xref: /freebsd/sys/kern/vfs_extattr.c (revision af23369a6deaaeb612ab266eb88b8bb8d560c322)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 1999-2001 Robert N. M. Watson
5  * All rights reserved.
6  *
7  * This software was developed by Robert Watson for the TrustedBSD Project.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
33 
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/capsicum.h>
37 #include <sys/lock.h>
38 #include <sys/mount.h>
39 #include <sys/mutex.h>
40 #include <sys/sysproto.h>
41 #include <sys/fcntl.h>
42 #include <sys/namei.h>
43 #include <sys/filedesc.h>
44 #include <sys/limits.h>
45 #include <sys/vnode.h>
46 #include <sys/proc.h>
47 #include <sys/extattr.h>
48 
49 #include <security/audit/audit.h>
50 #include <security/mac/mac_framework.h>
51 
52 static int	kern_extattr_set_path(struct thread *td, const char *path,
53 		    int attrnamespace, const char *attrname, void *data,
54 		    size_t nbytes, int follow);
55 static int	kern_extattr_get_path(struct thread *td, const char *path,
56 		    int attrnamespace, const char *attrname, void *data,
57 		    size_t nbytes, int follow);
58 static int	kern_extattr_delete_path(struct thread *td, const char *path,
59 		    int attrnamespace, const char *attrname, int follow);
60 static int	kern_extattr_list_path(struct thread *td, const char *path,
61 		    int attrnamespace, void *data, size_t nbytes, int follow);
62 
63 /*
64  * Syscall to push extended attribute configuration information into the VFS.
65  * Accepts a path, which it converts to a mountpoint, as well as a command
66  * (int cmd), and attribute name and misc data.
67  *
68  * Currently this is used only by UFS1 extended attributes.
69  */
70 #ifndef _SYS_SYSPROTO_H_
71 struct extattrctl_args {
72 	const char *path;
73 	int cmd;
74 	const char *filename;
75 	int attrnamespace;
76 	const char *attrname;
77 };
78 #endif
79 int
80 sys_extattrctl(struct thread *td, struct extattrctl_args *uap)
81 {
82 	struct vnode *filename_vp;
83 	struct nameidata nd;
84 	struct mount *mp, *mp_writable;
85 	char attrname[EXTATTR_MAXNAMELEN + 1];
86 	int error;
87 
88 	AUDIT_ARG_CMD(uap->cmd);
89 	AUDIT_ARG_VALUE(uap->attrnamespace);
90 	/*
91 	 * uap->attrname is not always defined.  We check again later when we
92 	 * invoke the VFS call so as to pass in NULL there if needed.
93 	 */
94 	if (uap->attrname != NULL) {
95 		error = copyinstr(uap->attrname, attrname, sizeof(attrname),
96 		    NULL);
97 		if (error)
98 			return (error);
99 	}
100 	AUDIT_ARG_TEXT(attrname);
101 
102 	mp = NULL;
103 	filename_vp = NULL;
104 	if (uap->filename != NULL) {
105 		NDINIT(&nd, LOOKUP, FOLLOW | AUDITVNODE2, UIO_USERSPACE,
106 		    uap->filename);
107 		error = namei(&nd);
108 		if (error)
109 			return (error);
110 		filename_vp = nd.ni_vp;
111 		NDFREE_PNBUF(&nd);
112 	}
113 
114 	/* uap->path is always defined. */
115 	NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | AUDITVNODE1, UIO_USERSPACE,
116 	    uap->path);
117 	error = namei(&nd);
118 	if (error)
119 		goto out;
120 	mp = nd.ni_vp->v_mount;
121 	error = vfs_busy(mp, 0);
122 	if (error) {
123 		vput(nd.ni_vp);
124 		NDFREE_PNBUF(&nd);
125 		mp = NULL;
126 		goto out;
127 	}
128 	VOP_UNLOCK(nd.ni_vp);
129 	error = vn_start_write(nd.ni_vp, &mp_writable, V_WAIT | V_PCATCH);
130 	vrele(nd.ni_vp);
131 	NDFREE_PNBUF(&nd);
132 	if (error)
133 		goto out;
134 	if (filename_vp != NULL) {
135 		/*
136 		 * uap->filename is not always defined.  If it is,
137 		 * grab a vnode lock, which VFS_EXTATTRCTL() will
138 		 * later release.
