1/*	$OpenBSD: sysv_ipc.c,v 1.8 2015/03/14 03:38:50 jsg Exp $	*/
2/*	$NetBSD: sysv_ipc.c,v 1.10 1995/06/03 05:53:28 mycroft Exp $	*/
3
4/*
5 * Copyright (c) 1995 Charles M. Hannum.  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 * 3. All advertising materials mentioning features or use of this software
16 *    must display the following acknowledgement:
17 *      This product includes software developed by Charles M. Hannum.
18 * 4. The name of the author may not be used to endorse or promote products
19 *    derived from this software without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 */
32
33#include <sys/param.h>
34#include <sys/ipc.h>
35#include <sys/systm.h>
36#include <sys/mount.h>
37#include <sys/vnode.h>
38
39/*
40 * Check for ipc permission
41 */
42
43int
44ipcperm(struct ucred *cred, struct ipc_perm *perm, int mode)
45{
46
47	if (mode == IPC_M) {
48		if (cred->cr_uid == 0 ||
49		    cred->cr_uid == perm->uid ||
50		    cred->cr_uid == perm->cuid)
51			return (0);
52		return (EPERM);
53	}
54
55	if (vaccess(VNON, perm->mode, perm->uid, perm->gid, mode, cred) == 0 ||
56	    vaccess(VNON, perm->mode, perm->cuid, perm->cgid, mode, cred) == 0)
57		return (0);
58	return (EACCES);
59}
60