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 #if 0
35 __FBSDID("$FreeBSD: head/lib/libc/posix1e/acl_id_to_name.c 326193 2017-11-25 17:12:48Z pfg $");
36 #else
37 __RCSID("$NetBSD: acl_id_to_name.c,v 1.1 2020/05/16 18:31:47 christos Exp $");
38 #endif
39
40 #include "namespace.h"
41 #include <sys/types.h>
42 #include <sys/acl.h>
43 #include <errno.h>
44 #include <grp.h>
45 #include <pwd.h>
46 #include <stdio.h>
47 #include <stdlib.h>
48 #include <string.h>
49 #include <assert.h>
50
51 #include "acl_support.h"
52
53 /*
54 * Given a uid/gid, return a username/groupname for the text form of an ACL.
55 * Note that we truncate user and group names, rather than error out, as
56 * this is consistent with other tools manipulating user and group names.
57 * XXX NOT THREAD SAFE, RELIES ON GETPWUID, GETGRGID
58 * XXX USES *PW* AND *GR* WHICH ARE STATEFUL AND THEREFORE THIS ROUTINE
59 * MAY HAVE SIDE-EFFECTS
60 */
61 int
_posix1e_acl_id_to_name(acl_tag_t tag,uid_t id,ssize_t buf_len,char * buf,int flags)62 _posix1e_acl_id_to_name(acl_tag_t tag, uid_t id, ssize_t buf_len, char *buf,
63 int flags)
64 {
65 struct group *g;
66 struct passwd *p;
67 int i;
68
69 switch(tag) {
70 case ACL_USER:
71 if (flags & ACL_TEXT_NUMERIC_IDS)
72 p = NULL;
73 else
74 p = getpwuid(id);
75 if (!p)
76 i = snprintf(buf, buf_len, "%d", id);
77 else
78 i = snprintf(buf, buf_len, "%s", p->pw_name);
79
80 if (i < 0) {
81 errno = ENOMEM;
82 return (-1);
83 }
84 return (0);
85
86 case ACL_GROUP:
87 if (flags & ACL_TEXT_NUMERIC_IDS)
88 g = NULL;
89 else
90 g = getgrgid(id);
91 if (g == NULL)
92 i = snprintf(buf, buf_len, "%d", id);
93 else
94 i = snprintf(buf, buf_len, "%s", g->gr_name);
95
96 if (i < 0) {
97 errno = ENOMEM;
98 return (-1);
99 }
100 return (0);
101
102 default:
103 return (EINVAL);
104 }
105 }
106