xref: /freebsd/lib/libc/posix1e/acl_strip.c (revision 4d846d260e2b9a3d4d0a701462568268cbfe7a5b) 
1aa015c8eSEdward Tomasz Napierala /*-
2*4d846d26SWarner Losh  * SPDX-License-Identifier: BSD-2-Clause
3d915a14eSPedro F. Giffuni  *
4aa015c8eSEdward Tomasz Napierala  * Copyright (c) 2001 Chris D. Faulhaber
5aa015c8eSEdward Tomasz Napierala  * All rights reserved.
6aa015c8eSEdward Tomasz Napierala  *
7aa015c8eSEdward Tomasz Napierala  * Redistribution and use in source and binary forms, with or without
8aa015c8eSEdward Tomasz Napierala  * modification, are permitted provided that the following conditions
9aa015c8eSEdward Tomasz Napierala  * are met:
10aa015c8eSEdward Tomasz Napierala  * 1. Redistributions of source code must retain the above copyright
11aa015c8eSEdward Tomasz Napierala  *    notice, this list of conditions and the following disclaimer.
12aa015c8eSEdward Tomasz Napierala  * 2. Redistributions in binary form must reproduce the above copyright
13aa015c8eSEdward Tomasz Napierala  *    notice, this list of conditions and the following disclaimer in the
14aa015c8eSEdward Tomasz Napierala  *    documentation and/or other materials provided with the distribution.
15aa015c8eSEdward Tomasz Napierala  *
16aa015c8eSEdward Tomasz Napierala  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17aa015c8eSEdward Tomasz Napierala  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18aa015c8eSEdward Tomasz Napierala  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19a303eae7SJoel Dahl  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20a303eae7SJoel Dahl  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21a303eae7SJoel Dahl  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22a303eae7SJoel Dahl  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23a303eae7SJoel Dahl  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24a303eae7SJoel Dahl  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25a303eae7SJoel Dahl  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26a303eae7SJoel Dahl  * SUCH DAMAGE.
27aa015c8eSEdward Tomasz Napierala  */
28aa015c8eSEdward Tomasz Napierala 
29aa015c8eSEdward Tomasz Napierala #include <sys/cdefs.h>
30aa015c8eSEdward Tomasz Napierala __FBSDID("$FreeBSD$");
31aa015c8eSEdward Tomasz Napierala 
32aa015c8eSEdward Tomasz Napierala #include <errno.h>
33aa015c8eSEdward Tomasz Napierala #include <stdio.h>
34aa015c8eSEdward Tomasz Napierala #include <assert.h>
35aa015c8eSEdward Tomasz Napierala #include <sys/acl.h>
364089cc8aSEdward Tomasz Napierala #include <sys/stat.h>
37aa015c8eSEdward Tomasz Napierala 
38aa015c8eSEdward Tomasz Napierala #include "acl_support.h"
39aa015c8eSEdward Tomasz Napierala 
40aa015c8eSEdward Tomasz Napierala /*
41cdec3856SEdward Tomasz Napierala  * These routines from sys/kern/subr_acl_nfs4.c are used by both kernel
42aa015c8eSEdward Tomasz Napierala  * and libc.
