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 SECURITY_MAC_CHECK_ENFORCE
120 /* 21167099 - only check if we allow write */
121 if (!mac_proc_enforce)
122 return 0;
123#endif
124
125 if (!mac_proc_check_enforce(curp))
126 return 0;
127
128 cred = kauth_cred_proc_ref(curp);
129 MAC_CHECK(proc_check_getauid, cred);
130 kauth_cred_unref(&cred);
131
132 return (error);
133}
134
135int
136mac_proc_check_setauid(struct proc *curp, uid_t auid)
137{
138 kauth_cred_t cred;
139 int error;
140
141#if SECURITY_MAC_CHECK_ENFORCE
142 /* 21167099 - only check if we allow write */
143 if (!mac_proc_enforce)
144 return 0;
145#endif
146 if (!mac_proc_check_enforce(curp))
147 return 0;
148
149 cred = kauth_cred_proc_ref(curp);
150 MAC_CHECK(proc_check_setauid, cred, auid);
151 kauth_cred_unref(&cred);
152
153 return (error);
154}
155
156int
157mac_proc_check_getaudit(struct proc *curp)
158{
159 kauth_cred_t cred;
160 int error;
161
162#if SECURITY_MAC_CHECK_ENFORCE
163 /* 21167099 - only check if we allow write */
164 if (!mac_proc_enforce)
165 return 0;
166#endif
167 if (!mac_proc_check_enforce(curp))
168 return 0;
169
170 cred = kauth_cred_proc_ref(curp);
171 MAC_CHECK(proc_check_getaudit, cred);
172 kauth_cred_unref(&cred);
173
174 return (error);
175}
176
177int
178mac_proc_check_setaudit(struct proc *curp, struct auditinfo_addr *ai)
179{
180 kauth_cred_t cred;
181 int error;
182
183#if SECURITY_MAC_CHECK_ENFORCE
184 /* 21167099 - only check if we allow write */
185 if (!mac_proc_enforce)
186 return 0;
187#endif
188 if (!mac_proc_check_enforce(curp))
189 return 0;
190
191 cred = kauth_cred_proc_ref(curp);
192 MAC_CHECK(proc_check_setaudit, cred, ai);
193 kauth_cred_unref(&cred);
194
195 return (error);
196}
197
198#if 0
199/*
200 * This is the framework entry point for MAC policies to use to add
201 * arbitrary data to the current audit record.
202 * (Currently not supported, as no existing audit viewers would
203 * display this format)
204 *
205 */
206int
207mac_audit_data(int len, u_char *data, mac_policy_handle_t handle)
208{
209 char *sanitized;
210
211 if ((len <= 0) || (len > MAC_AUDIT_DATA_LIMIT))
212 return (EINVAL);
213
214 sanitized = (char *)zalloc(mac_audit_data_zone);
215
216 bcopy(data, sanitized, len);
217 return (audit_mac_data(MAC_AUDIT_DATA_TYPE, len, sanitized));
218}
219#endif
220
221/*
222 * This is the entry point a MAC policy will call to add NULL-
223 * terminated ASCII text to the current audit record.
224 */
225int
226mac_audit_text(char *text, mac_policy_handle_t handle)
227{
228 char *sanitized;
229 const char *name;
230 int i, size, plen, len;
231
232 name = mac_get_mpc(handle)->mpc_name;
233 len = strlen(text);
234 plen = 2 + strlen(name);
235 if (plen + len >= MAC_AUDIT_DATA_LIMIT)
236 return (EINVAL);
237
238 /*
239 * Make sure the text is only composed of only ASCII printable
240 * characters.
