Home | History | Annotate | Line # | Download | only in posix1e 
      1 /*-
      2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
      3  *
      4  * Copyright (c) 2008, 2009 Edward Tomasz Napieraa <trasz (at) FreeBSD.org>
      5  * All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  *
     16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
     17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
     20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     26  * SUCH DAMAGE.
     27  */
     28 
     29 #include <sys/cdefs.h>
     30 #if 0
     31 __FBSDID("$FreeBSD: head/lib/libc/posix1e/acl_branding.c 326193 2017-11-25 17:12:48Z pfg $");
     32 #else
     33 __RCSID("$NetBSD: acl_branding.c,v 1.2 2024/01/20 14:52:48 christos Exp $");
     34 #endif
     35 
     36 #include <assert.h>
     37 #include <errno.h>
     38 #include <sys/acl.h>
     39 
     40 #include "acl_support.h"
     41 
     42 /*
     43  * An ugly detail of the implementation - fortunately not visible
     44  * to the API users - is the "branding": libc needs to keep track
     45  * of what "brand" ACL is: NFSv4, POSIX.1e or unknown.  It happens
     46  * automatically - for example, during acl_get_file(3) ACL gets
     47  * branded according to the "type" argument; during acl_set_permset
     48  * ACL, if its brand is unknown it gets branded as NFSv4 if any of the
     49  * NFSv4 permissions that are not valid for POSIX.1e ACL are set etc.
     50  * Branding information is used for printing out the ACL (acl_to_text(3)),
     51  * veryfying acl_set_whatever arguments (checking against setting
     52  * bits that are valid only for NFSv4 in ACL branded as POSIX.1e) etc.
     53  */
     54 
     55 static acl_t
     56 entry2acl(acl_entry_t entry)
     57 {
     58 	acl_t aclp;
     59 
     60 	aclp = (acl_t)(((unsigned long)entry >> _ACL_T_ALIGNMENT_BITS) << _ACL_T_ALIGNMENT_BITS);
     61 
     62 	return (aclp);
     63 }
     64 
     65 /*
     66  * Return brand of an ACL.
     67  */
     68 int
     69 _acl_brand(const acl_t acl)
     70 {
     71 
     72 	return (acl->ats_brand);
     73 }
     74 
     75 int
     76 _entry_brand(const acl_entry_t entry)
     77 {
     78 
     79 	return (_acl_brand(entry2acl(entry)));
     80 }
     81 
     82 /*
     83  * Return 1, iff branding ACL as "brand" is ok.
     84  */
     85 int
     86 _acl_brand_may_be(const acl_t acl, int brand)
     87 {
     88 
     89 	if (_acl_brand(acl) == ACL_BRAND_UNKNOWN)
     90 		return (1);
     91 
     92 	if (_acl_brand(acl) == brand)
     93 		return (1);
     94 
     95 	return (0);
     96 }
     97 
     98 int
     99 _entry_brand_may_be(const acl_entry_t entry, int brand)
    100 {
    101 
    102 	return (_acl_brand_may_be(entry2acl(entry), brand));
    103 }
    104 
    105 /*
    106  * Brand ACL as "brand".
    107  */
    108 void
    109 _acl_brand_as(acl_t acl, int brand)
    110 {
    111 
    112 	assert(_acl_brand_may_be(acl, brand));
    113 
    114 	acl->ats_brand = brand;
    115 }
    116 
    117 void
    118 _entry_brand_as(const acl_entry_t entry, int brand)
    119 {
    120 
    121 	_acl_brand_as(entry2acl(entry), brand);
    122 }
    123 
    124 int
    125 _acl_type_not_valid_for_acl(const acl_t acl, acl_type_t type)
    126 {
    127 
    128 	switch (_acl_brand(acl)) {
    129 	case ACL_BRAND_NFS4:
    130 		if (type == ACL_TYPE_NFS4)
    131 			return (0);
    132 		break;
    133 
    134 	case ACL_BRAND_POSIX:
    135 		if (type == ACL_TYPE_ACCESS || type == ACL_TYPE_DEFAULT)
    136 			return (0);
    137 		break;
    138 
    139 	case ACL_BRAND_UNKNOWN:
    140 		return (0);
    141 	}
    142 
    143 	return (-1);
    144 }
    145 
    146 void
    147 _acl_brand_from_type(acl_t acl, acl_type_t type)
    148 {
    149 
    150 	switch (type) {
    151 	case ACL_TYPE_NFS4:
    152 		_acl_brand_as(acl, ACL_BRAND_NFS4);
    153 		break;
    154 	case ACL_TYPE_ACCESS:
    155 	case ACL_TYPE_DEFAULT:
    156 		_acl_brand_as(acl, ACL_BRAND_POSIX);
    157 		break;
    158 	default:
    159 		/* XXX: What to do here? */
    160 		break;
    161 	}
    162 }
    163 
    164 int
    165 acl_get_brand_np(acl_t acl, int *brand_p)
    166 {
    167 
    168 	if (acl == NULL || brand_p == NULL) {
    169 		errno = EINVAL;
    170 		return (-1);
    171 	}
    172 	*brand_p = _acl_brand(acl);
    173 
    174 	return (0);
    175 }
    176