xref: /freebsd/bin/setfacl/merge.c (revision 9ddb49cbe45441fa3f3a10f6dd355e9956480b5f)
1 /*-
2  * Copyright (c) 2001 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("$FreeBSD$");
29 
30 #include <sys/types.h>
31 #include <sys/acl.h>
32 #include <sys/stat.h>
33 
34 #include <err.h>
35 #include <stdio.h>
36 
37 #include "setfacl.h"
38 
39 static int merge_user_group(acl_entry_t *entry, acl_entry_t *entry_new);
40 
41 static int
42 merge_user_group(acl_entry_t *entry, acl_entry_t *entry_new)
43 {
44 	acl_permset_t permset;
45 	int have_entry;
46 	uid_t *id, *id_new;
47 
48 	have_entry = 0;
49 
50 	id = acl_get_qualifier(*entry);
51 	if (id == NULL)
52 		err(1, "acl_get_qualifier() failed");
53 	id_new = acl_get_qualifier(*entry_new);
54 	if (id_new == NULL)
55 		err(1, "acl_get_qualifier() failed");
56 	if (*id == *id_new) {
57 		/* any other matches */
58 		if (acl_get_permset(*entry, &permset) == -1)
59 			err(1, "acl_get_permset() failed");
60 		if (acl_set_permset(*entry_new, permset) == -1)
61 			err(1, "acl_set_permset() failed");
62 		have_entry = 1;
63 	}
64 	acl_free(id);
65 	acl_free(id_new);
66 
67 	return (have_entry);
68 }
69 
70 /*
71  * merge an ACL into existing file's ACL
72  */
73 int
74 merge_acl(acl_t acl, acl_t *prev_acl)
75 {
76 	acl_entry_t entry, entry_new;
77 	acl_permset_t permset;
78 	acl_t acl_new;
79 	acl_tag_t tag, tag_new;
80 	int entry_id, entry_id_new, have_entry;
81 
82 	if (acl_type == ACL_TYPE_ACCESS)
83 		acl_new = acl_dup(prev_acl[ACCESS_ACL]);
84 	else
85 		acl_new = acl_dup(prev_acl[DEFAULT_ACL]);
86 	if (acl_new == NULL)
87 		err(1, "acl_dup() failed");
88 
89 	entry_id = ACL_FIRST_ENTRY;
90 
91 	while (acl_get_entry(acl, entry_id, &entry) == 1) {
92 		entry_id = ACL_NEXT_ENTRY;
93 		have_entry = 0;
94 
95 		/* keep track of existing ACL_MASK entries */
96 		if (acl_get_tag_type(entry, &tag) == -1)
97 			err(1, "acl_get_tag_type() failed - invalid ACL entry");
98 		if (tag == ACL_MASK)
99 			have_mask = 1;
100 
101 		/* check against the existing ACL entries */
102 		entry_id_new = ACL_FIRST_ENTRY;
103 		while (have_entry == 0 &&
104 		    acl_get_entry(acl_new, entry_id_new, &entry_new) == 1) {
105 			entry_id_new = ACL_NEXT_ENTRY;
106 
107 			if (acl_get_tag_type(entry, &tag) == -1)
108 				err(1, "acl_get_tag_type() failed");
109 			if (acl_get_tag_type(entry_new, &tag_new) == -1)
110 				err(1, "acl_get_tag_type() failed");
111 			if (tag != tag_new)
112 				continue;
113 
114 			switch(tag) {
115 			case ACL_USER:
116 			case ACL_GROUP:
117 				have_entry = merge_user_group(&entry,
118 				    &entry_new);
119 				if (have_entry == 0)
120 					break;
121 				/* FALLTHROUGH */
122 			case ACL_USER_OBJ:
123 			case ACL_GROUP_OBJ:
124 			case ACL_OTHER:
125 			case ACL_MASK:
126 				if (acl_get_permset(entry, &permset) == -1)
127 					err(1, "acl_get_permset() failed");
128 				if (acl_set_permset(entry_new, permset) == -1)
129 					err(1, "acl_set_permset() failed");
130 				have_entry = 1;
131 				break;
132 			default:
133 				/* should never be here */
134 				errx(1, "Invalid tag type: %i", tag);
135 				break;
136 			}
137 		}
138 
139 		/* if this entry has not been found, it must be new */
140 		if (have_entry == 0) {
141 			if (acl_create_entry(&acl_new, &entry_new) == -1) {
142 				acl_free(acl_new);
143 				return (-1);
144 			}
145 			if (acl_copy_entry(entry_new, entry) == -1)
146 				err(1, "acl_copy_entry() failed");
147 		}
148 	}
149 
150 	if (acl_type == ACL_TYPE_ACCESS) {
151 		acl_free(prev_acl[ACCESS_ACL]);
152 		prev_acl[ACCESS_ACL] = acl_new;
153 	} else {
154 		acl_free(prev_acl[DEFAULT_ACL]);
155 		prev_acl[DEFAULT_ACL] = acl_new;
156 	}
157 
158 	return (0);
159 }
160