241 */
242 for (i=0; i < len; i++)
243 if (text[i] < (char) 32 || text[i] > (char) 126)
244 return (EINVAL);
245
246 size = len + plen + 1;
247 sanitized = (char *)zalloc(mac_audit_data_zone);
248
249 strlcpy(sanitized, name, MAC_AUDIT_DATA_LIMIT);
250 strncat(sanitized, ": ", MAC_AUDIT_DATA_LIMIT - plen + 2);
251 strncat(sanitized, text, MAC_AUDIT_DATA_LIMIT - plen);
252
253 return (audit_mac_data(MAC_AUDIT_TEXT_TYPE, size, (u_char *)sanitized));
254}
255
256int
257mac_audit_check_preselect(struct ucred *cred, unsigned short syscode, void *args)
258{
259 struct mac_policy_conf *mpc;
260 int ret, error;
261 u_int i;
262
263 ret = MAC_AUDIT_DEFAULT;
264 for (i = 0; i < mac_policy_list.staticmax; i++) {
265 mpc = mac_policy_list.entries[i].mpc;
266 if (mpc == NULL)
267 continue;
268
269 if (mpc->mpc_ops->mpo_audit_check_preselect != NULL) {
270 error = mpc->mpc_ops->mpo_audit_check_preselect(cred,
271 syscode, args);
272 ret = (ret > error ? ret : error);
273 }
274 }
275 if (mac_policy_list_conditional_busy() != 0) {
276 for (; i <= mac_policy_list.maxindex; i++) {
277 mpc = mac_policy_list.entries[i].mpc;
278 if (mpc == NULL)
279 continue;
280
281 if (mpc->mpc_ops->mpo_audit_check_preselect != NULL) {
282 error = mpc->mpc_ops->mpo_audit_check_preselect(cred,
283 syscode, args);
284 ret = (ret > error ? ret : error);
285 }
286 }
287 mac_policy_list_unbusy();
288 }
289
290 return (ret);
291}
292
293int
294mac_audit_check_postselect(struct ucred *cred, unsigned short syscode,
295 void *args, int error, int retval, int mac_forced)
296{
297 struct mac_policy_conf *mpc;
298 int ret, mac_error;
299 u_int i;
300
301 /*
302 * If the audit was forced by a MAC policy by mac_audit_check_preselect(),
303 * echo that.
304 */
305 if (mac_forced)
306 return (MAC_AUDIT_YES);
307
308 ret = MAC_AUDIT_DEFAULT;
309 for (i = 0; i < mac_policy_list.staticmax; i++) {
310 mpc = mac_policy_list.entries[i].mpc;
311 if (mpc == NULL)
312 continue;
313
314 if (mpc->mpc_ops->mpo_audit_check_postselect != NULL) {
315 mac_error = mpc->mpc_ops->mpo_audit_check_postselect(cred,
316 syscode, args, error, retval);
317 ret = (ret > mac_error ? ret : mac_error);
318 }
319 }
320 if (mac_policy_list_conditional_busy() != 0) {
321 for (; i <= mac_policy_list.maxindex; i++) {
322 mpc = mac_policy_list.entries[i].mpc;
323 if (mpc == NULL)
324 continue;
325
326 if (mpc->mpc_ops->mpo_audit_check_postselect != NULL) {
327 mac_error = mpc->mpc_ops->mpo_audit_check_postselect(cred,
328 syscode, args, error, retval);
329 ret = (ret > mac_error ? ret : mac_error);
330 }
331 }
332 mac_policy_list_unbusy();
333 }
334
335 return (ret);
336}
337
338#else /* !CONFIG_AUDIT */
339
340/*
341 * Function stubs for when AUDIT isn't defined.
342 */
343
344int
345mac_system_check_audit(__unused struct ucred *cred, __unused void *record, __unused int length)
346{
347
348 return (0);
349}
350
351int
352mac_system_check_auditon(__unused struct ucred *cred, __unused int cmd)
353{
354
355 return (0);
356}
357
358int
359mac_system_check_auditctl(__unused struct ucred *cred, __unused struct vnode *vp)
360{
361
362 return (0);
363}
364
365int
366mac_proc_check_getauid(__unused struct proc *curp)
367{
368
369 return (0);
370}
371
372int
373mac_proc_check_setauid(__unused struct proc *curp, __unused uid_t auid)
374{
375
376 return (0);
377}
378
379int
380mac_proc_check_getaudit(__unused struct proc *curp)
381{
382
383 return (0);
384}
385
386int
387mac_proc_check_setaudit(__unused struct proc *curp,
388 __unused struct auditinfo_addr *ai)
389{
390
391 return (0);
392}
393
394int
395mac_audit_check_preselect(__unused struct ucred *cred, __unused unsigned short syscode,
396 __unused void *args)
397{
398
399 return (MAC_AUDIT_DEFAULT);
400}
401
402int
403mac_audit_check_postselect(__unused struct ucred *cred, __unused unsigned short syscode,
404 __unused void *args, __unused int error, __unused int retval, __unused int mac_forced)
405{
406
407 return (MAC_AUDIT_DEFAULT);
408}
409
410int
411mac_audit_text(__unused char *text, __unused mac_policy_handle_t handle)
412{
413 return (0);
414}
415#endif /* !CONFIG_AUDIT */
416