mac_label.c revision 166531 
1/*-
2 * Copyright (c) 2003-2004 Networks Associates Technology, Inc.
3 * All rights reserved.
4 *
5 * This software was developed for the FreeBSD Project in part by Network
6 * Associates Laboratories, the Security Research Division of Network
7 * Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"),
8 * as part of the DARPA CHATS research program.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32#include <sys/cdefs.h>
33__FBSDID("$FreeBSD: head/sys/security/mac/mac_label.c 166531 2007-02-06 10:59:23Z rwatson $");
34
35#include "opt_mac.h"
36
37#include <sys/param.h>
38#include <sys/sysctl.h>
39#include <sys/systm.h>
40
41#include <vm/uma.h>
42
43#include <security/mac/mac_framework.h>
44#include <security/mac/mac_internal.h>
45
46/*
47 * zone_label is the UMA zone from which most labels are allocated.  Label
48 * structures are initialized to zero bytes so that policies see a NULL/0
49 * slot on first use, even if the policy is loaded after the label is
50 * allocated for an object.
51 */
52static uma_zone_t	zone_label;
53
54static int	mac_labelzone_ctor(void *mem, int size, void *arg, int flags);
55static void	mac_labelzone_dtor(void *mem, int size, void *arg);
56
57void
58mac_labelzone_init(void)
59{
60
61	zone_label = uma_zcreate("MAC labels", sizeof(struct label),
62	    mac_labelzone_ctor, mac_labelzone_dtor, NULL, NULL,
63	    UMA_ALIGN_PTR, 0);
64}
65
66/*
67 * mac_init_label() and mac_destroy_label() are exported so that they can be
68 * used in mbuf tag initialization, where labels are not slab allocated from
69 * the zone_label zone.
70 */
71void
72mac_init_label(struct label *label)
73{
74
75	bzero(label, sizeof(*label));
76	label->l_flags = MAC_FLAG_INITIALIZED;
77}
78
79void
80mac_destroy_label(struct label *label)
81{
82
83	KASSERT(label->l_flags & MAC_FLAG_INITIALIZED,
84	    ("destroying uninitialized label"));
85
86#ifdef DIAGNOSTIC
87	bzero(label, sizeof(*label));
88#else
89	label->l_flags &= ~MAC_FLAG_INITIALIZED;
90#endif
91}
92
93
94static int
95mac_labelzone_ctor(void *mem, int size, void *arg, int flags)
96{
97	struct label *label;
98
99	KASSERT(size == sizeof(*label), ("mac_labelzone_ctor: wrong size\n"));
100	label = mem;
101	mac_init_label(label);
102	return (0);
103}
104
105static void
106mac_labelzone_dtor(void *mem, int size, void *arg)
107{
108	struct label *label;
109
110	KASSERT(size == sizeof(*label), ("mac_labelzone_dtor: wrong size\n"));
111	label = mem;
112	mac_destroy_label(label);
113}
114
115struct label *
116mac_labelzone_alloc(int flags)
117{
118
119	return (uma_zalloc(zone_label, flags));
120}
121
122void
123mac_labelzone_free(struct label *label)
124{
125
126	uma_zfree(zone_label, label);
127}
128