1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 1999-2001, 2008 Robert N. M. Watson
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 * Support functionality for the POSIX.1e ACL interface
30 * These calls are intended only to be called within the library.
31 */
32
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD: stable/12/lib/libc/posix1e/acl_id_to_name.c 326193 2017-11-25 17:12:48Z pfg $");
35
36 #include <sys/types.h>
37 #include "namespace.h"
38 #include <sys/acl.h>
39 #include "un-namespace.h"
40 #include <errno.h>
41 #include <grp.h>
42 #include <pwd.h>
43 #include <stdio.h>
44 #include <stdlib.h>
45 #include <string.h>
46 #include <assert.h>
47
48 #include "acl_support.h"
49
50 /*
51 * Given a uid/gid, return a username/groupname for the text form of an ACL.
52 * Note that we truncate user and group names, rather than error out, as
53 * this is consistent with other tools manipulating user and group names.
54 * XXX NOT THREAD SAFE, RELIES ON GETPWUID, GETGRGID
55 * XXX USES *PW* AND *GR* WHICH ARE STATEFUL AND THEREFORE THIS ROUTINE
56 * MAY HAVE SIDE-EFFECTS
57 */
58 int
_posix1e_acl_id_to_name(acl_tag_t tag,uid_t id,ssize_t buf_len,char * buf,int flags)59 _posix1e_acl_id_to_name(acl_tag_t tag, uid_t id, ssize_t buf_len, char *buf,
60 int flags)
61 {
62 struct group *g;
63 struct passwd *p;
64 int i;
65
66 switch(tag) {
67 case ACL_USER:
68 if (flags & ACL_TEXT_NUMERIC_IDS)
69 p = NULL;
70 else
71 p = getpwuid(id);
72 if (!p)
73 i = snprintf(buf, buf_len, "%d", id);
74 else
75 i = snprintf(buf, buf_len, "%s", p->pw_name);
76
77 if (i < 0) {
78 errno = ENOMEM;
79 return (-1);
80 }
81 return (0);
82
83 case ACL_GROUP:
84 if (flags & ACL_TEXT_NUMERIC_IDS)
85 g = NULL;
86 else
87 g = getgrgid(id);
88 if (g == NULL)
89 i = snprintf(buf, buf_len, "%d", id);
90 else
91 i = snprintf(buf, buf_len, "%s", g->gr_name);
92
93 if (i < 0) {
94 errno = ENOMEM;
95 return (-1);
96 }
97 return (0);
98
99 default:
100 return (EINVAL);
101 }
102 }
103