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#include <ipc/ipc_space.h>
55#include <ipc/ipc_port.h>
56#include <ipc/ipc_labelh.h>
57#include <kern/ipc_kobject.h>
58#include <mach/security.h>
59#include <security/mac_mach_internal.h>
60
61#if CONFIG_MACF_MACH
62zone_t ipc_labelh_zone;
63
64/*
65 * Create a new label handle in the task described by the specified space.
66 * The specified label is used in the label handle.  The associated port
67 * name is copied out to namep and the task is granted send and receive rights.
68 */
69kern_return_t
70labelh_new_user(ipc_space_t space, struct label *inl, mach_port_name_t *namep)
71{
72	kern_return_t kr;
73	ipc_labelh_t lh;
74	ipc_entry_t entry;
75	ipc_port_t port;
76
77	if (space == IS_NULL || space->is_task == NULL)
78		return (KERN_INVALID_TASK);
79
80	/* XXX - perform entrypoint check here? */
81
82	/* JMM - redo as port allocation, kobject set, and then copyout */
83	assert(!CONFIG_MACF_MACH);
84
85	/*
86	 * Note: the calling task will have a receive right for the port.
87	 * This is different from label handles that reference tasks
88	 * where the kernel holds the receive right and the caller only
89	 * gets a send right.
90	 */
91	kr = ipc_port_alloc(space, namep, &port);
92	if (kr != KERN_SUCCESS)
93		return (kr);
94	ip_reference(port);	/* ipc_port_alloc() does not add a reference */
95
96	/* Convert right to MACH_PORT_TYPE_SEND_RECEIVE */
97	port->ip_mscount++;
98	port->ip_srights++;
99	is_write_lock(space);
100	/* XXX - must validate space is still active and unwind if not */
101	entry = ipc_entry_lookup(space, *namep);
102	if (entry != IE_NULL)
103		entry->ie_bits |= MACH_PORT_TYPE_SEND;
104	is_write_unlock(space);
105
106	/* Allocate new label handle, insert port and label. */
107	lh = (ipc_labelh_t)zalloc(ipc_labelh_zone);
108	lh_lock_init(lh);
109	lh->lh_port = port;
110	lh->lh_label = *inl;
111	lh->lh_type = LABELH_TYPE_USER;
112	lh->lh_references = 1;		/* unused for LABELH_TYPE_USER */
113
114	/* Must call ipc_kobject_set() with port unlocked. */
115	ip_unlock(lh->lh_port);
116	ipc_kobject_set(lh->lh_port, (ipc_kobject_t)lh, IKOT_LABELH);
117
118	return (KERN_SUCCESS);
119}
120
121kern_return_t
122mac_label_new(ipc_space_t space, mach_port_name_t *namep, labelstr_t labelstr)
123{
124	struct label inl;
125	kern_return_t kr;
126
127	mac_task_label_init(&inl);
128	if (mac_task_label_internalize(&inl, labelstr))
129		return (KERN_INVALID_ARGUMENT);
130
131	kr = labelh_new_user(space, &inl, namep);
132	if (kr != KERN_SUCCESS) {
133		mac_task_label_destroy(&inl);
134		return (kr);
135	}
136
137	return (KERN_SUCCESS);
138}
139
140/*
141 * This function should be used to allocate label handles
142 * that are stored in other kernel objects, such as tasks.
143 * They must be released along with that object.
144 * The caller gets one reference, which can be applied to either the
145 * port or the ipc_label_t structure itself.
146 */
147ipc_labelh_t
148labelh_new(int canblock)
149{
150	ipc_labelh_t lh;
151
152	lh = (ipc_labelh_t)zalloc_canblock(ipc_labelh_zone, canblock);
153	lh_lock_init(lh);
154	lh->lh_port = ipc_port_alloc_kernel();
155	lh->lh_type = LABELH_TYPE_KERN;
156	lh->lh_references = 1;
157	ipc_kobject_set(lh->lh_port, (ipc_kobject_t)lh, IKOT_LABELH);
158
159	return (lh);
160}
161
162/*
163 * Call with old label handle locked.
164 * Returned label handle is unlocked.
165 */
166ipc_labelh_t
167labelh_duplicate(ipc_labelh_t old)
168{
169	ipc_labelh_t lh;
170
171	lh = labelh_new(0);
172	ip_lock(lh->lh_port);
173	mac_task_label_init(&lh->lh_label);
174	mac_task_label_copy(&old->lh_label, &lh->lh_label);
175	ip_unlock(lh->lh_port);
176	return (lh);
177}
178
179/*
180 * Call with old label handle locked.
181 * Returned label handle is locked.
182 */
183ipc_labelh_t
184labelh_modify(ipc_labelh_t old)
185{
186	ipc_labelh_t lh;
187
188	/*
189	 * A label handle may only have a single reference.
190	 * If there are no other references this is a no-op.
191	 * Otherwise, make a copy we can write to and return it.
192	 */
193	if (old->lh_references == 1)
194		return (old);
195	lh = labelh_duplicate(old);
196	lh_release(old);
197	lh_check_unlock(old);
198	lh_lock(lh);
199	return (lh);
200}
201
202/*
203 * Add or drop a reference on an (unlocked) label handle.
204 */
205ipc_labelh_t
206labelh_reference(ipc_labelh_t lh)
207{
208	lh_lock(lh);
209	lh_reference(lh);
210	lh_unlock(lh);
211	return (lh);
212}
213
214/*
215 * Release a reference on an (unlocked) label handle.
216 */
217void
218labelh_release(ipc_labelh_t lh)
219{
220	lh_lock(lh);
221	lh_release(lh);
222	lh_check_unlock(lh);
223}
224
225/*
226 * Deallocate space associated with the label handle backed by the
227 * specified port.  For kernel-allocated label handles the
228 * label handle reference count should be 0.  For user-allocated
229 * handles the ref count is not used (it was initialized to 1).
230 */
231void
232labelh_destroy(ipc_port_t port)
233{
234	ipc_labelh_t lh = (ipc_labelh_t) port->ip_kobject;
235
236	mac_task_label_destroy(&lh->lh_label);
237	lh_lock_destroy(lh);
238	zfree(ipc_labelh_zone, (vm_offset_t)lh);
239}
240#else
241kern_return_t
242mac_label_new(__unused ipc_space_t space,
243	      __unused mach_port_name_t *namep,
244	      __unused labelstr_t labelstr)
245{
246	return KERN_FAILURE;
247}
248#endif /* MAC_MACH */
249