xref: /illumos-gate/usr/src/common/acl/acl_common.c (revision f48205be)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #pragma ident	"%Z%%M%	%I%	%E% SMI"
27 
28 #include <sys/types.h>
29 #include <sys/acl.h>
30 #include <sys/stat.h>
31 #if defined(_KERNEL)
32 #include <sys/systm.h>
33 #else
34 #include <errno.h>
35 #include <stdlib.h>
36 #include <strings.h>
37 #include <assert.h>
38 #define	ASSERT	assert
39 #endif
40 
41 
42 ace_t trivial_acl[] = {
43 	{(uid_t)-1, 0, ACE_OWNER, ACE_ACCESS_DENIED_ACE_TYPE},
44 	{(uid_t)-1, ACE_WRITE_ACL|ACE_WRITE_OWNER|ACE_WRITE_ATTRIBUTES|
45 	    ACE_WRITE_NAMED_ATTRS, ACE_OWNER, ACE_ACCESS_ALLOWED_ACE_TYPE},
46 	{(uid_t)-1, 0, ACE_GROUP|ACE_IDENTIFIER_GROUP,
47 	    ACE_ACCESS_DENIED_ACE_TYPE},
48 	{(uid_t)-1, 0, ACE_GROUP|ACE_IDENTIFIER_GROUP,
49 	    ACE_ACCESS_ALLOWED_ACE_TYPE},
50 	{(uid_t)-1, ACE_WRITE_ACL|ACE_WRITE_OWNER| ACE_WRITE_ATTRIBUTES|
51 	    ACE_WRITE_NAMED_ATTRS, ACE_EVERYONE, ACE_ACCESS_DENIED_ACE_TYPE},
52 	{(uid_t)-1, ACE_READ_ACL|ACE_READ_ATTRIBUTES|ACE_READ_NAMED_ATTRS|
53 	    ACE_SYNCHRONIZE, ACE_EVERYONE, ACE_ACCESS_ALLOWED_ACE_TYPE}
54 };
55 
56 
57 void
58 adjust_ace_pair(ace_t *pair, mode_t mode)
59 {
60 	if (mode & S_IROTH)
61 		pair[1].a_access_mask |= ACE_READ_DATA;
62 	else
63 		pair[0].a_access_mask |= ACE_READ_DATA;
64 	if (mode & S_IWOTH)
65 		pair[1].a_access_mask |=
66 		    ACE_WRITE_DATA|ACE_APPEND_DATA;
67 	else
68 		pair[0].a_access_mask |=
69 		    ACE_WRITE_DATA|ACE_APPEND_DATA;
70 	if (mode & S_IXOTH)
71 		pair[1].a_access_mask |= ACE_EXECUTE;
72 	else
73 		pair[0].a_access_mask |= ACE_EXECUTE;
74 }
75 
76 /*
77  * ace_trivial:
78  * determine whether an ace_t acl is trivial
79  *
80  * Trivialness implys that the acl is composed of only
81  * owner, group, everyone entries.  ACL can't
82  * have read_acl denied, and write_owner/write_acl/write_attributes
83  * can only be owner@ entry.
84  */
85 int
86 ace_trivial(ace_t *acep, int aclcnt)
87 {
88 	int i;
89 	int owner_seen = 0;
90 	int group_seen = 0;
91 	int everyone_seen = 0;
92 
93 	for (i = 0; i != aclcnt; i++) {
94 		switch (acep[i].a_flags & 0xf040) {
95 		case ACE_OWNER:
96 			if (group_seen || everyone_seen)
97 				return (1);
98 			owner_seen++;
99 			break;
100 		case ACE_GROUP|ACE_IDENTIFIER_GROUP:
101 			if (everyone_seen || owner_seen == 0)
102 				return (1);
103 			group_seen++;
104 			break;
105 
106 		case ACE_EVERYONE:
107 			if (owner_seen == 0 || group_seen == 0)
108 				return (1);
109 			everyone_seen++;
110 			break;
111 		default:
112 			return (1);
113 
114 		}
115 
116 		if (acep[i].a_flags & (ACE_FILE_INHERIT_ACE|
117 		    ACE_DIRECTORY_INHERIT_ACE|ACE_NO_PROPAGATE_INHERIT_ACE|
118 		    ACE_INHERIT_ONLY_ACE))
119 			return (1);
120 
121 		/*
122 		 * Special check for some special bits
123 		 *
124 		 * Don't allow anybody to deny reading basic
125 		 * attributes or a files ACL.
