xref: /freebsd/lib/libc/posix1e/acl_from_text_nfs4.c (revision 0b3105a37d7adcadcb720112fed4dc4e8040be99)
1 /*-
2  * Copyright (c) 2008, 2009 Edward Tomasz Napierała <trasz@FreeBSD.org>
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 <stdio.h>
31 #include <stdlib.h>
32 #include <unistd.h>
33 #include <errno.h>
34 #include <assert.h>
35 #include <string.h>
36 #include <pwd.h>
37 #include <grp.h>
38 #include <ctype.h>
39 #include <err.h>
40 #include <sys/syscall.h>
41 #include <sys/types.h>
42 #include <sys/acl.h>
43 
44 #include "acl_support.h"
45 
46 #define MAX_ENTRY_LENGTH 512
47 
48 /*
49  * Parse the tag field of ACL entry passed as "str".  If qualifier
50  * needs to follow, then the variable referenced by "need_qualifier"
51  * is set to 1, otherwise it's set to 0.
52  */
53 static int
54 parse_tag(const char *str, acl_entry_t entry, int *need_qualifier)
55 {
56 
57 	assert(need_qualifier != NULL);
58 	*need_qualifier = 0;
59 
60 	if (strcmp(str, "owner@") == 0)
61 		return (acl_set_tag_type(entry, ACL_USER_OBJ));
62 	if (strcmp(str, "group@") == 0)
63 		return (acl_set_tag_type(entry, ACL_GROUP_OBJ));
64 	if (strcmp(str, "everyone@") == 0)
65 		return (acl_set_tag_type(entry, ACL_EVERYONE));
66 
67 	*need_qualifier = 1;
68 
69 	if (strcmp(str, "user") == 0 || strcmp(str, "u") == 0)
70 		return (acl_set_tag_type(entry, ACL_USER));
71 	if (strcmp(str, "group") == 0 || strcmp(str, "g") == 0)
72 		return (acl_set_tag_type(entry, ACL_GROUP));
73 
74 	warnx("malformed ACL: invalid \"tag\" field");
75 
76 	return (-1);
77 }
78 
79 /*
80  * Parse the qualifier field of ACL entry passed as "str".
81  * If user or group name cannot be resolved, then the variable
82  * referenced by "need_qualifier" is set to 1; it will be checked
83  * later to figure out whether the appended_id is required.
84  */
85 static int
86 parse_qualifier(char *str, acl_entry_t entry, int *need_qualifier)
87 {
88 	int qualifier_length, error;
89 	uid_t id;
90 	acl_tag_t tag;
91 
92 	assert(need_qualifier != NULL);
93 	*need_qualifier = 0;
94 
95 	qualifier_length = strlen(str);
96 
97 	if (qualifier_length == 0) {
98 		warnx("malformed ACL: empty \"qualifier\" field");
99 		return (-1);
100 	}
101 
102 	error = acl_get_tag_type(entry, &tag);
103 	if (error)
104 		return (error);
105 
106 	error = _acl_name_to_id(tag, str, &id);
107 	if (error) {
108 		*need_qualifier = 1;
109 		return (0);
110 	}
111 
112 	return (acl_set_qualifier(entry, &id));
113 }
114 
115 static int
116 parse_access_mask(char *str, acl_entry_t entry)
117 {
118 	int error;
119 	acl_perm_t perm;
120 
121 	error = _nfs4_parse_access_mask(str, &perm);
122 	if (error)
123 		return (error);
124 
125 	error = acl_set_permset(entry, &perm);
126 
127 	return (error);
128 }
129 
130 static int
131 parse_flags(char *str, acl_entry_t entry)
132 {
133 	int error;
134 	acl_flag_t flags;
135 
136 	error = _nfs4_parse_flags(str, &flags);
137 	if (error)
138 		return (error);
139 
140 	error = acl_set_flagset_np(entry, &flags);
141 
142 	return (error);
143 }
144 
145 static int
146 parse_entry_type(const char *str, acl_entry_t entry)
147 {
148 
149 	if (strcmp(str, "allow") == 0)
