xref: /freebsd/lib/libc/posix1e/acl_support_nfs4.c (revision 8df8b2d3e51d1b816201d8a1fe8bc29fe192e562)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2008, 2009 Edward Tomasz Napierała <trasz@FreeBSD.org>
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 __FBSDID("$FreeBSD$");
31 
32 #include <stdio.h>
33 #include <stdlib.h>
34 #include <string.h>
35 #include <assert.h>
36 #include <err.h>
37 #include <sys/acl.h>
38 #include "acl_support.h"
39 
40 struct flagnames_struct {
41 	uint32_t	flag;
42 	const char	*name;
43 	char		letter;
44 };
45 
46 struct flagnames_struct a_flags[] =
47     {{ ACL_ENTRY_FILE_INHERIT, "file_inherit", 'f'},
48      { ACL_ENTRY_DIRECTORY_INHERIT, "dir_inherit", 'd'},
49      { ACL_ENTRY_INHERIT_ONLY, "inherit_only", 'i'},
50      { ACL_ENTRY_NO_PROPAGATE_INHERIT, "no_propagate", 'n'},
51      { ACL_ENTRY_SUCCESSFUL_ACCESS, "successfull_access", 'S'},
52      { ACL_ENTRY_FAILED_ACCESS, "failed_access", 'F'},
53      { ACL_ENTRY_INHERITED, "inherited", 'I' },
54      /*
55       * There is no ACE_IDENTIFIER_GROUP here - SunOS does not show it
56       * in the "flags" field.  There is no ACE_OWNER, ACE_GROUP or
57       * ACE_EVERYONE either, for obvious reasons.
58       */
59      { 0, 0, 0}};
60 
61 struct flagnames_struct a_access_masks[] =
62     {{ ACL_READ_DATA, "read_data", 'r'},
63      { ACL_WRITE_DATA, "write_data", 'w'},
64      { ACL_EXECUTE, "execute", 'x'},
65      { ACL_APPEND_DATA, "append_data", 'p'},
66      { ACL_DELETE_CHILD, "delete_child", 'D'},
67      { ACL_DELETE, "delete", 'd'},
68      { ACL_READ_ATTRIBUTES, "read_attributes", 'a'},
69      { ACL_WRITE_ATTRIBUTES, "write_attributes", 'A'},
70      { ACL_READ_NAMED_ATTRS, "read_xattr", 'R'},
71      { ACL_WRITE_NAMED_ATTRS, "write_xattr", 'W'},
72      { ACL_READ_ACL, "read_acl", 'c'},
73      { ACL_WRITE_ACL, "write_acl", 'C'},
74      { ACL_WRITE_OWNER, "write_owner", 'o'},
75      { ACL_SYNCHRONIZE, "synchronize", 's'},
76      { ACL_FULL_SET, "full_set", '\0'},
77      { ACL_MODIFY_SET, "modify_set", '\0'},
78      { ACL_READ_SET, "read_set", '\0'},
79      { ACL_WRITE_SET, "write_set", '\0'},
80      { 0, 0, 0}};
81 
82 static const char *
83 format_flag(uint32_t *var, const struct flagnames_struct *flags)
84 {
85 
86 	for (; flags->name != NULL; flags++) {
87 		if ((flags->flag & *var) == 0)
88 			continue;
89 
90 		*var &= ~flags->flag;
91 		return (flags->name);
92 	}
93 
94 	return (NULL);
95 }
96 
97 static int
98 format_flags_verbose(char *str, size_t size, uint32_t var,
99     const struct flagnames_struct *flags)
100 {
101 	size_t off = 0;
102 	const char *tmp;
103 
104 	while ((tmp = format_flag(&var, flags)) != NULL) {
105 		off += snprintf(str + off, size - off, "%s/", tmp);
106 		assert (off < size);
107 	}
108 
109 	/* If there were any flags added... */
110 	if (off > 0) {
111 		off--;
112 		/* ... then remove the last slash. */
113 		assert(str[off] == '/');
114 	}
115 
116 	str[off] = '\0';
117 
118 	return (0);
119 }
120 
121 static int
122 format_flags_compact(char *str, size_t size, uint32_t var,
123     const struct flagnames_struct *flags)
124 {
125 	size_t i;
126 