139 		 */
140 		error = vn_lock(filename_vp, LK_EXCLUSIVE);
141 		if (error) {
142 			vn_finished_write(mp_writable);
143 			goto out;
144 		}
145 	}
146 
147 	error = VFS_EXTATTRCTL(mp, uap->cmd, filename_vp, uap->attrnamespace,
148 	    uap->attrname != NULL ? attrname : NULL);
149 
150 	vn_finished_write(mp_writable);
151 out:
152 	if (mp != NULL)
153 		vfs_unbusy(mp);
154 
155 	/*
156 	 * VFS_EXTATTRCTL will have unlocked, but not de-ref'd, filename_vp,
157 	 * so vrele it if it is defined.
158 	 */
159 	if (filename_vp != NULL)
160 		vrele(filename_vp);
161 	return (error);
162 }
163 
164 /*-
165  * Set a named extended attribute on a file or directory
166  *
167  * Arguments: unlocked vnode "vp", attribute namespace "attrnamespace",
168  *            kernelspace string pointer "attrname", userspace buffer
169  *            pointer "data", buffer length "nbytes", thread "td".
170  * Returns: 0 on success, an error number otherwise
171  * Locks: none
172  * References: vp must be a valid reference for the duration of the call
173  */
174 static int
175 extattr_set_vp(struct vnode *vp, int attrnamespace, const char *attrname,
176     void *data, size_t nbytes, struct thread *td)
177 {
178 	struct mount *mp;
179 	struct uio auio;
180 	struct iovec aiov;
181 	ssize_t cnt;
182 	int error;
183 
184 	if (nbytes > IOSIZE_MAX)
185 		return (EINVAL);
186 
187 	error = vn_start_write(vp, &mp, V_WAIT | V_PCATCH);
188 	if (error)
189 		return (error);
190 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
191 
192 	aiov.iov_base = data;
193 	aiov.iov_len = nbytes;
194 	auio.uio_iov = &aiov;
195 	auio.uio_iovcnt = 1;
196 	auio.uio_offset = 0;
197 	auio.uio_resid = nbytes;
198 	auio.uio_rw = UIO_WRITE;
199 	auio.uio_segflg = UIO_USERSPACE;
200 	auio.uio_td = td;
201 	cnt = nbytes;
202 
203 #ifdef MAC
204 	error = mac_vnode_check_setextattr(td->td_ucred, vp, attrnamespace,
205 	    attrname);
206 	if (error)
207 		goto done;
208 #endif
209 
210 	error = VOP_SETEXTATTR(vp, attrnamespace, attrname, &auio,
211 	    td->td_ucred, td);
212 	cnt -= auio.uio_resid;
213 	td->td_retval[0] = cnt;
214 
215 #ifdef MAC
216 done:
217 #endif
218 	VOP_UNLOCK(vp);
219 	vn_finished_write(mp);
220 	return (error);
221 }
222 
223 #ifndef _SYS_SYSPROTO_H_
224 struct extattr_set_fd_args {
225 	int fd;
226 	int attrnamespace;
227 	const char *attrname;
228 	void *data;
229 	size_t nbytes;
230 };
231 #endif
232 int
233 sys_extattr_set_fd(struct thread *td, struct extattr_set_fd_args *uap)
234 {
235 	struct file *fp;
236 	char attrname[EXTATTR_MAXNAMELEN + 1];
237 	cap_rights_t rights;
238 	int error;
239 
240 	AUDIT_ARG_FD(uap->fd);
241 	AUDIT_ARG_VALUE(uap->attrnamespace);
242 	error = copyinstr(uap->attrname, attrname, sizeof(attrname), NULL);
243 	if (error)
244 		return (error);
245 	AUDIT_ARG_TEXT(attrname);
246 
247 	error = getvnode_path(td, uap->fd,