150 		return (acl_set_entry_type_np(entry, ACL_ENTRY_TYPE_ALLOW));
151 	if (strcmp(str, "deny") == 0)
152 		return (acl_set_entry_type_np(entry, ACL_ENTRY_TYPE_DENY));
153 	if (strcmp(str, "audit") == 0)
154 		return (acl_set_entry_type_np(entry, ACL_ENTRY_TYPE_AUDIT));
155 	if (strcmp(str, "alarm") == 0)
156 		return (acl_set_entry_type_np(entry, ACL_ENTRY_TYPE_ALARM));
157 
158 	warnx("malformed ACL: invalid \"type\" field");
159 
160 	return (-1);
161 }
162 
163 static int
164 parse_appended_id(char *str, acl_entry_t entry)
165 {
166 	int qualifier_length;
167 	char *end;
168 	id_t id;
169 
170 	qualifier_length = strlen(str);
171 	if (qualifier_length == 0) {
172 		warnx("malformed ACL: \"appended id\" field present, "
173 	           "but empty");
174 		return (-1);
175 	}
176 
177 	id = strtod(str, &end);
178 	if (end - str != qualifier_length) {
179 		warnx("malformed ACL: appended id is not a number");
180 		return (-1);
181 	}
182 
183 	return (acl_set_qualifier(entry, &id));
184 }
185 
186 static int
187 number_of_colons(const char *str)
188 {
189 	int count = 0;
190 
191 	while (*str != '\0') {
192 		if (*str == ':')
193 			count++;
194 
195 		str++;
196 	}
197 
198 	return (count);
199 }
200 
201 int
202 _nfs4_acl_entry_from_text(acl_t aclp, char *str)
203 {
204 	int error, need_qualifier;
205 	acl_entry_t entry;
206 	char *field, *qualifier_field;
207 
208 	error = acl_create_entry(&aclp, &entry);
209 	if (error)
210 		return (error);
211 
212 	assert(_entry_brand(entry) == ACL_BRAND_NFS4);
213 
214 	if (str == NULL)
215 		goto truncated_entry;
216 	field = strsep(&str, ":");
217 
218 	field = string_skip_whitespace(field);
219 	if ((*field == '\0') && (!str)) {
220 		/*
221 		 * Is an entirely comment line, skip to next
222 		 * comma.
223 		 */
224 		return (0);
225 	}
226 
227 	error = parse_tag(field, entry, &need_qualifier);
228 	if (error)
229 		goto malformed_field;
230 
231 	if (need_qualifier) {
232 		if (str == NULL)
233 			goto truncated_entry;
234 		qualifier_field = field = strsep(&str, ":");
235 		error = parse_qualifier(field, entry, &need_qualifier);
236 		if (error)
237 			goto malformed_field;
238 	}
239 
240 	if (str == NULL)
241 		goto truncated_entry;
242 	field = strsep(&str, ":");
243 	error = parse_access_mask(field, entry);
244 	if (error)
245 		goto malformed_field;
246 
247 	if (str == NULL)
248 		goto truncated_entry;
249 	/* Do we have "flags" field? */
250 	if (number_of_colons(str) > 0) {
251 		field = strsep(&str, ":");
252 		error = parse_flags(field, entry);
253 		if (error)
254 			goto malformed_field;
255 	}
256 
257 	if (str == NULL)
258 		goto truncated_entry;
259 	field = strsep(&str, ":");
260 	error = parse_entry_type(field, entry);
261 	if (error)
262 		goto malformed_field;
263 
264 	if (need_qualifier) {
265 		if (str == NULL) {
266 			warnx("malformed ACL: unknown user or group name "
267 			    "\"%s\"", qualifier_field);
268 			goto truncated_entry;
269 		}
270 
271 		error = parse_appended_id(str, entry);
272 		if (error)
273 			goto malformed_field;
274 	}
275 
276 	return (0);
277 
278 truncated_entry:
279 malformed_field:
280 	acl_delete_entry(aclp, entry);
281 	errno = EINVAL;
282 	return (-1);
283 }
284