xref: /freebsd/lib/libc/posix1e/acl_from_text_nfs4.c (revision 59c8e88e72633afbc47a4ace0d2170d00d51f7dc)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2008, 2009 Edward Tomasz Napierała <trasz@FreeBSD.org>
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <stdio.h>
29 #include <stdlib.h>
30 #include <unistd.h>
31 #include <errno.h>
32 #include <assert.h>
33 #include <string.h>
34 #include <pwd.h>
35 #include <grp.h>
36 #include <ctype.h>
37 #include <err.h>
38 #include <sys/syscall.h>
39 #include <sys/types.h>
40 #include <sys/acl.h>
41 
42 #include "acl_support.h"
43 
44 #define MAX_ENTRY_LENGTH 512
45 
46 /*
47  * Parse the tag field of ACL entry passed as "str".  If qualifier
48  * needs to follow, then the variable referenced by "need_qualifier"
49  * is set to 1, otherwise it's set to 0.
50  */
51 static int
52 parse_tag(const char *str, acl_entry_t entry, int *need_qualifier)
53 {
54 
55 	assert(need_qualifier != NULL);
56 	*need_qualifier = 0;
57 
58 	if (strcmp(str, "owner@") == 0)
59 		return (acl_set_tag_type(entry, ACL_USER_OBJ));
60 	if (strcmp(str, "group@") == 0)
61 		return (acl_set_tag_type(entry, ACL_GROUP_OBJ));
62 	if (strcmp(str, "everyone@") == 0)
63 		return (acl_set_tag_type(entry, ACL_EVERYONE));
64 
65 	*need_qualifier = 1;
66 
67 	if (strcmp(str, "user") == 0 || strcmp(str, "u") == 0)
68 		return (acl_set_tag_type(entry, ACL_USER));
69 	if (strcmp(str, "group") == 0 || strcmp(str, "g") == 0)
70 		return (acl_set_tag_type(entry, ACL_GROUP));
71 
72 	warnx("malformed ACL: invalid \"tag\" field");
73 
74 	return (-1);
75 }
76 
77 /*
78  * Parse the qualifier field of ACL entry passed as "str".
79  * If user or group name cannot be resolved, then the variable
80  * referenced by "need_qualifier" is set to 1; it will be checked
81  * later to figure out whether the appended_id is required.
82  */
83 static int
84 parse_qualifier(char *str, acl_entry_t entry, int *need_qualifier)
85 {
86 	int qualifier_length, error;
87 	uid_t id;
88 	acl_tag_t tag;
89 
90 	assert(need_qualifier != NULL);
91 	*need_qualifier = 0;
92 
93 	qualifier_length = strlen(str);
94 
95 	if (qualifier_length == 0) {
96 		warnx("malformed ACL: empty \"qualifier\" field");
97 		return (-1);
98 	}
99 
100 	error = acl_get_tag_type(entry, &tag);
101 	if (error)
102 		return (error);
103 
104 	error = _acl_name_to_id(tag, str, &id);
105 	if (error) {
106 		*need_qualifier = 1;
107 		return (0);
108 	}
109 
110 	return (acl_set_qualifier(entry, &id));
111 }
112 
113 static int
114 parse_access_mask(char *str, acl_entry_t entry)
115 {
116 	int error;
117 	acl_perm_t perm;
118 
119 	error = _nfs4_parse_access_mask(str, &perm);
120 	if (error)
121 		return (error);
122 
123 	error = acl_set_permset(entry, &perm);
124 
125 	return (error);
126 }
127 
128 static int
129 parse_flags(char *str, acl_entry_t entry)
130 {
131 	int error;
132 	acl_flag_t flags;
133 
134 	error = _nfs4_parse_flags(str, &flags);
135 	if (error)
136 		return (error);
137 
138 	error = acl_set_flagset_np(entry, &flags);
139 
140 	return (error);
141 }
142 
143 static int
144 parse_entry_type(const char *str, acl_entry_t entry)
145 {
146 
147 	if (strcmp(str, "allow") == 0)
