NetBSD/sys/kern/sysv_ipc.c
1997-05-08 17:16:15 +00:00

89 lines
2.8 KiB
C

/* $NetBSD: sysv_ipc.c,v 1.12 1997/05/08 17:16:15 mycroft Exp $ */
/*
* Copyright (c) 1995 Charles M. Hannum. All rights reserved.
*
* 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 Charles M. Hannum.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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);
}