	}
4338 	/*
4339 	 * An extra reference on `fp' has been held for us by
4340 	 * falloc_noinstall().
4341 	 */
4342 
4343 #ifdef INVARIANTS
4344 	td->td_dupfd = -1;
4345 #endif
4346 	error = vn_open_vnode(vp, fmode, td->td_ucred, td, fp);
4347 	if (error != 0) {
4348 		KASSERT(fp->f_ops == &badfileops,
4349 		    ("VOP_OPEN in fhopen() set f_ops"));
4350 		KASSERT(td->td_dupfd < 0,
4351 		    ("fhopen() encountered fdopen()"));
4352 
4353 		vput(vp);
4354 		goto bad;
4355 	}
4356 #ifdef INVARIANTS
4357 	td->td_dupfd = 0;
4358 #endif
4359 	fp->f_vnode = vp;
4360 	fp->f_seqcount = 1;
4361 	finit(fp, (fmode & FMASK) | (fp->f_flag & FHASLOCK), DTYPE_VNODE, vp,
4362 	    &vnops);
4363 	VOP_UNLOCK(vp, 0);
4364 	if ((fmode & O_TRUNC) != 0) {
4365 		error = fo_truncate(fp, 0, td->td_ucred, td);
4366 		if (error != 0)
4367 			goto bad;
4368 	}
4369 
4370 	error = finstall(td, fp, &indx, fmode, NULL);
4371 bad:
4372 	fdrop(fp, td);
4373 	td->td_retval[0] = indx;
4374 	return (error);
4375 }
4376 
4377 /*
4378  * Stat an (NFS) file handle.
4379  */
4380 #ifndef _SYS_SYSPROTO_H_
4381 struct fhstat_args {
4382 	struct fhandle *u_fhp;
4383 	struct stat *sb;
4384 };
4385 #endif
4386 int
4387 sys_fhstat(td, uap)
4388 	struct thread *td;
4389 	register struct fhstat_args /* {
4390 		struct fhandle *u_fhp;
4391 		struct stat *sb;
4392 	} */ *uap;
4393 {
4394 	struct stat sb;
4395 	struct fhandle fh;
4396 	int error;
4397 
4398 	error = copyin(uap->u_fhp, &fh, sizeof(fh));
4399 	if (error != 0)
4400 		return (error);
4401 	error = kern_fhstat(td, fh, &sb);
4402 	if (error == 0)
4403 		error = copyout(&sb, uap->sb, sizeof(sb));
4404 	return (error);
4405 }
4406 
4407 int
4408 kern_fhstat(struct thread *td, struct fhandle fh, struct stat *sb)
4409 {
4410 	struct mount *mp;
4411 	struct vnode *vp;
4412 	int error;
4413 
4414 	error = priv_check(td, PRIV_VFS_FHSTAT);
4415 	if (error != 0)
4416 		return (error);
4417 	if ((mp = vfs_busyfs(&fh.fh_fsid)) == NULL)
4418 		return (ESTALE);
4419 	error = VFS_FHTOVP(mp, &fh.fh_fid, LK_EXCLUSIVE, &vp);
4420 	vfs_unbusy(mp);
4421 	if (error != 0)
4422 		return (error);
4423 	error = vn_stat(vp, sb, td->td_ucred, NOCRED, td);
4424 	vput(vp);
4425 	return (error);
4426 }
4427 
4428 /*
4429  * Implement fstatfs() for (NFS) file handles.
4430  */
4431 #ifndef _SYS_SYSPROTO_H_
4432 struct fhstatfs_args {
4433 	struct fhandle *u_fhp;
4434 	struct statfs *buf;
4435 };
4436 #endif
4437 int
4438 sys_fhstatfs(td, uap)
4439 	struct thread *td;
4440 	struct fhstatfs_args /* {
4441 		struct fhandle *u_fhp;
4442 		struct statfs *buf;
4443 	} */ *uap;
4444 {
4445 	struct statfs sf;
4446 	fhandle_t fh;
4447 	int error;
4448 
4449 	error = copyin(uap->u_fhp, &fh, sizeof(fhandle_t));
4450 	if (error != 0)
4451 		return (error);
4452 	error = kern_fhstatfs(td, fh, &sf);
4453 	if (error != 0)
4454 		return (error);
4455 	return (copyout(&sf, uap->buf, sizeof(sf)));
4456 }
4457 
4458 int
4459 kern_fhstatfs(struct thread *td, fhandle_t fh, struct statfs *buf)
4460 {
4461 	struct statfs *sp;
4462 	struct mount *mp;
4463 	struct vnode *vp;
4464 	int error;
4465 
4466 	error = priv_check(td, PRIV_VFS_FHSTATFS);
4467 	if (error != 0)
4468 		return (error);
4469 	if ((mp = vfs_busyfs(&fh.fh_fsid)) == NULL)
4470 		return (ESTALE);
4471 	error = VFS_FHTOVP(mp, &fh.fh_fid, LK_EXCLUSIVE, &vp);
4472 	if (error != 0) {
4473 		vfs_unbusy(mp);
4474 		return (error);
4475 	}
4476 	vput(vp);
4477 	error = prison_canseemount(td->td_ucred, mp);
4478 	if (error != 0)
4479 		goto out;
4480 #ifdef MAC
4481 	error = mac_mount_check_stat(td->td_ucred, mp);
4482 	if (error != 0)
4483 		goto out;
4484 #endif
4485 	/*
4486 	 * Set these in case the underlying filesystem fails to do so.
