xref: /freebsd/lib/libc/posix1e/acl_strip.c (revision 8e6acc531a584b0e2d3d1fc5ec9b481391cd0fe8)
1aa015c8eSEdward Tomasz Napierala /*-
2aa015c8eSEdward Tomasz Napierala  * Copyright (c) 2001 Chris D. Faulhaber
3aa015c8eSEdward Tomasz Napierala  * All rights reserved.
4aa015c8eSEdward Tomasz Napierala  *
5aa015c8eSEdward Tomasz Napierala  * Redistribution and use in source and binary forms, with or without
6aa015c8eSEdward Tomasz Napierala  * modification, are permitted provided that the following conditions
7aa015c8eSEdward Tomasz Napierala  * are met:
8aa015c8eSEdward Tomasz Napierala  * 1. Redistributions of source code must retain the above copyright
9aa015c8eSEdward Tomasz Napierala  *    notice, this list of conditions and the following disclaimer.
10aa015c8eSEdward Tomasz Napierala  * 2. Redistributions in binary form must reproduce the above copyright
11aa015c8eSEdward Tomasz Napierala  *    notice, this list of conditions and the following disclaimer in the
12aa015c8eSEdward Tomasz Napierala  *    documentation and/or other materials provided with the distribution.
13aa015c8eSEdward Tomasz Napierala  *
14aa015c8eSEdward Tomasz Napierala  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15aa015c8eSEdward Tomasz Napierala  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16aa015c8eSEdward Tomasz Napierala  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17a303eae7SJoel Dahl  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18a303eae7SJoel Dahl  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19a303eae7SJoel Dahl  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20a303eae7SJoel Dahl  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21a303eae7SJoel Dahl  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22a303eae7SJoel Dahl  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23a303eae7SJoel Dahl  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24a303eae7SJoel Dahl  * SUCH DAMAGE.
25aa015c8eSEdward Tomasz Napierala  */
26aa015c8eSEdward Tomasz Napierala 
27aa015c8eSEdward Tomasz Napierala #include <sys/cdefs.h>
28aa015c8eSEdward Tomasz Napierala __FBSDID("$FreeBSD$");
29aa015c8eSEdward Tomasz Napierala 
30aa015c8eSEdward Tomasz Napierala #include <errno.h>
31aa015c8eSEdward Tomasz Napierala #include <stdio.h>
32aa015c8eSEdward Tomasz Napierala #include <assert.h>
33aa015c8eSEdward Tomasz Napierala #include <sys/acl.h>
344089cc8aSEdward Tomasz Napierala #include <sys/stat.h>
35aa015c8eSEdward Tomasz Napierala 
36aa015c8eSEdward Tomasz Napierala #include "acl_support.h"
37aa015c8eSEdward Tomasz Napierala 
38aa015c8eSEdward Tomasz Napierala /*
39cdec3856SEdward Tomasz Napierala  * These routines from sys/kern/subr_acl_nfs4.c are used by both kernel
40aa015c8eSEdward Tomasz Napierala  * and libc.
41aa015c8eSEdward Tomasz Napierala  */
42aa015c8eSEdward Tomasz Napierala void	acl_nfs4_sync_mode_from_acl(mode_t *_mode, const struct acl *aclp);
43cdec3856SEdward Tomasz Napierala void	acl_nfs4_trivial_from_mode_libc(struct acl *aclp, int file_owner_id,
44cdec3856SEdward Tomasz Napierala 	    int canonical_six);
45aa015c8eSEdward Tomasz Napierala 
46aa015c8eSEdward Tomasz Napierala static acl_t
