xref: /freebsd/lib/libc/posix1e/acl_support_nfs4.c (revision a7623790fb345e6dc986dfd31df0ace115e6f2e4)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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 <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include <stdio.h>
32 #include <stdlib.h>
33 #include <string.h>
34 #include <assert.h>
35 #include <err.h>
36 #include <sys/acl.h>
37 #include "acl_support.h"
38 
39 struct flagnames_struct {
40 	uint32_t	flag;
41 	const char	*name;
42 	char		letter;
43 };
44 
45 struct flagnames_struct a_flags[] =
46     {{ ACL_ENTRY_FILE_INHERIT, "file_inherit", 'f'},
47      { ACL_ENTRY_DIRECTORY_INHERIT, "dir_inherit", 'd'},
48      { ACL_ENTRY_INHERIT_ONLY, "inherit_only", 'i'},
49      { ACL_ENTRY_NO_PROPAGATE_INHERIT, "no_propagate", 'n'},
50      { ACL_ENTRY_SUCCESSFUL_ACCESS, "successfull_access", 'S'},
51      { ACL_ENTRY_FAILED_ACCESS, "failed_access", 'F'},
52      { ACL_ENTRY_INHERITED, "inherited", 'I' },
53      /*
54       * There is no ACE_IDENTIFIER_GROUP here - SunOS does not show it
55       * in the "flags" field.  There is no ACE_OWNER, ACE_GROUP or
56       * ACE_EVERYONE either, for obvious reasons.
57       */
58      { 0, 0, 0}};
59 
60 struct flagnames_struct a_access_masks[] =
61     {{ ACL_READ_DATA, "read_data", 'r'},
62      { ACL_WRITE_DATA, "write_data", 'w'},
63      { ACL_EXECUTE, "execute", 'x'},
64      { ACL_APPEND_DATA, "append_data", 'p'},
65      { ACL_DELETE_CHILD, "delete_child", 'D'},
66      { ACL_DELETE, "delete", 'd'},
67      { ACL_READ_ATTRIBUTES, "read_attributes", 'a'},
68      { ACL_WRITE_ATTRIBUTES, "write_attributes", 'A'},
69      { ACL_READ_NAMED_ATTRS, "read_xattr", 'R'},
70      { ACL_WRITE_NAMED_ATTRS, "write_xattr", 'W'},
71      { ACL_READ_ACL, "read_acl", 'c'},
72      { ACL_WRITE_ACL, "write_acl", 'C'},
73      { ACL_WRITE_OWNER, "write_owner", 'o'},
74      { ACL_SYNCHRONIZE, "synchronize", 's'},
75      { ACL_FULL_SET, "full_set", '\0'},
76      { ACL_MODIFY_SET, "modify_set", '\0'},
77      { ACL_READ_SET, "read_set", '\0'},
78      { ACL_WRITE_SET, "write_set", '\0'},
79      { 0, 0, 0}};
80 
81 static const char *
82 format_flag(uint32_t *var, const struct flagnames_struct *flags)
83 {
84 
85 	for (; flags->name != NULL; flags++) {
86 		if ((flags->flag & *var) == 0)
87 			continue;
88 
89 		*var &= ~flags->flag;
90 		return (flags->name);
91 	}
92 
93 	return (NULL);
94 }
95 
96 static int
97 format_flags_verbose(char *str, size_t size, uint32_t var,
98     const struct flagnames_struct *flags)
99 {
100 	size_t off = 0;
101 	const char *tmp;
102 
103 	while ((tmp = format_flag(&var, flags)) != NULL) {
104 		off += snprintf(str + off, size - off, "%s/", tmp);
105 		assert (off < size);
106 	}
107 
108 	/* If there were any flags added... */
109 	if (off > 0) {
110 		off--;
111 		/* ... then remove the last slash. */
112 		assert(str[off] == '/');
113 	}
114 
115 	str[off] = '\0';
116 
117 	return (0);
118 }
119 
120 static int
121 format_flags_compact(char *str, size_t size, uint32_t var,
122     const struct flagnames_struct *flags)
123 {
124 	size_t i;
125 
