xref: /netbsd-src/lib/libc/net/getpeereid.c (revision 213aa76def5f7e6d8b6925a59d5bc8221df842d9)
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 
44 int
getpeereid(int s,uid_t * euid,gid_t * egid)45 getpeereid(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