1/* $NetBSD: getpeereid.c,v 1.4 2021/08/08 20:54:48 nia Exp $ */
2
3/*-
4 * Copyright (c) 2007 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Arne H. Juul.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32#include <sys/cdefs.h>
33#if defined(LIBC_SCCS) && !defined(lint)
34__RCSID("$NetBSD: getpeereid.c,v 1.4 2021/08/08 20:54:48 nia Exp $");
35#endif /* LIBC_SCCS and not lint */
36
37#include <sys/types.h>
38#include <sys/un.h>
39#include <sys/socket.h>
40#include <unistd.h>
41#include <errno.h>
42
43
44int
45getpeereid(int s, uid_t *euid, gid_t *egid)
46{
47	struct unpcbid cred;
48	struct sockaddr_storage ss;
49	socklen_t len;
50
51	len = sizeof(ss);
52	if (getsockname(s, (void *)&ss, &len) == -1)
53		return -1;
54	if (ss.ss_family != AF_LOCAL) {
55		errno = EOPNOTSUPP;
56		return -1;
57	}
58
59	len = sizeof(cred);
60	if (getsockopt(s, SOL_LOCAL, LOCAL_PEEREID, &cred, &len) == -1)
61		return -1;
62
63	if (euid != NULL)
64		*euid = cred.unp_euid;
65	if (egid != NULL)
66		*egid = cred.unp_egid;
67	return 0;
68}
69