1/*
2 * Copyright (c) 2001-2002 Chris D. Faulhaber
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD$");
29
30#include <sys/types.h>
31#include "namespace.h"
32#include <sys/acl.h>
33#include "un-namespace.h"
34#include <errno.h>
35#include <string.h>
36#include <stdio.h>
37
38#include "acl_support.h"
39
40static int
41_entry_matches(const acl_entry_t a, const acl_entry_t b)
42{
43	/*
44	 * There is a semantical difference here between NFSv4 and POSIX
45	 * draft ACLs.  In POSIX, there may be only one entry for the particular
46	 * user or group.  In NFSv4 ACL, there may be any number of them.  We're
47	 * trying to be more specific here in that case.
48	 */
49	switch (_entry_brand(a)) {
50	case ACL_BRAND_NFS4:
51		if (a->ae_tag != b->ae_tag || a->ae_entry_type != b->ae_entry_type)
52			return (0);
53
54		/* If ae_ids matter, compare them as well. */
55		if (a->ae_tag == ACL_USER || a->ae_tag == ACL_GROUP) {
56			if (a->ae_id != b->ae_id)
57				return (0);
58		}
59
60		return (1);
61
62	default:
63		if ((a->ae_tag == b->ae_tag) && (a->ae_id == b->ae_id))
64			return (1);
65	}
66
67	return (0);
68}
69
70/*
71 * acl_delete_entry() (23.4.9): remove the ACL entry indicated by entry_d
72 * from acl.
73 */
74int
75acl_delete_entry(acl_t acl, acl_entry_t entry_d)
76{
77	struct acl *acl_int;
78	struct acl_entry entry_int;
79	int i, j, found = 0;
80
81	if (acl == NULL || entry_d == NULL) {
82		errno = EINVAL;
83		return (-1);
84	}
85
86	acl_int = &acl->ats_acl;
87
88	if (_entry_brand(entry_d) != _acl_brand(acl)) {
89		errno = EINVAL;
90		return (-1);
91	}
92
93	if ((acl->ats_acl.acl_cnt < 1) ||
94	    (acl->ats_acl.acl_cnt > ACL_MAX_ENTRIES)) {
95		errno = EINVAL;
96		return (-1);
97	}
98
99	/* Use a local copy to prevent deletion of more than this entry */
100	entry_int = *entry_d;
101
102	for (i = 0; i < acl->ats_acl.acl_cnt;) {
103		if (_entry_matches(&(acl->ats_acl.acl_entry[i]), &entry_int)) {
104			/* ...shift the remaining entries... */
105			for (j = i; j < acl->ats_acl.acl_cnt - 1; ++j)
106				acl->ats_acl.acl_entry[j] =
107				    acl->ats_acl.acl_entry[j+1];
108			/* ...drop the count and zero the unused entry... */
109			acl->ats_acl.acl_cnt--;
110			bzero(&acl->ats_acl.acl_entry[j],
111			    sizeof(struct acl_entry));
112			acl->ats_cur_entry = 0;
113
114			/* Continue with the loop to remove all maching entries. */
115			found = 1;
116		} else
117			i++;
118	}
119
120	if (found)
121		return (0);
122
123	errno = EINVAL;
124	return (-1);
125}
126
127int
128acl_delete_entry_np(acl_t acl, int offset)
129{
130	struct acl *acl_int;
131	int i;
132
133	if (acl == NULL) {
134		errno = EINVAL;
135		return (-1);
136	}
137
138	acl_int = &acl->ats_acl;
139
140	if (offset < 0 || offset >= acl_int->acl_cnt) {
141		errno = EINVAL;
142		return (-1);
143	}
144
145	if ((acl->ats_acl.acl_cnt < 1) ||
146	    (acl->ats_acl.acl_cnt > ACL_MAX_ENTRIES)) {
147		errno = EINVAL;
148		return (-1);
149	}
150
151	/* ...shift the remaining entries... */
152	for (i = offset; i < acl->ats_acl.acl_cnt - 1; ++i)
153		acl->ats_acl.acl_entry[i] =
154		    acl->ats_acl.acl_entry[i+1];
155	/* ...drop the count and zero the unused entry... */
156	acl->ats_acl.acl_cnt--;
157	bzero(&acl->ats_acl.acl_entry[i],
158	    sizeof(struct acl_entry));
159	acl->ats_cur_entry = 0;
160
161	return (0);
162}
163