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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 (c) 1994, 2010, Oracle and/or its affiliates. All rights reserved.
*/
/* 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.
*/
#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 <sys/file.h>
#include <fs/fs_subr.h>
#include <c2/audit.h>
#include <sys/fcntl.h>
/*
* Determine accessibility of file.
*/
#define E_OK 010 /* use effective ids */
#define R_OK 004
#define W_OK 002
#define X_OK 001
static int
caccess(char *fname, int fmode, vnode_t *startvp)
{
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 (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 = lookupnameatcred(fname, UIO_USERSPACE, FOLLOW, NULLVPP, &vp,
startvp, tmpcr)) {
if ((error == ESTALE) && fs_need_estale_retry(estale_retry++))
goto lookup;
if (!eok)
crfree(tmpcr);
return (error);
}
if (mode) {
error = VOP_ACCESS(vp, mode, 0, tmpcr, NULL);
if (error) {
if ((error == ESTALE) &&
fs_need_estale_retry(estale_retry++)) {
VN_RELE(vp);
goto lookup;
}
}
}
if (!eok)
crfree(tmpcr);
VN_RELE(vp);
return (error);
}
int
faccessat(int fd, char *fname, int fmode, int flag)
{
vnode_t *startvp;
int error;
if ((flag & ~AT_EACCESS) != 0)
return (set_errno(EINVAL));
if (fname == NULL)
return (set_errno(EFAULT));
if ((error = fgetstartvp(fd, fname, &startvp)) != 0)
return (set_errno(error));
if (AU_AUDITING() && startvp != NULL)
audit_setfsat_path(1);
/* Do not allow E_OK unless AT_EACCESS flag is set */
fmode &= ~E_OK;
if (flag & AT_EACCESS)
fmode |= E_OK;
error = caccess(fname, fmode, startvp);
if (startvp != NULL)
VN_RELE(startvp);
if (error)
return (set_errno(error));
return (0);
}
int
access(char *fname, int fmode)
{
return (faccessat(AT_FDCWD, fname, fmode, 0));
}
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