4487 	 */
4488 	sp = &mp->mnt_stat;
4489 	sp->f_version = STATFS_VERSION;
4490 	sp->f_namemax = NAME_MAX;
4491 	sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
4492 	error = VFS_STATFS(mp, sp);
4493 	if (error == 0)
4494 		*buf = *sp;
4495 out:
4496 	vfs_unbusy(mp);
4497 	return (error);
4498 }
4499 
4500 int
4501 kern_posix_fallocate(struct thread *td, int fd, off_t offset, off_t len)
4502 {
4503 	struct file *fp;
4504 	struct mount *mp;
4505 	struct vnode *vp;
4506 	cap_rights_t rights;
4507 	off_t olen, ooffset;
4508 	int error;
4509 
4510 	fp = NULL;
4511 	error = fget(td, fd, cap_rights_init(&rights, CAP_WRITE), &fp);
4512 	if (error != 0)
4513 		goto out;
4514 
4515 	switch (fp->f_type) {
4516 	case DTYPE_VNODE:
4517 		break;
4518 	case DTYPE_PIPE:
4519 	case DTYPE_FIFO:
4520 		error = ESPIPE;
4521 		goto out;
4522 	default:
4523 		error = ENODEV;
4524 		goto out;
4525 	}
4526 	if ((fp->f_flag & FWRITE) == 0) {
4527 		error = EBADF;
4528 		goto out;
4529 	}
4530 	vp = fp->f_vnode;
4531 	if (vp->v_type != VREG) {
4532 		error = ENODEV;
4533 		goto out;
4534 	}
4535 	if (offset < 0 || len <= 0) {
4536 		error = EINVAL;
4537 		goto out;
4538 	}
4539 	/* Check for wrap. */
4540 	if (offset > OFF_MAX - len) {
4541 		error = EFBIG;
4542 		goto out;
4543 	}
4544 
4545 	/* Allocating blocks may take a long time, so iterate. */
4546 	for (;;) {
4547 		olen = len;
4548 		ooffset = offset;
4549 
4550 		bwillwrite();
4551 		mp = NULL;
4552 		error = vn_start_write(vp, &mp, V_WAIT | PCATCH);
4553 		if (error != 0)
4554 			break;
4555 		error = vn_lock(vp, LK_EXCLUSIVE);
4556 		if (error != 0) {
4557 			vn_finished_write(mp);
4558 			break;
4559 		}
4560 #ifdef MAC
4561 		error = mac_vnode_check_write(td->td_ucred, fp->f_cred, vp);
4562 		if (error == 0)
4563 #endif
4564 			error = VOP_ALLOCATE(vp, &offset, &len);
4565 		VOP_UNLOCK(vp, 0);
4566 		vn_finished_write(mp);
4567 
4568 		if (olen + ooffset != offset + len) {
4569 			panic("offset + len changed from %jx/%jx to %jx/%jx",
4570 			    ooffset, olen, offset, len);
4571 		}
4572 		if (error != 0 || len == 0)
4573 			break;
4574 		KASSERT(olen > len, ("Iteration did not make progress?"));
4575 		maybe_yield();
4576 	}
4577  out:
4578 	if (fp != NULL)
4579 		fdrop(fp, td);
4580 	return (error);
4581 }
4582 
4583 int
4584 sys_posix_fallocate(struct thread *td, struct posix_fallocate_args *uap)
4585 {
4586 
4587 	return (kern_posix_fallocate(td, uap->fd, uap->offset, uap->len));
4588 }
4589 
4590 /*
4591  * Unlike madvise(2), we do not make a best effort to remember every
4592  * possible caching hint.  Instead, we remember the last setting with
4593  * the exception that we will allow POSIX_FADV_NORMAL to adjust the
4594  * region of any current setting.
