1/*-
2 * Copyright (c) 1999-2002, 2008-2009 Robert N. M. Watson
3 * Copyright (c) 2001 Ilmar S. Habibulin
4 * Copyright (c) 2001-2003 Networks Associates Technology, Inc.
5 * Copyright (c) 2005 Samy Al Bahra
6 * Copyright (c) 2006 SPARTA, Inc.
7 * Copyright (c) 2008 Apple Inc.
8 * All rights reserved.
9 *
10 * This software was developed by Robert Watson and Ilmar Habibulin for the
11 * TrustedBSD Project.
12 *
13 * This software was developed for the FreeBSD Project in part by Network
14 * Associates Laboratories, the Security Research Division of Network
15 * Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"),
16 * as part of the DARPA CHATS research program.
17 *
18 * This software was enhanced by SPARTA ISSO under SPAWAR contract
19 * N66001-04-C-6019 ("SEFOS").
20 *
21 * This software was developed at the University of Cambridge Computer
22 * Laboratory with support from a grant from Google, Inc.
23 *
24 * Redistribution and use in source and binary forms, with or without
25 * modification, are permitted provided that the following conditions
26 * are met:
27 * 1. Redistributions of source code must retain the above copyright
28 *    notice, this list of conditions and the following disclaimer.
29 * 2. Redistributions in binary form must reproduce the above copyright
30 *    notice, this list of conditions and the following disclaimer in the
31 *    documentation and/or other materials provided with the distribution.
32 *
33 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
34 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
35 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
36 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
37 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
38 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
39 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
40 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
41 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
42 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
43 * SUCH DAMAGE.
44 */
45
46#include <sys/cdefs.h>
47__FBSDID("$FreeBSD$");
48
49#include "opt_mac.h"
50
51#include <sys/param.h>
52#include <sys/condvar.h>
53#include <sys/imgact.h>
54#include <sys/kernel.h>
55#include <sys/lock.h>
56#include <sys/malloc.h>
57#include <sys/mutex.h>
58#include <sys/mac.h>
59#include <sys/proc.h>
60#include <sys/sbuf.h>
61#include <sys/sdt.h>
62#include <sys/systm.h>
63#include <sys/vnode.h>
64#include <sys/mount.h>
65#include <sys/file.h>
66#include <sys/namei.h>
67#include <sys/sysctl.h>
68
69#include <vm/vm.h>
70#include <vm/pmap.h>
71#include <vm/vm_map.h>
72#include <vm/vm_object.h>
73
74#include <security/mac/mac_framework.h>
75#include <security/mac/mac_internal.h>
76#include <security/mac/mac_policy.h>
77
78struct label *
79mac_cred_label_alloc(void)
80{
81	struct label *label;
82
83	label = mac_labelzone_alloc(M_WAITOK);
84	MAC_POLICY_PERFORM(cred_init_label, label);
85	return (label);
86}
87
88void
89mac_cred_init(struct ucred *cred)
90{
91
92	if (mac_labeled & MPC_OBJECT_CRED)
93		cred->cr_label = mac_cred_label_alloc();
94	else
95		cred->cr_label = NULL;
96}
97
98void
99mac_cred_label_free(struct label *label)
100{
101
102	MAC_POLICY_PERFORM_NOSLEEP(cred_destroy_label, label);
103	mac_labelzone_free(label);
104}
105
106void
107mac_cred_destroy(struct ucred *cred)
108{
109
110	if (cred->cr_label != NULL) {
111		mac_cred_label_free(cred->cr_label);
112		cred->cr_label = NULL;
113	}
114}
115
116/*
117 * When a thread becomes an NFS server daemon, its credential may need to be
118 * updated to reflect this so that policies can recognize when file system
119 * operations originate from the network.
120 *
121 * At some point, it would be desirable if the credential used for each NFS
122 * RPC could be set based on the RPC context (i.e., source system, etc) to
123 * provide more fine-grained access control.
124 */
125void
126mac_cred_associate_nfsd(struct ucred *cred)
127{
128
129	MAC_POLICY_PERFORM_NOSLEEP(cred_associate_nfsd, cred);
130}
131
132/*
133 * Initialize MAC label for the first kernel process, from which other kernel
134 * processes and threads are spawned.
135 */
136void
137mac_cred_create_swapper(struct ucred *cred)
138{
139
140	MAC_POLICY_PERFORM_NOSLEEP(cred_create_swapper, cred);
141}
142
143/*
144 * Initialize MAC label for the first userland process, from which other
145 * userland processes and threads are spawned.
146 */
147void
148mac_cred_create_init(struct ucred *cred)
149{
150
151	MAC_POLICY_PERFORM_NOSLEEP(cred_create_init, cred);
152}
153
154int
155mac_cred_externalize_label(struct label *label, char *elements,
156    char *outbuf, size_t outbuflen)
157{
158	int error;
159
160	MAC_POLICY_EXTERNALIZE(cred, label, elements, outbuf, outbuflen);
161
162	return (error);
163}
164
165int
166mac_cred_internalize_label(struct label *label, char *string)
167{
168	int error;
169
170	MAC_POLICY_INTERNALIZE(cred, label, string);
171
172	return (error);
173}
174
175/*
176 * When a new process is created, its label must be initialized.  Generally,
177 * this involves inheritance from the parent process, modulo possible deltas.
178 * This function allows that processing to take place.
179 */
180void
181mac_cred_copy(struct ucred *src, struct ucred *dest)
182{
183
184	MAC_POLICY_PERFORM_NOSLEEP(cred_copy_label, src->cr_label,
185	    dest->cr_label);
186}
187
188/*
189 * When the subject's label changes, it may require revocation of privilege
190 * to mapped objects.  This can't be done on-the-fly later with a unified
191 * buffer cache.
