xref: /freebsd/lib/libc/posix1e/acl_equiv_mode_np.c (revision 02e9120893770924227138ba49df1edb3896112a)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2021 Gleb Popov
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 THE 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  * acl_equiv_mode_np: Check if an ACL can be represented as a mode_t.
30  */
31 
32 #include <sys/types.h>
33 #include <sys/param.h>
34 #include <sys/errno.h>
35 #include <sys/stat.h>
36 #include <sys/acl.h>
37 
38 #include "acl_support.h"
39 
40 int
41 acl_equiv_mode_np(acl_t acl, mode_t *mode_p)
42 {
43 	mode_t ret_mode = 0;
44 
45 	if (acl == NULL) {
46 		errno = EINVAL;
47 		return (-1);
48 	}
49 
50 	/* Linux returns 0 for ACL returned by acl_init() */
51 	if (_acl_brand(acl) == ACL_BRAND_UNKNOWN && acl->ats_acl.acl_cnt == 0)
52 		goto done;
53 
54 	// TODO: Do we want to handle ACL_BRAND_NFS4 in this function? */
55 	if (_acl_brand(acl) != ACL_BRAND_POSIX)
56 		return (1);
57 
58 	for (int cur_entry = 0; cur_entry < acl->ats_acl.acl_cnt; cur_entry++) {
59 		acl_entry_t entry = &acl->ats_acl.acl_entry[cur_entry];
60 
61 		if ((entry->ae_perm & ACL_PERM_BITS) != entry->ae_perm)
62 			return (1);
63 
64 		switch (entry->ae_tag) {
65 		case ACL_USER_OBJ:
66 			if (entry->ae_perm & ACL_READ)
67 				ret_mode |= S_IRUSR;
68 			if (entry->ae_perm & ACL_WRITE)
69 				ret_mode |= S_IWUSR;
70 			if (entry->ae_perm & ACL_EXECUTE)
71 				ret_mode |= S_IXUSR;
72 			break;
73 		case ACL_GROUP_OBJ:
74 			if (entry->ae_perm & ACL_READ)
75 				ret_mode |= S_IRGRP;
76 			if (entry->ae_perm & ACL_WRITE)
77 				ret_mode |= S_IWGRP;
78 			if (entry->ae_perm & ACL_EXECUTE)
79 				ret_mode |= S_IXGRP;
80 			break;
81 		case ACL_OTHER:
82 			if (entry->ae_perm & ACL_READ)
83 				ret_mode |= S_IROTH;
84 			if (entry->ae_perm & ACL_WRITE)
85 				ret_mode |= S_IWOTH;
86 			if (entry->ae_perm & ACL_EXECUTE)
87 				ret_mode |= S_IXOTH;
88 			break;
89 		default:
90 			return (1);
91 		}
92 	}
93 
94 done:
95 	if (mode_p != NULL)
96 		*mode_p = ret_mode;
97 
98 	return (0);
99 }
100