1/*
2 * Copyright (c) 2006-2007 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) 1999, 2000, 2001, 2002 Robert N. M. Watson
30 * Copyright (c) 2001 Ilmar S. Habibulin
31 * Copyright (c) 2001, 2002, 2003, 2004 Networks Associates Technology, Inc.
32 *
33 * This software was developed by Robert Watson and Ilmar Habibulin for the
34 * TrustedBSD Project.
35 *
36 * This software was developed for the FreeBSD Project in part by Network
37 * Associates Laboratories, the Security Research Division of Network
38 * Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"),
39 * as part of the DARPA CHATS research program.
40 *
41 * Redistribution and use in source and binary forms, with or without
42 * modification, are permitted provided that the following conditions
43 * are met:
44 * 1. Redistributions of source code must retain the above copyright
45 *    notice, this list of conditions and the following disclaimer.
46 * 2. Redistributions in binary form must reproduce the above copyright
47 *    notice, this list of conditions and the following disclaimer in the
48 *    documentation and/or other materials provided with the distribution.
49 *
50 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
51 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
52 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
53 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
54 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
55 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
56 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
57 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
58 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
59 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
60 * SUCH DAMAGE.
61 *
62 */
63#include <sys/param.h>
64#include <sys/types.h>
65#include <sys/vnode.h>
66#include <sys/vnode_internal.h>
67#include <sys/kauth.h>
68#include <sys/queue.h>
69#include <security/mac_internal.h>
70#include <bsd/bsm/audit.h>
71#include <bsd/security/audit/audit.h>
72#include <bsd/sys/malloc.h>
73#include <vm/vm_kern.h>
74#include <kern/kalloc.h>
75#include <kern/zalloc.h>
76
77#if CONFIG_AUDIT
78
79/* The zone allocator is initialized in mac_base.c. */
80zone_t mac_audit_data_zone;
81
82int
83mac_system_check_audit(struct ucred *cred, void *record, int length)
84{
85	int error;
86
87	MAC_CHECK(system_check_audit, cred, record, length);
88
89	return (error);
90}
91
92int
93mac_system_check_auditon(struct ucred *cred, int cmd)
94{
95	int error;
96
97	MAC_CHECK(system_check_auditon, cred, cmd);
98
99	return (error);
100}
101
102int
103mac_system_check_auditctl(struct ucred *cred, struct vnode *vp)
104{
105	int error;
106	struct label *vl = vp ? vp->v_label : NULL;
107
108	MAC_CHECK(system_check_auditctl, cred, vp, vl);
109
110	return (error);
111}
112
113int
114mac_proc_check_getauid(struct proc *curp)
115{
116	kauth_cred_t cred;
117	int error;
118
119	if (!mac_proc_enforce ||
120	    !mac_proc_check_enforce(curp, MAC_PROC_ENFORCE))
121		return 0;
122
123	cred = kauth_cred_proc_ref(curp);
124	MAC_CHECK(proc_check_getauid, cred);
125	kauth_cred_unref(&cred);
126
127	return (error);
128}
129
130int
131mac_proc_check_setauid(struct proc *curp, uid_t auid)
132{
133	kauth_cred_t cred;
134	int error;
135
136	if (!mac_proc_enforce ||
137	    !mac_proc_check_enforce(curp, MAC_PROC_ENFORCE))
138		return 0;
139
140	cred = kauth_cred_proc_ref(curp);
141	MAC_CHECK(proc_check_setauid, cred, auid);
142	kauth_cred_unref(&cred);
143
144	return (error);
145}
146
147int
148mac_proc_check_getaudit(struct proc *curp)
149{
150	kauth_cred_t cred;
151	int error;
152
153	if (!mac_proc_enforce ||
154	    !mac_proc_check_enforce(curp, MAC_PROC_ENFORCE))
155		return 0;
156
157	cred = kauth_cred_proc_ref(curp);
158	MAC_CHECK(proc_check_getaudit, cred);
159	kauth_cred_unref(&cred);
160
161	return (error);
162}
163
164int
165mac_proc_check_setaudit(struct proc *curp, struct auditinfo_addr *ai)
166{
167	kauth_cred_t cred;
168	int error;
169
170	if (!mac_proc_enforce ||
171	    !mac_proc_check_enforce(curp, MAC_PROC_ENFORCE))
172		return 0;
173
174	cred = kauth_cred_proc_ref(curp);
175	MAC_CHECK(proc_check_setaudit, cred, ai);
176	kauth_cred_unref(&cred);
177
178	return (error);
179}
180
181#if 0
182/*
183 * This is the framework entry point for MAC policies to use to add
184 * arbitrary data to the current audit record.
185 * (Currently not supported, as no existing audit viewers would
186 * display this format)
187 *
188 */
189int
190mac_audit_data(int len, u_char *data, mac_policy_handle_t handle)
191{
192	char *sanitized;
193
194	if ((len <= 0) || (len > MAC_AUDIT_DATA_LIMIT))
195		return (EINVAL);
196
197	sanitized = (char *)zalloc(mac_audit_data_zone);
198
199	bcopy(data, sanitized, len);
200	return (audit_mac_data(MAC_AUDIT_DATA_TYPE, len, sanitized));
201}
202#endif
203
204/*
205 * This is the entry point a MAC policy will call to add NULL-
206 * terminated ASCII text to the current audit record.