474089cc8aSEdward Tomasz Napierala _nfs4_acl_strip_np(const acl_t aclp, int canonical_six)
48aa015c8eSEdward Tomasz Napierala {
49aa015c8eSEdward Tomasz Napierala 	acl_t newacl;
507945d60dSEdward Tomasz Napierala 	mode_t mode = 0;
51aa015c8eSEdward Tomasz Napierala 
52aa015c8eSEdward Tomasz Napierala 	newacl = acl_init(ACL_MAX_ENTRIES);
53aa015c8eSEdward Tomasz Napierala 	if (newacl == NULL) {
54aa015c8eSEdward Tomasz Napierala 		errno = ENOMEM;
55aa015c8eSEdward Tomasz Napierala 		return (NULL);
56aa015c8eSEdward Tomasz Napierala 	}
57aa015c8eSEdward Tomasz Napierala 
58aa015c8eSEdward Tomasz Napierala 	_acl_brand_as(newacl, ACL_BRAND_NFS4);
59aa015c8eSEdward Tomasz Napierala 
60aa015c8eSEdward Tomasz Napierala 	acl_nfs4_sync_mode_from_acl(&mode, &(aclp->ats_acl));
61cdec3856SEdward Tomasz Napierala 	acl_nfs4_trivial_from_mode_libc(&(newacl->ats_acl), mode, canonical_six);
62aa015c8eSEdward Tomasz Napierala 
63aa015c8eSEdward Tomasz Napierala 	return (newacl);
64aa015c8eSEdward Tomasz Napierala }
65aa015c8eSEdward Tomasz Napierala 
66aa015c8eSEdward Tomasz Napierala static acl_t
67aa015c8eSEdward Tomasz Napierala _posix1e_acl_strip_np(const acl_t aclp, int recalculate_mask)
68aa015c8eSEdward Tomasz Napierala {
69aa015c8eSEdward Tomasz Napierala 	acl_t acl_new, acl_old;
70aa015c8eSEdward Tomasz Napierala 	acl_entry_t entry, entry_new;
71aa015c8eSEdward Tomasz Napierala 	acl_permset_t perm;
72aa015c8eSEdward Tomasz Napierala 	acl_tag_t tag;
73aa015c8eSEdward Tomasz Napierala 	int entry_id, have_mask_entry;
74aa015c8eSEdward Tomasz Napierala 
75aa015c8eSEdward Tomasz Napierala 	assert(_acl_brand(aclp) == ACL_BRAND_POSIX);
76aa015c8eSEdward Tomasz Napierala 
77aa015c8eSEdward Tomasz Napierala 	acl_old = acl_dup(aclp);
78aa015c8eSEdward Tomasz Napierala 	if (acl_old == NULL)
79aa015c8eSEdward Tomasz Napierala 		return (NULL);
80aa015c8eSEdward Tomasz Napierala 
81aa015c8eSEdward Tomasz Napierala 	assert(_acl_brand(acl_old) == ACL_BRAND_POSIX);
82aa015c8eSEdward Tomasz Napierala 
83aa015c8eSEdward Tomasz Napierala 	have_mask_entry = 0;
84aa015c8eSEdward Tomasz Napierala 	acl_new = acl_init(ACL_MAX_ENTRIES);
85cf0f0b80SPedro F. Giffuni 	if (acl_new == NULL) {
86cf0f0b80SPedro F. Giffuni 		acl_free(acl_old);
87aa015c8eSEdward Tomasz Napierala 		return (NULL);
88cf0f0b80SPedro F. Giffuni 	}
89aa015c8eSEdward Tomasz Napierala 	tag = ACL_UNDEFINED_TAG;
90aa015c8eSEdward Tomasz Napierala 
91aa015c8eSEdward Tomasz Napierala 	/* only save the default user/group/other entries */
92aa015c8eSEdward Tomasz Napierala 	entry_id = ACL_FIRST_ENTRY;
93aa015c8eSEdward Tomasz Napierala 	while (acl_get_entry(acl_old, entry_id, &entry) == 1) {
94aa015c8eSEdward Tomasz Napierala 		entry_id = ACL_NEXT_ENTRY;
95aa015c8eSEdward Tomasz Napierala 
96aa015c8eSEdward Tomasz Napierala 		assert(_entry_brand(entry) == ACL_BRAND_POSIX);
97aa015c8eSEdward Tomasz Napierala 
98aa015c8eSEdward Tomasz Napierala 		if (acl_get_tag_type(entry, &tag) == -1)
99cf0f0b80SPedro F. Giffuni 			goto fail;
100aa015c8eSEdward Tomasz Napierala 
101aa015c8eSEdward Tomasz Napierala 		switch(tag) {
102aa015c8eSEdward Tomasz Napierala 		case ACL_USER_OBJ:
103aa015c8eSEdward Tomasz Napierala 		case ACL_GROUP_OBJ:
104aa015c8eSEdward Tomasz Napierala 		case ACL_OTHER:
105aa015c8eSEdward Tomasz Napierala 			if (acl_get_tag_type(entry, &tag) == -1)
106cf0f0b80SPedro F. Giffuni 				goto fail;
107aa015c8eSEdward Tomasz Napierala 			if (acl_get_permset(entry, &perm) == -1)
108cf0f0b80SPedro F. Giffuni 				goto fail;
109aa015c8eSEdward Tomasz Napierala 			if (acl_create_entry(&acl_new, &entry_new) == -1)
110*8e6acc53SEdward Tomasz Napierala 				goto fail;
111aa015c8eSEdward Tomasz Napierala 			if (acl_set_tag_type(entry_new, tag) == -1)
112*8e6acc53SEdward Tomasz Napierala 				goto fail;
113aa015c8eSEdward Tomasz Napierala 			if (acl_set_permset(entry_new, perm) == -1)
114*8e6acc53SEdward Tomasz Napierala 				goto fail;
115aa015c8eSEdward Tomasz Napierala 			if (acl_copy_entry(entry_new, entry) == -1)
116*8e6acc53SEdward Tomasz Napierala 				goto fail;
117aa015c8eSEdward Tomasz Napierala 			assert(_entry_brand(entry_new) == ACL_BRAND_POSIX);
118aa015c8eSEdward Tomasz Napierala 			break;
119aa015c8eSEdward Tomasz Napierala 		case ACL_MASK:
120aa015c8eSEdward Tomasz Napierala 			have_mask_entry = 1;
121aa015c8eSEdward Tomasz Napierala 			break;
122aa015c8eSEdward Tomasz Napierala 		default:
123aa015c8eSEdward Tomasz Napierala 			break;
124aa015c8eSEdward Tomasz Napierala 		}
125aa015c8eSEdward Tomasz Napierala 	}
126aa015c8eSEdward Tomasz Napierala 
127aa015c8eSEdward Tomasz Napierala 	assert(_acl_brand(acl_new) == ACL_BRAND_POSIX);
128aa015c8eSEdward Tomasz Napierala 
129aa015c8eSEdward Tomasz Napierala 	if (have_mask_entry && recalculate_mask) {
130aa015c8eSEdward Tomasz Napierala 		if (acl_calc_mask(&acl_new) == -1)
131*8e6acc53SEdward Tomasz Napierala 			goto fail;
132aa015c8eSEdward Tomasz Napierala 	}
133aa015c8eSEdward Tomasz Napierala 
134aa015c8eSEdward Tomasz Napierala 	return (acl_new);
135*8e6acc53SEdward Tomasz Napierala 
136*8e6acc53SEdward Tomasz Napierala fail:
137*8e6acc53SEdward Tomasz Napierala 	acl_free(acl_new);
138*8e6acc53SEdward Tomasz Napierala 	acl_free(acl_old);
139*8e6acc53SEdward Tomasz Napierala 
140*8e6acc53SEdward Tomasz Napierala 	return (NULL);
141aa015c8eSEdward Tomasz Napierala }
142aa015c8eSEdward Tomasz Napierala 
143aa015c8eSEdward Tomasz Napierala acl_t
144aa015c8eSEdward Tomasz Napierala acl_strip_np(const acl_t aclp, int recalculate_mask)
145aa015c8eSEdward Tomasz Napierala {
146aa015c8eSEdward Tomasz Napierala 	switch (_acl_brand(aclp)) {
147aa015c8eSEdward Tomasz Napierala 	case ACL_BRAND_NFS4:
148e43af6d3SEdward Tomasz Napierala 		return (_nfs4_acl_strip_np(aclp, 0));
149aa015c8eSEdward Tomasz Napierala 
150aa015c8eSEdward Tomasz Napierala 	case ACL_BRAND_POSIX:
151aa015c8eSEdward Tomasz Napierala 		return (_posix1e_acl_strip_np(aclp, recalculate_mask));
152aa015c8eSEdward Tomasz Napierala 
153aa015c8eSEdward Tomasz Napierala 	default:
154aa015c8eSEdward Tomasz Napierala 		errno = EINVAL;
155aa015c8eSEdward Tomasz Napierala 		return (NULL);
156aa015c8eSEdward Tomasz Napierala 	}
157aa015c8eSEdward Tomasz Napierala }
158aa015c8eSEdward Tomasz Napierala 
159aa015c8eSEdward Tomasz Napierala /*
160aa015c8eSEdward Tomasz Napierala  * Return 1, if ACL is trivial, 0 otherwise.