248 	    cap_rights_init_one(&rights, CAP_EXTATTR_SET), &fp);
249 	if (error)
250 		return (error);
251 
252 	error = extattr_set_vp(fp->f_vnode, uap->attrnamespace,
253 	    attrname, uap->data, uap->nbytes, td);
254 	fdrop(fp, td);
255 
256 	return (error);
257 }
258 
259 #ifndef _SYS_SYSPROTO_H_
260 struct extattr_set_file_args {
261 	const char *path;
262 	int attrnamespace;
263 	const char *attrname;
264 	void *data;
265 	size_t nbytes;
266 };
267 #endif
268 int
269 sys_extattr_set_file(struct thread *td, struct extattr_set_file_args *uap)
270 {
271 
272 	return (kern_extattr_set_path(td, uap->path, uap->attrnamespace,
273 	    uap->attrname, uap->data, uap->nbytes, FOLLOW));
274 }
275 
276 #ifndef _SYS_SYSPROTO_H_
277 struct extattr_set_link_args {
278 	const char *path;
279 	int attrnamespace;
280 	const char *attrname;
281 	void *data;
282 	size_t nbytes;
283 };
284 #endif
285 int
286 sys_extattr_set_link(struct thread *td, struct extattr_set_link_args *uap)
287 {
288 
289 	return (kern_extattr_set_path(td, uap->path, uap->attrnamespace,
290 	    uap->attrname, uap->data, uap->nbytes, NOFOLLOW));
291 }
292 
293 static int
294 kern_extattr_set_path(struct thread *td, const char *path, int attrnamespace,
295     const char *uattrname, void *data, size_t nbytes, int follow)
296 {
297 	struct nameidata nd;
298 	char attrname[EXTATTR_MAXNAMELEN + 1];
299 	int error;
300 
301 	AUDIT_ARG_VALUE(attrnamespace);
302 	error = copyinstr(uattrname, attrname, sizeof(attrname), NULL);
303 	if (error)
304 		return (error);
305 	AUDIT_ARG_TEXT(attrname);
306 
307 	NDINIT(&nd, LOOKUP, follow | AUDITVNODE1, UIO_USERSPACE, path);
308 	error = namei(&nd);
309 	if (error)
310 		return (error);
311 	NDFREE_PNBUF(&nd);
312 
313 	error = extattr_set_vp(nd.ni_vp, attrnamespace, attrname, data,
314 	    nbytes, td);
315 
316 	vrele(nd.ni_vp);
317 	return (error);
318 }
319 
320 /*-
321  * Get a named extended attribute on a file or directory
322  *
323  * Arguments: unlocked vnode "vp", attribute namespace "attrnamespace",
324  *            kernelspace string pointer "attrname", userspace buffer
325  *            pointer "data", buffer length "nbytes", thread "td".
326  * Returns: 0 on success, an error number otherwise
327  * Locks: none
328  * References: vp must be a valid reference for the duration of the call
329  */
330 static int
331 extattr_get_vp(struct vnode *vp, int attrnamespace, const char *attrname,
332     void *data, size_t nbytes, struct thread *td)
333 {
334 	struct uio auio, *auiop;
335 	struct iovec aiov;
336 	ssize_t cnt;
337 	size_t size, *sizep;
338 	int error;
339 
340 	if (nbytes > IOSIZE_MAX)
341 		return (EINVAL);
342 
343 	vn_lock(vp, LK_SHARED | LK_RETRY);
344 
345 	/*
346 	 * Slightly unusual semantics: if the user provides a NULL data
347 	 * pointer, they don't want to receive the data, just the maximum
348 	 * read length.
