xref: /freebsd/bin/setfacl/merge.c (revision 123af6ec70016f5556da5972d4d63c7d175c06d3)
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, had_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 		had_entry = 0;
120 
121 		/* keep track of existing ACL_MASK entries */
122 		if (acl_get_tag_type(entry, &tag) == -1)
123 			err(1, "%s: acl_get_tag_type() failed - "
124 			    "invalid ACL entry", filename);
125 		if (tag == ACL_MASK)
126 			have_mask = true;
127 
128 		/* check against the existing ACL entries */
129 		entry_id_new = ACL_FIRST_ENTRY;
130 		while (acl_get_entry(acl_new, entry_id_new, &entry_new) == 1) {
131 			entry_id_new = ACL_NEXT_ENTRY;
132 
133 			if (acl_get_tag_type(entry, &tag) == -1)
134 				err(1, "%s: acl_get_tag_type() failed",
135 				    filename);
136 			if (acl_get_tag_type(entry_new, &tag_new) == -1)
137 				err(1, "%s: acl_get_tag_type() failed",
138 				    filename);
139 			if (tag != tag_new)
140 				continue;
141 
142 			/*
143 			 * For NFSv4, in addition to "tag" and "id" we also
144 			 * compare "entry_type".
145 			 */
146 			if (acl_brand == ACL_BRAND_NFS4) {
147 				if (acl_get_entry_type_np(entry, &entry_type))
148 					err(1, "%s: acl_get_entry_type_np() "
149 					    "failed", filename);
150 				if (acl_get_entry_type_np(entry_new, &entry_type_new))
151 					err(1, "%s: acl_get_entry_type_np() "
152 					    "failed", filename);
153 				if (entry_type != entry_type_new)
154 					continue;
155 			}
156 
157 			switch(tag) {
158 			case ACL_USER:
159 			case ACL_GROUP:
160 				have_entry = merge_user_group(&entry,
161 				    &entry_new, acl_brand);
162 				if (have_entry == 0)
163 					break;
164 				/* FALLTHROUGH */
165 			case ACL_USER_OBJ:
166 			case ACL_GROUP_OBJ:
167 			case ACL_OTHER:
168 			case ACL_MASK:
169 			case ACL_EVERYONE:
170 				if (acl_get_permset(entry, &permset) == -1)
171 					err(1, "%s: acl_get_permset() failed",
172 					    filename);
173 				if (acl_set_permset(entry_new, permset) == -1)
174 					err(1, "%s: acl_set_permset() failed",
175 					    filename);
176 
177 				if (acl_brand == ACL_BRAND_NFS4) {
178 					if (acl_get_entry_type_np(entry, &entry_type))
179 						err(1, "%s: acl_get_entry_type_np() failed",
180 						    filename);
181 					if (acl_set_entry_type_np(entry_new, entry_type))
182 						err(1, "%s: acl_set_entry_type_np() failed",
183 						    filename);
184 					if (acl_get_flagset_np(entry, &flagset))
185 						err(1, "%s: acl_get_flagset_np() failed",
186 						    filename);
187 					if (acl_set_flagset_np(entry_new, flagset))
188 						err(1, "%s: acl_set_flagset_np() failed",
189 						    filename);
190 				}
191 				had_entry = have_entry = 1;
192 				break;
193 			default:
194 				/* should never be here */
195 				errx(1, "%s: invalid tag type: %i", filename, tag);
196 				break;
197 			}
198 		}
199 
200 		/* if this entry has not been found, it must be new */
201 		if (had_entry == 0) {
202 
203 			/*
204 			 * NFSv4 ACL entries must be prepended to the ACL.
205 			 * Appending them at the end makes no sense, since
206 			 * in most cases they wouldn't even get evaluated.
207 			 */
208 			if (acl_brand == ACL_BRAND_NFS4) {
209 				if (acl_create_entry_np(&acl_new, &entry_new, entry_number) == -1) {
210 					warn("%s: acl_create_entry_np() failed", filename);
211 					acl_free(acl_new);
212 					return (-1);
213 				}
214 				/*
215 				 * Without this increment, adding several
216 				 * entries at once, for example
217 				 * "setfacl -m user:1:r:allow,user:2:r:allow",
218 				 * would make them appear in reverse order.
219 				 */
220 				entry_number++;
221 			} else {
222 				if (acl_create_entry(&acl_new, &entry_new) == -1) {
223 					warn("%s: acl_create_entry() failed", filename);
224 					acl_free(acl_new);
225 					return (-1);
226 				}
227 			}
228 			if (acl_copy_entry(entry_new, entry) == -1)
229 				err(1, "%s: acl_copy_entry() failed", filename);
230 		}
231 	}
232 
233 	acl_free(*prev_acl);
234 	*prev_acl = acl_new;
235 
236 	return (0);
237 }
238 
239 int
240 add_acl(acl_t acl, uint entry_number, acl_t *prev_acl, const char *filename)
241 {
242 	acl_entry_t entry, entry_new;
243 	acl_t acl_new;
244 	int entry_id, acl_brand, prev_acl_brand;
245 
246 	acl_get_brand_np(acl, &acl_brand);
247 	acl_get_brand_np(*prev_acl, &prev_acl_brand);
248 
249 	if (prev_acl_brand != ACL_BRAND_NFS4) {
250 		warnx("%s: the '-a' option is only applicable to NFSv4 ACLs",
251 		    filename);
252 		return (-1);
253 	}
254 
255 	if (branding_mismatch(acl_brand, ACL_BRAND_NFS4)) {
256 		warnx("%s: branding mismatch; existing ACL is NFSv4, "
257 		    "entry to be added is %s", filename,
258 		    brand_name(acl_brand));
259 		return (-1);
260 	}
261 
262 	acl_new = acl_dup(*prev_acl);
263 	if (acl_new == NULL)
264 		err(1, "%s: acl_dup() failed", filename);
265 
266 	entry_id = ACL_FIRST_ENTRY;
267 
268 	while (acl_get_entry(acl, entry_id, &entry) == 1) {
269 		entry_id = ACL_NEXT_ENTRY;
270 
271 		if (acl_create_entry_np(&acl_new, &entry_new, entry_number) == -1) {
272 			warn("%s: acl_create_entry_np() failed", filename);
273 			acl_free(acl_new);
274 			return (-1);
275 		}
276 
277 		/*
278 		 * Without this increment, adding several
279 		 * entries at once, for example
280 		 * "setfacl -m user:1:r:allow,user:2:r:allow",
281 		 * would make them appear in reverse order.
282 		 */
283 		entry_number++;
284 
285 		if (acl_copy_entry(entry_new, entry) == -1)
286 			err(1, "%s: acl_copy_entry() failed", filename);
287 	}
288 
289 	acl_free(*prev_acl);
290 	*prev_acl = acl_new;
291 
292 	return (0);
293 }
294