xref: /freebsd/bin/setfacl/merge.c (revision c11e094d96120a2e0e726ed9705ae0ec08db49b6)
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  * $FreeBSD$
27  */
28 
29 #include <sys/types.h>
30 #include <sys/acl.h>
31 #include <sys/stat.h>
32 
33 #include <err.h>
34 #include <stdio.h>
35 
36 #include "setfacl.h"
37 
38 static int merge_user_group(acl_entry_t *entry, acl_entry_t *entry_new);
39 
40 static int
41 merge_user_group(acl_entry_t *entry, acl_entry_t *entry_new)
42 {
43 	acl_permset_t permset;
44 	int have_entry;
45 	uid_t *id, *id_new;
46 
47 	have_entry = 0;
48 
49 	id = acl_get_qualifier(*entry);
50 	if (id == NULL)
51 		err(1, "acl_get_qualifier() failed");
52 	id_new = acl_get_qualifier(*entry_new);
53 	if (id_new == NULL)
54 		err(1, "acl_get_qualifier() failed");
55 	if (*id == *id_new) {
56 		/* any other matches */
57 		if (acl_get_permset(*entry, &permset) == -1)
58 			err(1, "acl_get_permset() failed");
59 		if (acl_set_permset(*entry_new, permset) == -1)
60 			err(1, "acl_set_permset() failed");
61 		have_entry = 1;
62 	}
63 	acl_free(id);
64 	acl_free(id_new);
65 
66 	return (have_entry);
67 }
68 
69 /*
70  * merge an ACL into existing file's ACL
71  */
72 int
73 merge_acl(acl_t acl, acl_t *prev_acl)
74 {
75 	acl_entry_t entry, entry_new;
76 	acl_permset_t permset;
77 	acl_t acl_new;
78 	acl_tag_t tag, tag_new;
79 	int entry_id, entry_id_new, have_entry;
80 
81 	if (acl_type == ACL_TYPE_ACCESS)
82 		acl_new = acl_dup(prev_acl[ACCESS_ACL]);
83 	else
84 		acl_new = acl_dup(prev_acl[DEFAULT_ACL]);
85 	if (acl_new == NULL)
86 		err(1, "acl_dup() failed");
87 
88 	entry_id = ACL_FIRST_ENTRY;
89 
90 	while (acl_get_entry(acl, entry_id, &entry) == 1) {
91 		entry_id = ACL_NEXT_ENTRY;
92 		have_entry = 0;
93 
94 		/* keep track of existing ACL_MASK entries */
95 		if (acl_get_tag_type(entry, &tag) == -1)
96 			err(1, "acl_get_tag_type() failed - invalid ACL entry");
97 		if (tag == ACL_MASK)
98 			have_mask = 1;
99 
100 		/* check against the existing ACL entries */
101 		entry_id_new = ACL_FIRST_ENTRY;
102 		while (have_entry == 0 &&
103 		    acl_get_entry(acl_new, entry_id_new, &entry_new) == 1) {
104 			entry_id_new = ACL_NEXT_ENTRY;
105 
106 			if (acl_get_tag_type(entry, &tag) == -1)
107 				err(1, "acl_get_tag_type() failed");
108 			if (acl_get_tag_type(entry_new, &tag_new) == -1)
109 				err(1, "acl_get_tag_type() failed");
110 			if (tag != tag_new)
111 				continue;
112 
113 			switch(tag) {
114 			case ACL_USER:
115 			case ACL_GROUP:
116 				have_entry = merge_user_group(&entry,
117 				    &entry_new);
118 				if (have_entry == 0)
119 					break;
120 				/* FALLTHROUGH */
121 			case ACL_USER_OBJ:
122 			case ACL_GROUP_OBJ:
123 			case ACL_OTHER:
124 			case ACL_MASK:
125 				if (acl_get_permset(entry, &permset) == -1)
126 					err(1, "acl_get_permset() failed");
127 				if (acl_set_permset(entry_new, permset) == -1)
128 					err(1, "acl_set_permset() failed");
129 				have_entry = 1;
130 				break;
131 			default:
132 				/* should never be here */
133 				errx(1, "Invalid tag type: %i", tag);
134 				break;
135 			}
136 		}
137 
138 		/* if this entry has not been found, it must be new */
139 		if (have_entry == 0) {
140 			if (acl_create_entry(&acl_new, &entry_new) == -1) {
141 				acl_free(acl_new);
142 				return (-1);
143 			}
144 			if (acl_copy_entry(entry_new, entry) == -1)
145 				err(1, "acl_copy_entry() failed");
146 		}
147 	}
148 
149 	if (acl_type == ACL_TYPE_ACCESS) {
150 		acl_free(prev_acl[ACCESS_ACL]);
151 		prev_acl[ACCESS_ACL] = acl_new;
152 	} else {
153 		acl_free(prev_acl[DEFAULT_ACL]);
154 		prev_acl[DEFAULT_ACL] = acl_new;
155 	}
156 
157 	return (0);
158 }
159