349 	 */
350 	auiop = NULL;
351 	sizep = NULL;
352 	cnt = 0;
353 	if (data != NULL) {
354 		aiov.iov_base = data;
355 		aiov.iov_len = nbytes;
356 		auio.uio_iov = &aiov;
357 		auio.uio_iovcnt = 1;
358 		auio.uio_offset = 0;
359 		auio.uio_resid = nbytes;
360 		auio.uio_rw = UIO_READ;
361 		auio.uio_segflg = UIO_USERSPACE;
362 		auio.uio_td = td;
363 		auiop = &auio;
364 		cnt = nbytes;
365 	} else
366 		sizep = &size;
367 
368 #ifdef MAC
369 	error = mac_vnode_check_getextattr(td->td_ucred, vp, attrnamespace,
370 	    attrname);
371 	if (error)
372 		goto done;
373 #endif
374 
375 	error = VOP_GETEXTATTR(vp, attrnamespace, attrname, auiop, sizep,
376 	    td->td_ucred, td);
377 
378 	if (auiop != NULL) {
379 		cnt -= auio.uio_resid;
380 		td->td_retval[0] = cnt;
381 	} else
382 		td->td_retval[0] = size;
383 #ifdef MAC
384 done:
385 #endif
386 	VOP_UNLOCK(vp);
387 	return (error);
388 }
389 
390 #ifndef _SYS_SYSPROTO_H_
391 struct extattr_get_fd_args {
392 	int fd;
393 	int attrnamespace;
394 	const char *attrname;
395 	void *data;
396 	size_t nbytes;
397 };
398 #endif
399 int
400 sys_extattr_get_fd(struct thread *td, struct extattr_get_fd_args *uap)
401 {
402 	struct file *fp;
403 	char attrname[EXTATTR_MAXNAMELEN + 1];
404 	cap_rights_t rights;
405 	int error;
406 
407 	AUDIT_ARG_FD(uap->fd);
408 	AUDIT_ARG_VALUE(uap->attrnamespace);
409 	error = copyinstr(uap->attrname, attrname, sizeof(attrname), NULL);
410 	if (error)
411 		return (error);
412 	AUDIT_ARG_TEXT(attrname);
413 
414 	error = getvnode_path(td, uap->fd,
415 	    cap_rights_init_one(&rights, CAP_EXTATTR_GET), &fp);
416 	if (error)
417 		return (error);
418 
419 	error = extattr_get_vp(fp->f_vnode, uap->attrnamespace,
420 	    attrname, uap->data, uap->nbytes, td);
421 
422 	fdrop(fp, td);
423 	return (error);
424 }
425 
426 #ifndef _SYS_SYSPROTO_H_
427 struct extattr_get_file_args {
428 	const char *path;
429 	int attrnamespace;
430 	const char *attrname;
431 	void *data;
432 	size_t nbytes;
433 };
434 #endif
435 int
436 sys_extattr_get_file(struct thread *td, struct extattr_get_file_args *uap)
437 {
438 	return (kern_extattr_get_path(td, uap->path, uap->attrnamespace,
439 	    uap->attrname, uap->data, uap->nbytes, FOLLOW));
440 }
441 
442 #ifndef _SYS_SYSPROTO_H_
443 struct extattr_get_link_args {
444 	const char *path;
445 	int attrnamespace;
446 	const char *attrname;
447 	void *data;
448 	size_t nbytes;
449 };
450 #endif
451 int
452 sys_extattr_get_link(struct thread *td, struct extattr_get_link_args *uap)
453 {
454 	return (kern_extattr_get_path(td, uap->path, uap->attrnamespace,
455 	    uap->attrname, uap->data, uap->nbytes, NOFOLLOW));
456 }
457 
458 static int
459 kern_extattr_get_path(struct thread *td, const char *path, int attrnamespace,
460     const char *uattrname, void *data, size_t nbytes, int follow)
461 {
462 	struct nameidata nd;
463 	char attrname[EXTATTR_MAXNAMELEN + 1];
464 	int error;
465 
466 	AUDIT_ARG_VALUE(attrnamespace);
467 	error = copyinstr(uattrname, attrname, sizeof(attrname), NULL);
468 	if (error)
469 		return (error);
470 	AUDIT_ARG_TEXT(attrname);
471 
472 	NDINIT(&nd, LOOKUP, follow | AUDITVNODE1, UIO_USERSPACE, path);
473 	error = namei(&nd);
474 	if (error)
475 		return (error);
476 	NDFREE_PNBUF(&nd);
477 
478 	error = extattr_get_vp(nd.ni_vp, attrnamespace, attrname, data,
479 	    nbytes, td);
480 
481 	vrele(nd.ni_vp);
482 	return (error);
483 }
484 
485 /*
486  * extattr_delete_vp(): Delete a named extended attribute on a file or
487  *                      directory
488  *
489  * Arguments: unlocked vnode "vp", attribute namespace "attrnamespace",
