1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2001-2002 Chris D. Faulhaber
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/types.h>
30#include "namespace.h"
31#include <sys/acl.h>
32#include "un-namespace.h"
33#include <errno.h>
34#include <string.h>
35#include <stdio.h>
36
37#include "acl_support.h"
38
39static int
40_entry_matches(const acl_entry_t a, const acl_entry_t b)
41{
42	/*
43	 * There is a semantical difference here between NFSv4 and POSIX
44	 * draft ACLs.  In POSIX, there may be only one entry for the particular
45	 * user or group.  In NFSv4 ACL, there may be any number of them.  We're
46	 * trying to be more specific here in that case.
47	 */
48	switch (_entry_brand(a)) {
49	case ACL_BRAND_NFS4:
50		if (a->ae_tag != b->ae_tag || a->ae_entry_type != b->ae_entry_type)
51			return (0);
52
53		/* If ae_ids matter, compare them as well. */
54		if (a->ae_tag == ACL_USER || a->ae_tag == ACL_GROUP) {
55			if (a->ae_id != b->ae_id)
56				return (0);
57		}
58
59		return (1);
60
61	default:
62		if ((a->ae_tag == b->ae_tag) && (a->ae_id == b->ae_id))
63			return (1);
64	}
65
66	return (0);
67}
68
69/*
70 * acl_delete_entry() (23.4.9): remove the ACL entry indicated by entry_d
71 * from acl.
72 */
73int
74acl_delete_entry(acl_t acl, acl_entry_t entry_d)
75{
76	struct acl_entry entry_int;
77	int i, j, found = 0;
78
79	if (acl == NULL || entry_d == NULL) {
80		errno = EINVAL;
81		return (-1);
82	}
83
84	if (_entry_brand(entry_d) != _acl_brand(acl)) {
85		errno = EINVAL;
86		return (-1);
87	}
88
89	if ((acl->ats_acl.acl_cnt < 1) ||
90	    (acl->ats_acl.acl_cnt > ACL_MAX_ENTRIES)) {
91		errno = EINVAL;
92		return (-1);
93	}
94
95	/* Use a local copy to prevent deletion of more than this entry */
96	entry_int = *entry_d;
97
98	for (i = 0; i < acl->ats_acl.acl_cnt;) {
99		if (_entry_matches(&(acl->ats_acl.acl_entry[i]), &entry_int)) {
100			/* ...shift the remaining entries... */
101			for (j = i; j < acl->ats_acl.acl_cnt - 1; ++j)
102				acl->ats_acl.acl_entry[j] =
103				    acl->ats_acl.acl_entry[j+1];
104			/* ...drop the count and zero the unused entry... */
105			acl->ats_acl.acl_cnt--;
106			bzero(&acl->ats_acl.acl_entry[j],
107			    sizeof(struct acl_entry));
108			acl->ats_cur_entry = 0;
109
110			/* Continue with the loop to remove all matching entries. */
111			found = 1;
112		} else
113			i++;
114	}
115
116	if (found)
117		return (0);
118
119	errno = EINVAL;
120	return (-1);
121}
122
123int
124acl_delete_entry_np(acl_t acl, int offset)
125{
126	struct acl *acl_int;
127	int i;
128
129	if (acl == NULL) {
130		errno = EINVAL;
131		return (-1);
132	}
133
134	acl_int = &acl->ats_acl;
135
136	if (offset < 0 || offset >= acl_int->acl_cnt) {
137		errno = EINVAL;
138		return (-1);
139	}
140
141	if ((acl->ats_acl.acl_cnt < 1) ||
142	    (acl->ats_acl.acl_cnt > ACL_MAX_ENTRIES)) {
143		errno = EINVAL;
144		return (-1);
145	}
146
147	/* ...shift the remaining entries... */
148	for (i = offset; i < acl->ats_acl.acl_cnt - 1; ++i)
149		acl->ats_acl.acl_entry[i] =
150		    acl->ats_acl.acl_entry[i+1];
151	/* ...drop the count and zero the unused entry... */
152	acl->ats_acl.acl_cnt--;
153	bzero(&acl->ats_acl.acl_entry[i],
154	    sizeof(struct acl_entry));
155	acl->ats_cur_entry = 0;
156
157	return (0);
158}
159