43aa015c8eSEdward Tomasz Napierala  */
44aa015c8eSEdward Tomasz Napierala void	acl_nfs4_sync_mode_from_acl(mode_t *_mode, const struct acl *aclp);
45cdec3856SEdward Tomasz Napierala void	acl_nfs4_trivial_from_mode_libc(struct acl *aclp, int file_owner_id,
46cdec3856SEdward Tomasz Napierala 	    int canonical_six);
47aa015c8eSEdward Tomasz Napierala 
48aa015c8eSEdward Tomasz Napierala static acl_t
494089cc8aSEdward Tomasz Napierala _nfs4_acl_strip_np(const acl_t aclp, int canonical_six)
50aa015c8eSEdward Tomasz Napierala {
51aa015c8eSEdward Tomasz Napierala 	acl_t newacl;
527945d60dSEdward Tomasz Napierala 	mode_t mode = 0;
53aa015c8eSEdward Tomasz Napierala 
54aa015c8eSEdward Tomasz Napierala 	newacl = acl_init(ACL_MAX_ENTRIES);
55aa015c8eSEdward Tomasz Napierala 	if (newacl == NULL) {
56aa015c8eSEdward Tomasz Napierala 		errno = ENOMEM;
57aa015c8eSEdward Tomasz Napierala 		return (NULL);
58aa015c8eSEdward Tomasz Napierala 	}
59aa015c8eSEdward Tomasz Napierala 
60aa015c8eSEdward Tomasz Napierala 	_acl_brand_as(newacl, ACL_BRAND_NFS4);
61aa015c8eSEdward Tomasz Napierala 
62aa015c8eSEdward Tomasz Napierala 	acl_nfs4_sync_mode_from_acl(&mode, &(aclp->ats_acl));
63cdec3856SEdward Tomasz Napierala 	acl_nfs4_trivial_from_mode_libc(&(newacl->ats_acl), mode, canonical_six);
64aa015c8eSEdward Tomasz Napierala 
65aa015c8eSEdward Tomasz Napierala 	return (newacl);
66aa015c8eSEdward Tomasz Napierala }
67aa015c8eSEdward Tomasz Napierala 
68aa015c8eSEdward Tomasz Napierala static acl_t
69aa015c8eSEdward Tomasz Napierala _posix1e_acl_strip_np(const acl_t aclp, int recalculate_mask)
70aa015c8eSEdward Tomasz Napierala {
71aa015c8eSEdward Tomasz Napierala 	acl_t acl_new, acl_old;
72aa015c8eSEdward Tomasz Napierala 	acl_entry_t entry, entry_new;
73aa015c8eSEdward Tomasz Napierala 	acl_tag_t tag;
74aa015c8eSEdward Tomasz Napierala 	int entry_id, have_mask_entry;
75aa015c8eSEdward Tomasz Napierala 
76aa015c8eSEdward Tomasz Napierala 	assert(_acl_brand(aclp) == ACL_BRAND_POSIX);
77aa015c8eSEdward Tomasz Napierala 
78aa015c8eSEdward Tomasz Napierala 	acl_old = acl_dup(aclp);
79aa015c8eSEdward Tomasz Napierala 	if (acl_old == NULL)
80aa015c8eSEdward Tomasz Napierala 		return (NULL);
81aa015c8eSEdward Tomasz Napierala 
82aa015c8eSEdward Tomasz Napierala 	assert(_acl_brand(acl_old) == ACL_BRAND_POSIX);
83aa015c8eSEdward Tomasz Napierala 
84aa015c8eSEdward Tomasz Napierala 	have_mask_entry = 0;
85aa015c8eSEdward Tomasz Napierala 	acl_new = acl_init(ACL_MAX_ENTRIES);
86cf0f0b80SPedro F. Giffuni 	if (acl_new == NULL) {
87cf0f0b80SPedro F. Giffuni 		acl_free(acl_old);
88aa015c8eSEdward Tomasz Napierala 		return (NULL);
89cf0f0b80SPedro F. Giffuni 	}
90aa015c8eSEdward Tomasz Napierala 	tag = ACL_UNDEFINED_TAG;
91aa015c8eSEdward Tomasz Napierala 
92aa015c8eSEdward Tomasz Napierala 	/* only save the default user/group/other entries */
93aa015c8eSEdward Tomasz Napierala 	entry_id = ACL_FIRST_ENTRY;
94aa015c8eSEdward Tomasz Napierala 	while (acl_get_entry(acl_old, entry_id, &entry) == 1) {
95aa015c8eSEdward Tomasz Napierala 		entry_id = ACL_NEXT_ENTRY;
96aa015c8eSEdward Tomasz Napierala 
97aa015c8eSEdward Tomasz Napierala 		assert(_entry_brand(entry) == ACL_BRAND_POSIX);
98aa015c8eSEdward Tomasz Napierala 
99aa015c8eSEdward Tomasz Napierala 		if (acl_get_tag_type(entry, &tag) == -1)
100cf0f0b80SPedro F. Giffuni 			goto fail;
101aa015c8eSEdward Tomasz Napierala 
102aa015c8eSEdward Tomasz Napierala 		switch(tag) {
103aa015c8eSEdward Tomasz Napierala 		case ACL_USER_OBJ:
104aa015c8eSEdward Tomasz Napierala 		case ACL_GROUP_OBJ:
105aa015c8eSEdward Tomasz Napierala 		case ACL_OTHER:
106aa015c8eSEdward Tomasz Napierala 			if (acl_create_entry(&acl_new, &entry_new) == -1)
1078e6acc53SEdward Tomasz Napierala 				goto fail;
108aa015c8eSEdward Tomasz Napierala 			if (acl_copy_entry(entry_new, entry) == -1)
1098e6acc53SEdward Tomasz Napierala 				goto fail;