161aa015c8eSEdward Tomasz Napierala  *
162aa015c8eSEdward Tomasz Napierala  * ACL is trivial, iff its meaning could be fully expressed using just file
163aa015c8eSEdward Tomasz Napierala  * mode.  In other words, ACL is trivial iff it doesn't have "+" to the right
164aa015c8eSEdward Tomasz Napierala  * of the mode bits in "ls -l" output ;-)
165aa015c8eSEdward Tomasz Napierala  */
166aa015c8eSEdward Tomasz Napierala int
167aa015c8eSEdward Tomasz Napierala acl_is_trivial_np(const acl_t aclp, int *trivialp)
168aa015c8eSEdward Tomasz Napierala {
169aa015c8eSEdward Tomasz Napierala 	acl_t tmpacl;
170aa015c8eSEdward Tomasz Napierala 	int differs;
171aa015c8eSEdward Tomasz Napierala 
172aa015c8eSEdward Tomasz Napierala 	if (aclp == NULL || trivialp == NULL) {
173aa015c8eSEdward Tomasz Napierala 		errno = EINVAL;
174aa015c8eSEdward Tomasz Napierala 		return (-1);
175aa015c8eSEdward Tomasz Napierala 	}
176aa015c8eSEdward Tomasz Napierala 
177aa015c8eSEdward Tomasz Napierala 	switch (_acl_brand(aclp)) {
178aa015c8eSEdward Tomasz Napierala 	case ACL_BRAND_POSIX:
179aa015c8eSEdward Tomasz Napierala 		if (aclp->ats_acl.acl_cnt == 3)
180aa015c8eSEdward Tomasz Napierala 			*trivialp = 1;
181aa015c8eSEdward Tomasz Napierala 		else
182aa015c8eSEdward Tomasz Napierala 			*trivialp = 0;
183aa015c8eSEdward Tomasz Napierala 
184aa015c8eSEdward Tomasz Napierala 		return (0);
185aa015c8eSEdward Tomasz Napierala 
186aa015c8eSEdward Tomasz Napierala 	case ACL_BRAND_NFS4:
187aa015c8eSEdward Tomasz Napierala 		/*
1887eaa29b5SEdward Tomasz Napierala 		 * If the ACL has more than canonical six entries,
1897eaa29b5SEdward Tomasz Napierala 		 * it's non trivial by definition.
1907eaa29b5SEdward Tomasz Napierala 		 */
1917eaa29b5SEdward Tomasz Napierala 		if (aclp->ats_acl.acl_cnt > 6) {
19278141351SEdward Tomasz Napierala 			*trivialp = 0;
1937eaa29b5SEdward Tomasz Napierala 			return (0);
1947eaa29b5SEdward Tomasz Napierala 		}
1957eaa29b5SEdward Tomasz Napierala 
1967eaa29b5SEdward Tomasz Napierala 		/*
1974089cc8aSEdward Tomasz Napierala 		 * Calculate trivial ACL - using acl_strip_np(3) - and compare
198aa015c8eSEdward Tomasz Napierala 		 * with the original.
199aa015c8eSEdward Tomasz Napierala 		 */
2004089cc8aSEdward Tomasz Napierala 		tmpacl = _nfs4_acl_strip_np(aclp, 0);
2014089cc8aSEdward Tomasz Napierala 		if (tmpacl == NULL)
2024089cc8aSEdward Tomasz Napierala 			return (-1);
2034089cc8aSEdward Tomasz Napierala 
2044089cc8aSEdward Tomasz Napierala 		differs = _acl_differs(aclp, tmpacl);
2054089cc8aSEdward Tomasz Napierala 		acl_free(tmpacl);
2064089cc8aSEdward Tomasz Napierala 
2074089cc8aSEdward Tomasz Napierala 		if (differs == 0) {
2084089cc8aSEdward Tomasz Napierala 			*trivialp = 1;
2094089cc8aSEdward Tomasz Napierala 			return (0);
2104089cc8aSEdward Tomasz Napierala 		}
2114089cc8aSEdward Tomasz Napierala 
2124089cc8aSEdward Tomasz Napierala 		/*
2134089cc8aSEdward Tomasz Napierala 		 * Try again with an old-style, "canonical six" trivial ACL.
2144089cc8aSEdward Tomasz Napierala 		 */
2154089cc8aSEdward Tomasz Napierala 		tmpacl = _nfs4_acl_strip_np(aclp, 1);
216aa015c8eSEdward Tomasz Napierala 		if (tmpacl == NULL)
217aa015c8eSEdward Tomasz Napierala 			return (-1);
218aa015c8eSEdward Tomasz Napierala 
219aa015c8eSEdward Tomasz Napierala 		differs = _acl_differs(aclp, tmpacl);
220aa015c8eSEdward Tomasz Napierala 		acl_free(tmpacl);
221aa015c8eSEdward Tomasz Napierala 
222aa015c8eSEdward Tomasz Napierala 		if (differs)
223aa015c8eSEdward Tomasz Napierala 			*trivialp = 0;
224aa015c8eSEdward Tomasz Napierala 		else
225aa015c8eSEdward Tomasz Napierala 			*trivialp = 1;
226aa015c8eSEdward Tomasz Napierala 
227aa015c8eSEdward Tomasz Napierala 		return (0);
228aa015c8eSEdward Tomasz Napierala 
229aa015c8eSEdward Tomasz Napierala 	default:
230aa015c8eSEdward Tomasz Napierala 		errno = EINVAL;
231aa015c8eSEdward Tomasz Napierala 		return (-1);
232aa015c8eSEdward Tomasz Napierala 	}
233aa015c8eSEdward Tomasz Napierala }
234