xref: /freebsd/lib/libc/gen/getpeereid.c (revision 8aac90f18aef7c9eea906c3ff9a001ca7b94f375)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2001 Dima Dorfman.
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 #include "namespace.h"
30 #include <sys/param.h>
31 #include <sys/socket.h>
32 #include <sys/ucred.h>
33 #include <sys/un.h>
34 
35 #include <errno.h>
36 #include <unistd.h>
37 #include "un-namespace.h"
38 
39 int
40 getpeereid(int s, uid_t *euid, gid_t *egid)
41 {
42 	struct xucred xuc;
43 	socklen_t xuclen;
44 	int error;
45 
46 	xuclen = sizeof(xuc);
47 	error = _getsockopt(s, SOL_LOCAL, LOCAL_PEERCRED, &xuc, &xuclen);
48 	if (error != 0)
49 		return (error);
50 	if (xuc.cr_version != XUCRED_VERSION) {
51 		errno = EINVAL;
52 		return (-1);
53 	}
54 	*euid = xuc.cr_uid;
55 	*egid = xuc.cr_gid;
56 	return (0);
57 }
58