1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include <unistd.h>
30 #include <stdlib.h>
31 #include <string.h>
32 #include <libgen.h>
33 #include <attr.h>
34 #include <fcntl.h>
35 #include <errno.h>
36 #include "libcmdutils.h"
37 
38 /*
39  * Returns the status of attempting to obtain the extended system
40  * attributes in the specified view.
41  *
42  * Note: If obtaining status for an extended attribute file, the caller must
43  * chdir into the hidden directory prior to calling sysattr_status().
44  *
45  * Returns 1 if the extended system attributes were obtained, otherwise
46  * returns 0.
47  */
48 int
sysattr_status(char * file,xattr_view_t view)49 sysattr_status(char *file, xattr_view_t view)
50 {
51 	nvlist_t	*response = NULL;
52 	int		saveerrno;
53 	int		status;
54 
55 	status = getattrat(AT_FDCWD, view, file, &response);
56 
57 	saveerrno = errno;
58 	if (response)
59 		(void) nvlist_free(response);
60 	errno = saveerrno;
61 
62 	return (status == 0);
63 }
64 
65 /*
66  * Returns the type of the specified in file.  If the file name matches
67  * the name of either a read-only or read-write extended system attribute
68  * file then sysattr_type() returns the type of file:
69  * 	return value	file type
70  *	------------	---------
71  *	_RO_SATTR	read-only extended system attribute file
72  *	_RW_SATTR	read-write extended system attribute file
73  *	_NOT_SATTR	neither a read-only or read-write extended system
74  *			attribute file.
75  */
76 int
sysattr_type(char * file)77 sysattr_type(char *file)
78 {
79 	if (file == NULL) {
80 		errno = ENOENT;
81 		return (_NOT_SATTR);
82 	}
83 
84 	if (strcmp(basename(file), file) != 0) {
85 		errno = EINVAL;
86 		return (_NOT_SATTR);
87 	}
88 
89 	errno = 0;
90 	if (strcmp(file, VIEW_READONLY) == 0) {
91 		return (_RO_SATTR);
92 	} else if (strcmp(file, VIEW_READWRITE) == 0) {
93 		return (_RW_SATTR);
94 	} else {
95 		return (_NOT_SATTR);
96 	}
97 }
98 
99 /*
100  * Call sysattr_support() instead of pathconf(file, _PC_SATTR_ENABLED) or
101  * pathconf(file, _PC_SATTR_EXISTS) so that if pathconf() fails over NFS, we
102  * can still try to figure out if extended system attributes are supported by
103  * testing for a valid extended system attribute file.
104  *
105  * 'name' can have the values _PC_SATTR_ENABLED or _PC_SATTR_EXISTS.
106  *
107  * Returns 1 if the underlying file system supports extended system attributes,
108  * otherwise, returns -1.
109  */
110 int
sysattr_support(char * file,int name)111 sysattr_support(char *file, int name)
112 {
113 	int	rc;
114 
115 	errno = 0;
116 	if ((name != _PC_SATTR_ENABLED) &&
117 	    (name != _PC_SATTR_EXISTS)) {
118 		errno = EINVAL;
119 		return (-1);
120 	}
121 	if (((rc = pathconf(file, name)) == 1) || (errno != EINVAL)) {
122 		return (rc);
123 	}
124 	return (sysattr_status(file, XATTR_VIEW_READONLY));
125 }
126