4595  */
4596 int
4597 kern_posix_fadvise(struct thread *td, int fd, off_t offset, off_t len,
4598     int advice)
4599 {
4600 	struct fadvise_info *fa, *new;
4601 	struct file *fp;
4602 	struct vnode *vp;
4603 	cap_rights_t rights;
4604 	off_t end;
4605 	int error;
4606 
4607 	if (offset < 0 || len < 0 || offset > OFF_MAX - len)
4608 		return (EINVAL);
4609 	switch (advice) {
4610 	case POSIX_FADV_SEQUENTIAL:
4611 	case POSIX_FADV_RANDOM:
4612 	case POSIX_FADV_NOREUSE:
4613 		new = malloc(sizeof(*fa), M_FADVISE, M_WAITOK);
4614 		break;
4615 	case POSIX_FADV_NORMAL:
4616 	case POSIX_FADV_WILLNEED:
4617 	case POSIX_FADV_DONTNEED:
4618 		new = NULL;
4619 		break;
4620 	default:
4621 		return (EINVAL);
4622 	}
4623 	/* XXX: CAP_POSIX_FADVISE? */
4624 	error = fget(td, fd, cap_rights_init(&rights), &fp);
4625 	if (error != 0)
4626 		goto out;
4627 
4628 	switch (fp->f_type) {
4629 	case DTYPE_VNODE:
4630 		break;
4631 	case DTYPE_PIPE:
4632 	case DTYPE_FIFO:
4633 		error = ESPIPE;
4634 		goto out;
4635 	default:
4636 		error = ENODEV;
4637 		goto out;
4638 	}
4639 	vp = fp->f_vnode;
4640 	if (vp->v_type != VREG) {
4641 		error = ENODEV;
4642 		goto out;
4643 	}
4644 	if (len == 0)
4645 		end = OFF_MAX;
4646 	else
4647 		end = offset + len - 1;
4648 	switch (advice) {
4649 	case POSIX_FADV_SEQUENTIAL:
4650 	case POSIX_FADV_RANDOM:
4651 	case POSIX_FADV_NOREUSE:
4652 		/*
4653 		 * Try to merge any existing non-standard region with
4654 		 * this new region if possible, otherwise create a new
4655 		 * non-standard region for this request.
4656 		 */
4657 		mtx_pool_lock(mtxpool_sleep, fp);
4658 		fa = fp->f_advice;
4659 		if (fa != NULL && fa->fa_advice == advice &&
4660 		    ((fa->fa_start <= end && fa->fa_end >= offset) ||
4661 		    (end != OFF_MAX && fa->fa_start == end + 1) ||
4662 		    (fa->fa_end != OFF_MAX && fa->fa_end + 1 == offset))) {
4663 			if (offset < fa->fa_start)
4664 				fa->fa_start = offset;
4665 			if (end > fa->fa_end)
4666 				fa->fa_end = end;
4667 		} else {
4668 			new->fa_advice = advice;
4669 			new->fa_start = offset;
4670 			new->fa_end = end;
4671 			new->fa_prevstart = 0;
4672 			new->fa_prevend = 0;
4673 			fp->f_advice = new;
4674 			new = fa;
4675 		}
4676 		mtx_pool_unlock(mtxpool_sleep, fp);
4677 		break;
4678 	case POSIX_FADV_NORMAL:
4679 		/*
4680 		 * If a the "normal" region overlaps with an existing
4681 		 * non-standard region, trim or remove the
4682 		 * non-standard region.
4683 		 */
4684 		mtx_pool_lock(mtxpool_sleep, fp);
4685 		fa = fp->f_advice;
4686 		if (fa != NULL) {
4687 			if (offset <= fa->fa_start && end >= fa->fa_end) {
4688 				new = fa;
4689 				fp->f_advice = NULL;
4690 			} else if (offset <= fa->fa_start &&
4691 			    end >= fa->fa_start)
4692 				fa->fa_start = end + 1;
4693 			else if (offset <= fa->fa_end && end >= fa->fa_end)
4694 				fa->fa_end = offset - 1;
4695 			else if (offset >= fa->fa_start && end <= fa->fa_end) {
4696 				/*
4697 				 * If the "normal" region is a middle
4698 				 * portion of the existing
4699 				 * non-standard region, just remove
4700 				 * the whole thing rather than picking
4701 				 * one side or the other to
4702 				 * preserve.
4703 				 */
4704 				new = fa;
4705 				fp->f_advice = NULL;
4706 			}
4707 		}
4708 		mtx_pool_unlock(mtxpool_sleep, fp);
4709 		break;
4710 	case POSIX_FADV_WILLNEED:
4711 	case POSIX_FADV_DONTNEED:
4712 		error = VOP_ADVISE(vp, offset, end, advice);
4713 		break;
4714 	}
4715 out:
4716 	if (fp != NULL)
4717 		fdrop(fp, td);
4718 	free(new, M_FADVISE);
4719 	return (error);
4720 }
4721 
4722 int
4723 sys_posix_fadvise(struct thread *td, struct posix_fadvise_args *uap)
4724 {
4725 
4726 	return (kern_posix_fadvise(td, uap->fd, uap->offset, uap->len,
4727 	    uap->advice));
4728 }
4729