192 */
193void
194mac_cred_relabel(struct ucred *cred, struct label *newlabel)
195{
196
197	MAC_POLICY_PERFORM_NOSLEEP(cred_relabel, cred, newlabel);
198}
199
200MAC_CHECK_PROBE_DEFINE2(cred_check_relabel, "struct ucred *",
201    "struct label *");
202
203int
204mac_cred_check_relabel(struct ucred *cred, struct label *newlabel)
205{
206	int error;
207
208	MAC_POLICY_CHECK_NOSLEEP(cred_check_relabel, cred, newlabel);
209	MAC_CHECK_PROBE2(cred_check_relabel, error, cred, newlabel);
210
211	return (error);
212}
213
214MAC_CHECK_PROBE_DEFINE2(cred_check_setuid, "struct ucred *", "uid_t");
215
216int
217mac_cred_check_setuid(struct ucred *cred, uid_t uid)
218{
219	int error;
220
221	MAC_POLICY_CHECK_NOSLEEP(cred_check_setuid, cred, uid);
222	MAC_CHECK_PROBE2(cred_check_setuid, error, cred, uid);
223
224	return (error);
225}
226
227MAC_CHECK_PROBE_DEFINE2(cred_check_seteuid, "struct ucred *", "uid_t");
228
229int
230mac_cred_check_seteuid(struct ucred *cred, uid_t euid)
231{
232	int error;
233
234	MAC_POLICY_CHECK_NOSLEEP(cred_check_seteuid, cred, euid);
235	MAC_CHECK_PROBE2(cred_check_seteuid, error, cred, euid);
236
237	return (error);
238}
239
240MAC_CHECK_PROBE_DEFINE2(cred_check_setgid, "struct ucred *", "gid_t");
241
242int
243mac_cred_check_setgid(struct ucred *cred, gid_t gid)
244{
245	int error;
246
247	MAC_POLICY_CHECK_NOSLEEP(cred_check_setgid, cred, gid);
248	MAC_CHECK_PROBE2(cred_check_setgid, error, cred, gid);
249
250	return (error);
251}
252
253MAC_CHECK_PROBE_DEFINE2(cred_check_setegid, "struct ucred *", "gid_t");
254
255int
256mac_cred_check_setegid(struct ucred *cred, gid_t egid)
257{
258	int error;
259
260	MAC_POLICY_CHECK_NOSLEEP(cred_check_setegid, cred, egid);
261	MAC_CHECK_PROBE2(cred_check_setegid, error, cred, egid);
262
263	return (error);
264}
265
266MAC_CHECK_PROBE_DEFINE3(cred_check_setgroups, "struct ucred *", "int",
267    "gid_t *");
268
269int
270mac_cred_check_setgroups(struct ucred *cred, int ngroups, gid_t *gidset)
271{
272	int error;
273
274	MAC_POLICY_CHECK_NOSLEEP(cred_check_setgroups, cred, ngroups, gidset);
275	MAC_CHECK_PROBE3(cred_check_setgroups, error, cred, ngroups, gidset);
276
277	return (error);
278}
279
280MAC_CHECK_PROBE_DEFINE3(cred_check_setreuid, "struct ucred *", "uid_t",
281    "uid_t");
282
283int
284mac_cred_check_setreuid(struct ucred *cred, uid_t ruid, uid_t euid)
285{
286	int error;
287
288	MAC_POLICY_CHECK_NOSLEEP(cred_check_setreuid, cred, ruid, euid);
289	MAC_CHECK_PROBE3(cred_check_setreuid, error, cred, ruid, euid);
290
291	return (error);
292}
293
294MAC_CHECK_PROBE_DEFINE3(cred_check_setregid, "struct ucred *", "gid_t",
295    "gid_t");
296
297int
298mac_cred_check_setregid(struct ucred *cred, gid_t rgid, gid_t egid)
299{
300	int error;
301
302	MAC_POLICY_CHECK_NOSLEEP(cred_check_setregid, cred, rgid, egid);
303	MAC_CHECK_PROBE3(cred_check_setregid, error, cred, rgid, egid);
304
305	return (error);
306}
307
308MAC_CHECK_PROBE_DEFINE4(cred_check_setresuid, "struct ucred *", "uid_t",
309    "uid_t", "uid_t");
310
311int
312mac_cred_check_setresuid(struct ucred *cred, uid_t ruid, uid_t euid,
313    uid_t suid)
314{
315	int error;
316
317	MAC_POLICY_CHECK_NOSLEEP(cred_check_setresuid, cred, ruid, euid, suid);
318	MAC_CHECK_PROBE4(cred_check_setresuid, error, cred, ruid, euid,
319	    suid);
320
321	return (error);
322}
323
324MAC_CHECK_PROBE_DEFINE4(cred_check_setresgid, "struct ucred *", "gid_t",
325    "gid_t", "gid_t");
326
327int
328mac_cred_check_setresgid(struct ucred *cred, gid_t rgid, gid_t egid,
329    gid_t sgid)
330{
331	int error;
332
333	MAC_POLICY_CHECK_NOSLEEP(cred_check_setresgid, cred, rgid, egid, sgid);
334	MAC_CHECK_PROBE4(cred_check_setresgid, error, cred, rgid, egid,
335	    sgid);
336
337	return (error);
338}
339
340MAC_CHECK_PROBE_DEFINE2(cred_check_visible, "struct ucred *",
341    "struct ucred *");
342
343int
344mac_cred_check_visible(struct ucred *cr1, struct ucred *cr2)
345{
346	int error;
347
348	MAC_POLICY_CHECK_NOSLEEP(cred_check_visible, cr1, cr2);
349	MAC_CHECK_PROBE2(cred_check_visible, error, cr1, cr2);
350
351	return (error);
352}
353