xref: /freebsd/bin/setfacl/merge.c (revision e043f37205ffbde5627ff299ad25cd532f2956f0)
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/types.h>
28 #include <sys/acl.h>
29 #include <sys/stat.h>
30 
31 #include <err.h>
32 
33 #include "setfacl.h"
34 
35 static int merge_user_group(acl_entry_t *entry, acl_entry_t *entry_new,
36     int acl_brand);
37 
38 static int
merge_user_group(acl_entry_t * entry,acl_entry_t * entry_new,int acl_brand)39 merge_user_group(acl_entry_t *entry, acl_entry_t *entry_new, int acl_brand)
40 {
41 	acl_permset_t permset;
42 	acl_entry_type_t entry_type;
43 	acl_flagset_t flagset;
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 
62 		if (acl_brand == ACL_BRAND_NFS4) {
63 			if (acl_get_entry_type_np(*entry, &entry_type))
64 				err(1, "acl_get_entry_type_np() failed");
65 			if (acl_set_entry_type_np(*entry_new, entry_type))
66 				err(1, "acl_set_entry_type_np() failed");
67 			if (acl_get_flagset_np(*entry, &flagset))
68 				err(1, "acl_get_flagset_np() failed");
69 			if (acl_set_flagset_np(*entry_new, flagset))
70 				err(1, "acl_set_flagset_np() failed");
71 		}
72 
73 		have_entry = 1;
74 	}
75 	acl_free(id);
76 	acl_free(id_new);
77 
78 	return (have_entry);
79 }
80 
81 /*
82  * merge an ACL into existing file's ACL
83  */
84 int
merge_acl(acl_t acl,acl_t * prev_acl,const char * filename)85 merge_acl(acl_t acl, acl_t *prev_acl, const char *filename)
86 {
87 	acl_entry_t entry, entry_new;
88 	acl_permset_t permset;
89 	acl_t acl_new;
90 	acl_tag_t tag, tag_new;
91 	acl_entry_type_t entry_type, entry_type_new;
92 	acl_flagset_t flagset;
93 	int entry_id, entry_id_new, have_entry, had_entry, entry_number = 0;
94 	int acl_brand, prev_acl_brand;
95 
96 	acl_get_brand_np(acl, &acl_brand);
97 	acl_get_brand_np(*prev_acl, &prev_acl_brand);
98 
99 	if (branding_mismatch(acl_brand, prev_acl_brand)) {
100 		warnx("%s: branding mismatch; existing ACL is %s, "
101 		    "entry to be merged is %s", filename,
102 		    brand_name(prev_acl_brand), brand_name(acl_brand));
103 		return (-1);
104 	}
105 
106 	acl_new = acl_dup(*prev_acl);
107 	if (acl_new == NULL)
108 		err(1, "%s: acl_dup() failed", filename);
109 
110 	entry_id = ACL_FIRST_ENTRY;
111 
112 	while (acl_get_entry(acl, entry_id, &entry) == 1) {
113 		entry_id = ACL_NEXT_ENTRY;
114 		have_entry = 0;
115 		had_entry = 0;
116 
117 		/* keep track of existing ACL_MASK entries */
118 		if (acl_get_tag_type(entry, &tag) == -1)
119 			err(1, "%s: acl_get_tag_type() failed - "
120 			    "invalid ACL entry", filename);
121 		if (tag == ACL_MASK)
122 			have_mask = true;
123 
124 		/* check against the existing ACL entries */
125 		entry_id_new = ACL_FIRST_ENTRY;
126 		while (acl_get_entry(acl_new, entry_id_new, &entry_new) == 1) {
127 			entry_id_new = ACL_NEXT_ENTRY;
128 
129 			if (acl_get_tag_type(entry, &tag) == -1)
130 				err(1, "%s: acl_get_tag_type() failed",
131 				    filename);
132 			if (acl_get_tag_type(entry_new, &tag_new) == -1)
133 				err(1, "%s: acl_get_tag_type() failed",
134 				    filename);
135 			if (tag != tag_new)
136 				continue;
137 
138 			/*
139 			 * For NFSv4, in addition to "tag" and "id" we also
140 			 * compare "entry_type".
