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/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2006 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
/* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
/* All Rights Reserved */
/*
* Portions of this source code were derived from Berkeley 4.3 BSD
* under license from the Regents of the University of California.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
#include <sys/param.h>
#include <sys/isa_defs.h>
#include <sys/types.h>
#include <sys/sysmacros.h>
#include <sys/cred_impl.h>
#include <sys/systm.h>
#include <sys/errno.h>
#include <sys/pathname.h>
#include <sys/vnode.h>
#include <sys/uio.h>
#include <sys/cmn_err.h>
#include <sys/debug.h>
#include <fs/fs_subr.h>
/*
* Determine accessibility of file.
*/
#define E_OK 010 /* use effective ids */
#define R_OK 004
#define W_OK 002
#define X_OK 001
int
access(char *fname, int fmode)
{
vnode_t *vp;
cred_t *tmpcr;
int error;
int mode;
int eok;
cred_t *cr;
int estale_retry = 0;
if (fmode & ~(E_OK|R_OK|W_OK|X_OK))
return (set_errno(EINVAL));
mode = ((fmode & (R_OK|W_OK|X_OK)) << 6);
cr = CRED();
/* OK to use effective uid/gid, i.e., no need to crdup(CRED())? */
eok = (fmode & E_OK) ||
(cr->cr_uid == cr->cr_ruid && cr->cr_gid == cr->cr_rgid);
if (eok)
tmpcr = cr;
else {
tmpcr = crdup(cr);
tmpcr->cr_uid = cr->cr_ruid;
tmpcr->cr_gid = cr->cr_rgid;
tmpcr->cr_ruid = cr->cr_uid;
tmpcr->cr_rgid = cr->cr_gid;
}
lookup:
if (error = lookupname(fname, UIO_USERSPACE, FOLLOW, NULLVPP, &vp)) {
if ((error == ESTALE) && fs_need_estale_retry(estale_retry++))
goto lookup;
if (!eok)
crfree(tmpcr);
return (set_errno(error));
}
if (mode) {
error = VOP_ACCESS(vp, mode, 0, tmpcr);
if (error) {
if ((error == ESTALE) &&
fs_need_estale_retry(estale_retry++)) {
VN_RELE(vp);
goto lookup;
}
(void) set_errno(error);
}
}
if (!eok)
crfree(tmpcr);
VN_RELE(vp);
return (error);
}
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