110aa015c8eSEdward Tomasz Napierala 			assert(_entry_brand(entry_new) == ACL_BRAND_POSIX);
111aa015c8eSEdward Tomasz Napierala 			break;
112aa015c8eSEdward Tomasz Napierala 		case ACL_MASK:
113aa015c8eSEdward Tomasz Napierala 			have_mask_entry = 1;
114aa015c8eSEdward Tomasz Napierala 			break;
115aa015c8eSEdward Tomasz Napierala 		default:
116aa015c8eSEdward Tomasz Napierala 			break;
117aa015c8eSEdward Tomasz Napierala 		}
118aa015c8eSEdward Tomasz Napierala 	}
119aa015c8eSEdward Tomasz Napierala 
120aa015c8eSEdward Tomasz Napierala 	assert(_acl_brand(acl_new) == ACL_BRAND_POSIX);
121aa015c8eSEdward Tomasz Napierala 
122aa015c8eSEdward Tomasz Napierala 	if (have_mask_entry && recalculate_mask) {
123aa015c8eSEdward Tomasz Napierala 		if (acl_calc_mask(&acl_new) == -1)
1248e6acc53SEdward Tomasz Napierala 			goto fail;
125aa015c8eSEdward Tomasz Napierala 	}
126aa015c8eSEdward Tomasz Napierala 
127aa015c8eSEdward Tomasz Napierala 	return (acl_new);
1288e6acc53SEdward Tomasz Napierala 
1298e6acc53SEdward Tomasz Napierala fail:
1308e6acc53SEdward Tomasz Napierala 	acl_free(acl_new);
1318e6acc53SEdward Tomasz Napierala 	acl_free(acl_old);
1328e6acc53SEdward Tomasz Napierala 
1338e6acc53SEdward Tomasz Napierala 	return (NULL);
134aa015c8eSEdward Tomasz Napierala }
135aa015c8eSEdward Tomasz Napierala 
136aa015c8eSEdward Tomasz Napierala acl_t
137aa015c8eSEdward Tomasz Napierala acl_strip_np(const acl_t aclp, int recalculate_mask)
138aa015c8eSEdward Tomasz Napierala {
139aa015c8eSEdward Tomasz Napierala 	switch (_acl_brand(aclp)) {
140aa015c8eSEdward Tomasz Napierala 	case ACL_BRAND_NFS4:
141e43af6d3SEdward Tomasz Napierala 		return (_nfs4_acl_strip_np(aclp, 0));
142aa015c8eSEdward Tomasz Napierala 
143aa015c8eSEdward Tomasz Napierala 	case ACL_BRAND_POSIX:
144aa015c8eSEdward Tomasz Napierala 		return (_posix1e_acl_strip_np(aclp, recalculate_mask));
145aa015c8eSEdward Tomasz Napierala 
146aa015c8eSEdward Tomasz Napierala 	default:
147aa015c8eSEdward Tomasz Napierala 		errno = EINVAL;
148aa015c8eSEdward Tomasz Napierala 		return (NULL);
149aa015c8eSEdward Tomasz Napierala 	}
150aa015c8eSEdward Tomasz Napierala }
151aa015c8eSEdward Tomasz Napierala 
152aa015c8eSEdward Tomasz Napierala /*
153aa015c8eSEdward Tomasz Napierala  * Return 1, if ACL is trivial, 0 otherwise.
154aa015c8eSEdward Tomasz Napierala  *
155aa015c8eSEdward Tomasz Napierala  * ACL is trivial, iff its meaning could be fully expressed using just file
156aa015c8eSEdward Tomasz Napierala  * mode.  In other words, ACL is trivial iff it doesn't have "+" to the right
157aa015c8eSEdward Tomasz Napierala  * of the mode bits in "ls -l" output ;-)
158aa015c8eSEdward Tomasz Napierala  */
159aa015c8eSEdward Tomasz Napierala int
160aa015c8eSEdward Tomasz Napierala acl_is_trivial_np(const acl_t aclp, int *trivialp)
161aa015c8eSEdward Tomasz Napierala {
162aa015c8eSEdward Tomasz Napierala 	acl_t tmpacl;
163aa015c8eSEdward Tomasz Napierala 	int differs;
164aa015c8eSEdward Tomasz Napierala 
165aa015c8eSEdward Tomasz Napierala 	if (aclp == NULL || trivialp == NULL) {
166aa015c8eSEdward Tomasz Napierala 		errno = EINVAL;
167aa015c8eSEdward Tomasz Napierala 		return (-1);
168aa015c8eSEdward Tomasz Napierala 	}
169aa015c8eSEdward Tomasz Napierala 
170aa015c8eSEdward Tomasz Napierala 	switch (_acl_brand(aclp)) {
171aa015c8eSEdward Tomasz Napierala 	case ACL_BRAND_POSIX:
172aa015c8eSEdward Tomasz Napierala 		if (aclp->ats_acl.acl_cnt == 3)
173aa015c8eSEdward Tomasz Napierala 			*trivialp = 1;
174aa015c8eSEdward Tomasz Napierala 		else
175aa015c8eSEdward Tomasz Napierala 			*trivialp = 0;
176aa015c8eSEdward Tomasz Napierala 
177aa015c8eSEdward Tomasz Napierala 		return (0);
178aa015c8eSEdward Tomasz Napierala 
179aa015c8eSEdward Tomasz Napierala 	case ACL_BRAND_NFS4:
180aa015c8eSEdward Tomasz Napierala 		/*
1817eaa29b5SEdward Tomasz Napierala 		 * If the ACL has more than canonical six entries,
1827eaa29b5SEdward Tomasz Napierala 		 * it's non trivial by definition.