141 			 */
142 			if (acl_brand == ACL_BRAND_NFS4) {
143 				if (acl_get_entry_type_np(entry, &entry_type))
144 					err(1, "%s: acl_get_entry_type_np() "
145 					    "failed", filename);
146 				if (acl_get_entry_type_np(entry_new, &entry_type_new))
147 					err(1, "%s: acl_get_entry_type_np() "
148 					    "failed", filename);
149 				if (entry_type != entry_type_new)
150 					continue;
151 			}
152 
153 			switch(tag) {
154 			case ACL_USER:
155 			case ACL_GROUP:
156 				have_entry = merge_user_group(&entry,
157 				    &entry_new, acl_brand);
158 				if (have_entry == 0)
159 					break;
160 				/* FALLTHROUGH */
161 			case ACL_USER_OBJ:
162 			case ACL_GROUP_OBJ:
163 			case ACL_OTHER:
164 			case ACL_MASK:
165 			case ACL_EVERYONE:
166 				if (acl_get_permset(entry, &permset) == -1)
167 					err(1, "%s: acl_get_permset() failed",
168 					    filename);
169 				if (acl_set_permset(entry_new, permset) == -1)
170 					err(1, "%s: acl_set_permset() failed",
171 					    filename);
172 
173 				if (acl_brand == ACL_BRAND_NFS4) {
174 					if (acl_get_entry_type_np(entry, &entry_type))
175 						err(1, "%s: acl_get_entry_type_np() failed",
176 						    filename);
177 					if (acl_set_entry_type_np(entry_new, entry_type))
178 						err(1, "%s: acl_set_entry_type_np() failed",
179 						    filename);
180 					if (acl_get_flagset_np(entry, &flagset))
181 						err(1, "%s: acl_get_flagset_np() failed",
182 						    filename);
183 					if (acl_set_flagset_np(entry_new, flagset))
184 						err(1, "%s: acl_set_flagset_np() failed",
185 						    filename);
186 				}
187 				had_entry = have_entry = 1;
188 				break;
189 			default:
190 				/* should never be here */
191 				errx(1, "%s: invalid tag type: %i", filename, tag);
192 				break;
193 			}
194 		}
195 
196 		/* if this entry has not been found, it must be new */
197 		if (had_entry == 0) {
198 
199 			/*
200 			 * NFSv4 ACL entries must be prepended to the ACL.
201 			 * Appending them at the end makes no sense, since
202 			 * in most cases they wouldn't even get evaluated.
203 			 */
204 			if (acl_brand == ACL_BRAND_NFS4) {
205 				if (acl_create_entry_np(&acl_new, &entry_new, entry_number) == -1) {
206 					warn("%s: acl_create_entry_np() failed", filename);
207 					acl_free(acl_new);
208 					return (-1);
209 				}
210 				/*
211 				 * Without this increment, adding several
212 				 * entries at once, for example
213 				 * "setfacl -m user:1:r:allow,user:2:r:allow",
214 				 * would make them appear in reverse order.
215 				 */
216 				entry_number++;
217 			} else {
218 				if (acl_create_entry(&acl_new, &entry_new) == -1) {
219 					warn("%s: acl_create_entry() failed", filename);
220 					acl_free(acl_new);
221 					return (-1);
222 				}
223 			}
224 			if (acl_copy_entry(entry_new, entry) == -1)
225 				err(1, "%s: acl_copy_entry() failed", filename);
226 		}
227 	}
228 
229 	acl_free(*prev_acl);
230 	*prev_acl = acl_new;
231 
232 	return (0);
233 }
234 
235 int
add_acl(acl_t acl,uint entry_number,acl_t * prev_acl,const char * filename)236 add_acl(acl_t acl, uint entry_number, acl_t *prev_acl, const char *filename)
237 {
238 	acl_entry_t entry, entry_new;
239 	acl_t acl_new;
240 	int entry_id, acl_brand, prev_acl_brand;
241 
242 	acl_get_brand_np(acl, &acl_brand);
243 	acl_get_brand_np(*prev_acl, &prev_acl_brand);
244 
245 	if (prev_acl_brand != ACL_BRAND_NFS4) {
246 		warnx("%s: the '-a' option is only applicable to NFSv4 ACLs",
247 		    filename);
248 		return (-1);
249 	}
250 
251 	if (branding_mismatch(acl_brand, ACL_BRAND_NFS4)) {
252 		warnx("%s: branding mismatch; existing ACL is NFSv4, "
253 		    "entry to be added is %s", filename,
254 		    brand_name(acl_brand));
255 		return (-1);
256 	}
257 
258 	acl_new = acl_dup(*prev_acl);
259 	if (acl_new == NULL)
260 		err(1, "%s: acl_dup() failed", filename);
261 
262 	entry_id = ACL_FIRST_ENTRY;
263 
264 	while (acl_get_entry(acl, entry_id, &entry) == 1) {
265 		entry_id = ACL_NEXT_ENTRY;
266 
267 		if (acl_create_entry_np(&acl_new, &entry_new, entry_number) == -1) {
268 			warn("%s: acl_create_entry_np() failed", filename);
269 			acl_free(acl_new);
270 			return (-1);
271 		}
272 
273 		/*
274 		 * Without this increment, adding several
275 		 * entries at once, for example
276 		 * "setfacl -m user:1:r:allow,user:2:r:allow",
277 		 * would make them appear in reverse order.
278 		 */
279 		entry_number++;
280 
281 		if (acl_copy_entry(entry_new, entry) == -1)
282 			err(1, "%s: acl_copy_entry() failed", filename);
283 	}
284 
285 	acl_free(*prev_acl);
286 	*prev_acl = acl_new;
287 
288 	return (0);
289 }
290