xref: /freebsd/lib/libc/posix1e/acl_perm.c (revision 1670a1c2a47d10ecccd001970b859caf93cd3b6e)
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 AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/types.h>
31 #include "namespace.h"
32 #include <sys/acl.h>
33 #include "un-namespace.h"
34 
35 #include <errno.h>
36 #include <string.h>
37 
38 static int
39 _perm_is_invalid(acl_perm_t perm)
40 {
41 
42 	/* Check if more than a single bit is set. */
43 	if ((perm & -perm) == perm &&
44 	    (perm & (ACL_POSIX1E_BITS | ACL_NFS4_PERM_BITS)) == perm)
45 		return (0);
46 
47 	errno = EINVAL;
48 
49 	return (1);
50 }
51 
52 /*
53  * acl_add_perm() (23.4.1): add the permission contained in perm to the
54  * permission set permset_d
55  */
56 int
57 acl_add_perm(acl_permset_t permset_d, acl_perm_t perm)
58 {
59 
60 	if (permset_d == NULL) {
61 		errno = EINVAL;
62 		return (-1);
63 	}
64 
65 	if (_perm_is_invalid(perm))
66 		return (-1);
67 
68 	*permset_d |= perm;
69 
70 	return (0);
71 }
72 
73 /*
74  * acl_clear_perms() (23.4.3): clear all permisions from the permission
75  * set permset_d
76  */
77 int
78 acl_clear_perms(acl_permset_t permset_d)
79 {
80 
81 	if (permset_d == NULL) {
82 		errno = EINVAL;
83 		return (-1);
84 	}
85 
86 	*permset_d = ACL_PERM_NONE;
87 
88 	return (0);
89 }
90 
91 /*
92  * acl_delete_perm() (23.4.10): remove the permission in perm from the
93  * permission set permset_d
94  */
95 int
96 acl_delete_perm(acl_permset_t permset_d, acl_perm_t perm)
97 {
98 
99 	if (permset_d == NULL) {
100 		errno = EINVAL;
101 		return (-1);
102 	}
103 
104 	if (_perm_is_invalid(perm))
105 		return (-1);
106 
107 	*permset_d &= ~perm;
108 
109 	return (0);
110 }
111 
112 int
113 acl_get_perm_np(acl_permset_t permset_d, acl_perm_t perm)
114 {
115 
116 	if (permset_d == NULL) {
117 		errno = EINVAL;
118 		return (-1);
119 	}
120 
121 	if (_perm_is_invalid(perm))
122 		return (-1);
123 
124 	if (*permset_d & perm)
125 		return (1);
126 
127 	return (0);
128 }
129