490  *            kernelspace string pointer "attrname", proc "p"
491  * Returns: 0 on success, an error number otherwise
492  * Locks: none
493  * References: vp must be a valid reference for the duration of the call
494  */
495 static int
496 extattr_delete_vp(struct vnode *vp, int attrnamespace, const char *attrname,
497     struct thread *td)
498 {
499 	struct mount *mp;
500 	int error;
501 
502 	error = vn_start_write(vp, &mp, V_WAIT | V_PCATCH);
503 	if (error)
504 		return (error);
505 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
506 
507 #ifdef MAC
508 	error = mac_vnode_check_deleteextattr(td->td_ucred, vp, attrnamespace,
509 	    attrname);
510 	if (error)
511 		goto done;
512 #endif
513 
514 	error = VOP_DELETEEXTATTR(vp, attrnamespace, attrname, td->td_ucred,
515 	    td);
516 	if (error == EOPNOTSUPP)
517 		error = VOP_SETEXTATTR(vp, attrnamespace, attrname, NULL,
518 		    td->td_ucred, td);
519 #ifdef MAC
520 done:
521 #endif
522 	VOP_UNLOCK(vp);
523 	vn_finished_write(mp);
524 	return (error);
525 }
526 
527 #ifndef _SYS_SYSPROTO_H_
528 struct extattr_delete_fd_args {
529 	int fd;
530 	int attrnamespace;
531 	const char *attrname;
532 };
533 #endif
534 int
535 sys_extattr_delete_fd(struct thread *td, struct extattr_delete_fd_args *uap)
536 {
537 	struct file *fp;
538 	char attrname[EXTATTR_MAXNAMELEN + 1];
539 	cap_rights_t rights;
540 	int error;
541 
542 	AUDIT_ARG_FD(uap->fd);
543 	AUDIT_ARG_VALUE(uap->attrnamespace);
544 	error = copyinstr(uap->attrname, attrname, sizeof(attrname), NULL);
545 	if (error)
546 		return (error);
547 	AUDIT_ARG_TEXT(attrname);
548 
549 	error = getvnode_path(td, uap->fd,
550 	    cap_rights_init_one(&rights, CAP_EXTATTR_DELETE), &fp);
551 	if (error)
552 		return (error);
553 
554 	error = extattr_delete_vp(fp->f_vnode, uap->attrnamespace,
555 	    attrname, td);
556 	fdrop(fp, td);
557 	return (error);
558 }
559 
560 #ifndef _SYS_SYSPROTO_H_
561 struct extattr_delete_file_args {
562 	const char *path;
563 	int attrnamespace;
564 	const char *attrname;
565 };
566 #endif
567 int
568 sys_extattr_delete_file(struct thread *td, struct extattr_delete_file_args *uap)
569 {
570 
571 	return (kern_extattr_delete_path(td, uap->path, uap->attrnamespace,
572 	    uap->attrname, FOLLOW));
573 }
574 
575 #ifndef _SYS_SYSPROTO_H_
576 struct extattr_delete_link_args {
577 	const char *path;
578 	int attrnamespace;
579 	const char *attrname;
580 };
581 #endif
582 int
583 sys_extattr_delete_link(struct thread *td, struct extattr_delete_link_args *uap)
584 {
585 
586 	return (kern_extattr_delete_path(td, uap->path, uap->attrnamespace,
587 	    uap->attrname, NOFOLLOW));
588 }
589 
590 static int
591 kern_extattr_delete_path(struct thread *td, const char *path, int attrnamespace,
592     const char *uattrname, int follow)
593 {
594 	struct nameidata nd;
595 	char attrname[EXTATTR_MAXNAMELEN + 1];
596 	int error;
597 
598 	AUDIT_ARG_VALUE(attrnamespace);
599 	error = copyinstr(uattrname, attrname, sizeof(attrname), NULL);
600 	if (error)
601 		return(error);
602 	AUDIT_ARG_TEXT(attrname);
603 
604 	NDINIT(&nd, LOOKUP, follow | AUDITVNODE1, UIO_USERSPACE, path);
605 	error = namei(&nd);
606 	if (error)
607 		return(error);
608 	NDFREE_PNBUF(&nd);
609 
610 	error = extattr_delete_vp(nd.ni_vp, attrnamespace, attrname, td);
611 	vrele(nd.ni_vp);
612 	return(error);
613 }
614 
615 /*-
616  * Retrieve a list of extended attributes on a file or directory.
617  *
618  * Arguments: unlocked vnode "vp", attribute namespace 'attrnamespace",
619  *            userspace buffer pointer "data", buffer length "nbytes",
620  *            thread "td".
