xref: /freebsd/bin/setfacl/merge.c (revision 1670a1c2a47d10ecccd001970b859caf93cd3b6e)
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 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 <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     int acl_brand);
41 
42 static int
43 merge_user_group(acl_entry_t *entry, acl_entry_t *entry_new, int acl_brand)
44 {
45 	acl_permset_t permset;
46 	acl_entry_type_t entry_type;
47 	acl_flagset_t flagset;
48 	int have_entry;
49 	uid_t *id, *id_new;
50 
51 	have_entry = 0;
52 
53 	id = acl_get_qualifier(*entry);
54 	if (id == NULL)
55 		err(1, "acl_get_qualifier() failed");
56 	id_new = acl_get_qualifier(*entry_new);
57 	if (id_new == NULL)
58 		err(1, "acl_get_qualifier() failed");
59 	if (*id == *id_new) {
60 		/* any other matches */
61 		if (acl_get_permset(*entry, &permset) == -1)
62 			err(1, "acl_get_permset() failed");
63 		if (acl_set_permset(*entry_new, permset) == -1)
64 			err(1, "acl_set_permset() failed");
65 
66 		if (acl_brand == ACL_BRAND_NFS4) {
67 			if (acl_get_entry_type_np(*entry, &entry_type))
68 				err(1, "acl_get_entry_type_np() failed");
69 			if (acl_set_entry_type_np(*entry_new, entry_type))
70 				err(1, "acl_set_entry_type_np() failed");
71 			if (acl_get_flagset_np(*entry, &flagset))
72 				err(1, "acl_get_flagset_np() failed");
73 			if (acl_set_flagset_np(*entry_new, flagset))
74 				err(1, "acl_set_flagset_np() failed");
75 		}
76 
77 		have_entry = 1;
78 	}
79 	acl_free(id);
80 	acl_free(id_new);
81 
82 	return (have_entry);
83 }
84 
85 /*
86  * merge an ACL into existing file's ACL
87  */
88 int
89 merge_acl(acl_t acl, acl_t *prev_acl, const char *filename)
90 {
91 	acl_entry_t entry, entry_new;
92 	acl_permset_t permset;
93 	acl_t acl_new;
94 	acl_tag_t tag, tag_new;
95 	acl_entry_type_t entry_type, entry_type_new;
96 	acl_flagset_t flagset;
97 	int entry_id, entry_id_new, have_entry, entry_number = 0;
98 	int acl_brand, prev_acl_brand;
99 
100 	acl_get_brand_np(acl, &acl_brand);
101 	acl_get_brand_np(*prev_acl, &prev_acl_brand);
102 
103 	if (branding_mismatch(acl_brand, prev_acl_brand)) {
104 		warnx("%s: branding mismatch; existing ACL is %s, "
105 		    "entry to be merged is %s", filename,
106 		    brand_name(prev_acl_brand), brand_name(acl_brand));
107 		return (-1);
108 	}
109 
110 	acl_new = acl_dup(*prev_acl);
111 	if (acl_new == NULL)
112 		err(1, "%s: acl_dup() failed", filename);
113 
114 	entry_id = ACL_FIRST_ENTRY;
115 
116 	while (acl_get_entry(acl, entry_id, &entry) == 1) {
117 		entry_id = ACL_NEXT_ENTRY;
118 		have_entry = 0;
119 
120 		/* keep track of existing ACL_MASK entries */
121 		if (acl_get_tag_type(entry, &tag) == -1)
122 			err(1, "%s: acl_get_tag_type() failed - "
123 			    "invalid ACL entry", filename);
124 		if (tag == ACL_MASK)
125 			have_mask = 1;
126 
127 		/* check against the existing ACL entries */
128 		entry_id_new = ACL_FIRST_ENTRY;
129 		while (acl_get_entry(acl_new, entry_id_new, &entry_new) == 1) {
130 			entry_id_new = ACL_NEXT_ENTRY;
131 
132 			if (acl_get_tag_type(entry, &tag) == -1)
133 				err(1, "%s: acl_get_tag_type() failed",
134 				    filename);
135 			if (acl_get_tag_type(entry_new, &tag_new) == -1)
136 				err(1, "%s: acl_get_tag_type() failed",
137 				    filename);
138 			if (tag != tag_new)
139 				continue;
140 
141 			/*
142 			 * For NFSv4, in addition to "tag" and "id" we also
143 			 * compare "entry_type".