126 		 */
127 		if ((acep[i].a_access_mask &
128 		    (ACE_READ_ACL|ACE_READ_ATTRIBUTES)) &&
129 		    (acep[i].a_type == ACE_ACCESS_DENIED_ACE_TYPE))
130 			return (1);
131 
132 		/*
133 		 * Allow on owner@ to allow
134 		 * write_acl/write_owner/write_attributes
135 		 */
136 		if (acep[i].a_type == ACE_ACCESS_ALLOWED_ACE_TYPE &&
137 		    (!(acep[i].a_flags & ACE_OWNER) && (acep[i].a_access_mask &
138 		    (ACE_WRITE_OWNER|ACE_WRITE_ACL|ACE_WRITE_ATTRIBUTES))))
139 			return (1);
140 	}
141 
142 	if ((owner_seen == 0) || (group_seen == 0) || (everyone_seen == 0))
143 	    return (1);
144 
145 	return (0);
146 }
147 
148 
149 /*
150  * Generic shellsort, from K&R (1st ed, p 58.), somewhat modified.
151  * v = Ptr to array/vector of objs
152  * n = # objs in the array
153  * s = size of each obj (must be multiples of a word size)
154  * f = ptr to function to compare two objs
155  *	returns (-1 = less than, 0 = equal, 1 = greater than
156  */
157 void
158 ksort(caddr_t v, int n, int s, int (*f)())
159 {
160 	int g, i, j, ii;
161 	unsigned int *p1, *p2;
162 	unsigned int tmp;
163 
164 	/* No work to do */
165 	if (v == NULL || n <= 1)
166 		return;
167 
168 	/* Sanity check on arguments */
169 	ASSERT(((uintptr_t)v & 0x3) == 0 && (s & 0x3) == 0);
170 	ASSERT(s > 0);
171 	for (g = n / 2; g > 0; g /= 2) {
172 		for (i = g; i < n; i++) {
173 			for (j = i - g; j >= 0 &&
174 				(*f)(v + j * s, v + (j + g) * s) == 1;
175 					j -= g) {
176 				p1 = (void *)(v + j * s);
177 				p2 = (void *)(v + (j + g) * s);
178 				for (ii = 0; ii < s / 4; ii++) {
179 					tmp = *p1;
180 					*p1++ = *p2;
181 					*p2++ = tmp;
182 				}
183 			}
184 		}
185 	}
186 }
187 
188 /*
189  * Compare two acls, all fields.  Returns:
190  * -1 (less than)
191  *  0 (equal)
192  * +1 (greater than)
193  */
194 int
195 cmp2acls(void *a, void *b)
196 {
197 	aclent_t *x = (aclent_t *)a;
198 	aclent_t *y = (aclent_t *)b;
199 
200 	/* Compare types */
201 	if (x->a_type < y->a_type)
202 		return (-1);
203 	if (x->a_type > y->a_type)
204 		return (1);
205 	/* Equal types; compare id's */
206 	if (x->a_id < y->a_id)
207 		return (-1);
208 	if (x->a_id > y->a_id)
209 		return (1);
210 	/* Equal ids; compare perms */
211 	if (x->a_perm < y->a_perm)
212 		return (-1);
213 	if (x->a_perm > y->a_perm)
214 		return (1);
215 	/* Totally equal */
216 	return (0);
217 }
218