xref: /netbsd-src/bin/setfacl/merge.c (revision 9aa2a9c323eb12a08584c70d6ea91d316703d3fe)
1 /*	$NetBSD: merge.c,v 1.1 2020/05/16 18:31:45 christos Exp $	*/
2 
3 /*-
4  * Copyright (c) 2001 Chris D. Faulhaber
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 #include <sys/cdefs.h>
30 #if 0
31 __FBSDID("$FreeBSD: head/bin/setfacl/merge.c 333065 2018-04-27 15:25:24Z emaste $");
32 #else
33 __RCSID("$NetBSD: merge.c,v 1.1 2020/05/16 18:31:45 christos Exp $");
34 #endif
35 
36 #include <sys/types.h>
37 #include <sys/acl.h>
38 #include <sys/stat.h>
39 
40 #include <err.h>
41 #include <stdio.h>
42 
43 #include "setfacl.h"
44 
45 static int merge_user_group(acl_entry_t *entry, acl_entry_t *entry_new,
46     int acl_brand);
47 
48 static int
merge_user_group(acl_entry_t * entry,acl_entry_t * entry_new,int acl_brand)49 merge_user_group(acl_entry_t *entry, acl_entry_t *entry_new, int acl_brand)
50 {
51 	acl_permset_t permset;
52 	acl_entry_type_t entry_type;
53 	acl_flagset_t flagset;
54 	int have_entry;
55 	uid_t *id, *id_new;
56 
57 	have_entry = 0;
58 
59 	id = acl_get_qualifier(*entry);
60 	if (id == NULL)
61 		err(1, "acl_get_qualifier() failed");
62 	id_new = acl_get_qualifier(*entry_new);
63 	if (id_new == NULL)
64 		err(1, "acl_get_qualifier() failed");
65 	if (*id == *id_new) {
66 		/* any other matches */
67 		if (acl_get_permset(*entry, &permset) == -1)
68 			err(1, "acl_get_permset() failed");
69 		if (acl_set_permset(*entry_new, permset) == -1)
70 			err(1, "acl_set_permset() failed");
71 
72 		if (acl_brand == ACL_BRAND_NFS4) {
73 			if (acl_get_entry_type_np(*entry, &entry_type))
74 				err(1, "acl_get_entry_type_np() failed");
75 			if (acl_set_entry_type_np(*entry_new, entry_type))
76 				err(1, "acl_set_entry_type_np() failed");
77 			if (acl_get_flagset_np(*entry, &flagset))
78 				err(1, "acl_get_flagset_np() failed");
79 			if (acl_set_flagset_np(*entry_new, flagset))
80 				err(1, "acl_set_flagset_np() failed");
81 		}
82 
83 		have_entry = 1;
84 	}
85 	acl_free(id);
86 	acl_free(id_new);
87 
88 	return (have_entry);
89 }
90 
91 /*
92  * merge an ACL into existing file's ACL
93  */
94 int
merge_acl(acl_t acl,acl_t * prev_acl,const char * filename)95 merge_acl(acl_t acl, acl_t *prev_acl, const char *filename)
96 {
97 	acl_entry_t entry, entry_new;
98 	acl_permset_t permset;
99 	acl_t acl_new;
100 	acl_tag_t tag, tag_new;
101 	acl_entry_type_t entry_type, entry_type_new;
102 	acl_flagset_t flagset;
103 	int entry_id, entry_id_new, have_entry, had_entry, entry_number = 0;
104 	int acl_brand, prev_acl_brand;
105 
106 	acl_get_brand_np(acl, &acl_brand);
107 	acl_get_brand_np(*prev_acl, &prev_acl_brand);
108 
109 	if (branding_mismatch(acl_brand, prev_acl_brand)) {
110 		warnx("%s: branding mismatch; existing ACL is %s, "
111 		    "entry to be merged is %s", filename,
112 		    brand_name(prev_acl_brand), brand_name(acl_brand));
113 		return (-1);
114 	}
115 
116 	acl_new = acl_dup(*prev_acl);
117 	if (acl_new == NULL)
118 		err(1, "%s: acl_dup() failed", filename);
119 
120 	entry_id = ACL_FIRST_ENTRY;
121 
122 	while (acl_get_entry(acl, entry_id, &entry) == 1) {
123 		entry_id = ACL_NEXT_ENTRY;
124 		have_entry = 0;
125 		had_entry = 0;
126 
127 		/* keep track of existing ACL_MASK entries */
128 		if (acl_get_tag_type(entry, &tag) == -1)
129 			err(1, "%s: acl_get_tag_type() failed - "
130 			    "invalid ACL entry", filename);
131 		if (tag == ACL_MASK)
132 			have_mask = true;
133 
134 		/* check against the existing ACL entries */
135 		entry_id_new = ACL_FIRST_ENTRY;
136 		while (acl_get_entry(acl_new, entry_id_new, &entry_new) == 1) {
137 			entry_id_new = ACL_NEXT_ENTRY;
138 
139 			if (acl_get_tag_type(entry, &tag) == -1)
140 				err(1, "%s: acl_get_tag_type() failed",
141 				    filename);
142 			if (acl_get_tag_type(entry_new, &tag_new) == -1)
143 				err(1, "%s: acl_get_tag_type() failed",
144 				    filename);
145 			if (tag != tag_new)
146 				continue;
147 
148 			/*
149 			 * For NFSv4, in addition to "tag" and "id" we also
150 			 * compare "entry_type".