207 */
208int
209mac_audit_text(char *text, mac_policy_handle_t handle)
210{
211	char *sanitized;
212	const char *name;
213	int i, size, plen, len;
214
215	name = mac_get_mpc(handle)->mpc_name;
216	len = strlen(text);
217	plen = 2 + strlen(name);
218	if (plen + len >= MAC_AUDIT_DATA_LIMIT)
219		return (EINVAL);
220
221	/*
222	 * Make sure the text is only composed of only ASCII printable
223	 * characters.
224	 */
225	for (i=0; i < len; i++)
226		if (text[i] < (char) 32 || text[i] > (char) 126)
227			return (EINVAL);
228
229	size = len + plen + 1;
230 	sanitized = (char *)zalloc(mac_audit_data_zone);
231
232	strlcpy(sanitized, name, MAC_AUDIT_DATA_LIMIT);
233	strncat(sanitized, ": ", MAC_AUDIT_DATA_LIMIT - plen + 2);
234	strncat(sanitized, text, MAC_AUDIT_DATA_LIMIT - plen);
235
236	return (audit_mac_data(MAC_AUDIT_TEXT_TYPE, size, (u_char *)sanitized));
237}
238
239int
240mac_audit_check_preselect(struct ucred *cred, unsigned short syscode, void *args)
241{
242	struct mac_policy_conf *mpc;
243	int ret, error;
244	u_int i;
245
246	ret = MAC_AUDIT_DEFAULT;
247	for (i = 0; i < mac_policy_list.staticmax; i++) {
248		mpc = mac_policy_list.entries[i].mpc;
249		if (mpc == NULL)
250			continue;
251
252		if (mpc->mpc_ops->mpo_audit_check_preselect != NULL) {
253			error = mpc->mpc_ops->mpo_audit_check_preselect(cred,
254			    syscode, args);
255			ret = (ret > error ? ret : error);
256		}
257	}
258	if (mac_policy_list_conditional_busy() != 0) {
259		for (; i <= mac_policy_list.maxindex; i++) {
260			mpc = mac_policy_list.entries[i].mpc;
261			if (mpc == NULL)
262				continue;
263
264			if (mpc->mpc_ops->mpo_audit_check_preselect != NULL) {
265				error = mpc->mpc_ops->mpo_audit_check_preselect(cred,
266				    syscode, args);
267				ret = (ret > error ? ret : error);
268			}
269		}
270		mac_policy_list_unbusy();
271	}
272
273	return (ret);
274}
275
276int
277mac_audit_check_postselect(struct ucred *cred, unsigned short syscode,
278    void *args, int error, int retval, int mac_forced)
279{
280	struct mac_policy_conf *mpc;
281	int ret, mac_error;
282	u_int i;
283
284	/*
285	 * If the audit was forced by a MAC policy by mac_audit_check_preselect(),
286	 * echo that.
287	 */
288	if (mac_forced)
289		return (MAC_AUDIT_YES);
290
291	ret = MAC_AUDIT_DEFAULT;
292	for (i = 0; i < mac_policy_list.staticmax; i++) {
293		mpc = mac_policy_list.entries[i].mpc;
294		if (mpc == NULL)
295			continue;
296
297		if (mpc->mpc_ops->mpo_audit_check_postselect != NULL) {
298			mac_error = mpc->mpc_ops->mpo_audit_check_postselect(cred,
299			    syscode, args, error, retval);
300			ret = (ret > mac_error ? ret : mac_error);
301		}
302	}
303	if (mac_policy_list_conditional_busy() != 0) {
304		for (; i <= mac_policy_list.maxindex; i++) {
305			mpc = mac_policy_list.entries[i].mpc;
306			if (mpc == NULL)
307				continue;
308
309			if (mpc->mpc_ops->mpo_audit_check_postselect != NULL) {
310				mac_error = mpc->mpc_ops->mpo_audit_check_postselect(cred,
311				    syscode, args, error, retval);
312				ret = (ret > mac_error ? ret : mac_error);
313			}
314		}
315		mac_policy_list_unbusy();
316	}
317
318	return (ret);
319}
320
321#else	/* !CONFIG_AUDIT */
322
323/*
324 * Function stubs for when AUDIT isn't defined.
325 */
326
327int
328mac_system_check_audit(__unused struct ucred *cred, __unused void *record, __unused int length)
329{
330
331	return (0);
332}
333
334int
335mac_system_check_auditon(__unused struct ucred *cred, __unused int cmd)
336{
337
338	return (0);
339}
340
341int
342mac_system_check_auditctl(__unused struct ucred *cred, __unused struct vnode *vp)
343{
344
345	return (0);
346}
347
348int
349mac_proc_check_getauid(__unused struct proc *curp)
350{
351
352	return (0);
353}
354
355int
356mac_proc_check_setauid(__unused struct proc *curp, __unused uid_t auid)
357{
358
359	return (0);
360}
361
362int
363mac_proc_check_getaudit(__unused struct proc *curp)
364{
365
366	return (0);
367}
368
369int
370mac_proc_check_setaudit(__unused struct proc *curp,
371    __unused struct auditinfo_addr *ai)
372{
373
374	return (0);
375}
376
377int
378mac_audit_check_preselect(__unused struct ucred *cred, __unused unsigned short syscode,
379    __unused void *args)
380{
381
382	return (MAC_AUDIT_DEFAULT);
383}
384
385int
386mac_audit_check_postselect(__unused struct ucred *cred, __unused unsigned short syscode,
387    __unused void *args, __unused int error, __unused int retval, __unused int mac_forced)
388{
389
390	return (MAC_AUDIT_DEFAULT);
391}
392
393int
394mac_audit_text(__unused char *text, __unused mac_policy_handle_t handle)
395{
396	return (0);
397}
398#endif	/* !CONFIG_AUDIT */
399