xref: /netbsd-src/lib/libc/posix1e/acl_perm.c (revision 9aa2a9c323eb12a08584c70d6ea91d316703d3fe)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2001-2002 Chris D. Faulhaber
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 #if 0
31 __FBSDID("$FreeBSD: head/lib/libc/posix1e/acl_perm.c 326193 2017-11-25 17:12:48Z pfg $");
32 #else
33 __RCSID("$NetBSD: acl_perm.c,v 1.1 2020/05/16 18:31:47 christos Exp $");
34 #endif
35 
36 #include "namespace.h"
37 #include <sys/types.h>
38 #include <sys/acl.h>
39 
40 #include <errno.h>
41 #include <string.h>
42 
43 static int
_perm_is_invalid(acl_perm_t perm)44 _perm_is_invalid(acl_perm_t perm)
45 {
46 
47 	/* Check if more than a single bit is set. */
48 	if ((perm & -perm) == perm &&
49 	    (perm & (ACL_POSIX1E_BITS | ACL_NFS4_PERM_BITS)) == perm)
50 		return (0);
51 
52 	errno = EINVAL;
53 
54 	return (1);
55 }
56 
57 /*
58  * acl_add_perm() (23.4.1): add the permission contained in perm to the
59  * permission set permset_d
60  */
61 int
acl_add_perm(acl_permset_t permset_d,acl_perm_t perm)62 acl_add_perm(acl_permset_t permset_d, acl_perm_t perm)
63 {
64 
65 	if (permset_d == NULL) {
66 		errno = EINVAL;
67 		return (-1);
68 	}
69 
70 	if (_perm_is_invalid(perm))
71 		return (-1);
72 
73 	*permset_d |= perm;
74 
75 	return (0);
76 }
77 
78 /*
79  * acl_clear_perms() (23.4.3): clear all permisions from the permission
80  * set permset_d
81  */
82 int
acl_clear_perms(acl_permset_t permset_d)83 acl_clear_perms(acl_permset_t permset_d)
84 {
85 
86 	if (permset_d == NULL) {
87 		errno = EINVAL;
88 		return (-1);
89 	}
90 
91 	*permset_d = ACL_PERM_NONE;
92 
93 	return (0);
94 }
95 
96 /*
97  * acl_delete_perm() (23.4.10): remove the permission in perm from the
98  * permission set permset_d
99  */
100 int
acl_delete_perm(acl_permset_t permset_d,acl_perm_t perm)101 acl_delete_perm(acl_permset_t permset_d, acl_perm_t perm)
102 {
103 
104 	if (permset_d == NULL) {
105 		errno = EINVAL;
106 		return (-1);
107 	}
108 
109 	if (_perm_is_invalid(perm))
110 		return (-1);
111 
112 	*permset_d &= ~perm;
113 
114 	return (0);
115 }
116 
117 int
acl_get_perm_np(acl_permset_t permset_d,acl_perm_t perm)118 acl_get_perm_np(acl_permset_t permset_d, acl_perm_t perm)
119 {
120 
121 	if (permset_d == NULL) {
122 		errno = EINVAL;
123 		return (-1);
124 	}
125 
126 	if (_perm_is_invalid(perm))
127 		return (-1);
128 
129 	if (*permset_d & perm)
130 		return (1);
131 
132 	return (0);
133 }
134