151 			 */
152 			if (acl_brand == ACL_BRAND_NFS4) {
153 				if (acl_get_entry_type_np(entry, &entry_type))
154 					err(1, "%s: acl_get_entry_type_np() "
155 					    "failed", filename);
156 				if (acl_get_entry_type_np(entry_new, &entry_type_new))
157 					err(1, "%s: acl_get_entry_type_np() "
158 					    "failed", filename);
159 				if (entry_type != entry_type_new)
160 					continue;
161 			}
162 
163 			switch(tag) {
164 			case ACL_USER:
165 			case ACL_GROUP:
166 				have_entry = merge_user_group(&entry,
167 				    &entry_new, acl_brand);
168 				if (have_entry == 0)
169 					break;
170 				/* FALLTHROUGH */
171 			case ACL_USER_OBJ:
172 			case ACL_GROUP_OBJ:
173 			case ACL_OTHER:
174 			case ACL_MASK:
175 			case ACL_EVERYONE:
176 				if (acl_get_permset(entry, &permset) == -1)
177 					err(1, "%s: acl_get_permset() failed",
178 					    filename);
179 				if (acl_set_permset(entry_new, permset) == -1)
180 					err(1, "%s: acl_set_permset() failed",
181 					    filename);
182 
183 				if (acl_brand == ACL_BRAND_NFS4) {
184 					if (acl_get_entry_type_np(entry, &entry_type))
185 						err(1, "%s: acl_get_entry_type_np() failed",
186 						    filename);
187 					if (acl_set_entry_type_np(entry_new, entry_type))
188 						err(1, "%s: acl_set_entry_type_np() failed",
189 						    filename);
190 					if (acl_get_flagset_np(entry, &flagset))
191 						err(1, "%s: acl_get_flagset_np() failed",
192 						    filename);
193 					if (acl_set_flagset_np(entry_new, flagset))
194 						err(1, "%s: acl_set_flagset_np() failed",
195 						    filename);
196 				}
197 				had_entry = have_entry = 1;
198 				break;
199 			default:
200 				/* should never be here */
201 				errx(1, "%s: invalid tag type: %i", filename, tag);
202 				break;
203 			}
204 		}
205 
206 		/* if this entry has not been found, it must be new */
207 		if (had_entry == 0) {
208 
209 			/*
210 			 * NFSv4 ACL entries must be prepended to the ACL.
211 			 * Appending them at the end makes no sense, since
212 			 * in most cases they wouldn't even get evaluated.
213 			 */
214 			if (acl_brand == ACL_BRAND_NFS4) {
215 				if (acl_create_entry_np(&acl_new, &entry_new, entry_number) == -1) {
216 					warn("%s: acl_create_entry_np() failed", filename);
217 					acl_free(acl_new);
218 					return (-1);
219 				}
220 				/*
221 				 * Without this increment, adding several
222 				 * entries at once, for example
223 				 * "setfacl -m user:1:r:allow,user:2:r:allow",
224 				 * would make them appear in reverse order.
225 				 */
226 				entry_number++;
227 			} else {
228 				if (acl_create_entry(&acl_new, &entry_new) == -1) {
229 					warn("%s: acl_create_entry() failed", filename);
230 					acl_free(acl_new);
231 					return (-1);
232 				}
233 			}
234 			if (acl_copy_entry(entry_new, entry) == -1)
235 				err(1, "%s: acl_copy_entry() failed", filename);
236 		}
237 	}
238 
239 	acl_free(*prev_acl);
240 	*prev_acl = acl_new;
241 
242 	return (0);
243 }
244 
245 int
add_acl(acl_t acl,uint entry_number,acl_t * prev_acl,const char * filename)246 add_acl(acl_t acl, uint entry_number, acl_t *prev_acl, const char *filename)
247 {
248 	acl_entry_t entry, entry_new;
249 	acl_t acl_new;
250 	int entry_id, acl_brand, prev_acl_brand;
251 
252 	acl_get_brand_np(acl, &acl_brand);
253 	acl_get_brand_np(*prev_acl, &prev_acl_brand);
254 
255 	if (prev_acl_brand != ACL_BRAND_NFS4) {
256 		warnx("%s: the '-a' option is only applicable to NFSv4 ACLs",
257 		    filename);
258 		return (-1);
259 	}
260 
261 	if (branding_mismatch(acl_brand, ACL_BRAND_NFS4)) {
262 		warnx("%s: branding mismatch; existing ACL is NFSv4, "
263 		    "entry to be added is %s", filename,
264 		    brand_name(acl_brand));
265 		return (-1);
266 	}
267 
268 	acl_new = acl_dup(*prev_acl);
269 	if (acl_new == NULL)
270 		err(1, "%s: acl_dup() failed", filename);
271 
272 	entry_id = ACL_FIRST_ENTRY;
273 
274 	while (acl_get_entry(acl, entry_id, &entry) == 1) {
275 		entry_id = ACL_NEXT_ENTRY;
276 
277 		if (acl_create_entry_np(&acl_new, &entry_new, entry_number) == -1) {
278 			warn("%s: acl_create_entry_np() failed", filename);
279 			acl_free(acl_new);
280 			return (-1);
281 		}
282 
283 		/*
284 		 * Without this increment, adding several
285 		 * entries at once, for example
286 		 * "setfacl -m user:1:r:allow,user:2:r:allow",
287 		 * would make them appear in reverse order.
288 		 */
289 		entry_number++;
290 
291 		if (acl_copy_entry(entry_new, entry) == -1)
292 			err(1, "%s: acl_copy_entry() failed", filename);
293 	}
294 
295 	acl_free(*prev_acl);
296 	*prev_acl = acl_new;
297 
298 	return (0);
299 }
300