126 	for (i = 0; flags[i].letter != '\0'; i++) {
127 		assert(i < size);
128 		if ((flags[i].flag & var) == 0)
129 			str[i] = '-';
130 		else
131 			str[i] = flags[i].letter;
132 	}
133 
134 	str[i] = '\0';
135 
136 	return (0);
137 }
138 
139 static int
140 parse_flags_verbose(const char *strp, uint32_t *var,
141     const struct flagnames_struct *flags, const char *flags_name,
142     int *try_compact)
143 {
144 	int i, found, ever_found = 0;
145 	char *str, *flag;
146 
147 	str = strdup(strp);
148 	*try_compact = 0;
149 	*var = 0;
150 
151 	while (str != NULL) {
152 		flag = strsep(&str, "/:");
153 
154 		found = 0;
155 		for (i = 0; flags[i].name != NULL; i++) {
156 			if (strcmp(flags[i].name, flag) == 0) {
157 				*var |= flags[i].flag;
158 				found = 1;
159 				ever_found = 1;
160 			}
161 		}
162 
163 		if (!found) {
164 			if (ever_found)
165 				warnx("malformed ACL: \"%s\" field contains "
166 				    "invalid flag \"%s\"", flags_name, flag);
167 			else
168 				*try_compact = 1;
169 			free(str);
170 			return (-1);
171 		}
172 	}
173 
174 	free(str);
175 	return (0);
176 }
177 
178 static int
179 parse_flags_compact(const char *str, uint32_t *var,
180     const struct flagnames_struct *flags, const char *flags_name)
181 {
182 	int i, j, found;
183 
184 	*var = 0;
185 
186 	for (i = 0;; i++) {
187 		if (str[i] == '\0')
188 			return (0);
189 
190 		/* Ignore minus signs. */
191 		if (str[i] == '-')
192 			continue;
193 
194 		found = 0;
195 
196 		for (j = 0; flags[j].name != NULL; j++) {
197 			if (flags[j].letter == str[i]) {
198 				*var |= flags[j].flag;
199 				found = 1;
200 				break;
201 			}
202 		}
203 
204 		if (!found) {
205 			warnx("malformed ACL: \"%s\" field contains "
206 			    "invalid flag \"%c\"", flags_name, str[i]);
207 			return (-1);
208 		}
209 	}
210 }
211 
212 int
213 _nfs4_format_flags(char *str, size_t size, acl_flag_t var, int verbose)
214 {
215 
216 	if (verbose)
217 		return (format_flags_verbose(str, size, var, a_flags));
218 
219 	return (format_flags_compact(str, size, var, a_flags));
220 }
221 
222 int
223 _nfs4_format_access_mask(char *str, size_t size, acl_perm_t var, int verbose)
224 {
225 
226 	if (verbose)
227 		return (format_flags_verbose(str, size, var, a_access_masks));
228 
229 	return (format_flags_compact(str, size, var, a_access_masks));
230 }
231 
232 int
233 _nfs4_parse_flags(const char *str, acl_flag_t *flags)
234 {
235 	int error, try_compact;
236 	int tmpflags;
237 
238 	error = parse_flags_verbose(str, &tmpflags, a_flags, "flags", &try_compact);
239 	if (error && try_compact)
240 		error = parse_flags_compact(str, &tmpflags, a_flags, "flags");
241 
242 	*flags = tmpflags;
243 
244 	return (error);
245 }
246 
247 int
248 _nfs4_parse_access_mask(const char *str, acl_perm_t *perms)
249 {
250 	int error, try_compact;
251 	int tmpperms;
252 
253 	error = parse_flags_verbose(str, &tmpperms, a_access_masks,
254 	    "access permissions", &try_compact);
255 	if (error && try_compact)
256 		error = parse_flags_compact(str, &tmpperms,
257 		    a_access_masks, "access permissions");
258 
259 	*perms = tmpperms;
260 
261 	return (error);
262 }
263