127 	for (i = 0; flags[i].letter != '\0'; i++) {
128 		assert(i < size);
129 		if ((flags[i].flag & var) == 0)
130 			str[i] = '-';
131 		else
132 			str[i] = flags[i].letter;
133 	}
134 
135 	str[i] = '\0';
136 
137 	return (0);
138 }
139 
140 static int
141 parse_flags_verbose(const char *strp, uint32_t *var,
142     const struct flagnames_struct *flags, const char *flags_name,
143     int *try_compact)
144 {
145 	int i, found, ever_found = 0;
146 	char *str, *flag;
147 
148 	str = strdup(strp);
149 	*try_compact = 0;
150 	*var = 0;
151 
152 	while (str != NULL) {
153 		flag = strsep(&str, "/:");
154 
155 		found = 0;
156 		for (i = 0; flags[i].name != NULL; i++) {
157 			if (strcmp(flags[i].name, flag) == 0) {
158 				*var |= flags[i].flag;
159 				found = 1;
160 				ever_found = 1;
161 			}
162 		}
163 
164 		if (!found) {
165 			if (ever_found)
166 				warnx("malformed ACL: \"%s\" field contains "
167 				    "invalid flag \"%s\"", flags_name, flag);
168 			else
169 				*try_compact = 1;
170 			free(str);
171 			return (-1);
172 		}
173 	}
174 
175 	free(str);
176 	return (0);
177 }
178 
179 static int
180 parse_flags_compact(const char *str, uint32_t *var,
181     const struct flagnames_struct *flags, const char *flags_name)
182 {
183 	int i, j, found;
184 
185 	*var = 0;
186 
187 	for (i = 0;; i++) {
188 		if (str[i] == '\0')
189 			return (0);
190 
191 		/* Ignore minus signs. */
192 		if (str[i] == '-')
193 			continue;
194 
195 		found = 0;
196 
197 		for (j = 0; flags[j].name != NULL; j++) {
198 			if (flags[j].letter == str[i]) {
199 				*var |= flags[j].flag;
200 				found = 1;
201 				break;
202 			}
203 		}
204 
205 		if (!found) {
206 			warnx("malformed ACL: \"%s\" field contains "
207 			    "invalid flag \"%c\"", flags_name, str[i]);
208 			return (-1);
209 		}
210 	}
211 }
212 
213 int
214 _nfs4_format_flags(char *str, size_t size, acl_flag_t var, int verbose)
215 {
216 
217 	if (verbose)
218 		return (format_flags_verbose(str, size, var, a_flags));
219 
220 	return (format_flags_compact(str, size, var, a_flags));
221 }
222 
223 int
224 _nfs4_format_access_mask(char *str, size_t size, acl_perm_t var, int verbose)
225 {
226 
227 	if (verbose)
228 		return (format_flags_verbose(str, size, var, a_access_masks));
229 
230 	return (format_flags_compact(str, size, var, a_access_masks));
231 }
232 
233 int
234 _nfs4_parse_flags(const char *str, acl_flag_t *flags)
235 {
236 	int error, try_compact;
237 	int tmpflags;
238 
239 	error = parse_flags_verbose(str, &tmpflags, a_flags, "flags", &try_compact);
240 	if (error && try_compact)
241 		error = parse_flags_compact(str, &tmpflags, a_flags, "flags");
242 
243 	*flags = tmpflags;
244 
245 	return (error);
246 }
247 
248 int
249 _nfs4_parse_access_mask(const char *str, acl_perm_t *perms)
250 {
251 	int error, try_compact;
252 	int tmpperms;
253 
254 	error = parse_flags_verbose(str, &tmpperms, a_access_masks,
255 	    "access permissions", &try_compact);
256 	if (error && try_compact)
257 		error = parse_flags_compact(str, &tmpperms,
258 		    a_access_masks, "access permissions");
259 
260 	*perms = tmpperms;
261 
262 	return (error);
263 }
264