freebsd-dev/lib/libc/posix1e/acl_calc_mask.c
Pedro F. Giffuni d915a14ef0 libc: further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using mis-identified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
2017-11-25 17:12:48 +00:00

132 lines
3.7 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2001-2002 Chris D. Faulhaber
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include "namespace.h"
#include <sys/acl.h>
#include "un-namespace.h"
#include <errno.h>
#include <stdio.h>
#include "acl_support.h"
/*
* acl_calc_mask() (23.4.2): calculate and set the permissions
* associated with the ACL_MASK ACL entry. If the ACL already
* contains an ACL_MASK entry, its permissions shall be
* overwritten; if not, one shall be added.
*/
int
acl_calc_mask(acl_t *acl_p)
{
struct acl *acl_int, *acl_int_new;
acl_t acl_new;
int i, mask_mode, mask_num;
/*
* (23.4.2.4) requires acl_p to point to a pointer to a valid ACL.
* Since one of the primary reasons to use this function would be
* to calculate the appropriate mask to obtain a valid ACL, we only
* perform sanity checks here and validate the ACL prior to
* returning.
*/
if (acl_p == NULL || *acl_p == NULL) {
errno = EINVAL;
return (-1);
}
if (!_acl_brand_may_be(*acl_p, ACL_BRAND_POSIX)) {
errno = EINVAL;
return (-1);
}
_acl_brand_as(*acl_p, ACL_BRAND_POSIX);
acl_int = &(*acl_p)->ats_acl;
if ((acl_int->acl_cnt < 3) || (acl_int->acl_cnt > ACL_MAX_ENTRIES)) {
errno = EINVAL;
return (-1);
}
acl_new = acl_dup(*acl_p);
if (acl_new == NULL)
return (-1);
acl_int_new = &acl_new->ats_acl;
mask_mode = 0;
mask_num = -1;
/* gather permissions and find a mask entry */
for (i = 0; i < acl_int_new->acl_cnt; i++) {
switch(acl_int_new->acl_entry[i].ae_tag) {
case ACL_USER:
case ACL_GROUP:
case ACL_GROUP_OBJ:
mask_mode |=
acl_int_new->acl_entry[i].ae_perm & ACL_PERM_BITS;
break;
case ACL_MASK:
mask_num = i;
break;
}
}
/* if a mask entry already exists, overwrite the perms */
if (mask_num != -1)
acl_int_new->acl_entry[mask_num].ae_perm = mask_mode;
else {
/* if no mask exists, check acl_cnt... */
if (acl_int_new->acl_cnt == ACL_MAX_ENTRIES) {
errno = ENOMEM;
acl_free(acl_new);
return (-1);
}
/* ...and add the mask entry */
acl_int_new->acl_entry[acl_int_new->acl_cnt].ae_tag = ACL_MASK;
acl_int_new->acl_entry[acl_int_new->acl_cnt].ae_id =
ACL_UNDEFINED_ID;
acl_int_new->acl_entry[acl_int_new->acl_cnt].ae_perm =
mask_mode;
acl_int_new->acl_cnt++;
}
if (acl_valid(acl_new) == -1) {
errno = EINVAL;
acl_free(acl_new);
return (-1);
}
**acl_p = *acl_new;
acl_free(acl_new);
return (0);
}