1837eaa29b5SEdward Tomasz Napierala 		 */
1847eaa29b5SEdward Tomasz Napierala 		if (aclp->ats_acl.acl_cnt > 6) {
18578141351SEdward Tomasz Napierala 			*trivialp = 0;
1867eaa29b5SEdward Tomasz Napierala 			return (0);
1877eaa29b5SEdward Tomasz Napierala 		}
1887eaa29b5SEdward Tomasz Napierala 
1897eaa29b5SEdward Tomasz Napierala 		/*
1904089cc8aSEdward Tomasz Napierala 		 * Calculate trivial ACL - using acl_strip_np(3) - and compare
191aa015c8eSEdward Tomasz Napierala 		 * with the original.
192aa015c8eSEdward Tomasz Napierala 		 */
1934089cc8aSEdward Tomasz Napierala 		tmpacl = _nfs4_acl_strip_np(aclp, 0);
1944089cc8aSEdward Tomasz Napierala 		if (tmpacl == NULL)
1954089cc8aSEdward Tomasz Napierala 			return (-1);
1964089cc8aSEdward Tomasz Napierala 
1974089cc8aSEdward Tomasz Napierala 		differs = _acl_differs(aclp, tmpacl);
1984089cc8aSEdward Tomasz Napierala 		acl_free(tmpacl);
1994089cc8aSEdward Tomasz Napierala 
2004089cc8aSEdward Tomasz Napierala 		if (differs == 0) {
2014089cc8aSEdward Tomasz Napierala 			*trivialp = 1;
2024089cc8aSEdward Tomasz Napierala 			return (0);
2034089cc8aSEdward Tomasz Napierala 		}
2044089cc8aSEdward Tomasz Napierala 
2054089cc8aSEdward Tomasz Napierala 		/*
2064089cc8aSEdward Tomasz Napierala 		 * Try again with an old-style, "canonical six" trivial ACL.
2074089cc8aSEdward Tomasz Napierala 		 */
2084089cc8aSEdward Tomasz Napierala 		tmpacl = _nfs4_acl_strip_np(aclp, 1);
209aa015c8eSEdward Tomasz Napierala 		if (tmpacl == NULL)
210aa015c8eSEdward Tomasz Napierala 			return (-1);
211aa015c8eSEdward Tomasz Napierala 
212aa015c8eSEdward Tomasz Napierala 		differs = _acl_differs(aclp, tmpacl);
213aa015c8eSEdward Tomasz Napierala 		acl_free(tmpacl);
214aa015c8eSEdward Tomasz Napierala 
215aa015c8eSEdward Tomasz Napierala 		if (differs)
216aa015c8eSEdward Tomasz Napierala 			*trivialp = 0;
217aa015c8eSEdward Tomasz Napierala 		else
218aa015c8eSEdward Tomasz Napierala 			*trivialp = 1;
219aa015c8eSEdward Tomasz Napierala 
220aa015c8eSEdward Tomasz Napierala 		return (0);
221aa015c8eSEdward Tomasz Napierala 
222aa015c8eSEdward Tomasz Napierala 	default:
223aa015c8eSEdward Tomasz Napierala 		errno = EINVAL;
224aa015c8eSEdward Tomasz Napierala 		return (-1);
225aa015c8eSEdward Tomasz Napierala 	}
226aa015c8eSEdward Tomasz Napierala }
227