148 		return (acl_set_entry_type_np(entry, ACL_ENTRY_TYPE_ALLOW));
149 	if (strcmp(str, "deny") == 0)
150 		return (acl_set_entry_type_np(entry, ACL_ENTRY_TYPE_DENY));
151 	if (strcmp(str, "audit") == 0)
152 		return (acl_set_entry_type_np(entry, ACL_ENTRY_TYPE_AUDIT));
153 	if (strcmp(str, "alarm") == 0)
154 		return (acl_set_entry_type_np(entry, ACL_ENTRY_TYPE_ALARM));
155 
156 	warnx("malformed ACL: invalid \"type\" field");
157 
158 	return (-1);
159 }
160 
161 static int
162 parse_appended_id(char *str, acl_entry_t entry)
163 {
164 	int qualifier_length;
165 	char *end;
166 	id_t id;
167 
168 	qualifier_length = strlen(str);
169 	if (qualifier_length == 0) {
170 		warnx("malformed ACL: \"appended id\" field present, "
171 	           "but empty");
172 		return (-1);
173 	}
174 
175 	id = strtod(str, &end);
176 	if (end - str != qualifier_length) {
177 		warnx("malformed ACL: appended id is not a number");
178 		return (-1);
179 	}
180 
181 	return (acl_set_qualifier(entry, &id));
182 }
183 
184 static int
185 number_of_colons(const char *str)
186 {
187 	int count = 0;
188 
189 	while (*str != '\0') {
190 		if (*str == ':')
191 			count++;
192 
193 		str++;
194 	}
195 
196 	return (count);
197 }
198 
199 int
200 _nfs4_acl_entry_from_text(acl_t aclp, char *str)
201 {
202 	int error, need_qualifier;
203 	acl_entry_t entry;
204 	char *field, *qualifier_field;
205 
206 	error = acl_create_entry(&aclp, &entry);
207 	if (error)
208 		return (error);
209 
210 	assert(_entry_brand(entry) == ACL_BRAND_NFS4);
211 
212 	if (str == NULL)
213 		goto truncated_entry;
214 	field = strsep(&str, ":");
215 
216 	field = string_skip_whitespace(field);
217 	if ((*field == '\0') && (!str)) {
218 		/*
219 		 * Is an entirely comment line, skip to next
220 		 * comma.
221 		 */
222 		return (0);
223 	}
224 
225 	error = parse_tag(field, entry, &need_qualifier);
226 	if (error)
227 		goto malformed_field;
228 
229 	if (need_qualifier) {
230 		if (str == NULL)
231 			goto truncated_entry;
232 		qualifier_field = field = strsep(&str, ":");
233 		error = parse_qualifier(field, entry, &need_qualifier);
234 		if (error)
235 			goto malformed_field;
236 	}
237 
238 	if (str == NULL)
239 		goto truncated_entry;
240 	field = strsep(&str, ":");
241 	error = parse_access_mask(field, entry);
242 	if (error)
243 		goto malformed_field;
244 
245 	if (str == NULL)
246 		goto truncated_entry;
247 	/* Do we have "flags" field? */
248 	if (number_of_colons(str) > 0) {
249 		field = strsep(&str, ":");
250 		error = parse_flags(field, entry);
251 		if (error)
252 			goto malformed_field;
253 	}
254 
255 	if (str == NULL)
256 		goto truncated_entry;
257 	field = strsep(&str, ":");
258 	error = parse_entry_type(field, entry);
259 	if (error)
260 		goto malformed_field;
261 
262 	if (need_qualifier) {
263 		if (str == NULL) {
264 			warnx("malformed ACL: unknown user or group name "
265 			    "\"%s\"", qualifier_field);
266 			goto truncated_entry;
267 		}
268 
269 		error = parse_appended_id(str, entry);
270 		if (error)
271 			goto malformed_field;
272 	}
273 
274 	return (0);
275 
276 truncated_entry:
277 malformed_field:
278 	acl_delete_entry(aclp, entry);
279 	errno = EINVAL;
280 	return (-1);
281 }
282