NetBSD/sys/kern/sysv_ipc.c

96 lines
3.0 KiB
C

/* $NetBSD: sysv_ipc.c,v 1.14 1998/09/12 17:20:03 christos Exp $ */
/*-
* Copyright (c) 1998 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Charles M. Hannum.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/proc.h>
#include <sys/ipc.h>
#include <sys/systm.h>
#include <sys/mount.h>
#include <sys/vnode.h>
#include <sys/stat.h>
/*
* Check for ipc permission
*/
int
ipcperm(cred, perm, mode)
struct ucred *cred;
struct ipc_perm *perm;
int mode;
{
mode_t mask;
if (cred->cr_uid == 0)
return (0);
if (mode == IPC_M) {
if (cred->cr_uid == perm->uid ||
cred->cr_uid == perm->cuid)
return (0);
return (EPERM);
}
mask = 0;
if (cred->cr_uid == perm->uid ||
cred->cr_uid == perm->cuid) {
if (mode & IPC_R)
mask |= S_IRUSR;
if (mode & IPC_W)
mask |= S_IWUSR;
return ((perm->mode & mask) == mask ? 0 : EACCES);
}
if (cred->cr_gid == perm->gid || groupmember(perm->gid, cred) ||
cred->cr_gid == perm->cgid || groupmember(perm->cgid, cred)) {
if (mode & IPC_R)
mask |= S_IRGRP;
if (mode & IPC_W)
mask |= S_IWGRP;
return ((perm->mode & mask) == mask ? 0 : EACCES);
}
if (mode & IPC_R)
mask |= S_IROTH;
if (mode & IPC_W)
mask |= S_IWOTH;
return ((perm->mode & mask) == mask ? 0 : EACCES);
}