xref: /freebsd/lib/libc/posix1e/acl_to_text_nfs4.c (revision 3157ba21)
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 <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 static int
47 format_who(char *str, size_t size, const acl_entry_t entry, int numeric)
48 {
49 	int error;
50 	acl_tag_t tag;
51 	struct passwd *pwd;
52 	struct group *grp;
53 	uid_t *id;
54 
55 	error = acl_get_tag_type(entry, &tag);
56 	if (error)
57 		return (error);
58 
59 	switch (tag) {
60 	case ACL_USER_OBJ:
61 		snprintf(str, size, "owner@");
62 		break;
63 
64 	case ACL_USER:
65 		id = (uid_t *)acl_get_qualifier(entry);
66 		if (id == NULL)
67 			return (-1);
68 		/* XXX: Thread-unsafe. */
69 		if (!numeric)
70 			pwd = getpwuid(*id);
71 		else
72 			pwd = NULL;
73 		if (pwd == NULL)
74 			snprintf(str, size, "user:%d", (unsigned int)*id);
75 		else
76 			snprintf(str, size, "user:%s", pwd->pw_name);
77 		break;
78 
79 	case ACL_GROUP_OBJ:
80 		snprintf(str, size, "group@");
81 		break;
82 
83 	case ACL_GROUP:
84 		id = (uid_t *)acl_get_qualifier(entry);
85 		if (id == NULL)
86 			return (-1);
87 		/* XXX: Thread-unsafe. */
88 		if (!numeric)
89 			grp = getgrgid(*id);
90 		else
91 			grp = NULL;
92 		if (grp == NULL)
93 			snprintf(str, size, "group:%d", (unsigned int)*id);
94 		else
95 			snprintf(str, size, "group:%s", grp->gr_name);
96 		break;
97 
98 	case ACL_EVERYONE:
99 		snprintf(str, size, "everyone@");
100 		break;
101 
102 	default:
103 		return (-1);
104 	}
105 
106 	return (0);
107 }
108 
109 static int
110 format_entry_type(char *str, size_t size, const acl_entry_t entry)
111 {
112 	int error;
113 	acl_entry_type_t entry_type;
114 
115 	error = acl_get_entry_type_np(entry, &entry_type);
116 	if (error)
117 		return (error);
118 
119 	switch (entry_type) {
120 	case ACL_ENTRY_TYPE_ALLOW:
121 		snprintf(str, size, "allow");
122 		break;
123 	case ACL_ENTRY_TYPE_DENY:
124 		snprintf(str, size, "deny");
125 		break;
126 	case ACL_ENTRY_TYPE_AUDIT:
127 		snprintf(str, size, "audit");
128 		break;
129 	case ACL_ENTRY_TYPE_ALARM:
130 		snprintf(str, size, "alarm");
131 		break;
132 	default:
133 		return (-1);
134 	}
135 
136 	return (0);
137 }
138 
139 static int
140 format_additional_id(char *str, size_t size, const acl_entry_t entry)
141 {
142 	int error;
143 	acl_tag_t tag;
144 	uid_t *id;
145 
146 	error = acl_get_tag_type(entry, &tag);
147 	if (error)
148 		return (error);
149 
150 	switch (tag) {
151 	case ACL_USER_OBJ:
152 	case ACL_GROUP_OBJ:
153 	case ACL_EVERYONE:
154 		str[0] = '\0';
155 		break;
156 
157 	default:
158 		id = (uid_t *)acl_get_qualifier(entry);
159 		if (id == NULL)
160 			return (-1);
161 		snprintf(str, size, ":%d", (unsigned int)*id);
162 	}
163 
164 	return (0);
165 }
166 
167 static int
168 format_entry(char *str, size_t size, const acl_entry_t entry, int flags)
169 {
170 	size_t off = 0, min_who_field_length = 18;
171 	acl_permset_t permset;
172 	acl_flagset_t flagset;
173 	int error, len;
174 	char buf[MAX_ENTRY_LENGTH + 1];
175 
176 	assert(_entry_brand(entry) == ACL_BRAND_NFS4);
177 
178 	error = acl_get_flagset_np(entry, &flagset);
179 	if (error)
180 		return (error);
181 
182 	error = acl_get_permset(entry, &permset);
183 	if (error)
184 		return (error);
185 
186 	error = format_who(buf, sizeof(buf), entry,
187 	    flags & ACL_TEXT_NUMERIC_IDS);
188 	if (error)
189 		return (error);
190 	len = strlen(buf);
191 	if (len < min_who_field_length)
192 		len = min_who_field_length;
193 	off += snprintf(str + off, size - off, "%*s:", len, buf);
194 
195 	error = _nfs4_format_access_mask(buf, sizeof(buf), *permset,
196 	    flags & ACL_TEXT_VERBOSE);
197 	if (error)
198 		return (error);
199 	off += snprintf(str + off, size - off, "%s:", buf);
200 
201 	error = _nfs4_format_flags(buf, sizeof(buf), *flagset,
202 	    flags & ACL_TEXT_VERBOSE);
203 	if (error)
204 		return (error);
205 	off += snprintf(str + off, size - off, "%s:", buf);
206 
207 	error = format_entry_type(buf, sizeof(buf), entry);
208 	if (error)
209 		return (error);
210 	off += snprintf(str + off, size - off, "%s", buf);
211 
212 	if (flags & ACL_TEXT_APPEND_ID) {
213 		error = format_additional_id(buf, sizeof(buf), entry);
214 		if (error)
215 			return (error);
216 		off += snprintf(str + off, size - off, "%s", buf);
217 	}
218 
219 	off += snprintf(str + off, size - off, "\n");
220 
221 	/* Make sure we didn't truncate anything. */
222 	assert (off < size);
223 
224 	return (0);
225 }
226 
227 char *
228 _nfs4_acl_to_text_np(const acl_t aclp, ssize_t *len_p, int flags)
229 {
230 	int error, off = 0, size, entry_id = ACL_FIRST_ENTRY;
231 	char *str;
232 	acl_entry_t entry;
233 
234 	if (aclp->ats_acl.acl_cnt == 0)
235 		return strdup("");
236 
237 	size = aclp->ats_acl.acl_cnt * MAX_ENTRY_LENGTH;
238 	str = malloc(size);
239 	if (str == NULL)
240 		return (NULL);
241 
242 	while (acl_get_entry(aclp, entry_id, &entry) == 1) {
243 		entry_id = ACL_NEXT_ENTRY;
244 
245 		assert(off < size);
246 
247 		error = format_entry(str + off, size - off, entry, flags);
248 		if (error) {
249 			free(str);
250 			errno = EINVAL;
251 			return (NULL);
252 		}
253 
254 		off = strlen(str);
255 	}
256 
257 	assert(off < size);
258 	str[off] = '\0';
259 
260 	if (len_p != NULL)
261 		*len_p = off;
262 
263 	return (str);
264 }
265