621  * Returns: 0 on success, an error number otherwise
622  * Locks: none
623  * References: vp must be a valid reference for the duration of the call
624  */
625 static int
626 extattr_list_vp(struct vnode *vp, int attrnamespace, void *data,
627     size_t nbytes, struct thread *td)
628 {
629 	struct uio auio, *auiop;
630 	size_t size, *sizep;
631 	struct iovec aiov;
632 	ssize_t cnt;
633 	int error;
634 
635 	if (nbytes > IOSIZE_MAX)
636 		return (EINVAL);
637 
638 	auiop = NULL;
639 	sizep = NULL;
640 	cnt = 0;
641 	if (data != NULL) {
642 		aiov.iov_base = data;
643 		aiov.iov_len = nbytes;
644 		auio.uio_iov = &aiov;
645 		auio.uio_iovcnt = 1;
646 		auio.uio_offset = 0;
647 		auio.uio_resid = nbytes;
648 		auio.uio_rw = UIO_READ;
649 		auio.uio_segflg = UIO_USERSPACE;
650 		auio.uio_td = td;
651 		auiop = &auio;
652 		cnt = nbytes;
653 	} else
654 		sizep = &size;
655 
656 	vn_lock(vp, LK_SHARED | LK_RETRY);
657 
658 #ifdef MAC
659 	error = mac_vnode_check_listextattr(td->td_ucred, vp, attrnamespace);
660 	if (error) {
661 		VOP_UNLOCK(vp);
662 		return (error);
663 	}
664 #endif
665 
666 	error = VOP_LISTEXTATTR(vp, attrnamespace, auiop, sizep,
667 	    td->td_ucred, td);
668 	VOP_UNLOCK(vp);
669 
670 	if (auiop != NULL) {
671 		cnt -= auio.uio_resid;
672 		td->td_retval[0] = cnt;
673 	} else
674 		td->td_retval[0] = size;
675 	return (error);
676 }
677 
678 #ifndef _SYS_SYSPROTO_H_
679 struct extattr_list_fd_args {
680 	int fd;
681 	int attrnamespace;
682 	void *data;
683 	size_t nbytes;
684 };
685 #endif
686 int
687 sys_extattr_list_fd(struct thread *td, struct extattr_list_fd_args *uap)
688 {
689 	struct file *fp;
690 	cap_rights_t rights;
691 	int error;
692 
693 	AUDIT_ARG_FD(uap->fd);
694 	AUDIT_ARG_VALUE(uap->attrnamespace);
695 	error = getvnode_path(td, uap->fd,
696 	    cap_rights_init_one(&rights, CAP_EXTATTR_LIST), &fp);
697 	if (error)
698 		return (error);
699 
700 	error = extattr_list_vp(fp->f_vnode, uap->attrnamespace, uap->data,
701 	    uap->nbytes, td);
702 
703 	fdrop(fp, td);
704 	return (error);
705 }
706 
707 #ifndef _SYS_SYSPROTO_H_
708 struct extattr_list_file_args {
709 	const char *path;
710 	int attrnamespace;
711 	void *data;
712 	size_t nbytes;
713 }
714 #endif
715 int
716 sys_extattr_list_file(struct thread *td, struct extattr_list_file_args *uap)
717 {
718 
719 	return (kern_extattr_list_path(td, uap->path, uap->attrnamespace,
720 	    uap->data, uap->nbytes, FOLLOW));
721 }
722 
723 #ifndef _SYS_SYSPROTO_H_
724 struct extattr_list_link_args {
725 	const char *path;
726 	int attrnamespace;
727 	void *data;
728 	size_t nbytes;
729 };
730 #endif
731 int
732 sys_extattr_list_link(struct thread *td, struct extattr_list_link_args *uap)
733 {
734 
735 	return (kern_extattr_list_path(td, uap->path, uap->attrnamespace,
736 	    uap->data, uap->nbytes, NOFOLLOW));
737 }
738 
739 static int
740 kern_extattr_list_path(struct thread *td, const char *path, int attrnamespace,
741     void *data, size_t nbytes, int follow)
742 {
743 	struct nameidata nd;
744 	int error;
745 
746 	AUDIT_ARG_VALUE(attrnamespace);
747 	NDINIT(&nd, LOOKUP, follow | AUDITVNODE1, UIO_USERSPACE, path);
748 	error = namei(&nd);
749 	if (error)
750 		return (error);
751 	NDFREE_PNBUF(&nd);
752 
753 	error = extattr_list_vp(nd.ni_vp, attrnamespace, data, nbytes, td);
754 
755 	vrele(nd.ni_vp);
756 	return (error);
757 }
758