1/*
2 * Copyright (c) 2007 Apple Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28/*-
29 * Copyright (c) 2005-2006 SPARTA, Inc.
30 * All rights reserved.
31 *
32 * Redistribution and use in source and binary forms, with or without
33 * modification, are permitted provided that the following conditions
34 * are met:
35 * 1. Redistributions of source code must retain the above copyright
36 *    notice, this list of conditions and the following disclaimer.
37 * 2. Redistributions in binary form must reproduce the above copyright
38 *    notice, this list of conditions and the following disclaimer in the
39 *    documentation and/or other materials provided with the distribution.
40 *
41 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51 * SUCH DAMAGE.
52 */
53
54#ifndef _IPC_LABELH_H_
55#define _IPC_LABELH_H_
56
57#include <kern/lock.h>
58#include <ipc/ipc_port.h>
59#include <security/_label.h>
60
61#if CONFIG_MACF_MACH
62typedef struct ipc_labelh
63{
64	natural_t         lh_references;
65	int               lh_type;
66	struct label      lh_label;
67	ipc_port_t        lh_port;
68	decl_lck_mtx_data(,	lh_lock_data)
69} *ipc_labelh_t;
70
71#define	LABELH_TYPE_KERN	0
72#define	LABELH_TYPE_USER	1
73
74void labelh_destroy(ipc_port_t port);
75ipc_labelh_t labelh_duplicate(ipc_labelh_t old);
76ipc_labelh_t labelh_modify(ipc_labelh_t old);
77ipc_labelh_t labelh_new(int canblock);
78kern_return_t labelh_new_user(ipc_space_t, struct label *, mach_port_name_t *);
79void labelh_release(ipc_labelh_t lh);
80ipc_labelh_t labelh_reference(ipc_labelh_t lh);
81
82#define lh_reference(lh)	((lh)->lh_references++)
83#define lh_release(lh)						\
84MACRO_BEGIN							\
85	assert((lh)->lh_references > 0);			\
86	(lh)->lh_references--;					\
87MACRO_END
88
89extern zone_t ipc_labelh_zone;
90
91#define lh_lock_init(lh)	lck_mtx_init(&(lh)->lh_lock_data, &ipc_lck_grp, &ipc_lck_attr)
92#define lh_lock_destroy(lh)	lck_mtx_destroy(&(lh)->lh_lock_data, &ipc_lck_grp)
93#define lh_lock(lh)			lck_mtx_lock(&(lh)->lh_lock_data)
94#define lh_unlock(lh)		lck_mtx_unlock(&(lh)->lh_lock_data)
95
96/*
97 * Check the number of references the label handle has left.
98 * If there are 0 references and this is a kernel-allocated
99 * label handle, deallocate the associated port.  The
100 * storage space for the label handle will be deallocated
101 * as part of the port destruction.  User-allocated label
102 * handles are destroyed along with their ports.
103 */
104#define lh_check_unlock(lh)					\
105MACRO_BEGIN							\
106	_VOLATILE_ natural_t _refs = (lh)->lh_references;	\
107								\
108	lh_unlock(lh);						\
109	if (_refs == 0 && (lh)->lh_type == LABELH_TYPE_KERN)	\
110		ipc_port_dealloc_kernel((lh)->lh_port);		\
111MACRO_END
112
113#endif /* MAC_MACH */
114#endif /* _IPC_LABELH_H_ */
115