144 			 */
145 			if (acl_brand == ACL_BRAND_NFS4) {
146 				if (acl_get_entry_type_np(entry, &entry_type))
147 					err(1, "%s: acl_get_entry_type_np() "
148 					    "failed", filename);
149 				if (acl_get_entry_type_np(entry_new, &entry_type_new))
150 					err(1, "%s: acl_get_entry_type_np() "
151 					    "failed", filename);
152 				if (entry_type != entry_type_new)
153 					continue;
154 			}
155 
156 			switch(tag) {
157 			case ACL_USER:
158 			case ACL_GROUP:
159 				have_entry = merge_user_group(&entry,
160 				    &entry_new, acl_brand);
161 				if (have_entry == 0)
162 					break;
163 				/* FALLTHROUGH */
164 			case ACL_USER_OBJ:
165 			case ACL_GROUP_OBJ:
166 			case ACL_OTHER:
167 			case ACL_MASK:
168 			case ACL_EVERYONE:
169 				if (acl_get_permset(entry, &permset) == -1)
170 					err(1, "%s: acl_get_permset() failed",
171 					    filename);
172 				if (acl_set_permset(entry_new, permset) == -1)
173 					err(1, "%s: acl_set_permset() failed",
174 					    filename);
175 
176 				if (acl_brand == ACL_BRAND_NFS4) {
177 					if (acl_get_entry_type_np(entry, &entry_type))
178 						err(1, "%s: acl_get_entry_type_np() failed",
179 						    filename);
180 					if (acl_set_entry_type_np(entry_new, entry_type))
181 						err(1, "%s: acl_set_entry_type_np() failed",
182 						    filename);
183 					if (acl_get_flagset_np(entry, &flagset))
184 						err(1, "%s: acl_get_flagset_np() failed",
185 						    filename);
186 					if (acl_set_flagset_np(entry_new, flagset))
187 						err(1, "%s: acl_set_flagset_np() failed",
188 						    filename);
189 				}
190 				have_entry = 1;
191 				break;
192 			default:
193 				/* should never be here */
194 				errx(1, "%s: invalid tag type: %i", filename, tag);
195 				break;
196 			}
197 		}
198 
199 		/* if this entry has not been found, it must be new */
200 		if (have_entry == 0) {
201 
202 			/*
203 			 * NFSv4 ACL entries must be prepended to the ACL.
204 			 * Appending them at the end makes no sense, since
205 			 * in most cases they wouldn't even get evaluated.
206 			 */
207 			if (acl_brand == ACL_BRAND_NFS4) {
208 				if (acl_create_entry_np(&acl_new, &entry_new, entry_number) == -1) {
209 					warn("%s: acl_create_entry_np() failed", filename);
210 					acl_free(acl_new);
211 					return (-1);
212 				}
213 				/*
214 				 * Without this increment, adding several
215 				 * entries at once, for example
216 				 * "setfacl -m user:1:r:allow,user:2:r:allow",
217 				 * would make them appear in reverse order.
218 				 */
219 				entry_number++;
220 			} else {
221 				if (acl_create_entry(&acl_new, &entry_new) == -1) {
222 					warn("%s: acl_create_entry() failed", filename);
223 					acl_free(acl_new);
224 					return (-1);
225 				}
226 			}
227 			if (acl_copy_entry(entry_new, entry) == -1)
228 				err(1, "%s: acl_copy_entry() failed", filename);
229 		}
230 	}
231 
232 	acl_free(*prev_acl);
233 	*prev_acl = acl_new;
234 
235 	return (0);
236 }
237 
238 int
239 add_acl(acl_t acl, uint entry_number, acl_t *prev_acl, const char *filename)
240 {
241 	acl_entry_t entry, entry_new;
242 	acl_t acl_new;
243 	int entry_id, acl_brand, prev_acl_brand;
244 
245 	acl_get_brand_np(acl, &acl_brand);
246 	acl_get_brand_np(*prev_acl, &prev_acl_brand);
247 
248 	if (prev_acl_brand != ACL_BRAND_NFS4) {
249 		warnx("%s: the '-a' option is only applicable to NFSv4 ACLs",
250 		    filename);
251 		return (-1);
252 	}
253 
254 	if (branding_mismatch(acl_brand, ACL_BRAND_NFS4)) {
255 		warnx("%s: branding mismatch; existing ACL is NFSv4, "
256 		    "entry to be added is %s", filename,
257 		    brand_name(acl_brand));
258 		return (-1);
259 	}
260 
261 	acl_new = acl_dup(*prev_acl);
262 	if (acl_new == NULL)
263 		err(1, "%s: acl_dup() failed", filename);
264 
265 	entry_id = ACL_FIRST_ENTRY;
266 
267 	while (acl_get_entry(acl, entry_id, &entry) == 1) {
268 		entry_id = ACL_NEXT_ENTRY;
269 
270 		if (acl_create_entry_np(&acl_new, &entry_new, entry_number) == -1) {
271 			warn("%s: acl_create_entry_np() failed", filename);
272 			acl_free(acl_new);
273 			return (-1);
274 		}
275 
276 		/*
277 		 * Without this increment, adding several
278 		 * entries at once, for example
279 		 * "setfacl -m user:1:r:allow,user:2:r:allow",
280 		 * would make them appear in reverse order.
281 		 */
282 		entry_number++;
283 
284 		if (acl_copy_entry(entry_new, entry) == -1)
285 			err(1, "%s: acl_copy_entry() failed", filename);
286 	}
287 
288 	acl_free(*prev_acl);
289 	*prev_acl = acl_new;
290 
291 	return (0);
292 }
293