NetBSD/sys/kern/sysv_ipc.c

103 lines
3.1 KiB
C

/*
* Copyright (c) 1988 University of Utah.
* Copyright (c) 1990 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* the Systems Programming Group of the University of Utah Computer
* Science Department. Originally from University of Wisconsin.
*
* 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 University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University 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 REGENTS 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 REGENTS 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.
*
* from: Utah $Hdr: uipc_shm.c 1.9 89/08/14$
*
* from: @(#)sysv_shm.c 7.15 (Berkeley) 5/13/91
* $Id: sysv_ipc.c,v 1.3 1994/05/12 00:54:58 cgd Exp $
*/
/*
* IPC routines shared by some or all of the SYSV IPC system calls.
*/
#ifndef SYSVIPC
#ifdef SYSVSHM
#define SYSVIPC
#endif
#ifdef SYSVSEM
#define SYSVIPC
#endif
#ifdef SYSVMSG
#define SYSVIPC
#endif
#endif
#ifdef SYSVIPC
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/proc.h>
#include <sys/ipc.h>
/*
* Perform access checking.
*/
ipcaccess(ipc, mode, cred)
register struct ipc_perm *ipc;
int mode;
register struct ucred *cred;
{
register int m;
if (cred->cr_uid == 0)
return(0);
/*
* Access check is based on only one of owner, group, public.
* If not owner, then check group.
* If not a member of the group, then check public access.
*/
mode &= 0700;
m = ipc->mode;
if (cred->cr_uid != ipc->uid && cred->cr_uid != ipc->cuid) {
m <<= 3;
if (!groupmember(ipc->gid, cred) &&
!groupmember(ipc->cgid, cred))
m <<= 3;
}
if ((mode&m) == mode)
return (0);
return (EACCES);
}
#endif /* SYSVSHM */