mask.c revision 99110 
1/*
2 * Copyright (c) 2001-2002 Chris D. Faulhaber
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR THE VOICES IN HIS HEAD BE
18 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
19 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
20 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
21 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
22 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
23 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
24 * POSSIBILITY OF SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD: head/bin/setfacl/mask.c 99110 2002-06-30 05:15:05Z obrien $");
29
30#include <sys/types.h>
31#include <sys/acl.h>
32#include <sys/stat.h>
33
34#include <err.h>
35#include <errno.h>
36#include <stdio.h>
37#include <stdlib.h>
38
39#include "setfacl.h"
40
41/* set the appropriate mask the given ACL's */
42int
43set_acl_mask(acl_t *prev_acl)
44{
45	acl_entry_t entry;
46	acl_t acl;
47	acl_tag_t tag;
48	int entry_id;
49
50	entry = NULL;
51
52	/*
53	 * ... if a mask entry is specified, then the permissions of the mask
54	 * entry in the resulting ACL shall be set to the permissions in the
55	 * specified ACL mask entry.
56	 */
57	if (have_mask)
58		return (0);
59
60	acl = acl_dup(*prev_acl);
61	if (acl == NULL)
62		err(1, "acl_dup() failed");
63
64	if (n_flag == 0) {
65		/*
66		 * If no mask entry is specified and the -n option is not
67		 * specified, then the permissions of the resulting ACL mask
68		 * entry shall be set to the union of the permissions
69		 * associated with all entries which belong to the file group
70		 * class in the resulting ACL
71		 */
72		if (acl_calc_mask(&acl)) {
73			warn("acl_calc_mask() failed");
74			acl_free(acl);
75			return (-1);
76		}
77	} else {
78		/*
79		 * If no mask entry is specified and the -n option is
80		 * specified, then the permissions of the resulting ACL
81		 * mask entry shall remain unchanged ...
82		 */
83
84		entry_id = ACL_FIRST_ENTRY;
85
86		while (acl_get_entry(acl, entry_id, &entry) == 1) {
87			entry_id = ACL_NEXT_ENTRY;
88			if (acl_get_tag_type(entry, &tag) == -1)
89				err(1, "acl_get_tag_type() failed");
90
91			if (tag == ACL_MASK) {
92				acl_free(acl);
93				return (0);
94			}
95		}
96
97		/*
98		 * If no mask entry is specified, the -n option is specified,
99		 * and no ACL mask entry exists in the ACL associated with the
100		 * file, then write an error message to standard error and
101		 * continue with the next file.
102		 */
103		warnx("warning: no mask entry");
104		acl_free(acl);
105		return (0);
106	}
107
108	acl_free(*prev_acl);
109	*prev_acl = acl_dup(acl);
110	acl_free(acl);
111
112	return (0);
113}
114